Technical Field
[0001] The present invention relates to a refrigerator making use of a vacuum heat insulator.
Background Art
[0002] In recent years, use of vacuum heat insulators having a high adiabatic performance
(heat insulating efficiency) is examined in order to enhance the adiabatic performance
of refrigerators with a view to energy saving and space saving in refrigerators. A
vacuum heat insulator has an adiabatic performance several times to ten times as large
as that of rigid urethane foam being resin foam. In these days of an increasing demand
for energy saving, it is of urgent necessity to increase the adiabatic performance
through making use of such vacuum heat insulators to the maximum within an appropriate
range. On the other hand, in case of layering vacuum heat insulators on rigid urethane
foam to apply the same to an adiabatic box of a refrigerator, the adiabatic box is
deformed in outward appearance due to a difference in contraction coefficient between
the rigid urethane foam and the vacuum heat insulator. Japanese Utility Model Unexamined
Publication No.S61-141690 discloses a method that solves such a problem. The above
conventional refrigerator will be described below with reference to the drawings.
[0003] Fig. 40 is a cross sectional view showing a door in a front opening of a conventional
refrigerator, and Fig. 41 is a view showing, in enlarged scale, a portion A in Fig.
40. In the figures, the refrigerator has metallic shell plate 1, door frame 2 made
of a synthetic resin, inner box 3 made of a synthetic resin, foamy heat insulator
4, and vacuum heat insulator 5. Mould releasing sheet 6 interposed between vacuum
heat insulator 5 and shell plate 1 is formed to be larger than the vacuum heat insulator
5. In this manner, vacuum heat insulator 5 is disposed on an inner surface of shell
plate 1 with mould releasing sheet 6 therebetween. With such constitution, foamy heat
insulator 4 shrinks after foaming of foamy heat insulator 4 but mould releasing sheet
6 acts to generate a clearance x between shell plate 1 and mould releasing sheet 6
to prevent deformation of shell plate 1.
[0004] With such a refrigerator, however, deformation of the shell plate in outward appearance
can be prevented but a clearance is generated between the shell plate and foamy heat
insulator. Accordingly, the sense of touch is bad due to denting of the shell plate
when a user touches the same.
[0005] Japanese Patent Unexamined Publication No. H6-159922 also discloses a refrigerator
provided with vacuum heat insulators. Fig. 42 is a side, cross sectional view showing
such a conventional refrigerator. Refrigerator body 7 is composed of outer box 1A
and inner box 3. Moldable paper material 8 in the form of a bag covers a whole space
defined by outer box 1A and inner box 3, and filler 4A made of an inorganic porous
substance is filled in paper material 8. Further, vacuum heat insulator 5 is arranged
along a shape of a space enclosed by outer and inner boxes 1A, 3. Also, vacuum heat
insulator 5 has metallic foil on both surfaces thereof and is wholly planar in shape.
[0006] The present constitution makes it possible to readily accommodate vacuum heat insulator
5 between outer and inner boxes 1A, 3, and dispenses with the work of stopping up
a clearance between outer and inner boxes 1A, 3 and vacuum heat insulator 5. Also,
since the adiabatic box can be constituted only with vacuum heat insulator 5 without
rigid urethane foam, it is possible to ensure an exceedingly high adiabatic performance.
[0007] Since only vacuum heat insulator 5, which is poor in strength as compared with rigid
urethane foam, is used, however, such a refrigerator is very weak in strength while
being high in adiabatic performance. That is, deformation in outward appearance is
liable to occur. Also, since the outer and inner boxes are not planar in shape, it
is difficult to use a plate-shaped vacuum heat insulator for non-planar portions such
as convex and concave surfaces of radiating pipes or the like. Also, while the use
of vacuum heat insulator with an evaporated aluminum film on one surface thereof takes
effect in increasing the adiabatic performance, it is difficult in terms of reliability
to use vacuum heat insulators with evaporated aluminum films.
Disclosure of the Invention
[0008] A refrigerator having both resin foam and a vacuum heat insulator between an outer
box and an inner box adopts any one of the following constitutions;
(1) An outer surface of the outer box, on which the vacuum heat insulator is arranged,
are set to have a center line average roughness (Ra) of 0.1 µm or more. Alternatively,
the outer surface of the outer box is set to have a glossiness of 80 or less.
(2) A vacuum heat insulator being arranged on a door, which constitutes a front surface,
are stuck to an inner plate of the door.
(3) An intermediate member is provided between the vacuum heat insulator and the outer
box to prevent deformation of the outer surface of the outer box.
(4) A Radiating pipe is provided between the vacuum heat insulator and the outer box,
and an air gap defined by the vacuum heat insulator and the radiating pipe is made
to be communicated to outside.
(5) A Small hole is provided on the outer box, on the surface of which is provided
the vacuum heat insulator.
(6) A machine room is provided in a lower portion, and the vacuum heat insulators
are arranged on both side surfaces of an upper portion, a roof surface, a back surface,
and a front surface of a refrigerator to contact with the outer box, and on a bottom
surface and both side surfaces of the lower portion of the refrigerator, and surfaces,
which define the machine room, to contact with the inner box.
(7) The vacuumheat insulator having the radiating pipe assembled into the surface
thereof, which contacts with the outer box, is arranged inside the outer box.
Brief Description of the Drawings
[0009]
Fig. 1 is a front view showing a refrigerator according to a first exemplary embodiment
of the present invention.
Fig. 2 is a side, cross sectional view showing the refrigerator of Fig. 1.
Fig. 3 is a front, cross sectional view showing the refrigerator of Fig. 1.
Fig. 4 is an exploded view showing a door of a cold storage room of the refrigerator
prior to foaming according to the first exemplary embodiment of the invention.
Fig. 5 is a cross sectional view showing a state after the foaming in Fig. 4.
Fig. 6 is a cross sectional view showing a door of a freezing room of the refrigerator
according to the first exemplary embodiment of the invention.
Fig. 7 is an exploded view showing a door of another cold storage room of the refrigerator
prior to foaming according to the first exemplary embodiment of the invention.
Fig. 8 is a cross sectional view showing a state after the foaming in Fig. 7.
Fig. 9 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a third exemplary embodiment of the invention.
Fig. 10 is a perspective view showing an essential part of the refrigerator according
to the third exemplary embodiment of the invention.
Fig. 11 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a fourth exemplary embodiment of the invention.
Fig. 12 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a fifth exemplary embodiment of the invention.
Fig. 13 is a cross sectional view showing a vacuum heat insulator used for a refrigerator
according to a sixth exemplary embodiment of the invention.
Fig. 14 is a cross sectional view showing another vacuum heat insulator used for the
refrigerator according to the sixth exemplary embodiment of the invention.
Fig. 15 is a cross sectional view showing a still other vacuum heat insulator used
for the refrigerator according to the sixth exemplary embodiment of the invention.
Fig. 16 is a plan view showing a state before an outer box of a refrigerator according
to a seventh exemplary embodiment of the invention is bent.
Fig. 17 is a perspective view showing a state after the outer box of the refrigerator
according to the seventh exemplary embodiment of the invention is bent.
Fig. 18 is a cross sectional view showing an essential part of a vacuum heat insulator
used for the refrigerator according to the seventh exemplary embodiment of the invention.
Fig. 19 is an enlarged, cross sectional view showing a part, to which the vacuum heat
insulator used for the refrigerator according to the seventh exemplary embodiment
of the invention is applied.
Fig. 20 is an exploded, perspective view showing an essential part of one end of aluminum
tape in the refrigerator according to the seventh exemplary embodiment of the invention
after urethane is poured and foamed.
Fig. 21 is an enlarged, cross sectional view showing an essential part of a refrigerator
according to an eighth exemplary embodiment of the invention.
Fig. 22A is a cross sectional view showing a side of a refrigerator according to a
ninth exemplary embodiment of the invention.
Fig. 22B is an enlarged view showing an essential part in Fig. 22A.
Fig. 23A is a front, cross sectional view showing the refrigerator in Fig. 22A.
Figs. 23B and 23C are enlarged views showing an essential part in Fig. 23A.
Fig. 24 is a longitudinal, cross sectional view showing, in enlarged scale, an essential
part of a vacuum heat insulator applied to a refrigerator according to a tenth exemplary
embodiment of the invention.
Fig. 25 is a cross sectional view showing, in enlarged scale, a portion of the refrigerator
according to the tenth exemplary embodiment of the invention.
Fig. 26 is another cross sectional view showing, in enlarged scale, a portion of the
refrigerator according to the tenth exemplary embodiment of the invention.
Fig. 27 is an enlarged, cross sectional view showing an essential part of a refrigerator
according to an eleventh exemplary embodiment of the invention.
Fig. 28 is a view showing a transverse section of an essential part of a refrigerator
according to a twelfth exemplary embodiment of the invention.
Fig. 29 is a cross sectional view showing, in enlarged scale, a portion in the vicinity
of a radiating pipe of the refrigerator according to the twelfth exemplary embodiment
of the invention.
Fig. 30 is a perspective view showing a state before a flat sheet for an outer box
of a refrigerator according to a thirteenth exemplary embodiment of the invention
is bent.
Fig. 31 is an enlarged view showing an essential part of a refrigerator according
to a fourteenth exemplary embodiment of the invention.
Fig. 32 is an enlarged, cross sectional view showing an essential part of a refrigerator
according to a fifteenth exemplary embodiment of the invention.
Fig. 33 is an enlarged, cross sectional view showing an essential part in a position,
in which a vacuum heat insulator is positioned on an outer box of a refrigerator according
to a sixteenth exemplary embodiment of the invention.
Fig. 34 is a view showing a structure of a vacuum heat insulator applied to a refrigerator
according to a seventeenth exemplary embodiment of the invention.
Fig. 35 is a side, cross sectional view showing the refrigerator according to the
seventeenth exemplary embodiment of the invention.
Fig. 36 is a front, cross sectional view showing the refrigerator according to the
seventeenth exemplary embodiment of the invention.
Fig. 37 is a circuit diagram of a refrigerating cycle of a refrigerator according
to an eighteenth exemplary embodiment of the invention.
Fig. 38 is a view showing a structure of a vacuum heat insulator according to the
eighteenth exemplary embodiment of the invention.
Fig. 39 is a schematic view showing the vacuum heat insulator of Fig. 38.
Fig. 40 is a cross sectional view showing a door arranged on a front opening of a
conventional refrigerator.
Fig. 41 is a view showing, in enlarged scale, a portion A in Fig. 40.
Fig. 42 is a side, cross sectional view showing another conventional refrigerator.
Detailed Description of Preferred Embodiments Embodiments of the invention will be
described below with reference to the drawings. Same constituents are denoted by same
reference numerals to be explained, and detailed explanations therefor will be omitted.
(First Exemplary Embodiment)
[0010] A first exemplary embodiment of the invention will be described with reference to
Figs. 1 to 6.
[0011] Refrigerator 10 has a space defined by inner box 11 made of a synthetic resin such
as a copolymer of acrylonitrile, butadiene, styrene, (ABS) or the like, and outer
box 12 made of metal such as sheet iron, or the like, the space being filled with
rigid urethane foam (referred below to as urethane foam) 13 being a resin foam. Cold
storage room 15 and vegetable room 16 are provided above adiabatic partition 14, and
changeover room 17, ice making room 18, and freezing room 19 are provided therebelow.
Compressor 21 is arranged inside machine room 20 disposed below a rear portion of
refrigerator 10. Refrigerator 10 also has refrigerating cooler 22, refrigerating fan
23, freezing cooler 24, and freezing fan 25. Condenser 26 is arranged on a bottom
portion of refrigerator 10.
[0012] Provided on a front opening of refrigerator 10 are hinge type door (referred below
to as door) 27 for the cold storage room, drawer type door (referred below to as door)
28 for the vegetable room, drawer type door (referred below to as door) 29 for the
changeover room, drawer type door (referred below to as door) 30 for the ice making
room, and drawer type door (referred below to as door) 31 for the freezing room. Vacuum
heat insulators 32, 33, 34, 35, 36, 37, 38, 39, 40, and 41 cooperate with urethane
foam 13 to constitute a body of refrigerator 10.
[0013] Vacuumheat insulators 32, 33, 34, 36 respectively contact with inner sides of a roof
surface, a back surface, side surfaces of outer box 11, inner surfaces that constitutes
the machine-room to be stuck thereon. Vacuum heat insulator 35 contacts with a bottom
surface of inner box 12. Vacuum heat insulator 37 is arranged in adiabatic partition
14. Vacuum heat insulator 38 is arranged within door 27 in a manner to contact with
the inner box. Vacuum heat insulators 39, 40, 41, respectively, are arranged within
doors 28, 29, 31 in a manner to be disposed intermediate between external sheet iron
of the respective doors and the inner box. Although not shown, a vacuum heat insulator
is likewise arranged intermediate between the external sheet iron of door 30 and the
inner box.
[0014] Urethane foam 13 surrounding freezing room 19 and changeover room 17 in a freezing
region and vacuum heat insulators 33, 34, 35, 36 form an adiabatic box (a heat insulating
box). Preferably, an adiabatic wall thickness of the adiabatic box except the doors
is in the range of 25 to 50 mm including a portion having a thin wall at the opening.
Meanwhile, urethane foam 13 surrounding cold storage room 15 and vegetable room 16
in a cold storage region and vacuum heat insulators 32, 33, 34 also form an adiabatic
box. The thickness of an adiabatic wall of the adiabatic box is set to be in the range
of 25 to 40 mm including a portion of a thin wall at the opening except the doors.
Since a vacuum heat insulator having a thickness of 10 to 15 mm is arranged in the
adiabatic wall, a thickness of 10 mm at the minimum is ensured to fill thereinto urethane
foam 13. Therefore, flowability of urethane foam 13 at the time of foaming is not
obstructed and degradation of adiabatic performance due to roughness of the foam and
failure in filling is not caused. Thus it is possible to effectively enhance the adiabatic
performance and to maintain the adiabatic property of urethane foam 13 as a multilayered
adiabatic wall while ensuring the thickness of the vacuum heat insulator to adequately
provide its adiabatic property. In particular, it is more effective in a refrigeration
temperature range, in which temperature gradient is large between inside and outside
of the refrigerator. A thickness of an adiabatic wall surrounding freezing room 19
and changeover room 17 in the freezing region is set not to exceed 50 mm. Thereby,
it is possible to apply and make use of the vacuum heat insulators in increasing an
internal volume of freezing room 19 and changeover room 17, which are relatively small
in volume ratio, without any influence on apparent layout, thus enabling the usefulness
of the vacuum heat insulator. A thickness of the adiabatic wall of cold storage room
15 and vegetable room 16 is set not to exceed 40 mm. Thereby, energy saving by application
of the vacuum heat insulators and the effect in increasing the internal volumetric
efficiency inside and outside of the adiabatic box can be caused to balance each other
in a cold storage region, in which temperature gradient is relatively small between
inside and outside of the refrigerator.
[0015] Refrigerator 10 has component parts (not shown), irregular-shaped portions, and specific
structures such as portions, in which pipes or a drain tube are mounted. In case of
arranging a large number of vacuum heat insulators to enhance the coverage to the
utmost limits, vacuum heat insulators in specific form adapted to such portions are
needed. Alternatively, the work efficiency in sticking of the vacuum heat insulator
is exceedingly decreased. Therefore, even when it is tried to arrange the vacuum heat
insulator over substantially 80 % of the surface area of outer box 11, the insulator
is extended to locations, in which the efficiency in use is low and the usefulness
saturates. That is, the effect on an increase in adiabatic performance is exceedingly
decreased relative to charging of the vacuum heat insulator.
[0016] Accordingly, by setting the coverage of the vacuum heat insulator relative to the
surface area of outer box 11 to 80 % or less according to the present embodiment,
the effect produced by the use of a large number of vacuum heat insulators does not
saturate. That is, an endothermic load is effectively restricted in a state of high
usefulness, so that the effect of energy saving is enhanced.
[0017] Peripheral portions of the respective surfaces and partition portions between the
cooling rooms overlap each other in adiabatic wall thickness. The filling and closely
contacting quality of urethane foam 13 is decreased at opening peripheral edges to
cause a decrease in adiabatic performance. By avoiding the inefficient coverage of
the vacuum heat insulator in view of the above, the equivalent adiabatic effect to
that at the coverage of 80 % is obtained at the coverage of 70 %.
[0018] In case of the coverage of 80 %, the sticking work becomes favorable in workability
by arranging vacuum heat insulators sized to be able to substantially cover respective
surfaces composed of both side surfaces, a roof surface, a back surface, a bottom
surface, and a front surface of the adiabatic box.
[0019] Therefore, it is possible to avoid the use of vacuum heat insulators of nonstandard
configuration and the work of arranging the vacuum heat insulators on those portions,
which are low in workability, so that cost performance becomes favorable. That is,
balance between an increase in initial cost of refrigerator 10 due to application
of the adiabatic box and a decrease in running cost due to energy saving is not lost.
Therefore, it is possible to increase the value as life cycle cost.
[0020] When arrangement from locations, in which thermal gradient is large inside and outside
of the adiabatic box presents the coverage amounting 50 % or more of the surface area
of outer box 12, the endothermic load of the adiabatic box is effectively restricted,
so that the effect of energy saving is enhanced.
[0021] From the viewpoint of cost-effectiveness, the effect of energy saving to investment
is large in the range of 50 to 70 % in rate of contribution.
[0022] For such reason, it is preferable that the vacuum heat insulators be arranged on
respective surfaces composed of both the side surfaces, the roof surface, the back
surface, the bottom surface, and the front surface of refrigerator 10 to have the
coverage of vacuum heat insulators amounting 50 % or more but 80 % or less and more
preferably 50 % or more but 70 % or less of the surface area of the outer box.
[0023] Temperature gradient of, for example, respective doors 27, 28, 29, 30, 31 between
inside and outside of the refrigerator is relatively smaller than that of those other
portions of the adiabatic box, with which exhaust heat of machine room 20 is associated.
Strength is necessary for articles, which are received in the refrigerator and supported
by respective doors, and for mechanical peel of the vacuum heat insulator, which is
caused by opening and closing of the doors. In view of this, it is conceivable to
restrain arrangement of the vacuum heat insulators on respective doors and to effectively
obtain the effect of application of the vacuum heat insulators to other body portions
of the adiabatic box. At this time, the coverage of the vacuum heat insulator amounts
to about 53 % in a refrigerator, which has a height of 1800 mm, a width of 675 mm,
and a depth of 650 mm, to provide an energy-saving refrigerator, to which a vacuum
heat insulator having a stuck area of 50 to 80 % is reasonably applied.
[0024] Outer surfaces of outer box 11, on which vacuum heat insulators 32, 33, 34 are arranged,
are set to have a center line average roughness (Ra) of 0.1 µm or more to be rougher
than conventional ones having a center line average roughness of less than 0.1 µm.
[0025] A method of manufacturing cold storage room door 27 will be described with reference
to Figs. 4 and 5. Door inner plate 42 has projections 43 and vacuum heat insulator
38 is stuck thereto in a manner to contact with a surface of forefront portion 44.
After urethane foam 13 is poured inside door outer plate 27A, it covers door inner
plate 42 to be foamed to form door 27.
[0026] Fig. 6 is a cross sectional view showing drawer type door 31 for the freezing room.
Door inner plate 45 has fixing portions 47 to fix thereto rails 46, which support
a casing (not shown) for storage of frozen food. Urethane foam 13 together with reinforcement
plate 48 fixes door inner plate 45 to rails 46 at fixing portions 47. Spacers 49 are
fixed to a part of reinforcement plate 48 by an adhesive or the like in a manner to
arrange vacuum heat insulator 41 in a space between door inner plate 45 and door outer
plate 50. Spacers 49 are made of softer members, such as foamed styrene, and polyethylene
foam, than vacuum heat insulator 41. Spacers 49 are substantially shaped in a rectangular
solid and arranged to have a flow direction of urethane foam 13 at the time of foaming
and a longitudinal direction of spacers 49 agreeing with each other.
[0027] With the above construction, a cooling apparatus is composed of compressor 21, refrigerating
cooler 22, refrigerating fan 23, freezing cooler 24, freezing fan 25, and condenser
26. Such a cooling apparatus cools cold storage room 15 and vegetable room 16 substantially
to 0 to 10 °C and changeover room 17, ice making room 18, and freezing room 19 substantially
to a temperature of -15 to -25 °C.
[0028] When the vacuum heat insulators are arranged from locations, in which thermal gradient
is large inside and outside of the box body, to have the coverage amounting 50 % or
more of the surface area of the outer box, an endothermic load of the refrigerator
can be effectively restricted. Thereby, it is possible to enhance the effect of energy
saving. By making the coverage 80 % or less, the use of vacuum heat insulators of
nonstandard configuration and the work of arranging the vacuum heat insulators on
those portions, which are low in workability are avoided. That is, it is possible
to avoid a sudden increase in cost ratio relative to a decrease in endothermic load
of the vacuum heat insulators and to effectively restrict the endothermic load in
a state of high usefulness of the vacuum heat insulators to enhance the effect of
energy saving.
[0029] Since vacuum heat insulators 32, 33, and 34 are stuck to outer box 11 in contact
therewith, deformation possiblyoccurs on outer surfaces of outer box 11 due to the
cause of dispersion in flatness, such as irregularities, warpage, or the like, of
surfaces of vacuum heat insulators 32, 33, and 34. Since the outer surfaces of outer
box 11 are set to have a center line average roughness (Ra) of 0.1 µm or more to be
rougher than conventional ones, the outer surfaces of the outer box are decreased
in light reflectance with the same coating material. Thereby, deformation of the outer
surfaces of the outer box caused by sticking of the vacuum heat insulators is visually
decreased. Accordingly, it is possible to cope with deformation of refrigerator 10
in outward appearance without the use of any complex construction or any specific
parts and materials. Desirably, the center line average roughness (Ra) of the outer
surfaces of outer box 11 is 1 µm or less, which does not mar the quality in outward
appearance.
[0030] After sticking vacuum heat insulator 38 to forefront portion 44 of door inner plate
42 in a manner to contact with the same and pouring urethane foam 13, the urethane
foam is caused to cover door inner plate 42 to be foamed to form door 27. Therefore,
vacuumheat insulator 38 does not contact directly with the outer surface of door 27
and the outer surface of door 27 for the cold storage room is not deformed due to
shrinkage after the foaming of urethane foam 13.
[0031] Since vacuum heat insulator 38 is stuck to forefront portion 44 of door inner plate
42 in a manner to contact with the same, vacuum heat insulator 38 can be arranged
to the maximum to enhance the adiabatic performance. Further, urethane foam 13 is
filled into projections 43 formed inside door inner plate 42 from a space between
vacuum heat insulator 38 and door inner plate 42, so that projections 43 are increased
in strength.
[0032] Vacuum heat insulator 41 provided on door 31 is arranged in a space between door
outer plate 50 and door inner plate 45 partially with spacers 49 therebetween. Therefore,
the outer surface of door outer plate 50 is not deformed due to shrinkage after foaming
of urethane foam 13. Urethane foam 13 is surely formed in the vicinity of fixing portions
47 of rails 46 and reinforcement plate 48 disposed on door inner plate 45, so that
rail fixing portions 47 are increased in strength.
[0033] Since spacers 49 are made of a softer material than vacuum heat insulator 41, the
covering of vacuum heat insulator 41 is not damaged and so can be heightened in reliability.
[0034] Spacers 49 are substantially shaped in a rectangular solid and arranged to have a
flow direction of urethane foam 13 at the time of foaming and a longitudinal direction
of spacers 49 agreeing with each other. Therefore, the construction decreases hamper
against the flow of urethane foam 13 by spacers 49at the time of foaming, so that
urethane is improved in filling quality and rail fixing portions 47 are surely increased
in strength.
[0035] While door 31 for the freezing room is described as a drawer door of the refrigerator
according to the present embodiment, it is effective that door 28 for the vegetable
room and door 29 for the changeover room, which constitute drawer doors, be constructed
in the same manner.
[0036] In the above description, single vacuum heat insulator 38 is used for door 27 for
the cold storage room. As shown in Figs. 7 and 8, however, vacuum heat insulators
38A, 38B may be arranged in the vicinity of projections 43 with gaps therebetween
to contact with door inner plate 42 of a single door. In this case, urethane foam
13 is more surely filled into projections 43, so that projections 43 on door 27B for
the cold storage room are increased in strength.
(Second Exemplary Embodiment)
[0037] A refrigerator according to a second exemplary embodiment of the invention is the
same in fundamental construction as that according to the first exemplary embodiment.
According to the first exemplary embodiment, the center line average roughness of
the outer surfaces of outer box 11 is prescribed. According to the present embodiment,
those outer surfaces of outer box 12, on which vacuum heat insulators 32, 33, and
34 are provided, are decreased in glossiness below the order of 90, which is conventional,
and set to 80 or less.
[0038] Here, glossiness is prescribed in JIS standard (JIS Z8741) such that glossiness 100
corresponds to reflectance 10 % in case of an incidence angle of 60 degrees on a glass
surface having a refractive index of 1.567, or glossiness 100 corresponds to reflectance
5 % in case of an incidence angle of 20 degrees.
[0039] Likewise the first exemplary embodiment, vacuum heat insulators 32, 33, and 34 are
stuck to outer box 12 in contact therewith. Therefore, deformation possibly occurs
on the outer surfaces of outer box 12 due to the cause of dispersion in flatness ,
such as irregularities, warpage, or the like, of surfaces of vacuum heat insulators
32, 33, and 34. Hereupon, since the outer surfaces of outer box 12 have the glossiness
of 80 or less, the outer surfaces of the outer box are decreased in light reflectance
with the same surface roughness. Accordingly, deformation of the outer surfaces of
the outer box caused by sticking of the vacuum heat insulators is visually decreased.
Therefore, it is possible to cope with deformation of refrigerator 10, to which the
vacuum heat insulators are applied, in outward appearance without the use of any complex
construction or any specific parts and materials. Desirably, the glossiness of the
outer surfaces of outer box 12 is preferably around 50, which does not mar the quality
in outward appearance.
(Third Exemplary Embodiment)
[0040] Fig. 9 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a third exemplary embodiment of the invention, and Fig. 10 is a perspective
view showing the essential part. The fundamental construction except the essential
part is the same as that according to the first exemplary embodiment.
[0041] In the figures, arranged between outer box 51 and inner box 52 are soft member 53,
vacuum heat insulator 54, and rigid urethane foam 55 as intermediate members, which
prevent deformation of outer surfaces of outer box 51 from a side of the outer box.
It is preferred that soft member 53 be larger than vacuum heat insulator 54 and made
of a softer material than vacuum heat insulator 54. Preferably, the soft member is
resin foam structured of, for example, independent foam.
[0042] Preferably, soft member 53 has a thickness t1 of at least the flatness of vacuum
heat insulator 54 and at most the thickness of the vacuum heat insulator. Concretely,
the thickness is set to be at least 3 mm and at most 15 mm.
[0043] With the above structure, soft member 53 provided between vacuum heat insulator 54
and outer box 51 prevents deformation of the outer surfaces of the outer box. Thereby,
the cause of dispersion in flatness, such as irregularities, warpage, or the like,
of surfaces of vacuum heat insulator 54 is absorbed and deformation of the outer surfaces
of the outer box is prevented.
[0044] When soft member 53 is larger than vacuum heat insulator 54, dispersion in mounting
at the time of sticking vacuum heat insulator 54 to outer box 51 is absorbed and the
work efficiency is enhanced.
[0045] When soft member 53 is softer than vacuum heat insulator 54, the covering of vacuum
heat insulator 54 is not damaged at the time of manufacture and so vacuum heat insulator
54 is heightened in reliability.
[0046] When soft member 53 as an intermediate member is a member made of resin foam, pressure
of foaming generated at the time of foaming of rigid urethane foam (referred below
to as urethane foam) 13 is absorbed by compression of the resin foam. Shrinkage of
the urethane foam after the foaming is absorbed by expansion of the resin foam, so
that deformation of the outer surfaces of the outer box is surely prevented.
[0047] When soft member 53 is a member structured of independent foam, entry of gases such
as foamed gas, air, or the like into soft member 53 is prevented, so that deformation
of the outer surfaces of the outer box due to temperature changes is prevented.
[0048] The thickness t1 of soft member 53 is at least the flatness of vacuum heat insulator
54 and at most the thickness of the vacuum heat insulator, and is concretely set to
be at least 3 mm and at most 15 mm. Thereby, dispersion in flatness of the vacuum
heat insulator is surely absorbed by the soft member and soft member 53 is not larger
in thickness than needed, whereby degradation in adiabatic performance is not caused.
[0049] Vacuum heat insulator 54 may be stuck to soft member 53 after the soft member is
stuck to outer box 51, or soft member 53 may be stuck to outer box 51 after the soft
member is beforehand stuck to outer box 51.
(Fourth Exemplary Embodiment)
[0050] Fig. 11 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a fourth exemplary embodiment of the present invention. The fundamental
construction except the essential part is the same as that according to the first
exemplary embodiment.
[0051] Hard member 56 as an intermediate member provided between vacuum heat insulator 54
and outer box 51 is a harder member than vacuum heat insulator 54. The hard member
is made of, for example, ABS sheet and preferably has a thickness of at least the
flatness of vacuum heat insulator 54, concretely at least 3 mm.
[0052] With the above structure, the cause for deformation of the outer box, such as irregularities,
warpage, or the like, of surfaces of vacuum heat insulator 54 is prevented, and deformation
of the outer surfaces of the outer box is prevented. Since hard member 56 can be made
relatively small in thickness, it is possible to restrict an influence on the adiabatic
performance.
(Fifth Exemplary Embodiment)
[0053] Fig. 12 is a cross sectional view showing an essential part of a side wall of a refrigerator
according to a fifth exemplary embodiment of the present invention. The fundamental
construction except the essential part is the same as that according to the first
exemplary embodiment.
[0054] In the figure, soft member 53 and hard member 56 are arranged between vacuum heat
insulator 54 and outer box 51. Hard member 56, soft member 53, and vacuum heat insulator
54 from a side of outer box 51 are arranged in this order.
[0055] With the above structure, soft member 53 absorbs the cause for deformation of the
outer box, such as irregularities , warpage, or the like, of surfaces of vacuum heat
insulator 54, and hard member 56 prevents transmission of the cause for deformation
of the outer box, so that deformation of the outer surfaces of the outer box is surely
prevented.
[0056] Since hard member 56, soft member 53, and vacuum heat insulator 54 from a side of
outer box 51 are arranged as intermediate members in this order, damage to the covering
of the vacuum heat insulator is prevented by soft member 53.
(Sixth Exemplary Embodiment)
[0057] Figs. 13 to 15 are cross sectional views showing various vacuum heat insulators used
in a refrigerator according to a sixth exemplary embodiment of the invention. The
fundamental construction except the vacuum heat insulators is the same as that according
to the first exemplary embodiment.
[0058] Core material 57 charged in the vacuum heat insulator is sealed at its periphery
by first covering 58 and kept in a vacuum state after its interior is exhausted. An
outer periphery of first covering 58 is covered by second covering 59 to provide for
a dual structure. In Fig. 13, gas is charged in space 60 between first covering 58
and second covering 59. As the gas, air or inert gas is used.
[0059] In this manner, the outer periphery of first covering 58, on which deformation of
the outer box, such as irregularities, warpage, or the like, of surfaces of core material
57 charged in the vacuum insulator occurs, is covered by second covering 59 to provide
for the dual structure. Thereby, second covering 59 absorbs the cause for deformation
of the outer box to prevent deformation of the outer surfaces of the outer box. And
gas is charged between coverings 58, 59 of the dual structure. Thereby, the cause
for deformation of the outer box, such as irregularities, warpage, or the like, of
surfaces of the vacuum heat insulator is absorbed by space 60 for the gas charged
between coverings 58, 59 of the dual structure, so that deformation of the outer surfaces
of the outer box is prevented.
[0060] As shown in Fig. 14, covering 59B of the dual structure may have a larger thickness
t3 than a thickness t2 of covering 59A and covering 59B may be stuck to outer box
12. In this case, since thickness t3 of covering 59B is large, the cause for deformation
of the outer box, such as irregularities, warpage, or the like, of surfaces of the
vacuum heat insulator is absorbed by thickness t3, so that deformation of the outer
surfaces of the outer box is prevented.
[0061] As shown in Fig. 15, covering 59 may cover an outer periphery of first covering 58
to provide for a dual structure, and soft member 61 may be charged between the coverings
of the dual structure. In this case, soft member 61 absorbs the cause for deformation
of the outer box, such as irregularities, warpage, or the like, of surfaces of the
vacuum heat insulator to prevent deformation of the outer surfaces of the outer box.
Soft member 61 acts to protect the vacuum heat insulator to heighten the vacuum heat
insulator in reliability.
(Seventh Exemplary Embodiment)
[0062] Fig. 16 is a plan view showing a state before an outer box of a refrigerator according
to a seventh exemplary embodiment of the invention is bent, and Fig. 17 is a perspective
view showing a state after the outer box of the refrigerator is bent. Fig. 18 is a
cross sectional view showing an essential part of a vacuum heat insulator used for
the refrigerator, Fig. 19 is an enlarged, cross sectional view showing a part, to
which the vacuum heat insulator used for the refrigerator is applied, and Fig. 20
is an exploded, perspective view showing an essential part of one end of aluminum
tape in the refrigerator after urethane is poured and foamed. The fundamental construction
except the above parts is the same as that according to the first exemplary embodiment.
[0063] Outer box 62 made of steel sheet is in the form of a flat sheet before bending. Radiating
pipe 63 constituting a refrigerating cycle is fixed to outer box 62 by aluminum tape
64, which serves as a fixing member, and to an upper surface of which is fixed vacuum
heat insulators 65, 66, 67 with the use of an adhesive such as hot melt, etc. Outer
box 62 is bent at bends 69 to assemble thereto back surface plate 70, bottom plate
71, and an inner box (not shown). Thereafter, rigid urethane foam is filled into a
space, which is defined by outer box 62 and the inner box, to be foamed. Accordingly,
the urethane foam is not filled into machine room constituting portion 68, which accommodates
therein a compressor of the refrigerating cycle, the portion being communicated to
outside. One end 64A of aluminum tape 64 for fixing radiating pipe 63 is extended
to machine room constituting portion 68. Other end 64B of aluminum tape 64 is positioned
inside vacuum heat insulator 65.
[0064] After completion, vacuum heat insulator 65 is provided with groove 74 by means of
pressing portion 73 of press machine 72. Vacuum heat insulator 65 is arranged on and
fixed to outer box 62 such that radiating pipe 63 enters groove 74.
[0065] When radiating pipe 63 is arranged between outer box 62 and vacuum heat insulator
65, first air gap 76 is defined between outer box 62 and aluminum tape 64. Second
air gap 77 is defined between aluminum tape 64 and groove 74 on vacuum heat insulator
65.
[0066] With the above structure, first air gap 76 and second air gap 77 are communicated
to outside because one end 64A of aluminum tape 64 is extended to machine room constituting
portion 68. Accordingly, gas such as foaming gas does not stay in air gaps 76, 77.
Therefore, air gaps 76, 77 are neither expanded nor contracted by changes in ambient
temperature, so that an outer surface of outer box 62 in an area, in which radiating
pipe 63 is arranged, is prevented from being deformed.
[0067] One end 64A of aluminum tape 64 is extended to machine room constituting portion
68 and other end 64B is positioned inside an end of vacuum heat insulator 65. When
rigid urethane foam 75 is foamed, some urethane foam 75 enters from a clearance between
vacuum heat insulator 65 and radiating pipe 63. With such construction, however, the
urethane foam does not reach other end 64B of aluminum tape 64 as shown in Fig. 20.
Accordingly, since air gaps 76, 77 in the vicinity of other end 64B of aluminum tape
64 are communicated to each other, gas in air gaps 76, 77 is smoothly discharged outside
the refrigerator. Thereby, the air gaps are neither expanded or nor contracted by
changes in ambient temperature, so that an outer surface of outer box 62 in an area,
in which radiating pipe 63 is arranged, is surely prevented from being deformed.
[0068] Groove 74 formed in vacuum heat insulator 65 in opposition to radiating pipe 63 is
formed by pressing portion 73 of press machine 72 after vacuum heat insulator 65 is
completed. Accordingly, there is no need of beforehand providing a groove on a core
material of vacuum heat insulator 65, so that it is possible to make the manufacturing
process of the vacuum heat insulator simple.
[0069] While the aluminum tape is explained as a fixing member, the material is not specifically
limited thereto provided that it is a tape material having stickiness. Further, the
material more preferably has a thermal conductivity.
(Eighth Exemplary Embodiment)
[0070] Fig. 21 is an enlarged, cross sectional view showing an essential part of a refrigerator
according to an eighth exemplary embodiment of the invention. The fundamental construction
except the essential part is the same as that according to the first exemplary embodiment.
[0071] Small holes 78 beforehand formed on outer surfaces of outer box 62 by means of press
machine or the like are linearly provided on outer box 62 to correspond to an area,
in which vacuum heat insulator 65 is provided.
[0072] With the above structure, gas in an air gap between vacuum heat insulator 65 and
outer box 62 constitutes the cause for deformation of the outer box, such as irregularities,
warpage, or the like, of surfaces of vacuum heat insulator 65. The gas passes through
small holes 78 to be smoothly discharged outside the refrigerator. Thereby, the air
gap is neither expanded nor contracted by changes in ambient temperature, so that
an outer surface of outer box 62 in an area, in which vacuum heat insulator 65 is
arranged, is prevented from being deformed.
[0073] A pattern, in which small holes 78 are arranged, is not limited to be linear but
may be curved or polygonal.
(Ninth Exemplary Embodiment)
[0074] Fig. 22A is a cross sectional view showing a left side among left and right sides,
into which a refrigerator according to a ninth exemplary embodiment of the invention
is divided, as viewed from the right side, and Fig. 23A is a cross sectional view
showing a rear portion among front and rear portions, into which the refrigerator
is cut into, as viewed from the front.
[0075] The fundamental construction of the refrigerator according to this embodiment is
different from that according to the first exemplary embodiment in a way of arranging
vacuum heat insulators. That is, vacuum heat insulators 32, 33A, 33B, and 34 contact
with a roof surface, a back surface, inner sides of upper side surfaces of outer box
12, respectively, to be stuck thereto. Vacuum heat insulators 35, 34A, and 36 contact
with a bottom surface, and lower side surfaces of inner box 11, and constituent surfaces
of machine room 20, respectively, to be stuck thereto. Vacuum heat insulators 38,
39, 40, and 41, respectively, are arranged inside cold storage room door 27, vegetable
room door 28, and freezing room doors 29, 31, which are arranged on a front opening
of refrigerator 10, to contact with outer sheet iron of the respective doors.
[0076] According to this embodiment, the respective vacuum heat insulators are arranged
from locations, in which thermal gradient is large inside and outside of an adiabatic
box, and an endothermic load is effectively restricted in a state of high usefulness
of the vacuum heat insulators, so that the effect of energy saving is enhanced.
[0077] Further, the respective vacuum heat insulators are arranged on the both upper side
surface, the roof surface, the back surface, and the front surface of refrigerator
to contact with outer box 12, and on the bottom surface and the constituent surfaces
of machine room 20 to contact with inner box 11. Accordingly, vacuum heat insulators
35, 34A, 36, and 37 arranged on the both lower side surfaces, the bottom surface,
and machine room 20, where outer box 12 rises in surface temperature, are not exposed
to high temperatures. Therefore, deterioration in vacuum adiabatic performance with
the passage of time can be restricted to the minimum, so that reliability of vacuum
heat insulators 35, 34A, 36, and 37 over a long term is heightened.
[0078] Since vacuum heat insulators 34A on the both lower side surfaces are arranged to
contact with inner box 11, complex fitting portions and complex piping of outer box
12 are avoided and breakage of vacuum heat insulators 34A is prevented. That is, reliability
is heightened by arranging vacuum heat insulators 34A to contact with inner box 11
on the both lower side surfaces where outer box 12 are complex in shape.
[0079] Since vacuum heat insulator 32 on the roof surface is arranged to contact with outer
box 12, a mount member for inside illumination or electric wire (not shown) can be
mounted on the roof surface of inner box 11. Accordingly, it is possible to provide
the illumination on the roof surface of refrigerator 15, thus improving convenience
in use.
[0080] By arranging vacuum heat insulators 33A and 33B on the back surface of the adiabatic
box, the vacuum heat insulators are not in the way of piping for cooling devices and
drain tubes (not shown) for draining of defrosting water from coolers 22 and 24. A
back panel and vacuum heat insulators 33A, 33B can be assembled to be unitary, which
is preferable in manufacturing process.
[0081] Further, since the respective vacuum heat insulators are arranged to contact with
either outer box 12 or inner box 11, which constitute the adiabatic box of the refrigerator,
it is possible to ensure adequate spatial distances, over which rigid urethane foam
13 being resin foam is formed. Accordingly, degradation in adiabatic performance due
to roughness and insufficient foaming of urethane foam 13 is not brought about but
the box is maintained in strength and becomes impressive.
[0082] Adiabatic wall thicknesses of the adiabatic box, which forms freezing rooms 18A,
19 in a freezing region, and the adiabatic box, which forms cold storage room 15 and
vegetable room 16 in a cold storage region, are the same as those in the first exemplary
embodiment, and so an explanation therefor is omitted. The same is the case with the
coverage of outer surfaces of refrigerator 10.
[0083] Vacuum heat insulators 33A, 33B are beforehand arranged on the back panel, and then
joined to side surfaces and the roof surface, which are formed by bending a flat sheet
in a C-shaped manner, to form outer box 12. At this time, vacuum heat insulators 33A,
33B are preferably arranged to be positioned in the vicinity of joints, which is made
when outer box 12 is constituted. That is, vacuum heat insulators 33A, 33B are fabricated
to be of substantially the same size in width of back panel as that of the back panel.
Thereby, the adiabatic performance is heightened.
[0084] Preferably, the respective vacuum heat insulators are beforehand arranged on outer
box 12 or inner box 11. Manufacture is facilitated by assembling the box in such a
manner.
[0085] Vacuum heat insulators 35, 34A, 36, and 37 arranged in contact with inner box 11
are preferably made smaller in projected area than inner box 11. In other words, vacuum
heat insulators 35, 34A, 36, and 37 arranged in contact with inner box 11 do not protrude
beyond respective surfaces of inner box 11, with which vacuum heat insulators 35,
34A, 36, 37 are arranged in contact.
[0086] With such a constitution, urethane foam 13 is caused to flow between outer box 12
and inner box 11 after vacuum heat insulators 35, 34A, 36, 37 are arranged in predetermined
locations. In this case, forces acting in directions, in which vacuum heat insulators
35, 34A, 36, 37 arranged on inner box 11 are peeled off from inner box 11, are not
exerted on the vacuum heat insulators. Therefore, it is possible to prevent peeling-off
of vacuum heat insulators 35, 34A, 36, 37 caused by inflowing of urethane foam 13.
Further, sticking of vacuum heat insulators 35, 34A, 36, and 37 can be readily stabilized,
and flowability of urethane foam 13 is not hindered.
[0087] Those surfaces of inner box 11, with which vacuum heat insulators 35, 34A, 36 are
arranged in contact, are preferably provided with projection 11A, which surrounds
an outer periphery of each vacuum heat insulator as shown in Fig. 23B, or recess 11B,
which receives each vacuum heat insulator as shown in Fig. 23C. Both projection 11A
and recess 11B have a step in contact with an outer periphery of the vacuum heat insulator.
The step reduces an exposed area of an end surface of each vacuum heat insulator.
[0088] By providing the step in this manner, positioning is made easy when vacuum heat insulators
35, 34A, 36 are stuck, so that breakage of respective vacuum heat insulators is prevented.
Further, peeling-off of respective vacuum heat insulators caused by inflowing of urethane
foam 13 is prevented. Differences in level between inner box 11 and vacuum heat insulators
35, 34A, 36 are decreased by the provision of projections 11A, and so flowability
of urethane foam 13 is not hindered. Working of a metal mold for inner box 11 is facilitated
by the provision of recesses 11B. Further, the steps themselves serve for reinforcement
of inner box 11 to facilitate sticking of vacuum heat insulators 35, 34A, 36.
[0089] In case of arranging vacuum heat insulator 36 below cooler 24, heat insulator 36A
is preferably arranged below cooler 24, or on an inner surface of inner box 11 to
ensure a planar configuration as shown in Fig. 22B. Heat insulator 36A is formed on
an upper surface thereof with a predetermined inclined configuration for treatment
of defrosting water, and on a lower surface thereof with a planar configuration to
be brought into close contact with inner box 11. A hole is provided on a lowermost
portion of the upper surface of heat insulator 36A and a path is provided to afford
discharging defrosting water outside from the hole.
[0090] A surface of inner box 11 positioned below cooler 24 is made planar by heat insulator
36A and provided with no inclined portion, so that it is possible to efficiently stick
vacuum heat insulator 36 to the surface. It is possible to prevent peeling-off of
vacuum heat insulator 36 caused by inflowing of urethane foam 13. Since that portion,
to which vacuum heat insulator 36 is stuck, is not inclined in shape but planar, side
length is shortened to enable reducing vacuum heat insulator 36 in size. Since side
length is shortened, it is possible to decrease an endothermic load into the refrigerator.
[0091] In the above explanation, the inner surface of inner box 11 below cooler 24, on which
heat insulator 36A is arranged, is planar. However, a portion below cooler 24 in inner
box 11 may be made an inclined surface and heat insulator 36A may be arranged on an
outer surface of inner box 11 corresponding to the portion. In this case, vacuum heat
insulator 36 is beforehand arranged on heat insulator 36A and the box can be assembled,
so that manufacture is facilitated.
[0092] Preferably, air vent holes 11C are disposed on a back surface of inner box 11 for
releasing air from urethane foam 13 as shown in Fig. 23A. With such a constitution,
any air vent hole is unnecessary for the back surface of outer box 12 and vacuum heat
insulator 33A can be arranged thereon. Further, air vent holes disappear from outer
box 12, thus enabling ensuring a beautiful view in outward appearance. The back surface
can also be used for back surfaces of outer boxes of otherwise constructed refrigerators,
so that it is possible to reduce the number of parts and manhour.
[0093] Preferably, a boundary between vacuum heat insulators 34 and 34A is structured such
that vacuum heat insulators 34 and 34A overlap each other as shown in Fig. 23A. According
to this embodiment, lower ends of vacuum heat insulators 34 arranged in contact with
outer box 12 on both upper side surfaces of refrigerator 10 are positioned to be lower
than upper ends of vacuum heat insulators 34A arranged in contact with inner box 11
on both lower side surfaces of the refrigerator. When vacuum heat insulators 34, 34A
are arranged on both side surfaces of refrigerator 10, they may be shifted in a vertical
direction. Vacuum heat insulators 34, 34A may be low in dimensional accuracy. Even
in such cases, the vacuum heat insulators are present on at least one of outer box
12 and inner box 11 over the entire both side surfaces of refrigerator 10. Therefore,
vacuum heat insulators 34, 34A are not damaged in adiabatic effect. Further, urethane
foam 13 can be made to flow stably without hamper.
[0094] Inner box 11 is preferably planar in a widthwise direction so as to make sticking
of vacuum heat insulators 35, 36 easy and effective. According to this embodiment,
vacuum heat insulators 35, 36 are arranged in contact with outer sides of bottom surfaces
of inner box 11, on which flat surfaces are formed in a widthwise direction of refrigerator
10. Such a constitution makes it possible to enlarge an area, in which vacuum heat
insulators 35, 36 are stuck on bottom surfaces of inner box 11, and to decrease the
bottom surfaces in area, thus enabling enhancing the energy saving effect. Further,
the sticking quality of vacuum heat insulators 35, 36 is improved.
[0095] In arranging vacuum heat insulators 32, 33A, 33B, 35, 34, 34A, 36, 37, 38, 39, 40,
and 41, it is preferable to remove foreign matters from those surfaces, to which they
are stuck, before sticking. According to this embodiment, foreign matters on those
surfaces in contact with the respective vacuum heat insulators before sticking of
the vacuum heat insulators are removed. Thereby, damage to the respective vacuum heat
insulators due to foreign matters can be eliminated, so that reliability in the sticking
process is enhanced.
(Tenth Exemplary Embodiment)
[0096] Fig. 24 is a cross sectional view showing an essential part of a vacuum heat insulator
applied to a refrigerator according to this exemplary embodiment, and Figs. 25 and
26 are partial, cross sectional views showing, in enlarged scale, the refrigerator
according to this embodiment. The fundamental construction of the whole refrigerator
is the same as that according to the first exemplary embodiment or the ninth exemplary
embodiment.
[0097] Vacuum heat insulator 91 has core material 92 therein. Core material 92 is made of
an inorganic fiber aggregate such as glass wool etc. Vacuum heat insulator 91 is formed
by inserting core material 92 into a covering member, which is formed by sticking
deposited layer film 93 and metallic foil layer film 97 together after the core material
is heated and dried, and vacuumizing an interior of the covering member to seal an
opening thereof.
[0098] Deposited layer f ilm 93 has a composite plastic film formed by interposing aluminum
deposited film 95 between nylon film 94 and high-density polyethylene film 96. Metallic
foil layer film 97 has a composite plastic film formed by interposing aluminum foil
99 between nylon film 98 and high-density polyethylene film 100.
[0099] Sealing surfaces of deposited layer film 93 and metallic foil layer film 97 serves
a flat surface on a side of deposited layer film 93 and a three-dimensional surface
on a side of metallic foil layer film 97. Deposited layer film 93 is arranged in contact
with outer box 12 or inner box 11. That is, that flat surface of vacuum heat insulator
91, which needs a high adiabatic quality, is composed of deposited layer film 93 having
aluminum deposited film 95. The other surface, which needs a high gas-barrier quality,
is composed of metallic foil layer film 97 having metallic foil 99. The sealing surfaces
of both films 93, 97 are caused to be positioned on the same plane as that of the
flat surface on the side of deposited layer film 93. With such a constitution, it
becomes easy to treat fins of the sealing surfaces and it is possible to make use
of vacuum heat insulator 91 having a high reliability and an excellent adiabatic performance.
[0100] According to the embodiment, the flat surface of vacuum heat insulator 91 on the
side of deposited layer film 93 is arranged in contact with an inside of outer box
12 or an outside of inner box 11 as shown in Figs. 25 and 26. Thereby, vacuum heat
insulator 91 having a high reliability and an excellent adiabatic performance can
be effectively positioned and treatment of fins on the sealing surfaces is made unnecessary.
[0101] A vacuum heat insulator having metallic foil films on both surfaces thereof is used
for those portions of both inner box 11 and outer box 12, which are too complex in
shape to permit a vacuum heat insulator to be stuck thereto, or for which it is important
to ensure reliability for the vacuumheat insulator.
[0102] By using metallic foil films of high gas-barrier quality for both surface f ilms
, which constitute a vacuum heat insulator, a vacuum heat insulator having a high
reliability can be made use of even in the case where both surfaces of the vacuum
heat insulator are put in contact with complex-shaped surfaces. Since the both surfaces
are made of the same material, cost can be reduced. Further, since the both surfaces
are made of the same material, there is no need of caring so as not to take a stuck
surface of the vacuum heat insulator for another when the vacuum heat insulator is
stuck to outer box 12 or inner box 11, so that the work is made easy.
[0103] Preferably, the inorganic fiber aggregate, which constitutes core material 92, has
a fiber diameter in the range of 0.1 µm to 1. 0 µm to constitute a vacuum heat insulator
having a thermal conductivity about one tenth as large as the thermal conductivity
of rigid urethane foam 13. When the thermal conductivity of urethane foam 13 is 0.015
W/mK, the thermal conductivity of vacuum heat insulator 91 is 0.0015 W/mK. The thermal
conductivity of vacuum heat insulator 91 may 0.0010 W/mK to 0.0030 W/mK depending
upon selection of the fiber diameter of the inorganic fiber aggregate. That is, the
thermal conductivity may be 1/15 to 1/5 as large as the of urethane foam 13. This
is because the adiabatic performance as a composite-layer heat insulating wall serves
effectively even when vacuum heat insulator 91 is decreased in thickness so as not
to hinder flowability of urethane foam 13 in the case where the composite-layer heat
insulating wall composed of urethane foam 13 and vacuum heat insulator 91 is relatively
small in thickness. Further, this is because it is directed to having the energy-saving
effect served in an expected manner by virtue of arranging a vacuum heat insulator
also in locations, in which the wall thickness is relatively small, with a view to
realizing a high coverage.
(Eleventh Exemplary Embodiment)
[0104] Fig. 27 is an enlarged, cross sectional view showing an essential part of a refrigerator
according to an eleventh exemplary embodiment of the invention. The construction except
the above part is the same as that according to the first exemplary embodiment.
[0105] In the figure, one surface of a covering of vacuum heat insulator 79 has film 80
including an aluminum deposit layer and the other surface thereof has film 81 having
an aluminum foil. Film 80 is stuck to outer box 62. Sealed portions 82 of film 80
and film 81 are bent toward rigid urethane foam 75 to be arranged.
[0106] With such a constitution, film 80 having the aluminum deposit layer is lower in thermal
conductivity but larger in gas permeability than film 81. Film 81 having the aluminum
foil is lower in gas permeability but larger in thermal conductivity than film 80.
Accordingly, when sealed portions 82 are bent toward film 81 susceptible to thermal
conduction, that is, toward urethane foam 75, a heat transfer path to outer box 62
along film 81 is made long. A distance between sealed portions 82 and outer box 62
is increased. Thereby, heat transfer toward outer box 62 via the films is suppressed,
thus enhancing the adiabatic quality.
[0107] While the above explanation is given with the use of the films having the aluminum
deposit layer and the film having the aluminum metallic foil respectively, aluminum
may be replaced by other metals.
[0108] While this embodiment is described on the basis of the first exemplary embodiment
it can be constituted in combination with features, which are described in other embodiments.
The embodiment may be combined with features, which are described in the following
embodiments.
(Twelfth Exemplary Embodiment)
[0109] Fig. 28 is a view showing a transverse section of a refrigerator according to a twelfth
exemplary embodiment of the present invention, and Fig. 29 is a view showing, in enlarged
scale, a portion in the vicinity of a radiating pipe of the refrigerator. The fundamental
construction except the above parts is the same as that according to the first exemplary
embodiment or the ninth exemplary embodiment.
[0110] Radiating pipes 101 serving as a condenser, which constitutes a part of a refrigerating
cycle, are arranged in contact with side surfaces or a back surface of outer box 12,
and fixed to outer box 12 by aluminum tape 102 of good thermal conduction from upper
surfaces thereof. Aluminum tape 102 also serves as a sealing material. Vacuum heat
insulator 34 is arranged in a manner to cover radiating pipes 101. Aluminum tape 102
is also arranged to extend outside the refrigerator. With such a constitution, heat
from radiating pipes 101 is surely shut off by vacuum heat insulator 34 to efficiently
reduce an endothermic load into the refrigerator. Further, since aluminum tape 102
is arranged to extend outside the refrigerator, an air present between radiating pipes
101 and outer box 12 can freely move outside the refrigerator. Thereby, irregularities
and warpage of surfaces of outer box 12, which are caused by thermal contraction of
air, are suppressed, so that beauty in outward appearance is maintained. Further,
the work of sticking of radiating pipes 101 can be easily done without caring for
a quantity of air between radiating pipes 101 and outer box 12.
[0111] Further, aluminum tape 102 is preferably split midway, or formed with holes. Thereby,
an air present between radiating pipes 101 and vacuum heat insulator 34 can freely
move outside the refrigerator. Accordingly, irregularities and warpage of surfaces
of outer box 12, which are caused by thermal contraction of air, are suppressed, so
that beauty in outward appearance is maintained. Further, the work of sticking of
radiating pipes 101 can be easily done without caring for a quantity of air between
radiating pipes 101 and vacuum heat insulator 34.
[0112] It does not matter if radiating pipes 101 are beforehand assembled into vacuum heat
insulator 34 and mounted on outer box 12 when radiating pipes 101 are to be installed.
In this case, vacuum heat insulator 34 assembling radiating pipes 101 to a surface
thereof in contact with outer box 12 is arranged inside outer box 12. With such a
constitution, air gaps between radiating pipes 101 and vacuum heat insulator 34 can
be made smaller than those in the case where radiating pipes 101 are fixed to an inside
of outer box 12 before radiating pipes 101 are interposed between outer box 12 and
vacuum heat insulator 34. Accordingly, irregularities and warpage of surfaces of outer
box 12 are suppressed, so that it is possible to maintain beauty in outward appearance.
Vacuum heat insulator 34 is enhanced in adiabatic effect, so that it is possible to
enhance the effect of energy saving. Since it is possible to beforehand arrange radiating
pipes 101 on vacuum heat insulator 34 to assemble the same thereinto, manufacture
is facilitated.
[0113] With such a constitution, radiating pipes 101 are interposed between outer box 12
and vacuum heat insulator 34 to be assembled thereto, so that it is possible to surely
shut off heat of radiating pipes 101 with vacuum heat insulator 34 to efficiently
reduce an endothermic load into the refrigerator.
(Thirteenth Exemplary Embodiment)
[0114] Fig. 30 is a perspective view showing a state before a flat sheet for an outer box
of a refrigerator according to a thirteenth exemplary embodiment of the invention
is bent. The fundamental construction except the above part is the same as that according
to the first exemplary embodiment or the ninth exemplary embodiment.
[0115] Radiating pipes 101 are arranged in contact with surface 107, which will make side
surfaces of outer box 12, but radiating pipes 61 are not arranged on surface 106,
which will make a roof surface. In other words, radiating pipes 101 are arranged on
an inside of outer box 12 keeping from locations, which will correspond to the roof
surface of the refrigerator. With such a constitution, heat of radiating pipes 101
is surely shut off by vacuum heat insulator 34, so that an endothermic load into the
refrigerator is reduced. Since vacuum heat insulator 34 is superior to rigid urethane
foam 13 in adiabatic performance, a quantity of heat absorbed in the refrigerator
is reduced, so that it is possible to dispense with the provision of radiating pipes
101 onroof surface 106. Accordingly, vacuumheat insulator 32 can be easily stuck to
the roof surface, thereby enabling heightening the energy-saving effect.
[0116] Absence of radiating pipes 101 on roof surface 106 makes radiating pipes 101 simple
in configuration, thus enabling achieving an improvement in workability, reduction
in manhour, and reduction in material cost. Further, absence of radiating pipes 101
on roof surface 106 makes it possible to have the radiating pipes serving also as
ones for refrigerators, which are constructed otherwise.
(Fourteenth Exemplary Embodiment)
[0117] Fig. 31 is an enlarged view showing an essential part of a refrigerator according
to a fourteenth exemplary embodiment of the invention. The fundamental construction
except the essential part is the same as that according to the first exemplary embodiment
or the ninth exemplary embodiment.
[0118] Vacuum heat insulator 34 is arranged in contact with outer box 12, and any margin
for sealing of films is not provided on vacuum heat insulator 34 in a direction, in
which urethane foam 13 flows. In other words, vacuum heat insulator 34 is arranged
between outer box 12 and inner box 11 in a state, in which any margin for sealing
of films, on vacuum heat insulator 34 is not positioned in the direction, in which
urethane foam 13 flows. With such a constitution, stable flow is enabled without having
vacuum heat insulator 34 hindering flow of urethane foam 13.
[0119] Further, urethane foam 13 is in a highly moist state when being poured between outer
box 12 and inner box 11, and it does not contact directly with the margin for sealing
of films, so that vacuum heat insulator 34 is not subjected to thermal stress and
so prevented from being deteriorated.
[0120] Further, the margin for sealing of films is decreased, so that vacuum heat insulator
34 preserves a high gas-barrier quality.
(Fifteenth Exemplary Embodiment)
[0121] Fig. 32 is a cross sectional view showing an essential part of a refrigerator according
to a fifteenth exemplary embodiment of the invention. The construction except the
above part is the same as that according to the ninth exemplary embodiment.
[0122] Vacuum heat insulator 34A is preferentially arranged in locations, in which miscellaneous
things such as defrosting-water pipe 112, wiring (not shown), etc. are present. That
is, according to this embodiment, vacuum heat insulator 34A is arranged in locations,
in which miscellaneous things (defrosting-water pipe 72, wiring, etc.) being apt to
hinder flow of rigid urethane foam 13 are present, between outer box 12 and inner
box 11. With such a constitution, vacuum heat insulator 34A effectively restricts
an endothermic load in the refrigerator and so the energy-saving effect is heightened.
The adiabatic performance is ensured by arranging vacuum heat insulator 34A in locations,
in which miscellaneous things being apt to hinder flowability of urethane foam 13
are present.
[0123] Preferably, defrosting-water pipe 112 is preferably installed between vacuum heat
insulator 34A and outer box 12. With such a constitution, vacuum heat insulator 34A
keeps defrosting water warm to prevent the same from being cooled and frozen under
the influence of temperature inside freezing rooms 18A, 19.
(Sixteenth Exemplary Embodiment)
[0124] Fig. 33 is a cross sectional view showing an essential part of a refrigerator according
to a sixteenth exemplary embodiment of the invention. The construction except the
above part is the same as that according to the first exemplary embodiment or the
ninth exemplary embodiment.
[0125] According to this embodiment, protective members 113, which protect end surfaces
of outer box 12, also serve as positioning members at the time of sticking of vacuum
heat insulator 34. That is, protective members 113 provided on the end surfaces of
outer box 12 so as to protect end surfaces of vacuum heat insulator 34 are used to
position vacuum heat insulator 34. In this manner, protective members 113 on the end
surfaces of outer box 12 and positioning members for vacuum heat insulator 34 are
used in common to each other. Thereby, damage to vacuum heat insulator 34 at the time
of assembly is prevented. Further, positioning at the time of sticking of vacuum heat
insulator 34 is made easy to improve the workability.
[0126] Protective members 113 may be provided on a roof plate to protect end surfaces of
vacuum heat insulator 32 and serve as positioning members at the time of assembly.
(Seventeenth Exemplary Embodiment)
[0127] Fig. 34 is a view showing a structure of a vacuum heat insulator applied to a refrigerator
according to a seventeenth exemplary embodiment of the invention. Unlike core material
92 in the tenth exemplary embodiment, core material 121 is made of an inorganic fiber
aggregate, which is formed by a binding agent to be plate-shaped. A material making
the inorganic fiber aggregate is not specifically limitative but formed by using an
organic or inorganic binding agent to form an inorganic fiber such as glass wool,
ceramic fiber, rock wool, etc., in the form of a plate.
[0128] Gas-barrier film 122 is formed by sealed portions 123 to make a bag. An interior
of gas-barrier film 122 is kept gas tight. Amaterial composition of the film is not
specifically limitative. The film is composed in the same manner as, for example,
deposited layer film 93 and metallic foil layer film 97 in the tenth exemplary embodiment.
More specifically, one has a plastic laminate film, which includes an outermost layer
of polyethylene terephthalate resin, an intermediate layer of aluminum foil, and an
innermost layer of high-density polyethylene resin. The other has, for example, a
plastic laminate film, which includes an outermost layer of polyethylene terephthalate
resin, an intermediate layer of ethylene-vinyl alcohol copolymer resin having a deposited
aluminum layer, and an innermost layer of high-density polyethylene resin. These are
formed to make a bag.
[0129] A method of manufacturing a vacuum heat insulator has inserting a core material into
gas-barrier film 122 in the form of a bag, vacuumizing an interior of the bag, and
sealing an opening by fusing seal 124 to maintain the interior thereof vacuum.
[0130] Figs. 35 and 36 are a side, cross sectional view and a front, cross sectional view,
respectively, showing the refrigerator according to this embodiment. The fundamental
construction is the same as that according to the ninth exemplary embodiment, and
vacuum heat insulators 34 arranged inside the outer box on the sides are extended
to a cold storage region in Fig. 36. In place of vacuum heat insulators 34A arranged
outside the inner box on the sides, vacuum heat insulators 34B are provided to be
arranged in contact with inner box 11 on lower portions of sides of adiabatic box
10A corresponding to freezing room 19. Vacuum heat insulators 34 and vacuum heat insulators
34B are arranged with areas between opposed end surfaces thereof being positioned
in the vicinity of an upper end surface of machine room 20. Lower ends of vacuum heat
insulators 34 are positioned below upper ends of vacuum heat insulators 34B. Such
a constitution serves the adiabatic effect on the side in the same manner as in the
ninth exemplary embodiment. That is, positions, in which the lower ends of vacuum
heat insulators 34 and the upper ends of the vacuum heat insulators arranged outside
the inner box on the side overlap each other, are not limitative. Vacuum heat insulators
34, 34B are provided in a partitioning adiabatic section between machine room 20,
in which compressor 21 is accommodated, and an interior of the refrigerator. The temperature
inside the refrigerator is -20 °C in freezing room 19 and 40 to 50 °C in machine room
20. That is, vacuum heat insulators 34, 34B efficiently insulate a thick wall portion
between machine room 20 and an interior of freezing room 19, between which temperature
difference is relatively large. Further, in pouring rigid urethane foam 13 into adiabatic
box 10A, it is common that a front opening of adiabatic box 10A is positioned downward.
A raw liquid of urethane foam 13 is poured from urethane pouring ports in two locations
substantially centrally in a heightwise direction of left and right back surfaces
of adiabatic box 10A. Flow of urethane foam 13 thus foamed spreads in a sectorial
manner about locations just below the urethane pouring ports in two locations. Urethane
foam 13 finally reaches a roof surface and a bottom surface of adiabatic box 10A and
constituent surfaces of machine room 20. According to this embodiment, vacuumheat
insulator 36 having a high degree of flatness is arranged on the constituent surfaces
of machine room 20, which urethane foam 13 finally reaches. Therefore, it is possible
to surely ensure spatial dimensions in the vicinity of locations, which urethane foam
13 finally reaches, so that urethane foam 13 is enhanced in filling quality to enable
ensuring a predetermined adiabatic performance.
[0131] Adiabatic box 10A is the same as that in the first exemplary embodiment with respect
to adiabatic wall thickness and coverage relative to outer surfaces of refrigerator
10, and so an explanation therefor is omitted.
[0132] Vacuum heat insulators 32, 33, 34, 34B, 35, 36, 37, 38, 39, 40, and 41 are formed
as described above by covering an inorganic fiber aggregate, which is formed from
core material 121 with a binding agent to be plate-shaped, with gas-barrier film 122
and vacuumizing an interior thereof. The vacuum heat insulators together with urethane
foam 13 construct adiabatic box 10A.
[0133] The vacuum heat insulator shown in Fig. 34 may be applied to other embodiments.
[0134] Vacuum heat insulators 34B, 35, and 36 may be made by beforehand molding core material
121 by a binding agent to follow a shape of surfaces in contact with inner box 11.
By virtue of such molding, spatial layers (voids) are not produced on contact surfaces
of inner box 11 and vacuum heat insulators 34B, 35, 36. Therefore, warpage of inner
box 11 or the like is prevented, so that it is possible to heighten the quality in
outward appearance.
[0135] Preferably, vacuum heat insulators 32, 33, 34, 34B, 35, 36, 37, 38, 39, 40, and 41
have a bend elastic constant of 40 to 64 MPa in a testing method in conformity with
Japanese Industrial Standards JIS-K7221. The bend elastic constant is a ratio of a
bending stress within a bending proportional limit to a corresponding strain. Since
urethane foam 13 has a bend elastic constant of the order of 8 MPa, the vacuum heat
insulators preferably have a bend elastic constant five to eight times that of the
urethane foam.
[0136] TABLE 1 indicates results of strength tests on adiabatic boxes making use of vacuum
heat insulators having different bend elastic constants. The tests are carried out
such that displacements of uppermost portions of sides of adiabatic box 10A in a horizontal,
longitudinal direction are measured when a food load of about 30 kg is accommodated
in cold storage room door 27.
TABLE 1
|
SAMPLE A |
SAMPLE B |
SAMPLE C |
SPECIFICATIONS OF ADIABATIC BOX |
ONLY RIGID URETHANE FOAM |
VACUUM HEAT INSULATOR + RIGID URETHANE FOAM |
VACUUM HEAT INSULATOR + RIGID URETHANE FOAM |
BEND ELASTIC CONSTANT OF VACUUM HEAT INSULATOR |
- |
20 MPa |
40 MPa |
DEFORMATION OF SIDES OF ADIABATIC BOX |
3 mm |
4 mm |
3 mm |
[0137] The above results reveal that the strength of adiabatic box 10A is equal to or less
than that of only a vacuum heat insulator (A) in the case where rigid urethane foam
and a vacuum heat insulator having a bend elastic constant of the order of 40 MPa
or less make a dual layer. This is because an adiabatic wall is not of a single structure
but of a dual-layered structure to be decreased in bend elastic constant. A vacuum
heat insulator having a bend elastic constant of 40 MPa or more is used to provide
a dual-layered structure having a larger bend elastic constant than that of only rigid
urethane foam. Since rigid urethane foam has a bend elastic constant of 8 MPa, the
adiabatic box of dual-layered structure is made equal to or more in strength than
that of the single structure by making the bend elastic constant of a vacuum heat
insulator five times or more as large as that of the rigid urethane foam.
[0138] An increase of a vacuum heat insulator in bend elastic constant is realized by selecting
a binding agent in forming an inorganic fiber aggregate of core material 121 into
a plate configuration, or increasing an amount of use of such binding agent. Such
measures lead to an increase in cost. Therefore, the bend elastic constant of a vacuum
heat insulator has an upper limit of the order of 64 MPa in terms of cost performance.
That is, when the bend elastic constant of a vacuum heat insulator is five times or
more but eight times or less as large as that of rigid urethane foam, the strength
of an adiabatic box of dual-layered structure can be made equal to or more than that
of only rigid urethane foam while meeting with cost performance.
[0139] A vacuum heat insulator having such bend elastic constant is manufactured by covering
an inorganic fiber aggregate, which is formed from core material 121 with a binding
agent to be plate-shaped, with gas-barrier film 122 and vacuumizing an interior thereof.
As compared with a vacuum heat insulator having a core material made of only an inorganic
fiber aggregate, a vacuum heat insulator is increased in pressure capacity, bending
strength, and flatness when an inorganic fiber aggregate is bonded and formed by a
binding agent. Accordingly, in case of using such vacuum heat insulator, adiabatic
box 10A is increased in strength. Such a vacuum heat insulator can be assembled into
adiabatic box 10A with a high degree of flatness maintained, so that it is possible
to surely ensure dimensions of a space, in which urethane foam 13 being formed inside
adiabatic box 10A flows. Thereby, flowability is increased when urethane foam 13 is
poured, urethane foam 13 is increased in filling ratio, and a predetermined adiabatic
performance is obtained.
[0140] Since vacuum heat insulators 32, 33, 34, 34B, 35, 36, 37, 38, 39, 40, and 41 are
enhanced in flatness, it is possible to eliminate spatial portions defined between
them and surfaces, with which they contact directly via adhesives. As a result, the
vacuum heat insulators are increased in adhesiveness to the bonded surfaces, so that
it is possible to prevent coming-off and fall of vacuum heat insulators at the time
of manufacture and assembly, which leads to enhancement in reliability and workability.
Further, since the vacuum heat insulators are enhanced in flatness, surfaces of adiabatic
box 10A in direct contact with them are also increased in flatness, and refrigerator
10 has a high quality in outward appearance.
[0141] Since the vacuum heat insulators are increased in strength, the vacuum heat insulators
are easily taken out at the time of scrapping and disassembling after the use of an
associated refrigerator, which leads to an improvement in recycling quality.
[0142] When vacuum heat insulators 32, 33, 34, 34B, 35, 36, 37, 38, 39, 40, and 41 are bonded
and fixed to inner box 11, outer box 12 or outer plates of doors, adhesives are preferably
coated on whole bond surfaces by means of a roller. As adhesives, hot melt made of,
for example, rubber base materials are used.
[0143] TABLE 2 indicates results of adhesive strength tests on vacuum heat insulators and
outer box 12 in the case where coating specifications of adhesives are changed. The
tests are carried out such that 180-degrees peel adhesion is found in this test for
test sheets set to 25 mm in width in conformity with Japanese Industrial Standards
JIS-Z0237(8).
TABLE 2
|
SAMPLE D |
SAMPLE E |
COATING SPECIFICATIONS OF ADHESIVES |
WHOLE SURFACE COATING |
LINEAR COATING OF 10 mm IN WIDTH (BOND-SURFACE AREA RATIO 40 %) |
180° PEEL ADHESION (N/25 mm WIDTH) |
30N |
16N |
[0144] Rubber base hot melt is used for adhesives, and stainless, to which polyethylene
terephthalate was laminated, is used for test substrate. A coating thickness of adhesives
is 30 µm, pressure at the time of bonding is 2 kg, and a roller is caused to reciprocate
once. Ambient temperature in the test is 23 °C.
[0145] It is found from results in TABLE 2 that adhesive strength is increased to become
substantially twice as large as that of SAMPLE E in the case where adhesives were
linearly coated at predetermined intervals in conventional methods.
[0146] By doing in this manner, vacuum heat insulators 32, 33, 34, 34B, 35, 36, 37, 38,
39, 40, and 41 do not come off and fall in the manufacturing process. The vacuum heat
insulators are firmly bonded and fixed to inner box 11 or outer box 12 whereby adiabatic
box 10A is increased in strength. Owing to whole-surface coating of adhesives, no
spaces are generated on bonded surfaces of the respective vacuum heat insulators and
inner box 11 or outer box 12, and warpage is not generated on adiabatic box 10A, thus
enabling heightening the quality in outward appearance.
[0147] Vacuum heat insulators 32, 33, 34, 38, 39, 40, and 41 are arranged in contact with
outer box 12. Since the vacuum heat insulators having a high degree of flatness are
arranged on outer box 12, which defines flat surfaces, and adhesives are applied to
contact surfaces, no spatial layers (voids) are generated on contact surfaces of outer
box 12 and the vacuum heat insulators. Thereby, warpage or the like is prevented from
being generated on outer box 12, thus heightening the quality in outward appearance.
[0148] Since vacuum heat insulators 34B, 35, and 36 are arranged in contact with inner box
11, condensing of a foaming agent of urethane foam 13 disposed on a side of outer
box 12 is suppressed to lead to an increase of adiabatic walls in adiabatic performance.
[0149] Vacuum heat insulators 33, 35, 34, 34B, and 36 are provided inside those adiabatic
walls, which correspond to a freezing temperature zone. Thereby, adiabatic box 10A
corresponding to a freezing temperature zone, which is relatively large in temperature
difference relative to an outside of the refrigerator, can be efficiently heightened
in adiabatic performance.
[0150] In order to heighten the adiabatic performance while ensuring an internal volume
of adiabatic box 10A, it is important to ensure maximally a thickness of vacuum heat
insulators on those adiabatic wall portions of adiabatic box 10A, which involve large
temperature differences, while ensuring spaces, through which urethane foam 13 flows.
According to this embodiment, since core material 121 is made of an inorganic fiber
aggregate, which is formed by a binding agent to be plate-shaped, vacuum heat insulators
33, 35, 34, 34B, and 36 have a high degree of flatness. Accordingly, thicknesses of
vacuum heat insulators 33, 35, 34, 34B, 36 can be ensured maximally on those adiabatic
wall portions of freezing rooms 18A, 19, which involve large temperature differences,
while ensuring dimensions of spaces,
in which urethane foam 13 flows. Accordingly, it is possible to provide a refrigerator
having a high adiabatic performance.
[0151] Vacuum heat insulators 38, 39, 40, and 41 are provided on the outer plates inside
those adiabatic walls, which constitute respective doors 27, 28, 29, 30 provided on
openings on a front surface of the refrigerator. In this manner, vacuum heat insulators
38, 39, 40, 41 having a high degree of flatness are provided on those outer plates,
which constitute respective doors 27, 28, 29, 30, whereby no spatial layers (voids)
are generated on contact surfaces of the outer plates of the respective doors and
the respective vacuum heat insulators. Therefore, warpage or the like is prevented
from being generated on outer box 12, thus heightening the quality in outward appearance.
[0152] According to this embodiment, hydrocarbon, for example, cyclopentane is used as a
foaming agent for urethane foam 13. This leads to global environmental protection
and prevention of warming as compared with conventional chlorofluorocarbon base foaming
agents. Since the vacuum heat insulators are made of a noncombustible inorganic fiber
aggregate, safety is high even in case of using a combustible hydrocarbon base foaming
agent. The high adiabatic performance of the vacuum heat insulators compensate for
degradation in adiabatic performance due to application of hydrocarbon base foaming
agents, thus heightening the adiabatic performance of the adiabatic box.
[0153] According to this embodiment, hydrocarbon, for example, isobutane, being a combustible
natural refrigerant is used for a refrigerant in a refrigerating cycle composed of
compressor 21, condenser 26, refrigerating cooler 22, and freezing cooler 24. Thereby,
this leads to global environmental protection and prevention of warming as compared
with conventional chlorofluorocarbon base refrigerants. Since vacuum heat insulators
are made of a noncombustible inorganic fiber aggregate, safety is high even in case
of using hydrocarbon being a combustible refrigerant.
[0154] It is described in the refrigerator according to the present embodiment that the
vacuum heat insulators are fixed in contact with inner box 11, outer box 12, or outer
plates of the respective doors and urethane foam 13 is foamed in spaces therein. However,
the vacuum heat insulators may be arranged intermediate between inner box 11 and outer
box 12 and urethane foam 13 may be foamed in the spaces therebetween as in the first
exemplary embodiment. In this case, core material 121 of the vacuum heat insulators
is made of an inorganic fiber aggregate, which is formed by a binding agent to be
plate-shaped, and the vacuumheat insulators have ahighdegree of flatness. Therefore,
it is possible to ensure dimensions of spaces between inner box 11 or outer box 12
and the vacuum heat insulators with high accuracy, so that urethane foam 13 can be
surely filled. Because of no direct contact with inner box 11 and outer box 12, adiabatic
box 10A is not marred in outward appearance. Since the vacuum heat insulators are
arranged intermediate between inner box 11 and outer box 12 and surrounded circumferentially
by urethane foam 13, fixation of the vacuum heat insulators by means of adhesives
or the like is unnecessary.
[0155] Vacuum heat insulators, in which core material 121 is beforehand formed by a binding
agent to be L-shaped, may be arranged on corner portions of a roof surface and side
surfaces of refrigerator 10. In this case, the coverage of the vacuum heat insulators
relative to adiabatic box 10A can be further increased. Adiabatic box 10A can be efficiently
increased in strength by arranging vacuum heat insulators of high bending strength
on corner portions of adiabatic box 10A.
[0156] It is described in this embodiment that vacuum heat insulators 38, 39, 40, and 41
being arranged inside respective doors 27, 28, 29, 30 disposed on the openings on
the front surface of refrigerator 10 contact with outer plates of the respective doors.
However, vacuum heat insulators 38, 39, 40, 41 may be arranged in portions of the
respective doors intermediate between the inner box and the outer plates and urethane
foam 13 may be filled in the spaces in the same manner as in the first exemplary embodiment.
In this case, vacuum heat insulators 38, 39, 40, and 41 have a high degree of flatness,
dimensions of spaces, into which urethane foam 13 is filled, can be surely ensured,
and urethane foam 13 is surely filled. Since the outer plates and vacuum heat insulators
38, 39, 40, 41 do not contact directly with each other, it is possible to further
suppress deformation of surfaces of the outer plates of the respective doors.
(Eighteenth Exemplary Embodiment)
[0157] Fig. 37 is a circuit diagram of a refrigerating cycle of a refrigerator according
to an eighteenth exemplary embodiment of the present invention. The construction except
the refrigerating cycle is the same as that according to the first exemplary embodiment.
An explanation will be given below with reference to Figs. 37 and 2.
[0158] Refrigerant discharge port 138A of compressor 138 is connected through condenser
139 to an inlet of three-way switching valve 140, which constitutes a flow-passage
switching portion. One of outlets of switching valve 140 is connected through freezing
capillary 141 to an inlet of evaporator 136 for the freezing room(referred below to
as evaporator 136). An outlet of evaporator 136 is connected through accumulator 142
to an inlet of check valve 143. An outlet of check valve 143 is connected to refrigerant
inflow inlet 138B of compressor 138. Another outlet of switching valve 140 is connected
through cold storage capillary 144 to an inlet of evaporator 134 for the cold storage
room(referred below to as evaporator 134). An outlet of evaporator 134 is connected
to the outlet of check valve 143. That is, evaporator 134 and evaporator 136 are connected
in parallel according to compressor 138, and the outlet of evaporator 136 is connected
through check valve 143 to the outlet of evaporator 134.
[0159] An outline of an action and an effect thereof in the above constitution is illustrated
as follows. First, in a state, in which compressor 138 is driven, switching valve
140 switches over a refrigerant flow passage so that a refrigerant discharged from
compressor 138 flows to evaporator 134 for the cold storage room. That is, a state
indicated by a broken line arrow 150 in Fig. 37 turns up. Subsequently, this state
is called a cold storage mode. In the cold storage mode, the refrigerant discharged
from compressor 138 undergoes a known phase change and thereafter is fed to evaporator
134 to cool an air around evaporator 134. Evaporator 134 shown in Fig. 37 corresponds
to cooler 22 shown in Fig. 2. At this time, an air cooled by evaporator 134 is fed
to cold storage room 15 and vegetable room 16 by virtue of the blasting action of
refrigerating fan 23 to cool cold storage room 15 and vegetable room 16.
[0160] The refrigerant flow passage is switched over so that the refrigerant discharged
from compressor 138 by switching valve 140 in a state, in which compressor 138 is
driven, flows to evaporator 136. That is, a state indicated by a solid line arrow
151 in Fig. 37 is brought about. Subsequently, this state is called a freezing mode.
In the freezing mode, the refrigerant discharged from compressor 138 undergoes a known
phase change and thereafter is fed to evaporator 136 to cool an air around evaporator
136. Evaporator 136 shown in Fig. 37 corresponds to cooler 24 shown in Fig. 2. At
this time, the air cooled by evaporator 136 is fed to changeover room 17, ice making
room 18, and freezing room 19 by virtue of the blasting action of freezing fan 25.
[0161] In this manner, a cold storage temperature zone space composed of cold storage room
15 and vegetable room 16 and a freezing temperature zone space composed of changeover
room 17, ice making room 18, and freezing room 19, respectively, are cooled independently.
Therefore, evaporator 14 maintains a cooling temperature of the order of -5 °C and
evaporator 16 maintains a cooling temperature of the order of -25 °C whereby temperatures
in the rooms to be suited to respective cooling spaces are efficiently provided. Accordingly,
the energy-saving effect is heightened. Since the cold storage temperature zone space
and the freezing temperature zone space are cooled independently in a time-sharing
manner, a quantity of heat, which should be removed at a time, is decreased. Therefore,
condenser 139 is decreased in quantity of heat as radiated. As a result, a volume
for piping in the circuit diagram of the refrigerating cycle is decreased to some
extent. Accordingly, in case of using a hydrocarbon base natural refrigerant for the
refrigerant, the danger of ignition at the time of refrigerant leakage is suppressed
to some degree.
[0162] Further, in the case where compressor 18 is stopped in a state, in which both the
cold storage temperature zone space and the freezing temperature zone space is cooled
to preset temperatures, compressor 138 is stopped in a state of the cold storage mode.
In the cold storage mode, switching valve 140 acts to put refrigerant discharge port
138A of compressor 138 and the inlet of evaporator 134 in a communicated state, and
refrigerant discharge port 138A and the inlet of evaporator 136 are shut off therebetween.
When compressor 138 is stopped in this state, there is no inflow into evaporator 136
from a high-pressure side typified by condenser 139. Further, check valve 143 acts
to prevent the refrigerant from counterflowing to evaporator 136 from evaporator 134.
Accordingly, the refrigerant at low temperature is held in evaporator 136, so that
evaporator 136 is prevented from rising in temperature unnecessarily. Thereby, loss
in energy in the refrigerating cycle is further decreased, so that the effect of energy
saving is enhanced.
[0163] Conventional refrigerators generally use R134a as a refrigerant. On the other hand,
the refrigerator according to this embodiment can use R600a isobutane as a hydrocarbon
base natural refrigerant in the same manner as in the seventeenth exemplary embodiment.
[0164] With the above constitution, an endothermic quantity of the whole refrigerator is
sharply reduced as compared with the case where thermal insulation of refrigerator
10 and doors 27, 28, 29, 30, 31 is achieved only by rigid urethane foam 13. As a result,
the effect of energy saving resulted from reduction in endothermic quantity of the
box is produced. Further, temperature fluctuation with time in the room under suspension
is decreased also in the case where the cold storage temperature zone space and the
freezing temperature zone space are alternately cooled by the parallel switchover
system. That is, the parallel switchover system can enhance the cooling efficiency
and heighten the effect of energy saving as well as heighten the freshness preserving
quality of food.
[0165] By using the vacuum heat insulators to decrease the endothermic quantity of the box,
a quantity of heat, which should be removed at a time, and a corresponding quantity
of released heat are decreased as compared with the case where thermal insulation
of the box is achieved only by rigid urethane foam. Therefore, the volume for piping
is decreased. With conventional adiabatic boxes with rigid urethane foam, a radiation
piping (not shown), which constitutes a part of condenser 139, is embedded in rigid
urethane foam with a view to preventing dew condensation on surfaces of the refrigerator.
According to the present embodiment, by using vacuum heat insulators for those portions,
which possible undergo dew condensation, a radiation piping designed for prevention
of dew condensation is made unnecessary. Therefore, the volume for piping is sharply
decreased as a whole. As a result, an amount of refrigerant required for cooling is
sharply reduced, so that in case of using a combustible hydrocarbon base natural refrigerant,
the danger of ignition is exceedingly reduced even if the refrigerant should leak.
[0166] While the effect described above is obtained even in the case where compressor 138
is of constant revolution type, it is preferable to use a compressor of variable revolution
type as compressor 138 to constitute a refrigerating cycle. With such a constitution,
a difference between a static endothermic load when the box is stabilized by the use
of vacuum heat insulators, and a maximum load when doors are opened and closed and
food load is charged into rooms can be controlled by the number of revolutions of
the compressor. It is necessary in a compressor of constant revolution type to ensure
an excessive cylinder volume in conformity with a maximum load, and time, during which
the compressor is stopped, is increased when the compressor is stable, so that temperature
fluctuation in rooms with time becomes considerable. On the other hand, when a compressor
of variable revolution type are applied, such loss in effect of energy saving is decreased
and temperature fluctuation in rooms with time is suppressed. Since the cylinder volume
is made small, design with a further less amount of refrigerant is made possible.
Therefore, even in the case where a combustible hydrocarbon base refrigerant should
leak outside the cooling system, the danger involved in the combustible refrigerant
is exceedingly reduced.
[0167] Coverage of vacuum heat insulators and design of adiabatic wall thickness of a refrigerator
are the same as those in the other embodiments, and so an explanation therefor is
omitted.
[0168] Fig. 38 is a view showing a structure of a vacuum heat insulator. The fundamental
construction is the same as that according to the tenth exemplary embodiment. In Fig.
38, core material 145 is made of an inorganic fiber aggregate 145 of glass wool or
the like. The vacuum heat insulator is formed by inserting core material 145 into
a covering, in which metallic foil layer film 146A and deposited layer film 146B are
stuck together, vacuumizing an interior of the covering, and sealing an opening. Since
materials for and coefficients of thermal conductivity of core material 145 and films
146A, 146B are the same as those according to the tenth exemplary embodiment, an explanation
therefor is omitted.
[0169] With such a constitution, there is obtained a vacuum heat insulator having an adiabatic
performance about ten times as large as that of rigid urethane foam. Therefore, the
effect of reduction in endothermic quantity of the box is sharply heightened in case
of using vacuum heat insulators. As a result, the effect of energy saving is sharply
enhanced, temperature fluctuation in rooms with time is decreased even in case of
using a parallel switchover system, and the freshness preserving quality of food is
improved. Owing to further reduction in endothermic quantity, a necessary amount of
refrigerant is restricted to be further small, and a possible danger at the time of
leakage of a refrigerant is further decreased even when combustible isobutane is used
as the refrigerant. The inorganic fiber aggregate used for core material 145 is flame-retardant,
so that safety in the case where refrigerator 10 would be ignited is enhanced as compared
with a constitution composed only of rigid urethane foam.
[0170] Fig. 39 is a schematic view showing avacuumheat insulator. Thickness 149 of the vacuum
heat insulator is 15 mm. That is, the vacuum heat insulator is arranged in a state,
in which a surface defined by two sides 147, 148 is oriented in a direction perpendicular
to a direction, in which heat being insulated passes. Here, sides 147, 148 preferably
have lengths of 200 mm or longer. With such a constitution, the following effect is
produced.
[0171] Both gas-barrier films 146A, 146B, which constitute the covering of the vacuum heat
insulator, have a metallic film layer, so that a so-called heat bridging phenomenon
due to heat transfer occurs. Therefore, when sides 147, 148 defining a covered area
of the vacuum heat insulator are too small in length, it is not possible to bring
out the primary adiabatic performance of the vacuum heat insulator, so that the adiabatic
effect is decreased relative to an amount of vacuum heat insulator as used. On the
other hand, sides 147, 148 having lengths of 200 mm or longer make it possible to
bring out the primary adiabatic performance of the vacuum heat insulator. That is,
it has been confirmed by experiments that heat leakage is suppressed by heat bridge.
Based on the above, the primary adiabatic performance of the vacuum heat insulator
can be brought out by making lengths of two sides, except one in a thicknesswise direction,
among three sides, which define the vacuum heat insulator, 200 mm or longer. As a
result, the vacuum heat insulator is made use of in a state of high cost performance,
so that the entire refrigerator is effectively reduced in endothermic quantity. As
a result, it is possible to further enhance the effect of energy saving, the improved
freshness preserving quality of food owing to reduction of temperature fluctuation
in rooms with time, and the danger decreasing effect at the time of leakage of a refrigerant
produced by lessening of a refrigerant, in the embodiments described above.
[0172] While thickness 149 of the vacuum heat insulator is made 15 mm, an appropriate adiabatic
performance is served in the range of around 5 to 20 mm without the possibility of
hindering the foaming and filling quality of urethane foam 13.
[0173] The present embodiment is the same as the first exemplary embodiment except the configuration
of the refrigerating cycle and dimensions of the vacuumheat insulator. Such a configuration
is effective in application to those in the other embodiments.
[0174] While the embodiments of the invention have been described above, a refrigerator,
which is good in attractiveness and excellent in adiabatic performance, can be obtained
in all the embodiments. The configuration peculiar to the respective embodiments can
be embodied in combination with the remaining embodiments if possible, and such combination
falls under the category of the invention.
Industrial Applicability
[0175] According to the present invention, a refrigerator having resin foam and a vacuum
heat insulator between an outer box and an inner box adopts any one of the following
constitutions whereby it is possible to provide a refrigerator having an outward appearance,
which is good in attractiveness, and effecting an efficient heat insulation.
(1) An outer surface of an outer box, on which the vacuum heat insulator is arranged,
is set to have a center line average roughness (Ra) of 0.1 µm or more. Alternatively,
the outer surface of the outer box is set to have a glossiness of 80 or less.
(2) The Vacuum heat insulator being arranged on a door, which constitute a front surface,
is stuck to an inner plate of the door.
(3) An intermediate member is provided between the vacuum heat insulator and the outer
box to prevent deformation of the outer surface of the outer box.
(4) A radiating pipe is provided between the vacuum heat insulator and the outer box,
and an air gap defined by the vacuum heat insulator and the radiating pipe is made
to be communicated to outside.
(5) Small hole is provided on the outer box, on the surface of which is provided the
vacuum heat insulator.
(6) A machine room is provided in a lower portion, and the vacuum heat insulators
are arranged on both side surfaces of an upper portion, a roof surface, a back surface,
and a front surface of a refrigerator to contact with the outer box, and on a bottom
surface and both side surfaces of the lower portion of the refrigerator, and surfaces,
which define the machine room, to contact with an inner box.
(7) The vacuum heat insulator having a radiating pipe assembled into a surface thereof,
which contact with the outer box, is arranged inside the outer box.
1. A refrigerator comprising:
an outer box,
an inner box, and
resin foam and a vacuum heat insulator between the outer box and the inner box;
wherein the vacuum heat insulator is arranged in contact with the outer box, and
an outer surface of the outer box, on which the vacuum heat insulator is arranged,
adopt one of the following configurations,
A) a center line average roughness (Ra) of 0.1 µm or more, and
B) a glossiness of 80 or less.
2. A refrigerator comprising:
an outer box,
an inner box,
resin foam and a vacuum heat insulator between the outer box and the inner box, and
a door defining a front surface, the door having an inner plate;
wherein the vacuum heat insulator arranged on the door are stuck to the inner
plate of the door.
3. The refrigerator according to claim 2, wherein the vacuum heat insulator arranged
on the door is stuck to forefront portion of the inner plate of the door.
4. A refrigerator comprising:
an outer box,
an inner box,
resin foam and a vacuum heat insulator between the outer box and the inner box, and
an intermediate member provided between the vacuum heat insulator and the outer box
to prevent deformation of an outer surface of the outer box.
5. The refrigerator according to claim 4, wherein the intermediate member is larger than
the vacuum heat insulator.
6. The refrigerator according to claim 4, wherein the intermediate member is made of
a soft member softer than the vacuum heat insulator.
7. The refrigerator according to claim 6, wherein the soft member is made of resin foam.
8. The refrigerator according to claim 6, wherein the soft member comprises independent
foam.
9. The refrigerator according to claim 6, wherein the soft member has a thickness of
at least the flatness of the vacuum heat insulator and at most the thickness of the
vacuum heat insulator.
10. The refrigerator according to claim 4, wherein the intermediate member is made of
a hard member harder than the vacuum heat insulator.
11. The refrigerator according to claim 4, wherein the intermediate member comprises a
hard member harder than the vacuum heat insulator and a soft member softer than the
vacuum heat insulator.
12. The refrigerator according to claim 11, wherein the hard member and the soft member
in the intermediate member are arranged in this order from a side of the outer box.
13. A refrigerator comprising:
an outer box,
an inner box,
resin foam and a vacuum heat insulator between the outer box and the inner box, and
a radiating pipe provided between the vacuum heat insulator and the outer box;
wherein an air gap defined between the vacuum heat insulator and the radiating
pipe is communicated to outside the refrigerator.
14. The refrigerator according to claim 13, a flat surface of the vacuum heat insulator
opposed to the radiating pipe is provided with a groove.
15. The refrigerator according to claim 13, further comprising a fixing member to fix
thereto the radiating pipe;
wherein the fixing member has one end thereof positioned outside the refrigerator
and the other end thereof positioned inside end of the vacuum heat insulator.
16. A refrigerator comprising:
an outer box,
an inner box,
resin foam and a vacuum heat insulator between the outer box and the inner box;
wherein the vacuum heat insulator is arranged on the outer box, and a surface
of the outer box on which the vacuum heat insulator are arranged are provided with
a small hole.
17. A refrigerator comprising:
an outer box,
an inner box,
resin foam and vacuum heat insulators between the outer box and the inner box, and
a machine room in a lower portion;
wherein the vacuum heat insulators are arranged on both side surfaces of an upper
portion, a roof surface, a back surface, and a front surface to contact with the outer
box, and on a bottom surface, both side surfaces of the lower portion, and surfaces
which define the machine room to contact with an inner box.
18. The refrigerator according to claim 17, wherein whole surfaces of the vacuum heat
insulators arranged in contact with the inner box, which contact with the inner box,
contact with respective surfaces of the inner box with which the vacuum heat insulator
are arranged in contact.
19. The refrigerator according to claim 17, wherein surfaces of the inner box with which
the vacuum heat insulators are arranged in contact, has a step in contact with an
outer peripheral end surface of each of the vacuum heat insulators arranged in contact
with the inner box.
20. The refrigerator according to claim 17, further comprising
a cooler, and
a heat insulator formed at an upper surface thereof with an inclined configuration
and having a flat lower surface in close contact with the inner box, the heat insulator
being provided below the cooler.
21. The refrigerator according to claim 17, further comprising cooler;
wherein the inner box has an inclined portion disposed below the cooler, and a
heat insulator is disposed for filling up a gap defined between the inclined portion
and the vacuum heat insulator arranged in contact with the inner box.
22. The refrigerator according to claim 17, wherein the inner box has a back surface provided
with an air vent hole for the resin foam.
23. The refrigerator according to claim 17, wherein lower ends of the vacuum heat insulators
arranged in contact with the outer box on both upper side surfaces of the refrigerator
are positioned to be lower than upper ends of the vacuum heat insulators arranged
in contact with the inner box on both lower side surfaces of the refrigerator.
24. The refrigerator according to claim 17, wherein the vacuum heat insulators has a first
surface composed of metal deposited layer film and a second surface composed of film
including a metallic foil, and a sealed surface at which respective outer peripheral
portions of the first surface and the second surface are sealed, is disposed in the
same plane as the first surface.
25. The refrigerator according to claim 24, wherein the first surface is arranged in contact
with an inside of the outer box.
26. The refrigerator according to claim 24, wherein the first surface is arranged in contact
with an outside of the inner box.
27. The refrigerator according to claim 13, further comprising a sealing material for
fixing the radiating pipe to an inside of the outer box and is extended to outside
the refrigerator.
28. The refrigerator according to claim 27, wherein the sealing material is at least either
split or provided with a hole.
29. The refrigerator according to claim 27 , wherein the radiating pipe is arranged on
an inside of the outer box keeping from a roof surface of the refrigerator.
30. A refrigerator comprising:
an outer box,
an inner box,
resin foam and a vacuum heat insulator between the outer box and the inner box, and
a radiating pipe assembled into the vacuum heat insulator arranged inside the outer
box.
31. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30,
wherein both surfaces of the vacuum heat insulator are composed of film having
a metallic foil.
32. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30,
wherein the vacuum heat insulator has a film sealing margin, the film sealing margin
being arranged in a direction except a direction in which the resin foam flows.
33. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30,
wherein the vacuum heat insulator has a core material containing an inorganic fiber
aggregate, which is formed by a binding agent to be plate-shaped, and a gas-barrier
film to cover the core material.
34. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30, further
comprising an adhesive coated on whole surfaces, at which the vacuum heat insulator
and one of the inner box and the outer box contact with each other.
35. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30,
wherein a foaming agent for the resin foam contains hydrocarbon.
36. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30 further
comprising:
at least one of a cold storage room and a freezing room within the inner box,
a cooler to cool at least of one of the cold storage room and the freezing room, and
a refrigerant used for the cooler and composed of hydrocarbon.
37. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30, further
comprising:
a first evaporator to cool a cold storage room within the inner box,
a second evaporator connected in parallel to the first evaporator to cool a freezing
room within the inner box,
a refrigerant flow passage switchover section to switch over a flow passage to one
of the first evaporator and the second evaporator, and
a compressor to discharge a refrigerant to the refrigerant flow passage switchover
section.
38. The refrigerator according to claim 37, wherein the compressor is variable revolution
type.
39. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30 further
comprising a defrosting-water pipe arranged between the outer box and the inner box,
wherein the vacuum heat insulator is arranged between the defrosting-water pipe
and the inner box.
40. The refrigerator according to any one of claims 1, 2, 4, 13, 16, 17 and 30, further
comprising a miscellaneous thing to hinder flow of the resin foam between the outer
box and the inner box,
wherein the vacuum heat insulator is arranged in locations in which the miscellaneous
thing is present.