Technical Field
[0001] The present invention relates to vibration reducing structures suitable for use in
rotary compressors including, for example, accumulators being auxiliary machines.
Background Art
[0002] As illustrated in FIG. 10, in a rotary compressor that is used in refrigerating equipment,
cylinders 102 that have internal wall surfaces and piston rotors 103 that are provided
eccentrically with respect to the centers of the cylinders 102 are provided in the
interior of a sealed container 101. The piston rotors 103 are affixed to a main shaft
104 that is provided along the central axes of the cylinders 102. The main shaft 104
is provided so as to rotate freely about its central axis via an upper bearing 105A
and a lower bearing 105B that are affixed to the cylinders 102. A rotor 106A of an
electric motor 106 is affixed to the main shaft 104. A stator 106B that is affixed
to the inner peripheral surface of the sealed container 101 is disposed around the
outer peripheral side of the rotor 106A. The main shaft 104 is driven to rotate along
with the rotor 106A by energizing the stator 106B, and the piston rotors 103 revolve
inside the cylinders 102.
[0003] The rotary compressor sucks a refrigerant into compression chambers formed between
the cylinders 102 and the piston rotors 103, and compresses the refrigerant by decreasing
the volume of the compression chambers as a result of the rotation of the piston rotors
103. The rotary compressor sucks up and compresses the refrigerant after performing
gas-liquid separation on the refrigerant using an accumulator 108.
[0004] The rotary compressor generates vibration when driving of the electric motor 106
rotates the main shaft 104. There are cases in which the vibration is transmitted
in turn to the sealed container 101 and the accumulator 108, for example, and noise
is generated.
[0005] Patent Document 1 discloses a rotary compressor in which noise and vibration generated
by excitation of an accumulator are reduced.
[0006] According to Patent Document 1, part of a connection part (22, 22A) for attaching
the accumulator to the outer peripheral surface of a sealed container (1) is bonded
to the outer peripheral surface of the sealed container (1), and a pair of leg portions
(22A) of the connection part is bonded to the outer peripheral surface of the accumulator
(2). The leg portions (22A) extend outward at an angle between 26° and 45° with respect
to the straight line connecting the center of the sealed container (1) and the center
of the accumulator (2).
[0007] Patent Document 1 states that the above configuration can prevent an increase of
noise and vibration due to resonance of the accumulator (2) by reducing a normal directional
component in the propagation of vibration from the compressor to the accumulator (2).
Citation List
Patent Document
[0008] Patent Document 1: Japanese Unexamined Patent Application Publication No.
2013-119817A (FIGS. 1 and 3)
Summary of Invention
Technical Problem
[0009] In Patent Document 1, welding is performed to affix the sealed container (1) and
the connection part (22, 22A) to each other and the accumulator (2) and the connection
part (22, 22A) to each other; however, the accumulator can also be attached by winding
a metal band around the accumulator, engaging the band, or fixing the band with a
fastener, such as a screw and a bolt.
[0010] An object of the present invention is to provide an attachment structure in which
a band is used to attach, to a vibration source such as a compressor, an auxiliary
machine of the compressor, such as an accumulator, the attachment structure being
capable of reducing the propagation of vibration from the vibration source to the
auxiliary machine.
[0011] Another object of the present invention is to provide a rotary compressor including
the attachment structure to reduce vibration of the accumulator.
Solution to Problem
[0012] In the light of the foregoing, the present invention provides an attachment structure
for attaching an auxiliary machine to a container housing a vibration source therein
by an attachment implement; the attachment implement including a holding band surrounding
and holding a periphery of any one of the container and the auxiliary machine and
including a first connection end and a second connection end, a bracket affixed to
other one of the container and the auxiliary machine and including a first connection
part connected to the first connection end of the holding band and a second connection
part connected to the second connection end of the holding band, and a buffer layer
disposed between connecting sections of the holding band and the bracket.
[0013] The attachment structure according to the present invention can prevent contact between
metals, which readily propagate vibration, in the connecting sections of the holding
band and the bracket, resulting in a reduction in the propagation of vibration from
the container to the auxiliary machine.
[0014] In the attachment structure according to the present invention, a buffer material
sheet is preferably disposed between the holding band and any one of the container
and the auxiliary machine. This configuration can reduce the propagation of vibration
from the holding band to the any one of the container and the auxiliary machine.
[0015] In the attachment structure according to the present invention, a vibration damping
structure is preferably disposed in a free region of the holding band. This configuration
can reduce the propagation of vibration via the holding band.
[0016] In the attachment structure according to the present invention, when engagement is
performed to connect the first connection end of the holding band with the first connection
part of the bracket and to connect the second connection end of the holding band with
the second connection part of the bracket, the vibration damping structure is preferably
disposed in the free region facing each of the first connection end and the second
connection end.
[0017] The region for disposing the vibration damping structure therein is provided at each
of the first connection end and the second connection end by engagement, such that
the free region has a wider area than when the free region is provided at one end,
and the vibration damping structure is disposed in a wider area. This configuration
improves a vibration damping function of the holding band.
[0018] In the attachment structure according to the present invention, when the vibration
source is an electric motor and the bracket is weld-bonded, the bracket is preferably
bonded to the auxiliary machine.
[0019] When the bracket is weld-bonded to the container housing the electric motor therein,
the bracket should be bonded in a position other than at least the position where
the electric motor is housed, to prevent thermal strain caused in the container by
the welding from inhibiting stable rotation of the electric motor. In contrast, when
the bracket is weld-bonded to the side of the auxiliary machine that does not house
the electric motor, the welding position of the bracket can be determined without
constraints of the position of the electric motor. This configuration allows the attachment
structure including the bracket to be disposed in a position where vibration is less
liable to transmit, for example, at a vibration node.
[0020] The above-described attachment structure can have the configuration in which the
vibration damping structure is disposed in the free region of the holding band and
the configuration in which the bracket is affixed to the auxiliary machine by welding
with an electric motor being the vibration source is independently compatible with
the configuration in which the buffer layer is disposed between the connecting sections
of the holding band and the bracket. The same can be applied to an electric compressor
described below.
[0021] The above-described attachment structure can be applied to an electric compressor
in which an electric motor and a compressing mechanism driven to rotate by the electric
motor are housed in a sealed container having a substantially cylindrical outside
shape and in which an accumulator is attached to the outer peripheral surface of the
sealed container with an attachment implement.
[0022] The attachment implement applied to the electric compressor includes a holding band
surrounding and holding a periphery of any one of the sealed container and the accumulator
and including a first connection end and a second connection end, a bracket affixed
to other one of the sealed container and the accumulator and including a first connection
part connected to the first connection end of the holding band and a second connection
part connected to the second connection end of the holding band, and a buffer layer
disposed between connecting sections of the holding band and the bracket.
Advantageous Effects of Invention
[0023] The attachment structure according to the present invention that includes the buffer
layer disposed between the connecting sections of the holding band and the bracket
can reduce the propagation of vibration from the container housing the vibration source
therein to the auxiliary machine.
[0024] Furthermore, the attachment structure according to the present invention that includes
the vibration damping structure disposed in the free region of the holding band can
also reduce the propagation of vibration from the container housing the vibration
source therein to the auxiliary machine.
[0025] In addition, when the vibration source is an electric motor and the bracket is affixed
by welding, the attachment structure according to the present invention that includes
the bracket affixed to the auxiliary machine can reduce the propagation of vibration
from the container housing the vibration source therein to the auxiliary machine by
disposing the attachment structure in any position that is least subject to vibration.
Brief Description of Drawings
[0026]
FIG. 1 is a cross-sectional view illustrating the configuration of a rotary compressor
according to a first embodiment of the present invention.
FIG. 2 is a front view illustrating an accumulator included in the rotary compressor
in FIG. 1.
FIG. 3 is a plan view illustrating the vicinity of the accumulator of the rotary compressor
in FIG. 1.
FIGS. 4A to 4D illustrate a bail strap used for affixing the accumulator to the rotary
compressor in FIG. 1. FIG. 4A is a side view of the bail strap, and FIG. 4B a front
view. FIG. 4C is an enlarged view illustrating an engagement connection end in FIG.
4A. FIG. 4D is an enlarged view illustrating a fastening connection end in FIG. 4A.
FIGS. 5A to 5C are views from three sides illustrating a bracket used for affixing
the accumulator to the rotary compressor in FIG. 1. FIG. 5A is a front view of the
bracket, FIG. 5B a side view, and FIG. 5C a plan view.
FIG. 6 is a plan view illustrating the vicinity of an accumulator of a rotary compressor
according to a second embodiment of the present invention.
FIG. 7A is a partially enlarged view of FIG. 6.
FIG. 7B illustrates a method for configuring a vibration damping structure.
FIG. 8 is a plan view illustrating the vicinity of an accumulator of a rotary compressor
according to a variation of the second embodiment.
FIGS. 9A and 9B illustrate the vicinity of an accumulator of a rotary compressor according
to a third embodiment of the present invention. FIG. 9A is an exploded view of components.
FIG. 9B illustrates the components assembled in predetermined positions.
FIG. 10 is a cross-sectional view illustrating a conventional rotary compressor.
Description of Embodiment(s)
[0027] The present invention will be described below in detail on the basis of embodiments
illustrated in the attached drawings.
[First Embodiment]
[0028] A rotary compressor 1 according to a first embodiment of the present invention will
now be described.
[0029] The compressor 1 uses a bail strap (holding band) 60 being a metal band to affix
an accumulator (auxiliary machine) 14 to a sealed container 11 and has a structure
to reduce the propagation of vibration from the sealed container 11 to the accumulator
14 via the bail strap 60.
[0030] A configuration of the compressor 1 will be described below, and then, effects and
benefits of the compressor 1 will be described.
[Configuration of compressor 1]
[0031] As illustrated in FIG. 1, the compressor 1 is a so-called two-cylinder type rotary
compressor in which disc-shaped cylinders 20A and 20B are provided in a two-level
upper and lower arrangement inside the cylindrical sealed container 11.
[0032] A cylindrical cylinder internal wall surface 20S is formed on the interior of each
of the cylinders 20A and 20B. Cylindrical piston rotors 21A and 21B are respectively
arranged inside the cylinders 20A and 20B, and each of the piston rotors 21A and 21B
has an outer diameter that is smaller than an inner diameter of the cylinder internal
wall surface 20S. The piston rotors 21A and 21B are respectively inserted into and
affixed to eccentric shaft portions 40A and 40B of a main shaft 23 that is arranged
along the central axis C of the sealed container 11. In this way, spaces R having
a crescent-shaped cross-section are respectively formed between the cylinder internal
wall surfaces 20S of the cylinders 20A and 20B and outer peripheral surfaces of the
piston rotors 21A and 21B.
[0033] Here, the upper side piston rotor 21A and the lower side piston rotor 21B are provided
so that a phase between them differs by 180°.
[0034] Furthermore, a disc-shaped partition plate 24 is provided between the upper and lower
cylinders 20A and 20B. Due to the partition plate 24, the space R inside the upper
side cylinder 20A and the space R of the lower side cylinder 20B do not communicate
with each other, and are partitioned into a compression chamber R1 and a compression
chamber R2.
[0035] Blades (not illustrated in the drawings) that divide each of the compression chambers
R1 and R2 into two sections are provided in the upper and lower cylinders 20A and
20B. The blades are supported in insertion grooves that extend in the radial direction
of the cylinders 20A and 20B, so that the blades can be freely advanced or retracted
in a direction to approach or move away from the piston rotors 21A and 21B.
[0036] Furthermore, a discharge hole (not illustrated in the drawings) that discharges a
refrigerant is provided in a predetermined position in each of the cylinders 20A and
20B, and a reed valve (not illustrated in the drawings) is disposed in the discharge
hole. Upon the pressure of the compressed refrigerant reaching a predetermined value,
the reed valve is pushed open and the refrigerant is discharged to the outside of
the cylinders 20A and 20B.
[0037] As illustrated in FIG. 1, the main shaft 23 is supported by an upper bearing 29A
that is affixed to the cylinder 20A and a lower bearing 29B that is affixed to the
cylinder 20B, so that the main shaft 23 can freely rotate about its central axis.
[0038] The main shaft 23 is provided with the eccentric shaft portions 40A and 40B that
are offset in a direction orthogonal to the central axis C of the main shaft 23. Each
of the eccentric shaft portions 40A and 40B has an outer diameter that is slightly
smaller than the inner diameter of each of the piston rotors 21A and 21B. In this
way, upon the main shaft 23 rotating, the eccentric shaft portions 40A and 40B revolve
around the central axis C of the main shaft 23 and the upper and lower piston rotors
21A and 21B rotate eccentrically inside the cylinders 20A and 20B. At that time, the
distal edge of each of the above-described blades advances and retracts in accordance
with the movement of the piston rotors 21A and 21B and is constantly pushed by the
piston rotors 21A and 21B.
[0039] The main shaft 23 protrudes upward from the upper bearing 29A, and a rotor 37 of
an electric motor (vibration source) 36 for rotary driving of the main shaft 23 is
integrally provided with the protruding section of the main shaft 23. A stator 38
is affixed to the inner peripheral surface of the sealed container 11 in correspondence
with the rotor 37.
[0040] The upper bearing 29A is provided with a discharge hole (not illustrated in the drawings)
that communicates with the discharge hole formed in the cylinder 20A, and the refrigerant
that has passed through the cylinder 20A passes through the discharge hole in the
upper bearing 29A and is discharged to the interior of a muffler 45A that will be
described below. Similarly, the lower bearing 29B is provided with a discharge hole
(not illustrated in the drawings) that communicates with the discharge hole formed
in the cylinder 20B, and the refrigerant that has passed through the cylinder 20B
passes through the discharge hole in the lower bearing 29B and is discharged to the
interior of a muffler 45B that will be described below.
[0041] As illustrated in FIG. 1, in the compressor 1, the muffler 45A is mounted on the
upper bearing 29A, and the muffler 45B is mounted on the lower bearing 29B. Upon the
refrigerant that has passed through the upper bearing 29A and the lower bearing 29B
flowing into the interior of the muffler 45A and the muffler 45B, respectively, a
pulsating component is removed. The refrigerant from which the pulsating component
has been removed passes through a discharge channel formed in the muffler 45A and
the muffler 45B, and flows toward the upper part of the sealed container 11.
[0042] Openings 12A and 12B are formed in the sides of the sealed container 11, in positions
facing outer peripheral surfaces of the cylinders 20A and 20B. Intake ports 30A and
30B that communicate as far as predetermined positions of the cylinder internal wall
surfaces 20S are formed in the cylinders 20A and 20B, in positions facing the openings
12A and 12B.
[0043] As illustrated in FIG. 1, in the compressor 1, the accumulator 14 that performs gas-liquid
separation on the refrigerant before the refrigerant is supplied to the compressor
1 is affixed to the sealed container 11 via an attachment structure 50.
[0044] Intake pipes 16A and 16B are provided in the accumulator 14, for causing the refrigerant
inside the accumulator 14 to be sucked into the compressor 1. The tip portions of
the intake pipes 16A and 16B are connected to the intake ports 30A and 30B via the
openings 12A and 12B.
[0045] The compressor 1 takes up the refrigerant into the accumulator 14 from an intake
tube 14a of the accumulator 14, performs gas-liquid separation on the refrigerant
inside the accumulator 14, and supplies the resulting gas phase from the intake pipes
16A and 16B to the compression chambers R1 and R2, which are internal spaces of the
cylinders 20A and 20B, via the intake ports 30A and 30B of the cylinders 20A and 20B.
[0046] Then, the volume of the compression chambers R1 and R2 is gradually decreased by
the rotation of the piston rotors 21A and 21B inside the cylinder 20A and 20B, and
the refrigerant is compressed. The compressed refrigerant passes through the upper
bearing 29A and the muffler 45A on the cylinder 20A side and passes through the lower
bearing 29B and the muffler 45B on the cylinder 20B side, and is discharged into the
interior of the sealed container 11 (the outside of the muffler 45A and the muffler
45B). After passing through the electric motor 36, the refrigerant is evacuated to
a pipe that forms a refrigerant cycle, via a discharge tube 42 that is provided in
an upper portion.
[0047] The accumulator 14 is attached to the sealed container 11 of the compressor 1 via
the intake pipes 16A and 16B, and the accumulator 14 and the sealed container 11 are
also affixed to each other through the attachment structure 50.
[0048] As illustrated in FIG. 1, the attachment structure 50 includes the bail strap 60
wound around the accumulator 14, a bracket 70 affixed to the sealed container 11,
and a buffer material 75 made of a sheet rubber and disposed between the bail strap
60 and the sealed container 11.
[0049] As illustrated in FIGS. 3, 4A, 4B, 4C, and 4D, the bail strap 60 includes an engagement
connection end (first connection end) 62 formed by bending one end into a U-shape,
a fastening connection end (second connection end) 63 formed by bending the other
end into an L-shape, and a fastening portion 61 extending between the engagement connection
end 62 and the fastening connection end 63. The engagement connection end 62 is inserted
into an engagement groove 723 (FIGS. 5A and 5B) provided in the bracket 70 to affix
the one end of the bail strap 60 to the bracket 70. Furthermore, the fastening connection
end 63 is fastened to the bracket 70 with a bolt B to affix the other end of the bail
strap 60 to the bracket 70. A bolt hole 64 (FIG. 4B) for passing the bolt B therethrough
is formed in the fastening connection end 63. When the engagement connection end 62
and the fastening connection end 63 are affixed to the bracket 70, the securing portion
61 is wound around the accumulator 14 and secures the accumulator 14.
[0050] The bail strap 60 is manufactured through sheet-metal processing in which a metal
plate is subjected to punching and bending to have a shape illustrated in FIGS. 3,
4A, 4B, 4C, and 4D. The bracket 70 is manufactured in a similar manner.
[0051] The bail strap 60 is provided with a buffer layer 62S and a buffer layer 63S at
the engagement connection end 62 and the fastening connection end 63, respectively.
The buffer layer 62S and the buffer layer 63S may be formed by pasting a buffer material
sheet composed of a buffer material made of, for example, natural or synthetic rubber,
or synthetic resin. Alternatively, the layers may be formed by applying an adhesive
gel and then curing the gel.
[0052] The buffer layer 62S of the engagement connection end 62 is disposed on an inner
peripheral surface 60
IS of the bail strap 60. When the engagement connection end 62 is inserted into the
engagement groove 723 of the bracket 70 and engaged with the engagement connection
part 72, the buffer layer 62S is positioned between the engagement connection end
62 and the bracket 70 to prevent contact between the metals, which will be described
in detail later.
[0053] The buffer layer 63S of the fastening connection end 63 is disposed on the inner
peripheral surface 60
IS of the bail strap 60. When the fastening connection end 63 is fastened to the bracket
70 with the bolt B, the buffer layer 63S is positioned between the fastening connection
end 63 and the bracket 70 to prevent contact between the metals, which will be described
in detail later.
[0054] As illustrated in FIGS. 3, 5A, 5B, and 5C, the bracket 70 includes a weld-bonded
portion 71 to be affixed to the sealed container 11, and the engagement connection
part (first connection part) 72 and a fastening connection part (second connection
part) 73 respectively provided at tip ends of flanges 714 and 714 of the weld-bonded
portion 71 used for affixing the bail strap 60.
[0055] The bracket 70 is arranged in a predetermined position and then bonded and affixed
to the sealed container 11 by welding the weld-bonded portion 71.
[0056] The weld-bonded portion 71 has a similar cross section to that of a steel channel
and includes a web 711 and the flanges 714 and 714 rising perpendicularly from both
edges of the web 711. The web 711 is curved so as to have a curvature equivalent to
that of the outer peripheral surface of the sealed container 11 and is provided with
a pair of positioning protrusions 713 and 713 that are disposed on a bonded surface
712 to be bonded to the sealed container 11 with a space therebetween and are used
for positioning with respect to the sealed container 11. The positioning protrusions
713 and 713 are fitted into positioning grooves (not illustrated in the drawings)
formed in predetermined positions of the outer peripheral surface of the sealed container
11 to position the bracket 70.
[0057] The engagement connection part 72 and the fastening connection part 73 are each formed
to have a substantially L-shaped cross section and respectively correspond to the
engagement connection end 62 and the fastening connection end 63 of the bail strap
60.
[0058] The engagement connection part 72 includes a first supporting portion 721 and an
engagement portion 722 formed by bending the tip end of the first supporting portion
721. The first supporting portion 721 comes into contact with the accumulator 14 and
supports the accumulator 14. The surface in contact with the accumulator 14 has a
curvature equivalent to that of the outer peripheral surface of the accumulator 14.
Similarly, a second supporting portion 731 of the fastening connection part 73 comes
into contact with the accumulator 14 and supports the accumulator 14. The surface
in contact with the accumulator 14 has a curvature equivalent to that of the outer
peripheral surface of the accumulator 14. The engagement groove 723 for engagement
with the engagement connection end 62 of the bail strap 60 is formed in the engagement
portion 722.
[0059] The fastening connection part 73 includes the second supporting portion 731 and a
fastening portion 732 formed by bending the tip end of the second supporting portion
731. The flat fastening portion 732 supports the fastening connection end 63, laminated
thereon, of the bail strap 60 and fastens and affixes the fastening connection end
63 by fastening the bolt B. A screw hole 733 through which the bolt B passes and that
has a female thread formed thereon for engagement with the male thread of the bolt
B is formed in the fastening portion 732.
[0060] The flanges 714, the first supporting portion 721, and the second supporting portion
731 of the bracket 70 are elastic, and their elastic deformation converts vibration
energy into thermal energy, resulting in a reduction in the propagation of vibration.
[0061] As illustrated in FIGS. 1 and 2, the buffer material 75 is composed of a rubber sheet
and wound around the accumulator 14. The buffer material 75 is disposed between the
accumulator 14 and the bail strap 60 to reduce the propagation of vibration from the
bail strap 60 to the accumulator 14.
[0062] The buffer material 75 surrounds the outer peripheral surface of the accumulator
14 by almost one round and is held between the accumulator 14 and the bail strap 60
by the bail strap 60 securing the buffer material 75 on its periphery.
[0063] The accumulator 14 is attached to the sealed container 11 with the attachment structure
50 including the above-described bail strap 60, bracket 70, and buffer material 75.
In specific, the outer peripheral surface of the accumulator 14 is brought into contact
with the first supporting portion 721 and the second supporting portion 731 of the
bracket 70 weld-bonded in a predetermined position of the sealed container 11 as illustrated
in FIGS. 1 to 3. In this state, the engagement connection end 62 of the bail strap
60 is fitted into the engagement groove 723 formed in the engagement portion 722 of
the engagement connection part 72 of the bracket 70 to engage the engagement connection
end 62 with the engagement connection part 72. The fastening connection end 63 of
the bail strap 60 is then overlapped on the fastening portion 732 of the fastening
connection part 73 of the bracket 70. Consequently, the securing portion 61 of the
bail strap 60 covers the periphery of the accumulator 14. Then, the bolt B with its
screw portion having passed through the bolt hole 64 is screwed into the screw hole
733 of the fastening portion 732. The bolt B is screwed until its head portion reaches
the fastening portion 732 and required securing force is yielded. This completes the
attachment of the accumulator 14.
[0064] An effect of the compressor 1 will now be described. The effect relates to a reduction
in the propagation of vibration generated by driving of the electric motor 36 in the
main body of the compressor 1 including the sealed container 11, to the accumulator
14.
[0065] As illustrated in FIGS. 3, 4A, 4B, 4C, and 4D, in the present embodiment, the buffer
layer 62S is provided at the engagement connection end 62 of the bail strap 60 and
positioned between the engagement connection end 62 and the engagement portion 722
of the bracket 70. Furthermore, the buffer layer 63S is provided at the fastening
connection end 63 of the bail strap 60 and positioned between the fastening connection
end 63 and the fastening portion 732 of the bracket 70. The buffer layers 62S and
63S positioned between the bail strap 60 and the bracket 70 decrease the transmissibility
of vibration generated in the sealed container 11, from the bracket 70 to the bail
strap 60, resulting in a reduction in vibration of the accumulator 14.
[Second Embodiment]
[0066] Next, a compressor 2 according to a second embodiment of the present invention will
be described with reference to FIGS. 6, 7A, and 7B.
[0067] The compressor 2 has the same basic configuration as the compressor 1, and the same
components in FIGS. 6 to 8 have the same reference characters used for the compressor
1. Features, differing from the compressor 1, of the compressor 2 will be mainly described
below.
[0068] As illustrated in FIGS. 6, 7A, and 7B, the compressor 2 includes a vibration damping
structure 65 in the bail strap 60. The vibration damping structure 65 is disposed
in a free region F that is on the side provided with the engagement connection end
62 of the bail strap 60 and does not come into contact with the accumulator 14 and
the bracket 70 so as not to have direct mechanical constraints. Here, it is assumed
that the vibration damping structure 65 extends in the entire free region F in the
width direction W (See FIG. 4B) of the bail strap 60. Alternatively, the vibration
damping structure 65 may extend only in a partial region in the width direction W.
[0069] The vibration damping structure 65 has a similar structure to that of a laminated
damping steel sheet.
[0070] A laminated damping steel sheet has a structure in which a viscoelastic resin layer
having a thickness of approximately several tens µm is disposed between two steel
sheets, and shear deformation of the viscoelastic resin layer due to bending vibration
converts vibration energy into thermal energy to yield vibration damping effects.
[0071] The vibration damping structure 65 is composed of a viscoelastic resin layer 67 and
a steel sheet 68 with the bail strap 60 functioning as one of the two steel sheets.
In other words, the vibration damping structure 65 has a laminated structure in which
the viscoelastic resin layer 67 is disposed between the bail strap 60 and the steel
sheet 68.
[0072] As illustrated in FIG. 7B, the vibration damping structure 65 is obtained by laminating
the viscoelastic resin layer 67 and the steel sheet 68 to prepare a vibration damping
structure preparatory body 66 and pasting the viscoelastic resin layer 67 side on
the bail strap 60.
[0073] Here, the vibration damping structure 65 disposed on the outer peripheral surface
60
os of the bail strap 60 is exemplified. Alternatively, the vibration damping structure
65 may be disposed on the inner peripheral surface 60
IS or on both of the outer peripheral surface 60
OS and the inner peripheral surface 60
IS.
[0074] In the present embodiment, the vibration damping structure 65 is disposed in the
free region F. Consequently, even when vibration is transmitted from the bracket 70,
shear deformation of the viscoelastic resin layer 67 of the vibration damping structure
65 damps vibration in the free region F. The propagation of vibration to the accumulator
14 can thus be reduced.
[0075] In the present embodiment, the vibration damping structure 65 disposed only in the
free region F is exemplified. Alternatively, the vibration damping structure 65 may
be disposed in a region other than the free region F. However, since shear deformation
of the viscoelastic resin layer 67 provides the vibration damping effects of the vibration
damping structure 65, the vibration damping structure 65 is preferably disposed in
a section selected for yielding the effects and benefits. Furthermore, the vibration
damping structure 65 may be disposed not only on the bail strap 60 but also on the
bracket 70 side.
[0076] The vibration damping effects of the vibration damping structure 65 can be more effectively
yielded by expanding the free region F and disposing the vibration damping structure
65 in the free region F. FIG. 8 illustrates an example in which the vibration damping
structure 65 is disposed on the basis of this viewpoint.
[0077] In a compressor 1 in FIG. 8, both ends of the bail strap 60 and the bracket 70 are
affixed by engagement, such that the free region F can be expanded twice as large
as the example in FIG. 6. Consequently, the vibration damping effects can be doubled
by disposing the vibration damping structure 65 in each of the free regions F.
[0078] The second embodiment illustrated in FIGS. 6 to 8 exemplifies a configuration without
the buffer layers 62S and 63S in the first embodiment; however, the buffer layers
62S and 63S in the first embodiment may be applied to the second embodiment.
[Third Embodiment]
[0079] Next, a compressor 3 according to a third embodiment of the present invention will
be described with reference to FIGS. 9A and 9B.
[0080] The compressor 3 has the same basic configuration as the compressors 1 and 2, and
the same components in FIGS. 9A and 9B have the same reference characters used for
the compressors 1 and 2. Features, differing from the compressors 1 and 2, of the
compressor 3 will be mainly described below.
[0081] As illustrated in FIGS. 9A and 9B, the compressor 3 has a structure in which a bracket
70 is bonded to the accumulator 14 and a bail strap 60 is wound around the sealed
container 11.
[0082] The bail strap 60 and the bracket 70 follow the configuration of the second embodiment.
The bail strap 60 includes two engagement connection ends 62 on both ends thereof,
and the bracket 70 includes two engagement connection parts 72 on both ends thereof.
[0083] In the bracket 70, a weld-bonded portion 71 is affixed to the accumulator 14 by welding.
In the bail strap 60, a securing portion 61 (not illustrated in the drawings) is wound
around the sealed container 11, and the engagement connection ends 62 and 62 are respectively
engaged with the engagement connection parts 72 and 72 of the bracket 70 to affix
the accumulator 14 to the sealed container 11.
[0084] The compressor 3 according to the third embodiment does not have constraints on the
height position of attaching the bracket 70 by welding, which will be described below,
and thus achieves such an effect that the attachment structure 50 can be disposed
in a position selected so that vibration from the sealed container 11 is the less
liable to propagate to the accumulator 14.
[0085] As illustrated in FIG. 1, the sealed container 11 houses the electric motor 36 therein
and also functions as the case of the electric motor 36. The sealed container 11 is
thus required to have a high roundness especially at a section housing the electric
motor 36 to ensure stable rotation of the rotor 37. Since welding of the bracket 70
to the sealed container 11 inevitably causes thermal strain in the sealed container
11, the bracket 70 is welded in a region other than a region A housing the electric
motor 36 to prevent influences of the thermal strain on the region A in the first
and second embodiments in which the bracket 70 is welded to the sealed container 11.
[0086] Welding of the bracket 70 to the sealed container 11 has constraints on the height
position of welding as described above. Unfortunately, the constraints on the welding
position is undesirable in consideration of the propagation of vibration. That is,
the stator 38 of the housed electric motor 36 is fitted inside the sealed container
11, such that the region A of the sealed container 11 has high rigidity and readily
reduces the amplitude of vibration. Therefore, when the bracket 70 is affixed in the
region A, vibration from the sealed container 11 is less liable to propagate to the
bracket 70.
[0087] For this reason, the bracket 70 is welded to the accumulator 14, which is not adversely
affected by thermal strain by welding, in the present embodiment. This configuration
enables the bracket 70 to be affixed by welding in a position selected in a wide region
B including the region A illustrated in FIG. 1 to readily reduce the amplitude of
vibration. Thermal strain by welding is not generated in the sealed container 11,
and stable rotation of the electric motor 36 is thus ensured.
[0088] Furthermore, the compressor 3 according to the third embodiment also achieves such
an effect that the magnitude of exciting force input to the bracket 70 is reduced
by winding the bail strap 60 around the sealed container 11, which will be described
below.
[0089] It is understood that vibration of the sealed container 11 generates exciting force
F (F
1, F
2, F
3, and F
4) to the outside approximately in the positions indicated in FIG. 9B. When the exciting
force F
1, F
2, F
3, and F
4 overlaps and generates greater exciting force, vibration propagated via the bracket
70 to the accumulator 14 increases. It is thus required to prevent the exciting force
F
1, F
2, F
3, and F
4 from overlapping to reduce vibration of the accumulator 14. The present embodiment
has the configuration in which the bracket 70 is affixed to the accumulator 14 by
welding and the bail strap 60 is wound around the sealed container 11 having a larger
diameter than that of the accumulator 14, and a distance between F
1 and F
2 and a distance between F
3 and F
4 can thus be increased, resulting in a reduction of overlapping exciting force.
[0090] In the present embodiment, the sealed container 11, around which the bail strap 60
is wound, has a larger external diameter than that of the accumulator 14. The distance
D between the positions in which the exciting force F
1 and the exciting force F
2 are generated and the distance D between the positions in which the exciting force
F
3 and the exciting force F
4 are generated can thus be increased in comparison with the case in which the bail
strap 60 is wound around the accumulator 14. The increase in the distances between
the exciting force F (F
1, F
2, F
3, and F
4) to disperse the force enables input of the exciting force to the bracket 70 with
the phase of the exciting force differing from each other, resulting in a prevention
of overlapping exciting force.
[0091] The third embodiment illustrated in FIG. 9 exemplifies a configuration without the
buffer layers 62S and 63S in the first embodiment and the vibration damping structure
65 in the second embodiment; however, the buffer layers 62S and 63S in the first embodiment
and the vibration damping structure 65 in the second embodiment may be applied to
the third embodiment.
[0092] The present invention has been described with reference to the first, second, and
third embodiments. However, as long as there is no departure from the spirit and scope
of the present invention, configurations described in the above embodiments can be
selected as desired, or can be changed to other configurations as necessary.
[0093] The above embodiments exemplify the electric motor of the rotary compressor being
a vibration source and the accumulator being an auxiliary machine associated with
the vibration source; however, these should not be construed to limit the present
invention. The present invention can be widely applied to a combination of a vibration
source other than a rotary compressor and an auxiliary machine other than an accumulator.
[0094] Furthermore, if the present invention is applied to a rotary compressor, its specific
configuration should not be limited to those described in the embodiments. The present
invention can be widely applied to a rotary compressor including a rotary compressing
mechanism, a sealed container, and an accumulator.
Reference Signs List
[0095]
- 1, 2, 3
- Compressor
- 11
- Sealed container
- 12A
- Opening
- 12B
- Opening
- 14
- Accumulator (Auxiliary machine)
- 14a
- Intake tube
- 16A
- Intake pipe
- 16B
- Intake pipe
- 20A
- Cylinder
- 20B
- Cylinder
- 20S
- Cylinder internal wall surface
- 21A
- Piston rotor
- 21B
- Piston rotor
- 23
- Main shaft
- 24
- Partition plate
- 29A
- Upper bearing
- 29B
- Lower bearing
- 30A
- Intake port
- 30B
- Intake port
- 36
- Electric motor (Vibration source)
- 37
- Rotor
- 38
- Stator
- 40A
- Eccentric shaft portion
- 40B
- Eccentric shaft portion
- 42
- Discharge tube
- 45A
- Muffler
- 45B
- Muffler
- 50
- Attachment structure
- 60
- Bail strap (Holding band)
- 60IS
- Inner peripheral surface
- 60OS
- Outer peripheral surface
- 61
- Securing portion
- 62
- Engagement connection end (First connection end)
- 62S
- Buffer layer
- 63
- Fastening connection end (Second connection end)
- 63S
- Buffer layer
- 64
- Bolt hole
- 65
- Vibration damping structure
- 66
- Vibration damping structure preparatory body
- 67
- Viscoelastic resin layer
- 68
- Steel sheet
- 70
- Bracket
- 71
- Weld-bonded portion
- 72
- Engagement connection part (First connection part)
- 73
- Fastening connection part (Second connection part)
- 75
- Buffer material
- 711
- Web
- 712
- Bonded surface
- 713
- Positioning protrusion
- 714
- Flange
- 721
- First supporting portion
- 722
- Engagement portion
- 723
- Engagement groove
- 731
- Second supporting portion
- 732
- Fastening portion
- 733
- Screw hole
- B
- Bolt
- C
- Central axis
- R
- Space
- R1
- Compression chamber
- R2
- Compression chamber