FIELD OF THE INVENTION
[0001] This invention is broadly concerned with inking rollers in a printing machine or
several rollers in a machine for processing plastic films and intended particularly
to be used to a heating or cooling roller (referred to as a thermal roller in the
following description ) being in control of its surface temper ature by being heated
or cooled.
DESCRIPTION OF THE PRIOR ART
[0002] Rollers rotating in contact with others are generally employed in several machinery.
Taking for an instance, there are arranged several inking rollers between an ink reservoir
and a plate cylinder in the printing machine to feed ink to plates which are attached
to the plate cylinder by transmitting ink sequentially from one roller to the other
contiguous roller. These rollers are apt to go up the temperature of ink on the surface
thereof due to a rolling friction heat generated by rotate in contact with others.
But, according to specifications of ink, several conditions such as an admirable temperature
and range of temperature in use of ink are prescribed. The preferable temperature
of ink in offset press is generally recommended to be about 28 degrees. It is then
noted that the surface temperature of the inking roller being out of the mentioned
conditions for ink becomes a main cause to spoil quality of printed papers. It is
also observed in a case of low room temperature in a cold district that the printing
machine should be idled until the temperature of ink reaches to the admirable one
for the start of daily work, which causes a drop in productivity.
[0003] Reflecting such prior art in this field of invention, some of technology to cool
and heat the roller have been proposed so as to keep the surface temperature of roller
preferable level. Some of known technology to cool the roller are as follows; a water-cooled
method wherein a water such as ground water is circulated in the roller, a freeze-cycle
method wherein a heat exchange is effected by a cooling water or refrigerant, and
a heat-pipe method. An official gazette issued January 11th in 1988 under the Japanese
Patent Laid-open No. SHO 63-5944, as an example of conventional technology, described
a cylinder-cooling device applying the freeze-cycle method. As another reference,
the Japanese Patent Laid-open No. HEI 3-21453 issued on January 30th in 1991 proposes
a method of controlling the temperature of ink on the plate attached to a plate cylinder,
wherein a fluid medium is circulated in the plate cylinder to control the temperature
of ink by regulating the fluid medium.
[0004] Accordingly, it will be observed that a thermal roller employing a fluid medium should
be closed up tightly and produced precisely. Moreover, such a conventional device
essentially needs a water or heated water circulatory device and a refrigerator, which
is undesirable in view of the space. Furthermore, there may be a complicated control
to effect a desirable operation behind the conventional device and a troublesome maintenance.
SUMMARY OF THE INVENTION
[0005] It is an object of the present invention to provide a roller which is enough to have
a little components to be heated or cooled upon a necessity, and which is preferable
in view of maintenance.
[0006] According to this invention, heat pipe are coupled into a roller body from its one
end so as to extend partly, so that a components to heat or cool the roller can be
minimized. Furthermore, since a thermal transmissible member can be filled in to,
so that maintenance become easy.
[0007] According to one preferable embodiment of this invention, a roller to be heated or
cooled has a solid roller body having a hole provided from at least one end along
a central axis thereof and one or more heat pipes coupled into one or more holes of
the roller body to partly extend therefrom.
[0008] When heating the roller, the heat pipe extended from the roller body is first heated
and the applied heat is transmitted to the roller body. While, cooling the roller,
unnecessary heat is released from the heat pipe. If fins are provided on the heat
pipe extended from the roller body, thermal transmission will be accelerated to facilitate
preferable thermal control.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 is a fragmentary sectional view of a thermal roller using a heat pipe according
to this invention.
[0010] Figure 2 is an enlarged front view of a modification of a fin-type radiation device.
[0011] Figure 3 is a side view from the A-A line in Figure 2.
[0012] Figure 4 is an explanatory view of a device for compulsorily cool the radiation device
of the heat pipe by air.
[0013] Figure 5 is a sectional view of a thermal roller using two independent heat pipes.
[0014] Figure 6 is a sectional view of a thermal hollow roller using a plurality of heat
pipes.
[0015] Figure 7 is a sectional view taken along the B-B line in Figure 6.
[0016] Figure 8 is a sectional view from the C-C line in Figure 6.
[0017] Figure 9 is a sectional view of a thermal hollow roller using heat pipes in an inner
sleeve.
[0018] Figure 10 is a sectional view taken along the D-D line in Figure 9.
[0019] Figure 11 is a sectional view taken along the D-D line in Figure 9 to show another
arrangement of heat pipes.
[0020] Figure 12 is a sectional view of another modification of roller composition.
[0021] Figure 13 is a sectional view taken along the E-E line in Figure 12.
[0022] Figure 14 is a sectional view showing a modification of roller composition and an
embodiment of a heat/cool device employing an electrical thermal element.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0023] The preferred embodiments of the present invention will now be described with reference
to the drawings. Figure 1 shows the overall composition of a thermal roller(referred
to as a roller in the following description) having a heat pipe which is coupled thereto
along the axis thereof. The roller is arranged to have a radiation section or a heat-inlet
section therein to go up its temperature having heat and to give off heat from the
roller body to go down its temperature. As can be understood, a fundamental composition
of the roller in this embodiment is almost the same, so that only a roller which should
be cooled will be explained in detail.
[0024] A roller 1 comprises a roller body 3 of which a shaft 4 is rotatably supported in
a bearing 5 fixed to a side frame 2 of a whole device. The roller body 3 is provided
with a deep hole axially aligned with its axis therein which receives an heat-inlet
section 11 of a heat pipe 10. A radiation section 12 of the heat pipe 10 is extended
from one end of the roller 1 and projected over the side frame 2. At the other end
of the roller 1, there is provided a drive gear 20 to rotate the roller. The radiation
section 12 of the heat pipe 10 has thereon a radiation device 13 including plural
fins.
[0025] The heat pipe 10 contains a working fluid such as water or fleon after decompressing
the inside pressure. The contained working fluid is once vaporized at the heat-inlet
section 11 by heat and then moved to the radiation section 12 to be condensed. The
thus condensed working fluid is returned to the heat-inlet section 11 so that a heat
transfer from the heat-inlet section 11 to the radiation section 12 is effected to
thereby cool the roller.
[0026] The radiation device 13 includes a plurality of plate-like fins at certain intervals.
The fin used in the device 13 may be in a shape of a circle, a four-sided figure or
a spiral. The fin 13a shown in Figure 1 is formed into a round shape, its surfaces
being parallel to the rotating direction of the roller and each of the fins being
disposed along the axis of the heat pipe 10 at spaced intervals so as to form the
radiation device 13.
[0027] Referring now to Figure 2, a modification of fin is shown. The radiation device 13
is defined by fins 13b each having a four-sided figure shape. The plural fins 13b
are radially secured to the heat pipe 10.
[0028] It will be apparent that a spiral fin (not shown) is also available to be used as
the radiation device 13.
[0029] An effectiveness of radiation will be improved using such fin composition for the
radiation device 13 since the fins rotate together with the roller.
[0030] Figure 4 shows an modification to compulsorily cool by air. The radiation section
12 and the radiation device 13 of the heat pipe 10 are accommodated in a case 14,
all together. The case has an inlet 15 for fresh air to cool and an outlet 16 for
exhaust from the radiation device where the heat exchange can be carried out. The
outlet 16 can be connected with a blower 18 to exhaust the used air via a piping 17.
The evaporated working fluid in the radiation section 12 of the heat pipe can be condensed
and liquefied by radiating the latent heat of condensation from the radiation device
13 to the inside space of the case 14. It will be apparent that the thus radiated
heat in the case 14 is exhausted by the blower 18.
[0031] An effectiveness of absorption for the latent heat of condensation will be improved
since the blower 18 compulsorily exhausting useless air can expedite the condensation
of the evaporated working fluid. Accordingly, the effectiveness of cooling in the
roller can be improved.
[0032] Figure 5 shows another embodiment of the roller according to this invention. The
shown composition is characterized to have therein two of independent heat pipes 101
and 102 which are adapted to be received in a through hole by being inserted from
the ends of the roller, respectively.
[0033] Radiation sections 111, 112 of the heat pipes projected from the ends of the roller
are provided with the radiation device 13 including plural fins.
[0034] It can be expected that the vaporized working fluid will be cooled faster as a circulation
distance, from one portion where the working fluid is cooled to the other portion
where the working fluid is heated, is shortened. When using a rather long roller having
the mentioned two independent heat pipes, the roller can be cooled separately to thereby
suppress the temperature gradient on the roller surface compared with a roller using
a single heat pipe.
[0035] Referring to Figure 6, another embodiment of a roller according to this invention
is shown. The shown roller 30 is characterized to have a hollow portion in its body
and receive plural heat pipes inside.
[0036] The roller 30 is defined by a roller body 31 having a cylindrical shape and roller
shafts 33 fixed to flanges 32 attached to openings of the roller body 31. The roller
shaft 33 is held in a bearing secured to the frame 2 of the whole device so as to
rotate. The roller body 31 are arranged to include , as in shown Figure 7, a plurality
of insertion holes 34 lengthwisely for heat pipes on a common circle. The insertion
hole 34 is adapted to received the heat pipe 10 therein. The projected portions of
the respective heat pipes 10 are connected all together with a common radiation device
35.
[0037] The radiation device 35 includes, as shown in Figure 8, a plurality of disk-like
fins 35a, each fin having at its center portion a hole 35b for the roller shaft 33
and also at its periphery portion holes corresponding plural heat pipes 10.
[0038] It will be apparent that the radiation device 35 in this embodiment is disposed at
one side of the roller, but the same device may be provided at the other side as shown
in Figure 5, wherein the heat pipe 10 were separately and lengthwisely received in
the roller body 30, whereby an equivalent operation and effect in Figure 5 may be
achieved.
[0039] Figure 9 shows still another embodiment of the roller according to this invention.
The shown roller is characterized to have an arrangement that a roller body 41 is
coupled to an inner sleeve 42 and the inner sleeve 42 is provided to receive plural
heat pipes 10 therein. The shown components fulfilling the same function as the mentioned
embodiment in Figure 8 are denoted by the same numerals and the corresponding explanation
will be obviated.
[0040] The roller 40 is assembled so that the cylindrical roller body 41 is coupled to the
inner sleeve 42 by means of a press fitting or a shrinkage fitting and the heat pipes
10 are inserted into through holes 43 of the inner sleeve 42.
[0041] It will be noted that the heat pipes 10 are disposed on a common circle in the inner
sleeve 42, but when the inner sleeve 42 has a certain thickness, another arrangement
of the heat pipes 10 that are on two different circles and in a radial pattern not
to radially aligned each other is also available as shown in Figure 11. That is, there
are an outer series of the heat pipes 10a near the roller surface and an inner series
of the heat pipes 10b, each of pipes 10b being oriented intermediate one heat pipe
10a and another. When employing such arrangement of heat pipes, the temperature gradient
in a circumferential direction on the roller surface can be suppressed.
[0042] Figure 12 also presents another embodiment of the roller according to this invention.
In this embodiment, the inner surface of the roller body 41 does not directly contact
with the outer surface of the inner sleeve 42 but there is provided a layer of a high-thermal
transmissible cement 44 between members 41 and 42 to advance an efficiency of thermal
transmission between the two members. This arrangement does not require a high precision
of processing the inner surface of the roller body and the outer surface of the inner
sleeve, which facilitates an easy machine processing.
[0043] Figure 14 shows still another embodiment of the roller in this invention. This embodiment
is characterized to include a heat-inlet section of the heat pipe in the hollow roller
body.
[0044] The roller 50 is defined by a roller body 51 being of a hollow cylinder opened both
ends and roller shafts 52a fixed to flanges 52 attached to openings of the roller
body 51. The roller shaft 52a is held in a bearing 5 secured to the frame 2 of the
whole device so as to rotate.
[0045] A sleeve 53 is provided in the roller body 51 to held therein a heat pipe 10 axially
aligned with the roller shaft 52a. One end of the sleeve 53 is secured to one flange
52 and the other is kept in the other flange 52 and the roller shaft 52a to thereby
rotate along with the roller body. The sleeve 53 is provided with a thermal absorption
device 54 defined by plural fins in the roller body. A portion of the heat pipe 10
extended from the sleeve 53 has the radiation device 13 defined by fins.
[0046] The radiation device 13 is covered with a case 55 which houses a heat/cool device
60 employing electrical thermal elements. The heat/cool device 60 comprises a thermal
electrode 61a, an electrical thermal element 61 having a heat release electrode 61b,
a heat release fin 62 attached to the heat release electrode 61b of the electrical
thermal element 61, a fan case 63 to cover the heat release fin 62, and an air fan
64.
[0047] Attaching the fan case 63 to the case 55, the thermal electrode 61a is oriented in
the case 55. A reversible operation of the electrical thermal element 61 may facilitate
an absorption of heat radiated from the heat pipe 10 or an application of heat thereto.
[0048] When cooling the roller, the heat/cool device 60 is operated as to be a cooling device
in order to take out unnecessary heat from the radiation section of the heat pipe
(in the case 55). In this case, the air fan 64 draws fresh air via an inlet opening
65 of the fan case and the unnecessary heat is removed from the heat release fin 62.
The vaporized working fluid in the radiation section of the heat pipe can be appropriately
liquefied, so that the cooling effectiveness of the roller is accelerated to return
to the heat-inlet section.
[0049] In the mentioned embodiment, the roller is heated or cooled by controlling the electrical
thermal element. It will be apparent that the heat/cool device employing the electrical
thermal element is not only utilized in the roller shown in Figure 14, but also in
other rollers already explained.
[0050] It will be mentioned, however, that when heating the roller, a portion of the heat
pipe extended from the roller body will be used as the heat-inlet section and a portion
of the heat pipe in the roller body will be used as the radiation portion. In this
composition, the heat-inlet section will be heated. If the roller is provided with
the heat/cool device using the electrical thermal element, the roller can be heated
easily by reversing the electrical current to the electrical thermal element.
1. A roller to be heated or cooled, comprising at least one heat pipe (10) which is arranged
inside the roller body (3) and which has a heat exchange relationship with said roller
body, wherein at least one end of said heat pipe (10) projects from said roller and
is coupled to heating or cooling means (13).
2. A roller to be heated or cooled according to claim 1, comprising a solid roller body
(3) having one or more holes provided from at least one end along a central axis thereof;
and one or more heat pipes (10; 101, 102) coupled into the holes of said roller body
(3) to partly extend therefrom, so that said roller is heated or cooled by a heat
exchange of said heat pipes (10; 101, 102).
3. A roller to be heated or cooled according to claim 1, comprising:
a hollow roller body (31) having a plurality of through holes (34) each parallel to
a line segment forming a side of said roller body (31); and heat pipes (10) coupled
into the through holes (34) of said roller body (31) to partly extend therefrom, so
that said roller is heated or cooled by a heat exchange of said heat pipes (10).
4. A roller to be heated or cooled according to claim 1, comprising:
a hollow roller body (41);
an inner member (42) entirely coupled into said hollow roller body (41) and including
a plurality of through holes (43); and
heat pipes (10) coupled into the through holes (43) of said inner member (42) to partly
extend therefrom, so that said roller is heated or cooled by a heat exchange of said
heat pipes.
5. A roller to be heated or cooled according to claim 1, comprising:
a hollow roller body (41);
an inner member (42) entirely loosely coupled into said hollow roller body (41) and
including a plurality of through holes (43);
heat pipes (10) coupled into the through holes (43) of said inner member to partly
extend therefrom; and
a layer (44) of a high-thermal transmissible cement between said hollow roller body
(41) and said inner member (42) to advance an efficiency of thermal transmission therebetween,
so that said roller is heated or cooled by a heat exchange of said heat pipes.
6. A roller to be heated or cooled according to claim 1, comprising:
a roller body (51) having therein a sealed-up space;
a sleeve (53) having fins (54) lengthwisely in the space of said roller body (51);
and
a heat pipe coupled into said sleeve (53) to partly extend therefrom, so that said
roller is heated or cooled by a heat exchange of said heat pipe.
7. A roller to be heated or cooled according to any one of claims 1 and 6, comprising:
a roller body (51);
one or more heat pipes (10) partly extending from said roller body (51); and
fins (13) provided at a partly extended portion of said heat pipes (10), so that said
roller is heated or cooled by a heat exchange of said pipes.
8. A roller to be heated or cooled according to claim 7, wherein said roller (50) further
comprises a case (55) to cover said fins (13) and an air fan (64) to ventilate a case.
9. A roller to be heated or cooled according to claims 7 or 8, wherein said roller (50)
further comprising a case (55) to cover said fins (13) and a heat/cool device (60)
using an electrical thermal element (61) at said case.
10. A roller to be heated or cooled according to claims 1 or 2, comprising:
a roller body (3); and
heat pipes (101, 102) partly extending from said roller body, said each heat pipe
(101, 102) having nearly half the length of said roller body (3) and being capable
of being inserted into said roller body (3) from both ends.