[DESCRIPTION]
[Title of Invention]
CONNECTING STRUCTURE OF COOLING DEVICE, COOLING DEVICE,
AND METHOD FOR CONNECTING COOLING DEVICE
5 [Technical Field]
[OOOl]
The present invention relates to connecting structures for
connecting cooling dcvices to semiconductor devices, electronic devices,
and the like, in particular, to a connecting structure of a cooling device, a
10 cooling device, and a method for connecting a cooling device using a
phase-change cooling system in which the heat transportation and heat
radiation are performed by a phase-change cycle of vaporization and
condensation of a refrigerant.
[Background Art]
IS [OOO2]
In recent days, with the progress of high performance and high
functionality in semiconductor devices and electronic devices, the amount
of heat generation from them has been increasing. Therefore, a cooling
device with high heat transportation capability has been requircil The
20 cooling device using a phase-change cooling system in which the heat
transportation and heat radiation are performed by a phase-change cycle of
vaporization and condensation of a refrigerant makes it possible to
improve the heat transportation capability compared to a heat sink and the
lilce. The cooling device is therefore expected as a cooling device for the
25 semiconductor device and the electronic device with a large amount of heat
generation.
[OOO3]
An example of the cooling device using the phase-change cooling
system (hereinafter, also referred to as "a phase-change cooling device") is
2
described in Patent Literature 1. The related phase-change cooling device
described in Patent Literature 1 is used in order to cool a semiconductor
device as a heat generation source such as a CPU (central processing unit)
mounted on a circuit board. The related phase-change cooling device
5 includes an evaporating unit attached on the surface of a semiconductor
device and a condenser having a radiator, and between those are attached a
pair of conduits composed of a vapor tube and a liquid return tube. The
related phase-change cooling device is made to keep its inside to be a
reduced (low) pressure condition of approximately one-tenth of the
10 atmospheric pressure, and configures a thermosiphon which can circulate a
refrigerant without external motive force such as an electro-motive pump
due to the phase change of the water of a liquid refrigerant.
[OOO4]
In the related phase-change cooling device, the heat generated in
15 the semiconductor device of a heat generation source is transferred to the
evaporating unit. As a result, in the evaporating unit, the water of the
liquid refrigerant is boiled and evaporated under the reduced pressure due
to the transferred hcat, and the generated vapor is guided from the
evaporating unit into the condenser through the vapor tube. In the
20 condenser, the refrigerant vapor is cooled by an air blown by a cooling fan
to becorne liquid (water), and then it turns back into the evaporating unit
again through the liquid return tube due to the gravity.
[OOOS]
On the other hand, with electronic devices being miniaturized and
25 made thinner, a connecting structure is required which connects the
cooling device to the semiconductor device corresponding to miniaturizing
and making thinner. Patent Literature 2 describes an example of the
connecting structure of the cooling device to be mounted on the electronic
device which can be made thinner.
[0006]
The related electronic apparatus described in Patent Literature 2
includes in housing, a circuit board, first and second heating elements,
first and second sub heat pipes, a main heat pipe, first and second pressing
5 members, a heat sink, and a cooling Fan. The first pressing member presses
a first portion of the first sub heat pipe to the first heating element and
strengthens the thermal connection between the first sub heat pipe and the
first heating element. At this time, the first sub heat pipe is pressed to the
first heating element by the first pressing member and can be bent
10 following the inclination or the shape of a die of the first heating element.
Therefore, the first sub heat pipe is less likely to come into partial contact
with the die of the First heating element.
[0007]
In the related electronic apparatus, the main heat pipe with a
15 relatively large length, a relatively large thiclzness, and high heat transport
performance is arranged at a position offset from the heating element, and
the sub heat pipe is provided between the main heat pipe and the heating
element. That is to say, in the related electronic apparatus, the
plate-shaped sub heat pipe with a small thickness is overlapped on the
20 circuit board and the heating element, and the main heat pipe with a
relatively large thickness is arranged in a region where it does not overlap
with the heating element. It is said that the configuration makes it possible
to reduce the overall thickness of a heat radiating structure and thus reduce
the thickness of the electronic apparatus.
25 [Citation List]
[Patent Literature]
[0008]
[PTL 11
Japanese Patent Application Laid-Open No. 201 1-047616 (paragraphs
[0023] to [0049], FIG. 1)
[PTL 21
Japanese Patent Application Laid-Open No. 201 1-106793 (paragraphs
5 [0011] to [0079], FIGS. 2 to 5)
[Summary of Invention]
[Technical Problem]
[0009]
In the electronic apparatus described in Patent Literature 2, the sub
10 heat pipe is formed with a small thickness so that the sub heat pipe may be
flexibly deformed according to the inclination of the die or the shape of the
surface of the heating element when the sub heat pipe is closely adhered to
the heating element. However, since high heat transport performance
cannot be obtained using the thinned heat pipe, there has been a problem
15 that the cooling performance of the electronic device decreases.
[OO 1 01
On the other hand, in the related phase-change cooling device
described in Patent L,iterature 1, the high heat transport performance can
be obtained compared to the heat pipe because the refrigerant moves as a
20 gas-liquid two-phase flow. The evaporating unit of the related
phase-change cooling device is configured to be in the form of a firm box
using a metal such as copper superior in thermal conductivity in order to
store a sufficient amount of refrigerant and prevent the deformation due to
the increase in the internal pressure of a vapor-state refrigerant. Since an
25 evaporating unit like this does not have mechanical flexibility, a partial
contact or unequal loading arises between the evaporating unit and the
heating element due to variation in shapes of the evaporating unit and the
heating element. Therefore, there has been a problem that it is i~npossible
to obtain sufficient cooling performance due to the increase in thermal
resistance at the interface between the evaporating unit and the heating
element.
[OOI I]
Thus, the related cooling device, seelting high heat transport
5 performance, has a problem that it is impossible to obtain sufficient
cooling performance due to the increase in thermal resistance with a
heating element to be cooled.
[OO 121
The object of the present inventions is to provide a connecting
10 structure of a cooling device, a cooling device, and a method for
connecting a cooling device that solve the problem mentioned above that it
is impossible in a cooling device using a phase-change system, seelting
high heat transport performance, to obtain sufficient cooling performance
due to the increase in thermal resistance with a heating element to be
15 cooled.
[Solution to Problem]
[0013]
A connecting structure of a cooling device according to an
exemplary aspect of the present invention includes a connecting board with
20 an opening; a pressing plate of thin plate elastically deformable; first
fixing means for fixing the pressing plate to the connecting board with the
pressing plate disposed covering heat receiving means composing the
cooling device; and second fixing means for fixing the connecting board to
a substrate with the heat receiving means abutting against a heating
25 element mounted on the substrate and disposed in the opening.
[0014]
A cooling device according to an exemplary aspect of the present
invention includes heat receiving means for storing a refrigerant and
receiving the heat from a heating element; a connecting board with an
opening; a pressing plate of thin plate elastically deformable; first fixing
means for fixing the pressing plate to the connecting board with the
pressing plate disposed covering the heat receiving means; and second
fixing means for fixing the connecting board to a substrate with the heat
5 receiving means abutting against a heating element mounted on the
substrate and disposed in the opening.
[00 151
An electronic device using a cooling device according to an
exemplary aspect of the present invention includes a substrate; a heating
10 element mounted on the substrate; heat receiving means for storing a
refrigerant and receiving the heat from the heating element; a connecting
board with an opening; a pressing plate of thin plate elastically
deformable; first fixing means for fixing the pressing plate to the
connecting board with the pressing plate disposed covering the heat
15 receiving means; second fixing means for fixing the connecting board to
the substrate with the heating element and the heat receiving means
disposed in the opening: heat radiating means for radiating heat by
condensing and liquefying a vapor-state refrigerant vaporized in the heat
receiving means; and a pipe connecting the heat radiating means to the heat
20 receiving means, wherein the first fixing means fixes the pressing plate to
the connecting board with the heat receiving means abutting firmly against
the heating element, and the second fixing means fixes the connecting
board to the substrate with the heat receiving means abutting firmly against
the heating element.
25 [OO16]
A method for connecting a cooling device according to an
exemplary aspect of the present invention includes forming a connecting
board with an opening; disposing a heat receiving unit that composing a
cooling device in the opening; disposing a pressing plate of thin plate
elastically deformable so as t o cover the heat receiving unit; connecting
the pressing plate to the connecting board; and disposing the connecting
board on a substrate on which a heating element is mounted so that the
heating element may be housed in the opening.
5 [Advantageous Effects of Invention]
[00 171
According to the connecting structure of a cooling device of the
present invention, it is possible in a cooling device using a phase-change
system to obtain sufficient cooling performance even when configured to
10 obtain high heat transport performance.
[Brief Description of Drawings]
(00 1 81
[FIG. 11
FIG. 1 is a cross-sectional view illustrating a connecting structure of a
15 cooling device in accordance with the first exemplary embodiment of the
present invention.
[FIG. 2A]
FIG. 2A is a perspective view illustrating a configuration of a cooling
device in accordance with the second exemplary embodiment of the present
20 invention.
[FIG. 2B]
FIG. 2B is a side view illustrating the configuration of the cooling device
in accordance with the second exemplary embodiment of the present
invention.
25 [FIG. 3A]
FIG. 3A is a perspective view illustrating a configuration of an electronic
device using a cooling device in accordance with the third exemplary
embodiment of the present invention.
[FIG. 3BI
FIG. 3B is a side view illustrating the configuration of the electronic
device using the cooling device in accordance with the third exemplary
embodiment of the present invention.
[FIG. 41
5 FIG. 4 is a perspective view illustrating a part of another configuration of
the electronic device using the cooling device in accordance with the third
exemplary embodiment of the present invention.
[FIG. 51
FIG. 5 is a perspective view illustrating a part of yet another configuration
10 of the electronic device using the cooling device in accordance with the
third exemplary embodiment of the present invention.
[Description of Embodiments]
[0019]
The exemplary embodiments of the present invention will be
15 described with reference to drawings below.
[0020]
[The first exemplary embodiment]
FIG. 1 is a cross-sectional view illustrating a connecting structure
of a cooling device 100 in accordance with the first exemplary embodiment
20 of the present invention. The connecting structure of the cooling device
100 includes a connecting board 11 0 with an opening 11 1, a pressing plate
120 or thin plate elastically deformable, a first fixing unit 130, and a
second fixing unit 140. The first fixing unit 130 fixes the pressing plate
120 to the connecting board 110 with the pressing plate 120 disposed
25 covering a heat receiving unit 210 composing the cooling device. The
second fixing unit 140 fixes the connecting board 110 to a substrate 310
with the heat receiving unit 210 abutting against a heating elenlent 320
mounted on the substrate 3 10 and disposed in the opening 11 1.
[0021]
9
Part of the pressing plate 120 elastically deforms as a plate spring
due to the action of the first fixing unit 130. This makes the variation in
shape of the heat receiving unit 210 absorbed. At this time, the second
fixing unit 140 fixes the heat receiving unit 210 to the heating element 320
8 with abutting against each other, which makes it possible to press the
whole contact surface between the heating element 320 and the heat
receiving unit 210 by equal force. According to the connecting structure of
the cooling device 100 of the present exemplary embodiment, it is
unnecessary for the heat receiving unit 210 to have the mechanical
10 flexibility in order to be attached firmly to the heating element, unlike in
the case of the related electronic device described in Patent Literature 2.
That is to say, it becomes possible to use a heat receiving unit having a
robust container as the heat receiving unit 210. It is therefore possible to
use the connecting structure of the cooling device 100 of the present
1s exemplary embodiment for a phase-change cooling device which can obtain
high heat transport performance.
[0022]
The pressing plate 120 can be configured to include a cutout section
where a portion of it is cut away. This makes it possible to adjust the
20 elastic deformation amount in a situation where the pressing plate 120
covers the heat receiving unit 210. The second fixing unit 140 can be
configured to include a fastening section and a spring section. By using a
spring, it becomes easier to control the second fixing unit 140 so as to
press the whole contact surface between the heating element 320 and the
25 heat receiving unit 210 by equal force.
I
[0023]
According to the method for connecting a cooling device of the
present exemplary embodiment, first, a connecting board with an opening
is formed, and a heat receiving unit composing a cooling device is disposed
in the opening. A pressing plate of thin plate elastically deformable is
disposed so as to cover the heat receiving unit, and the pressing plate is
connected to the connecting board. Next, the connecting board is disposed,
on a substrate on which a heating element is mounted, so that the heating
5 element may be housed in the opening. Further, with the heat receiving unit
made to abut firmly against the heating element, the pressing plate is fixed
to the connecting board, and the connecting board is fixed to the substrate.
[0024]
According to the connecting structure of a cooling device 100 and
10 the method for connecting a cooling device of the present exemplary
embodiment, the above-mentioned configuration makes it possible in a
cooling device using a phase-change system to obtain sufficient cooling
performance even when configured to obtain high heat transport
performance.
15 [0025]
[The second exemplary embodiment]
Next, the second exemplary embodiment of the present invention
will be described. FIG. 2A and FIG. 2B are diagrams i l l u s t r a t i n ~a
configuration of a cooling device 1000 in accordance with the second
20 exemplary embodiment of the present invention, FIG. 2A is a perspective
view, and FIG. 2B is a side view. The cooling device 1000 includes a heat
receiving unit 210 storing a refrigerant and receiving the heat from a
heating element, the connecting board 110 with an opening, the pressing
plate 120 of thin plate elastically deformable, the first fixing unit 130, and
25 the second fixing unit 140. The first fixing unit 130, as shown in FIG 1,
fixes the pressing plate 120 to the connecting board 110 with the pressing
plate 120 disposed covering the heat receiving unit 210. The second fixing
unit 140 fixes the connecting board 110 to the substrate 310 with the heat
receiving unit 210 abutting against a heating element mounted on the
substrate and disposed in the opening.
[0026]
The cooling device 1000 further includes a heat radiating unit 220
5 radiating heat by condensing and liquefying a vapor-state refrigerant
vaporized in the heat receiving unit 210, and a pipe connecting the heat
radiating unit 220 to the heat receiving unit 210. The heat radiating unit
220 can be disposed on the connecting board 110. The pipe includes a first
pipe 231 connecting antupper part of the heat receiving unit 210 to an
10 upper part of the heat radiating unit 220, and a second pipe 232 connecting
a side surface of the heat receiving unit 210 to a lower part of the heat
radiating unit 220.
[0027]
It is possible in the cooling device 1000 to always keep the inside
15 of the heat receiving unit 210 in the saturated vapor pressure of the
refrigerant by using a low-boiling material as a refrigerant and evacuating
the heat receiving unit 210 after enclosing the refrigerant in it. It is
possible to use as thc refrigerant a low-boiling refrigerant such as
hydrofluorocarbon and hydrofluoroether, for example, which are insulating
20 and inactive materials. It is possible to use the metal having an excellent
thermal conductive property such as aluminum and copper, for example, for
the material composing the heat receiving unit 210 and the heat radiating
unit 220.
[0028]
25 The cooling device 1000 is used with the heating element such as a
CPU (central processing unit), for example, disposed on the undersurface
of the heat receiving unit 210, and thermally connected to the heat
receiving unit 210. The heat from the heating element is transferred to the
refrigerant through the heat receiving unit 210, and then the refrigerant
vaporizes. At this time, since the refrigerant draws the heat from the
heating element as the vaporization heat, a rise in temperature of the
heating element is avoided.
[0029]
5 The vapor-state refrigerant vaporized in the heat receiving unit 210
flows into the heat radiating unit 220 through the first pipe 231. The
vapor-state refrigerant radiates heat in the heat radiating unit 220 and
condenses and liquefies. As described above, the cooling device 1000 is
conligured using the phase-change cooling system in which the heat
10 transportation and heat radiation are performed by a cycle of vaporization
and condensation of a refrigerant.
[0030]
The cooling device 1000 according to the present exemplary
embodiment is configured to attach a phase-change type cooler in which
15 the heat receiving unit 210 is connected to the heat radiating unit 220 by
the pipes 23 1 and 232 to the connecting board 110 with the opening. When
the pressing plate 120 is connected to the connecting board 110, part of the
pressing plate 120 elastically deforms as a plate spring due to thc action of
the first fixing unit 130. This makes the variation in shape of the heat
20 receiving unit 210 absorbed. At this time, the second lixing unit 140 fixes
the heat receiving unit 210 to the heating element with abutting against
each other, which makes it possible to press the whole contact surface
between the heating element 320 and the heat receiving unit 210 by equal
force. Therefore, it is possible to decrease the thermal resistance at an
25 interface between the heat receiving unit 210 and the heating element and
to obtain sufficient cooling performance.
[003 11
According to the method for connecting a cobling device of the
present exemplary embodiment, first, the connecting board 110 with an
opening is formed, and the heat receiving unit 210 composing a cooling
device is disposed in the opening. The heat radiating unit 220, which
radiates heat by condensing and liquefying a vapor-state refrigerant
vaporized in the heat receiving unit, is disposed on the connecting board
5 110, and the heat radiating unit 220 is connected to the heat receiving unit
210 by a pipe.
[0032]
Next, the pressing plate 120 of thin plate elastically deforrnable is
disposed so as t o cover the heat receiving unit 210, and the pressing plate
10 120 is connected to the connecting board 110. And then, the connecting
board 110 is disposed, on a substrate on which a heating element is
mounted, so that the heating element may be housed in the opening.
Further, with the heat receiving unit 210 made to abut firmly against the
heating element, the pressing plate 120 is fixed to the connecting board
15 110, and the connecting board 110 is fixed to the substrate.
[0033]
According to the cooling device 1000 and the method for
connecting a cooling device of the present exemplary embodimctlt, the
above-mentioned configuration makes it possible in a cooling device using
20 a phase-change system to obtain sufficient cooling performance even when
configured to obtain high heat transport performance.
[0034]
Next, the cooling device 1000 according to the present exemplary
embodiment will be described in more detail.
25 [0035J
The phase-change cooler composing the cooling device 1000
according to the present exemplary embodiment is composed of the heat
receiving unit 210 receiving the heat Srorn a heating element and turning a
refrigerant stored inside into a vapor state by the phase-change, and the
heat radiating unit 220 drawing heat from the vapor-state refrigerant using
a fan and the like placed outside and turning it into a liquid state by the
phase-change. The heat receiving unit 210 is connected to the heat
radiating unit 220 by two pipes, that is, the first pipe 231 and the second
5 pipe 232. Since the phase-change cooler circulates a refrigerant using the
action of gravity, the heat radiating unit 220 is configured to include a part
located above the heat receiving unit 210 in the vertical direction.
[0036]
As shown in FIG. 2A and FIG. 2B, the cooling device 1000
10 according to the present exemplary embodiment includes the
above-mentioned phase-change cooler, the connecting board 110 having
the opening in which the cooler is disposed, and the pressing plate 120.
The pressing plate 120 is disposed so as to cover a surface opposite to the
surface of the heat receiving unit 210 abutting against a heating element
15 with the heat receiving unit 210 of the phase-change cooler disposed in the
opening of the connecting board 110.
[0037]
The connecting board 110 has enough thickness for a large
deformation not to arise by the force which makes the heat receiving unit
20 210 abut firmly against the heating element and is generated due to the
action of the first fixing unit 130. The opening of the connecting board 110
houses the heat receiving unit 210. The opening can be about the same size
as a surface where the heat receiving unit 210 is connected to the heating
element. It is desirable to be a size where the outline of the heat receiving
25 unit 210 is extended by 0.05inm to 0.2mm, preferably. This configuration
makes it possible to attach the heat receiving unit 210 to the heating
element properly. That is to say, it is possible to avoid the situations that a
gap of the arrangemcnt position of the heat receiving unit 210 occurs in the
in-planc direction of the contact surface and therefore the area of the
surface decreases where the heat receiving unit 210 abuts firmly against
the heating element.
[0038]
The connecting board 110 includes a screw hole to fix the pressing
5 plate 120 in the area peripheral to the opening, for example. The screw
hole composes a part of the first fixing unit 130. The connecting board 110
has holes, into which fastening parts necessary for fastening it to the
substrate or a chassis are inserted, near the outer periphery, for example,
near four corners of the square shape. The holes compose a part of the
10 second fixing unit 140. By means of the fastening member such as the
holes and screws, the connecting board 11 0 on which the phase-change
cooler is disposed is fastened to the substrate.
[0039]
As shown in FIG. 2A and FIG. 2B, the heat radiating unit 220 of the
1s above-mentioned phase-change cooler is disposed on the connecting board
110 This configuration makes it possible to distribute the force which is
applied to the heat radiating unit 220 to the connecting board 110.
Therefore, when thc lorce is applied from the outside to the cooling device
of the present exemplary embodiment, it becomes possible to reduce the
20 force acting on a connection of the pipe where has low mechanical
strength.
[0040]
In contrast, in the related phase-change cooling device described in
Patent Literature 1, although the evaporating unit (heat receiving unit) is
25 fixed on the surface of the se~niconductord evice, the condenser (heat
radiating unit) is not fixed on the chassis and is supported only by the pipe
connecting the heat receiving unit to the heat radiafing unit. Therefore,
there has been a problem that the pipe is easy to damage and it is likely to
affect the operations of the phase-change cooler if some impacl is applied
to the heat radiating unit from the outside. According to the cooling device
1000 of the present exemplary embodiment, however, such problem can be
avoided as mentioned above.
[0041]
In the related phase-change cooling device described in Patent
Literature 1, there has been a problem that the cooling performance
decreases because of an increase in the thermal resistance at the interface
between the heat receiving unit and the heating element i f the evaporating
unit (heat receiving unit) is mounted on the surface of the semiconductor
device. That is to say, in the related heat receiving unit described in Patent
Literature 1, the center of gravity is located off-center due to its own
weight of the heat radiating unit connected by the pipe. Therefore, the
reason of the problem is because it is difficult to keep parallel the contact
surface between the heat receiving unit and the heating element when the
heat receiving unit is mounted on the surface of the semiconductor device.
According to the cooling device 1000 of the present exemplary
embodiment, however, the heat radiating unit 220 is disposed on the
connecting board 11 0 and the connecting board 110 supports the heat
radiating unit 220, as mentioned above. This makes it possible to reduce
the influence of its own weight of the heat radiating unit which the heat
receiving unit 210 is subject to. According to the cooling device 1000 of
the present exemplary embodiment, therefore, it is possible to avoid the
problem that the cooling performance decreases because the contact
surface between the heat receiving unit and the heating element tilts due to
its own weight of the heat radiating unit.
[0042]
As mentioned above, the pressing plate 120 is attached to the
connecting board 110 and attached so as to cover the surface opposite to
the contact surface between the heat receiving unit 210 and the heating
element. The pressing plate 120 is preferably configured using a metal with
a shape of thin plate, but it is not limited to this as long as it is a material
elastically deformable.
[0043]
5 By forming the pressing plate 120 using an elastic body with a
shape of thin plate, it is possible to absorb minute irregularities occurring
due to the production tolerance of the heat receiving unit 210 and the
heating element when the heat receiving unit 210 is made to abut firmly
against the heating element. It becomes, therefore, possible to press the
10 heat receiving unit 210 equally against the contact surface of the heating
element. At this time, the position of the heat receiving unit 210 can be
shifted with absorbing minute irregularities. Even i f this is the case,
however, the operations of the cooling device 1000 are not affected
because the pipe absorbs the shift. That is to say, since the pipe connecting
15 the heat receiving unit 210 to the heat radiating unit 220 is configured to
be deforrnable in response to bending, the deformation of the pipe makes it
possible to absorb the position shift of the heat receiving unit 210. It is
also acceptable that the pressing plate 120 is configured to include a cutout
section where a portion of it is cut away to make the elastic deformation
20 amount adjustable, by which the position shift of the heat receiving unit
210 is absorbed. Further, it is also possible to absorb the position shift of
the heat receiving unit 210 by adjusting the position of the heat radiating
unit 220 disposed on the connecting board 110. Specifically, for example,
it is possible to incline a radiator composing the heat radiating unit 220
25 depending on the position variation of the heat receiving unit 210.
[0044]
Next, the effect of the cooling device 1000 of the present exemplary
embodiment will be further described.
100451
According to the present exemplary embodiment, it becomes easier
to perform a task of mounting the cooling device 1000 on the heating
element disposed on the substrate. The reason is because it is possible to
mount the heat receiving unit 210 on the heating element by fixing the
5 connecting board 110 to the substrate or the chassis. The pressing plate 120,
which has characteristics of spring to press the heat receiving unit 210,
makes it possible to press the contact surface between the heating element
and the heat receiving unit 210 by equal force.
[0046]
10 Even if the impact force is applied to the heat radiating unit 220
from the outside, the pipe becomes less damaged. If the impact is applied
to the heat radiating unit 220 from the outside, part of the impact reaches
to the connecting board 110 on which the heat radiating unit 220 is fixed
and is transferred to the substrate or the chassis through the fastening
15 member. This makes it possible to decrease the probability that the pipe is
damaged.
[0047]
According to the present exemplary embodiment, the degree of
freedom of attaching the phase-change cooler increases and the versatility
20 of using the phase-change cooler is expanded. The reason is as follows.
The connecting board 110 is fixed on the substrate or the chassis by means
of the fastening member. As a result, even if the sizes of the fixing holes
and the position between the fixing holes, which are formed in the
substrate or the chassis, are modified, it is possible to respond to the
25 modification only by changing the connecting board 110.
[0048]
Further, according to the present exemplary embodiment, it is
possible to simplify the process for mounting the phase-change cooler.
The phase-change cooler needs to work on the condition that the
refrigerant is encapsulated and sealed inside. It is therefore necessary to
weld the pipe to the heat receiving unit and the heat radiating unit in
advance by brazing technique and the like and to seal a refrigerant inlet
after encapsulating the refrigerant. A swage, a weld, or a valve is generally
5 used for the sealing process. However, since the configuration of the
phase-change cooler is complicated, there is the potential for significant
difficulty in the process for mounting the phase-change cooler. That is to
say, trying to makc a hole to fix the heat receiving unit or the hcat
radiating unit on the substrate after the process for sealing, there is the
10 potential for the situation that tools cannot be placed at the position
desired. According to the present exemplary embodiment, however, it is
possible to attach the heat receiving unit 210 composing the phase-change
cooler only by the process for arranging i t in the opening 11 1 of the
connecting board 110 and pressing it by the pressing plate 120. This makes
15 it possible to mount the phase-change cooler easily.
[0049]
[The third exemplary embodiment]
Next, the third exemplary embodiment of the present invention will
be described. FIG. 3A and FIG. 3B are diagrams illustrating a
20 configuration of an electronic device using a cooling device 2000 in
accordance with the third exemplary embodiment of the present invention,
FIG. 3A is a perspectivc view, and FIG. 3B is a side view. 'The electronic
device using a cooling device 2000 includes a substrate 310, a heating
element 320 mounted on the substrate 310, the heat receiving unit 210, heat
25 radiating unit 220, and the pipe 230 connecting the heat receiving unit 210
to the heat radiating unit 220. The heat receiving unit 210 stores a
refrigerant and receives the heat from the heating clement 320. The heat
radiating unit 220 condenses and liquefies the vapor-state refrigerant
vaporized in the heat receiving unit 210 and radiates heat.
20
[OOSO]
The electronic device using the cooling device 2000 further
includes the connecting board 110 with the opening 11 1, the pressing plate
120 of thin plate elastically deformable, the first fixing unit 130, and the
5 second fixing unit 140. The first fixing unit 130 fixes the pressing plate
120 to the connecting board 110 with the pressing plate 120 disposed
covering the heat receiving unit 210. At this time, the first fixing unit 130
fixes the pressing plate 120 to the connecting board 110 with the heat
receiving unit 210 abutting firmly against the heating element 320. The
10 second fixing unit 140 lixes the connecting board 110 to the substrate 310
with the heating element 320 and the heat receiving unit 210 disposed in
the opening 11 1. At this time, the second fixing unit 140 fixes the
connecting board 110 to the substrate 310 with the heat receiving unit 210
abutting firmly against the heating element 320.
15 [OOSl]
The electronic device using the cooling device 2000 according to
the present exemplary embodiment is configured to include a phase-change
cooler in which the heat receiving unit 210 is connected to the heat
radiating unit 220 by the pipe 230. As shown in FIG. 3A and FIG. 3B, in
20 the electronic device using the cooling device 2000 of the present
exemplary embodiment, the phase-change cooler fixed on the connecting
board 110 is implemented on the beating element 320 mounted on the
substrate 310. An electronic circuit board mounting electronic components
such as CPUs, for example, a mother board can be used as the substrate
25 310.
[0052]
The phase-change cooler is fixed to the heating element 320
through the connecting board 11 0 and the second fixing unit 140.
Specifically, for example, the second fixing unit 140 is configured to
include holes formed in the connecting board 110 and a fastening section
loaded into the holes. At this time, as shown in FIG. 4, the second fixing
unit 140 can be configured to include a fastening section 141 such as a
screw and a spring section 142. By using a spring, it becomes easier to
5 control the pressure by which to press the heating element 320 and the heat
receiving unit 210 and to make them attached firmly to each other. It
becomes possible by the action of the pressing plate 120 in addition to the
above to absorb the effect of the concavo-convex shape due to the
production tolerance of the heat receiving unit 210 and the heating element
10 320 and to press the contact surface between the heating element 320 and
the heat receiving unit 210 by more equal force.
[0053]
As shown in FIG. 5, when the heat radiating unit 220 is disposed on
the connecting board 110, it is also acceptable to attach an L-shaped fixed
Is plate 222 to the heat radiating unit 220 and fix it to the connecting board
110 by the fastening member. In this case, it is preferable to form the fixed
plate 222 using a thin metal plate elastically deformable. The reason is as
follows. In order for the equal force to act at the contact surface when the
heat receiving unit 210 is pressed toward the heating element by means of
20 the pressing plate 120, the pressing plate 120 need to deform to absorb the
variation in shape of the heat receiving unit 210. The reason is because the
heat radiating unit 220 connected to the heat receiving unit 210 through the
pipe 230 needs to have range of motion.
[0054]
25 As mentioned above, according to the electronic device using the
cooling device 2000 of the present exemplary embodiment, it is possible to
decrease the thermal resistance at the interface between the heat receiving
unit and the heating element because they are fixed firmly with the whole
contact surface between the heating element and the heat receiving unit
pressed by equal force. That is to say, even though the cooling device
using the phase-change system is used in which the heat receiving unit is
connected to the heat radiating unit by the pipe, it is possible to obtain the
electronic device having sufficient cooling performance.
5 [0055]
The present invention is not limited to the aforementioned
exemplary embodiments. Various modifications can be made therein within
the scope of the present invention as defined by the claims, and obviously,
such modifications are included in the scope of the present invention.
10 [0056]
This application is based upon and claims the benefit of priority lrom
Japanese Patent Application No. 2012-1 12498, filed on May 16, 2012, the
disclosure of which is incorporated herein in its entirety by reference.
[Reference Signs List]
I5 [0057]
100 connecting structure of a cooling device
11 0 connecting board
111 opening
120 pressing plate
20 130 first fixing unit
140 second fixing unit
14 1 fastening section
142 spring section
210 heat receiving unit
25 220 heat radiating unit
222 fixed plate
230 pipe
231 first pipe
232 second pipe
310 substrate
320 heating element
1000 cooling device
2000 electronic using cooling device
[CLAIMS]
[Claim 11 A connecting structure of a cooling device, comprising:
a connecting board with an opening;
a pressing plate of thin plate elastically deformable;
5 first fixing means for fixing the pressing plate to the connecting
board with the pressing plate disposed covering heat receiving means
composing the cooling device; and
second fixing means for fixing the connecting board to a substrate
with the heat receiving means abutting against a heating element mounted
10 on ihe substrate and disposed in the opening.
[Claim 21 A cooling device, comprising:
heat receiving means for storing a refrigerant and receiving the heat
from a heating element;
15 a connecting board with an opening;
a pressing plate of thin plate elastically deformable;
first fixing means for fixing the pressing plate to the connecting
board with the pressing plate disposed covering the heat receiving means;
and
20 second fixing means for fixing the connecting board to a substrate
with the heat receiving means abutting against a heating element mounted
on the substrate and disposed in the opening.
[Claim 31 The cooling device according to claim 2, further comprising
25 heat radiating means for radiating heat by condensing and
liquefying a vapor-state refrigerant vaporized in the heat receiving means;
and
a pipe connecting the heat radiating means to the heat receiving
25
wherein the heat radiating means is disposed on the connecting
board.
!
[Claim 41 The cooling device according to claim 2 or 3,
5 wherein the pipe comprises a first pipe connecting an upper part of
the heat receiving means to an upper part of the heat radiating means, and a
second pipe connecting a side surface of the heat receiving means to a
lower part of the heat radiating means.
10 [Claim 51 The cooling device according to any one of claims 2, 3, and 4,
wherein the pressing plate comprises a cutout section where a
portion of the pressing plate is cut away.
[Claim 61 The cooling device according to any one of claims 2 , 3, 4, and 5,
15 wherein the second fixing means comprises fastening means and a
spring section.
[Claim 71 An electronic device using a cooling device, comprising:
a substrate;
20 a heating element mounted on the substrate;
heat receiving means for storing a refrigerant and receiving the heat
from the heating element;
a connecting board with an opening;
a pressing plate of thin plate elastically deformable;
25 first fixing means for fixing the pressing plate to the connecting
board with the pressing plate disposed covering the heat receiving means;
second fixing means [or fixing the connecting board to the substrate
with the heating element and the heat receiving means disposed in the
opening;
heat radiating means for radiating heat by condensing and
liquefying a vapor-state refrigerant vaporized in the heat receiving means;
and
a pipe connecting the heat radiating means to the heat receiving
5 means,
wherein the first fixing means fixes the pressing plate to the
connecting board with the heat receiving means abutting firmly against the
heating element, and
the second fixing means fixes the connecting board to the substrate
10 with the heat receiving means abutting firmly against the heating element.
[Claim 81 A method for connecting a cooling device, comprising:
forming a connecting board with an opening:
disposing a heat receiving unit that composing a cooling device in
15 the opening;
disposing a pressing plate of thin plate elastically deformable so as
to cover the heat receiving unit;
connecting the pressing plate to the connecting board; and
disposing the connecting board on a substrate on which a heating
20 element is mounted so that the heating element may be housed in the
opening.
[Claim 91 The method for connecting a cooling device according to claim 8,
further comprising:
25 fixing the pressing plate to the connecting board and fixing the
connecting board to the substrate, with the heat receiving unit made to abut
firmly against the heating element.
[Claim 101 The method for connecting a cooling device according to claim
8 or 9, further comprising:
disposing, on the connecting board, a heat radiating unit radiating
heat by condensing and liquefying a vapor-state refrigerant vaporized in
5 the heat receiving unit; and
connecting the heat radiating unit to the heat receiving unit by a
pipe.