Heat exchange – Intermediate fluent heat exchange material receiving and... – Liquid fluent heat exchange material
Reexamination Certificate
2000-05-19
2002-03-26
Lazarus, Ira S. (Department: 3743)
Heat exchange
Intermediate fluent heat exchange material receiving and...
Liquid fluent heat exchange material
C165S185000, C165S080400, C361S700000, C174S015200
Reexamination Certificate
active
06360813
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a cooling apparatus for electronic components, such as a transistor for a power supply circuit. Particularly, it relates to an electronic component cooling system which has sufficient coolability, even when a heat radiating portion having a plate fin type radiator is spaced apart from the electronic component, and has high flexibility in design.
BACKGROUND OF THE INVENTION
Recently, the integration and installation density of electronic components have been increasingly higher. Accordingly improvement in cooling efficiency of the electronic components has become more important. Especially, so called power ICs, such as an IGBT (Insulated Gate type Bipolar Transistor), are not only used for signal transfer but also for supplying drive power to other components, so that they produce a large amount of heat. Thus, it is difficult to cool them.
FIG. 10
is a schematic perspective view of a conventional air-cooled electronic components cooling apparatus
501
.
In this conventional example, four printed boards
519
having electronic components mounted thereon (Integrated Circuits and the like, not shown) are arranged in parallel. At each top and bottom end of the boards
519
, a plate-fin type radiator
5
(a heat radiating portion)
511
,
515
is disposed. Each of the plate-fin type radiators
511
,
515
has honeycomb shaped vent holes
511
a
and
515
a
, through which air flows in the arrow direction in FIG.
10
. Most of the heat produced by the elements on the boards
519
is transferred through the boards
519
and then to the plate-fin type radiators
511
,
515
and finally to be radiated into the outside air. In order to improve the heat conduction through the boards
519
, an aluminum plate (not shown) may be embedded in the boards.
In the conventional electronic component cooling apparatus shown in
FIG. 10
, the plate-fin type radiator
511
,
515
has to be disposed around the boards
519
and in contact with the boards
519
. So, flexibility in design is poor, and because of the large volume of the plate-fin type radiator
511
,
515
, the whole apparatus becomes bulky.
When improvement in the coolability is required, in a case where the size of the whole apparatus is limited, it is necessary to increase the air flow (enlarging the size of a fun or increasing the rotation speed of the fun, or the like). That is because, in most cases, there is little probability to decrease the temperature at the radiator inlet portion, and there is a limit in improving the efficiency of the radiator itself. Under the condition where it is impossible to increase the air flow, the volume or size of the radiator has to be increased to enlarge the whole apparatus volume. Thus, in the above case, design flexibility is poor.
FIG. 11
is a schematic side-sectional view of a conventional water-cooled electronic component cooling apparatus
401
.
In this conventional example, a water-cooled heat exchanger
611
is disposed around boards
619
. In the water-cooled heat exchanger
611
, a honeycomb shaped water conduit
611
a
is formed within which a cooling water (coolant) flows.
The water-cooled electronic component cooling apparatus shown in
FIG. 11
has large a heat transfer capacity and has a higher coolability than the air-cooled apparatus shown in FIG.
10
. However, the water-cooled electronic component cooling apparatus of
FIG. 11
requires a water-cooling facility, such as a circulation pipe line for cooling water, a heat exchanger, and the like. So, since the apparatus becomes large and complicated and the system configuration requires more elements than the air-cooled type, the whole facility of the water-cooling system becomes complicated.
And, when improvement in coolability is required, in a case where the size of the whole apparatus is limited, it is necessary to increase the water flow (enlarging the size of a pump or increasing the rotation speed of the pump, or the like). This is because, in most cases, there is little probability to decrease the temperature at the radiator inlet portion, and there is a limit in improving the efficiency of the radiator itself. Under the condition where it is impossible to increase the water flow, the volume of the radiator has to be increased to thereby enlarge the whole apparatus. Thus, like the air-cooled type, design flexibility is also poor.
In view of the above problems, the object of the present invention is to provide an electronic component cooling apparatus which has sufficient coolability even when the heat radiating portion having a plate-fin type radiator is spaced apart from an electronic component, and which has high design flexibility.
SUMMARY OF THE INVENTION
In order to solve the above-mentioned problems, a cooling apparatus according to the present invention, for cooling an electronic component or boards on which the electronic component is mounted, comprises an air-cooled or water-cooled heat radiating portion and a meandering capillary tube heat pipe arranged to transfer heat between the above-mentioned electronic component or the board and the heat radiating portion.
Meandering capillary tube heat pipes have a very large heat transfer capability and are able to transfer heat along a long distance with a low thermal resistance. Therefore, even when the distance between the heat radiating portion and the electronic component or the board on which the electronic component is mounted becomes long, the temperature rise of the electronic component and the like can be suppressed. Therefore, it is possible to separate the board apart from the heat radiating portion, thus improving flexibility in arrangement of the electronic component or the heat radiating portion, so that various shaped apparatus can be designed and manufactured. And, a higher-density mounting of electronic components (Integrated Circuits and the like) is achieved and thus miniaturization of the apparatus is achieved.
In this specification, the term meandering capillary tube heat pipe means a heat pipe which has the following characteristics (disclosed in Japanese Laid-open Patent Publication No. Hei 4 (1992)-190090(U.S. Pat. No. 5,219,020 (Jun. 15,1993)), the entire contents of which are incorporated herein by reference).
(1) The meandering capillary tube heat pipe comprises a capillary that is sealed off from the outside.
(2) One part of the capillary acts as a heat radiating portion, and another part acts as a heat receiving portion.
(3) The heat receiving portion and the heat radiating portion are alternately arranged, and between them the capillary meanders.
(4) In the capillary, a two-phase condensable working fluid is sealed.
(5) The capillary has a diameter less than a maximum diameter which allows the two-phase condensable working fluid to circulate and move while being sealed inside of the capillary.
Examples of this type of meandering capillary tube heat pipe are disclosed in Japanese Laid-open Patent Publication No. Hei 4 (1992)-190090 (U.S. Pat. No. 5,219,020 (Jun. 15,1993)), No. Hei 7 (1995)-63487 (U.S. Pat. No. 5,697,428 (Dec. 16,1997)) and No. Hei 9 (1997)-49692 (U.S. Pat. No. 5,737,840 (Apr. 14, 1998)). Among them, in the latter two Japanese Patent Publications, the meandering capillary is embedded in a comparatively thin flat plate (thus called a plate-type heat pipe). If such a plate type heat pipe is adapted, it is easy to design and assemble connecting portions with a board and a heat radiating portion (a plate-fin type radiator and the like). The plate type heat pipe disclosed in Japanese Laid-open Patent Publication No. Hei 9 (1997)-49692(U.S. Pat. No. 5,737,840 (Apr. 14,1998)) uses, as a material, an aluminum extruded material which has many small channels, thereby reducing the material cost and machining cost.
In the electronic component cooling apparatus according to the present invention, it is preferable that the heat radiating portion comprises a set of radiation fins with an outer-shape of a substantially flat plate (plate fin type radiator)and the meandering capillary tube heat pi
Amako Kiyoo
Katoh Takahiro
Frishauf, Holtz Goodman, Langer & Chick, P.C.
Lazarus Ira S.
McKinnon Terrell
TS Heatronics Co., Ltd.
LandOfFree
Electronic components cooling apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electronic components cooling apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electronic components cooling apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2874483