Patent Application
20100326635
The present invention relates to heat-exchanging devices and heat generator casings using the heat-exchanging device.
If a current of several tens of amperes travels through an electric device, such as a receiver and transmitter used in a base station of mobile phones, the electric device generates heat by electricity. Therefore, electric devices are sometimes called heat generators. To reliably use this kind of electric device (hereafter referred to as “heat generator”), cooling of the heat generator becomes extremely important. Conventionally, a base station (hereafter referred to as “heat generator casing”) for mobile phones that contain the heat generator is configured as follows.
A conventional heat-exchanging device is described below with reference to drawings.
As shown in
Heat generated by heat generator 103 is transferred to heat-exchanging device 102 via internal airflow 107, which is generated by internal air fan 105, in the housing. In other words, internal air near heat generator 103 is drawn into internal air inlet 108 by operating internal air fan 105. The heat of internal air drawn in is released to external air, which is described later, while the internal air passes through heat exchanger 109. The internal air after releasing heat is blown out to heat generator 103 through internal air outlet 110.
If external air fan 106 is operated, a flow of external air drawn 112 in from outside the housing is established. In other words, the external air passing through external air inlet 111 absorbs heat from aforementioned internal air while the external air passes through heat exchanger 109. External air absorbing heat is blown outside the housing through external air outlet 113.
As illustrated in the drawing, internal air fan 105 and external air 106 are disposed at positions facing each other relative to heat exchanger 109 installed on a wall of housing 101. This structure slims heat generator casing 100, and reduces the space needed for installing heat generator casing 100.
However, further downsizing of the area for installing heat generator casing 100 is demanded.
Patent Literature 1: Japanese Patent Unexamined Publication No. 2000-161875
Patent Literature 2: Japanese Patent Unexamined Publication No. 2001-99531
A heat-exchanging device of the present invention includes a first air blower and a second air blower inside a first case.
The first case includes a first inlet, first outlet, second inlet, and second outlet. The first inlet draws in a first fluid. The first outlet is provided in a direction different from that facing the first inlet. The first outlet blows out the first fluid. The second inlet draws in a second fluid. The second outlet is provided in a direction different from that facing the second inlet. The second outlet blows out the second fluid. The first air blower makes the first fluid flow from the first inlet to the first outlet via a first path. This forms a first passage. The second air blower makes the second fluid flow from the second inlet to the second outlet via a second path. This forms a second passage. The first passage where the first fluid flows and the second passage where the second fluid flows exchange heat between the first fluid and the second fluid inside the heat exchanger.
If this heat-exchanging device is used in a heat generator casing, two flows are formed: The first fluid passing inside and outside of the heat generator casing, and the second fluid circulating in the heat generator casing.
Exemplary embodiments of the present invention are described below with reference to drawings. However, the exemplary embodiments herein are illustrative, and thus the present invention is not limited to these exemplary embodiments.
A heat-exchanging device in the first exemplary embodiment of the present invention is described below with reference to
Case 2 includes inlet 6 that is the first inlet for drawing in external air as the first fluid, and outlet 7 that is the first outlet for blowing out external air that has passed through heat exchanger 3. Case 2 also includes inlet 8 that is the second inlet drawing in internal air as the second fluid, and outlet 9 that is the second outlet for blowing out internal air that has passed through heat exchanger 3. In the first exemplary embodiment, inlet 6 and outlet 7 for external air are provided on horizontally-adjacent side faces of case 2. Inlet 8 and outlet 9 for internal air are provided on a bottom face of case 2.
Heat exchanger 3 is described with reference to
Heat exchanger plate 10 is made of a thermoplastic resin film, such as polystyrene, polypropylene, and polyethylene. Other than these materials, heat exchanger plate 10 may be typically made of a metal plate, such as aluminum, paper with heat conductivity and moisture permeability, a microporous resin film, or paper in which resin is mixed.
Heat exchanger plate 10 is typically formed by vacuum forming, pressured forming, extreme-pressure forming, or press forming.
A centrifugal air blower is used for fan 4 and fan 5. In the first exemplary embodiment, fan 4 is provided between heat exchanger 3 and outlet 7. Fan 5 is provided between heat exchanger 3 and outlet 9. With this structure, fan 4 makes the external air passing through paths 12a in heat exchanger 3 flow in a direction perpendicular to path 12a. Accordingly, the external air drawn in from inlet 6 for external air passes along paths 12a, and flows to outlet 7. This flow of external air is passage 15 that is the first passage.
In the same way, fan 5 makes the internal air passing through paths 12b in heat exchanger 3 flow in a direction perpendicular to paths 12b. Accordingly, the internal air drawn in from inlet 8 for internal air passes through path 12b, and flows to outlet 9. This flow of internal air is passage 16 that is the second passage.
More specifically, in heat exchanging device 1 in the first exemplary embodiment, fan 4 is provided between heat exchanger 3 and outlet 7, and fan 5 is provided between heat exchanger 3 and outlet 9. This structure makes directions of paths 12a and 12b in heat exchanger 3 the same directions as those of rotating axes of fans 4 and 5 respectively. By reducing the number of bends in heat exchanging device 1, a pressure loss due to bends in passages 15 and 16 can be suppressed. As a result, an installation area of heat exchanging device 1 can be reduced. In addition, since fans 4 and 5 act to draw out the external air and internal air passing through paths 12a and 12b, reduction in a flow rate of external air and internal air in passages 15 and 16 is suppressed. Furthermore, inlets 6 and 8 and outlets 7 and 9 are provided at predetermined positions. Accordingly, passage 15 is formed horizontally, and passage 16 is formed vertically. As a result, heat exchanging device 1 builds a three-dimensional passage in horizontal and vertical directions.
Next, as shown in
Covers 20 and 21 are made of airtight elastic body formed of closed cell foam, such as ethylene propylene diene rubber foam (hereafter referred to as EPDM rubber foam), or the same material as steel plate configuring case 2. Air-tightness of inlets 8 and 18 or outlets 9 and 19 improve if they are covered with elastic body such as EPDM rubber foam.
With the above structure, heat-exchanging device 1a offers two installation directions by the single configuration. Heat-exchanging device 1a is disposed at symmetric positions in a heat generator casing. More specifically, heat-exchanging device 1a enables installation of symmetrical heat-exchanging devices at an upper part of the housing. The second fluid in the housing flows to the second passage, and exchanges the heat with the first fluid passing through the first passage. In this way, inside the housing is cooled down. As a result, an installation area of the heat generator casing can be reduced.
A heat generator casing using heat-exchanging device 1, which is described in the first exemplary embodiment, is described with reference to
Heat generator casing 30 includes case 32 that is the second case inside housing 31. Heat-exchanging device 33a that is the first heat-exchanging device, and heat-exchanging device 33b that is the second heat-exchanging device are disposed on case 32. Heat-exchanging device 33a uses first case 2a. Heat-exchanging device 33b uses third case 2b.
Housing 31 includes side face 34a that is the first wall, side face 34b that is the third wall, and rear face 35 that is the second wall. Opening 36a that is the first opening and opening 36b that is the third opening for drawing in external air are provided on side faces 34a and 34b. Opening 37 that is the second opening for blowing out the external air passing through heat-exchanging devices 33a and 33b, which is described later, is provided on rear face 35.
Heat generator 103, such as a receiver or transmitter of mobile phone, is housed in case 32.
As shown in
On the other hand, as shown in
The internal air exchanges heat with external air while the internal air passes through paths provided in heat exchanger 42 (hereafter equivalent to heat exchangers 42a and 42b). Fan 44 changes the flow direction of the internal air passing through heat exchanger 42 to a vertically downward direction. The internal air blown out from outlet 46 that is the second outlet (hereafter equivalent to second outlet 46a and fourth outlet 46b) via duct 47 to a lower part of housing 31 is led into case 32 that is the second case where heat generator 103 is housed. When the internal air passes inside case 32, the internal air takes away heat generated by heat generator 103. The internal air absorbing the heat is drawn into heat-exchanging device 33 from case 32 via inlet 48 that is the second inlet (hereafter equivalent to second inlet 48a and fourth inlet 48b).
As described above, heat generator casing 30 in the second exemplary embodiment has a structure described below. Heat-exchanging devices 33a and 33b establish passages 41a, 41b, 45a, and 45b in two directions, i.e. horizontal and vertical directions. These heat-exchanging devices 33a and 33b are disposed on case 32 housing the heat generator.
In heat generator casing 30 as configured above, heat generated by heat generator 103, such as a transmitter or receiver, increases the temperature of air inside case 32. This warmed air is drawn into heat-exchanging device 33 through inlet 48 by fan 44. On the other hand, fans 38a and 38b draw in external air, which is cold air outside housing 31, to heat-exchanging devices 33a and 33b through openings 36a and 36b and inlets 39a and 39b. Heat exchangers 42a and 42b installed in heat-exchanging devices 33a and 33b are configured by stacking up heat exchanger plates on which paths for passing air are provided. These heat exchangers 42a and 42b lead in air with temperature difference from two directions, so as to exchange heat between these streams of air. After exchanging the heat by drawing in the internal air and external air to these heat exchangers 42a and 42b, cooled internal air is blown out from outlet 46 into case 32 via duct 47. On the other hand, the external air warmed by heat exchange is blown out from outlets 40a and 40b to outside heat generator casing 30 via opening 37.
As described above, heat-exchanging device 33 in the first exemplary embodiment can reduce the installation area. Since the installation area is small, this heat-exchanging device 33 enables placement of two fans 39a and 38b facing each other on case 32. If centrifugal air blowers are used for fans 38a and 38b, external air is drawn in at a high flow rate from the entire paths of heat exchangers 42a and 42b configuring passages 41a and 41b to fans 38a and 38b. If the external air is drawn in at a high flow rate by fans 38a and 38b, the heat exchange efficiency of heat-exchanging devices 33a and 33b improves. In the same way, if two fans 44a and 44b are used, the internal air vertically circulating in housing 31 also flows fast. The fast flow of the internal air enables removal of more heat generated from the heat generator. Cooling performance of the heat generator thus improves.
As a result, heat generator casing 30 in the second exemplary embodiment can reduce its installation area.
A heat generator casing in the third exemplary embodiment of the present invention is described with reference to
In heat generator casing 50, inner side face 52a that is the fourth side wall, inner side face 52b that is the six side wall, and inner rear face 53 that is the fifth wall are provided inside housing 51 configured with side face 34a that is the first wall, side face 34b that is the third wall, and rear face 35 that is the second wall. As shown in the drawings, opening 36a that is the first opening and opening 36b that is the third opening for drawing in external air are created near the center of side faces 34a and 34b. On inner side face 52a, opening 54a that is the fourth opening is provided at a position facing inlet 39a that is the first inlet of heat-exchanging device 33a. On inner side face 52b, opening 54b that is the sixth opening is created at a position facing inlet 39a that is the third inlet of heat-exchanging device 33b. Opening 36 and opening 54a, and opening 36b and opening 54b are created such that their open areas do not overlap.
Similarly, opening 37 that is the second opening for blowing out external air is provided near the center of rear face 35. On inner rear face 53, opening 55 that is the fifth opening is created at a position facing outlet 40a that is the first outlet of heat-exchanging device 33a and outlet 40b that is the third outlet of heat-exchanging device 33b. Opening 37 and opening 55 are created such that their open areas do not overlap.
As shown in
In the above structure, passage 58a that is the first passage and passage 58b that is the third passage are established through the following routes by driving fans 38a and 38b. External air drawn in from openings 36a and 36b passes through paths 56a and 56b, and is led to openings 54a and 54b. The external air further passes through openings 54a and 54b and inlets 39a and 39b, and is drawn into heat-exchanging devices 33a and 33b. After the external air exchanges its heat with internal air in heat exchangers 42a and 42b in heat-exchanging devices 33a and 33b, fans 38a and 38b change a flow direction, and the external air is led to outlets 40a and 40b. The external air further passes through opening 55 and path 57, and is blown out through opening 37 to outside housing 51.
This heat generator casing 50 achieves the following effect. Passages 58a and 58b are bent only once in heat-exchanging devices 33a and 33b in the third exemplary embodiment. By reducing the number of bends in heat-exchanging devices 33a and 33b, pressure losses caused by bending of passages 58a and 58b can be suppressed. Since pressure losses are suppressed in heat-exchanging devices 33a and 33b, a predetermined cooling performance of heat generator casing 50 can be secured, even if a pressure loss occurs by providing openings 36a and 54a and openings 36b and 54b at different heights.
Accordingly, openings 54a, 54b, and 55 facing heat-exchanging devices 33a and 33b can be created at positions higher than those of openings 36a, 36b, and 37 that are directly open to outside housing 51. Therefore, even if heat generator casing 50 is installed outside, rainwater blowing in from openings 36a, 36b, and 37 is not drawn into heat-exchanging devices 33a and 33b. The cooling performance of heat generator housing 50 will thus last long.
Next is described passage 59 that is the fourth passage (hereafter equivalent to passage 59a that is the second passage and passage 59b that is the fourth passage) vertically formed inside housing 51 of heat generator casing 50.
As shown in
In addition, as shown in
As shown in
As shown in
As a result, the side wall can be thinned, compared with a conventional heat generator casing in which the heat-exchanging device is installed on the side wall, such as a door. A heat generator casing with small installation area and a predetermined cooling performance can be achieved.
The second fluid in housing 51 circulates between inlet 48 and outlet 46 without causing short-circuit by installing heat-exchanging devices 33a and 33b at an upper part in housing 51. As a result, an installation area of heat generator casing 50 can be reduced. Still more, heat generator casing 50 achieves a predetermined freezing performance.
Furthermore, housing 51 has door 64 where duct 60 is provided. As a result, duct 60 is removed by opening door 64 at checking inside heat generator casing 50. Accordingly, inside the casing can be checked efficiently.
A heat generator casing in the fourth exemplary embodiment of the present invention is described with reference to
As shown in
As described in the first to third exemplary embodiments, outlet 46 that is the second outlet is provided to the side of front face 43 of housing 51, and inlet 48 that is the second inlet is provided to the side of rear face 35 of housing 51 in heat-exchanging device 33. Internal air blown out from outlet 46 is drawn into case 32 from a wall to the side of outlet 46 of case 2 via duct 60. The internal air drawn into case 32 rises along a wall to the side of inlet 48 of case 2, and is drawn into inlet 48 of heat-exchanging device 33 from outlet 70 that is the seventh outlet provided on case top 74, which is the top face of the second case. Accordingly, passages 45d and 45e that vertically circulate in housing 51 are formed by driving fan 44.
Guide 71 that is the first guide is provided on case bottom 73, which is the bottom face of the first case. Guide 71 slides on guide 72, which is described later, when case 2 is installed on case 32.
Outlet 70 is provided on case top 74 to circulate internal air from case 32 to inlet 48 of heat-exchanging device 33. As described in the first to third exemplary embodiments, passages 45d and 45e, which are circulating internal air streams, flow downward at the side of front face 43 of housing 51, and flows upward at the side of rear face 35 of housing 51. Accordingly, outlet 70 of case 32 is provided on case top 74 at the side of rear face 35 of housing 51. Guide 72 that is the second guide on which aforementioned guide 71 moves is provided on case top 74. Guide 71 and guide 72 are provided in a direction of helping the movement of case 2. In the fourth exemplary embodiment, this direction is a direction from front face 43 to rear face 35 of housing 51.
As shown in
Guide fitting portion 76 that is the first guide fitting portion is provided on case top 74 between guide 72 and outlet 70. As indicated in the drawing, length L1 of this guide fitting portion 76 is longer than length L2 of guide 71. This structure makes guide 71 and guide fitting portion 76 act as a positioner for attaching case 2 at a predetermined position on case 32.
Procedures for attaching case 2 on cast top 74 are further detailed next. As shown in
As described above, heat-exchanging device 50 is attached by placing guide 71 provided on case bottom 73 on guide 72 provided on case top 74, and moving heat-exchanging device 50 on guide 72. With this structure, heavy heat-exchanging device 50 can be easily attached to case 32. Since the attachment position of case 2 is determined by fitting guide 71 into guide fitting portion 76, case 2 can be fixed without fine adjustment. In addition, since inlet 48 provided on case 2 and outlet 70 provided on case 32 are also fitted at the same time, a man-hour spent for attachment work can be reduced.
As shown in
Catch 82 is provided on guide 71 and guide 72 to engage each other. This structure enables accurate placement of case 2 on case top 74.
The heat generator casing is further described with reference to
As shown in
As shown in
With the above structures, case 2 is placed on case top 74 in a state that the side of inlet 48 is tilted downward. As a result, attachment pressure of outlet 70 and inlet 48 increases by its own weight of case 2. Air-tightness also improves.
This attachment method facilitates attachment on case 32 even if heat-exchanging device 33 is heavy.
As described above, the heat-exchanging device in the exemplary embodiment of the present invention is used in a heat generator casing. Two flows, i.e., the first fluid passing inside and outside the heat generator casing and the second flow circulating inside the heat generator casing, are formed. The first fluid drawn in from the first inlet passes through the heat exchanger, and then the first air blower blows out this first fluid from the first outlet that is horizontally disposed.
The second fluid drawn in from the second inlet passes through the heat exchanger, and then the second air blower blows out this second fluid from the second outlet that is vertically disposed.
If the first air blower and the second air blower form approximately orthogonal flows of a horizontal flow of the first fluid and a vertical flow of the second fluid, the same effects as those described in the exemplary embodiments of the present invention can be achieved.
The second fluid carries heat generated inside the heat generator casing to the heat exchanger. The heat of the second fluid is released to the first fluid in the heat exchanger, and then the second fluid circulates inside the heat generator casing. The first fluid absorbing the heat in the heat exchanger is blown out of the heat generator casing. Accordingly, the heat generated in the heat generator casing is released outside the heat generator casing.
The first fluid drawn in by the first air blower via the heat exchanger is blown out from the first outlet. The second fluid that exchanges the heat with the first fluid via this heat exchanger is drawn into the heat exchanger by the second air blower. The second air blower then blows out the second fluid that has exchanged the heat in the heat exchanger from the second outlet. With this structure, fluids blown out from the first outlet and the second outlet are blown out far away. As a result, occurrence of short-circuiting is prevented, improving cooling performance. In particular, since the second fluid vertically circulates, the heat-exchanging device is not necessarily installed on a door, as in the prior art. The heat-exchanging device can be placed on an upper part in the heat generator casing. Accordingly, an installation area of the heat generator casing can be reduced. In addition, predetermined cooling performance can be achieved.
The heat-exchanging device and the heat generator casing of the present invention is effectively applicable to base stations of communications equipment installed in places with restricted installation area, such as a rooftop of city building, and cooling devices in other pieces of equipment installed outside.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008-030262 | Feb 2008 | JP | national |
| 2008-030263 | Feb 2008 | JP | national |
| 2008-091135 | Mar 2008 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2009/000437 | 2/5/2009 | WO | 00 | 8/3/2010 |
