Heat dissipation structure and camera

Abstract

To efficiently transfer heat, which is generated in each of at least two circuit boards, to a housing.SOLUTION: A camera 10 comprises substrates 31-37, which are arrayed so as to be parallel and overlap with each other in a thickness direction, and a housing 40 in which circuit boards are stored. The camera 10 comprises a GigE processing substrate 34 and a power supply substrate 35 at the rear side thereof. The housing 40 includes a housing member 41 including an opening, which is opened backward, and a housing member 42 which is disposed at a rear side of the housing member 41 and includes an opening which is opened forward. The opening of the housing member 41 includes, at a rear side, fixing surfaces 41A and 41B in contact with a principal surface, which is directed forward, of the substrate 34 and the opening of the housing member 42 includes fixing surfaces 42C and 42D directed forward and being in contact with a principal surface, which is directed backward, of the substrate 35.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a heat dissipation structure for dissipating heat generated in a circuit board. [Background technology]

[0002] Patent Document 1 discloses a heat dissipation structure in which a circuit board is sandwiched between housing members and heat generated on the circuit board is dissipated by radiating it through the housing members. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2016-009558 Summary of the Invention [Problem to be solved by the invention]

[0004] The device disclosed in Patent Document 1 has one circuit board, but in recent years, devices equipped with multiple circuit boards have also been manufactured. In such devices, heat may be generated in, for example, two circuit boards. Here, the technology disclosed in Patent Document 1 cannot be applied to two circuit boards because one circuit board is sandwiched between housing members.

[0005] An object of the present invention is to efficiently transfer heat generated in each of at least two circuit boards to a housing. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the heat dissipation structure of the present invention comprises a plurality of circuit boards arranged parallel to and overlapping each other along a thickness direction, and a housing that houses the plurality of circuit boards, wherein the plurality of circuit boards comprise a first circuit board that generates heat during operation, and a second circuit board that generates heat during operation and is arranged on a first direction side of the thickness direction relative to the first circuit board, wherein the housing comprises a first housing member having a first opening that opens in the first direction, and a second housing member that is arranged on the first direction side of the first housing member and has a second opening that opens in a second direction opposite to the first direction, wherein the first opening faces the first direction and has a first surface that faces the first direction and is in contact with a main surface of the first circuit board that faces the second direction, and the second opening faces the second direction and has a second surface that faces the second direction and is in contact with a main surface of the second circuit board that faces the first direction.

[0007] A camera according to the present invention includes the above-described heat dissipation structure. Effect of the Invention

[0008] According to the present invention, the heat generated in each of the at least two circuit boards is efficiently transferred to the housing. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an exploded perspective view of a camera according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of a part of the camera according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a perspective view of a portion of the camera of FIG. [Figure 4] FIG. 4 is a perspective view of a portion of the camera of FIG. [Diagram 5] FIG. 5 is a side view of a portion of the camera of FIG. [Figure 6] FIG. 6 is an exploded perspective view of a camera according to a second embodiment of the present invention. [Figure 7] FIG. 7 is an exploded perspective view of a camera according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] (First embodiment) 1 to 4, a camera 10 according to this embodiment is configured as a microbolometer type thermography camera. The camera 10 includes a lens unit 20, a substrate group 30, and a housing 40.

[0012] The lens unit 20 includes one or more lenses and a case for housing the lenses. The lens unit 20 is attached to the front end of the housing 40.

[0013] The board group 30 includes a sensor board 31, an analog board 32, a camera board 33, a GigE (Gigabit Ethernet) processing board 34, a power supply board 35, a PoE (Power of Ethernet) board 36, and a connector board 37. The boards 31 to 37 are circuit boards including a plate-shaped printed board and various electronic components mounted on the printed board, and are arranged parallel to and overlapping with each other along the front-rear direction, which is the thickness direction of the boards.

[0014] Among the boards 31 to 37, boards adjacent to each other in the front-to-rear direction are connected to each other by connectors. For example, the sensor board 31 and the analog board 32 behind it are connected to each other by a connector. The connector is used for transmitting and receiving data and for supplying power. The boards may be connected to each other via cables or the like.

[0015] An image sensor 31P facing the lens unit 20 is mounted on the sensor board 31. The image sensor 31P is a microbolometer type infrared image sensor. The sensor board 31 outputs analog data of an infrared image captured by the image sensor 31P via the lens unit 20 to the analog board 32.

[0016] The analog board 32 performs analog processing on the analog data from the sensor board 31. The analog processing includes amplification of the electrical signal, etc. The analog board 32 outputs the analog data after analog processing to the camera board 33 via wiring. The camera board 33 converts the analog data from the analog board 32 into digital image data, and outputs the image data obtained by the conversion to the GigE processing board 34.

[0017] The GigE processing board 34 processes the image data from the camera board 33 and converts it into image data that complies with the GigE standard. The GigE processing board 34 is equipped with an FPGA (Field-Programmable Gate Array) 34P (FIG. 5) that performs the image processing. The image data is output to the outside of the camera 10 via the power supply board 35, the PoE board 36, the connector board 37, and the wiring that connects the boards.

[0018] The connector board 37 includes a connector 37P that is connected to an external Ethernet by wire. Power supplied from the Ethernet via the connector 37P is received by the PoE board 36, converted to a predetermined voltage by the power supply board 35, and supplied to the boards 31 to 33. The power supply board 35 also includes a PHY device 35P (FIG. 5) that converts between analog data on the connector board 37 side and digital data on the GigE processing board 34 side.

[0019] The housing 40 comprises a box-shaped housing member 41 (lens mount) that is open at the rear, a box-shaped housing member 42 (connector mount) that is open at the front, and a plate-shaped member 43 that is screwed to the side surfaces of the housing members 41 and 42 and covers the side surfaces.

[0020] The substrates 31 to 33 are housed in the housing member 41. The substrates 31 to 33 are fixed to each other at intervals by screws with spacers or the like. The substrates 31 to 33 fixed to each other are screwed inside the housing member 41.

[0021] The housing member 41 is provided at the opening, facing rearward perpendicular to the front-rear direction, and has belt-shaped fixing surfaces 41A and 41B extending in the up-down direction. The left and right sides of the camera board 33 extending in the up-down direction are screwed to the fixing surfaces 41A and 41B. As a result, the two belt-shaped parts 33A and 33B constituting the left and right sides, respectively, of the main surface (more specifically, the main surface of the board body; hereinafter the same applies to the main surface) facing forward of the camera board 33 are in surface contact with the fixing surfaces 41A and 41B.

[0022] The housing member 41 is provided at the opening with belt-shaped fixing surfaces 41C and 41D that face rearward perpendicular to the front-rear direction and extend in the left-right direction. The upper and lower sides of the GigE processing board 34 that extend in the left-right direction are screwed to the fixing surfaces 41C and 41D. As a result, the two belt-shaped parts 34A and 34B that respectively constitute the upper and lower sides of the main surface of the GigE processing board 34 that faces forward are in surface contact with the fixing surfaces 41A and 41B, respectively.

[0023] The fixing surfaces 41C and 41D are located rearward of the fixing surfaces 41A and 41B. In addition, the outer shapes of the substrates 33 and 34 when viewed from the front-rear direction are made different from each other, and the parts that do not overlap each other are in surface contact with the fixing surfaces 41A and 41B, and 41C and 41D, respectively. This allows the main surfaces of the substrates 33 and 34, which are arranged to overlap in the front-rear direction, to be in surface contact with the housing member 41.

[0024] The housing member 42 houses the boards 36 and 37. The connector board 37 is screwed inside the housing member 42. The housing member 42 is provided at its opening with belt-shaped fixing surfaces 42A and 42B that face forward perpendicular to the front-rear direction and extend in the up-down direction. The belt-shaped right and left sides of the PoE board 36 that extend in the up-down direction are screwed to the fixing surfaces 42A and 42B, respectively. As a result, the two belt-shaped parts 36A and 36B that respectively constitute the left and right sides of the main surface of the PoE board 36 facing rearward are in surface contact with the fixing surfaces 42A and 42B, respectively.

[0025] The housing member 42 is provided at the opening with band-shaped fixing surfaces 42C and 42D that face forward perpendicular to the front-rear direction and extend in the left-right direction. The band-shaped upper and lower edges of the power supply board 35 that extend in the left-right direction are screwed to the fixing surfaces 42C and 42D. As a result, the two band-shaped portions 35A and 35B that respectively constitute the upper and lower edges of the main surface of the power supply board 35 facing rearward are in surface contact with the fixing surfaces 42C and 42D.

[0026] The fixing surfaces 42C and 42D are located forward of the fixing surfaces 42A and 42B. In addition, the outer shapes of the substrates 35 and 36 when viewed from the front-rear direction are made different, and the parts that do not overlap each other are in surface contact with the fixing surfaces 42A and 42B, 42C and 42D, respectively. This allows the main surfaces of the substrates 35 and 36, which are arranged to overlap in the front-rear direction, to be in surface contact with the housing member 42.

[0027] The plate-like member 43 has heat dissipation fins, which are projections and recesses for heat dissipation, and efficiently dissipates heat from the housing members 41 and 42.

[0028] In this embodiment, since the image sensor 31P is a microbolometer type infrared image sensor, heat generation is suppressed, but if it is affected by heat from other boards, a temperature gradient occurs in the image sensor 31P, and the temperature measurement accuracy decreases. In this embodiment, in particular, the FPGA 34P of the GigE processing board 34 and the PHY device 35P of the power supply board 35 generate heat during operation. In this embodiment, the strip parts 34A and 34B of the GigE processing board 34 are in surface contact with the fixed surfaces 41C and 41D of the housing member 41, so that the heat generated in the FPGA 34A is efficiently transferred to the housing member 41 through the GigE processing board 34 (see arrow R1 in FIG. 5). Furthermore, the strip parts 35A and 35B of the power supply board 35 are in surface contact with the fixed surfaces 42C and 42D of the housing member 42, so that the heat generated in the PHY device 35P is efficiently transferred to the housing member 42 through the power supply board 35 (see arrow R2 in FIG. 5). With this configuration, the heat generated in the two boards 34 and 35 can be efficiently transferred to the housing 40. The heat transferred to the housing 40 is dissipated from the plate-like member 43. As a result, the heat generated in the FPGA 34A of the GigE processing board 34 and the PHY device 35P of the power supply board 35 is less likely to be transferred to the image sensor 31P, reducing the adverse effects of heat. Furthermore, since the heat is efficiently transferred to the housing 40, it is no longer necessary to increase the size of the camera 10 to increase the surface area for heat dissipation or to provide a cooling mechanism such as a fan inside the camera 10, thereby realizing a miniaturized camera 10.

[0029] In this embodiment, the camera board 33 and the PoE board 36 also generate heat due to electronic components such as FPGA, but the strip parts 33A and 33B of the camera board 33 are in surface contact with the fixed surfaces 41A and 41B of the housing 41. Furthermore, the strip parts 36A and 36B of the PoE board 36 are in surface contact with the fixed surfaces 42A and 42B of the housing member 42, respectively. Therefore, the heat generated in the boards 33 and 36 can also be efficiently transferred to the housing members 41 and 42, respectively (see arrows R3 and R4 in FIG. 5), and is dissipated effectively like the heat from the boards 34 and 35.

[0030] Furthermore, since the strip portions 33A and 33B, 34A and 34B, 35A and 35B, and 36A and 36B form one side of the substrate, that is, the length of each strip portion is the length from one end of one side to the other end, the contact area between the substrate 33 to 36 and the housing member 41 or 42 can be increased, and heat transfer becomes more effective.

[0031] It is preferable to connect each of the boards 33 to 36 to the other boards only with inter-board connectors, which makes it difficult for heat from the boards 33 to 36 to be transferred to the other boards, thereby suppressing the thermal load on other electronic components.

[0032] Second embodiment Camera 110 according to the second embodiment shown in Fig. 6 and Fig. 7 has a different housing structure from camera 10. Accordingly, the shapes of boards 31-37 are also changed. Hereinafter, members having the same functions as those in the first embodiment are given the same reference numerals, and duplicated explanations will be omitted. In camera 110 according to the second embodiment, boards 31-37 are directly fixed to housing member 141 or 142, so that heat from each board 31-37 is less likely to be transmitted to the other boards.

[0033] The housing 140 of the camera 110 is made up of a front housing member 141 and a rear housing member 142. The housing members 141 and 142 are provided with heat dissipation fins.

[0034] The housing member 141 has a plurality of fixing surfaces 141A to 141L that are perpendicular to the front-rear direction and face rearward.

[0035] Fixed surfaces 141A to 141D (however, fixed surfaces 141B to 141D are not shown) are provided at the four corners inside housing member 141. Sensor board 31 is screwed to fixed surfaces 141A to 141D. Fixed surfaces 141E to 141H (however, fixed surfaces 141G to 141H are not shown) are provided at the four corners outside fixed surfaces 141A to 141D inside housing member 141. Fixed surfaces 141E to 141H are located rearward of fixed surfaces 141A to 141D. Analog board 32 is screwed to fixed surfaces 141E to 141H.

[0036] The fixed surfaces 141I and 141J (however, the fixed surface 141I is not shown) are strip-shaped and extend in the up-down direction. When viewed from the front-rear direction, the fixed surface 141I is disposed between the fixed surfaces 141E and 141F, and the fixed surface 141J is disposed between the fixed surfaces 141G and 141H. The fixed surfaces 141I and 141J are disposed rearward of the fixed surfaces 141E to 141H. The fixed surfaces 141I and 141J correspond to the fixed surfaces 41A and 41B, and the camera board 33 is screwed to the fixed surfaces 141I and 141J.

[0037] The fixing surfaces 141K and 141L are provided behind the fixing surfaces 141I and 141J and at an opening of the housing member 141. The fixing surfaces 141K and 141L correspond to the fixing surfaces 41A and 41B, and the GigE processing board 34 is fixed to them with screws.

[0038] In this embodiment, the outer shapes of the boards 31 to 34 as viewed from the front-rear direction are different from each other, and the parts of each of the boards 31 to 34 that do not overlap with the other boards are fixed to any of the fixing surfaces 141A to 141L. This allows the main surfaces of the boards 31 to 34 arranged to overlap in the front-rear direction to be in surface contact with the housing member 141. Therefore, the heat generated in each of the boards 31 to 34 is efficiently transferred to the housing member 141. Note that in this embodiment, the amount of heat generated during operation of the boards 31 and 32, etc. (especially the maximum amount of heat generated) is lower than the amount of heat generated during operation of the boards 34 and 35. In such a case, it is preferable to make the contact area of ​​each of the boards 31 and 32 with the housing member 141 smaller than the contact area of ​​the boards 34 and 35 with the housing member 141. This makes it difficult for the heat transferred from the boards 34 and 35 to the housing member 141 to be transferred back to the boards 31 and 32.

[0039] The housing member 142 has a plurality of fixing surfaces 142A-142F that are perpendicular to the front-rear direction and face forward. The fixing surfaces 142A and 142B are provided on the upper and lower sides, respectively, of the bottom surface of the housing member 142, and are strip-shaped extending in the left-right direction, to which the connector board 37 is fixed. The fixing surfaces 142C-142F (however, the fixing surface 142C is not shown) correspond to the fixing surfaces 42A-42D, respectively, and therefore a description of these will be omitted. With this configuration, the heat of each of the boards 35-37 is efficiently transferred to the housing member 142 with which it is in surface contact.

[0040] (Configuration disclosed in this specification) The configurations disclosed in this specification are appended below. Any configuration other than the configurations described in the appendices below may be adopted. The configurations in the appendices below may be combined in any manner. The following parentheses indicate the symbols used in the above embodiment, but the elements to which the parentheses are appended are not limited to the above embodiment.

[0041] (Appendix 1) A plurality of circuit boards arranged in parallel and overlapping relation to each other along a thickness direction; a housing that houses the plurality of circuit boards; The plurality of circuit boards include a first circuit board (34) that generates heat during operation; a second circuit board (35) that generates heat during operation and is disposed on a first direction side in the thickness direction relative to the first circuit board, The housing includes: a first housing member (41 or 141) having a first opening opening in the first direction; a second housing member (42 or 142) disposed on the first direction side of the first housing member and having a second opening portion that opens in a second direction opposite to the first direction; the first opening has a first surface (41A, 41B, 141K, or 141L) facing the first direction and in contact with a main surface of the first circuit board facing the second direction; The second opening has a second surface (42C, 42D, 142E, or 142F) facing the second direction and contacting a main surface of the second circuit board facing the first direction. Heat dissipation structure.

[0042] A specific example of the circuit board is arbitrary. In addition, the use of the heat dissipation structure is not limited to a camera. The shape of the housing is also arbitrary. According to the heat dissipation structure, the first circuit board and the second circuit board are in surface contact with the first housing member and the second housing member, so that heat generated on each board is efficiently transferred to the housing.

[0043] (Appendix 2) the main surface of the first circuit board has a strip-shaped portion (34A or 34B) that constitutes one side of the main surface of the first circuit board and is in contact with the first surface; The main surface of the second circuit board has a strip-shaped portion (35A or 35B) that constitutes one side of the main surface of the second circuit board and is in contact with the second surface. The heat dissipation structure described in Appendix 1.

[0044] According to the above configuration, the contact area between the housing member and the board is increased, and heat transfer becomes more efficient.

[0045] (Appendix 3) The plurality of circuit boards further includes a third circuit board (36) disposed on the first direction side of the second circuit board, the second housing member has a third surface (42A, 42B, 142C, or 142D) that is provided on the first direction side of the first surface, faces the second direction, and contacts a main surface of the third circuit board that faces the first direction; 3. The heat dissipation structure according to claim 1 or 2.

[0046] According to the above configuration, heat from each of the first and third circuit boards can be efficiently transferred to one housing member.

[0047] (Appendix 4) The plurality of circuit boards further includes a fourth circuit board (31 or 32) that generates less heat than the first circuit board and the second circuit board, a contact area of ​​the fourth circuit board with the first housing member or the second housing member is smaller than a contact area of ​​the first circuit board with the first housing member and is also smaller than a contact area of ​​the second circuit board with the second housing member; 4. The heat dissipation structure according to any one of claims 1 to 3.

[0048] According to the above configuration, the heat transferred from the first circuit board or the second circuit board to the housing is prevented from being transferred to the fourth circuit board.

[0049] (Appendix 5) A plurality of circuit boards arranged in parallel and overlapping relation to each other along a thickness direction; a housing that houses the plurality of circuit boards; the plurality of circuit boards include a first circuit board (35) and a second circuit board (36) that have different outer shapes when viewed in the thickness direction and generate heat during operation; The housing includes a housing member (42 or 142) having an open end on the first direction side in the thickness direction, The housing member includes a first surface (42A or 142C) and a second surface (42B or 142D) that face the first direction in the thickness direction and are disposed at positions different from each other in the thickness direction, the first surface and the second surface are in contact with a main surface of the first circuit board facing a second direction opposite to the first direction and a main surface of the second circuit board facing the second direction, respectively; Heat dissipation structure.

[0050] According to the above configuration, heat can be efficiently transferred from each of the first circuit board and the second circuit board to the housing.

[0051] (Appendix 6) the main surface of the first circuit board has a strip-shaped portion (35A or 35B) that constitutes one side of the main surface of the first circuit board and is in contact with the first surface; The main surface of the second circuit board has a strip-shaped portion (36A or 36B) that constitutes one side of the main surface of the second circuit board and is in contact with the second surface. The heat dissipation structure described in Appendix 5.

[0052] According to the above-mentioned configuration, the contact area between the housing member and the main surface of the board is increased, and heat transfer becomes more efficient.

[0053] (Appendix 7) A camera equipped with the heat dissipation structure according to any one of appendix 1 to 6.

[0054] (Scope of the present invention) Although the present invention has been described above with reference to the embodiments and modifications, the present invention is not limited to the above embodiments and modifications. For example, the present invention includes various modifications to the above embodiments and modifications that can be understood by a person skilled in the art within the scope of the technical concept of the present invention. For example, the method of fixing the circuit board to the housing member may be a method using an adhesive. Also, the fixing surface of the housing member may be a contact surface that only contacts the circuit board. In this case, the circuit board is fixed to the housing member at a location different from the fixing surface. A CPU or ASIC may be adopted instead of the FPGA. The configurations listed in the above embodiments and modifications can be appropriately combined within a range without contradiction. Also, omission of each configuration is optional. [Explanation of symbols]

[0055] 10...camera, 20...lens unit, 30...group of boards, 31...sensor board, 31P...image sensor, 32...analog board, 33...camera board, 33A, 33B...strip, 34...GigE processing board, 34A, 34B...strip, 34P...FPGA, 35...power supply board, 35A, 35B...strip, 35P...PHY device, 36...PoE board, 36A, 36B...strip, 37...connector board, 37P...connector, 40...housing, 41, 42...housing parts, 41A to 41D, 42A to 42D...fixing surface, 43...plate-shaped member, 110...camera, 140...housing, 141, 142...housing parts, 141A to 141L, 142A to 142F...fixing surface, R1 to R4...arrows (direction of heat transfer).

Claims

1. A plurality of circuit boards arranged in parallel and overlapping relation to each other along a thickness direction; a housing that houses the plurality of circuit boards; The plurality of circuit boards include a first circuit board that generates heat during operation; a second circuit board that generates heat during operation and is disposed closer to a first direction in the thickness direction than the first circuit board, The housing includes: a first housing member having a first opening portion that opens in the first direction; a second housing member disposed on the first direction side of the first housing member and having a second opening portion that opens in a second direction opposite to the first direction; the first opening has a first surface facing the first direction and in contact with a main surface of the first circuit board facing the second direction; the second opening has a second surface facing the second direction and in contact with a main surface of the second circuit board facing the first direction; Heat dissipation structure.

2. the main surface of the first circuit board has a band-shaped portion that constitutes one side of the main surface of the first circuit board and is in contact with the first surface, the main surface of the second circuit board has a strip-shaped portion that constitutes one side of the main surface of the second circuit board and is in contact with the second surface; The heat dissipation structure according to claim 1 .

3. the plurality of circuit boards further includes a third circuit board disposed on a side of the second circuit board in the first direction, the second housing member has a third surface that is provided on the first direction side of the first surface, faces the second direction, and is in contact with a main surface of the third circuit board that faces the first direction. The heat dissipation structure according to claim 1 .

4. the plurality of circuit boards further includes a fourth circuit board that generates less heat than the first circuit board and the second circuit board; a contact area of ​​the fourth circuit board with the first housing member or the second housing member is smaller than a contact area of ​​the first circuit board with the first housing member and is also smaller than a contact area of ​​the second circuit board with the second housing member; The heat dissipation structure according to claim 1 .

5. A camera comprising the heat dissipation structure according to any one of claims 1 to 4.

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