JP2017220575A - Electronic component cooling structure and electronic device comprising electronic component cooling structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component cooling structure of which the vibration resistance can be increased and furthermore of which the cooling performance can be improved, and an electronic device comprising the electronic component cooling structure.SOLUTION: A heat sink 6 includes a base part 6a and a plurality of fins 6b. A base part 6a between two adjacent fins 6 is provided with a first slit 7. A relay substrate 10 is provided with a second slit 41. One end 8a and the other end 8c of a child substrate 8 are inserted into the first slit 7 and second slit 41, respectively. A third slit 13a is provided in a first inner surface 61c of the first fin 61a. The second fin 61b has a second inner surface 61d opposed to the first fin 61a, and is provided with a fourth slit 13b on the second inner surface. One end 10a and the other end 10c of the relay substrate 10 are inserted into the third slit 13a and fourth slit 13b, respectively.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electronic component cooling structure and an electronic device including the electronic component cooling structure.

  As a conventional technique, a substrate mounting is provided in which a daughter board is provided on both one side and the other side of the intermediate board, and the extension surface of the daughter board on one side intersects the extension surface of the daughter board on the other side. A structure is disclosed (see Patent Document 1).

JP 2004-63525 A

  In the board mounting structure described in Patent Document 1, one end of the sub board is supported by the intermediate board, but the other end of the sub board is not fixed to the intermediate board. Further, when the length of the daughter board is large, the daughter board cannot be stably supported. Therefore, when a heavy component is mounted on the child board, there is a problem that the board mounting structure is vulnerable to vibration.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an electronic component cooling structure and an electronic component cooling structure capable of improving cooling performance while improving vibration resistance. Is to provide an electronic device.

  An electronic component cooling structure according to the present invention includes at least one or more sub-boards, a relay board, and a heat sink. The relay board supports at least one or more child boards. The heat sink includes a base portion having a surface facing the relay substrate and a plurality of fins provided so as to protrude from the surface toward the relay substrate. A first slit is provided in the base portion between two adjacent fins among the plurality of fins. A second slit is provided in a portion of the relay substrate facing the first slit. One end and the other end of at least one or more sub-boards are inserted into the first slit and the second slit, respectively. The plurality of fins include a first fin, a second fin provided at a distance from the first fin, and a third fin between the first fin and the second fin. In the direction perpendicular to the surface, the lengths of the first fin and the second fin are larger than the length of the third fin. The first fin has a first inner surface facing the second fin. A third slit is provided on the first inner surface. The second fin has a second inner surface facing the first fin. A fourth slit is provided on the second inner surface. One end and the other end of the relay substrate are inserted into the third slit and the fourth slit, respectively.

  According to the cooling structure for an electronic component according to the present invention, one end of the daughter board is inserted into the first slit provided in the base part of the heat sink, and the other slit of the daughter board is provided in the relay board. Has been inserted. Therefore, the child board can be held more stably as compared with the conventional board mounting structure. As a result, the vibration resistance of the electronic component cooling structure can be improved. A child board is disposed between two adjacent fins. Thereby, an air path is formed between the sub board and the fin. By arranging the electronic component in the air passage, the electronic component can be effectively cooled during forced cooling.

It is a front schematic diagram which shows the structure of the electronic device which concerns on Embodiment 1 of this invention. It is a perspective schematic diagram which shows the structure of the heat sink which concerns on Embodiment 1 of this invention. It is a cross-sectional schematic diagram which shows the structure of the cooling structure of the electronic component which concerns on Embodiment 1 of this invention. It is a perspective schematic diagram which shows the state in which the electronic component was mounted in the sub-substrate in Embodiment 1 of this invention. It is a front schematic diagram which shows the structure of the electronic device which concerns on Embodiment 2 of this invention. It is a perspective schematic diagram which shows the structure of the heat sink which concerns on Embodiment 2 of this invention. It is a cross-sectional schematic diagram which shows the structure of the cooling structure of the electronic component which concerns on Embodiment 2 of this invention. In Embodiment 2 of this invention, it is a perspective schematic diagram which shows the state by which the electronic component was mounted in the sub board | substrate. It is a front schematic diagram which shows the structure of the electronic device which concerns on Embodiment 3 of this invention. It is a perspective schematic diagram which shows the structure of the heat sink which concerns on Embodiment 3 of this invention. It is a cross-sectional schematic diagram which shows the structure of the cooling structure of the electronic component which concerns on Embodiment 3 of this invention. In Embodiment 3 of this invention, it is a perspective schematic diagram which shows the state by which the electronic component was mounted in the sub board | substrate. It is a plane schematic diagram which shows the structure of the relay board | substrate and subsidiary board | substrate which the cooling structure of the electronic component which concerns on Embodiment 4 of this invention contains. It is a front schematic diagram which shows the structure of the relay board | substrate and sub-board | substrate which the cooling structure of the electronic component which concerns on Embodiment 4 of this invention contains. It is a block diagram which shows the inverter circuit structure mentioned as an example to which Embodiment 1 and Embodiment 2 of this invention are applied. It is a block diagram which shows the circuit structure of the inverter circuit mentioned as an example to which Embodiment 3 of this invention is applied.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

(Embodiment 1)
Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a schematic front view illustrating the configuration of the electronic device according to the first embodiment. FIG. 2 is a schematic perspective view showing the configuration of the heat sink used in FIG. FIG. 3 is a schematic cross-sectional view illustrating a configuration of a cooling structure including a heat sink, a relay substrate, and a slave substrate. FIG. 4 is a schematic perspective view showing a state in which the electronic component is mounted on the sub board. Hereinafter, a general-purpose inverter to which the cooling structure shown in FIG. 3 is applied will be described as an example.

  FIG. 15 is a block diagram showing a circuit configuration of the general-purpose inverter 52. The general-purpose inverter 52 mainly includes an external power source 27, a rectifier circuit 28, a relay 2, a regenerative resistor 9, a brake semiconductor element 29, a main circuit capacitor 1, an inverter circuit 30, and an induction motor 31. doing. The external power supply 27 is a power supply source for the general-purpose inverter 52. The rectifier circuit 28 includes an AC input unit 28a and a DC output unit 28b. The AC input unit 28 a is connected to the external power supply 27. One end of the relay 2 is connected to the anode part of the DC output part 28b. The other end of the relay 2 is connected to one end of the regenerative resistor 9, one end of the main circuit capacitor 1, and the input unit 30 a of the inverter circuit 30. One end of a brake semiconductor element 29 is connected to the other end of the regenerative resistor 9. The other end of the brake semiconductor element 29 is connected to the cathode portion of the DC output portion 28 b of the rectifier circuit 28, the other end of the main circuit capacitor 1, and the input portion 30 a of the inverter circuit 30. An induction motor 31 is connected to the output unit 30 b of the inverter circuit 30. In FIG. 15, a single-phase AC input induction motor is illustrated as an example, but a configuration using a three-phase AC input induction motor may be used.

  In the circuit configuration of the general-purpose inverter 52, the AC voltage from the external power supply 27 is rectified to a DC voltage via the rectifier circuit 28 and smoothed by the main circuit capacitor 1. The smoothed DC voltage is converted into an AC voltage having an arbitrary frequency component by the inverter circuit 30 and drives the induction motor 31. The inverter circuit 30 includes a semiconductor element such as an insulated gate bipolar transistor (IGBT) or a field effect transistor (FET), and a free-wheeling diode. When the induction motor 31 is braked, the back electromotive force generated in the induction motor 31 charges the main circuit capacitor 1 via the freewheeling diode disposed inside the inverter circuit 30. When the induction motor 31 is suddenly braked, a large back electromotive force is generated, and the main circuit capacitor 1 is charged to a voltage exceeding the rated voltage of the main circuit capacitor 1 or the withstand voltage of the IGBT constituting the inverter circuit 30. there is a possibility. Therefore, the generation of excessive back electromotive force is normally suppressed by gradually decreasing the frequency of the inverter circuit 30. As a means for realizing rapid braking of the induction motor 31, there is a method of using a series circuit of the brake resistor 9 and the brake semiconductor element 29 connected in parallel to the main circuit capacitor 1. When the induction motor 31 is suddenly braked, the brake semiconductor element 29 is turned on to forcibly discharge the main circuit capacitor 1 to be charged by the counter electromotive force. By this operation, the induction motor 31 can be suddenly braked without exceeding the rating of the electronic components constituting the inverter.

Next, the configuration of the electronic device 50 according to the first embodiment will be described.
As shown in FIG. 1, the electronic device 50 according to the first embodiment includes a main circuit capacitor 1, a relay 2, a first connector 3, a second connector 11, a main circuit board 4, and a module 5. The brake resistor 9, the terminal block 14, the fastening member 15, and the cooling structure 51 are mainly included. The cooling structure 51 includes a heat sink 6, at least one or more child boards 8, and a relay board 10. That is, the electronic device 50 includes the cooling structure 51 and at least one electronic component such as the brake resistor 9. At least one or more electronic components are mounted on at least one or more child boards 8. On the upper surface of the main circuit board 4, a main circuit capacitor 1, a relay 2, a first connector 3, a drive circuit (not shown) for an inverter circuit 30 (see FIG. 15), and a power circuit (not shown) Etc. are implemented. On the lower surface of the main circuit board 4, the module 5 on which the inverter circuit 30, the rectifier circuit 28, and the brake semiconductor element 29 are mounted is mounted. A heat sink 6 for heat dissipation shown in FIG. 2 is attached to the lower surface of the module 5.

Next, the configuration of the heat sink 6 according to Embodiment 1 will be described.
As shown in FIGS. 2 and 3, the heat sink 6 includes a base portion 6a and a plurality of fins 6b. The base portion 6a has a plate shape, for example. The base portion 6a has a surface 6c facing the relay substrate 10 and a back surface 6d opposite to the surface 6c. The back surface 6d extends along a first direction D1 and a second direction D2 perpendicular to the first direction D1. The longitudinal direction of the back surface 6d is, for example, the first direction D1. The plurality of fins 6 b are provided so as to protrude from the surface 6 c of the base portion 6 a toward the relay substrate 10. The plurality of fins 6b are provided so as to extend in a direction substantially perpendicular to the surface 6c. Each of the plurality of fins 6b is provided substantially in parallel with a predetermined interval. A first slit 7 is provided in a portion of the base portion 6a between two adjacent fins among the plurality of fins 6b. The first slit 7 extends, for example, along the first direction D1. A plurality of the first slits 7 may be provided in the base portion 6a with a certain interval. In FIG. 2, the first slit 7 is provided in the base portion 6 a located between one of the two adjacent fins and the other fin. However, the position where the first slit 7 is provided may be shifted according to the height of the electronic component mounted on one side or both sides of the sub board 8. In other words, the 1st slit 7 may be provided in the one fin side rather than the middle of one fin and the other fin, and may be provided in the other fin side.

  The plurality of fins 6 b include first fins 61 a, second fins 61 b, and third fins 62. The plurality of fins 6b are arranged in the second direction D2, for example. The second fin 61b is provided at a distance from the first fin 61a. The first fin 61a is provided, for example, at one end of the base portion 6a in the second direction D2. For example, the second fin 61b is provided at the other end of the base portion 6a in the second direction D2. The first fin 61a is provided to face the second fin 61b. The third fin 62 is located between the first fin 61a and the second fin 61b. The number of the third fins 62 is one or more. The number of the third fins 62 is not particularly limited. As shown in FIG. 2, the number of the third fins 62 is, for example, four. The longitudinal direction of the plurality of fins 6b is, for example, the first direction D1.

  The outermost fins (first fin 61a and second fin 61b) are longer than the other fins (third fin 62). Specifically, the lengths of the first fins 61 a and the second fins 61 b are larger than the lengths of the third fins 62 in a direction perpendicular to the surface 6 c of the base portion 6 a. The length of the first fin 61a is substantially the same as the length of the second fin 61b. The first fin 61a has a first inner surface 61c facing the second fin 61b. A third slit 13a is provided in the first inner surface 61c. The second fin 61b has a second inner surface 61d that faces the first fin 61a. A fourth slit 13b is provided in the second inner surface 61d. The bottom surface of the third slit 13a faces the bottom surface of the fourth slit 13b. In the direction perpendicular to the surface 6c, the length from the surface 6c to the third slit 13a is substantially the same as the length from the surface 6c to the fourth slit 13b. Each of the third slit 13a and the fourth slit 13b extends, for example, along the first direction D1.

  A module mounting hole 17 for fastening the module 5 to the back surface 6d is provided on the back surface 6d of the base portion 6a. Fastening member attachment holes 16 for fixing the heat sink 6 and the relay substrate 10 are provided in the first fin 61a and the second fin 61b. In FIG. 2, an extrusion type heat sink is described as an example, but a heat sink having a structure in which a plurality of fins 6b are caulked on the base portion 6a may be used. In the above description, the example in which the heat sink 6 is configured by the base portion 6a and the plurality of fins 6b has been described. However, the present invention is not limited to this configuration. The heat sink 6 only needs to include the base portion 6a and the plurality of fins 6b, and may include members other than the base portion 6a and the plurality of fins 6b.

Next, the configuration of the cooling structure according to Embodiment 1 will be described.
As shown in FIG. 3, the electronic component cooling structure 51 mainly includes at least one or more child boards 8, a relay board 10, and a heat sink 6. The relay board 10 supports at least one or more child boards 8. The relay substrate 10 has one end portion 10a, a central portion 10b, and the other end portion 10c. The center part 10b is between the one end part 10a and the other end part 10c. The central portion 10b is sandwiched between one end portion 10a and the other end portion 10c. One end 10a and the other end 10c of the relay substrate 10 are inserted into the third slit 13a and the fourth slit 13b, respectively. In other words, one end portion 10a of the relay substrate 10 is fitted in the third slit 13a. The side wall of the one end 10a may be in contact with the bottom of the third slit 13a. Similarly, the other end portion 10c of the relay substrate 10 is fitted in the fourth slit 13b. The side wall of the other end 10c may be in contact with the bottom of the fourth slit 13b. The central portion 10b is not inserted into each of the third slit 13a and the fourth slit 13b. The central portion 10b is exposed from each of the third slit 13a and the fourth slit 13b.

  A second slit 41 is provided in the portion of the relay substrate 10 facing the first slit 7. The second slit 41 is provided in the central portion 10 b of the relay substrate 10. The relay substrate 10 has a first surface 10d facing the surface 6c of the base portion 6a and a second surface 10e opposite to the first surface 10d. The second slit 41 extends so as to penetrate between the first surface 10d and the second surface 10e. The second slit 41 opens on both the first surface 10d and the second surface 10e of the relay substrate 10. The third fins 62a to 62d may be in contact with the first surface 10d of the relay substrate 10 or may be separated from the first surface 10d.

  At least one or more sub-boards 8 have one end portion 8a, a central portion 8b, and the other end portion 8c. The central portion 8b is between the one end portion 8a and the other end portion 8c. The central portion 8b is sandwiched between one end portion 8a and the other end portion 8c. One end 8a and the other end 8c of at least one or more sub-substrates 8 are inserted into the first slit 7 and the second slit 41, respectively. One end 8 a of the sub board 8 is fitted in the first slit 7. The side wall of the one end 8 a may be in contact with the bottom of the first slit 7. The other end 8 c of the sub board 8 is fitted in the second slit 41. The other end 8c may penetrate the second slit 41 and protrude from the second surface 10e. A part of the other end 8 c may be exposed from the second slit 41. The central portion 8 b is not inserted into each of the first slit 7 and the second slit 41. The central portion 8 b is exposed from each of the first slit 7 and the second slit 41. For example, electronic components such as the brake resistor 9 are mounted on the central portion 8 b of the sub board 8.

  As shown in FIG. 3, one daughter board 8 is disposed between two adjacent fins among the plurality of fins 6b. The sub board 8 is separated from each of the two adjacent fins 6b. In other words, a space in which electronic components are arranged is provided between the sub board 8 and the fins 6b. The sub board 8 is arranged between two adjacent fins so as to divide the space formed by the fins 6b, the base portion 6a, and the relay board 10. In the first embodiment, the number of sub-boards 8 is 5, but the number of sub-boards 8 may be one or more and is not particularly limited.

Next, a state in which the electronic component is mounted on the sub board in the first embodiment will be described.
As shown in FIG. 4, a regenerative brake resistor 9 is mounted on one side or both sides of the sub board 8. As the brake resistor 9, a metal plate resistor may be used, or a surface-mounted resistor, a cement resistor, a jumper, or the like may be used. In addition to the brake resistor, a component that generates heat such as a semiconductor element or a transformer used in the power supply circuit may be mounted.

  The relay board 10 is provided with a second slit 41 (see FIG. 3) into which the sub board 8 is fitted. By soldering the relay substrate 10 and the child substrate 8, the two substrates are energized. Pins (not shown) may be mounted on the end portions of the sub board 8 and the pins may be soldered to the relay board 10, or connectors may be provided on both the sub board 8 and the relay board 10 so May be combined. As shown in FIG. 1, the second connector 11 is mounted on the relay board 10, and the first connector 3 is mounted on the main circuit board 4. The first connector 3 and the second connector 11 are connected by a harness 12. A terminal block 14 for fastening the intermediate board 10 to the connecting member attachment hole 16 is attached to the relay board 10. The terminal block 14 is fastened to the fastening member mounting hole 16 by the fastening member 15. The terminal block 14 is in contact with the second main surface 10d of the relay board 10.

Next, the function and effect of the first embodiment will be described.
In the conventional board mounting structure, one end of the sub board is supported by the intermediate board, but the other end of the sub board is not fixed to the intermediate board. Further, when the length of the daughter board is large, the daughter board cannot be stably supported. Therefore, when a heavy component is mounted on the child board, there is a problem that the board mounting structure is vulnerable to vibration. Further, the conventional board mounting structure has a problem that the entire volume is increased when a heat sink is required because the sub board is provided on both sides of the intermediate board.

  According to the electronic component cooling structure 51 according to the first embodiment, the one end 8 a of the daughter board 8 is inserted into the first slit 7 provided in the base part 6 a of the heat sink 6, and the other end of the daughter board 8. 8 c is inserted into the second slit 41 provided in the relay substrate 10. The relay substrate 10 is inserted into the third slit 13 a and the fourth slit 13 b of the heat sink 6. Therefore, the child board can be held more stably as compared with the conventional board mounting structure. As a result, the vibration resistance of the electronic component cooling structure can be improved.

  The cooling structure 51 has a terminal block 14 for fastening to the fastening member mounting hole 16, and the terminal block 14 is fastened to the fastening member mounting hole 16 by the fastening member 15. Thereby, the vibration resistance of the cooling structure can be further improved.

  Furthermore, according to the electronic component cooling structure 51 according to the first embodiment, the sub board 8 on which the brake resistor 9 is mounted is disposed in the space between two adjacent fins. Since the brake resistor 9 generates heat when the brake semiconductor element is driven, it is necessary to suppress a temperature rise using a cooling means such as a fan. By arranging the sub board 8 between two adjacent fins, an air path is formed between the fin and the sub board 8. Thereby, the brake resistor 9 can be effectively cooled during forced air cooling. Further, without increasing the entire volume of the cooling structure, a heat radiation cooling effect can be obtained within the volume range of the heat sink 6 and the vibration resistance can be improved.

  By forming as many series and parallel circuits of surface mount components as possible so that the brake resistor 9 satisfies the derating with respect to the generated loss, the apparent surface area is increased and the heat dissipation capability is improved. Since the plurality of sub boards 8 are mounted on the relay board 10, the number of sub boards 8 can be increased or decreased according to the capacity of the inverter.

(Embodiment 2)
Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 5 is a schematic front view showing the electronic apparatus according to the second embodiment. FIG. 6 is a schematic perspective view of the heat sink used in FIG. FIG. 7 is a schematic cross-sectional view showing the configuration of the electronic component cooling structure according to the second embodiment. FIG. 8 is a schematic perspective view showing a state in which the electronic component is mounted on the sub board. 5 to 8, the same or corresponding components as those in FIGS. 1 to 4 are denoted by the same reference numerals. Hereinafter, the configuration different from that of the first embodiment will be mainly described.

First, the configuration of the electronic device 50 according to the second embodiment will be described.
As shown in FIG. 5, the electronic device 50 according to the second embodiment includes a main circuit capacitor 1, a relay 2, a first connector 3, a second connector 11, a third connector 20, and a fourth connector. 21, main circuit board 4, module 5, brake resistor 9, second main circuit capacitor 19, heat sink 6, sub board 8, and relay board 10. On the upper surface of the main circuit board 4, a main circuit capacitor 1, a relay 2, a first connector 3, a third connector 20, a drive circuit (not shown) for the inverter circuit 30, and a power circuit (not shown). ) Etc. are implemented. On the lower surface of the main circuit board 4, the module 5 on which the inverter circuit 30, the rectifier circuit 28, and the brake semiconductor element 29 are mounted is mounted. A heat sink 6 for heat dissipation shown in FIG. 6 is attached to the lower surface of the module 5.

Next, the configuration of the heat sink 6 according to Embodiment 2 will be described.
As shown in FIGS. 6 and 7, the heat sink 6 includes a base portion 6a and a plurality of fins 6b. The base portion 6a has a surface 6c facing the relay substrate 10 and a back surface 6d opposite to the surface 6c. The plurality of fins 6 b are provided so as to protrude from the surface 6 c of the base portion 6 a toward the relay substrate 10. In FIG. 5, an extrusion type heat sink is described as an example, but a structure in which a plurality of fins 6b are caulked on the base portion 6a may be employed. A module mounting hole 17 for fastening the module 5 to the back surface 6d is provided on the back surface 6d of the base portion 6a.

  A first slit 7 is provided in a portion of the base portion 6a between two adjacent fins among the plurality of fins 6b. In FIG. 2, the 1st slit 7 is provided in the base part located in the middle of one fin and the other fin of two adjacent fins. However, the position where the first slit 7 is provided may be shifted according to the height of the electronic component mounted on one side or both sides of the sub board 8. In the second embodiment, the interval between the second fin 61b located on the outermost side and the third fin 62c adjacent to the second fin 61b is made wider than the interval between the other fins. In other words, the interval W1 between the second fin 61b and the third fin 62c is the interval W2 between the third fin 62c and the third fin 62b, the interval W3 between the third fin 62b and the third fin 62a, and the third fin 62a. And wider than each of the intervals W4 between the first fins 61a (see FIG. 7). That is, the interval W1 between the second fin 61b and the third fin 62c closest to the second fin 61b is larger than the interval W4 between the first fin 61a and the third fin 62a closest to the first fin 61a. A sixth slit 18 is provided in the portion of the base portion 6a between the second fin 61b and the third fin 62c. In the second direction D2, the distance between the sixth slit 18 and the second fin 61b may be longer than the distance between the sixth slit 18 and the third fin 62c closest to the second fin 61b.

Next, the configuration of the cooling structure according to Embodiment 2 will be described.
As shown in FIG. 7, the cooling structure 51 includes a heat sink 6, a relay substrate 10, and at least one or more child substrates 8. The relay substrate 10 has one end portion 10a, a central portion 10b, and the other end portion 10c. The center part 10b is between the one end part 10a and the other end part 10c. One end 10a and the other end 10c of the relay substrate 10 are inserted into the third slit 13a and the fourth slit 13b, respectively. A second slit 41 is provided in the portion of the relay substrate 10 facing the first slit 7. Similarly, a seventh slit 42 is provided in the portion of the relay substrate 10 facing the sixth slit 18. The second slit 41 and the seventh slit 42 are provided in the central portion 10 b of the relay substrate 10. The third fins 62a to 62d may be in contact with the first surface 10d of the relay substrate 10 or may be separated from the first surface 10d.

  The sub board 8 has one end part 8a, a central part 8b, and the other end part 8c. The central portion 8b is between the one end portion 8a and the other end portion 8c. One end 8a and the other end 8c of the daughter board 8 arranged between the second fin 61b and the third fin 62c are inserted into the sixth slit 18 and the seventh slit 42, respectively. One end 8 a of the sub board 8 is fitted in the sixth slit 18. The other end 8 c of the sub board 8 is fitted in the seventh slit 42. One end 8a and the other end 8c of the remaining child substrate 8 are inserted into the first slit 7 and the second slit 41, respectively. One end 8 a of the remaining sub-board 8 is fitted in the first slit 7. The other end portion 8 c of the remaining child substrate 8 is fitted in the second slit 41.

Next, a state in which the electronic component is mounted on the sub board in the second embodiment will be described.
As shown in FIG. 8, in the space where the fin interval is narrow, the sub board 8 on which the brake resistor 9 for regeneration is mounted on one side or both sides is arranged. The child board 8 on which the second main circuit capacitor 19 is mounted is disposed in a space having a wide fin interval. The relay board 10 is provided with a second slit 41 and a seventh slit 42 into which the sub board 8 is fitted. The relay substrate 10 and the child substrate 8 are soldered to energize the two substrates. Pins (not shown) may be mounted on the end of the sub board 8, and the pins may be soldered to the relay board 10, or connectors may be provided on both the sub board 8 and the relay board 10 to connect the two boards. May be. As shown in FIG. 5, the second connector 11 and the fourth connector 21 are mounted on the relay board 10, and the first connector 3 and the third connector 20 are mounted on the main circuit board 4. . The third connector 20 and the fourth connector 21 are connected by a harness 22. Similarly, the first connector 3 and the second connector 11 are connected by a harness 12. The second main circuit capacitor 19 is connected in parallel to the main circuit capacitor 1 via a harness.

  Referring to FIG. 5 again, the electronic device 50 according to the third embodiment includes an electronic component cooling structure 51, and a brake resistor 9 (a first fin 61a disposed between the first fin 61a and the third fin 62a). Electronic component) and a second main circuit capacitor 19 (second electronic component) disposed between the second fin 61b and the third fin 62c. In the direction from the first fin 61a to the second fin 61b, the height H2 of the brake resistor 9 is lower than the height H1 of the second main circuit capacitor 19. As described above, in the electronic component cooling structure according to the third embodiment, electronic components having different heights can be mounted on the sub board 8.

  In the second embodiment, the sub board 8 on which the second main circuit capacitor 19 is mounted is disposed in the space between the second fin 61b and the third fin 62c of the heat sink 6. The cooling performance of the second main circuit capacitor 19 disposed between the sub board 8 and the second fin 61b is improved by forming the air path between the sub board 8 and the second fin 61b during forced air cooling. In addition, when an electrolytic capacitor is used for the second main circuit capacitor 19, the temperature rise is suppressed by the cooling air during forced air cooling, which is effective in extending the life of the inverter. In addition, by using a second main circuit capacitor 19 having a small diameter and increasing the number of parallel capacitors, the apparent surface area is expanded, and the heat dissipation capability is improved.

  Further, according to the second embodiment, the sub board 8 on which the second main circuit capacitor 19 which is a heavy object is mounted is disposed in the space between the second fin 61b and the third fin 62c of the heat sink 6. . However, the child substrate 8 is mounted on the sixth slit 18 of the heat sink 6 and the seventh slit 42 of the relay substrate 10, and the one end 10 a of the relay substrate 10 and the like are respectively connected to the third slit 13 a and the fourth slit 13 b of the heat sink 6. The end 10c is inserted. Therefore, the second embodiment has improved vibration resistance compared to the conventional board mounting structure.

(Embodiment 3)
Embodiment 3 of the present invention will be described with reference to the drawings. FIG. 9 is a schematic front view showing a cooling structure for an electronic component according to the third embodiment. FIG. 10 is a schematic perspective view of the heat sink used in FIG. FIG. 11 is a schematic cross-sectional view illustrating a configuration of a cooling structure for an electronic component according to the third embodiment. FIG. 12 is a schematic perspective view showing a state in which the electronic component is mounted on the sub board. 9 to 12, the same or corresponding components as those in FIGS. 1 to 8 are denoted by the same reference numerals. Hereinafter, the configuration different from the first embodiment and the second embodiment will be mainly described. As an application example of the electronic component cooling structure of the third embodiment, a general-purpose inverter will be described as an example.

  FIG. 16 is a block diagram showing a circuit configuration of the general-purpose inverter. Components that are the same as or correspond to those in FIG. 15 are denoted by the same reference numerals. When the input voltage of the external power supply 27 is 400 V (AC) or more, the withstand voltage of the electrolytic capacitor may be exceeded in the configuration with one main circuit capacitor 1 (one series) as shown in FIG. Therefore, as shown in FIG. 16, it is common to connect a third main circuit capacitor 25 and a fourth main circuit capacitor 26 in series and provide a balance resistor 32 in parallel with each capacitor. A plurality of third main circuit capacitors 25 and a plurality of fourth main circuit capacitors 26 may be connected in parallel according to the required capacitance value. Further, the number of series may be increased according to the input voltage, for example, four main circuit capacitors are connected in series (4 series).

  In the general-purpose inverter circuit configured as described above, the AC voltage from the external power supply 27 is rectified to a DC voltage via the rectifier circuit 28 and smoothed by the third main circuit capacitor 25 and the fourth main circuit capacitor 26. In the case of two series, a voltage of effective value of input voltage × √2 / 2 is applied to both ends of each capacitor, but it is necessary to secure an insulation distance according to the safety standard applied to the product. Since a large capacitance value is required for the main circuit capacitor, an electrolytic capacitor is generally used. In general, polyvinyl chloride is mainly used for the sleeve of the electrolytic capacitor. However, when insulation is not recognized in safety standards, it is necessary to secure an insulation distance. When a sufficient insulation distance cannot be secured in terms of mounting, the use of polyolefin for the sleeve material satisfies the standard and allows the capacitors to be brought close to each other. However, polyolefin is more expensive than polyvinyl chloride, which increases the cost of the product.

Next, the configuration of the electronic device 50 according to the third embodiment will be described.
As shown in FIG. 9, the electronic device 50 according to the third embodiment includes a main circuit capacitor 1, a relay 2, a first connector 3, a second connector 11, a third connector 20, and a fourth connector. 21, main circuit board 4, module 5, brake resistor 9, third main circuit capacitor 25, fourth main circuit capacitor 26, heat sink 6, child board 8, relay board 10, partition board 24 mainly. On the upper surface of the main circuit board 4, a main circuit capacitor 1, a relay 2, a first connector 3, a third connector 20, a drive circuit (not shown) for the inverter circuit 30, and a power circuit (not shown). ) Etc. are implemented. On the lower surface of the main circuit board 4, the module 5 on which the inverter circuit 30, the rectifier circuit 28, and the brake semiconductor element 29 are mounted is mounted. A heat sink 6 for heat dissipation shown in FIG. 10 is attached to the lower surface of the module 5.

Next, the configuration of the heat sink 6 according to Embodiment 3 will be described.
As shown in FIGS. 10 and 11, the heat sink 6 includes a base portion 6a and a plurality of fins 6b. The base portion 6a has a surface 6c facing the relay substrate 10 and a back surface 6d opposite to the surface 6c. The plurality of fins 6 b are provided so as to protrude from the surface 6 c of the base portion 6 a toward the relay substrate 10. In FIG. 10, an extrusion type heat sink is described as an example, but a structure in which a plurality of fins 6b are caulked on the base portion 6a may be used. A module mounting hole 17 for fastening the module 5 to the back surface 6d is provided on the back surface 6d of the base portion 6a.

  A first slit 7 is provided in a portion of the base portion 6a between two adjacent fins among the plurality of fins 6b. In the third embodiment, the interval between the second fin 61b located on the outermost side and the third fin 62c adjacent to the second fin 61b is made wider than the interval between the other fins. In other words, the interval W1 between the second fin 61b and the third fin 62c is the interval W2 between the third fin 62c and the third fin 62b, the interval W3 between the third fin 62b and the third fin 62a, and the third fin 62a. And wider than each of the distances W4 between the first fins 61a (see FIG. 11). A sixth slit 18 is provided in the portion of the base portion 6a between the second fin 61b and the third fin 62c.

  The second fin 61b has a second inner surface 61d that faces the first fin 61a. The second inner surface 61d is provided with a fourth slit 13b for inserting the relay substrate 10 and a fifth slit 23 different from the fourth slit 13b. The fifth slit 23 is a slit for inserting the partition substrate 24. The fifth slit 23 is provided between the fourth slit 13b and the base portion 6a. The fifth slit 23 extends, for example, in the first direction D1. The fifth slit 23 is substantially parallel to the fourth slit 13b.

Next, the configuration of the cooling structure according to Embodiment 3 will be described.
As shown in FIG. 11, the cooling structure 51 includes a heat sink 6, a relay substrate 10, at least one or more sub-substrates 8, and a partition substrate 24. The partition substrate 24 is supported by at least one or more child substrates. The relay substrate 10 has one end portion 10a, a central portion 10b, and the other end portion 10c. The center part 10b is between the one end part 10a and the other end part 10c. One end 10a and the other end 10c of the relay substrate 10 are inserted into the third slit 13a and the fourth slit 13b, respectively. A second slit 41 is provided in the portion of the relay substrate 10 facing the first slit 7. Similarly, a seventh slit 42 is provided in the portion of the relay substrate 10 facing the sixth slit 18. The second slit 41 and the seventh slit 42 are provided in the central portion 10 b of the relay substrate 10. The third fins 62a to 62d may be in contact with the first surface 10d of the relay substrate 10 or may be separated from the first surface 10d.

  The sub board 8 has one end part 8a, a central part 8b, and the other end part 8c. The central portion 8b is between the one end portion 8a and the other end portion 8c. One end 8a and the other end 8c of the daughter board 8 arranged between the second fin 61b and the third fin 62c are inserted into the sixth slit 18 and the seventh slit 42, respectively. One end 8 a of the sub board 8 is fitted in the sixth slit 18. The other end 8 c of the sub board 8 is fitted in the seventh slit 42. One end 8a and the other end 8c of the remaining child substrate 8 are inserted into the first slit 7 and the second slit 41, respectively. One end 8 a of the remaining sub-board 8 is fitted in the first slit 7. The other end portion 8 c of the remaining child substrate 8 is fitted in the second slit 41. The partition board 24 is mounted on the sub board 8 disposed between the second fin 61b and the third fin 62c closest to the second fin 61b. One end of the partition substrate 24 is inserted into the fifth slit 23 and fixed. The other end of the partition board 24 is fixed to the daughter board 8. A slit hole (not shown) is provided in the portion of the sub-board 8 that faces the fifth slit 23. The slit hole is provided in the central portion 8 b of the sub board 8. The other end of the partition substrate 24 is inserted and fixed in the slit hole.

Next, a state where the electronic component is mounted on the sub board in the third embodiment will be described.
As shown in FIG. 12, in the space where the fin interval is narrow, the sub board 8 on which the brake resistor 9 for regeneration is mounted on one side or both sides is arranged. In the space where the fin interval is wide, the sub board 8 on which the third main circuit capacitor 25, the fourth main circuit capacitor 26, and the partition board 24 are mounted is disposed. The sub board 8 is provided with a slit hole into which the partition board 24 is fitted. The sub-board 8 and the partition board 24 are soldered to energize both boards. A connector may be provided on each of the partition board 24 and the sub board 8 to couple the boards together.

  Referring to FIG. 9 again, the electronic device 50 according to the third embodiment includes an electronic component cooling structure 51, a third main circuit capacitor 25 (first electrolytic capacitor), and a fourth main circuit capacitor 26 (first 2 electric field capacitors). The third main circuit capacitor 25 is mounted on the sub board 8 and has a first potential. The fourth main circuit capacitor 26 is mounted on the daughter board 8 and has a second potential different from the first potential. The fourth main circuit capacitor 26 is separated from the third main circuit capacitor 25 by the partition board 24. In other words, the partition substrate 24 is disposed between the third main circuit capacitor 25 and the fourth main circuit capacitor 26.

  In the third embodiment, a third main circuit capacitor 25 and a fourth main circuit capacitor 26 having different potentials and a partition board 24 are mounted on the sub board 8. By mounting the partition board 24 between the third main circuit capacitor 25 and the fourth main circuit capacitor 26 having different potentials, a creepage distance and a spatial distance are secured, and the capacitors can be mounted close to each other.

  According to the third embodiment, the third main circuit capacitor 25 and the fourth main circuit capacitor 26, which are heavy objects, are mounted in the space between the second fin 61b and the third fin 62c of the heat sink 6. A sub board 8 is arranged. However, one end of the partition board 24 is inserted and fixed in the fifth slit 23 of the heat sink 6, and the other end of the partition board 24 is inserted and fixed in the slit hole of the sub board 8. Therefore, the third embodiment has improved vibration resistance compared to the conventional board mounting structure. Further, the partition substrate 24 becomes an insulator that insulates the third main circuit capacitor 25 and the fourth main circuit capacitor 26. Therefore, the main circuit capacitors can be mounted close to each other without using expensive polyolefin. As a result, it is possible to simultaneously achieve insulation and reduce costs.

(Embodiment 4)
Embodiment 4 of the present invention will be described with reference to the drawings. FIG. 13 is a schematic top view illustrating the configuration of the relay board and the sub board included in the electronic component cooling structure according to the fourth embodiment. FIG. 14 is a schematic front view illustrating the configuration of the relay board and the sub board included in the electronic component cooling structure according to the fourth embodiment. FIG. 14 is a view as seen from the third direction D3 of FIG.

  As shown in FIG. 13, the electronic component cooling structure according to the fourth embodiment mainly includes a relay substrate 10, at least one or more sub-substrates 8, and a heat sink (not shown). At least one or more child boards 8 have a plurality of child boards 8 arranged away from each other. A plurality of sub-boards 8 are mounted on the relay board 10. Electronic components that generate heat are mounted on the plurality of sub-boards 8. Each of the plurality of sub boards 8 is mounted in a corresponding slit (not shown) provided in the relay board 10. The slits are provided in a spiral shape on the relay substrate 10. Specifically, the plurality of sub boards 8 are arranged so as to surround the center O of the relay board 10. Six sets of sub boards 8 are arranged so as to surround the center O as a set of three sub boards 8 parallel to each other. Among the six sets of child boards 8, the six sets of child boards 8 are arranged so that the extending direction of one of the two adjacent child boards 8 intersects the extending direction of the other child board 8. . The surface 10 d of the relay substrate 10 faces the surface 6 c of the base portion 6 a of the heat sink 6. Note that the center O of the relay substrate 10 is a position where, for example, a straight line that passes through the center of gravity of the relay substrate and is perpendicular to the surface 10d intersects the surface 10d.

  As shown in FIG. 13, when viewed from a direction perpendicular to the surface 6c of the base portion 6a (that is, a direction perpendicular to the surface 10d of the relay substrate 10), one side of each of the plurality of sub-substrates 8 The distance L1 between the end 8d and the center O is shorter than the distance L2 between the other end 8e of each of the plurality of sub-substrates 8 and the center O. As shown in FIG. 14, each of the plurality of child boards 8 extends in a direction perpendicular to the surface 10 d of the relay board 10. Each of the plurality of sub-boards 8 may be fitted into the slits so as to penetrate a slit (not shown) provided in the relay board 10. The height of each of the plurality of sub-substrates 8 may be substantially the same.

  Each of the plurality of sub boards 8 mounted on the relay board 10 is disposed between two adjacent fins of the heat sink. A plurality of fins are provided in the base portion of the heat sink, and the plurality of fins are provided in a spiral shape in the base portion. Specifically, the plurality of fins are arranged so as to surround the center of the base portion. Similar to the first embodiment, the sub board 8 is inserted and fixed in a slit provided in the base portion of the heat sink. The relay substrate 10 is fastened to the heat sink by a fastening member.

  According to the fourth embodiment, the sub board 8 mounted on the relay board 10 is disposed between two adjacent fins of the heat sink provided in a spiral shape. Similar to the first embodiment, the sub board 8 is inserted and fixed in the first slit 7 provided on the surface of the base portion. Therefore, in the fourth embodiment, the heat radiation cooling effect by the spiral air flow is obtained within the volume range of the heat sink, and the vibration resistance is improved.

  The embodiment disclosed this time is to be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  1 main circuit capacitor, 2 relay, 3 first connector, 4 main circuit board, 5 module, 6 heat sink, 6a base part, 6b fin, 6c, 10d surface, 6d back surface, 7 first slit, 8 sub board, 8a, 10a one end, 8b, 10b center, 8c, 10c other end, 8d one end, 8e other end, 9 brake resistance (regenerative resistance), 10 relay board, 10d first surface, 10e second surface , 11 Second connector, 12, 22 Harness, 13a Third slit, 13b Fourth slit, 14 Terminal block, 15 Fastening member, 16 Fastening member mounting hole, 17 Module mounting hole, 18 Sixth slit, 19 Second main circuit Capacitor, 20 3rd connector, 21 4th connector, 23 5th slit, 24 Partition board, 25 3rd main circuit component 26, 4th main circuit capacitor, 27 external power supply, 28 rectifier circuit, 28a AC input section, 28b DC output section, 29 brake semiconductor element, 30 inverter circuit, 30a input section, 30b output section, 31 induction motor, 32 Balance resistance, 41 2nd slit, 42 7th slit, 50 electronic device, 51 cooling structure, 52 general-purpose inverter, 61a first fin, 61b second fin, 61c first inner surface, 61d second inner surface, 62, 62a, 62b , 62c, 62d Third fin, D1 first direction, D2 second direction, D3 third direction.

Claims (7)

At least one or more sub-boards;
A relay board that supports the at least one or more child boards;
With a heat sink,
The heat sink includes a base portion having a surface facing the relay substrate, and a plurality of fins provided so as to protrude from the surface toward the relay substrate,
In the portion of the base portion between two adjacent fins among the plurality of fins, a first slit is provided,
A second slit is provided in the portion of the relay substrate facing the first slit,
One end portion and the other end portion of the at least one sub-board are inserted into the first slit and the second slit, respectively.
The plurality of fins include a first fin, a second fin provided at a distance from the first fin, and a third fin between the first fin and the second fin,
In a direction perpendicular to the surface, the length of the first fin and the second fin is greater than the length of the third fin,
The first fin has a first inner surface facing the second fin, and a third slit is provided in the first inner surface,
The second fin has a second inner surface facing the first fin, and the second inner surface is provided with a fourth slit,
An electronic component cooling structure in which one end and the other end of the relay substrate are inserted into the third slit and the fourth slit, respectively.   The electronic component cooling structure according to claim 1, wherein an interval between the second fin and the third fin is larger than an interval between the first fin and the third fin. A partition board supported by the at least one or more sub-boards;
A fifth slit different from the fourth slit is provided on the second inner surface,
One end of the partition board is inserted into the fifth slit,
3. The electronic component cooling structure according to claim 1, wherein the other end of the partition board is fixed to the at least one or more sub-boards. 4. The at least one or more sub-boards have a plurality of sub-boards arranged apart from each other,
The plurality of child boards are arranged so as to surround the center of the relay board,
When viewed from a direction perpendicular to the surface, the distance between one end of each of the plurality of sub-substrates and the center is the distance between the other end of each of the sub-substrates and the center. The cooling structure for an electronic component according to claim 1, wherein the cooling structure is shorter. The electronic component cooling structure according to any one of claims 1 to 4,
An electronic apparatus comprising: at least one or more electronic components mounted on the at least one or more sub-boards. A cooling structure for an electronic component according to claim 2,
A first electronic component disposed between the first fin and the third fin;
A second electronic component disposed between the second fin and the third fin;
An electronic device, wherein a height of the first electronic component is lower than a height of the second electronic component in a direction from the first fin to the second fin. A cooling structure for an electronic component according to claim 3,
A first electrolytic capacitor mounted on the at least one sub-board and having a first potential;
An electronic apparatus comprising: a second electric field capacitor having a second potential different from the first potential and separated from the first electrolytic capacitor by the partition substrate.

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