JP2000252657A - Heat dissipation unit for control apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To absorb and dissipate heat generated from power elements among a plurality of electronic parts efficiently while simplifying the assembling work. SOLUTION: A mother board 60 is secured to a heat dissipation fin 40 using a screw 68 and further secured to the projecting part 75 of a case 70 through the heat dissipation fin 40 using screws 69. Consequently, heat generated from a heat generating electronic part on a ceramic board bonded to the heat dissipation fin 40 can be conducted surely to the case 70 side thence absorbed and dissipated efficiently thus enhancing heat dissipation. Furthermore, workability is enhanced significantly because te assembling work is simplified by screwing the board only from one direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat radiating device for a control device such as an electronic control device in which a substrate on which a plurality of electronic components are mounted is mounted on a motherboard. The present invention relates to a heat radiating device of a control device capable of radiating heat.

[0002]

2. Description of the Related Art Conventionally, as a prior art document related to a heat radiating device for a control device, there is known a document disclosed in Japanese Patent Application Laid-Open No. HEI 8-111575. In this device, a semiconductor chip itself is directly mounted on a metal substrate, so-called bare chip mounting, and positioning pins provided on the substrate are inserted into holes on the motherboard and assembled, and heat from the power elements is radiated. The technique for is shown.

[0003]

By the way, in the above-mentioned device, since the substrate on which a plurality of electronic components are mounted is a metal substrate, the substrate itself has a function of a heat radiating fin (heat sink). There is a limit in the size of the substrate, and there is a problem that a heat capacity sufficient to efficiently absorb and diffuse heat from the power element mounted on the substrate cannot be obtained.

In view of the above, the present invention has been made to solve such a problem, and is a heat radiating device for a control device in which a board on which a plurality of electronic components are mounted is mounted on a motherboard and housed in a housing. It is an object of the present invention to provide a heat radiating device for a control device capable of efficiently absorbing and radiating heat generated from a power element of the electronic component and simplifying an assembling operation.

[0005]

According to the heat radiating device of the control device of the first aspect, the mother board is screwed and fixed to the heat radiating member, and is screwed and fixed to the inner wall portion of the housing with the heat radiating member interposed. Thus, heat from the heat-generating electronic component of the substrate bonded to the heat radiating member can be reliably conducted directly to the housing side to efficiently absorb and radiate heat, thereby improving heat radiation. Further, the assembling work by screwing and fixing is simplified to only from the same direction, and workability is remarkably improved.

According to the heat radiating device of the control device of the second aspect,
The motherboard is screwed and fixed to the heat radiating member from the outside with the lid of the housing, and the heat radiating member is interposed from the outside with the lid of the housing and screwed and fixed to the inner wall portion of the housing together. Thus, the heat from the heat-generating electronic components of the board joined to the heat-dissipating member can be directly and reliably conducted to the housing side and efficiently absorbed and dissipated, thereby improving heat dissipation. In addition, the mother board is screwed and fixed in contact with the cover member of the housing, and the heat from the heat-generating electronic components of the board joined to the heat dissipation member is also conducted to the cover member side of the housing. And heat dissipation is further improved. Then, the assembling work by screwing and fixing is simplified to only from the same direction, and workability is remarkably improved.

According to a third aspect of the present invention, the heat radiating device is configured such that the heat radiating member is in contact with the heat radiating pattern formed on the motherboard. As a result, heat can be efficiently absorbed and dissipated from the heat dissipating member via the motherboard, and heat dissipating properties are improved.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

Embodiment 1 FIG. 1 is a perspective view showing an overall configuration of an electronic control apparatus to which a heat radiating device for a control apparatus according to a first embodiment of the present invention is applied, and FIG. 1
FIG. 2 is a cross-sectional view illustrating a main configuration of the electronic control device taken along line AA.

Referring to FIG. 1, an electronic control unit 1 according to this embodiment
In 00, a plurality of ceramic substrates 10 having high heat dissipation are used as thick film substrates. A drive transistor (power transistor) 21 as a power element having heat generation properties and other electronic components 22 are mounted on the plurality of ceramic substrates 10. The plurality of ceramic substrates 10 are further bonded to a radiating fin 40 formed of an aluminum material or the like via a high-heat-conductivity adhesive, for example, a silicon-based adhesive in order to absorb and radiate heat generated by the driving transistor 21. ing.

Lead terminal 31 from ceramic substrate 10
Are soldered and electrically connected to the motherboard 60. A connector 50 is fixed by screwing near the periphery of one side of the motherboard 60, and lead terminals (not shown) of the connector 50 and other electronic components are also soldered to the motherboard 60 and electrically connected thereto. I have. The motherboard 60 thus configured is housed in a case 70 made of, for example, an aluminum material or the like having high thermal conductivity, as shown in FIGS. 1 and 2. In FIG. 2, the ceramic substrate 10 and the like joined to the radiation fin 40 in FIG. 1 are omitted.

At this time, the projections 41 formed on the left and right sides of the radiation fins 40 come into contact with the projections 75 formed on the inner wall surface of the case 70. Then, as shown in FIG. 2, in the central portion of the motherboard 60, the heat radiation fins 40 to which the plurality of ceramic substrates 10 are joined are screwed and fixed using screws 68. Further, the left and right peripheral portions of the motherboard 60 are screwed and fixed to the protruding portion 75 of the case 70 from the same direction using the screws 69 with the radiation fins 40 interposed therebetween. Thereafter, a cover formed of an aluminum material or the like (not shown) is covered, and the electronic control device 100 is completed by being screwed and fixed.

Further, as shown in FIG.
A heat radiation pattern 65 in which a screw hole 66 is formed is formed on a contact surface of the heat radiation fin 40 with the heat radiation fin 40. The heat radiation pattern 65 is formed using the surface of the motherboard 60. However, if a multi-layer substrate is used, the heat radiation can be further improved using the inner layer. Further, when the heat radiation fins 40 cannot directly contact the entire surface of the heat radiation pattern 65 with the insulating protection film of the motherboard 60 or the like, a pattern exposed land portion may be formed around the screw hole 66 of the heat radiation pattern 65. Heat dissipation can be promoted.

According to the above configuration, the driving transistor 2
The heat from 1 is directly absorbed and radiated to the case 70 having a large heat capacity through the ceramic substrate 10 and the heat radiation fins 40. At the same time, heat from the driving transistor 21 is conducted to the heat radiation pattern 65 formed on the motherboard 60 via the ceramic substrate 10 and the heat radiation fins 40, and is further absorbed and dissipated to the case 70 side.

As described above, the electronic control apparatus 100 to which the heat radiating device of the control apparatus of the present embodiment is applied has a ceramic in which the plurality of electronic components 21 and 22 including the driving transistor 21 as the heat-generating electronic component are mounted. The substrate 10, the motherboard 60 for electrically connecting the ceramic substrate 10 in a substantially vertical direction, the case 70 as a housing for housing the motherboard 60, and the ceramic substrate 10 are joined to absorb heat from the drive transistor 21 and the like. A radiating fin 40 as a radiating member to radiate,
Numeral 0 is screw-fixed to the radiation fins 40 using screws 68, and screwed together with the projections 41 of the radiation fins 40 to the projections 75 as the inner wall portion of the case 70 using screws 69 from the same direction. It is fixed. Further, the mother board 60 forms a heat radiation pattern 65 on the contact surface with the heat radiation fin 40.

That is, the mother board 60 is
0 is screwed and fixed to the radiating fins 40 using screws 68 and screwed to the projecting portions 75 of the case 70 with the radiating fins 40 interposed therebetween. The heat from the drive transistor 21 or the like of the substrate 10 can be reliably conducted directly to the case 70 side to efficiently absorb and radiate heat, thereby improving heat dissipation. In addition, workability is remarkably improved by simplifying the assembling work by screw fixing from only the same direction. Since the heat radiation pattern 65 is formed on the motherboard 60 and the heat radiation fins 40 are in contact with each other, the heat radiation fins 40 are
The heat can be efficiently absorbed and dissipated through 0, and the heat dissipation is further improved.

Embodiment 2 FIG. 4 is a cross-sectional view showing a main configuration of an electronic control apparatus 200 to which a heat radiating device for a control apparatus according to a second embodiment of the present invention is applied. In the drawings, the same reference numerals and symbols are given to components having the same configuration or corresponding portions as those in the cross-sectional view of FIG. 2 in the above-described embodiment, and detailed description thereof will be omitted. Also,
The overall configuration of the electronic control device 200 according to the present embodiment is the same as the perspective view of FIG. 1 in the above-described embodiment, and a detailed description thereof will be omitted.

In FIG. 4, the electronic control unit 2 of the present embodiment
In the case of 00, the radiating fins 40 to which the ceramic substrate 10 was joined in the configuration of the electronic control device 100 and the motherboard 60 to which lead terminals from the ceramic substrate 10 were soldered and electrically connected were housed in the case 70. Thereafter, a cover 80 as a cover member of the housing is further placed on the lower opening side of the case 70. Then, from the outside to the center of the cover 80, the cover 80 is screwed and fixed with the cover 80 via the mother board 60 and the radiation fins 40 using screws 88. Further, from the outside of the cover 80, the left and right peripheral portions of the motherboard 6 are attached with the cover 80.
0 and the projecting portion 7 of the case 70
5 is screwed and fixed using screws 89 from the same direction. Except for the screw fixing portion, the cover 80
Is formed at a predetermined distance from a soldered portion such as a lead terminal of an electronic component mounted on the motherboard 60.

As described above, the electronic control device 200 to which the heat radiating device of the control device of the present embodiment is applied has a ceramic in which the plurality of electronic components 21 and 22 including the driving transistor 21 as the heat-generating electronic component are mounted. The substrate 10, the motherboard 60 for electrically connecting the ceramic substrate 10 in a substantially vertical direction, the case 70 as a housing for housing the motherboard 60, and the ceramic substrate 10 are joined to absorb heat from the drive transistor 21 and the like. A radiating fin 40 as a radiating member to radiate,
0 is screwed and fixed to the radiating fins 40 from outside with a cover 80 as a cover member of the housing, and together with the projections 41 of the radiating fins 40 from outside with the cover 80 interposed therebetween. It is screwed and fixed to the protruding portion 75 as an inner wall portion of the housing from the same direction using screws 89.

That is, the mother board 60 is screwed and fixed to the radiating fins 40 from the outside with the cover 80, and the projections 41 of the radiating fins 40 are interposed from the outside with the cover 80 together with the projecting portions of the case 70. 75 from the same direction.
Drive transistor 2 of ceramic substrate 10 joined to
The heat from the first and the like can be directly and reliably conducted to the case 70 side so that it can be efficiently absorbed and dissipated. Further, the motherboard 60 is fixed to the cover 80 by screwing in contact with the cover 80, so that heat from the drive transistors 21 and the like of the ceramic substrate 10 joined to the radiating fins 40 can be conducted to the cover 80 side. The performance is further improved. Then, the assembling work by screwing and fixing is simplified to only from the same direction, and workability is remarkably improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration of an electronic control device to which a heat radiating device of a control device according to a first example and a second example of an embodiment of the present invention is applied.

FIG. 2 is a cross-sectional view showing a configuration of a main part of the electronic control device of FIG.

FIG. 3 is a partial plan view showing a heat dissipation pattern formed on the motherboard of FIG. 1;

FIG. 4 is a cross-sectional view illustrating a main configuration of an electronic control device to which a heat dissipation device for a control device according to a second example of the embodiment of the present invention is applied.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ceramic board 40 Heat radiation fin (heat radiation member) 60 Motherboard 65 Heat radiation pattern 70 Case (housing) 75 Projection part (inner wall part of housing) 80 Cover (housing) 100 Electronic control equipment

Claims (3)

[Claims] 1. A board on which a plurality of electronic components including an electronic component having heat generation are mounted; a motherboard electrically connecting the boards in a substantially vertical direction; a housing for housing the motherboard; A heat dissipating member that is in contact with or joined thereto and absorbs and dissipates heat from the electronic component; and the motherboard is screwed and fixed to the heat dissipating member, and the heat dissipating member is interposed therebetween to form an inner wall portion of the housing. A heat radiating device for control equipment, wherein the heat radiating device is fixed by screws from the same direction. 2. A substrate on which a plurality of electronic components including electronic components having heat generation are mounted; a motherboard electrically connecting the substrates in a substantially vertical direction; a housing for accommodating the motherboard; A heat dissipating member that is in contact with or joined to absorb and dissipate heat from the electronic component, wherein the motherboard is screwed and fixed to the heat dissipating member from outside with a lid member of the housing, and A heat radiating device for a control device, wherein the heat radiating member is interposed from the outside with a cover member of a body, and is screwed and fixed to an inner wall portion of the housing from the same direction. 3. The heat radiating device for a control device according to claim 1, wherein the mother board forms a heat radiating pattern on a contact surface with the heat radiating member.