WO2017047538A1

WO2017047538A1 - Electronic control device

Info

Publication number: WO2017047538A1
Application number: PCT/JP2016/076751
Authority: WO
Inventors: 紘文渡部; 斎藤　博之; 藤田　治彦
Original assignee: 日立オートモティブシステムズ株式会社
Priority date: 2015-09-17
Filing date: 2016-09-12
Publication date: 2017-03-23
Also published as: JP2017059693A

Abstract

In this motor control device (3) of an electric brake booster, a power module (16) is housed inside a housing (11) together with a control module (17). A relay (51) is mounted in the power module (16). Between the top surface (51b) of the relay (51) and the bottom surface of a case (12) in the housing (11), a heat conduction block (65) is arranged and is thermally connected. In extremely cold locales, after power source shut-off, the top surface of the relay (51) is cooled by heat conduction, so condensation is suppressed in the contact part. The heat conduction block (65) comprises a center opening (66), and the top surface center (51ba) of the relay case (70) is opened, so stress during thermal expansion is suppressed.

Description

Electronic control unit

This invention relates to an electronic control device provided with an electromagnetic relay.

In Patent Document 1, as a prior art, in a vehicle power supply device equipped with a relay, the top surface of the relay case is disposed through a heat conductive sheet in order to release heat generated inside the relay in an ON state. A configuration in contact with a vehicle chassis is disclosed.

In the above conventional configuration, the entire top surface of the relay case is subjected to a reaction force due to the elastic force of the heat conductive sheet and is pressed in the thickness direction of the heat conductive sheet. Therefore, when the relay case becomes hot due to heat generated during operation of the relay or ambient heat, stress is generated in the central portion of the top surface due to expansion of the top surface portion of the relay case, reducing the durability of the relay case. There are concerns.

JP 2014-79093 A

An electronic control device according to the present invention includes:
A relay in which an electromagnet and a contact portion opened and closed by the electromagnet are housed in a relay case;
A heat-generating component that generates heat during operation;
A circuit board on which the relay and the heat generating component are mounted;
An exterior member that houses the circuit board;
A heat conductive member having adhesiveness disposed between one surface of the relay case facing the inner surface of the exterior member and the inner surface of the exterior member;
With
The heat conducting member is
The relay case is joined to the surface in a region excluding the central portion of the surface.

According to the present invention, the central portion of the surface of the relay case that becomes the heat conducting surface is not constrained by the heat conducting member, so when the heat expands due to heat generated during operation of the relay or heat of surrounding heat generating components, Stress at the center is dispersed, and the occurrence of breakage and cracks is suppressed.

The disassembled perspective view which shows the electric brake booster provided with the motor control apparatus which is one Example of this invention. The exploded perspective view of the motor control device of this embodiment. The perspective view of a case single-piece | unit. It is the perspective view of a power module single-piece | unit, Comprising: The perspective view which looked at the power module from the component mounting surface side. Similarly, the top view which looked at the power module simple substance from the component mounting surface side. The enlarged view of the principal part of FIG. Sectional drawing along the AA line of FIG. FIG. 6 is a cross-sectional view of the entire motor control device taken along line BB in FIG. 5. Sectional drawing of the whole motor control apparatus along CC line of FIG. The top view which shows a power module and a cover in the state which removed the case. The enlarged view of the principal part of FIG. The perspective view which shows the heat conductive block of 1st Example with a relay. Sectional drawing which shows one structural example of a relay. The perspective view which shows the heat conductive block of 2nd Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 2nd Example. FIG. 16 is a cross-sectional view of the entire motor control device taken along line DD in FIG. 15. The perspective view which shows the heat conductive block of 3rd Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 3rd Example. FIG. 19 is a cross-sectional view of the entire motor control device taken along line EE in FIG. 18. The perspective view which shows the heat conductive block of 4th Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 4th Example. FIG. 22 is a sectional view of the entire motor control device taken along line FF in FIG. 21. The perspective view which shows the heat conductive block of 5th Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 5th Example. FIG. 25 is a sectional view of the entire motor control device taken along line GG in FIG. 24. The perspective view which shows the heat conductive block of 6th Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 6th Example. FIG. 28 is a cross-sectional view of the entire motor control device taken along line HH in FIG. 27. The perspective view which shows the heat conductive block of 7th Example with a relay. The top view similar to FIG. 10 provided with the heat conductive block of 7th Example. FIG. 31 is a sectional view of the entire motor control device taken along line II in FIG. 30.

Hereinafter, an embodiment in which the present invention is applied to an electronic control device for an electric brake booster will be described in detail with reference to the drawings.

FIG. 1 is an exploded perspective view showing an electric brake booster 1 provided with a motor control device 3 which is an electronic control device according to the present invention, and FIG. 2 is an exploded perspective view of the motor control device 3.

An electric brake booster 1 shown in FIG. 1 is attached to the engine room side of a dash panel (not shown) that partitions the automobile compartment and the engine compartment, and is illustrated according to the depression of a brake pedal provided on the compartment side. A booster mechanism for driving the master cylinder, and an electric motor 2 for driving the piston of the master cylinder (not shown) in the axial direction via a ball screw mechanism; And a motor control device 3 that drives and controls the electric motor 2 based on the state.

The electric motor 2 has a motor housing 4 made of a metal material such as an aluminum alloy, for example, and a cylindrical outer surface of the motor housing 4 is positioned between the pair of pedestal portions 5 and the pair of pedestal portions 5. And a controller mounting seat portion 6 to be formed. The motor control device 3 is mounted on the controller mounting seat 6 and is mounted and fixed to the motor housing 4 by screwing the device mounting screws 8 arranged at the four corners into the screw holes 7 of the base 5. Yes. The controller mounting seat portion 6 having a substantially rectangular wall shape has an opening 9 inside thereof, and the electric connection between the electric motor 2 side and the motor control device 3 is made through the opening 9. .

FIG. 1 generally corresponds to the posture of the electric brake booster 1 disposed in the engine room when mounted on the vehicle, and the motor control device 3 is mounted on the upper surface side of the motor housing 4 when mounted on the vehicle. ing.

As shown in FIG. 2, the motor control device 3 has a housing 11 corresponding to an “exterior member”. The housing 11 includes a case 12 positioned on the lower side when the vehicle is mounted and a cover 15 positioned on the upper side when mounted on the vehicle. The case 12 has a bottom wall 13 and a peripheral wall 14, and has a substantially rectangular shape in plan view with the upper surface opening upward. The cover 15 has a substantially rectangular shape in a plan view that closes the upper surface opening of the case 12. Inside the housing 11, a power module 16 corresponding to a “circuit board” is housed together with a control module 17 made of another circuit board. Specifically, the power module 16 is positioned near the bottom wall 13 of the case 12, and the control module 17 is laminated and disposed above the power module 16 with a predetermined interval.

The cover 15 is formed by press-molding a metal plate in a substantially dish shape, and has a flange portion 21 joined to the upper end of the peripheral wall 14 of the case 12 at the periphery, and accommodates the control module 17. Therefore, it has a shape bulging from the flange portion 21 toward the opposite side of the case 12. The cover 15 is fixed to the case 12 by cover mounting screws 22 arranged at four corners.

As shown in FIG. 3, the case 12 is molded by a so-called die casting method using a metal material having relatively good heat conduction, such as an aluminum alloy. The substantially rectangular peripheral wall 14 of the case 12 includes a first wall portion 14a and a third wall portion 14c that face each other, and a second wall portion 14b and a fourth wall portion 14d that face each other in a form orthogonal to them. Although it is configured, an opening 25 through which the external connector 24 of the power module 16 is inserted is cut out in a substantially U shape in the first wall portion 14a corresponding to one side thereof. In addition, a circular breathing hole 27 to which a breathing filter 26 (see FIG. 1) is attached from the outside is formed at one end of the fourth wall portion 14d. A plurality of cooling fins 28 are formed on the outer surface of the fourth wall portion 14d. The case 12 and the cover 15 are sealed with a sealant applied to the seal groove 29 at the upper end of the peripheral wall 14, and the periphery of the external connector 24 of the power module 16 is similarly applied by applying the sealant. 12 and the cover 15 are sealed.

The bottom wall 13 of the case 12 is formed with a plurality of substantially cylindrical power module support portions 31 protruding toward the cover 15 at a plurality of locations, and screw holes for attaching the power module 16 to each top portion. 32 is formed.

Further, at a position corresponding to a switching element mounting region, which will be described later, on the power module 16 side in the bottom wall 13, a block-shaped projecting portion 34 projecting from the bottom wall 13 toward the cover 15 is formed into a substantially rectangular block shape. Is formed. This block-shaped protrusion 34 functions as a heat sink having a large heat capacity. The block-shaped projecting portion 34 is located at a substantially central portion of the case 12 and has a predetermined interval with respect to the first wall portion 14a, the second wall portion 14b, and the third wall portion 14c of the rectangular peripheral wall 14. And are formed integrally and continuously with respect to the fourth wall portion 14d. A plurality of screw holes 32 for attaching the power module 16 are also formed in the vicinity of the four corners of the top surface of the block-shaped protrusion 34.

At the end of the block-shaped protrusion 34 on the fourth wall 14d side, a connector insertion hole 35 is formed in an elongated rectangular shape. Further, a stator terminal insertion hole 36 is formed in the bottom wall 13 between the block-shaped protruding portion 34 and the second wall portion 14b. The stator terminal insertion hole 36 is formed adjacent to the block-shaped projecting portion 34, that is, is formed in an elongated slit shape along the side surface of the block-shaped projecting portion 34 facing the second wall portion 14b. ing.

The power module 16 is molded using a synthetic resin material. As shown in FIGS. 4 and 5, a metal bus bar (not shown) is formed in a substantially flat plate shape and serves as circuit wiring. A plate-like base portion 41 having a large number inserted on the surface or inside thereof, the external connection connector 24 formed integrally with one end edge of the plate-like base portion 41, and a plane of the plate-like base portion 41 from the plate-like base portion 41. A stator connection terminal portion 43 and a sensor connector portion 44 projecting in the orthogonal direction are provided. As described above, the external connector 24 is exposed to the outside through the opening 25 of the case 12, and is connected to an electronic device on the vehicle side for transmission and reception of signals and electric power. Further, the stator connection terminal portion 43 located substantially at the center of the plate-like base portion 41 passes through the stator terminal insertion hole 36 of the case 12 described above. The sensor connector 44 located on the side of the plate-like base 41 passes through the connector insertion hole 35 of the case 12. The stator connection terminal portion 43 and the sensor connector portion 44 are finally connected to the stator and the sensor on the electric motor 2 side through the opening 9 of the controller mounting seat portion 6 of the electric motor 2, respectively.

4 and 5 show the lower surface of the power module 16 on the case 12 side, that is, the component mounting surface, on which a large number of electronic components (mainly power system components) are mounted. Specifically, from the plane of the six switching elements (for example, MOSFETs) 46 and the plate-like base 41 constituting a known inverter circuit that converts DC power supplied via the external connector 24 into three-phase AC power. A pair of first electrolytic capacitors 47 having an upright substantially cylindrical shape, and a pair of second electrolytic capacitors having a substantially cylindrical shape which is also upright from the plane of the plate-like base 41 and having a shorter axial length than the first electrolytic capacitor 47. 48, a plurality of ceramic capacitors 49, a plurality of shunt resistors 50 for detecting current, a pair of relays 51 for cutting off power for circuit protection, a normal mode coil 52 serving as a noise filter, and the like are mounted. The six switching elements 46 corresponding to “heat generating components” are collectively arranged in the form of “2 × 3” in a region corresponding to the block-shaped protrusion 34 of the case 12. The pair of relays 51 is disposed at a position opposite to the mounting region of the switching element 46 with the stator connection terminal portion 43 at the substantially central portion interposed therebetween.

As shown in FIG. 2, the power module 16 is combined with the case 12 in such a posture that the component mounting surface is the lower surface, and a plurality of power module mounting screws 53 are respectively screwed into the screw holes 32 on the case 12 side. It is fixed to the case 12. The peripheral portion of the power module 16 is fixed to the screw hole 32 of the substantially cylindrical power module support portion 31, and the central portion is fixed to the screw hole 32 of the block-shaped protruding portion 34. The various electronic components mounted on the power module 16 are accommodated in a space generated between the power module 16 and the case 12. At this time, the six switching elements 46 are located close to the top surface of the block-shaped protrusion 34, and each package has a block-shaped protrusion via a single heat conductive sheet as will be described later. 34 is joined to the top surface.

The control module 17 overlaid on the power module 16 is made of a printed wiring board using a resin substrate such as glass epoxy resin or a metal substrate, and a large number of control system electronic components (not shown) are mounted on both sides thereof. It is. As shown in FIG. 2, the control module 17 made of this printed wiring board has through holes 56 penetratingly formed at positions corresponding to a large number of connection terminals 55 extending upward from the upper surface of the power module 16. By soldering the connection terminal 55 and the through hole 56, necessary electrical connection is made between the power module 16. Then, a plurality of snap fit portions 57 integrally formed on the upper surface of the power module 16 engage with the notches 58 on the periphery of the control module 17, whereby the control module 17 is predetermined from the plate-like base portion 41 of the power module 16. It is fixedly held in a state where the interval is maintained.

Next, the configuration around the relay 51, which is a main part of the present invention, will be further described.

In this embodiment, the pair of relays 51 mounted on the power module 16 is a normally open type in which the contact is turned on when the electromagnet is energized, and each has a rectangular parallelepiped shape as shown in FIG. . In contrast to the relay 51 having a rectangular parallelepiped shape, the power module 16 made of synthetic resin is integrally formed with a pair of relay housing chambers 62 formed of relatively thin relay housing chamber walls 61. The relays 51 are fitted in the storage chambers 62, respectively.

6 and 7 are an enlarged plan view and a cross-sectional view showing a portion of the relay accommodating chamber 62, and the relay accommodating chamber wall 61 is formed of the plate-like base portion 41 of the power module 16 as shown in FIG. It is formed so as to stand vertically from a relay mounting surface 62a at the bottom of a part. And as shown in FIG. 6, the relay accommodating chamber wall 61 is extended so that the circumference | surroundings of the relay 51 may be enclosed in a rectangle.

Here, for convenience of explanation, for each surface of the relay 51 that forms a rectangular parallelepiped, that is, a hexahedron, the surface facing the relay mounting surface 62a is the bottom surface 51a, and the opposite surface is the top surface 51b. If the pair of surfaces along the short side are called side surfaces 51c and the pair of surfaces along the short side are called end surfaces 51d, the pair of relays 51 are parallel to each other with a relatively small distance between the side surfaces 51. They are arranged next to each other. Note that a plurality of terminals (a fixed contact terminal 74, a movable contact terminal 75, and a coil terminal 76 shown in FIG. 12), which will be described later, of the relay 51 protrude perpendicularly from the bottom surface 51a to the bottom surface 51a. The relay mounting surface 62a is welded or soldered to a bus bar (not shown) passing through the plate-like base 41 of the power module 16 and extending along the upper surface of the plate-like base 41 (the surface opposite to the relay mounting surface 62a). .

A relay accommodating chamber wall 61 for one relay 51 (indicated by reference numeral 51A in FIG. 6) has a first wall portion 61a along one side surface 51c, and extends perpendicularly from the first wall portion 61a. A second wall 61b along one end face 51d, a third wall 61c extending along the other side 51c of the relay 51, and the other end face of the relay 51, extending orthogonally from the second wall 61b. And a fourth wall portion 61d which is located opposite to 51d and has a substantially U shape in plan view. Therefore, the first wall portion 61a and the third wall portion 61c face each other with the relay 51 interposed therebetween, and the second wall portion 61b and the fourth wall portion 61d face each other with the relay 51 interposed therebetween.

The relay accommodating chamber wall 61 for the other relay 51 (shown as 51B in FIG. 6) is configured to be substantially symmetrical with the relay accommodating chamber wall 61 for the relay 51A, and similarly, along the one side surface 51c. The first wall 61a, the first wall 61a extending orthogonally from the first wall 61a, the second wall 61b along one end surface 51d of the relay 51, and the second wall 61b extending further orthogonally, A third wall portion 61c along the other side surface 51c of the relay 51, and a fourth wall portion 61d that is positioned opposite to the other end surface 51d of the relay 51 and has a substantially U shape in plan view. . The first wall portion 61a and the third wall portion 61c face each other with the relay 51 interposed therebetween, and the second wall portion 61b and the fourth wall portion 61d face each other with the relay 51 interposed therebetween.

The third wall portion 61c for one relay 51A and the third wall portion 61c for the other relay 51B are connected to each other by a pair of connecting portions 61e. Each of the second wall portions 61b includes a substantially U-shaped portion at the intermediate portion.

Accordingly, each of the relay accommodating chambers 62 is configured as a substantially rectangular recessed space surrounding the four surfaces around the relay 51, although the relay accommodating chamber wall 61 is not completely continuous. The relay 51 is inserted from the open surface, and mounted on the relay mounting surface 62a. In this state where the relay 51 is mounted, the top surface 51b of the relay 51 is exposed from the open surface of one end of the relay accommodating chamber 62. The substantially U-shaped recesses in the fourth wall portion 61d and the second wall portion 61b are filled with an adhesive having a relatively high viscosity after the relay 51 is mounted.

Here, the relay accommodating chamber wall 61 is located slightly away from the side surface 51c and the end surface 51d of the relay 51, and a gap serving as an air layer 63 is provided between them. Further, as shown in FIG. 7, the height from the relay mounting surface 62 a to the tip of the relay accommodating chamber wall 61 is slightly lower than the height to the top surface 51 b of the relay 51. The top portion slightly protrudes from the tip of the relay accommodating chamber wall 61. Thus, since the height of the relay accommodating chamber wall 61 is slightly low, the chuck of the automatic assembly machine for assembling the relay 51 is inserted into the relay accommodating chamber 62 while holding the top of the relay 51. It becomes possible to do. The difference in height between the two is desirably set to a minimum dimension capable of gripping the relay 51 by the chuck. Note that the leading edge of the relay accommodating chamber wall 61 has the same height in each part.

As shown in FIGS. 8 and 9, the pair of relays 51 arranged in the relay accommodating chamber 62 as described above are assembled with the case 12 or the like as the motor control device 3, and the top surface 51 b faces downward as shown in FIGS. 8 and 9. Each top surface 51b faces the bottom wall 13 of the case 12, more specifically, the bottom wall 13 in the region between the stator terminal insertion hole 36 and the second wall portion 14b. Between them, a heat conduction block 65 having a rectangular flat block shape is disposed as a “heat conduction member”. The heat conduction block 65 is made of a rubber-like material or a silicon-based material excellent in heat conduction, and has flexibility and surface adhesiveness. The heat conduction block 65 has an inner surface between the top surface 51b and the bottom wall 13 of the relay 51. It arrange | positions in the state compressed slightly between the side surfaces, and is closely_contact | adhered to each surface by this. Therefore, the top surface 51 b of the relay 51 is thermally connected to the bottom wall 13 of the case 12.

FIG. 10 shows the power module 16 having the heat conduction block 65 with the case 12 removed, and FIG. 11 shows an enlarged view of the main part of FIG. FIG. 12 is a perspective view showing one relay 51 and a heat conduction block 65. As shown in these drawings, the heat conduction block 65 of the first embodiment has a rectangular outer shape corresponding to the outer dimension of the top surface 51b forming the rectangle of the relay 51, and has a rectangular central opening in the central portion. 66. Accordingly, the heat conduction block 65 has a rectangular frame shape or a rectangular cylindrical shape. Thereby, in a state where the heat conduction block 65 is interposed between the relay 51 and the bottom wall 13 of the case 12, the heat conduction block 65 substantially has a central portion 51 ba (central opening portion 66) of the top surface 51 b of the relay 51. The region corresponding to the outer peripheral portion 51bb on the outer peripheral side than the region 51), and a space is secured by the central opening 66 for the central portion 51ba of the top surface 51b. The heat conduction block 65 is configured to be sufficiently thick (for example, having a thickness of 5 mm or more), and high followability can be obtained with respect to minute irregularities on the joint surface.

Further, as shown in FIGS. 10 and 9, the space between the six switching elements 46, which are heat generating components, and the top surface of the block-like protrusion 34 of the case 12 is thinner than the heat conduction block 65. A sheet-like heat conductive sheet 67 is interposed. This heat conductive sheet 67 is made of a rubber-like material or a silicon-based material excellent in heat conduction similar to the heat conductive block 65, has flexibility and surface adhesiveness, and protrudes from the package surface of the switching element 46 in a block shape. It is in close contact with the top surface of the portion 34. As a result, the heat of the switching element 46 in operation is dissipated to the block-shaped protrusion 34 serving as a heat sink.

The relay 51 used in the present invention is not necessarily limited to a specific configuration, but an example thereof is shown in FIG. As shown in the figure, the relay 51 has a synthetic resin-made relay case 70 composed of a plate-shaped base member 71 and a box-shaped cap 72 having an open end, and the base member 71 has a plurality of terminals (fixed contacts). A terminal 74, a movable contact terminal 75, and a pair of coil terminals 76) are attached by insert molding. In the illustrated example, the lower surface of the base member 71 is the bottom surface 51 a of the relay 51 described above, and the base member 71 is positioned on the relay mounting surface 62 a side of the power module 16. As described above, the terminals 74 to 76 are disposed through the relay mounting surface 62a, and are welded or soldered to a bus bar (not shown) included in the power module 16. Each of the outer surfaces of the cap 72 is the top surface 51b, the side surface 51c (not shown in FIG. 13) and the end surface 51d of the relay 51 described above.

A cylindrical coil 81, an iron core 82, and a substantially L-shaped yoke 83 are located on the upper side (ceiling wall 72 a (top surface 51 b)) of the internal space of the relay case 70 including the base member 71 and the cap 72. An electromagnet 80 is accommodated, and a contact portion 85 composed of a fixed contact 86 and a movable contact 87 is accommodated near the lower side of the internal space of the relay case 70 (base member 71 (bottom surface 51a)). That is, in the relay case 70, the contact portion 85 is located at a position relatively closer to the base member 71 than the coil 81, and the ceiling wall 72 a (in other words, the top surface 51 b) of the cap 72 is reversed to the contact portion. Located at a distance from 85. Therefore, the distance from the contact portion 85 to the ceiling wall 72a (top surface 51b) is larger than the distance from the contact portion 85 to the base member 71 (bottom surface 51a).

The fixed contact 86 is attached to the end portion of the fixed contact terminal 74 bent in an L shape so as to follow the inner surface of the base member 71, and the movable contact 87 positioned opposite thereto is a leaf spring 88. And is connected to the movable contact terminal 75 via the leaf spring 88. An L-shaped magnetic plate 89 is supported so as to swing around a fulcrum portion 89 a as a swing center, one end 89 a of which opposes the end of the iron core 82, and the other end 89 b to the leaf spring 88. It is linked. Accordingly, when the coil 81 is energized from the coil terminal 76, the magnetic plate 89 swings and presses the leaf spring 88 downward in the drawing, and the movable contact 87 contacts the fixed contact 86. When the coil 81 is de-energized, the movable contact 87 is separated from the fixed contact 86 by the leaf spring 88.

Such a relay 51 itself is publicly known, and is described in, for example, Japanese Unexamined Patent Application Publication Nos. 2009-283255 and 2004-172036. In the present invention, various known types of relays can be applied.

In the configuration of the embodiment described above, it is possible to suppress the occurrence of condensation on the contact portion 85 of the relay 51 in an extremely cold region.

That is, although the relay case 70 has a sealed structure, surrounding moisture penetrates into the relay case 70 due to moisture permeability of the synthetic resin material constituting the relay case 70. For example, assuming a very cold region that reaches 20 ° below freezing point, the inside of the housing 11 of the motor control device 3 is about 0 ° C. to 5 ° C. during the operation of the vehicle (that is, during the operation of the motor control device 3). The water in the relay case 70 is in a vaporized state, but thereafter, when the operation of the vehicle is finished and the power source of the motor control device 3 is shut off, the metal members such as the bus bars of the power module 16 and the terminals of the connector The temperature of the contact portion 85 (fixed contact 86, movable contact 87) that is thermally connected to the outside air via the temperature decreases to below freezing point, and the vaporized moisture in the relay case 70 becomes the contact 86. , 87 may cause condensation on the surface. Since the

contacts

86 and 87 have a small heat capacity, condensation is likely to occur. If condensation occurs in the contact portion 85 while the vehicle is stopped in this manner, contact failure at the contact portion 85 may occur when the power is turned on to start operation of the vehicle.

With respect to such a problem, in the configuration of the above-described embodiment, the relay is connected to the metal case 12 exposed to the outside air via the heat conduction block 65 after the power source of the motor control device 3 is shut off in the extremely cold region. Since the top surface 51b of 51 is thermally connected, the temperature of the ceiling wall 72a of the relay case 70 quickly decreases, and the water vaporized in the relay case 70 is condensed on the inner surface of the ceiling wall 72a. . The heat transfer path to the

contacts

86 and 87 via the bus bars and the like described above is thin and long, whereas the heat transfer path to the ceiling wall 72a via the heat conduction block 65 is wide and short. Even if it is made of synthetic resin, the temperature rapidly decreases. Therefore, dew condensation at the

contacts

86 and 87 located away from the ceiling wall 72a and close to the base member 71 is suppressed.

Particularly, in the relay 51, the top surface 51b of the relay case 70, that is, the ceiling wall 72a is in contact with the bottom wall 13 of the case 12 via the heat conduction block 65, and the ceiling wall 72a is locally cooled by heat conduction. On the other hand, since the portion other than the ceiling wall 72a is surrounded by the relay accommodating chamber wall 61 via the air layer 63 and is kept warm by the air layer 63, the temperature drop is relatively slow. Therefore, the temperature of the inner surface of the ceiling wall 72a is lowered earlier than the temperature of the

contacts

86 and 87, and moisture in the relay case 70 is collected on the ceiling wall 72a as condensation.

Further, in the vehicle-mounted state, the

contacts

86 and 87 in the relay case 70 are located above the ceiling wall 72a and the ceiling wall 72a is at the bottom, so that the temperature distribution due to air convection in the relay case 70 However, the

upper contacts

86 and 87 are more likely to maintain a higher temperature than the lower ceiling wall 72a. If dew condensation occurs in a portion other than the ceiling wall 72a in the relay case 70, the water drops grow and try to collect on the lower ceiling wall 72a by its own weight. The condensation of 87 is more reliably suppressed.

On the other hand, when the heat conductive sheet is disposed on the entire top surface of the relay case as in Patent Document 1 described above, there is a concern that cracks and the like may occur due to stress associated with expansion of the relay case when the relay becomes hot, In the above embodiment, the frame-like heat conduction block 65 contacts the outer edge portion of the ceiling wall 72a (that is, the outer edge portion 51bb of the top surface 51b), and the center portion (that is, the top surface 51b) of the ceiling wall 72a that most easily expands due to thermal expansion. Since the central portion 51ba) is opened by the central opening 66, the stress at the central portion of the ceiling wall 72a is relieved, and the occurrence of breakage and cracks is suppressed. Moreover, since the heat conduction block 65 is thick in the height direction of the relay 51, the expansion / contraction of the ceiling wall 72a can be easily absorbed. Therefore, the durability of the relay case is improved. Note that the heat conduction block 65 is also disposed on the outer edge 51bb on the outer peripheral side of the central portion of the ceiling wall 72a corresponding to the central opening 66 (that is, the central portion 51ba of the top surface 51b). Since it is surrounded by the heat conduction block 65, the temperature decrease is also promoted by heat conduction through the heat conduction block 65, and as described above, condensation can be generated on the inner surface thereof.

It should be noted that the “center portion” of the rectangular top surface 51b means a portion including the intersection of two diagonal lines of the top surface 51b. Therefore, by forming the central opening 66, at least the intersection is located inside the central opening 66 without being covered by the heat conduction block 65.

Next, a second embodiment of the heat conduction block 65 will be described with reference to FIGS. As shown in FIG. 14, the heat conduction block 65 of the second embodiment has the rectangular shape of the first embodiment described above so as to cover the top surfaces 51 b of the two relays 51 with one heat conduction block 65. A frame-shaped heat conduction block 65 is connected by two connecting portions 67. In addition, rectangular cutouts 68 corresponding to the distance between the pair of relays 51 are provided on the outside of the connecting portion 67. That is, as a whole, the figure has an 8-shape having a pair of central openings 66.

According to such a configuration, the central portion of the ceiling wall 72a of each relay 51 (the central portion 51ba of the top surface 51b) is also opened by the central opening 66, so that stress during thermal expansion can be relieved. it can. Further, compared to the first embodiment described above, the area of the heat transfer surface in contact with the bottom wall 13 of the case 12 is increased, and the number of assembling steps of the heat conduction block 65 is reduced.

As in the first embodiment described above, the heat conduction block 65 is disposed at the outer edge 51bb on the outer peripheral side of the central portion 51ba of the top surface 51b corresponding to the central opening 66, so that the heat conduction block The heat conduction through 65 also promotes a decrease in temperature and can cause condensation on the inner surface.

Here, in the configuration provided with the notch portion 68 as described above, the notch portion 68 is positioned between the third wall portions 61 c of the pair of relay accommodating chamber walls 61, so that the heat conduction block 65 with respect to the relay 51 is arranged. Positioning is easy. Further, by inserting a flat jig between the pair of relay accommodating chamber walls 61 and placing the heat conduction block 65 while applying the jig to the notch 68, the above positioning operation is facilitated. Improves attachment and reduces assembly man-hours.

Further, when the power module 16 and the control module 17 are accommodated in the case 12 and the cover 15 is assembled, the heat conduction block 65 that is compressed and deformed by the top surface 51b of the relay 51 and the inner surface of the case 12 is notched. It becomes easy to escape to the space produced by the part 68, and as a result, the adhesiveness of each surface improves.

Similarly, when the pressing force of the heat conduction block 65 increases due to the thermal expansion of the cover 15, the heat conduction block 65 easily escapes into the space formed by the notch 68. Since the heat conduction block 65 swelled in the space is restored, adhesion to heat shrinkage is improved.

In the second embodiment, the heat conduction block 65 can be formed in a shape that does not include the notch 68.

Next, a third embodiment of the heat conduction block 65 will be described with reference to FIGS. In the third embodiment, as shown in FIG. 17, a heat conduction block 65 having a rectangular block shape is disposed across the top surfaces 51 b of the pair of relays 51. The heat conduction block 65 has a rectangular outer shape smaller than one top surface 51 b so as not to overlap the central portion 51 ba of the top surface 51 b of each relay 51, and covers the portions inside the pair of relays 51. ing.

According to this embodiment, since the central portion 51ba of the top surface 51b of the relay 51 is still open, the stress during thermal expansion can be relieved.

It should be noted that also in the central portion 51ba of the top surface 51b, the temperature decrease is also promoted by heat conduction through the heat conduction block 65, and condensation can be generated on the inner surface thereof.

In the third embodiment, the central portion 51ba of the top surface 51b does not overlap the heat conduction block 65 between the pair of end surfaces 51d of each relay 51. It is more preferable in terms of relaxation.

Next, a fourth embodiment of the heat conduction block 65 will be described with reference to FIGS. In the fourth embodiment, two relatively small heat conduction blocks 65 are arranged apart from each other in each of the pair of relays 51. As shown in FIG. 20, each heat conduction block 65 has a length equal to the width of the end surface 51 d of the relay 51 (that is, the short side of the relay 51) and the width of the side surface 51 c of the relay 51 (that is, the relay 51. A rectangular block shape having a thickness smaller than half of the long side). And the two heat conductive blocks 65 are each arrange | positioned in the position close | similar to the end surface 51d on the top surface 51b. In other words, the two standing wall-like heat conduction blocks 65 are arranged in parallel to each other with a gap therebetween.

Therefore, on the top surface 51b of each relay 51, the two heat conducting blocks 65 are joined to the region excluding the central portion 51ba of the top surface 51b, and the central portion 51ba of the top surface 51b is open. Thereby, the stress at the time of thermal expansion can be relieved.

In the fifth embodiment shown in FIGS. 23 to 25, the small heat conduction block 65 of the fourth embodiment is provided on the top surface 51b of each relay 51 only on one side. In this case, in consideration of the internal configuration of the relay 51 illustrated in FIG. 13, it is preferable to dispose the heat conduction block 65 on the side far from the contact portion 85.

Next, a sixth embodiment of the heat conduction block 65 will be described with reference to FIGS. In the heat conduction block 65 of the sixth embodiment, the main body portion 65A has a rectangular outer shape corresponding to the outer dimension of the top surface 51b of the relay 51, similarly to the heat conduction block 65 of the first embodiment. A rectangular central opening 66 is provided in the central portion, and a thin-walled portion 65B is provided in the central opening 66 of the main body 65A as a second heat conducting member that can be relatively easily deformed. . The thin-walled portion 65B can be integrally formed using, for example, a heat conductive material that is the same as that of the main body portion 65A, or a separately formed member is press-fitted into the central opening 66. It may be integrated. The thin portion 65B may be made of a material different from that of the main body portion 65A. In the illustrated example, the thin portion 65B is formed so as to constitute a part of one heat transfer surface that is in close contact with the bottom wall 13 of the case 12, and between the central portion 51ba of the top surface 51b of the relay 51. A space is formed.

Therefore, as in the above-described embodiments, the stress at the central portion 51ba of the top surface 51b during thermal expansion is relieved. According to the sixth embodiment, the area of the heat transfer surface with respect to the bottom wall 13 of the case 12 can be increased compared to the first embodiment. That is, since the heat conduction block 65 is in contact with the case 12 even in the thin portion 65B, the heat transfer area can be increased and the temperature drop of the top surface 51b of the relay 51 can be promoted.

It should be noted that the thin portion 65B can be provided to be shifted to the relay 51 side. Even if the configuration is in contact with the top surface 51b of the relay 51, the thin-walled portion 65B can be easily deformed as compared with the main body portion 65A, so that excessive stress during thermal expansion is suppressed.

Next, a seventh embodiment of the heat conduction block 65 will be described with reference to FIGS. In the heat conduction block 65 of the seventh embodiment, the main body portion 65A has a rectangular outer shape corresponding to the outer dimension of the top surface 51b of the relay 51, similarly to the heat conduction block 65 of the first embodiment. As a second heat conductive member having a rectangular central opening 66 in the central portion and relatively easily deformed in the central opening 66 of the main body 65A, heat conduction different from that of the main body 65A. A low reaction force portion 65C made of a conductive material is provided. The low reaction force portion 65C is made of a material having a smaller elastic force, that is, a reaction force than the main body portion 65A, has the same thickness as the main body portion 65A, and has a top surface 51b of the relay 51 and a bottom surface of the case 12. It is in contact with both the wall 13. The low reaction force portion 65C may be formed integrally with the main body portion 65A using different materials, or may be formed separately and press-fitted into the central opening 66.

According to the seventh embodiment, since the reaction force against the displacement of the central portion 51ba of the top surface 51b is small, the stress at the central portion 51ba of the top surface 51b during thermal expansion is relieved as in each of the embodiments. Further, according to the seventh embodiment, there is an advantage that a large area of the heat transfer surface with respect to the top surface 51b of the relay 51 and the bottom wall 13 of the case 12 can be obtained.

In each of the above embodiments, each relay 51 has a posture in which the

terminals

74, 75, 76 of the relay 51 protrude toward the plane of the plate-like base 41 of the power module 16, that is, the relay mounting surface 62 a of the relay accommodating chamber 62. However, the present invention is not limited to this, and the present invention can be similarly applied to a configuration in which the relay 51 is mounted in a posture in which these

terminals

74, 75, and 76 protrude to the side. is there.

The present invention can be applied not only to the motor control device 3 for the electric brake booster of the above embodiment but also to various electronic control devices.

As described above, the electronic control device of the present invention includes an electromagnet and a relay in which a contact portion opened and closed by the electromagnet is housed in a relay case, a heat generating component that generates heat in an operating state, the relay, and the heat generating component. A circuit board on which the circuit board is mounted; an exterior member that accommodates the circuit board; and an adhesive disposed between one surface of the relay case facing the inner surface of the exterior member and the inner surface of the exterior member. And the heat conductive member is joined to the surface in a region excluding the central portion of the surface of the relay case.

As a result, the temperature of a part of the relay case can be quickly lowered by heat conduction after the operation stops in a very cold region, etc., and condensation due to moisture in the relay case is generated on the inner wall of the relay case away from the contact point. Collecting and dew condensation at the contact portion can be suppressed. And when the relay case is thermally expanded due to the heat generated by the relay itself or the heat-generating parts during operation, the reaction force acting on the center of the surface of the relay case is small. It is suppressed that it leads to a crack.

In a preferred embodiment, the heat conducting member is configured in a rectangular frame shape having a central opening corresponding to the central portion of the surface. Thereby, a space is formed toward the central portion of the above surface, and stress during thermal expansion is suppressed.

Furthermore, in one aspect, a second heat conducting member that is relatively easily deformed is provided in the central opening. Thereby, the area of a heat-transfer surface expands, suppressing the stress of a center part.

In a preferred embodiment, a heat conducting member smaller than the above surface is joined to a portion of the above surface that is offset from one side except for the central portion. Even in such an embodiment, the stress in the central portion can be suppressed.

Also, in one preferred embodiment, two relays are arranged adjacent to each other, and one heat conducting member is arranged across both of the two relays so as to cover the adjacent areas. Even in such an embodiment, the stress in the central portion can be suppressed. In addition, the number of assembling steps for the heat conducting member is reduced.

In a preferred embodiment, the heat conducting member is made of a rubber-like material or a silicon-based material and has flexibility.

In a preferred embodiment, the heat conducting member has a block shape with a thickness of 5 mm or more.

And in one desirable mode, the above-mentioned heat conduction member is arranged in the state where it was compressed between the above-mentioned surface of the above-mentioned relay, and the inner surface of the above-mentioned exterior member which this surface opposes.

In a preferred embodiment, the relay includes a plurality of terminals on the bottom surface opposite to the surface.

The electronic control device of the present invention is, for example, a motor control device for an electric brake booster mounted on a vehicle.

In a preferred embodiment, the surface of the relay is rectangular, and the intersection of two diagonal lines of the rectangle is not covered by the heat conducting member.

Claims

A relay in which an electromagnet and a contact portion opened and closed by the electromagnet are housed in a relay case;
A heat-generating component that generates heat during operation;
A circuit board on which the relay and the heat generating component are mounted;
An exterior member that houses the circuit board;
A heat conductive member having adhesiveness disposed between one surface of the relay case facing the inner surface of the exterior member and the inner surface of the exterior member;
With
The heat conducting member is
An electronic control device joined to the relay case in a region excluding the central portion of the surface of the relay case.
The electronic control device according to claim 1, wherein the heat conducting member is configured in a rectangular frame shape having a central opening corresponding to the central portion of the surface.
The electronic control device according to claim 2, wherein a second heat conducting member that is relatively easily deformed is provided in the central opening.
The electronic control device according to claim 1, wherein a heat conductive member smaller than the surface is joined to a portion of the surface that is offset from one side except the central portion.
2. The electron according to claim 1, wherein two relays are arranged adjacent to each other, and one heat conducting member is arranged across both of the two relays so as to cover a region adjacent to each other. Control device.
6. The electronic control device according to claim 1, wherein the heat conducting member is made of a rubber-like material or a silicon-based material and has flexibility.
The electronic control device according to any one of claims 1 to 6, wherein the heat conducting member has a block shape having a thickness of 5 mm or more.
The heat conduction member is disposed in a compressed state between the surface of the relay and the inner surface of the exterior member facing the surface. The electronic control device described.
The electronic control device according to any one of claims 1 to 8, wherein the relay includes a plurality of terminals on a bottom surface opposite to the surface.
The electronic control device according to any one of claims 1 to 9, wherein the electronic control device is a motor control device of an electric brake booster mounted on a vehicle.
The electronic control device according to any one of claims 1 to 10, wherein the surface of the relay is rectangular, and an intersection of two diagonal lines of the rectangle is not covered by the heat conducting member.