JP6225806B2 - Electrical circuit device - Google Patents

Description

  The present invention relates to an electric circuit device.

  In an electric circuit device including a semiconductor element that generates heat during operation, such as a power switching element, various heat dissipation measures are taken to suppress problems caused by temperature rise. For example, in the technique described in Patent Document 1, a cooler having a cooling fan, a semiconductor element disposed on the cooler, a U-shaped radiator provided over the semiconductor element, and a cooler In a power converter provided with a cover member provided so as to cover, a spring member is interposed between the U-shaped radiator and the cover member. In this case, the semiconductor element is brought into close contact with the cooler and the U-shaped radiator by the spring force of the spring member, so that the heat generated in the semiconductor element is released through the cooler and the U-shaped radiator. .

JP 2012-227344 A

  However, the following disadvantages are considered to exist in the above-described prior art. That is, in the above prior art, a U-shaped radiator, a spring member, and a cover member are assembled from the opposite side of the cooler with the semiconductor element in contact with one surface of the cooler. On the other hand, the cover member is fixed with a bolt or the like, and there is a concern that workability when performing the assembly work is low. In this case, it is considered that the number of parts for assembling is large, and the arrangement and fixing of each member from one side to the cooler are inconvenient factors. For example, when the semiconductor mounting surface of the cooler is not horizontally upward, the assembling property is considered to be further deteriorated.

  The main object of the present invention is to provide an electric circuit device capable of adding appropriate element cooling performance while simplifying the configuration.

  Hereinafter, means for solving the above-described problems and the effects thereof will be described.

  The present invention is an electric circuit device having a semiconductor element (27) that generates heat during operation, and is provided with a base member (13) having an element cooling function and an outer surface of the semiconductor element provided on the base member. In a state where the plate-shaped heat receiving part (32) having the heat receiving surface to be brought into contact with the outer surface of the semiconductor element and the heat receiving surface of the heat receiving part, the semiconductor element and the heat receiving part are paired with a pair of sandwiching parts (41 ) And a clip member (40) that holds the contact state by elastic force.

  In the above configuration, the semiconductor element is provided in contact with the heat receiving surface of the heat receiving portion provided in the base member, and the semiconductor element and the heat receiving portion are sandwiched between the pair of holding portions of the clip member, so that the clip The contact state between the semiconductor element and the heat receiving portion is maintained by the elastic force of the member. In this case, the clip member is held at a predetermined mounting position by the elastic force of the member itself, and has a function of pressing the semiconductor element against the heat receiving portion in the mounted state. And the heat transfer from a semiconductor element to a heat receiving part can be appropriately implemented by maintaining the contact state of a semiconductor element and a heat receiving part. In addition, when mounting, work such as screw fixing is not required, and the number of parts can be reduced, and mounting work is simplified. As described above, appropriate element cooling performance can be added while simplifying the configuration.

Sectional drawing which shows the structure of the principal part about a power converter device. The exploded view of a power converter. Sectional drawing which expands and shows the clamping part of a semiconductor element. The top view which shows a part of structure of a case main body. Sectional drawing which shows the structure of another example about a power converter device. Sectional drawing which shows the structure of another example about a power converter device. Sectional drawing which shows the structure of another example about a power converter device. The top view which shows a part of structure of a case main body in another example.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings. In the present embodiment, the electric circuit device of the present invention is embodied as a power conversion device, and the power conversion device has an element cooling function for a semiconductor element that performs a switching operation at a predetermined switching cycle. 1-3, the structure of the principal part about the power converter device 10 is shown.

  As an outline, the power conversion device 10 includes a housing case 11 formed of a metal material such as aluminum, and a conversion circuit unit 12 housed in the housing case 11. The housing case 11 has a bottomed box-shaped case body 13 and a cover 14 that is assembled on the case body 13 and closes an open portion of the case body 13. The case body 13 corresponds to a “base member”, and the case body 13 is provided with an element cooling function. Further, the cover 14 corresponds to a “lid member”.

  The case main body 13 includes a bottom portion 21 and a peripheral wall portion 22 provided at the peripheral edge portion of the bottom portion 21. The bottom portion 21 is formed with a refrigerant passage 23 for circulating cooling water as a cooling medium. As the cooling water flows through the refrigerant passage 23, heat generated in the power conversion device 10 is transmitted to the cooling water, and heat is radiated. Note that a gas other than the liquid can be used as the cooling medium, and air (cold air) may be circulated in the refrigerant passage 23.

  A plurality of bosses 24 are formed on the bottom 21, and the circuit board 26 is fixed with screws or the like while being placed on the bosses 24. Thereby, the circuit board 26 is fixed at a position facing the bottom 21. Various electric components constituting the conversion circuit unit 12 are mounted on the circuit board 26. Note that any one of the electrical components constituting the conversion circuit unit 12 may be mounted on the bottom 21, and the electrical component mounted on the bottom 21 is electrically connected to the circuit board 26 via a metal terminal or a harness. . In FIG. 1 etc., the semiconductor element 27 which consists of switching elements, such as MOSFET, is shown as an electrical component, for example. The semiconductor element 27 is mounted vertically in the direction orthogonal to the substrate surface near the peripheral edge of the circuit board 26.

  The semiconductor element 27 has a main body portion 27a and a plurality of terminal portions 27b, and the terminal portions 27b are inserted into through holes (not shown) of the circuit board 26. As a result, the semiconductor element 27 is mechanically and electrically connected to the circuit board 26. The main body 27a has a rectangular parallelepiped exterior package, and in the exterior package, a heat radiating plate 27c is provided on the wide side of the wide side and the narrow side. The heat radiating plate portion 27c is, for example, a metal plate. The heat radiating plate portion 27 c is exposed on the outer surface of the element, and the heat radiating plate portion 27 c comes into contact with the case main body 13 so that heat is radiated from the semiconductor element 27 to the case main body 13.

  The upper end surface (specifically, the upper end surface of the portion having the largest wall height) of the peripheral wall portion 22 of the case body 13 is a cover mounting surface 22a on which the cover 14 is mounted, and is mounted on the cover mounting surface 22a. The cover 14 is fixed in the placed state. In this case, a through hole 14 a is formed in the cover 14, and a screw hole 22 b is formed in the peripheral wall portion 22, and a screw 28 is inserted into the through hole 14 a and the screw hole 22 b and the case main body 13 is inserted. The cover 14 is fixed.

  The cover 14 is fixed in close contact with the cover placement surface 22 a of the peripheral wall portion 22, whereby the housing case 11 is sealed. In addition, the joint part of the cover mounting surface 22a of the surrounding wall part 22 and the cover 14 may be sealed (water-stopped) by a sealing member such as a liquid gasket.

  In the present embodiment, there is a feature in the method of fixing the semiconductor element 27 to the case body 13, and the feature portion will be described below.

  A groove portion 31 is formed in the peripheral wall portion 22 at a position inside the case relative to the cover placement surface 22 a, and a portion inside the case from the groove portion 31 is a plate-shaped heat receiving portion 32. The groove portion 31 is formed to open to the upper end side (the tip end side opposite to the bottom portion 21) of the peripheral wall portion 22 and to extend in parallel to the inner peripheral surface of the peripheral wall portion 22. The heat receiving portion 32 is provided upright in a direction perpendicular to the bottom surface of the case, and the position of the upper end portion (the height position with respect to the bottom portion 21) is lower than the cover placement surface 22a. The case inner peripheral surface side of the heat receiving portion 32 is a heat receiving surface with which the outer surface of the semiconductor element 27 is brought into contact, and the heat radiating plate portion 27c of the semiconductor element 27 is brought into contact with the heat receiving surface.

  When the case main body 13 is shown in a plan view, as shown in FIG. 4, the groove portion 31 is formed in an elongated shape along the longitudinal direction of the peripheral wall portion 22. That is, the groove 31 is formed in a long shape so as to be continuous at each position where the plurality of semiconductor elements 27 are clip-fixed. In FIG. 4, the groove portion 31 is formed continuously on the two sides of the case body 13 via the corner portion of the case body 13, but not limited to this, the groove portion 31 is formed only on one side. It may be configured.

  Returning to the description of FIGS. 1 to 3, the semiconductor element 27 and the heat receiving portion 32 are in contact with each other, and the clip 40 is assembled to both of them in the contact state. The clip 40 is a clamping member having a pair of clamping parts 41 facing each other and a connecting part 42 therebetween, and is made of a metal material or a synthetic resin material having elasticity and high thermal conductivity. The pair of sandwiching portions 41 has a plate shape, and has a surface contact portion 41 a that makes surface contact with the semiconductor element 27 and the heat receiving portion 32. One of the pair of sandwiching portions 41 is in contact with the side surface portion of the semiconductor element 27 opposite to the heat radiating plate portion 27 c, and the other is in contact with the side surface portion of the heat receiving portion 32 in the groove portion 31. In this case, the heat generated in the semiconductor element 27 is transmitted to the heat receiving part 32 side through the contact part between the semiconductor element 27 and the heat receiving part 32, and the clip 40 has high thermal conductivity. Therefore, the heat is transmitted from the opposite side of the heat receiving portion 32 to the heat receiving portion 32 via the clip 40.

  Before the clip is mounted, the gap dimension (B in FIG. 2) between the pair of sandwiching portions 41 of the clip 40 is the thickness dimension of the semiconductor element 27 and the heat receiving portion 32 in a state of being superimposed (A in FIG. 2). ) Is smaller than. Therefore, when the clip 40 is attached, the semiconductor element 27 and the heat receiving part 32 are sandwiched between the pair of holding parts 41, and the semiconductor element 27 and the heat receiving part 32 are held in pressure contact with each other by the elastic force of the clip 40. The

  The groove 31 is filled with heat radiation grease G (see FIG. 3). The heat dissipating grease G is, for example, a paste material containing silicon as a main component. The heat dissipating grease G is filled in the groove 31 in a softened state and then cured. In the configuration of FIG. 1 and the like, the wall height is greater on the outer side of the case and on the inner side of the case (heat receiving portion 32) with the groove portion 31 in the peripheral wall portion 22 therebetween. Therefore, when the groove portion 31 is filled with the heat dissipation grease G, the heat dissipation grease G is less likely to protrude outward from the case body 13.

  In the present embodiment, a plurality of semiconductor elements 27 arranged side by side are brought into contact with the heat receiving portion 32, and the clips 40 are attached to the respective semiconductor elements 27 as shown in FIG. In FIG. 4, the width dimension of the clip 40 is made smaller than the width dimension of the semiconductor element 27, but these width dimensions can be made the same or the width dimensions can be reversed. .

  The clip 40 is attached from the front end side of the peripheral wall portion 22, and in the attached state, the drop is regulated by the cover 14. That is, as shown in FIG. 3, when the clip 40 is mounted, the separation dimension C from the upper end of the semiconductor element 27 to the surface contact portion 41 a of the clamping portion 41 is the lower surface of the clip 40 (joining portion 42) and the cover 14. It is larger than the clearance dimension D between. Thereby, even if the position of the clip 40 is shifted upward in the drawing, the range of the deviation is limited, and in any case, the state where the semiconductor element 27 and the heat receiving portion 32 are held by the clip 40 is maintained.

  According to the embodiment described in detail above, the following excellent effects can be obtained.

  The semiconductor element 27 and the heat receiving portion 32 of the peripheral wall portion 22 are sandwiched by a pair of holding portions 41 of the clip 40, and the contact state between the semiconductor element 27 and the heat receiving portion 32 is maintained by the elastic force of the clip 40. In this case, the clip 40 is held at a predetermined mounting position by the elastic force of the member itself, and has a function of pressing the semiconductor element 27 against the heat receiving portion 32 in the mounting state. And the heat transfer from the semiconductor element 27 to the heat receiving part 32 can be appropriately implemented by maintaining the contact state between the semiconductor element 27 and the heat receiving part 32. In addition, when mounting, work such as screw fixing is not required, and the number of parts can be reduced, and mounting work is simplified. As described above, appropriate element cooling performance can be added while simplifying the configuration.

  A groove portion 31 is formed in the peripheral wall portion 22 of the case body 13, and the clip 40 is mounted using the groove portion 31. In this case, the heat receiving portion 32 to which the clip 40 can be attached can be formed on the inner side of the case on the peripheral wall portion 22 than the cover placement surface 22a, and the clip can be attached to the peripheral wall portion 22 regardless of the fixing of the cover 14. ing. That is, the heat radiating function of the semiconductor element 27 can be suitably imparted to the peripheral wall portion 22 without affecting the airtightness and waterproofness of the case body 13 and the cover 14.

  In the configuration in which the semiconductor element 27 is vertically mounted on the circuit board 26, the clip 40 is mounted from the front end side of the peripheral wall portion 22, and the clip 14 is prevented from falling off by the cover 14 in the clip mounted state. . Thereby, even if it does not fix the clip 40 with fixing means, such as a screw, inconvenience that the clip 40 comes off unintentionally can be suppressed.

  In the configuration in which element cooling of the plurality of semiconductor elements 27 arranged side by side is performed, the groove 31 is continuously formed in a long shape. In this case, it is possible to suitably cope with a design change such as arrangement of the semiconductor element 27 mounted on the substrate. Moreover, according to this structure, when filling the thermal radiation grease G in the groove part 31, the merit that the filling operation becomes easy is also acquired.

  Since the groove portion 31 is filled with the heat radiation grease G, heat transfer from the semiconductor element 27 can be improved in the peripheral wall portion 22. That is, if the groove portion 31 exists as a space in the peripheral wall portion 22, heat dissipation from the semiconductor element 27 to the peripheral wall portion 22 may be deteriorated (heat transmission may be deteriorated), but heat is dissipated in the groove portion 31. By filling with grease G, a decrease in heat dissipation can be suppressed.

  The wall height of the outer side of the case and the inner side of the case is increased with the groove 31 interposed therebetween in the peripheral wall 22. Thus, when the groove portion 31 is filled with the heat radiation grease G, the heat radiation grease G is less likely to protrude outward from the case body 13. Therefore, it is only necessary to fill the heat dissipation grease G with reference to the wall height inside the case (that is, the wall height of the heat receiving portion 32), and a configuration suitable for taking into account the heat received from the semiconductor element 27 can be realized.

  Since the clip 40 is formed of a metal plate having high thermal conductivity, a heat dissipation path is also formed in the clip itself, which can contribute to improvement in heat dissipation. Further, since the pair of sandwiching portions 41 are in surface contact with the semiconductor element 27 and the heat receiving portion 32, respectively, it is possible to contribute to the improvement of heat dissipation.

(Other embodiments)
You may change the said embodiment as follows, for example.

  As shown in FIG. 5, when the cover 14 is assembled from above with the clip 40 mounted, the clip 40 may be pressed by the cover 14. In this case, the difference in wall height between the outer side of the case and the inner side of the case across the groove 31 in the peripheral wall portion 22 is matched with the thickness dimension of the connecting portion 42 of the clip 40, or the thickness dimension is slightly reduced. ing. Thereby, the position shift of the clip 40 can be suppressed reliably.

  -The structure of the element cooling function in the case main body 13 may be changed. For example, in FIG. 6, the refrigerant passage 23 is provided vertically in the peripheral wall portion 22. In FIG. 7, air cooling fins are provided on the peripheral wall portion 22 instead of providing the refrigerant passage 23. In addition, these heat radiating means may be formed by the assembly | attachment of another member other than being formed in the case main body 13 by one member.

  -The form of the clip 40 may be changed. For example, the pair of sandwiching portions 41 has an asymmetric shape. In this case, it is preferable to make the holding part 41 on the other side larger than the holding part 41 on the groove part 31 side of the pair of holding parts 41. Further, in this case, the contact portions in each clamping portion 41 are preferably provided so as to overlap at the same height position in the wall height direction and face each other in the wall thickness direction. In consideration of the fact that the heat radiation grease G is filled in the groove 31, the holding part 41 on the heat receiving part 32 side does not necessarily have to be in surface contact, and line contact or point contact with a smaller contact area than that. It may be.

  -The clip 40 may hold | grip the some semiconductor element 27 arrange | positioned side by side collectively. That is, as shown in FIG. 8, the width dimension of the clip 40 is made larger than the width dimension of the semiconductor element 27, and the plurality of semiconductor elements 27 and the heat receiving part 32 are sandwiched by the pair of clamping parts 41 of the clip 40. To do.

  The semiconductor element 27 to be cooled may not be mounted on the substrate, and may be mounted on the case body 13, for example.

  In the case body 13, a standing wall portion may be provided on the bottom portion 21 separately from the peripheral wall portion 22, and the standing wall portion may be used as the heat receiving portion 32. Further, the base member having the element cooling function may not be a case member (housing). For example, it may be a plate having no storage space.

  DESCRIPTION OF SYMBOLS 10 ... Power converter device, 13 ... Case main body (base member), 27 ... Semiconductor element, 32 ... Heat receiving part, 40 ... Clip (clip member), 41 ... Clamping part.

Claims (5)

An electric circuit device having a semiconductor element (27) that generates heat during operation,
Have a device cooling function, and the bottom (21) and the peripheral wall (22) bottomed box-shaped case member having a (13),
A lid member (14) attached to the distal end portion of the peripheral wall portion and closing the open portion of the case member;
A plate-shaped heat receiving portion (32) provided on the case member and having a heat receiving surface for contacting the outer surface of the semiconductor element;
A clip that holds the semiconductor element and the heat receiving portion between a pair of holding portions (41) while the outer surface of the semiconductor element and the heat receiving surface of the heat receiving portion are in contact with each other, and holds the contact state by elastic force A member (40);
Equipped with a,
In the peripheral wall portion, a groove portion (31) that opens to the tip side opposite to the bottom portion is formed, and the inner side of the case is the heat receiving portion than the groove portion,
The groove is filled with heat dissipation grease (G),
One of the pair of sandwiching portions in the clip member is arranged in the state of entering the heat dissipation grease in the groove portion, and the semiconductor element and the heat receiving portion are sandwiched by the clip member. Electrical circuit device to do. A circuit board (26) fixed to a position facing the bottom of the case member and mounted with the semiconductor element,
The semiconductor element is mounted vertically in the direction orthogonal to the substrate surface on the circuit board,
The electric circuit device according to claim 1 , wherein the clip member is mounted from a distal end side of the peripheral wall portion, and falling off is restricted by the lid member. The heat receiving part is for abutting the outer surfaces of a plurality of the semiconductor elements arranged side by side,
The groove, the plurality of semiconductor elements clip fixed electric circuit device according to claim 1 or 2 is formed into an elongated shape so as to be continuous in each position is. The electric circuit device according to any one of claims 1 to 3, wherein a wall height is larger on an outer side of the case and an inner side of the case with the groove portion interposed between the peripheral wall portions. The clip member is formed of a plate material having high thermal conductivity,
The pair of holding portions of the side of at least the semiconductor element of the clamping portion, the electric circuit device according to any one of claims 1 to 4 are in surface contact with the semiconductor element.

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