JP2018101690A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology that uniformly applies a load to a cooler at an end of a lamination unit in an electronic device including the lamination unit of coolers and semiconductor modules.SOLUTION: A lamination unit 10 is housed between an inner wall 21b and support pillars 22 of a housing 21 of an electric power conversion system 20. A leaf spring 23 is sandwiched between a cooler 3a at one end of the lamination unit 10 in a lamination direction and the support pillars 22 opposing the cooler 3a. The leaf spring 23 applies a load to the lamination unit 10 in the lamination direction. A spacer 24 is sandwiched between the lamination unit 10 and the leaf spring 23. The leaf spring 23 is curved when viewed in a direction perpendicular to the lamination direction, contacts with the support pillars 22 at both ends 23b, and contacts with the spacer 24 at a center part 23a. Flexural strength of the spacer 24 around a straight line extending in a Z axis direction is larger than flexural strength of the cooler 3a.SELECTED DRAWING: Figure 2

Description

  The technology disclosed in this specification relates to an electronic device. In particular, the present invention relates to an electronic apparatus including a stacked unit in which a plurality of coolers are arranged in parallel and a semiconductor module is sandwiched between adjacent coolers.

  Patent Documents 1-3 disclose an electronic device including the above-described laminated unit. Any of the electronic devices is a power conversion device that is mounted on an electric vehicle and converts battery power into driving power for a driving motor. Each semiconductor module is sealed with a power conversion power transistor. A power transistor generates a large amount of heat. The above-described laminated unit can cool the card type semiconductor module from both sides, and can effectively cool the power transistor.

  The stacked unit is accommodated between a pair of support portions provided in the casing of the electronic device. The support part is a column extending from the floor of the casing or a wall of the casing. A leaf spring is sandwiched between the stacked unit and one of the support portions, and the leaf spring loads the stacked unit in the stacking direction (the stacking direction of the cooler and the semiconductor module). The adjacent cooler and the semiconductor module are brought into close contact with each other by the load of the leaf spring, and the movement of heat from the semiconductor module to the cooler is promoted.

  In the electronic devices of Patent Documents 1 and 2, a spacer is sandwiched between one support portion of the housing and the leaf spring. The spacer is provided to adjust the size of the space in which the leaf spring is accommodated. That is, the spacer is provided for adjusting the load applied by the leaf spring to the laminated unit. In the electronic device of Patent Document 3, a contact plate is sandwiched between a leaf spring and a laminated unit.

JP2013-162541A Japanese Patent Laid-Open No. 2006-029693 JP 2009-094257 A

  The leaf spring is curved when viewed from the direction perpendicular to both the stacking direction of the stacked unit and the longitudinal direction of the cooler, and both ends thereof are in contact with one support portion and the central portion is in contact with the stacked unit. . On the other hand, the inside of the cooler is a refrigerant flow path, and the bending rigidity is not high. If the central portion of the leaf spring locally contacts the end face of the cooler at the end of the stacked unit, the cooler may be deformed. The present specification provides a technique in which a load is uniformly applied to the cooler at the end of the laminated unit.

  The electronic device disclosed in this specification includes a laminated unit, a housing, a leaf spring, and a spacer. A stacked unit is a device in which a plurality of coolers are arranged in parallel and a semiconductor module is sandwiched between adjacent coolers. The housing is provided with a pair of support portions, and the stacked unit is accommodated between the pair of support portions. The leaf spring is sandwiched between a cooler at one end in the stacking direction of the stacked unit and one support portion facing the cooler, and loads the stacked unit in the stacking direction. The spacer is sandwiched between the laminated unit and the leaf spring. The leaf spring is curved when viewed from a direction (orthogonal direction) perpendicular to both the longitudinal direction and the stacking direction of the cooler, and both ends thereof are in contact with one support portion and the center portion is in contact with the spacer. It touches. The bending rigidity around the straight line extending in the orthogonal direction of the spacer is larger than the bending rigidity of the cooler. In this electronic device, the load of the leaf spring is received by a highly rigid spacer, and the spacer applies a uniform load to the adjacent cooler. By providing the spacer having high rigidity, the cooler at the end of the laminated unit is uniformly loaded. Details and further improvements of the technology disclosed in this specification will be described in the following “DETAILED DESCRIPTION”.

It is a perspective view of a lamination | stacking unit. It is a top view of a power converter device. It is sectional drawing of the range which the broken line III of FIG. 2 shows.

  An electronic apparatus according to an embodiment will be described with reference to the drawings. The electronic device according to the embodiment is a power conversion device that is mounted on an electric vehicle and converts battery power into driving power for a travel motor. The power conversion device includes a plurality of power conversion power transistors. A plurality of power transistors are housed in the semiconductor module two by two. The plurality of semiconductor modules is a card type, and a plurality of coolers and one by one are alternately stacked to constitute a stacked unit.

  FIG. 1 is a perspective view of the laminated unit 10. The stacked unit 10 is a unit in which a plurality of flat plate type coolers 3 are arranged in parallel and the semiconductor module 2 is sandwiched between adjacent coolers 3. In FIG. 1, to help understanding, one semiconductor module 2 is drawn from the stacked unit 10.

  The X axis of the coordinate system in the figure corresponds to the stacking direction of the cooler 3 and the semiconductor module 2. The cooler 3 is flat and elongated, and the Y axis corresponds to the longitudinal direction of the cooler 3.

  The main body of the semiconductor module 2 is made of resin, and two power transistors Ta and Tb and two diodes Da and Db are sealed in the main body. The two power transistors Ta and Tb are connected in series inside the main body. The respective diodes Da, Db are connected in antiparallel to the respective power transistors Ta, Tb. Three power terminals 2 a, 2 b, 2 c extend from one narrow surface of the semiconductor module 2. The power terminals 2a, 2b, and 2c are respectively connected to the high potential side, the low potential side, and the midpoint of the serial connection of the power transistors Ta and Tb inside the main body of the semiconductor module 2. A plurality of control terminals 2 d extend from another narrow surface of the semiconductor module 2. The control terminal 2d is a gate terminal connected to the gate of each power transistor, a terminal connected to a sense emitter for measuring a current flowing through each power transistor, or a temperature sensor built in the semiconductor module 2. Such as a terminal connected to.

  The plurality of coolers 3 are flat and have an elongated shape, and the inside thereof is a cavity. The cavity serves as a refrigerant flow path through which liquid refrigerant flows. The adjacent coolers 3 with the semiconductor module 2 interposed therebetween are connected by two connecting pipes 5a and 5b. In FIG. 1, reference numerals 5 a and 5 b are attached only to the leftmost connecting pipe, and the reference numerals of the other connecting pipes are omitted. The two connecting pipes 5 a and 5 b are positioned so as to sandwich the semiconductor module 2 in the longitudinal direction (Y direction) of the elongated cooler 3.

  A refrigerant supply pipe 4a and a refrigerant discharge pipe 4b are connected to the cooler 3 at one end in the stacking direction of the stacking unit 10 (the cooler 3 at the left end in FIG. 1). The refrigerant supply pipe 4a is disposed so as to overlap one of the pair of connecting pipes 5a and 5b (connecting pipe 5a) when the stacked unit 10 is viewed along the stacking direction. The refrigerant discharge pipe 4b is disposed so as to overlap the other of the pair of connecting pipes 5a and 5b (connecting pipe 5b) when the stacked unit 10 is viewed along the stacking direction. The refrigerant supply pipe 4a and the refrigerant discharge pipe 4b are connected to a refrigerant circulator (not shown). A liquid refrigerant is supplied from the refrigerant circulator to the stacking unit 10 through the refrigerant supply pipe 4a. The refrigerant is distributed to all the coolers 3 through one connecting pipe 5a. The refrigerant absorbs the heat of the adjacent semiconductor module 2 while passing through the inside of the cooler 3. The refrigerant that has absorbed heat is discharged from the laminated unit 10 through the other connecting pipe 5b and the refrigerant discharge pipe 4b. The discharged refrigerant returns to the refrigerant circulator, and is discharged to the stacking unit 10 again after the heat is released and the temperature is lowered. The refrigerant is water or LLC (Long Life Coolant).

  Although illustration is omitted, an insulating plate is sandwiched between the semiconductor module 2 and the cooler 3. The insulating plate may be regarded as a part of the semiconductor module 2 or may be regarded as a part of the cooler 3.

  The top view of the power converter device 20 is shown in FIG. FIG. 2 is a top view of the housing 21 with the upper cover removed. FIG. 2 schematically illustrates the inside of the housing 21 that houses the laminated unit 10, and other components of the power conversion device 20 are not illustrated. In FIG. 2, for easy understanding, the semiconductor module 2 is shaded in light gray, and the spacer 24 described later is shaded in dark gray. Further, among the plurality of coolers 3 included in the stacked unit 10, reference numerals 3a and 3b are used to distinguish the cooler at the end in the stacking direction from other coolers. In FIG. 2 and FIG. 3 described later, the insulating plate sandwiched between the cooler 3 and the semiconductor module 2 is not shown.

  The laminated unit 10 is accommodated between two support columns 22 provided on the housing 21 and the inner wall 21b. The support column 22 is erected on the floor surface 21 a of the housing 21. The inner wall 21b is a part where a part of the side wall around the casing 21 is thickened.

  The stacked unit 10 is arranged such that the cooler 3a at one end in the stacking direction of the cooler 3 and the semiconductor module 2 faces the support column 22, and the cooler 3b at the other end in the stacking direction faces the inner wall 21b. The cooler 3b is in direct contact with the inner wall 21b. The refrigerant supply pipe 4 a and the refrigerant discharge pipe 4 b connected to the cooler 3 b penetrate the side wall of the housing 21 and extend to the outside of the housing 21.

  A leaf spring 23 and a spacer 24 are sandwiched between the cooler 3 a at one end of the laminated unit 10 and the column 22. The spacer 24 is arrange | positioned so that the surface facing the support | pillar 22 of the cooler 3a may be contact | connected. The leaf spring 23 is disposed between the support column 22 and the spacer 24. The leaf spring 23 is curved as viewed from the Z direction in the figure, and both ends 23 b thereof are in contact with the support column 22, and the central portion 23 a is in contact with the spacer 24. The leaf spring 23 loads the stacked unit 10 in the stacking direction, and improves the adhesion between the adjacent semiconductor module 2 and the cooler 3. When the adhesion between the semiconductor module 2 and the cooler 3 is increased, the semiconductor module 2 is effectively cooled. The Z direction in the figure corresponds to a direction orthogonal to both the stacking direction of the stacking unit 10 and the longitudinal direction of the cooler 3.

  FIG. 3 is a cross-sectional view in which the portion surrounded by the broken line III in FIG. 2 is cut along the XY plane in the drawing. In FIG. 3, the internal structure of the semiconductor module 2 is omitted, and only a cross section of the resin main body is shown. The cooler 3 is obtained by welding two side plates 31 and 32 having flanges at their flange surfaces. The side plates 31 and 32 are made of aluminum. The inside of the cooler 3 is hollow, and the refrigerant introduced through one connecting pipe 5a passes through the inside and is discharged through the other connecting pipe 5b. A thick arrow line A in the figure indicates the flow of the refrigerant. The cooler 3 is formed by bonding two aluminum side plates 31 and 32, and the bending rigidity against out-of-plane deformation is not high. Here, the out-of-plane rigidity is a direction (Z in the figure) orthogonal to both the laminating direction (X direction in the figure) of the laminated unit 10 and the longitudinal direction (Y direction in the figure) of the elongated cooler 3. Direction). In other words, the cooler 3 does not have high bending rigidity around a straight line extending in a direction (Z direction in the drawing) orthogonal to both the stacking direction of the stacking unit 10 and the longitudinal direction of the cooler 3.

  On the other hand, the spacer 24 is made of a thick iron plate, and is bent around a straight line extending in a direction (Z direction in the drawing) orthogonal to both the stacking direction of the stacking unit 10 and the longitudinal direction of the cooler 3. The rigidity is higher than that of the cooler 3. Therefore, even if the leaf spring 23 applies a load to the spacer 24 only at the central portion 23a, the spacer 24 hardly deforms. The spacer 24 receives a load locally from the leaf spring 23 through the central portion 23a, but is hardly deformed by the load and uniformly loads the adjacent coolers 3a. By this highly rigid spacer 24, the cooler 3a at the end of the laminated unit 10 can receive a uniform load.

  Points to be noted regarding the embodiment will be described. The support column 22 and the inner wall 21b correspond to a pair of support portions in which the stacked unit 10 is accommodated therebetween. The technology disclosed in the present specification may be applied to an electronic device other than the power conversion device as long as it is an electronic device including a stacked unit.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Semiconductor modules 2a, 2b, 2c: Power terminal 2d: Control terminals 3, 3a, 3b: Cooler 4a: Refrigerant supply pipe 4b: Refrigerant discharge pipe 5a, 5b: Connecting pipe 10: Laminate unit 20: Power converter 21 : Housing 21a: Floor surface 21b: Inner wall 22: Strut 23: Leaf spring 23a: Central portion 23b: Both ends 24: Spacer 31, 32: Side plate 32: Side plate Da, Db: Diode Ta, Tb: Power transistor

Claims (1)

A stacked unit in which a plurality of coolers are arranged in parallel and a semiconductor module is sandwiched between adjacent coolers;
A housing that is provided with a pair of support portions, and that houses the stacked unit between the pair of support portions;
A leaf spring that is sandwiched between the cooler at one end in the stacking direction of the stacking unit and the one support portion facing the cooler, and loads the stacking unit in the stacking direction;
A spacer sandwiched between the laminated unit and the leaf spring;
With
The leaf spring is curved as viewed from the direction orthogonal to both the longitudinal direction of the cooler and the stacking direction, and both ends thereof are in contact with one of the support portions, and the central portion is the spacer. Abut,
An electronic apparatus, wherein a bending rigidity of the spacer around a straight line extending in the orthogonal direction is larger than a bending rigidity of the cooler.

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