JP6984398B2 - Power control unit - Google Patents

Description

The present invention relates to a power control unit that comprises a housing containing a power converter and is located within the engine compartment of the vehicle.

A power control in which two housings abutted against each other in the vertical direction of the vehicle are provided with a housing bolted at a plurality of fastening portions arranged on the outer peripheral portion, and a power conversion device is housed in the housing. The unit is known (Patent Document 1). This power control unit is located in the engine compartment of the vehicle.

Japanese Unexamined Patent Publication No. 2014-43124

In a housing as in Patent Document 1, when the impact load from the front of the vehicle is biased to one housing portion, the shear load is concentrated on the bolts of the fastening portion arranged on the side surface portion, and the bolts are sheared. There is a risk of destruction.

Therefore, an object of the present invention is to provide a power control unit capable of alleviating a shear load on a bolt of a fastening portion arranged on a side surface portion of a housing in the event of a vehicle front collision.

The power control unit according to one aspect of the present invention has a pair of side surface portions extending in the front-rear direction of the vehicle and four corner portions located at each end of the pair of side surface portions, and a housing for accommodating a power conversion device. In a power control unit having a body and arranged in an engine compartment of a vehicle, the housings are stacked in the vertical direction of the vehicle with the joint surfaces butted against each other, and are mounted on the four corner portions and the pair of side surface portions. It has a first housing portion and a second housing portion fastened by bolts at a plurality of arranged fastening portions, and at least one of the plurality of fastening portions is above and below the joint surface. A fastening portion that protrudes in the direction, a meshing portion that meshes with the protruding portion in a state where the joint surfaces are butted against each other to prevent the relative movement of the joint surfaces in the front-rear direction of the vehicle, and a fastening portion that contacts each other by fastening the bolts. A surface is provided, the protruding portion is provided so as to project in the vertical direction of the vehicle on the fastening surface, and the joint surface and the fastening surface are separated by a groove portion .

Top view of the power control unit according to one embodiment of the present invention. The figure which showed the state seen from the direction of arrow II of FIG. Top view showing the state of the lower part disassembled up and down with respect to the line III-III of FIG. An enlarged perspective view of a part of the state seen from the direction of arrow IV in FIG. 1. The figure which showed the effect of this embodiment together with the comparative example. The figure which showed the structure of the modification.

The power control unit (hereinafter referred to as PCU) 1 shown in FIGS. 1 and 2 is arranged in an engine compartment (not shown) in which a power source of a vehicle such as a hybrid vehicle or an electric vehicle is mounted. Used for power control of. The PCU 1 includes, for example, a housing 2 that houses a power conversion device (not shown) that functions as an inverter and a converter and is formed substantially in a rectangular shape. In FIG. 1 and other drawings, the arrow Fr indicates the front of the vehicle, the arrow Rr indicates the rear of the vehicle, the arrow R indicates the right side of the vehicle, the arrow L indicates the left side of the vehicle, the arrow U indicates the upper part of the vehicle, and the arrow D indicates the lower part of the vehicle. .. Since the housing 2 is formed substantially in a rectangular shape, it has a pair of side surface portions 2a extending in the front-rear direction of the vehicle and four corner portions 2b located at both ends of each side surface portion 2a.

As shown in FIG. 2, the housing 2 is located on the lower side in the vertical direction of the vehicle to accommodate the converter circuit, and is located on the upper side in the vertical direction of the vehicle to accommodate the inverter case 4. And have. As shown in FIG. 3, the converter case 3 and the inverter case 4 are opened in the vertical direction of the vehicle, respectively, and the joint surface 5 that goes around the upper opening of the converter case 3 and the lower part of the inverter case 4 are opened. The joint surfaces 6 that make a round of the opening are overlapped with each other in the vertical direction of the vehicle in a state of being butted against each other. Then, in a state where the joint surfaces 5 and 6 are butted against each other, they are fastened with seven bolts 9 as shown in FIG.

As shown in FIG. 2, the lower opening of the converter case 3 is closed by the lower cover 10, and the upper opening of the inverter case 4 is closed by the upper cover 11. The lower cover 10 and the upper cover 11 are fastened with a plurality of bolts 12. The housing 2 is arranged in the engine compartment by attaching the converter case 3 to the upper part of a transaxle (not shown). The transaxle is secured in the engine compartment to a vehicle body component (not shown). The converter case 3 corresponds to an example of the first housing portion of the above aspect, and the inverter case 4 corresponds to an example of the second housing portion of the above aspect.

In order to ensure the electromagnetic shielding property of the housing 2, each component of the housing 2 is made of a metal material. The converter case 3 and the inverter case 4 are made by casting an aluminum-based material, and the lower cover 10 and the upper cover 11 are made by pressing a steel plate material. Further, in order to ensure the sealing property of the housing 2, each component of the housing 2 is joined in a state where a foamed in-place gasket (FIPG), which is a kind of liquid sealing material, is applied to the joint surface. ..

As shown in FIG. 3, the fastening portions 15A to 15G to be fastened with the bolts 9 are arranged at each corner portion 2b of the housing 2, each side surface portion 2a, and the front portion 2c on the front side of the vehicle, respectively. There is. Hereinafter, when it is not necessary to distinguish the fastening portions 15A to 15G from each other, the fastening portions 15A to 15G may be referred to as a fastening portion 15. Each fastening portion 15 is configured such that a fastening surface 16 integrated with the bonding surface 5 of the converter case 3 and a fastening surface 17 integrated with the bonding surface 6 of the inverter case 4 are overlapped with each other. Although FIG. 3 shows the arrangement of the joint surface 5 and the fastening surface 16 of the converter case 3, the arrangement on the side of the inverter case 4 is the same as that of FIG.

Of the fastening portions 15E and fastening portions 15F arranged on the pair of side surface portions 2a, the fastening portion 15E on the right side of the vehicle is fastened to the fastening portion 15A and the fastening portion 15D, and the fastening portion 15F on the left side of the vehicle is fastened to the fastening portion 15B. It is arranged in the middle of the portion 15C. In each fastening portion 15, a bolt insertion hole 18 (see FIG. 1) into which a bolt 9 is inserted is formed on the inverter case 4 side, and a female screw 19 (see FIG. 3) that meshes with the bolt 9 is formed on the converter case 3 side. ing.

As shown in FIGS. 1 and 4, the fastening portion 15E on the right side of the vehicle protrudes from the fastening surface 16 on the converter case 3 side to the rear side of the vehicle with respect to the bolt 9 and protrudes upward from the joint surface 5 to the upper side of the vehicle. A portion 20 and a meshing portion 21 that meshes with the protruding portion 20 on the inverter case 4 side are provided. As shown in FIG. 4, the meshing portion 21 is configured to have a concave shape that retracts inward in the vehicle width direction so that the protruding portion 20 fits into the meshing portion 21 and opens outward in the vehicle width direction. By engaging the protruding portion 20 and the meshing portion 21, the relative movement of the joint surfaces 5 and 6 abutting each other in the vehicle front-rear direction is prevented.

(Effect of this form)
As shown in FIGS. 1 and 2, in the event of a vehicle front collision, the collision load F from the front of the vehicle is biased to the right side of the inverter case 4 of the PCU1 due to the arrangement of the PCU1 in the engine compartment and the arrangement of peripheral devices. To. When the collision load F is input, the load is concentrated on the right fastening portion 15E, which is a portion having higher rigidity than the others due to the structure of the housing 2. The load is distributed to the bolt 9 mounted on the fastening portion 15E and the protruding portion 20. Therefore, the shear load on the bolt 9 can be relaxed as compared with the form in which only the bolt is attached to the fastening portion without the protruding portion 20 and the meshing portion 21. Therefore, the load capacity of the PCU1 at the time of a vehicle front collision is improved.

FIG. 5 shows a change in the shear load acting on the bolt 9 mounted on the fastening portion 15E with respect to the impact load F together with a comparative example. In addition, the comparative example of FIG. 5 is an example in which the protruding portion 20 and the meshing portion 21 are omitted and only the bolt 9 is attached to the fastening portion 15E. As shown in FIG. 5, in the PCU1 of the present embodiment, a part of the shear load acting on the fastening portion 15E is borne by the protruding portion 20 and the meshing portion 21, so that the shear load acting on the bolt 9 is larger than that of the comparative example. It tends to decrease. Therefore, the load capacity Ls of the PCU1 that reaches the shear load capacity Ts of the bolt 9 is higher than that of the comparative example load capacity Ls'.

(Modification example)
Next, a modified example will be described with reference to FIG. This modification relates to the fastening portion 15E, and the joining surface 5 and the fastening surface 16 of the converter case 3 are separated by a groove portion 30 shown by hatching. The groove portion 30 is formed so as to recede from the joint surface 5 and the fastening surface 16. As described above, the joint surface 5 of the converter case 3 is abutted with the joint surface 6 (see FIG. 4) of the inverter case 4 in a state where the FIPG is applied. In the case of this modification, since the joint surface 5 and the joint surface 16 of the converter case 3 are separated by the groove portion 30, the FIPG applied to the joint surface 5 when the joint surface 5 and the joint surface 6 are butted against each other is formed. It is possible to prevent the FIPG from infiltrating up to the fastening surface 16 even if it protrudes to the outside. As a result, the fastening surface 16 on the converter case 3 side and the fastening surface 17 on the inverter case 4 side come into direct contact with each other to compensate for electrical conduction. Therefore, the fastening portion 15E according to this modification also functions as a metal touch portion.

In the above embodiment and the above modification, the converter case 3 and the inverter case 4 are fastened at seven fastening portions 15A to G, but this is only an example. For example, it changes the form of fastening at the fastening section 15A～15 F of six to omit the fastening portion 15G of the front of the vehicle. Also it includes a fastening portion 15A～15 F, can be further modified to add the form of two or more fastening portions. Further, it is possible to change to a form in which two fastening portions are arranged at each corner portion.

In the above embodiment, the joint surfaces 5 and 6 and the fastening surfaces 16 and 17 have the same height and are flat, respectively, which is an example. For example, it is possible to change to a form in which a height difference is provided between the joint surfaces 5 and 6 and the fastening surfaces 16 and 17.

In the above embodiment, the fastening portion 15E is provided with a protruding portion 20 on the converter case 3 side and a meshing portion 21 on the inverter case 4 side, which is an example. For example, these can be replaced so that the protrusion 20 is provided on the inverter case 4 side and the meshing portion 21 is provided on the converter case 3 side.

In the above embodiment, of the pair of side surface portions 2a, the protrusion 20 and the meshing portion 21 are provided on the right fastening portion 15E, which is an example. In the case of the PCU1, the collision load F tends to be input biased to the right side of the vehicle due to the relationship between the arrangement in the engine compartment and the peripheral devices (not shown) arranged around the PCU1, and the housing 2 In relation to the structure including the wall thickness and rigidity of the above, the load was concentrated on the right fastening portion 15E, and the load was the maximum as compared with the load acting on the other fastening portions 15A and the like. Therefore, in the above embodiment, the protrusion 20 and the meshing portion 21 are provided on the right fastening portion 15E.

For example, as a result of considering the arrangement of the PCU, the input position of the collision load at the time of a frontal collision, and the structure of the housing, if the place where the maximum load acting on the fastening portion at the time of a frontal collision of the vehicle is different from the above form, A protruding portion and a meshing portion can be provided at the relevant portion. Further, for example, when there are three or more fastening portions, protrusions and meshing portions are provided for each of the fastening portion having the second largest load and the fastening portion having the third largest load, and these are provided in the fastening portion having the maximum load. It is also possible to form a form in which the above is not provided. In this case, since the collision load is distributed by the fastening portion having the second largest load and the fastening portion having the third largest load, the load of the fastening portion on which the maximum load acts is relatively reduced, and the withstand load of the PCU is increased. improves.

In the above embodiment or the above modification, the protrusion 20 is integrally formed with the converter case 3 or the inverter case 4, which is an example. For example, a member such as a pin may be driven into a predetermined position of the converter case 3 or the inverter case 4, and the member may function as a protrusion.

The correspondence between the above-mentioned form and the above-mentioned modification and the above-mentioned embodiment is summarized as follows. That is, in the above embodiment and the above modification, the converter case 3 corresponds to an example of the first housing portion, and the inverter case 4 corresponds to an example of the second housing portion.

The embodiments of the present invention derived from each of the above-described embodiments and modifications are described below.

The power control unit according to one aspect of the present invention has a pair of side surface portions (2a) extending in the front-rear direction of the vehicle and four corner portions (2b) located at each end of the pair of side surface portions, and has electric power. In a power control unit (1) provided with a housing (2) for accommodating a conversion device and arranged in an engine compartment of a vehicle, the housing is placed up and down in a state where the joint surfaces (5, 6) are butted against each other. The first housing portion (3) and the second housing portion (3) which are overlapped in the direction and fastened with bolts (9) by a plurality of fastening portions (15A to 15F) arranged at the four corner portions and the pair of side surface portions. A housing portion (4) is provided, and at least one of the plurality of fastening portions has a protruding portion (20) protruding in the vertical direction of the vehicle from the joint surface and a state in which the joint surfaces are butted against each other. The meshing portion (21) is provided so as to mesh with the projecting portion and prevent the relative movement of the joint surfaces in the front-rear direction of the vehicle. In addition, although the reference code relating to the above-mentioned form is added in parentheses, it is not intended to be limited to each of the above-mentioned forms.

According to the power control unit of this aspect, when the collision load from the front of the vehicle is input to either the first housing portion or the second housing portion at the time of a collision in front of the vehicle, the bolts of the plurality of fastening portions are subjected to. Shear load acts on. Since at least one of the plurality of fastening portions is provided with a protruding portion and a meshing portion that meshes with the protruding portion, the load input to the fastening portion is distributed to the bolt and the protruding portion. Therefore, the shear load on the bolt can be relaxed as compared with the form in which only the bolt is attached to the fastening portion without the protruding portion and the meshing portion. Therefore, the load capacity of the power control unit at the time of a vehicle front collision is improved.

1 PCU
2 Housing 3 Converter case (1st housing)
4 Inverter case (second housing)
5, 6 Joint surface 9 Bolts 15A to 15F Fastening part 20 Protruding part 21 Engagement part

Claims (1)

It has a pair of side surfaces extending in the front-rear direction of the vehicle and four corners located at each end of the pair of side surfaces, has a housing for accommodating a power conversion device, and is arranged in the engine compartment of the vehicle. In the power control unit
The first housing is stacked in the vertical direction of the vehicle with the joint surfaces butted against each other, and is fastened with bolts at a plurality of fastening portions arranged at the four corner portions and the pair of side surface portions. It has a part and a second housing part,
At least one of the plurality of fastening portions includes a protruding portion that protrudes in the vertical direction of the vehicle from the joint surface and the joint surface that meshes with the protruding portion in a state where the joint surfaces are butted against each other in the vehicle front-rear direction. A meshing portion that prevents the relative movement of the bolt and a fastening surface that comes into contact with each other by fastening the bolts are provided, and the protruding portion is provided so as to project in the vertical direction of the vehicle on the fastening surface, and the joint surface is provided. A power control unit that is separated from the fastening surface by a groove.

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