JP7124337B2 - Vehicle drive system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle drive system, and more particularly to a vehicle drive system including a rotating electrical machine and a housing that accommodates the rotating electrical machine.

2. Description of the Related Art Conventionally, an electric vehicle such as a hybrid car or an electric vehicle is provided with a vehicle driving device. A vehicle drive system is also called a transaxle. A vehicle drive device mounted on an electric vehicle includes a rotating electric machine that functions as a drive source or a generator of the electric vehicle, and a housing that accommodates the rotating electric machine.

A rotating electric machine may have a conductive portion such as a power line terminal or a coil end in which a conductor portion is exposed. In this case, if the housing of the vehicle drive device is damaged due to a collision of an electric vehicle or the like, the conductor member may enter the housing from the damaged portion of the housing and come into contact with the conductive portion of the rotating electric machine. As a result, a short circuit, a ground fault, or the like may occur in the conductive portion of the rotating electric machine, that is, the insulation of the conductive portion may be damaged.

2. Description of the Related Art Conventionally, there has been proposed a technique for ensuring insulation of a conductive portion of a rotating electric machine when a housing of a vehicle drive device is damaged. For example, in Patent Document 1, a side cover that is part of a housing and faces an axial end face of a rotating electric machine and a cover member that covers a coil end that is a conductive portion of the rotating electric machine is provided between the rotating electric machine and the rotating electric machine. A vehicle drive system is disclosed.

JP 2014-236575 A

When the housing of the vehicle drive system is damaged, fragments of the housing may scatter inside the housing. In particular, when the side cover facing the axial end portion of the rotating electrical machine where the conductive section of the rotating electrical machine is located is damaged, fragments of the side cover may scatter to the conductive section of the rotating electrical machine. If the side cover is formed of a conductor, there is a risk that the insulation of the conductive portion will be damaged by scattering pieces of the side cover onto the conductive portion of the rotating electric machine. If the insulation of the conductive portion is damaged, a problem may occur, for example, that electric discharge from the rotating electric machine cannot be performed.

Of course, it is possible to prevent fragments of the side cover from scattering to the conductive part by providing a cover member that covers the conductive part of the rotating electric machine inside the side cover, as in Patent Document 1, for example. It is desired to prevent fragments of the side cover from scattering to the conductive portion by a simple structure.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent fragments of a side cover from scattering to a conductive portion of a rotating electrical machine with a simpler structure when a side cover of a vehicle drive system is damaged.

The present invention provides a rotating electrical machine, a housing that accommodates the rotating electrical machine, the housing including a side cover facing an axial end face of the rotating electrical machine where a conductive portion of the rotating electrical machine is located, and an inner side of the side cover. and a protector attached to the surface of the rotating part, wherein the protector is positioned between the conductive part and a breakage prediction position on the side cover spaced apart from a position on the side cover facing the conductive part. A scattering prevention wall erected in an axial direction of an electric machine, comprising a scattering prevention wall for preventing fragments of the side cover from scattering to the conductive portion when the predicted breakage position is broken. A vehicle drive system.

If the predicted damage position is damaged, fragments of the side cover may scatter inside the housing (inside the side cover). According to the above configuration, when a fragment of the side cover scatters in a direction substantially perpendicular to the axial direction of the rotating electrical machine, the side cover is located between the expected breakage position and the conductive portion of the rotating electrical machine, and stands upright in the axial direction of the rotating electrical machine. The anti-scattering wall prevents fragments of the side cover from scattering from the expected breakage position to the conductive portion of the rotating electric machine.

According to the present invention, when the side cover of the vehicle drive device is damaged, it is possible to prevent fragments of the side cover from scattering to the conductive portion of the rotating electric machine with a simpler structure.

1 is a side view of the vehicle drive device according to the present embodiment with a side cover removed; FIG. 1 is a side view of the vehicle drive device according to the present embodiment with a side cover attached; FIG. It is a perspective view of a protector. FIG. 4 is a diagram showing a state in which the protector is attached to the inner surface of the side cover; FIG. 2 is a side view of the vehicle drive device according to the present embodiment with a side cover omitted;

FIG. 1 is a side view of a vehicle drive system 10 according to this embodiment. Originally, the side surface of the vehicle drive system 10 is covered with a side cover (see FIG. 2), but FIG. 1 shows the vehicle drive system 10 with the side cover removed.

The vehicle drive device 10 is mounted on an electric vehicle such as a hybrid car or an electric vehicle. The vehicle drive device 10 includes rotary electric machines MG1 and MG2 functioning as drive sources or generators of an electric vehicle, and a housing 12 that accommodates the rotary electric machines MG1 and MG2. In addition, the vehicle drive device 10 may include a power split mechanism or the like. In FIG. 1, the left side of the paper surface is the front of the electric vehicle, the upper side of the paper surface is the upper side of the electric vehicle, and the front side of the paper surface is the left side of the electric vehicle.

The housing 12 is made of a conductive rigid body such as metal. In this embodiment, the housing 12 is made of aluminum.

The rotary electric machines MG1 and MG2 are motor generators composed of rotors 14 and stators 16 . The stator 16 is formed by winding a coil around a cylindrical stator core, and the rotor 14 is a substantially cylindrical member arranged inside the cylinder of the cylindrical stator 16 . In the present embodiment, the rotary electric machines MG1 and MG2 are arranged in the housing 12 such that their axial directions coincide with the left-right direction of the electric vehicle. FIG. 1 shows axial end surfaces (left side surfaces) of the rotary electric machines MG1 and MG2.

A power line terminal 18 and a coil end 20 serving as conductive portions with exposed conductor portions are arranged on axial end surfaces (left side surfaces) of the rotary electric machines MG1 and MG2. The power line terminal 18 is a terminal to which a power line from the inverter is connected, and is a terminal through which electric power for driving the rotating electric machines MG1 and MG2 or electric power generated in the rotating electric machines MG1 and MG2 flows. Also, the coil end 20 is a portion of the coil wound around the stator core that protrudes in the axial direction.

FIG. 2 is a side view of the vehicle drive device 10 with the side cover 12a attached. The side cover 12a is part of the housing 12 and, as mentioned above, is made of aluminum in this embodiment. The side cover 12 a is attached to the left side surface of the vehicle drive device 10 .

As shown in FIG. 1, the power line terminal 18 and the coil end 20 serving as conductive portions are positioned on the axial end surfaces (left side surfaces) of the rotary electric machines MG1 and MG2. It is attached facing the axial end faces of the rotating electric machines MG1 and MG2 located. In FIG. 2, the positions of the axial end surfaces of the rotating electric machines MG1 and MG2 facing the side cover 12a are indicated by dashed lines.

On the side cover 12a, a predicted breakage position 30a that is highly likely to break due to a collision of an electric vehicle or the like is specified. The predicted damage position 30a may be an area within a certain range (an area where the possibility of damage is high). The predicted damage position 30a is specified in advance based on the results of crash tests or crash simulations of electric vehicles.

In the present embodiment, the predicted breakage position 30a is a position spaced apart from the position on the side cover 12a facing the conductive parts of the rotary electric machines MG1 and MG2. For example, FIG. 2 shows a position (area) 30b on the side cover 12a facing the power line terminal 18 of the rotary electric machine MG2, but the predicted breakage position 30a is a position spaced apart from the position 30b. there is Further, the predicted breakage position 30a includes a position on the side cover 12a facing the power line terminal 18 of the rotating electrical machine MG1, a position on the side cover 12a facing the coil end 20 of the rotating electrical machine MG1, and a coil end 20 of the rotating electrical machine MG2. is spaced apart from the position on the side cover 12a facing the .

A protector 40 is provided on the inner side of the side cover 12a, as indicated by a dashed line in FIG. The protector 40 has a function of preventing a conductive member entering from outside the housing 12 from coming into contact with the conductive portions of the rotating electrical machines MG1 and MG2 when the predicted breakage position 30a is damaged, and has a function of preventing fragments of the side cover 12a from contacting the rotating electrical machine MG1. , MG2 from scattering to the conductive portion.

A perspective view of the protector 40 is shown in FIG. The protector 40 is made of a rigid body such as metal, and is made of iron in this embodiment. Protector 40 includes a plate-like contact protection plate 42 . The contact protection plate 42 is provided with screw holes 44a and 44b for screwing and fixing to the inner surface of the side cover 12a. Furthermore, the protector 40 includes a scattering prevention wall 46 erected in a direction perpendicular to the contact protection plate 42 . In this embodiment, the anti-scattering wall 46 is erected at the end of the contact protection plate 42 . Further, in the present embodiment, a part of the anti-scattering wall 46 is cut away to form a cutout portion 48. This is because when the protector 40 is attached to the inner surface of the side cover 12a, the cutout portion 48 is formed. This is provided to avoid the raised portion formed on the inner surface of the cover 12a. In other words, when the protector 40 is attached to the side cover 12a, the raised portion on the inner surface of the side cover 12a is accommodated in the notch portion 48. As shown in FIG.

FIG. 4 shows the protector 40 attached to the inner surface of the side cover 12a. In FIG. 4, the right side of the paper surface is the front of the electric vehicle, the upper side of the paper surface is the upper side of the electric vehicle, and the back side of the paper surface is the left side of the electric vehicle.

The protector 40 is attached to the inner surface of the side cover 12a in a posture in which the anti-scattering wall 46 is erected in the axial direction of the rotary electric machines MG1 and MG2. Note that the concept that the scattering prevention wall 46 is erected in the axial direction of the rotating electric machines MG1 and MG2 can be applied only if the erecting direction of the scattering prevention wall 46 completely matches the axial direction of the rotating electric machines MG1 and MG2. However, it also includes a mode in which the erecting direction of the anti-scattering wall 46 is slightly deviated from the axial direction of the rotary electric machines MG1 and MG2. Specifically, when damage prediction position 30a is damaged, scattering prevention wall 46 can prevent fragments of side cover 12a from scattering to the conductive portions of rotating electric machines MG1 and MG2. The standing direction may deviate from the axial direction of the rotary electric machines MG1 and MG2.

In this embodiment, when the protector 40 is attached to the side cover 12a, the contact protection plate 42 is substantially parallel to the vertical plane. As described above, the anti-scattering wall 46 is erected in the direction orthogonal to the contact protection plate 42, so that when the protector 40 is attached to the side cover 12a, the anti-scattering wall 46 extends in the lateral direction of the electric vehicle. That is, they are erected in the axial direction of the rotary electric machines MG1 and MG2 (the direction orthogonal to the paper surface of FIG. 4). Specifically, the anti-scattering wall 46 is erected from the contact protection plate 42 toward the side cover 12a (left side, back side of the paper surface of FIG. 4).

In FIG. 4, the predicted damage position 30a is indicated by a one-dot chain line. The protector 40 is provided at a position where at least a portion of the predicted damage position 30a and at least a portion of the contact protection plate 42 of the protector 40 overlap when viewed from the side of the side cover 12a. As shown in FIG. 4, in the present embodiment, the contact protection plate 42 covers the entire area of the expected breakage position 30a in the side view of the side cover 12a.

In this embodiment, the protector 40 is attached to the inner surface of the side cover 12a. It may be fixed by other methods as long as it is provided in a standing posture.

FIG. 5 again shows a side view of the vehicle drive device 10 . Although illustration of the side cover 12a is omitted in FIG. 5, the predicted breakage position 30a on the side cover 12a and the protector 40 attached to the inner surface of the side cover 12a are illustrated. In FIG. 5 as well, the anti-scattering wall 46 is erected in a direction perpendicular to the plane of the paper (specifically, from the contact protection plate 42 toward the front of the plane of the paper).

As shown in FIG. 5, the anti-scattering wall 46 is erected between the predicted breakage position 30a and the conductive portions of the rotary electric machines MG1 and MG2. Specifically, the anti-scattering wall 46 is positioned between the predicted breakage position 30a and the power line terminal 18 of the rotary electric machine MG1. Moreover, the anti-scattering wall 46 is positioned between the predicted breakage position 30a and the coil end 20 of the rotary electric machine MG1. In addition, the anti-scattering wall 46 is positioned between the predicted breakage position 30a and the power line terminal 18 of the rotary electric machine MG2. In addition, the anti-scattering wall 46 is positioned between the predicted breakage position 30a and the coil end 20 of the rotary electric machine MG2.

Therefore, when the expected breakage position 30a is broken and fragments of the side cover 12a scatter inside the side cover 12a, especially inside the side cover 12a, they scatter in a direction substantially perpendicular to the axial direction of the rotating electric machines MG1 and MG2. In this case, the scattering prevention wall 46 prevents fragments of the side cover 12a from scattering to the conductive portions of the rotating electric machines MG1 and MG2. This prevents the insulation of the conductive portions of the rotating electric machines MG1 and MG2 from being damaged by the fragment of the side cover 12a when the predicted damage position 30a is damaged.

Further, in a side view of the side cover 12a, at least a portion of the contact protection plate 42 covers at least a portion of the predicted damage position 30a. Therefore, when the predicted damage position 30a is damaged, the conductor member ( For example, a front side member or the like) enters the housing 12, and the conductor member is prevented from coming into contact with the conductive portions of the rotating electric machines MG1 and MG2 (especially the coil end 20 of the rotating electric machine MG1 in the example of FIG. 5). This also prevents the insulation of the conductive portions of the rotating electric machines MG1 and MG2 from being damaged. Note that when the predicted damage position 30a is located at a position facing the conductive portions of the rotating electrical machines MG1 and MG2, the contact protection plate 42 prevents fragments of the side cover 12a from scattering to the conductive portions of the rotating electrical machines MG1 and MG2. be.

Although the embodiments according to the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the gist of the present invention.

For example, the vehicle drive device 10 according to the present embodiment has two rotating electrical machines MG1 and MG2, but the present invention can also be applied to a vehicle drive device having one rotating electrical machine.

10 Vehicle Drive Device 12 Housing 12a Side Cover 14 Rotor 16 Stator 18 Power Line Terminal 20 Coil End 30a Damage Predicted Position 30b Position 40 Protector 42 Contact Protection Plate 44a, 44b Screw Holes 46 anti-scattering wall, 48 notch, MG1, MG2 rotating electric machine.

Claims (1)

a rotating electric machine;
a housing that accommodates the rotating electrical machine, the housing including a side cover that faces an axial end surface of the rotating electrical machine in which a conductive portion of the rotating electrical machine is located;
a protector attached to the inner surface of the side cover;
with
The protector is
A scattering prevention wall erected in the axial direction of the rotating electrical machine between a breakage prediction position on the side cover spaced apart from a position on the side cover facing the conductive portion and the conductive portion, including a scattering prevention wall that prevents fragments of the side cover from scattering to the conductive portion when the predicted damage position is damaged;
A vehicle driving device characterized by:

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