JP2020152203A - Vehicle drive device - Google Patents

Abstract

To provide a vehicle drive device capable of cooling an oil seal separating an arrangement space of a liquid-cooled rotating electrical machine from an arrangement space of a dry clutch, with a simple configuration.SOLUTION: For a purpose of supplying to a side of an internal combustion engine E provided with an oil seal 40, a cooling liquid supplied from a side of a transmission T to a cylindrical rotary shaft 14 supporting a rotor Mr, a flow passage 41 is provided to supply the cooling liquid to the rotary shaft 14 of a rotary electric machine M from a side of an input shaft 16 of the transmission T. The rotary shaft 14 is provided with a shaft direction groove 44, a through hole 42 communicating the flow passage 41 with the shaft direction groove 44, and a radial direction groove 46 communicating the shaft direction groove 44 with an arrangement space of the rotary electric machine M.SELECTED DRAWING: Figure 1

Description

The present invention relates to a vehicle drive device including a drive shaft connected to an internal combustion engine, a liquid-cooled rotary electric machine, and a dry clutch capable of driving and connecting the drive shaft and the rotor of the rotary electric machine.

A vehicle drive device including a drive shaft connected to an internal combustion engine, a liquid-cooled rotary electric machine, and a wet clutch capable of driving and connecting the drive shaft and the rotor of the rotary electric machine. Is provided with an oil passage for supplying oil as a coolant (Patent Document 1).
In a vehicle drive device having such a configuration, if the clutch is changed to a dry type while the rotor of the rotary electric machine is liquid-cooled, the space where the rotary electric machine is arranged and the space where the dry clutch is arranged are arranged. It will be necessary to provide an oil seal that separates and.

Japanese Unexamined Patent Publication No. 2015-140044

In a vehicle drive device having the above configuration, the clutch (clutch plate) is usually arranged on the internal combustion engine side, so that the oil seal is also arranged on the internal combustion engine side. On the other hand, since the coolant for the rotary electric machine is supplied from the transmission side, the coolant may not be sufficiently supplied to the oil seal, and as a result, the oil seal may overheat.

The present invention has been devised in view of the above problems, and is for vehicles that can cool the oil seal that separates the space for arranging the liquid-cooled rotary electric machine and the space for arranging the dry clutch with a simple configuration. It is intended to provide a drive unit.

In order to achieve the above object, the vehicle drive device of the present invention includes a drive shaft connected to an internal combustion engine and a liquid-cooled rotary electric machine arranged on the outer peripheral side of the drive shaft in the radial direction. A dry clutch arranged between the drive shaft and the rotary electric machine and capable of driving and connecting the drive shaft and the rotor of the rotary electric machine, and a cylindrical rotary shaft (motor shaft) connected to the rotor. The input shaft of the transmission connected to the rotary shaft and the end of the rotary shaft on one end side on the internal combustion engine side are formed so as to project outward in the radial direction, and the rotor is brought into contact with the rotor for positioning. Oil that liquidally slides into a flange-shaped stop portion (flange) and the outer peripheral surface of the rotating shaft on one end side of the stop portion to partition the arrangement space of the rotary electric machine and the arrangement space of the dry clutch. A shaft is provided on the seal, a flow path for supplying cooling liquid from the input shaft side to the inner peripheral side of the other end side of the rotating shaft opposite to the internal combustion engine, and the outer peripheral surface of the rotating shaft. An axial groove for flowing a coolant extending from the other end in the direction to the end on the one end side, and the flow path and the axial groove penetrating the rotating shaft in and out. A through hole for communicating and a radial groove formed on the other end side surface of the stop portion and communicating the axial groove and the arrangement space of the rotary electric machine on the outer peripheral side of the stop portion are provided. It is characterized by being.

The flow path is formed by a gap between a wall portion of a cover member arranged on the other end side of the rotary electric machine and a partition wall portion arranged between the cover member and the dry clutch. Communicate between the supply port leading to the internal flow path of the input shaft and the through hole, and apply the cooling liquid in the flow path to the through hole on the inner peripheral side of the other end side of the rotating shaft. It is preferable that an annular wall portion for guiding the vehicle is provided.

On the outer peripheral surface of the rotating shaft, a key groove for connecting the rotating shaft and the rotor extends from the end on the other end side in the axial direction to the end on the one end side, and the axial groove extends. Is preferably provided in parallel with the keyway.
It is preferable that the axial groove and the key groove are arranged at equal intervals in the circumferential direction.
The end portion of the axial groove on the stop side is formed to be bent in the circumferential direction so as to approach the key groove, and the radial groove is arranged at a position close to the key groove. preferable.
It is also preferable that the axial groove is formed in a spiral shape.

According to the present invention, the coolant supplied from the input shaft side to the inner peripheral side of the other end side of the rotor rotation shaft opposite to the internal combustion engine through the flow path is supplied from the through hole to the rotation shaft. Since it flows into the outer peripheral surface of the rotary electric machine and further flows into the arrangement space of the rotary electric machine through the axial groove and the radial groove, the coolant flowing into the arrangement space of the rotary electric machine cools the heat generating part of the rotary electric machine and the rotary electric machine. It also cools the heat generating part of the oil seal (the sliding contact part of the rotating shaft that slides in contact with the oil seal) that divides the arrangement space. In addition, the coolant cools the rotating shaft as it flows through the axial groove. As a result, overheating of the oil seal and overheating of each part of the rotary electric machine are prevented.

It is a partial sectional view of the drive device for a vehicle which concerns on one Embodiment. It is a schematic diagram which shows the schematic structure of the drive device for a vehicle. It is a cross section of the rotation shaft (motor shaft) of the vehicle drive device. It is a side surface of the rotating shaft (motor shaft). It is a side surface which shows the 1st modification of the rotary shaft (motor shaft). It is a side surface which shows the 2nd modification of the rotating shaft (motor shaft). It is a partial cross-sectional view which shows the 1st modification of the 1st wall part and the 2nd wall part of the vehicle drive device which concerns on one Embodiment. It is a partial cross-sectional view which shows the 2nd modification of the 1st wall part and the 2nd wall part of the vehicle drive device which concerns on one Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
It should be noted that the embodiments shown below are merely examples, and there is no intention of excluding the application of various modifications and techniques not specified in the following embodiments.

〔Device configuration〕
As shown in FIG. 2, the vehicle drive device 10 according to the present embodiment includes an internal combustion engine E, a liquid-cooled rotary electric machine M, and a transmission T, and the rotary electric machine M is a motor or a motor generator. , The rotor Mr and the stator Ms are provided. Then, the drive shaft 12 connected to the internal combustion engine E is driven and connected to the hollow rotary shaft (motor shaft) 14 as a support member for supporting the rotor Mr of the rotary electric machine M via the dry clutch C so as to be decoupable. The rotating shaft 14 is connected to the input shaft 16 of the transmission T. Further, the output shaft 18 of the transmission T is connected to the drive wheels 20, and between the input shaft 16 and the output shaft 18, a belt-type continuously variable transmission mechanism (not shown), a planetary gear-type stepped transmission mechanism, or the like is used. A well-known transmission mechanism is provided. In the case of the belt type continuously variable transmission mechanism, the connection state with the rotary electric machine M is controlled by controlling the engagement / release of the forward / backward clutch, and in the case of the planetary gear type stepped transmission mechanism, the engagement / release in the mechanism. The connection state with the rotary electric machine M is controlled by the control of.

As shown in FIG. 1, the rotary electric machine M is arranged on the outer peripheral side (diameterally outward) of the drive shaft 12, and a dry clutch C is provided between the drive shaft 12 and the rotary electric machine M in the radial direction. It is arranged. In FIG. 1, the axis CL of the drive shaft 12 and the input shaft 16 is indicated by a single point chain line, and the arrow E indicates the internal combustion engine E side (one end side) with respect to the axial direction (direction of the axis CL). , Arrow T indicates the transmission T side (the other end side) in the axial direction.
The structure of the dry clutch C is well known and details are not shown, but the dry clutch C has a plurality of clutch plates 22 arranged on the internal combustion engine E side (one end side) and a transmission T side (the other end). It is provided on the side) with a hydraulically actuated piston 24 capable of pressing the clutch plate 22. The piston 24 is provided with a plurality of push rods 24a at intervals in the circumferential direction, and the push rods 24a penetrate the holes 32a provided in the radial connecting portion 32 described later and press the clutch plate 22. It is composed. The piston 24 is provided with an oil chamber (not shown) that applies hydraulic pressure to press the clutch plate 22, and a return spring 23 that urges the clutch plate 22 in the direction opposite to the hydraulic pressure.

The rotating shaft 14 is formed in a cylindrical shape, and the rotor Mr is supported on the outer peripheral surface thereof, and a flange-shaped stopping portion 26 is provided on the internal combustion engine E side (one end side) so as to project outward in the radial direction. Then, the end plate 30 on the internal combustion engine E side of the rotor Mr comes into contact with the end surface 28 on the transmission T side of the stop portion 26, so that the axial position of the rotor Mr is positioned.
Further, on the inner peripheral side of the rotating shaft 14, a flange-shaped radial connecting portion 32 for connecting the rotating shaft 14 to the input shaft 16 is integrally formed.

In the rotary electric machine M and the dry clutch C, the internal combustion engine E side (one end side) is covered with the first cover member 50, and the transmission T side (the other end side) and the outer peripheral side are covered with the second cover member 51. .. Further, the radial connecting portion 32 is surrounded by the first cover member 50 and the second cover member 51, and the space on the axis side of the rotating shaft 14 is changed to the space S1 on the internal combustion engine E side (one end side). It also functions as a partition wall portion that separates the space S2 on the machine T side (the other end side). The dry clutch C is provided in the space S1 on the internal combustion engine E side partitioned by the radial connecting portion 32 as the partition wall portion.

The push rod 24a of the piston 24 penetrates the hole 32a provided in the radial connecting portion 32 and presses the clutch plate 22, but a diaphragm 60 is arranged around one end side of the hole 32a and pushes. The tip of the rod 24a presses the clutch plate 22 via the diaphragm 60. Therefore, the space S1 on the internal combustion engine E side (one end side) and the space S2 on the transmission T side (the other end side) of the radial connection portion 32 are liquid-tightly partitioned by the radial connection portion 32 and the diaphragm 60. There is.

In the liquid-cooled rotary electric machine M, from the supply port 34 provided on the input shaft 16, as shown by the arrow A of the one-point chain line, the piston 24, the radial connecting portion 32, and the inner peripheral surface of the rotating shaft 14 are connected. The coolant (hydraulic oil of the transmission T) is supplied from the transmission T side through the space.

That is, the input shaft 16 is formed with an in-axis flow path 33 at the axial center portion thereof, and a supply port 34 is formed so as to communicate with the in-axis flow path 33 and the outer circumference of the input shaft 16. The hydraulic oil as the coolant is supplied from the transmission T side to the in-shaft flow path 33, and is supplied from the supply port 34 into the space S2 on the internal combustion engine E side (one end side) of the radial connection portion 32.
In the space S2, a flow path 41 is formed by a gap between the wall portion 51a of the second cover member 51 and the radial connecting portion (partition wall portion) 32.

On the other hand, on the internal combustion engine E side of the stop portion 26, the arrangement space 36 (space S1) of the dry clutch C (clutch plate 22) and the arrangement space 38 of the rotary electric machine M are in close sliding contact with the outer peripheral surface of the rotary shaft 14. An oil seal 40 for partitioning and is provided.

An axial groove 44 for flowing a coolant extends from the end on the other end side in the axial direction to the end on the one end side on the outer peripheral surface of the rotating shaft 14. Further, a through hole 42 is formed which penetrates the rotating shaft 14 in and out and communicates the flow path 41 and the axial groove 44.
Further, a radial groove 46 is formed on the end surface 28 of the flange-shaped stop portion 26 on the transmission T side to communicate the axial groove 44 and the arrangement space 38 of the rotary electric machine on the outer peripheral side of the stop portion 26. ..

Further, on the inner peripheral side of the other end side of the rotating shaft 14, the coolant in the flow path 41 is suppressed from flowing out from the inner peripheral space of the rotating shaft 14 to the further other end side of the rotating shaft 14. An annular wall portion (blocking ring) 43 for guiding the coolant in the flow path 41 to the through hole 42 is provided.

Therefore, the coolant supplied from the supply port 34 into the space S2 on the internal combustion engine E side (one end side) of the radial connecting portion 32 is the flow path 41, the through hole 42, and the axial direction as shown by the arrow A. It is supplied to the arrangement space 38 of the rotary electric machine on the outer peripheral side of the stop portion 26 via the groove 44 and the radial groove 46.

In the present embodiment, as shown in FIGS. 3 and 4, a key groove 62 for connecting the rotating shaft 14 and the rotor Mr is formed on the outer peripheral surface of the rotating shaft 14 from one end on the other end side in the axial direction. It extends to the end on the side. The key groove 62 is formed with substantially the same width and depth as the axial groove 44, but the through hole 42 and the radial groove 46 are not formed at the end of the key groove 62.
Further, two key grooves 62 are formed on the outer peripheral surface of the rotating shaft 14 at equal intervals (180 ° intervals) in the circumferential direction.

On the other hand, a plurality of axial grooves 44 (three in this case) are formed at equal intervals (45 ° intervals) in the circumferential direction between the two key grooves 62 on the outer peripheral surface of the rotating shaft 14.
Further, in the present embodiment, each axial groove 44 is formed so as to be oriented on a straight line parallel to the axial direction on the outer peripheral surface of the rotating shaft 14, similarly to the key groove 62.

Further, the end plate 30 is formed with an annular first wall portion 48 projecting in the axial direction so that its inner peripheral surface faces the opening 46a on the outer peripheral side of the radial groove 46, and the rotary electric machine M and the dry type On the inner surface side of the cover member 50 that covers the internal combustion engine E side of the clutch C, an annular second wall portion 52 corresponding to the first wall portion 48 is formed so as to project axially toward the rotor Mr side. Then, the tip surface 54 of the first wall portion 48 and the tip surface 56 of the second wall portion 52 face each other to narrow the width of the gap 58 formed between the two tip surfaces 54 and 56, and the distribution area is reduced. The amount of coolant flowing from the inner peripheral side to the outer peripheral side of both wall portions 48 and 52 is reduced.
Further, the base portion 40b of the oil seal 40 is fixed to the inner peripheral surface of the second wall portion 52.

[Action and effect]
According to the drive device for the present vehicle having the above configuration, the coolant for the rotary electric machine M supplied to the transmission T side passes through the in-shaft flow path 33 and the supply port 34 of the input shaft 16, and the flow path 41, It is supplied to the internal combustion engine E side through the through hole 42, the axial groove 44, and the radial groove 46, and the vicinity of the stop portion 26 of the rotating shaft 14 is cooled. Therefore, the heat generating portion (oil) by the oil seal 40 is provided accordingly. The sliding contact portion of the rotating shaft 14 that is in sliding contact with the seal 40) is also cooled.

When the coolant in the flow path 41 approaches the vicinity of the through hole 42, it tries to flow out from the inner peripheral space of the rotating shaft 14 to the other end side of the rotating shaft 14, but on the inner circumference of the rotating shaft 14. Since the provided annular wall portion 43 suppresses the outflow of the rotating shaft 14 to the other end side and guides the coolant in the flow path 41 to the through hole 42, the coolant is efficiently supplied to the vicinity of the stop portion 26. Will be done.
Of course, a part of the coolant flows over the annular wall portion 43 and flows out to the other end side of the rotary shaft 14 and enters the arrangement space 38 of the rotary electric machine M, and the rotor Mr and the stator Ms of the rotary electric machine M Is cooled from the other end side.

Further, the cooling liquid flowing out from the opening 46a of the radial groove 46 is changed in the flow direction toward the oil seal 40 by the inner peripheral surface of the first wall portion 48, and the flow area of the gap 58 is reduced. Since the outflow of the coolant to the outside of the walls 48 and 52 is reduced, the amount of the coolant supplied to the oil seal 40 can be increased, and the oil seal 40 can be cooled efficiently.
Further, since the second wall portion 52 is also used as the fixing structure of the oil seal 40, it is possible to prevent the structure from becoming complicated.
Of course, a part of the coolant enters the arrangement space 38 of the rotary electric machine M from the gap 58 and cools the rotor Mr and the stator Ms of the rotary electric machine M from one end side.

In this way, overheating of the oil seal 40 and overheating of each part of the rotary electric machine M are prevented.
In the present embodiment, since a plurality of axial grooves 44 and radial grooves 46 are provided, the rotating shaft 14 can be efficiently cooled.
Further, since the axial grooves 44 and the key grooves 62 are formed at equal intervals in the circumferential direction, a decrease in strength of the rotating shaft 14 due to grooving is suppressed.

[Modification example 1 of axial groove]
In the above embodiment, the axial groove 44 is formed so as to be oriented on a straight line parallel to the axial direction on the outer peripheral surface of the rotating shaft 14, but as shown in FIG. 5, the axial groove 44A rotates. It may be formed in a spiral shape that swirls around the axis on the outer peripheral surface of the shaft 14. When there is a keyway 62, the magnitude of the spiral turning angle with respect to the amount of movement in the axial direction is restricted and limited to a spiral with a slight turning angle, but the rotating shaft 14 can be cooled evenly in the circumferential direction. it can.

[Modification example 2 of axial groove]
Further, as shown in FIG. 6, a bent portion 44C formed by bending in the circumferential direction so as to approach the key groove 62 is provided at the end of the axial groove 44B on the stop portion 26 side, and the radial groove 46 is keyed. It is also preferable to arrange it at a position close to the groove 62.
With such a configuration, the key groove 62, which tends to overheat, can be cooled more positively and overheating can be suppressed.

[Modification of the first wall and the second wall]
7 and 8 show different configurations (first modification, second modification) of the corresponding first wall portion 48 and second wall portion 52, and the first modification shown in FIG. 7 is The first wall portion 48 is extended to the outer peripheral side of the second wall portion 52 so that both wall portions 48 and 52 overlap in the radial direction, and the inner peripheral surface of the first wall portion 48 and the outer peripheral surface of the second wall portion 52 A gap 58 is formed at.
According to this configuration, the flow direction of the coolant flowing out of both walls 48 and 52 is changed from the radial direction to the axial direction, so that the flow resistance is increased and the outflow of the coolant is further reduced. it can.

In the second modification shown in FIG. 8, the first step portion 48s is formed at the tip end portion of the first wall portion 48, the second step portion 52s is formed at the tip end portion of the second wall portion 52, and both step portions are formed. The 48s and 52s were configured to overlap each other with a gap 58'. With this configuration, the gap 58'becomes a so-called labyrinth shape, the flow resistance is further increased, and the outflow of the coolant can be further reduced.

[Other]
Although the embodiments of the present invention have been described above, it goes without saying that the present invention can be appropriately modified and implemented.
For example, in the above embodiment, two key grooves 62 are provided on the outer peripheral surface of the rotating shaft 14, and three axial grooves 44 are provided between the key grooves 62, but the number of each groove is limited to this. It may be more or less than this.
Further, it is preferable that the key grooves 62 and the axial grooves 44 are arranged at equal intervals in the circumferential direction in terms of strength, but the intervals in the circumferential direction can be appropriately set.
When the cooling liquid in the flow path 41 can smoothly enter the inside of the through hole 42 due to the shape of the inner wall of the space S2 or the like, the annular wall portion (part blocking ring) 43 can be omitted.

10 Vehicle drive device 12 Drive shaft 14 Rotating shaft (support member)
16 Input shaft 26 Stop 30 End plate 32 Radial connection (partition wall)
36 Arrangement space for dry clutch C 38 Arrangement space for rotary electric machine M 40 Oil seal 41 Flow path 42 Through hole 43 Circular wall part (part blocking ring)
44, 44A, 44B Axial groove 44C Bending part 46 Radial groove 46a Opening 48 First wall part 52 Second wall part 58, 58'Gap 62 Key groove

Claims (6)

The drive shaft connected to the internal combustion engine and
A liquid-cooled rotary electric machine arranged on the outer peripheral side of the drive shaft,
A dry clutch that is arranged between the drive shaft and the rotary electric machine in the radial direction and can drive and connect the drive shaft and the rotor of the rotary electric machine.
A cylindrical rotating shaft connected to the rotor,
The input shaft of the transmission connected to the rotating shaft and
A flange-shaped stop portion formed so as to project outward in the radial direction at one end of the rotating shaft on the internal combustion engine side, and for abutting and positioning the rotor.
An oil seal that is liquid-tightly slidably contacted with the outer peripheral surface of the rotating shaft on one end side of the stop portion to partition the space for arranging the rotary electric machine and the space for arranging the dry clutch.
A flow path for supplying the cooling liquid from the input shaft side to the inner peripheral side of the other end side of the rotating shaft opposite to the internal combustion engine.
On the outer peripheral surface of the rotating shaft, an axial groove for flowing a coolant extending from the end on the other end side in the axial direction to the end on the one end side,
A through hole that penetrates the rotating shaft in and out and communicates the flow path and the axial groove.
It is characterized by having a radial groove formed on the other end side surface of the stop portion and communicating the axial groove and the arrangement space of the rotary electric machine on the outer peripheral side of the stop portion. Vehicle drive device. The flow path is formed by a gap between a wall portion of a cover member arranged on the other end side of the rotary electric machine and a partition wall portion arranged between the cover member and the dry clutch. Communicate between the supply port leading to the internal flow path of the input shaft and the through hole,
The first aspect of the present invention, wherein an annular wall portion for guiding the cooling liquid in the flow path to the through hole is provided on the inner peripheral side of the other end side of the rotating shaft. Vehicle drive device. On the outer peripheral surface of the rotating shaft, a key groove for connecting the rotating shaft and the rotor is extended from the end on the other end side in the axial direction to the end on the one end side.
The vehicle drive device according to claim 1 or 2, wherein a plurality of the axial grooves are provided in parallel with the key grooves. The vehicle drive device according to claim 3, wherein the axial grooves and the key grooves are arranged at equal intervals in the circumferential direction. The end portion of the axial groove on the stop side is formed to be bent in the circumferential direction so as to approach the key groove, and the radial groove is arranged at a position close to the key groove. The vehicle drive device according to claim 3 or 4. The vehicle drive device according to any one of claims 1 to 5, wherein the axial groove is formed in a spiral shape.

Images