JP2012162223A - Power transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission device that maintains the initial performance for a long period of time while having a small physical constitution.SOLUTION: A clutch 50 has: a drum 51 having a cylindrical part 511 in which at least a part in the axial direction is located in a storage space 35 and which is connected to an output shaft 112 of an engine 11; a frictional-engagement element 52 provided so as to be connected to an inner wall of the cylindrical part 511 and an outer wall of a second cylindrical part 333; and an annular pressing member 53 which is pressed against the frictional-engagement element 52 so as to engage friction plates of the frictional-engagement element 52 with each other. The pressing member 53 forms a first annular clearance 531 in-between the inner wall of the cylindrical part 511. A hydraulic space 56 is formed on the side, opposite to the frictional-engagement element 52, of the pressing member 53. When hydraulic oil is supplied to the hydraulic space 56, the pressing member 53 is pressed against the frictional-engagement element 52, thereby engaging the friction plates of the frictional-engagement element 52 with each other, and consequently, connecting the output shaft 112 of the engine 11 and the rotor shaft 33 to each other.

Description

  The present invention relates to a power transmission device that transmits engine power to a transmission, and more particularly to a power transmission device that includes a motor generator and a clutch.

  2. Description of the Related Art Conventionally, there is known a power transmission device for a hybrid vehicle that includes a motor generator and a clutch and transmits engine power or motor generator power to a transmission by operating the clutch. In the power transmission device described in Patent Literature 1, the size of the power transmission device in the axial direction is reduced by disposing a clutch in a housing space formed in the rotor shaft radially inside the rotor of the motor generator. Yes. Here, the clutch has a plurality of friction plates and a pressing member that engages the friction plates by being pressed against the friction plates. The storage space is provided with a drum that forms a hydraulic space with the pressing member. The clutch is operated by pressing the pressing member against the friction plate by supplying hydraulic oil to the hydraulic space. The friction plate is lubricated and cooled by supplying hydraulic oil to the hydraulic space formed in the housing space.

  In the power transmission device of Patent Document 1, the drum is fixed to the rotor shaft that forms the housing space, and the state where the drum is in close contact with the pressing member is maintained regardless of whether the clutch is in operation or not. With such a configuration, there is a concern that hydraulic oil may stay around the friction plate in the housing space. If the hydraulic oil stays, the friction plate that has become high temperature due to frictional heat generated by friction between the friction plates during clutch operation cannot be sufficiently cooled by the hydraulic oil, and the friction plate may be in an abnormally high temperature state. As a result, the life of the friction plate may be shortened.

JP 2006-15997 A

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a power transmission device that is small in size and capable of maintaining initial performance over a long period of time.

  The invention according to claim 1 is a power transmission device for transmitting the driving force of the engine to the transmission, and includes a housing, a motor generator, and a clutch. The motor generator has a stator, a rotor, and a rotor shaft. The stator is formed in a cylindrical shape and is housed and fixed in the housing. A winding is wound around the stator. The rotor is formed in a cylindrical shape and is rotatably provided inside the stator. The rotor shaft is fitted to the inner wall of the rotor, is rotatably supported by the housing, and is connected to the input shaft of the transmission. The clutch is provided between the engine output shaft and the rotor shaft. The clutch can connect the output shaft of the engine and the rotor shaft. Thereby, the driving force output from the output shaft of the engine can be transmitted to the transmission via the rotor shaft.

  In the present invention, the rotor shaft includes a shaft portion formed at the end on the engine side, a first tube portion provided so that the outer wall is fitted to the inner wall of the rotor, and a second tube portion provided on the radially outer side of the shaft portion. And an annular portion that connects the inner wall of the first tube portion and the outer wall of the second tube portion. Between the 1st cylinder part and the 2nd cylinder part, the cylindrical accommodation space is formed in the engine side of the annular part. The clutch has a cylinder portion at least a part of which is located in the housing space, and is connected to the drum connected to the output shaft of the engine, the inner wall of the cylinder portion, and the outer wall of the second cylinder portion. The coupling element and an annular pressing member that is provided between the cylinder portion and the second cylinder portion and can be engaged with the friction engagement element by being pressed against the friction engagement element are provided. The pressing member forms an annular first gap between the inner wall of the cylindrical portion or one or a plurality of concave portions that are recessed radially inward at the outer edge portion. A hydraulic space is formed on the side of the pressing member opposite to the friction engagement element. Then, when the hydraulic oil is supplied to the hydraulic space, the pressing member is pressed against the frictional engagement element, whereby the frictional engagement element is engaged and the engine output shaft and the rotor shaft are connected.

  With the above configuration, the hydraulic oil supplied to the hydraulic space easily flows to the friction engagement element side via the first gap or the recess. Thus, the hydraulic oil can be circulated around the friction engagement element, and the friction engagement element can be effectively cooled and lubricated by the hydraulic oil. Therefore, abnormal heat generation of the friction engagement element when the clutch is operated can be suppressed. Therefore, the life of the friction engagement element can be extended, and the initial performance of the clutch can be maintained for a long time.

  In the present invention, as described above, at least a part of the drum cylinder in the axial direction, that is, at least a part of the clutch is housed in the housing space. That is, the clutch and the rotor are arranged so as to partially overlap in the axial direction of the rotor. Thereby, the physique of a power transmission device can be made small.

  Furthermore, in the present invention, the friction engagement element is accommodated inside the drum cylinder, that is, in the accommodation space. Therefore, even if the frictional engagement element is increased, the size of the power transmission device in the axial direction is not increased. Therefore, when the friction engagement element is constituted by a plurality of friction plates, for example, the amount of heat generated by the friction from each friction plate can be reduced by increasing the number of friction plates. Thereby, the abnormal heat generation of the clutch can be prevented without increasing the size of the power transmission device.

  In the invention described in claim 2, the pressing member forms an annular second gap between the pressing member and the outer wall of the second cylindrical portion. As a result, the hydraulic oil supplied to the hydraulic space easily flows to the friction engagement element side through the second gap as well as the first gap or the recess. Therefore, the friction engagement element can be cooled and lubricated more effectively by the hydraulic oil.

  In the invention according to claim 3, the clutch has a biasing member that biases the pressing member toward the hydraulic space. Thus, when the pressure in the hydraulic space is small, the engagement of the friction engagement element by the pressing member can be quickly released by the biasing member. In the present invention, the biasing member is provided on the radially outer side of the friction engagement element. Therefore, the pressing member can be more stably urged toward the hydraulic space by the urging member. In addition, since the effective diameter of the friction engagement element can be reduced, the amount of heat generated by the friction of the friction engagement element can be further reduced.

  The invention according to claim 4 is a power transmission device for transmitting the driving force of the engine to the transmission, and includes a housing, a motor generator, and a clutch. The motor generator has a stator, a rotor, and a rotor shaft. The stator is formed in a cylindrical shape and is housed and fixed in the housing. A winding is wound around the stator. The rotor is formed in a cylindrical shape and is rotatably provided inside the stator. The rotor shaft is fitted to the inner wall of the rotor, is rotatably supported by the housing, and is connected to the input shaft of the transmission. The clutch is provided between the engine output shaft and the rotor shaft. The clutch can connect the output shaft of the engine and the rotor shaft. Thereby, the driving force output from the output shaft of the engine can be transmitted to the transmission via the rotor shaft.

  In the present invention, the rotor shaft includes a shaft portion formed at the end on the engine side, a first tube portion provided so that the outer wall is fitted to the inner wall of the rotor, and a second tube portion provided on the radially outer side of the shaft portion. And an annular portion that connects the inner wall of the first tube portion and the outer wall of the second tube portion. Between the 1st cylinder part and the 2nd cylinder part, the cylindrical accommodation space is formed in the engine side of the annular part. The clutch has a cylindrical portion at least a part of which is located in the housing space, and is connected to the drum connected to the output shaft of the engine, the outer wall of the cylindrical portion, and the inner wall of the first cylindrical portion. The coupling element and an annular pressing member that is provided between the cylinder portion and the first cylinder portion and can be engaged with the friction engagement element by being pressed against the friction engagement element are provided. The pressing member forms an annular first gap between the inner wall of the first cylindrical portion or a single or a plurality of concave portions that are recessed radially inward at the outer edge portion. A hydraulic space is formed on the side of the pressing member opposite to the friction engagement element. Then, when the hydraulic oil is supplied to the hydraulic space, the pressing member is pressed against the frictional engagement element, whereby the frictional engagement element is engaged and the engine output shaft and the rotor shaft are connected.

  With the above configuration, the hydraulic oil supplied to the hydraulic space easily flows to the friction engagement element side via the first gap or the recess. Thus, the hydraulic oil can be circulated around the friction engagement element, and the friction engagement element can be effectively cooled and lubricated by the hydraulic oil. Therefore, abnormal heat generation of the friction engagement element when the clutch is operated can be suppressed. Therefore, the life of the friction engagement element can be extended, and the initial performance of the clutch can be maintained for a long time.

  In the present invention, as described above, at least a part of the drum cylinder in the axial direction, that is, at least a part of the clutch is housed in the housing space. That is, the clutch and the rotor are arranged so as to partially overlap in the axial direction of the rotor. Thereby, the physique of a power transmission device can be made small.

  Furthermore, in the present invention, the friction engagement element is accommodated in the outside of the drum cylinder, that is, in the accommodation space. Therefore, even if the frictional engagement element is increased, the size of the power transmission device in the axial direction is not increased. Therefore, when the friction engagement element is constituted by a plurality of friction plates, for example, the amount of heat generated by the friction from each friction plate can be reduced by increasing the number of friction plates. Thereby, the abnormal heat generation of the clutch can be prevented without increasing the size of the power transmission device.

  In the invention according to claim 5, the pressing member forms an annular second gap between the pressing member and the outer wall of the cylindrical portion. As a result, the hydraulic oil supplied to the hydraulic space easily flows to the friction engagement element side through the second gap as well as the first gap or the recess. Therefore, the friction engagement element can be cooled and lubricated more effectively by the hydraulic oil.

  In the invention according to claim 6, the clutch has a biasing member that biases the pressing member toward the hydraulic space. Thus, when the pressure in the hydraulic space is small, the engagement of the friction engagement element by the pressing member can be quickly released by the biasing member. In the present invention, the urging member is provided on the radially inner side of the friction engagement element.

  In the invention according to claim 7, the first gap is formed larger than the second gap. The hydraulic fluid supplied to the hydraulic space is frictionally engaged via the first gap by forming a larger gap (first gap) located radially outside of the first gap and the second gap. It becomes easier to flow to the element side. Therefore, the effect of cooling and lubricating the friction engagement element by the hydraulic oil can be further enhanced.

  In the inventions according to claims 8 and 9, the rotor shaft is formed with an oil passage communicating with the hydraulic space and through which the working oil flows. Therefore, hydraulic oil can be easily introduced into the oil passage from the transmission side. Thereby, it becomes easy to divert the hydraulic fluid supplied to the transmission for operating the transmission as the hydraulic fluid for the clutch. Therefore, it is not necessary to form a new hydraulic circuit for operating the clutch, and the cost can be reduced.

In the invention according to claim 8, the hydraulic space is formed on the engine side of the friction engagement element.
In the invention according to claim 9, the hydraulic space is formed on the transmission side of the friction engagement element. Therefore, the oil passage can be formed on the transmission side with respect to the friction engagement element. Thereby, the part inside a friction engagement element can be made hollow among rotor shafts. As a result, the inertia mass of the rotor shaft can be reduced.
In addition, in the above, “tubular” means, for example, “hollow cylindrical shape”, and includes a substantially cylindrical shape (substantially cylindrical shape). Further, “annular” means, for example, “annular” and includes a substantially annular shape (substantially annular shape).

The schematic diagram which shows the state which installed the power transmission device by 1st Embodiment of this invention in the vehicle. Sectional drawing which shows the power transmission device by 1st Embodiment of this invention. The figure for demonstrating arrangement | positioning of the damper of the power transmission device by 1st Embodiment of this invention, and looked at the drum of the flywheel, the damper, and the clutch from the transmission side of the axial direction. Sectional drawing which shows the power transmission device by 2nd Embodiment of this invention. Sectional drawing which shows the power transmission device by 3rd Embodiment of this invention. The figure which looked at the pressing member of the clutch of the power transmission device by other embodiment of this invention from the axial direction.

  Hereinafter, a power transmission device according to a plurality of embodiments of the present invention will be described with reference to the drawings. Note that, in a plurality of embodiments, substantially the same components are denoted by the same reference numerals, and description thereof is omitted.

(First embodiment)
A power transmission device according to a first embodiment of the present invention is shown in FIGS.
The power transmission device 1 is mounted on a hybrid vehicle using, for example, an engine and a motor as drive sources. In the present embodiment, the power transmission device 1 includes a motor (motor generator) as a drive source.

  As shown in FIG. 1, the power transmission device 1 is installed between a vehicle engine 11 and a transmission 12. The power transmission device 1 transmits the driving force output from the engine 11 as the first driving source to the transmission 12. The driving force transmitted to the transmission 12 is decelerated or increased by the transmission mechanism of the transmission 12 and transmitted to the axle 14 via the differential 13 as a differential device. Thereby, the wheel 15 rotates and the vehicle travels. In the present embodiment, the transmission 12 is a continuously variable transmission (CVT). The transmission mechanism of the transmission 12 is operated by hydraulic oil supplied from the pump 16.

  The power transmission device 1 includes a motor generator 30 as a second drive source. By transmitting the driving force of the motor generator 30 to the transmission 12, the vehicle can be driven by the driving force of the motor generator 30. Further, when the vehicle is driven by the driving force of the engine 11, the driving force of the motor generator 30 can be used as an auxiliary force for driving.

  Furthermore, in the present embodiment, the rotational power of the wheels 15 is transmitted to the motor generator 30 via the axle 14, the differential 13 and the transmission 12, so that the motor generator 30 can generate power. That is, the motor generator 30 generates power by so-called regenerative brake control. The electric power generated by the motor generator 30 is stored in the battery 17 and used for driving the motor generator 30 and for operating other devices and devices. The motor generator 30 is controlled by an electronic control unit (ECU) (not shown). The ECU controls devices and devices mounted on the vehicle based on information from sensors attached to the vehicle. The detailed configuration of the motor generator 30 will be described later.

As shown in FIG. 2, the power transmission device 1 includes a housing 20, a motor generator 30, a flywheel 40, a clutch 50, a damper 60, and the like.
The housing 20 is formed in a cylindrical shape from metal, for example. The housing 20 has one end connected to the engine housing 111 of the engine 11 and the other end connected to the transmission housing 121 of the transmission 12. The housing 20 includes a hollow cylindrical tube portion 21 and a disk-shaped support portion 22 extending radially inward from the inner wall of the tube portion 21. An insertion hole 221 is formed at the center of the support portion 22. The support portion 22 is formed with a housing cylinder portion 222 that extends in a hollow cylindrical shape from the edge of the insertion hole 221 toward the engine 11 side.

  The motor generator 30 is accommodated in the housing 20 so as to be positioned inside the cylindrical portion 21. The motor generator 30 has a stator 31, a rotor 32, and a rotor shaft 33. The stator 31 is formed in a hollow cylindrical shape by laminating silicon steel plates, for example. The stator 31 is accommodated and fixed in the housing 20 by fitting so that the outer wall faces the inner wall of the cylindrical portion 21. A plurality of windings 311 are wound around the stator 31. The winding 311 is wound around a plurality of salient poles that protrude inward in the radial direction of the stator 31.

  The rotor 32 is formed in a hollow cylindrical shape by laminating silicon steel plates, for example, like the stator 31. The rotor 32 is rotatably provided inside the stator 31 so that the outer wall faces the inner wall of the stator 31. A predetermined gap is formed between the outer wall of the rotor 32 and the inner wall of the stator 31.

  The rotor shaft 33 is formed in a substantially cylindrical shape from metal. The rotor shaft 33 includes a shaft portion 331, a first tube portion 332, a second tube portion 333, an annular portion 334, and a connection portion 335. The shaft portion 331 is formed at the end of the rotor shaft 33 on the engine 11 side. The first cylindrical portion 332 is provided so that the outer wall is fitted to the inner wall of the rotor 32. The second cylinder part 333 forms a substantially cylindrical space 34 between the outer wall of the shaft part 331. The annular part 334 connects the inner wall of the first cylinder part 332 and the outer wall of the second cylinder part 333. The connection part 335 connects the inner wall of the second cylinder part 333 and the outer wall of the shaft part 331. A substantially cylindrical accommodation space 35 is formed between the first cylinder portion 332 and the second cylinder portion 333 on the engine 11 side of the annular portion 334.

  The housing cylindrical portion 222 described above extends in a hollow cylindrical shape through the space 34 toward the engine 11 side, and a shaft portion 331 is inserted inside. Between the outer wall of the shaft portion 331 and the inner wall of the housing tube portion 222, a bearing 23 as a bearing portion is provided. The bearings 23 are formed in an annular shape, and two are provided so as to be aligned in the axial direction of the shaft portion 331.

  Thus, the shaft portion 331 of the rotor shaft 33 is rotatably supported by the housing tube portion 222 of the housing 20 via the bearing 23. Thereby, the rotor 32 is rotatably supported by the housing 20 via the rotor shaft 33 and the bearing 23. As described above, the rotor shaft 33 is fitted to the inner wall of the rotor 32 and is rotatably supported by the housing 20. The end of the rotor shaft 33 opposite to the shaft 331 is connected to the input shaft 122 of the transmission 12.

The flywheel 40 is formed in a substantially disc shape by metal, for example, and is connected to the output shaft 112 of the engine 11 by a bolt 18.
The clutch 50 is provided between the output shaft 112 of the engine 11 and the rotor shaft 33, more specifically, between the flywheel 40 and the rotor shaft 33. The clutch 50 includes a drum 51, a friction engagement element 52, a pressing member 53, and an urging member 54. The drum 51 has a substantially cylindrical tube portion 511 in which at least a part in the axial direction is located in the accommodation space 35.
The friction engagement element 52 includes a plurality of friction plates 521 and a plurality of friction plates 522. The plurality of friction plates 521 are formed in an annular shape, and are provided at predetermined intervals so that the outer edge portion is connected to the inner wall of the cylindrical portion 511. The plurality of friction plates 522 are formed in an annular shape having a smaller diameter than the friction plates 521, and are provided between the plurality of friction plates 521 so that the inner edge portion is connected to the outer wall of the second cylindrical portion 333 of the rotor shaft 33. Yes.

  The pressing member 53 is formed in a substantially annular shape, and is provided on the engine 11 side of the friction engagement element 52. Here, the pressing member 53 can contact the friction plate 521 located closest to the engine 11 among the plurality of friction plates 521. The pressing member 53 forms an annular first gap 531 between the pressing member 53 and the inner wall of the cylindrical portion 511 of the drum 51. Further, the pressing member 53 forms an annular second gap 532 between the pressing member 53 and the outer wall of the second cylindrical portion 333. Here, in the present embodiment, the first gap 531 is formed larger than the second gap.

  One end of the urging member 54 is accommodated in an accommodation groove 513 formed on the cylinder 11 511 of the drum 51 on the engine 11 side. The other end of the urging member 54 is in contact with the pressing member 53. The biasing member 54 is a coil spring in this embodiment, and has a force extending in the axial direction. Thereby, the urging member 54 urges the pressing member 53 toward the engine 11. The urging member 54 is provided on the radially outer side of the friction engagement element 52 as shown in FIG.

  A substantially disc-shaped plate member 55 is attached to the end surface of the rotor shaft 33 on the engine 11 side. The plate member 55 closes the engine 11 side opening of the cylindrical portion 511. Thereby, a substantially annular hydraulic space 56 is formed between the plate member 55 and the pressing member 53. That is, the hydraulic space 56 is formed on the side of the pressing member 53 opposite to the friction engagement element 52.

  In the present embodiment, a first oil passage 336 extending in the axial direction of the rotor shaft 33 and a radially outer side of the rotor shaft 33 extending from the first oil passage 336 to the hydraulic space 56 are communicated with the rotor shaft 33. A second oil passage 337 is formed. The hydraulic oil discharged from the pump 16 is supplied to the transmission mechanism of the transmission 12 and is controlled by a control valve (not shown) to be supplied to the hydraulic space 56 via the first oil passage 336 and the second oil passage 337. The When hydraulic oil is supplied to the hydraulic space 56, the pressure in the hydraulic space 56 increases. Then, the pressing member 53 moves to the transmission 12 side against the urging force of the urging member 54 and is pressed against the friction plate 521 located closest to the engine 11 side. Accordingly, the plurality of friction plates 521 connected to the cylindrical portion 511 of the drum 51 are pushed and moved together with the cylindrical portion 511 to the transmission 12 side, and are connected to the second cylindrical portion 333 of the rotor shaft 33. Engages with a plurality of friction plates 522. As a result, the flywheel 40 (output shaft 112) and the rotor shaft 33 are connected via the clutch 50. In the present embodiment, the hydraulic oil supplied to the hydraulic space 56 flows to the friction engagement element 52 side via the first gap 531 and the second gap 532.

  Thus, the clutch 50 has the friction engagement element 52, and the output shaft 112 and the rotor shaft 33 can be connected by engaging the friction engagement element 52. Thereby, the driving force output from the output shaft 112 of the engine 11 can be transmitted to the transmission 12 via the rotor shaft 33.

  The damper 60 is a coil spring in this embodiment, and can be elastically deformed in the axial direction. The damper 60 connects the flywheel 40 and the clutch 50. More specifically, as shown in FIG. 3, five dampers 60 are provided along the circumferential direction of the flywheel 40 between the flywheel 40 and the drum 51 of the clutch 50. The flywheel 40 and the drum 51 are relatively rotatable. When the flywheel 40 and the drum 51 rotate relative to each other, the damper 60 is elastically deformed.

  In the present embodiment, a clearance 101 having a predetermined size is formed between the outer wall of the second cylinder portion 333 of the rotor shaft 33 and the inner wall of the cylinder portion 511 of the drum 51. As a result, the hydraulic oil that has flowed from the hydraulic space 56 to the friction engagement element 52 side via the first gap 531 and the second gap 532 can flow out of the cylinder portion 511 via the clearance 101. . The hydraulic fluid that has flowed out through the clearance 101 reaches the bearing 23 between the cylinder portion 511 and the first cylinder portion 332 and between the rotor 32 and the stator 31, thereby lubricating the bearing 23. Is possible.

Next, an example of the operation of the power transmission device 1 according to the present embodiment will be described with reference to FIGS.
When the engine 11 is driven, the output shaft 112 rotates. Thereby, the flywheel 40 connected to the output shaft 112 and the clutch 50 connected by the flywheel 40 and the damper 60 rotate. At this time, since the output shaft 112 and the rotor shaft 33 are not connected, the driving force of the engine 11 is not transmitted to the rotor shaft 33.

  When hydraulic fluid is supplied from the pump 16 via the control valve, the first oil passage 336 and the second oil passage 337 to the hydraulic space 56, the pressure in the hydraulic space 56 increases, and the pressing member 53 moves to the friction engagement element 52. The plurality of friction plates 521 and the plurality of friction plates 522 of the friction engagement element 52 are engaged with each other. As a result, the flywheel 40 (output shaft 112) and the rotor shaft 33 are connected. As a result, the driving force of the engine 11 is transmitted to the input shaft 122 of the transmission 12 via the rotor shaft 33. The driving force of the engine 11 transmitted to the input shaft 122 is transmitted to the wheel 15 via the differential 13 and the axle 14. Thereby, the vehicle travels.

  At this time, the friction engagement element 52 is cooled and lubricated by the hydraulic fluid flowing from the hydraulic space 56 to the friction engagement element 52 via the first gap 531 and the second gap 532. The hydraulic fluid that has cooled and lubricated the frictional engagement element 52 flows out of the cylindrical portion 511 via the clearance 101 between the outer wall of the second cylindrical portion 333 and the inner wall of the cylindrical portion 511 of the drum 51. As described above, in the present embodiment, the hydraulic oil circulates around the friction engagement element 52 when the clutch 50 is operated.

  When the motor generator 30 is driven with the clutch 50 connecting the output shaft 112 and the rotor shaft 33, the driving force of the motor generator 30 passes through the rotor shaft 33 together with the driving force of the engine 11. It is transmitted to the input shaft 122. As described above, when the vehicle is driven by the driving force of the engine 11, the driving force of the motor generator 30 can be used as an auxiliary force for driving.

When the supply of hydraulic oil from the pump 16 to the hydraulic space 56 is stopped, the pressure in the hydraulic space 56 decreases. Therefore, the pressing member 53 moves to the engine 11 side by the urging force of the urging member 54. Accordingly, the engagement between the plurality of friction plates 521 and the plurality of friction plates 522 is released, and the connection between the output shaft 112 and the rotor shaft 33 is released. When the motor generator 30 is driven in this state, that is, when the output shaft 112 and the rotor shaft 33 are not connected, only the driving force of the motor generator 30 passes through the rotor shaft 33 and the input shaft of the transmission 12. 122. As described above, in the present embodiment, the vehicle can be driven only by the driving force of the motor generator 30.
Further, when the vehicle occupant performs a brake operation, regenerative brake control is performed by the ECU. Thereby, the motor generator 30 generates electric power, and the electric power generated by the electric power generation is accumulated in the battery 17.

  As described above, in the present embodiment, the rotor shaft 33 includes the shaft portion 331 formed at the end on the engine 11 side, the first tube portion 332 provided so that the outer wall is fitted to the inner wall of the rotor 32, and the shaft. It has the 2nd cylinder part 333 provided in the diameter direction outside of the part 331, and the annular part 334 which connects the inner wall of the 1st cylinder part 332, and the outer wall of the 2nd cylinder part 333. Between the first tube portion 332 and the second tube portion 333, a substantially cylindrical accommodation space 35 is formed on the engine 11 side of the annular portion 334. The clutch 50 has a cylindrical portion 511 having at least a portion in the axial direction located in the accommodation space 35, and is connected to the drum 51 connected to the output shaft 112 of the engine 11, the inner wall of the cylindrical portion 511, and the outer wall of the second cylindrical portion 333. The friction engagement element 52 provided to be connected, and the friction engagement element 52 provided between the cylinder portion 511 and the second cylinder portion 333 and being pressed against the friction engagement element 52 can be engaged. A possible annular pressing member 53 is provided. The pressing member 53 forms an annular first gap 531 between the inner wall of the cylindrical portion 511. A hydraulic space 56 is formed on the side of the pressing member 53 opposite to the friction engagement element 52. When the hydraulic oil is supplied to the hydraulic space 56, the pressing portion 53 is pressed against the friction engagement element 52, whereby the friction engagement element 52 is engaged, and the output shaft 112 and the rotor shaft 33 of the engine 11 are engaged. Are linked.

  With the above configuration, the hydraulic oil supplied to the hydraulic space 56 easily flows to the friction engagement element 52 side via the first gap 531. Accordingly, the hydraulic oil can be circulated around the friction engagement element 52, and the friction engagement element 52 can be effectively cooled and lubricated by the hydraulic oil. Therefore, abnormal heat generation of the friction engagement element 52 when the clutch 50 is operated can be suppressed. Therefore, the life of the friction engagement element 52 can be extended, and the initial performance of the clutch 50 can be maintained for a long time.

  In the present embodiment, as described above, at least a part of the cylinder 51 of the drum 51 in the axial direction, that is, at least a part of the clutch 50 (the cylinder 511, the friction engagement element 52, etc.) Is housed in. That is, the clutch 50 and the rotor 32 are arranged so as to partially overlap in the axial direction of the rotor 32. Thereby, the physique of the power transmission device 1 can be made small.

  In the present embodiment, the friction engagement element 52 is accommodated inside the cylinder portion 511 of the drum 51, that is, in the accommodation space 35. Therefore, even if the friction engagement element 52 is enlarged, the power transmission device 1 is not increased in size in the axial direction. Therefore, by increasing the number of the friction plates 521 and the friction plates 522 of the friction engagement element 52, the amount of heat generated by the friction from each friction plate 521 and each friction plate 522 can be reduced. Thereby, the abnormal heat generation of the clutch 50 can be prevented without increasing the size of the power transmission device 1.

  In this embodiment, the pressing member 53 forms an annular second gap 532 between the pressing member 53 and the outer wall of the second cylindrical portion 333. Accordingly, the hydraulic oil supplied to the hydraulic space 56 easily flows to the friction engagement element 52 side not only through the first gap 531 but also through the second gap 532. Therefore, the friction engagement element 52 can be cooled and lubricated more effectively by the hydraulic oil.

  In the present embodiment, the clutch 50 has a biasing member 54 that biases the pressing member 53 toward the hydraulic space 56. Thereby, when the pressure of the hydraulic space 56 is small, the engagement of the friction engagement element 52 by the pressing member 53 can be quickly released by the urging member 54. In the present embodiment, the biasing member 54 is provided on the radially outer side of the friction engagement element 52. Therefore, the pressing member 53 can be more stably urged toward the hydraulic space 56 by the urging member 54. In addition, since the effective diameter of the friction engagement element 52 can be reduced, the amount of heat generated by the friction of the friction engagement element 52 can be further reduced.

  In the present embodiment, the first gap 531 is formed larger than the second gap 532. Of the first gap 531 and the second gap 532, the hydraulic oil supplied to the hydraulic space 56 passes through the first gap 531 by forming a gap (first gap 531) that is located radially outward. Thus, it becomes easier to flow to the friction engagement element 52 side. Therefore, the effect of cooling and lubricating the friction engagement element 52 by the hydraulic oil can be further enhanced.

  Furthermore, in the present embodiment, the rotor shaft 33 is formed with a first oil passage 336 and a second oil passage 337 that communicate with the hydraulic space 56 and through which hydraulic oil flows. Therefore, the hydraulic oil can be easily introduced into the first oil passage 336 and the second oil passage 337 from the transmission 12 side. Thereby, it becomes easy to divert the hydraulic oil supplied to the transmission 12 to operate the transmission 12 as the hydraulic oil of the clutch 50. Therefore, it is not necessary to form a new hydraulic circuit for operating the clutch 50, and the cost can be reduced.

(Second Embodiment)
A power transmission device according to a second embodiment of the present invention is shown in FIG. The second embodiment differs from the first embodiment in the arrangement of the pressing member and the hydraulic space with respect to the friction engagement element.

  In the second embodiment, the pressing member 53 is provided on the transmission 12 side of the friction engagement element 52, unlike the first embodiment. Accordingly, the hydraulic space 56 is also formed on the transmission 12 side with respect to the friction engagement element 52. The urging member 54 is accommodated in an accommodation groove 613 formed on the transmission 12 side of the cylinder portion 611 of the drum 51, and is provided to urge the pressing member 53 toward the transmission 12 side. Further, the annular portion 334 of the rotor shaft 33 is formed to have a larger plate thickness than that of the first embodiment.

  In the second embodiment, the plate member 55 included in the first embodiment is not provided. In the present embodiment, a clearance 103 having a predetermined size is formed between the engine 11 side end portion of the cylinder portion 611 of the drum 51 and the engine 11 side end portion of the second cylinder portion 333. As a result, the hydraulic oil that has flowed from the hydraulic space 56 to the friction engagement element 52 side via the first gap 531 and the second gap 532 can flow out of the accommodation space 35 via the clearance 103. .

  In the present embodiment, a clearance 104 having a predetermined size is formed between the end portion of the cylinder portion 611 on the transmission 12 side and the annular portion 334. As a result, the hydraulic oil in the hydraulic space 56 can flow out of the hydraulic space 56 via the clearance 104. The hydraulic oil that has flowed out via the clearance 104 reaches the bearing 23 between the cylinder portion 611 and the first cylinder portion 332 and between the rotor 32 and the stator 31, thereby lubricating the bearing 23. Is possible.

  In the present embodiment, the second oil passage 337 is formed closer to the transmission 12 than the friction engagement element 52. Further, the rotor shaft 33 is formed so that the inner part of the friction engagement element 52 is hollow. That is, in this embodiment, the axial lengths of the shaft portion 331 and the connection portion 335 are shorter than those in the first embodiment.

  In the present embodiment, when hydraulic oil is supplied to the hydraulic space 56, the pressing member 53 comes into contact with and is pressed against the friction plate 521 located closest to the transmission 12 among the plurality of friction plates 521, thereby causing the drum 51. The cylinder portion 611 moves to the engine 11 side. Thereby, the friction engagement element 52 is engaged, and the output shaft 112 of the engine 11 and the rotor shaft 33 are connected.

Further, in the present embodiment, when the clutch 50 is operated, the friction engagement element 52 is caused by the hydraulic fluid flowing from the hydraulic space 56 to the friction engagement element 52 side via the first gap 531 and the second gap 532. Cooled and lubricated. The hydraulic oil that has cooled and lubricated the frictional engagement element 52 flows out of the accommodating space 35 via the clearance 103 between the cylindrical portion 611 and the second cylindrical portion 333. Thus, in this embodiment, like the first embodiment, the hydraulic oil circulates around the friction engagement element 52 when the clutch 50 is operated.
The points other than the above-described configuration of the second embodiment are the same as those of the first embodiment.

  As described above, in the present embodiment, the hydraulic oil supplied to the hydraulic space 56 is easily moved to the friction engagement element 52 side via the first gap 531 and the second gap 532 as in the first embodiment. Flowing into. Accordingly, the hydraulic oil can be circulated around the friction engagement element 52, and the friction engagement element 52 can be effectively cooled and lubricated by the hydraulic oil. Therefore, abnormal heat generation of the friction engagement element 52 when the clutch 50 is operated can be suppressed. Therefore, the life of the friction engagement element 52 can be extended, and the initial performance of the clutch 50 can be maintained for a long time.

  In the present embodiment, a hydraulic space 56 is formed on the transmission 12 side of the friction engagement element 52. Therefore, the second oil passage 337 can be formed closer to the transmission 12 than the friction engagement element 52. Thereby, the part inside the friction engagement element 52 of the rotor shaft 33 can be made hollow. As a result, the inertia mass of the rotor shaft 33 can be reduced.

(Third embodiment)
A power transmission device according to a third embodiment of the present invention is shown in FIG. The third embodiment differs from the second embodiment in the arrangement of frictional engagement elements and pressing members with respect to the drum cylinder.

  In the third embodiment, the friction engagement element 52 and the pressing member 63 are provided between the cylindrical portion 711 and the first cylindrical portion 332 of the drum 51, unlike the second embodiment. The plurality of friction plates 521 of the friction engagement element 52 are provided at a predetermined interval so that the inner edge portion is connected to the outer wall of the cylindrical portion 711. The plurality of friction plates 522 are formed in an annular shape having a larger diameter than the friction plates 521, and are provided between the plurality of friction plates 521 so that the outer edge portion is connected to the inner wall of the first cylindrical portion 332.

  The pressing member 63 is formed in a substantially annular shape and is provided on the transmission 12 side of the friction engagement element 52. Here, the pressing member 63 can contact the friction plate 521 located closest to the transmission 12 among the plurality of friction plates 521. The pressing member 63 forms an annular first gap 631 between the pressing member 63 and the inner wall of the first cylindrical portion 332. Further, the pressing member 63 forms an annular second gap 632 between the outer wall of the cylindrical portion 711. Here, in the present embodiment, the first gap 631 is formed larger than the second gap 632.

  One end of the urging member 54 is accommodated in an accommodation groove 713 formed on the transmission 12 side of the cylindrical portion 711. The other end of the urging member 54 is in contact with the pressing member 63. The urging member 54 urges the pressing member 63 toward the transmission 12. The urging member 54 is provided on the radially inner side of the friction engagement element 52 as shown in FIG.

  In the present embodiment, a through hole 714 that connects the outer wall and the inner wall is formed at the end of the cylindrical portion 711 on the engine 11 side. A clearance 105 having a predetermined size is formed between the end of the first cylinder portion 332 of the rotor shaft 33 on the engine 11 side and the drum 51. As a result, the hydraulic fluid that has flowed from the hydraulic space 56 to the friction engagement element 52 side via the first gap 631 and the second gap 632 goes to the outside of the accommodation space 53 via the through hole 714 and the clearance 105. Can flow out. The hydraulic oil that has flowed out via the clearance 105 reaches the bearing 23 via the space between the rotor 32 and the stator 31, so that the bearing 23 can be lubricated.

  In the present embodiment, when hydraulic oil is supplied to the hydraulic space 56, the pressing member 63 comes into contact with and is pressed against the friction plate 521 located closest to the transmission 12 among the plurality of friction plates 521, thereby causing the drum 51. The cylinder portion 711 moves to the engine 11 side. Thereby, the friction engagement element 52 is engaged, and the output shaft 112 of the engine 11 and the rotor shaft 33 are connected.

Further, in the present embodiment, when the clutch 50 is operated, the friction engagement element 52 is caused by the hydraulic oil flowing from the hydraulic space 56 to the friction engagement element 52 side via the first gap 631 and the second gap 632. Cooled and lubricated. The hydraulic oil that has cooled and lubricated the friction engagement element 52 flows out of the accommodation space 35 through the through hole 714 and the clearance 105. Thus, in this embodiment, like the second embodiment, the hydraulic oil circulates around the friction engagement element 52 when the clutch 50 is operated.
Points other than the above-described configuration of the third embodiment are the same as those of the second embodiment.

  As described above, in the present embodiment, the hydraulic oil supplied to the hydraulic space 56 is easily moved to the friction engagement element 52 side via the first gap 631 and the second gap 632 as in the second embodiment. Flowing into. Accordingly, the hydraulic oil can be circulated around the friction engagement element 52, and the friction engagement element 52 can be effectively cooled and lubricated by the hydraulic oil. Therefore, abnormal heat generation of the friction engagement element 52 when the clutch 50 is operated can be suppressed. Therefore, the life of the friction engagement element 52 can be extended, and the initial performance of the clutch 50 can be maintained for a long time.

(Other embodiments)
In the above-described embodiment, an example in which an annular first gap is formed between the pressing member and the inner wall of the drum cylinder portion or between the pressing member and the inner wall of the first cylinder portion of the rotor shaft has been shown. . On the other hand, in another embodiment of the present invention, a concave portion 533 that is recessed radially inward is formed in the outer edge portion of the pressing member 53, for example, as shown in FIG. It is good also as a structure. A plurality of the recesses 533 may be formed, or a single recess may be formed. By forming such a recess 533, the hydraulic oil in the hydraulic space can flow to the friction engagement element side via the recess 533.

  Moreover, in the above-mentioned embodiment, the example which forms a cyclic | annular 2nd clearance gap between the pressing member and the outer wall of the 2nd cylinder part of a rotor shaft, or between the pressing member and the outer wall of the cylinder part of a drum was shown. On the other hand, in other embodiment of this invention, it is good also as forming only a 1st clearance gap or a recessed part in the outer edge part of a pressing member, without forming a 2nd clearance gap.

  Moreover, in the above-mentioned embodiment, the example in which the 1st clearance gap was formed larger than the 2nd clearance gap was shown. On the other hand, in another embodiment of the present invention, the first gap may be smaller than the second gap.

In the above-described embodiment, the example in which the friction engagement element is configured by a plurality of friction plates has been described. On the other hand, in another embodiment of the present invention, the friction engagement element may be constituted by a single friction plate.
In another embodiment of the present invention, the clutch may operate by being supplied with hydraulic oil from a pump other than a pump that supplies hydraulic oil for the transmission.
The power transmission device according to the present invention can also be applied to a vehicle equipped with a transmission other than CVT (for example, AT).

  Thus, the present invention is not limited to the above-described embodiments, and can be applied to various forms without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 1 ... Power transmission device 11 ... Engine 112 ... Output shaft 12 ... Transmission 122 ... Input shaft 20 ... Housing 30 ... Motor generator 31 ... ··· Stator 311 ··· Winding 32 ··· Rotor 33 ··· Rotor shaft 331 ··· Shaft portion 332 ··· First tube portion 333 · · · Second tube portion 334 · · · Ring portion 35 ··· Storage space 50 ··· Clutch 51 ··· Drums 511, 611, 711 ··· Tube portion 52 ··· Friction engagement elements 53 and 63 ··· Pushing member 531 631... First gap 533... Recess 56... Hydraulic space

Claims (9)

A power transmission device for transmitting engine driving force to a transmission,
A housing;
A cylindrical stator that is housed and fixed in the housing and wound with a winding, a cylindrical rotor that is rotatably provided inside the stator, and an inner wall of the rotor that fits and can rotate on the housing A motor generator having a rotor shaft supported by and connected to the input shaft of the transmission;
A clutch provided between the output shaft of the engine and the rotor shaft, and capable of connecting the output shaft and the rotor shaft;
The rotor shaft is
A shaft formed at the end of the engine,
A first cylindrical portion provided so that an outer wall is fitted to the inner wall of the rotor;
A second cylindrical portion provided on the radially outer side of the shaft portion, and
An annular portion connecting the inner wall of the first tube portion and the outer wall of the second tube portion;
Between the first cylinder part and the second cylinder part, a cylindrical accommodation space is formed on the engine side of the annular part,
The clutch is
A drum having at least a part in the axial direction and having a cylindrical portion located in the accommodation space, connected to the output shaft;
A frictional engagement element provided to connect to the inner wall of the cylindrical portion and the outer wall of the second cylindrical portion; and
An annular pressing member that is provided between the cylindrical portion and the second cylindrical portion and is capable of engaging the friction engagement element by being pressed against the friction engagement element;
The pressing member is formed with an annular first gap between the inner wall of the cylindrical portion, or a single or a plurality of concave portions recessed radially inward at an outer edge portion,
On the opposite side of the pressing member from the friction engagement element, a hydraulic space is formed,
When the hydraulic oil is supplied to the hydraulic space, the pressing member is pressed against the friction engagement element, whereby the friction engagement element is engaged, and the output shaft and the rotor shaft are connected. Power transmission device.   2. The power transmission device according to claim 1, wherein the pressing member forms an annular second gap between the pressing member and an outer wall of the second cylindrical portion. The clutch has a biasing member that biases the pressing member toward the hydraulic space,
The power transmission device according to claim 1, wherein the urging member is provided on a radially outer side of the friction engagement element. A power transmission device for transmitting engine driving force to a transmission,
A housing;
A cylindrical stator that is housed and fixed in the housing and wound with a winding, a cylindrical rotor that is rotatably provided inside the stator, and an inner wall of the rotor that fits and can rotate on the housing A motor generator having a rotor shaft supported by and connected to the input shaft of the transmission;
A clutch provided between the output shaft of the engine and the rotor shaft, and capable of connecting the output shaft and the rotor shaft;
The rotor shaft is
A shaft formed at the end of the engine,
A first cylindrical portion provided so that an outer wall is fitted to the inner wall of the rotor;
A second cylindrical portion provided on the radially outer side of the shaft portion, and
An annular portion connecting the inner wall of the first tube portion and the outer wall of the second tube portion;
Between the first cylinder part and the second cylinder part, a cylindrical accommodation space is formed on the engine side of the annular part,
The clutch is
A drum having at least a part in the axial direction and having a cylindrical portion located in the accommodation space, connected to the output shaft;
A friction engagement element provided to connect to an outer wall of the tube portion and an inner wall of the first tube portion; and
An annular pressing member that is provided between the cylindrical portion and the first cylindrical portion and is capable of engaging the friction engagement element by being pressed against the friction engagement element;
The pressing member forms an annular first gap between the inner wall of the first cylindrical portion, or a single or a plurality of concave portions that are recessed radially inward at an outer edge portion,
On the opposite side of the pressing member from the friction engagement element, a hydraulic space is formed,
When the hydraulic oil is supplied to the hydraulic space, the pressing member is pressed against the friction engagement element, whereby the friction engagement element is engaged, and the output shaft and the rotor shaft are connected. Power transmission device.   The power transmission device according to claim 4, wherein the pressing member forms an annular second gap between the pressing member and the outer wall of the cylindrical portion. The clutch has a biasing member that biases the pressing member toward the hydraulic space,
The power transmission device according to claim 4, wherein the urging member is provided on a radially inner side of the friction engagement element.   The power transmission device according to any one of claims 2, 3, 5, and 6, wherein the first gap is formed to be larger than the second gap. The rotor shaft is formed with an oil passage that communicates with the hydraulic space and through which the hydraulic oil flows.
The power transmission device according to claim 1, wherein the hydraulic space is formed on the engine side of the friction engagement element. The rotor shaft is formed with an oil passage that communicates with the hydraulic space and through which the hydraulic oil flows.
The power transmission apparatus according to claim 1, wherein the hydraulic space is formed on the transmission side of the friction engagement element.

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