Hybrid vehicle power transmission device

Abstract

To provide a hybrid vehicle power transmission device capable of being downsized while increasing a contact area between first and second friction plates.SOLUTION: A power transmission device 4 comprises a pressure plate 32 which connects a clutch input member 26 to an input side friction plate 30 and an output side friction plate 31 through the input side friction plate 30 and the output side friction plate 31. The pressure plate 32 has a plurality of through holes 32a penetrating the pressure plate 32 in a radial direction. The output side friction plate 31 has a plurality of inner side protrusion sections 31b which is inwardly protruded in the radial direction from an inner edge section of the output side friction plate 31 and engaged with the through holes 32a. The pressure plate 32 and the output side friction plate 31 integrally rotate.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a power transmission device for a hybrid vehicle. [Background technology]

[0002] BACKGROUND ART A power transmission device equipped with a multi-plate friction clutch, as described in Patent Document 1, is known as a device equipped with a clutch that can connect and disconnect power between an internal combustion engine and a transmission.

[0003] This power transmission device has a clutch outer to which engine power is transmitted via a primary driven gear and a damper rubber, a plurality of friction plates whose outer ends are connected to the outer cylindrical portion of the clutch outer, a clutch center connected to the main shaft of the transmission, and a plurality of clutch plates whose inner ends are connected to the center cylindrical portion of the clutch center and which are arranged alternately with the friction plates.

[0004] In addition, the multi-plate friction clutch has a pressure plate that is biased by a clutch spring and presses the friction plates and clutch plates against the clutch center so that they come into contact with each other, thereby connecting the clutch outer and the clutch center and enabling power to be transmitted from the engine to the transmission. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-175472 Summary of the Invention [Problem to be solved by the invention]

[0006] In the multi-plate friction clutch described in Patent Document 1, it is conceivable to reduce the number of friction plates and clutch plates in order to shorten the dimension of the power transmission device in the main shaft direction.

[0007] However, when the number of friction plates and clutch plates is reduced, it is necessary to increase the contact area between the friction plates and the clutch plates to prevent a decrease in clutch performance.

[0008] In the multi-plate friction clutch described in Patent Document 1, the inner ends of the clutch plates are connected to the center cylindrical portion of the clutch center, and the center cylindrical portion gets in the way, preventing the friction plates and clutch plates from expanding radially inward, making it difficult to increase the contact area between the friction plates and clutch plates.

[0009] The present invention has been made in light of the above-mentioned circumstances, and aims to provide a power transmission device for a hybrid vehicle that can be made smaller while increasing the contact area between the first friction plate and the second friction plate. [Means for solving the problem]

[0010] The present invention provides a power transmission device for a hybrid vehicle, which is disposed between an internal combustion engine and a transmission, and which transmits power from a rotating electric machine to the transmission, and which has a clutch capable of connecting and disconnecting power between the internal combustion engine and the transmission, wherein the clutch comprises a clutch input member to which power is transmitted from the internal combustion engine, a clutch output member which is connected to a rotary shaft of the transmission and which interlocks with the rotating electric machine, a friction member which connects and disconnects the clutch input member and the clutch output member, and a biasing member which biases the friction member against the clutch output member, thereby connecting and disconnecting the friction member. and a pressing member that connects the clutch input member and the clutch output member via a member, the friction member having a first friction plate that rotates integrally with the clutch input member and a second friction plate that is arranged alternately with the first friction plate, the pressing member having a plurality of through holes that penetrate the pressing member in the radial direction, the second friction plate having a plurality of engaging portions that protrude radially inward from an inner end of the second friction plate and engage with the through holes, and the pressing member and the second friction plate rotate integrally. [Effects of the Invention]

[0011] As described above, according to the present invention, it is possible to increase the contact area between the first friction plate and the second friction plate, while also reducing the size of the power transmission device. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view of a power transmission device disposed between an internal combustion engine and a transmission according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic diagram of a hybrid vehicle equipped with a power transmission device according to one embodiment of the present invention. [Figure 3] FIG. 3 is a cross-sectional view of a power transmission device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a view of the damper and wet clutch of the power transmission device according to one embodiment of the present invention, as viewed from the transmission side. [Figure 5] 5 is a cross-sectional view taken along the arrows VV in FIG. [Figure 6] 6 is a cross-sectional view taken along the line VI-VI in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] A power transmission device for a hybrid vehicle according to one embodiment of the present invention is arranged between an internal combustion engine and a transmission, transmits power from a rotating electric machine to the transmission, and has a clutch that can connect and disconnect power between the internal combustion engine and the transmission, the clutch including a clutch input member to which power is transmitted from the internal combustion engine, a clutch output member that is connected to a rotating shaft of the transmission and interlocks with the rotating electric machine, a friction member that connects and disconnects the clutch input member and the clutch output member, and a biasing member that biases the friction member to the clutch output member. The clutch clutch has a pressing member that connects the clutch input member and the clutch output member via the friction member by pressing it against a force member, and the friction member has a first friction plate that rotates integrally with the clutch input member and a second friction plate that is arranged alternately with the first friction plate, the pressing member has a plurality of through holes that penetrate the pressing member in the radial direction, and the second friction plate has a plurality of engaging portions that protrude radially inward from an inner end of the second friction plate and engage with the through holes, and the pressing member and the second friction plate rotate integrally.

[0014] As a result, the power transmission device for a hybrid vehicle according to one embodiment of the present invention can increase the contact area between the first friction plate and the second friction plate, while also achieving a reduction in the size of the power transmission device. [Example]

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A power transmission device for a hybrid vehicle according to an embodiment of the present invention will now be described with reference to the drawings.

[0016] 1 to 6 are diagrams showing a power transmission device for a hybrid vehicle according to one embodiment of the present invention.

[0017] First, the configuration will be described. In Figures 1 to 6, the up, down, front, back, left and right directions are based on the power transmission device when installed in a hybrid vehicle, and the front and back direction of the hybrid vehicle is the front-to-rear direction, the left and right direction of the hybrid vehicle (vehicle width direction) is the left and right direction, and the up and down direction of the hybrid vehicle (height direction of the hybrid vehicle) is the up and down direction.

[0018] As shown in Fig. 1, a hybrid vehicle has an internal combustion engine 1, a motor generator 2 (see Fig. 2) as a rotating electric machine, and a transmission 3. A power transmission device 4 is disposed between the internal combustion engine 1 and the transmission 3.

[0019] The internal combustion engine 1 includes an engine body 1A, and a crankshaft 1B extending in the vehicle width direction (left-right direction) is rotatably housed in the engine body 1A.

[0020] The internal combustion engine 1 burns fuel to convert thermal energy into mechanical energy, thereby rotating the crankshaft 1B about its central axis of rotation, and transmitting power to the transmission 3 via the power transmission device 4.

[0021] As shown in Fig. 2, the motor generator 2 is disposed on the internal combustion engine 1 side with respect to the power transmission device 4. The motor generator 2 transmits power to the transmission 3 via the power transmission device 4, and also has a regenerative function of generating electricity using the power transmitted from the transmission 3 via the power transmission device 4.

[0022] Specifically, the motor generator 2 functions as an electric motor that generates power using electricity supplied from a battery (not shown) via an inverter (not shown), and as a generator that generates regenerative power using the rotational force (reverse driving force) input from the drive wheels 6L and 6R.

[0023] Under the control of an ECU (not shown), the inverter converts DC power supplied from the battery into three-phase AC power and supplies it to the motor generator 2, and also converts the three-phase AC power generated by the motor generator 2 into DC power to charge the battery. The battery is formed of a secondary battery such as a lithium-ion battery.

[0024] The inverter and battery of this embodiment may be provided integrally with the motor generator 2, or may be unitized and attached to the engine body 1A of the internal combustion engine 1. The motor generator 2 of this embodiment constitutes a rotating electric machine.

[0025] The transmission 3 includes a gear-changing clutch 3A and a gear change mechanism 3B. The gear-changing clutch 3A mechanically connects and disconnects the power transmitted from at least one of the internal combustion engine 1 and the motor generator 2.

[0026] Although not shown in detail, the transmission mechanism 3B is equipped with a plurality of transmission gears and synchronizers, etc., and changes the speed of the power (rotation) transmitted from at least one of the internal combustion engine 1 and the motor generator 2 according to the gear stage, and transmits it to the left and right drive wheels 6L, 6R via the left and right drive shafts 5L, 5R from a differential device not shown.

[0027] Furthermore, the gear change clutch 3A is mechanically disengaged when the gear is changed and is mechanically engaged when the gear is established. In other words, when the gear change clutch 3A is engaged, it connects the power transmission device 4 and the transmission 3 to transmit power, and when it is disengaged, it disconnects the power transmission device 4 and the transmission 3 to interrupt the transmission of power.

[0028] As shown in FIG. 1, the power transmission device 4 is disposed between the internal combustion engine 1 and the transmission 3, and transmits power from the motor generator 2 to the transmission 3, and has a wet clutch 25 (described later) that can connect and disconnect power between the internal combustion engine 1 and the transmission 3.

[0029] 1 and 3, the power transmission device 4 has a thin, flat shape in the axial direction (the direction in which C1, which will be described later, extends) and includes a case 10 that forms an outer shell. The case 10 is divided in the left-right direction, and has a right case portion 10A located on the internal combustion engine 1 side and a left case portion 10B located on the transmission 3 side.

[0030] Bosses 10a, 10b are provided on the outer end of the right case portion 10A and the outer end of the left case portion 10B, and the bosses 10a, 10b are fastened together with bolts 9A. This integrates the right case portion 10A and the left case portion 10B. The case 10 is disposed between the internal combustion engine 1 and the transmission 3, and is connected to the internal combustion engine 1 and the transmission 3.

[0031] The right case portion 10A and the left case portion 10B are provided with annular bearing support portions 10c and 10d, respectively, and the drive shaft 2A of the motor generator 2 is rotatably supported by the bearing support portions 10c and 10d via bearings 11A and 11B.

[0032] An opening 10e is formed in the right case portion 10A, and the right end of the drive shaft 2A is disposed so as to protrude from the opening 10e to the outside of the case 10. An oil seal 12A is provided between the opening 10e and the drive shaft 2A, and the gap between the opening 10e and the drive shaft 2A is closed by the oil seal 12A.

[0033] A drive gear 2B is housed inside the case 10 and is located between the bearing supports 10c and 10d. The drive gear 2B is spline-fitted to the outer periphery of the drive shaft 2A and rotates integrally with the drive shaft 2A.

[0034] The case 10 accommodates a damper 21. The damper 21 has a damper input member 22, a damper output member 23, and a coil spring 24.

[0035] The damper 21 is disposed at the same position in the axial direction (the direction in which C1, which will be described later, extends) as the bearing support portion 10c. In other words, the bearing support portion 10c is disposed radially outside the damper 21. Interference between the damper 21 and the bearing support portion 10c in the radial direction is avoided, and the axial length (thickness) of the power transmission device 4 can be shortened.

[0036] The damper 21 is a disk-shaped component that is thin in the axial direction, and is arranged along the right case portion 10A on the internal combustion engine 1 side inside the case 10. A shaft mounting portion 22A is provided at the inner end of the damper input member 22, and the shaft mounting portion 22A is fastened to the crankshaft 1B by a bolt 9B.

[0037] Specifically, the crankshaft 1B has a plurality of threaded holes 1a formed around the rotational axis thereof, the threaded holes 1a extending in the direction of the rotational axis (left-right direction) of the crankshaft 1B.

[0038] The shaft mounting portion 22A has a plurality of through holes 22a through which the bolts 9B pass, formed to match the positions of the screw holes 1a, and the through holes 22a face the screw holes 1a in the direction of the central axis of rotation of the damper 21.

[0039] The shaft mounting portion 22A is mounted to the crankshaft 1B by inserting a bolt 9B into the through hole 22a and threading the bolt 9B into the threaded hole 1a, thereby causing the damper input member 22 to rotate integrally with the crankshaft 1B.

[0040] As shown in FIG. 3, the damper input member 22 has an inner circular plate portion 22B that extends radially outward from the shaft mounting portion 22A in a circular plate shape, an outer circular plate portion 22C that is connected to the inner circular plate portion 22B via a pin 7 and extends radially outward from the inner circular plate portion 22B in a circular plate shape, and a spring holding portion 22D that is provided at the outer end of the outer circular plate portion 22C and holds a coil spring 24 that is arranged together with the damper output member 23 along the circumferential direction.

[0041] The shaft attachment portion 22A, the inner disc portion 22B, the outer disc portion 22C and the spring holding portion 22D rotate integrally with the crankshaft 1B.

[0042] The coil spring 24 is arranged between the outer end of the damper input member 22 and the outer end of the damper output member 23 with its coil axis aligned in the circumferential direction so as to be expandable and contractible in the direction of the coil axis.

[0043] The driving force is transmitted between the damper input member 22 and the damper output member 23 via a coil spring 24. The elastic deformation of the coil spring 24 allows relative rotational displacement between the damper input member 22 and the damper output member 23, absorbing minute fluctuations in the driving force.

[0044] Specifically, when the rotation of the crankshaft 1B causes the damper input member 22 to rotate, the rotation of the damper input member 22 is transmitted to the damper output member 23 via the coil spring 24. As a result, the damper output member 23 and the damper input member 22 rotate integrally.

[0045] Here, when rotational fluctuations (torque fluctuations) occur in the rotation of the internal combustion engine 1, the coil spring 24 elastically deforms in the circumferential direction to absorb the fluctuations, and the damper input member 22 and the damper output member 23 rotate relative to each other, so that the rotational fluctuations of the internal combustion engine 1 are absorbed without being transmitted from the damper input member 22 to the damper output member 23.

[0046] In other words, the coil spring 24 elastically deforms in the direction of the coil axis between the damper input member 22 and the damper output member 23 to allow relative displacement between the damper input member 22 and the damper output member 23 in the rotational direction, and transmits torque while absorbing vibrations in the rotational speed.

[0047] 1 and 3, a wet clutch 25 is housed in the case 10. The wet clutch 25 has a clutch input member 26, a driven gear 27 that constitutes a clutch output member, and an urging member 28 (see FIG. 5).

[0048] The wet clutch 25 is disposed on the transmission 3 side with respect to the damper 21. That is, the damper 21 is disposed between the wet clutch 25 and the internal combustion engine 1 in the direction of the central axis of rotation of the wet clutch 25. The wet clutch 25 of this embodiment constitutes a clutch.

[0049] The clutch input member 26 is formed integrally with the damper output member 23, and extends cylindrically from the outer end of the damper output member 23 toward the transmission 3.

[0050] The driven gear 27 is disposed on the transmission 3 side with respect to the damper 21, and has teeth 27a formed on its outer periphery to mesh with the drive gear 2B.

[0051] Here, the rotational axis of the crankshaft 1B, the rotational axis of the flywheel 3C, the rotational axis of the damper 21, and the rotational axis of the wet clutch 25, including the rotational axis of the flywheel 3C described later, are all the same rotational axis C1, and the crankshaft 1B, the flywheel 3C, the damper 21, and the wet clutch 25 are arranged so that the rotational axis C1 is horizontal. Hereinafter, the direction in which the rotational axis C1 of each of these members extends will be referred to as the rotational axis direction.

[0052] The driven gear 27 is connected to the motor generator 2 via the drive gear 2B and is interlocked with the motor generator 2. The driven gear 27 has a larger diameter than the drive gear 2B, and the driving force of the motor generator 2 is reduced by the driven gear 27. In other words, the driven gear 27 is a gear for reduction.

[0053] The drive gear 2B of this embodiment is disposed so that its rotational axis C2 is horizontal, and the rotational axis C1 of the driven gear 27 and the rotational axis C2 of the drive gear 2B are parallel to each other.

[0054] An input side friction plate 30, an output side friction plate 31, and a pressure plate 32 are arranged in the inner space (inner diameter side space) of the cylindrical clutch input member .

[0055] A plurality of input side friction plates 30 are spline-fitted to the inner periphery of the clutch input member 26, and the input side friction plates 30 are rotatable integrally with the clutch input member 26 and are movable in the direction of the rotational center axis relative to the clutch input member 26.

[0056] As shown in FIG. 6, each input side friction plate 30 has an annular contact portion 30a and outer protruding portions 30b that protrude radially outward from the outer end of the contact portion 30a and are spaced apart at equal intervals in the circumferential direction.

[0057] As shown in FIG. 4, the clutch input member 26 is formed with a recess 26a that is recessed radially outward and faces the outer protrusion 30b in the radial direction, and the outer protrusion 30b is disposed within the recess 26a and engages with the recess 26a.

[0058] In other words, the outer protrusion 30b of the input side friction plate 30 constitutes an outer peripheral spline that is formed continuously in the circumferential direction, and the recess 26a of the clutch input member 26 constitutes an inner peripheral spline that is formed continuously in the circumferential direction and is spline-fitted with the outer peripheral spline.

[0059] As a result, the input side friction plate 30 is attached so as to be movable in the direction of the rotational axis relative to the clutch input member 26 but not movable in the rotational direction, and rotates integrally with the clutch input member 26.

[0060] As shown in FIG. 3, the driven gear 27 has a tooth portion 27a formed on its outer end (outer peripheral edge), an annular outer disk portion 27A whose outer edge is connected to the inner diameter portion of the tooth portion 27a closer to the damper 21, an outer cylindrical portion 27B extending cylindrically from the inner end of the outer disk portion 27A towards the transmission 3, an inner disk portion 27C extending radially inward from the right end (end on the damper 21 side) of the outer cylindrical portion 27B, and a shaft portion 27D protruding cylindrically from the inner end of the inner disk portion 27C towards the internal combustion engine 1.

[0061] The shaft portion 27D is disposed at the same axial position as the damper 21 and fits into the inner diameter side of the damper 21, and fits between the shaft attachment portion 22A and the bolt 9B. The inner disk portion 27C is formed with an access hole that allows the bolt 9B to be tightened.

[0062] As shown in Fig. 1, a flywheel 3C and a gear-changing clutch 3A are provided in the transmission 3. As shown in Fig. 3, a shaft portion 3a of the flywheel 3C, which serves as the rotating shaft, is fitted into a fitting hole 27c formed on the left side (the transmission 3 side) of a shaft portion 27D of the driven gear 27, and in this state the flywheel 3C is fixed to the driven gear 27 by a plurality of bolts 9C that are tightened from the transmission 3 side.

[0063] The fastening points of the multiple bolts 9C in the driven gear 27 are arranged between the work holes for the multiple bolts 9B. The mounting pitch diameters of the bolts 9C and 9B are approximately the same and are set on the inner diameter side of the outer cylindrical portion 27B.

[0064] As a result, the driven gear 27 rotates integrally with the flywheel 3C. The shaft portion 3a in this embodiment forms a rotation shaft.

[0065] As shown in FIG. 1, an input shaft 3D of a transmission 3 is rotatably supported by a flywheel 3C via a bearing 11D, and the input shaft 3D is supported by the bearing 11D so as to be rotatable relative to the flywheel 3C.

[0066] The input shaft 3D and the flywheel 3C are connected to each other so that power can be transmitted via a gear-shift clutch 3A. When the gear-shift clutch 3A is engaged, power is transmitted between the input shaft 3D and the flywheel 3C, and when the gear-shift clutch 3A is disengaged, power is cut off between the input shaft 3D and the flywheel 3C.

[0067] 3, a hole serving as bearing support portion 22b is provided at the axis of shaft attachment portion 22A of damper input member 22, and bearing 11C is disposed in bearing support portion 22b. Shaft portion 27D of driven gear 27 is rotatably supported by bearing 11C on damper input member 22. In other words, damper input member 22 and driven gear 27 rotate relative to each other via bearing 11C.

[0068] As shown in FIGS. 3 and 5, the biasing member 28 has an annular pressure plate 32, a disc spring 33, and an annular spring fixing flange 34.

[0069] The pressing plate 32 has a pressing portion 32A, a plate holding portion 32B that extends cylindrically from the radially inner end of the pressing portion 32A toward the transmission 3, and a disk portion 32C that bends conically radially inward from the left end (transmission 3 side end) of the plate holding portion 32B and bulges slightly toward the internal combustion engine 1, and then extends radially inward.

[0070] 6, the output friction plates 31 are attached to the cylindrical plate holding portion 32B so as to surround it. Each output friction plate 31 has an annular contact portion 31a and inner protruding portions 31b that protrude radially inward from the inner end of the contact portion 31a and are spaced apart at equal intervals in the circumferential direction.

[0071] 4 and 6, a plurality of through holes 32a are formed in the cylindrical plate holding portion 32B. The through holes 32a penetrate the pressing plate 32 in the radial direction so as to communicate the inside and outside of the plate holding portion 32B, and are arranged at equal intervals in the circumferential direction of the pressing plate 32.

[0072] The inner protrusion 31b of the output side friction plate 31 is inserted into the through hole 32a and positioned therein, and the inner protrusion 31b is engaged with the through hole 32a, so that the output side friction plate 31 is attached so as to be movable in the direction of the rotational axis relative to the pressing plate 32 but not movable in the rotational direction.

[0073] As a result, the output side friction plate 31 rotates integrally with the pressure plate 32. The pressure plate 32 of this embodiment constitutes a pressure member, and the inner protrusion 31b constitutes an engagement portion.

[0074] The input side friction plate 30 constitutes a first friction plate, the output side friction plate 31 constitutes a second friction plate, and the input side friction plate 30 and the output side friction plate 31 constitute a friction member.

[0075] 3, a release pin 41 is attached to the disc portion 32C so as to protrude toward the transmission 3. More specifically, through holes 32b are formed in the disc portion 32C. The through holes 32b are formed at equal intervals in the circumferential direction of the pressure plate 32, and the right ends of the release pins 41 are fitted into and fixed to the through holes 32b. In other words, a release pin 41 is provided for each through hole 32b and is arranged at equal intervals in the circumferential direction of the pressure plate 32.

[0076] The outer disk portion 27A of the driven gear 27 has through holes 27b formed at positions corresponding to the release pin 41, which penetrate the outer disk portion 27A so as to communicate between the left and right sides in the axial direction, and the through holes 27b are formed at equal intervals around the circumference of the driven gear 27.

[0077] A release pin 41 is inserted into the through-hole 27b from the right side and disposed so that its tip protrudes to the left side. As a result, the pressing plate 32 is connected to the driven gear 27 by the release pin 41, and the pressing plate 32 rotates integrally with the driven gear 27.

[0078] The disc spring 33 is large enough to surround the rotating shaft, and is arranged to the right of the pressure plate 32 with its outer end on the left and its inner end on the right, and its outer end is in contact with the pressure plate 32, urging the pressure plate 32 toward the transmission 3.

[0079] The release pin 41 is inserted through the through hole 27b so as to be movable in the direction of the rotational axis, and moves in the direction of the rotational axis integrally with the pressure plate 32. The release pin 41 receives the biasing force of the disc spring 33 via the pressure plate 32 and is pressed toward the transmission 3.

[0080] The spring fixing flange 34 has a cylindrical portion that passes through the inner diameter of the inner end of the disc spring 33 and extends axially, and the right edge of the cylindrical portion is wider than the inner diameter of the disc spring 33, pressing the inner end of the disc spring 33 from the right side toward the driven gear 27.

[0081] The disc spring 33 is attached in a pre-loaded state by being pressed against the spring fixing flange 34, and generates a biasing force that biases the pressure plate 32 toward the transmission 3 with the inner end serving as a fulcrum.

[0082] The spring fixing flange 34 is placed on the outer disc portion 27A of the driven gear 27 radially inward of the disc spring 33 so as to sandwich a seal member therebetween, and is fastened to the inner disc portion 27C with bolts from the internal combustion engine 1 side.

[0083] The tightening point of this bolt is arranged between the work holes for the plurality of bolts 9B, similar to the tightening point of bolt 9C. The tightening point of this bolt can be set to a position coaxial with bolt 9C to improve workability.

[0084] The input-side friction plates 30 and the output-side friction plates 31 are arranged alternately in the direction of the central axis of rotation. The input-side friction plates 30 and the output-side friction plates 31 are capable of contacting each other at their contact portions 30a and 31a, with the outer protrusions 30b positioned radially outward from the contact portions 30a and 31a and the inner protrusions 31b positioned radially inward from the contact portions 30a and 31a.

[0085] The biasing member 28 is a member that maintains the state in which the clutch input member 26 and the driven gear 27 are connected via the input side friction plates 30 and the output side friction plates 31, and biases the input side friction plates 30 and the output side friction plates 31 to press them against the driven gear 27 so that the input side friction plates 30 and the output side friction plates 31 are sandwiched between the input side friction plates 30 and the driven gear 27. The wet clutch 25 of this embodiment is a normally closed type.

[0086] When the input side friction plate 30 and the output side friction plate 31 come into contact with each other and generate friction force, power can be transmitted between the clutch input member 26 and the driven gear 27 via the input side friction plate 30 and the output side friction plate 31.

[0087] As a result, the power of the internal combustion engine 1 is transmitted to the flywheel 3C via the damper input member 22, the coil spring 24, the damper output member 23, the clutch input member 26, the input side friction plate 30, the output side friction plate 31 and the driven gear 27.

[0088] Furthermore, when the motor generator 2 is driven, the power of the motor generator 2 is transmitted to the flywheel 3C via the drive shaft 2A, the drive gear 2B, the driven gear 27, and the driven gear 27. In other words, the motor generator 2 can transmit the power of the motor generator 2 to the flywheel 3C without going through the wet clutch 25.

[0089] A bearing holding flange 13 is attached to the left case portion 10B. The bearing holding flange 13 has a disk portion 13A that abuts against the inner wall surface of the left case portion 10B and a cylindrical portion 13B that extends cylindrically from the radial inner end of the disk portion 13A toward the driven gear 27 side (the internal combustion engine 1 side), and the disk portion 13A is fixed to the left case portion 10B with bolts (not shown).

[0090] As shown in Figure 3, the case 10 houses the release mechanism 36, and the release mechanism 36, wet clutch 25, and damper 21 are arranged in the order of release mechanism 36, wet clutch 25, and damper 21 from the transmission 3 side in the direction of the central axis of rotation.

[0091] The release mechanism 36 is disposed so as to enter the inner diameter side of the teeth portion 27a of the driven gear 27. In other words, the release mechanism 36 is disposed so as to be surrounded by the teeth portion 27a of the driven gear 27.

[0092] The release mechanism 36 includes a cam plate 37 , a ball 38 , a thrust plate 39 , a release bearing 40 , and a release pin 41 .

[0093] The cam plate 37, balls 38, and thrust plate 39 are arranged in the same radial position as the input side friction plate 30 and the output side friction plate 31, and in the axial position they are arranged in the order thrust plate 39, balls 38, and cam plate 37 from the driven gear 27 side.

[0094] The cam plate 37 is rotated within a certain range around the central axis of rotation by a clutch actuator (not shown).

[0095] A plurality of cam grooves 37a are formed on the surface of the cam plate 37 facing the thrust plate 39, and the cam grooves 37a are arranged at regular intervals in the circumferential direction of the cam plate 37.

[0096] Each cam groove 37a extends in the circumferential direction of the cam plate 37 (the rotational direction of the internal combustion engine 1), and has an inclined surface whose depth in the direction of the rotational axis becomes shallower from one end to the other end in the rotational direction of the internal combustion engine 1. In other words, the depth of the cam groove 37a in the direction of the rotational axis changes from one side to the other side in the circumferential direction.

[0097] A cam groove 39a is formed in the thrust plate 39, and a ball 38 is accommodated in the cam groove 39a. The cam groove 39a is formed in a hemispherical shape so that the ball 38 only rolls without moving in the circumferential direction.

[0098] The thrust plate 39 is engaged in the rotational direction with a pin (not shown) fixed to the bearing holding flange 13, so that it is non-rotatable but movable in the direction of the rotational axis.

[0099] The outer ring of the release bearing 40 is fixed to the cam plate 37 and moves integrally with the cam plate 37 in the direction of the rotational axis.

[0100] The inner ring of the release bearing 40 is in contact with the release pin 41, and transmits the movement of the cam plate 37 in the direction of the rotation center axis to the release pin 41, thereby allowing the release pin 41 to move in the axial direction.

[0101] The release bearing 40 moves the release pin 41 in the direction of the central axis of rotation while allowing the release pin 41, which rotates integrally with the driven gear 27, to rotate due to the relative rotation of the outer ring and inner ring. In other words, the release bearing 40 abuts against the wet clutch 25 (more specifically, the biasing member 28) in the direction of the central axis of rotation.

[0102] When the clutch actuator rotates the cam plate 37 from one side to the other (clutch disengagement direction), the cam groove 37a moves relative to the ball 38, and the ball 38 moves from a position on the deep inclined surface to a position on the shallow inclined surface, increasing the amount by which the ball 38 protrudes from the cam plate 37.

[0103] This pushes the cam plate 37 towards the driven gear 27. When the cam plate 37 moves towards the driven gear 27, the release bearing 40 presses the release pin 41 towards the internal combustion engine 1, causing the release pin 41 to move towards the internal combustion engine 1.

[0104] As the release pin 41 moves toward the internal combustion engine 1, the pressure plate 32 moves toward the internal combustion engine 1 against the biasing force of the disc spring 33, and the pressure from the pressure plate 32 no longer acts on the input side friction plate 30 and the output side friction plate 31.

[0105] As a result, a gap is created between the input side friction plate 30 and the output side friction plate 31, the wet clutch 25 is disengaged, and the power transmitted from the internal combustion engine 1 to the driven gear 27 is interrupted.

[0106] On the other hand, in the release mechanism 36, when the clutch actuator rotates the cam plate 37 from one side to the other (clutch connection direction), the cam groove 37a moves relative to the ball 38, and the ball 38 moves from the shallow inclined surface position to the deep inclined surface position, thereby reducing the amount by which the ball 38 protrudes from the cam plate 37.

[0107] At this time, the pressing plate 32, release bearing 40, and cam plate 37 are pressed toward the transmission 3 by the biasing force of the disc spring 33, and the pressing plate 32 moves from the internal combustion engine 1 side to the transmission 3 side.

[0108] As a result, the friction member is pressed toward the transmission 3 by the pressure plate 32, and the input side friction plate 30 and the output side friction plate 31 are sandwiched between the pressure plate 32 and the driven gear 27 (outer disc portion 27A), generating a strong friction force. As a result, the wet clutch 25 is engaged, and the power of the internal combustion engine 1 is transmitted to the driven gear 27 via the wet clutch 25.

[0109] Furthermore, when the wet clutch 25 is engaged, the damper output member 23 is connected to the flywheel 3C (i.e., the transmission 3) via the clutch input member 26, the input side friction plate 30, the output side friction plate 31 and the driven gear 27.

[0110] When rotational fluctuations (torque fluctuations) occur in the internal combustion engine 1 while the wet clutch 25 is engaged, the coil spring 24 elastically deforms in the rotational direction of the damper 21, causing the damper input member 22 and the damper output member 23 to rotate relative to each other, thereby absorbing the rotational fluctuations in the internal combustion engine 1.

[0111] In the power transmission device 4 of this embodiment, during engine running in which the hybrid vehicle is driven by the power of the internal combustion engine 1, the gear change clutch 3A of the transmission 3 and the wet clutch 25 are in an engaged state.

[0112] As a result, the power of the internal combustion engine 1 is transmitted to the flywheel 3C via the damper input member 22, coil spring 24, damper output member 23, clutch input member 26, input side friction plate 30, output side friction plate 31 and driven gear 27, and then transmitted from the flywheel 3C to the input shaft 3D via the speed-changing clutch 3A.

[0113] During motor running, in which the internal combustion engine 1 is stopped and the hybrid vehicle is driven by the power of the motor generator 2, the gear change clutch 3A of the transmission 3 is connected and the wet clutch 25 is disconnected.

[0114] As a result, the power of the motor generator 2 is transmitted to the flywheel 3C via the drive shaft 2A, drive gear 2B and driven gear 27, and then transmitted from the flywheel 3C to the input shaft 3D via the speed-changing clutch 3A.

[0115] During hybrid running, in which the hybrid vehicle is driven by the power of the internal combustion engine 1 and the motor generator 2, the gear change clutch 3A of the transmission 3 and the wet clutch 25 are brought into an engaged state.

[0116] As a result, power is transmitted from the internal combustion engine 1 and the motor generator 2 to the transmission 3 via a power transmission path similar to the power transmission path from the internal combustion engine 1 to the transmission 3 and the power transmission path from the motor generator 2 to the transmission 3 described above.

[0117] In hybrid driving, the internal combustion engine 1 can be operated in a fuel-efficient state, and the driving force of the motor generator 2 can improve the acceleration performance of the hybrid vehicle.

[0118] Furthermore, when the hybrid vehicle is decelerating (regenerating), the gear change clutch 3A of the transmission 3 is connected and the wet clutch 25 is disconnected, thereby completely disconnecting the internal combustion engine 1 from the drive wheels 6L, 6R.

[0119] As a result, the power of the drive wheels 6L, 6R is transmitted to the transmission 3 via the drive shafts 5L, 5R and the differential, and then transmitted from the input shaft 3D of the transmission 3 to the motor generator 2 via the flywheel 3C, driven gear 27, drive gear 2B and drive shaft 2A, thereby causing the motor generator 2 to regenerate power.

[0120] When the hybrid vehicle is decelerating with the wet clutch 25 in a disengaged state and the internal combustion engine 1 and the drive wheels 6L, 6R completely separated, no engine braking occurs, so the energy loss due to engine braking is reduced and the power from the transmission 3 during deceleration is transmitted to the motor generator 2, allowing for efficient power regeneration.

[0121] In the hybrid vehicle of this embodiment, when the gear-change clutch 3A of the transmission 3 is disengaged and the wet clutch 25 is engaged, the internal combustion engine 1 and the motor generator 2 can be connected in a manner that allows driving force to be transmitted, so that electricity can be generated by the motor generator 2 without the vehicle being driven.

[0122] In this embodiment, driven gear 27 is formed to have a larger diameter than release mechanism 36. Specifically, of the components that make up release mechanism 36, cam plate 37 and thrust plate 39 are large-diameter components, and driven gear 27 is formed to have a larger diameter than cam plate 37 and thrust plate 39.

[0123] The driven gear 27 and the release mechanism 36 are disposed at the same position in the direction of the central axis of rotation, and the release mechanism 36 is disposed inward of the teeth 27a of the driven gear 27. In other words, the release mechanism 36 is disposed so as to fit inside the teeth 27a of the driven gear 27, thereby making the device more compact.

[0124] As shown in Figure 3, a bearing 11E is provided between the outer periphery of the outer cylindrical portion 27B of the driven gear 27 and the inner periphery of the cylindrical portion 13B of the bearing holding flange 13, and the driven gear 27 is rotatably supported on the bearing holding flange 13 via the bearing 11E.

[0125] A snap ring 42 is fitted onto the outer periphery of the outer cylindrical portion 27B, and the left end of the inner ring of the bearing 11E abuts against the snap ring 42 to prevent it from slipping out of the outer cylindrical portion 27B.

[0126] A step 27f is formed at the left end of outer cylindrical portion 27B, and the right end of the inner ring of bearing 11E abuts against step 27f for positioning. In other words, bearing 11E is positioned and attached to driven gear 27 with its inner ring attached between snap ring 42 and step 27f.

[0127] A bent portion 13a is formed at the end of the right end of the cylindrical portion 13B by bending the right end of the cylindrical portion 13B radially inward, and the right end of the outer ring of the bearing 11E abuts against the bent portion 13a.

[0128] The left end of the outer ring of bearing 11E abuts against the inner end of left case portion 10B. That is, the outer ring of bearing 11E abuts against bent portion 13a and the inner end of left case portion 10B, and is unable to move in the direction of the central axis of rotation.

[0129] As a result, the driven gear 27 is rotatably supported by the left case portion 10B but is immovable in the direction of the rotation axis.

[0130] In this structure, the outer ring of bearing 11E is first attached to left case portion 10B, and then outer cylindrical portion 27B of driven gear 27 is inserted into the inner ring of bearing 11E to attach snap ring 42. This attachment is possible because oil seal 12C, which will be described later, is located next to snap ring 42.

[0131] The case 10 houses an oil guide (not shown), which supplies lubricating oil scooped up by the driven gear 27 to the meshing portion between the drive gear 2B and the tooth portion 27a.

[0132] As shown in FIG. 3, an annular oil seal 12B is provided between the outer periphery of the shaft mounting portion 22A of the damper input member 22 and the inner end of the right case portion 10A.

[0133] An oil seal 12C is provided between the outer periphery of the outer cylindrical portion 27B of the driven gear 27 and the inner end of the left case portion 10B.

[0134] An oil seal 12D is provided between the outer periphery of the shaft attachment portion 22A and the spring fixing flange . That is, the oil seal 12D is provided inside the spring fixing flange .

[0135] Bearing 11C, which is provided between shaft portion 27D of driven gear 27 and damper input member 22, is a sealed type bearing, and is structured so that a lubricant is sealed inside bearing 11C. The outer ring and inner ring of bearing 11C are attached between shaft attachment portion 22A and shaft portion 27D of driven gear 27, respectively.

[0136] Oil seals 12B, 12C, and 12D are disposed radially outward of the multiple threaded holes 1a of crankshaft 1B and the multiple through holes 22a of shaft mounting portion 22A, and lubricating oil is sealed inside case 10. Therefore, the inside of case 10 is liquid-tightly sealed by oil seals 12B, 12C, and 12D.

[0137] Next, the effects of the power transmission device 4 for the hybrid vehicle of this embodiment will be described. The power transmission device 4 of the hybrid vehicle of this embodiment is arranged between the internal combustion engine 1 and the transmission 3, transmits power from the motor generator 2 to the transmission 3, and has a wet clutch 25 that can connect and disconnect power between the internal combustion engine 1 and the transmission 3.

[0138] The wet clutch 25 has a clutch input member 26 to which power is transmitted from the internal combustion engine 1, a driven gear 27 that is connected to the shaft portion 3a of the transmission 3 and that operates in conjunction with the motor generator 2, and an input side friction plate 30 and an output side friction plate 31 that connect and disconnect the clutch input member 26 and the driven gear 27.

[0139] The wet clutch 25 also includes a pressure plate 32 that is biased by a disc spring 33 to press the input side friction plate 30 and the output side friction plate 31 against the driven gear 27, thereby connecting the clutch input member 26 and the driven gear 27 via the input side friction plate 30 and the output side friction plate 31.

[0140] The input side friction plates 30 rotate integrally with the clutch input member 26, and the output side friction plates 31 are arranged alternately with the input side friction plates 30. The pressure plate 32 has a plurality of through holes 32a that penetrate the pressure plate 32 in the radial direction.

[0141] In addition, the output side friction plate 31 has a plurality of inner protrusions 31b that protrude inward from the inner end of the output side friction plate 31 and engage with the through holes 32a, and the pressure plate 32 and the output side friction plate 31 rotate together.

[0142] In this way, by engaging the output side friction plate 31 with the pressure plate 32, the pressure plate 32 can be given the function of holding the output side friction plate 31 and the function of connecting and separating the input side friction plate 30 and the output side friction plate 31.

[0143] This eliminates the need to provide the driven gear 27, which functions as the clutch output member, with a plate holding portion for holding the output-side friction plate 31. In other words, instead of this plate holding portion, the pressing plate 32 can be given the function of the plate holding portion.

[0144] This eliminates the need for the plate holders provided inside the input friction plate 30 and the output friction plate 31, and allows the diameters of the inner ends of the input friction plate 30 and the output friction plate 31 to be reduced, thereby expanding the contact surface area inward and increasing the area of ​​the contact portion 30 a of the input friction plate 30 and the contact portion 31 a of the output friction plate 31.

[0145] As a result, even if the number of input side friction plates 30 and output side friction plates 31 is reduced, a decrease in the friction force between the input side friction plates 30 and the output side friction plates 31 can be suppressed, and the axial length of the power transmission device 4 in the direction of the central axis of rotation can be shortened by reducing the number of input side friction plates 30 and output side friction plates 31.

[0146] In this way, the power transmission device 4 of this embodiment can increase the contact area between the input side friction plate 30 and the output side friction plate 31, while also achieving a reduction in size of the power transmission device 4.

[0147] Furthermore, the power transmission device 4 of the hybrid vehicle of this embodiment has a release pin 41 that is attached to the driven gear 27 so as to be freely movable in the direction of the rotation axis and connects the pressure plate 32 to the driven gear 27, and when the release pin 41 moves toward the internal combustion engine 1 (one side) in the axial direction of the rotation axis due to the biasing force of the disc spring 33, the input side friction plate 30 and the output side friction plate 31 are separated from each other, and the connection between the clutch input member 26 and the driven gear 27 is released.

[0148] This allows the release pin 41 to attach the pressure plate 32 to the driven gear 27 and disconnect the clutch input member 26 and the driven gear 27 by releasing the connection between the input side friction plate 30 and the output side friction plate 31.

[0149] In other words, since the release pin 41 can serve two functions, the number of parts in the release mechanism 36 can be reduced, and the release mechanism 36 can be made smaller.

[0150] Furthermore, according to the power transmission device 4 of the hybrid vehicle of this embodiment, the release pin 41 moves toward the transmission 3 (the other side) in the direction of the central axis of rotation due to the biasing force of the disc spring 33, whereby the input side friction plate 30 and the output side friction plate 31 come into contact with each other, connecting the clutch input member 26 and the driven gear 27.

[0151] As a result, the operation of bringing the input side friction plate 30 and the output side friction plate 31 into contact with each other to connect the clutch input member 26 and the driven gear 27 can be performed via the release pin 41. Therefore, there is no need to provide a new portion to receive the biasing force of the disc spring 33.

[0152] This results in stable operation of the wet clutch 25. In addition, the number of parts in the release mechanism 36 can be further reduced, and the release mechanism 36 can be made even more compact.

[0153] Furthermore, according to the power transmission device 4 for a hybrid vehicle of this embodiment, the biasing member 28 has an annular disc spring 33 whose outer end comes into contact with the pressure plate 32 and biases the pressure plate 32 so as to press the input side friction plate 30 and the output side friction plate 31 against the driven gear 27 via the pressure plate 32, and a disk-shaped spring fixing flange 34 that fits onto the inner end of the disc spring 33 and attaches the disc spring 33 to the driven gear 27.

[0154] In addition, the spring fixing flange 34 is attached to the driven gear 27 radially inward of the disc spring 33 .

[0155] In this way, the spring fixing flange 34 is fitted onto the inner end of the disc spring 33 and attached to the driven gear 27 radially inward of the disc spring 33, so that the outer end of the spring fixing flange 34 can be overlapped radially on the inner end of the disc spring 33.

[0156] Therefore, the radial dimension of the spring fixing flange 34 can be reduced, thereby making the spring fixing flange 34 more compact, and the input side friction plate 30 and the output side friction plate 31 can be extended further radially inward.

[0157] As a result, the friction area between the input side friction plate 30 and the output side friction plate 31 can be further increased, and the operation of the wet clutch 25 can be made even more stable.

[0158] Furthermore, according to the power transmission device 4 for a hybrid vehicle of this embodiment, the oil seal 12D is disposed inside the spring fixing flange .

[0159] This makes it possible to easily secure a mounting location for the oil seal 12D, eliminating the need to add a new space for arranging the oil seal 12D, thereby enabling the power transmission device 4 to be made even more compact.

[0160] While an embodiment of the present invention has been disclosed, it will be apparent to one skilled in the art that modifications may be made thereto without departing from the scope of the present invention, and it is intended that all such modifications and equivalents be included in the following claims. [Explanation of symbols]

[0161] 1. Internal combustion engine 2 Motor generator (rotating electric machine) 3-speed 3a Shaft (rotating axis) 4 Power transmission device 25 Wet clutch (clutch) 26 Clutch input member 27 Driven gear (clutch output member) 28 biasing member 30 Input side friction plate (friction member, first friction plate) 31 Output side friction plate (friction member, second friction plate) 31b Inner protrusion (engaging part) 32 Pressing plate (pressing member) 32a through hole 33 Disc spring (biasing member) 34 Spring fixing flange (biasing member) 41 Release pin

Claims

1. A power transmission device for a hybrid vehicle, comprising a clutch disposed between an internal combustion engine and a transmission, transmitting power from a rotating electric machine to the transmission, and capable of connecting and disconnecting power between the internal combustion engine and the transmission, The clutch is a clutch input member to which power is transmitted from the internal combustion engine; a clutch output member connected to a rotary shaft of the transmission and interlocking with the rotary electric machine; a friction member that connects and disconnects the clutch input member and the clutch output member; a pressing member that is biased by a biasing member to press the friction member against the clutch output member, thereby connecting the clutch input member and the clutch output member via the friction member, the friction member includes first friction plates that rotate integrally with the clutch input member and second friction plates that are arranged alternately with the first friction plates, the pressing member has a plurality of through holes that penetrate the pressing member in a radial direction, the second friction plate has a plurality of engaging portions that protrude radially inward from an inner end portion of the second friction plate and engage with the through holes, 10. A power transmission device for a hybrid vehicle, wherein the pressing member and the second friction plate rotate integrally.

2. a release pin attached to the clutch output member so as to be movable in the axial direction of the rotary shaft, the release pin connecting the pressing member to the clutch output member; 2. The power transmission device for a hybrid vehicle according to claim 1, wherein the release pin moves to one side in the axial direction of the rotating shaft against the biasing force of the biasing member, causing the first friction plate and the second friction plate to separate from each other, thereby releasing the connection between the clutch input member and the clutch output member.

3. 3. The power transmission device for a hybrid vehicle according to claim 2, wherein the release pin moves to the other side in the axial direction of the rotating shaft due to the biasing force of the biasing member, thereby bringing the first friction plate and the second friction plate into contact with each other, thereby connecting the clutch input member and the clutch output member.

4. The biasing member is an annular disc spring whose outer end contacts the pressing member and biases the pressing member so as to press the first friction plate and the second friction plate against the clutch output member via the pressing member; a disk-shaped spring fixing flange that fits onto an inner end of the disc spring and attaches the disc spring to the clutch output member, 4. The power transmission device for a hybrid vehicle according to claim 2, wherein the spring fixing flange is attached to the clutch output member radially inward of the disc spring.

5. 5. The power transmission device for a hybrid vehicle according to claim 4, wherein an oil seal is disposed inside the spring fixing flange.

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