JP2019127963A - Power transmission device - Google Patents

Abstract

To reduce loss torque resulting from the drag resistance of a multiplate wet clutch.SOLUTION: A multiplate wet clutch 200 comprises: a driven plate (first plate) 206 arranged at a pinion gear shaft 136; a drive plate (second plate) 204 arranged at a propeller shaft 126, opposing the first plate in an axial direction, and including a plurality of split plates 204D which are split in a rotation direction; and a transfer piston 210 for driving the first plate and the second plate in the axial direction between a contact position in which the first plate and the second plate contact with each other, and a separation position in which the first plate and the second plate separate from each other. The split plates are constituted so as to be movable to a radial direction of the propeller shaft, and an opposing area in which the first plate and the second plate oppose each other in the axial direction at the contact position is larger than an opposing area in which the first plate and the second plate oppose each other in the axial direction at the separation position.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a power transmission device.

  Patent Document 1 discloses a wet multi-plate clutch in which a plurality of drive plates and driven plates are alternately combined in a state of being immersed in lubricating oil.

JP, 2015-4433, A

  However, in the wet multi-plate clutch of Patent Document 1, the areas of the opposed regions in which the drive plate and the driven plate face each other in the axial direction are always constant. For this reason, the wet multi-plate clutch of Patent Document 1 has a problem that the loss torque due to the drag resistance of the wet multi-plate clutch is large when not engaged.

  Then, an object of this invention is to reduce the loss torque resulting from the drag resistance of a wet multi-plate clutch.

  In order to solve the above problems, a power transmission device according to the present invention is provided on a first rotation shaft, and a first plate disposed in a lubricating oil supply space to which lubricating oil is supplied, and a second plate. A plurality of divided plates that are axially opposed to the first plate and divided in the rotational direction, and a second plate disposed in the lubricating oil supply space, and the first plate and the second plate are in contact with each other And a drive unit that drives the first plate and the second plate in the axial direction between a contact position where the first plate and the second plate are separated from each other, and the divided plate Is configured to be movable in the radial direction of the second rotating shaft, and the first plate and the second plate are opposed to each other in the axial direction in the spaced position, and the first position in the contact position. plate Towards the opposite area between the second plate facing the axial direction becomes large.

  The first rotation shaft includes a plurality of first plates, the second rotation shaft includes a plurality of second plates, and the plurality of first plates and the plurality of second plates alternate in the axial direction. May be arranged.

  The drive unit may include a piston that presses the dividing plate in the axial direction by moving in the axial direction.

  A cylindrical portion having an inner peripheral surface that engages with the divided plate, and the cylindrical portion includes an inclined portion in which an inner diameter of the inner peripheral surface decreases in a direction in which the driving unit presses the divided plate. You may have.

  The driving unit may move the piston in the axial direction by hydraulic pressure, and move the divided plate in the radial direction by hydraulic pressure for moving the piston.

  According to the present invention, it is possible to reduce the loss torque resulting from the drag resistance of the wet multi-plate clutch.

It is a figure showing composition of a car. It is the schematic which shows the structure of the coupling in this embodiment. It is the schematic which shows the structure of the wet multi-plate clutch in this embodiment. It is a figure which shows the engagement state of the division | segmentation plate and the rectilinear advance groove | channel formed in a taper part.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values and the like shown in this embodiment are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. Do.

  FIG. 1 is a diagram showing the configuration of a car 100. As shown in FIG. The automobile 100 is a four-wheel drive vehicle capable of switching between 4WD (four-wheel drive) traveling that drives the front and rear wheels and 2WD (two-wheel drive) traveling that drives either the front wheels or the rear wheels. The automobile 100 of the present embodiment drives the front wheels during 2WD travel, but is not limited to this, and may drive the rear wheels.

  In the present embodiment, a plug-in hybrid vehicle (PHEV) that can be charged with electric energy directly from an external commercial outlet and can be switched between 2WD travel and 4WD travel is described as the automobile 100, in particular. . However, if the vehicle can travel by switching between 2WD travel and 4WD travel, the drive source may be either one or both of the engine and the motor; electric vehicles (EVs), engine cars, non plug-in Various vehicle types such as a hybrid vehicle (hybrid vehicle) can be adopted. Here, the configuration related to the feature of the present embodiment will be described in detail, and the description of the configuration unrelated to the feature of the present embodiment will be omitted.

  The engine 110 is composed of a gasoline engine or a diesel engine. The engine 110 obtains driving power by burning fuel (gasoline, diesel, etc.) supplied from the fuel tank 112. The engine 110 transmits the obtained driving force to the transmission 116 via the clutch 114. The engine 110 is connected to an electronic control unit (hereinafter simply referred to as an ECU) 118, and the driving force is adjusted based on a control command of the ECU 118.

  The motor 120 is disposed coaxially with the engine 110. The motor 120 obtains driving force by the electric power supplied from the battery 124 via the inverter 122. Motor 120 transmits the obtained driving force to transmission 116. The motor 120 also functions as a generator at a timing when no power is supplied. The electric power generated by the motor 120 is stored in the battery 124 via the inverter 122. The inverter 122 is connected to the ECU 118, and the supplied electric power (driving force of the motor 120) is adjusted based on a control command of the ECU 118.

  The driving force output from a driving source such as the engine 110 or the motor 120 is adjusted in torque, rotational speed and rotational direction by the transmission 116 and transmitted to the propeller shaft 126. The driving force transmitted to the propeller shaft 126 is transmitted to the front wheel 132 via the front differential gear 128 and the front drive shaft 130. Further, during 4WD traveling, the driving force transmitted to the propeller shaft 126 is also transmitted to the rear wheel 142 via the coupling 134, the pinion gear shaft 136, the rear differential gear 138, and the rear drive shaft 140.

  The coupling 134 is provided between the drive source and the rear differential gear 138, and is configured to be able to interrupt the transmission of the drive force between the drive source and the rear differential gear 138. The coupling 134 is configured to be able to adjust the ratio of the torque (driving force) transmitted to the front wheels 132 and the torque (driving force) transmitted to the rear wheels 142. In the present embodiment, the front wheel 132 obtains driving force directly from the transmission 116, and the rear wheel 142 obtains driving force via the coupling 134. However, the rear wheel 142 may obtain drive directly from the transmission 116, and the front wheel 132 may obtain drive via the coupling 134. In the present embodiment, the coupling 134 is tightened when a control pressure (hydraulic pressure) is supplied from a hydraulic pressure supply device (hydraulic circuit) (not shown), and is released when the control pressure is discharged. It is a clutch.

  The control unit 144 is configured by a semiconductor integrated circuit including a central processing unit (CPU), a ROM storing programs and the like, and a RAM as a work area. The control unit 144 centrally controls the entire vehicle 100. Further, in the present embodiment, the control unit 144 also functions as the drive switching unit 162 and the coupling control unit 164. The control unit 144 is connected to various sensors such as a shift position sensor 146, a brake pedal sensor 148, a vehicle speed sensor 150, an accelerator pedal sensor 152, and the like, and takes in detection signals of the respective sensors.

  The shift position sensor 146 detects whether the shift range of the transmission 116 is in forward range (D range), reverse range (R range), neutral range (N range), or parking range (P range). . The brake pedal sensor 148 detects a depression amount (hydraulic pressure) of a brake pedal (not shown). Vehicle speed sensor 150 detects the speed of automobile 100. The accelerator pedal sensor 152 detects the depression amount (hydraulic pressure) of the accelerator pedal (not shown). The control unit 144 controls the driving force of the engine 110 and the motor 120 via the ECU 118.

  The drive switching unit 162 switches the drive state (2WD travel, 4WD travel) of the vehicle 100. The drive switching unit 162 switches between 2WD travel and 4WD travel, for example, in response to the 2WD travel or 4WD travel being selected by the driver's operation. Further, the drive switching unit 162 may automatically switch between 2WD traveling and 4WD traveling according to the traveling state of the automobile 100 (for example, the vehicle speed of the automobile 100, the amount of depression of the accelerator pedal, etc.).

  The coupling control unit 164 drives the coupling 134 while the 4WD traveling is being performed, and adjusts the distribution of the driving force of the front wheel 132 and the rear wheel 142 according to the traveling state to optimize the power to the rear wheel 142. Make a transmission. The coupling control unit 164 stops driving the coupling 134 and cuts off power transmission to the rear wheel 142 while 2WD traveling is being performed.

  FIG. 2 is a schematic diagram showing the configuration of the coupling 134 in the present embodiment.

  The coupling 134 has a transfer case C. In this transfer case C, an end of a propeller shaft (second rotating shaft) 126, an end of a pinion gear shaft (first rotating shaft) 136, a wet multi-plate clutch ( A power transmission device) 200 is accommodated. The pinion gear shaft 136 is arranged coaxially with the propeller shaft 126. In the transfer case C, the end of the pinion gear shaft 136 is rotatably provided relative to the end of the propeller shaft 126. The wet multi-plate clutch 200 is disposed between the end of the propeller shaft 126 and the end of the pinion gear shaft 136.

  The wet multi-plate clutch 200 includes a clutch drum 202, a drive plate (second plate) 204, a driven plate (first plate) 206, a clutch hub 208, and a transfer piston (drive unit) 210.

  The clutch drum 202 is provided at the end of the propeller shaft 126, and the clutch hub 208 is provided at the end of the pinion gear shaft 136. The clutch drum 202 and the clutch hub 208 are non-contact and are configured to be rotatable relative to each other. The clutch drum 202 has a disc-shaped first disc portion 202a, a cylindrical portion (first cylindrical portion) 202b, and a disc-shaped second disc portion 202c.

  An inner peripheral end of the first disk portion 202 a is connected to an end (outer peripheral surface) of the propeller shaft 126. One end of the cylindrical portion 202b is connected to the outer peripheral end of the first disc portion 202a, and is disposed on the pinion gear shaft 136 side of the first disc portion 202a. An outer peripheral end of the second disk portion 202c is connected to the other end of the cylindrical portion 202b, and the second disk portion 202c is disposed on the pinion gear shaft 136 side of the cylindrical portion 202b. The inner diameter of the cylindrical portion 202b is larger than the inner diameter of the first disk portion 202a (the outer diameter of the propeller shaft 126) and the inner diameter of the second disk portion 202c.

  The clutch hub 208 has a disc-shaped disc portion 208 a and a cylindrical portion 208 b. The inner peripheral end of the disk portion 208 a is connected to the end (outer peripheral surface) of the pinion gear shaft 136. One end of the cylindrical portion 208b is connected to the outer peripheral end of the disc portion 208a, and is disposed on the propeller shaft 126 side of the disc portion 208a. The inner diameter of the cylindrical portion 208b is larger than the inner diameter of the disk portion 208a (the outer diameter of the pinion gear shaft 136).

  The inner diameter of the second disk portion 202c is larger than the outer diameter of the disk portion 208a and the outer diameter of the cylindrical portion 208b. The disc portion 208a and the cylindrical portion 208b are disposed closer to the pinion gear shaft 136 than the first disc portion 202a. The disk portion 208a is arranged at a position where at least a portion thereof overlaps with the second disk portion 202c in the axial direction of the propeller shaft 126 (hereinafter simply referred to as the axial direction). The cylindrical portion 208b is disposed at a position where at least a portion overlaps the cylindrical portion 202b in the axial direction. Therefore, the inner peripheral surface of the cylindrical portion 202b of the clutch drum 202 faces the outer peripheral surface of the cylindrical portion 208b of the clutch hub 208 in the radial direction of the propeller shaft 126 (hereinafter simply referred to as the radial direction).

  A plurality of drive plates 204 and a plurality of driven plates 206 are arranged in a facing region where the inner peripheral surface of the cylindrical portion 202b of the clutch drum 202 and the outer peripheral surface of the cylindrical portion 208b of the clutch hub 208 face each other.

  The plurality of drive plates 204 are spline-fitted to the inner peripheral surface of the cylindrical portion 202b of the clutch drum 202, and are configured to be movable in the axial direction on the inner peripheral surface of the cylindrical portion 202b. The plurality of driven plates 206 are spline-fitted to the outer peripheral surface of the cylindrical portion 208b of the clutch hub 208, and are configured to be movable in the axial direction on the outer peripheral surface of the cylindrical portion 208b.

  At least some of the plurality of drive plates 204 are opposed to the plurality of driven plates 206 in the axial direction. In the present embodiment, the inner diameter sides of the plurality of drive plates 204 are opposed to the outer diameter sides of the plurality of driven plates 206 in the axial direction. The plurality of drive plates 204 and the plurality of driven plates 206 move in the axial direction to switch between a contact state (fastening state) in contact with each other and a noncontact state (nonfastening state) in which the drive plates 204 and the driven plates 206 are not in contact with each other.

  The plurality of drive plates 204 and the plurality of driven plates 206 do not rotate relative to each other in the contact state (fastened state) but relatively rotate in the non-contact state (non-fastened state). The plurality of drive plates 204 and the plurality of driven plates 206 are disposed in the lubricating oil supply space to which the lubricating oil is supplied, and are alternately combined and arranged in the axial direction while being immersed in the lubricating oil.

  The clutch drum 202 and the plurality of drive plates 204 rotate integrally with the propeller shaft 126 when the propeller shaft 126 rotates. Further, the clutch hub 208 and the plurality of driven plates 206 rotate integrally with the pinion gear shaft 136 when the pinion gear shaft 136 rotates.

  The transfer piston 210 is provided to variably control the torque transmission capacity by variably applying a fastening force to the wet multi-plate clutch 200 (the plurality of drive plates 204 and the plurality of driven plates 206). The transfer piston 210 is provided in the clutch drum 202 and is disposed between the first disk portion 202 a and the drive plate 204.

  The transfer piston 210 is configured to be movable in the axial direction within the clutch drum 202. One end 210a of the transfer piston 210 faces the drive plate 204 in the axial direction. A hydraulic chamber 212 is formed between the clutch drum 202 and the transfer piston 210. The hydraulic chamber 212 communicates with a hydraulic circuit (not shown) through the through hole T of the first disk portion 202a.

  The hydraulic oil is introduced into the hydraulic chamber 212 from a hydraulic circuit (not shown). Further, the hydraulic oil in the hydraulic chamber 212 is discharged to a hydraulic circuit (not shown). The transfer piston 210 moves in the axial direction by the hydraulic pressure of the hydraulic oil introduced into the hydraulic chamber 212. The hydraulic pressure of the hydraulic oil introduced into the hydraulic chamber 212 is controlled by the coupling control unit 164.

  When the hydraulic oil is introduced into the hydraulic chamber 212, the transfer piston 210 moves in the approaching direction (hereinafter also referred to as the pinion gear shaft 136 side) close to the plurality of drive plates 204 (the plurality of driven plates 206). The transfer piston 210 presses the drive plate 204 (or the driven plate 206) in the opposing direction of the drive plate 204 and the driven plate 206 according to the hydraulic pressure of the hydraulic fluid. The drive plate 204 (or driven plate 206) moves in the direction in which the transfer piston 210 presses (pinion gear shaft 136 side).

  Further, when the hydraulic oil is discharged from the hydraulic chamber 212, the transfer piston 210 moves in a separation direction (hereinafter also referred to as propeller shaft 126 side) separated from the plurality of drive plates 204 (plurality of driven plates 206). . The drive plate 204 (or the driven plate 206) is released from being pressed by the transfer piston 210 when the transfer piston 210 moves to the propeller shaft 126 side. When the drive plate 204 (or the driven plate 206) is released from the press, it moves toward the moving direction of the transfer piston 210 (propeller shaft 126 side).

  Specifically, when the hydraulic oil is introduced into the hydraulic chamber 212, the transfer piston 210 moves to the pinion gear shaft 136 side. When the transfer piston 210 moves to the pinion gear shaft 136 side, the drive plate 204a arranged closest to the propeller shaft 126 among the plurality of drive plates 204 is pressed to the pinion gear shaft 136 side. When the drive plate 204 a is pressed by the transfer piston 210, the drive plate 204 a comes into contact with the driven plate 206 a adjacent to the pinion gear shaft 136 side and presses it toward the pinion gear shaft 136 side.

  When the driven plate 206a is pressed by the drive plate 204a, the driven plate 206a contacts the drive plate 204b adjacent to the pinion gear shaft 136 to press the same toward the pinion gear shaft 136. When the drive plate 204b is pressed by the driven plate 206a, the drive plate 204b comes into contact with the driven plate 206b adjacent to the pinion gear shaft 136 side, and presses this toward the pinion gear shaft 136 side.

  When the driven plate 206b is pressed by the drive plate 204b, the driven plate 206b contacts the drive plate 204c adjacent to the pinion gear shaft 136 to press the same toward the pinion gear shaft 136. Of the plurality of drive plates 204, the drive plate 204c disposed closest to the pinion gear shaft 136 abuts against a movement restriction member (not shown) when pressed from the driven plate 206b. The drive plate 204c is in contact with the movement restricting member, so that the movement toward the pinion gear shaft 136 is restricted. Further, by restricting the movement of the drive plate 204c, the movement of the drive plates 204a and 204b and the driven plates 206a and 206b is also restricted.

  Thereby, the plurality of drive plates 204 and the plurality of driven plates 206 are axially pressed between the transfer piston 210 and the movement restricting member (not shown), and maintain the state of contact (engagement) with each other. At this time, the wet multi-plate clutch 200 is in the engaged state in which the plurality of drive plates 204 and the plurality of driven plates 206 are engaged. The wet multi-plate clutch 200 transmits torque between the propeller shaft 126 and the pinion gear shaft 136 when in the engaged state.

  On the other hand, when the hydraulic oil is discharged from the hydraulic chamber 212, the transfer piston 210 moves to the propeller shaft 126 side. When the transfer piston 210 moves toward the propeller shaft 126, the transfer piston 210 releases the pressure on the drive plate 204a. When the pressure from the transfer piston 210 is released, the drive plate 204a releases the pressure on the driven plate 206a, releases the contact (engagement) with the driven plate 206a, and separates from the driven plate 206a.

  When the pressure from the drive plate 204a is released, the driven plate 206a releases the pressure on the drive plate 204b, releases the contact (engagement) with the drive plate 204b, and moves away from the drive plate 204b. When the pressure from driven plate 206a is released, drive plate 204b releases the pressure on driven plate 206b, releases contact (engagement) with driven plate 206b, and separates from driven plate 206b.

  When the pressure from the drive plate 204b is released, the driven plate 206b releases the pressure on the drive plate 204c, releases the contact (engagement) with the drive plate 204c, and moves away from the drive plate 204c. When the pressure from the driven plate 206b is released, the drive plate 204c releases contact (engagement) with a movement restriction member (not shown) and moves away from the movement restriction member.

  Thereby, the plurality of drive plates 204 and the plurality of driven plates 206 are separated from each other to release contact (engagement) with each other. At this time, the wet multi-plate clutch 200 is in the non-engaged state (non-engaged state) where the fastening of the plurality of drive plates 204 and the plurality of driven plates 206 is released. The wet multi-plate clutch 200 blocks the transmission of torque between the propeller shaft 126 and the pinion gear shaft 136 when in the disengaged state (non-engaged state).

  Thus, the transfer piston 210 is moved by the hydraulic pressure of the hydraulic fluid to the fastening position where the plurality of drive plates 204 and driven plates 206 fasten. Further, the transfer piston 210 is moved to a disengagement position (non-engagement position) where the plurality of drive plates 204 and driven plates 206 are unfastened by the hydraulic pressure of the hydraulic oil. The transfer piston 210 axially drives the transfer piston 210 between a contact position where the plurality of drive plates 204 and the plurality of driven plates 206 contact and a separation position where the plurality of drive plates 204 and the plurality of driven plates 206 are separated. To do.

  Here, it is desirable that the plurality of drive plates 204 and the plurality of driven plates 206 have large contact areas in contact with each other in order to secure torque transmission capacity at the time of fastening. However, when the contact area at the time of fastening is increased, the opposing regions (facing areas) facing the axial direction of the plurality of drive plates 204 and the plurality of driven plates 206 at the time of non-fastening also increase. If the opposing region becomes large when not fastened, loss torque due to drag resistance of the wet multi-plate clutch 200 becomes large. Therefore, the wet multi-plate clutch 200 of the present embodiment is configured as follows in order to reduce the loss torque at the time of non-engagement while ensuring a predetermined torque transmission capacity at the time of engagement. Below, the structure of the wet multi-plate clutch 200 in this embodiment is explained in full detail.

  FIG. 3 is a schematic view showing the configuration of the wet multi-plate clutch 200 in the present embodiment. FIG. 3A is a view showing the shapes of the drive plate 204 and the driven plate 206 as viewed from the axial direction when not engaged. FIG. 3B is a schematic cross-sectional view showing the positional relationship between the drive plate 204 and the driven plate 206 at the time of non-fastening. FIG. 3C is a diagram illustrating the shapes of the drive plate 204 and the driven plate 206 viewed from the axial direction at the time of fastening. FIG. 3D is a schematic cross-sectional view showing the positional relationship between the drive plate 204 and the driven plate 206 at the time of fastening.

  As shown in FIGS. 3A and 3C, the drive plate 204 of the present embodiment has a plurality of divided plates 204D divided in the rotational direction of the propeller shaft 126 (hereinafter simply referred to as the rotational direction). . The division plate 204D has a substantially fan shape obtained by dividing a drive plate (not shown) formed in an annular shape (donut shape) into a plurality of pieces at equal intervals in a rotational direction (circumferential direction). In the present embodiment, although one drive plate 204 is divided into six in the division plate 204D, the number of divisions is not limited to this, and it may be divided into two or more (plural) sheets. Further, the division plate 204D may have a substantially fan shape in which a drive plate formed in an annular shape is divided at unequal intervals in the rotational direction. In the present embodiment, each of the plurality of driven plates 206 has an annular shape (a donut shape).

  In the present embodiment, all of the plurality of drive plates 204 are configured by divided plates 204D. However, the present invention is not limited to this, and at least one drive plate 204 of the plurality of drive plates 204 may be configured by the divided plate 204D.

  Further, as shown in FIGS. 3B and 3D, the cylindrical portion 202b of the clutch drum 202 of the present embodiment has an inner peripheral surface 202ba. The cylindrical portion 202b has a tapered portion (inclined portion) 202bb in which the inner diameter of the inner peripheral surface 202ba decreases in the approaching direction (pinion gear shaft 136 side) in which the transfer piston 210 approaches the plurality of drive plates 204.

  The inner circumferential surface 202ba and the tapered portion 202bb have straight grooves (not shown) extending in the axial direction. The rectilinear groove is engaged with a plurality of drive plates 204 (divided plates 204D), and guides the divided plates 204D in the axial direction. Further, the rectilinear groove engages with the dividing plate 204D to restrict the movement of the dividing plate 204D in the rotation direction. The plurality of drive plates 204 (dividing plates 204D) are provided in the tapered portion 202bb, and move in the axial direction on the tapered portion 202bb as the transfer piston 210 moves.

  As shown in FIG. 3B, the plurality of drive plates 204 (divided plates 204D) are separated from the plurality of driven plates 206 in the axial direction when the pressure from the transfer piston 210 is released when not fastened. Move in the direction. As a result, the plurality of drive plates 204 move to the propeller shaft 126 side of the tapered portion 202bb. The tapered portion 202bb has an inner diameter on the propeller shaft 126 side that is larger than an inner diameter on the pinion gear shaft 136 side. Also, when the propeller shaft 126 is rotating, the clutch drum 202 and the plurality of drive plates 204 rotate integrally with the propeller shaft 126. Therefore, centrifugal force is applied to the plurality of drive plates 204 (split plates 204D) radially outward. Thereby, division | segmentation plate 204D moves to radial direction outer side. The state of the divided plate 204D at this time is shown in FIG. As shown in FIG. 3A, the divided plates 204D are separated from each other in the rotational direction.

  Here, when the rotation of the propeller shaft 126 is stopped, the centrifugal force applied to the plurality of drive plates 204 (dividing plates 204D) disappears, and the dividing plates 204D move radially inward. FIG. 4 is a view showing an engaged state between the divided plate 204D and the rectilinear grooves SG formed in the tapered portion 202bb. FIG. 4A is a diagram showing a state of engagement with the rectilinear groove SG when the divided plate 204D moves radially outward. FIG. 4B is a diagram illustrating an engagement state with the straight groove SG when the divided plate 204D moves radially inward.

  As shown in FIGS. 4A and 4B, the dividing plate 204D has two protrusions 204Da and 204Db that engage with the rectilinear groove SG. Further, the rectilinear groove SG has two recesses SGa and SGb that engage with the two protrusions 204Da and 204Db of the divided plate 204D. Here, the engagement between one of the plurality of divided plates 204D and the straight groove SG will be described. However, the other divided plates 204D also have the same configuration as the configuration shown in FIGS. 4 (a) and 4 (b). That is, the other divided plate 204D is provided with two protrusions 204Da and 204Db, respectively. Further, the rectilinear grooves SG have a plurality of depressions SGa and SGb corresponding to the two protrusions 204Da and 204Db of the other divided plate 204D.

  The length (depth) in the radial direction of the plurality of depressions SGa and SGb is equal to or longer than the length in the radial direction of the two protrusions 204Da and 204Db. Further, the radial lengths of the two protrusions 204Da and 204Db are larger than the maximum moving distance that the dividing plate 204D can move in the radial direction. Therefore, when the dividing plate 204D is moved radially outward or radially inward, the engagement between the two protrusions 204Da and 204Db and the two depressions SGa and SGb is prevented from being released. Can do.

  Returning to FIG. 3, as shown in FIG. 3D, the plurality of drive plates 204 (division plates 204D) move toward the pinion gear shaft 136 of the tapered portion 202bb when they are pressed by the transfer piston 210 at the time of fastening. . The tapered portion 202bb has an inner diameter on the pinion gear shaft 136 side that is smaller than an inner diameter on the propeller shaft 126 side. Accordingly, when the divided plate 204D moves toward the pinion gear shaft 136 of the tapered portion 202bb, the divided plate 204D moves radially inward. The state of the divided plate 204D at this time is shown in FIG. 3 (c). As shown in FIG. 3C, the divided plates 204D are in contact with each other in the rotational direction.

  Thus, the plurality of drive plates 204 (split plates 204D) move radially inward at the time of fastening. When the dividing plate 204D moves inward in the radial direction, the dividing plate 204D is opposed to the plurality of driven plates 206 in the axial direction, as can be seen by comparing FIG. 3 (a) and FIG. 3 (c). (Facing area) increases. That is, the facing area where the plurality of drive plates 204 and the plurality of driven plates 206 face each other in the axial direction when not fastened is larger than the facing area where they face each other in the axial direction when fastened. Therefore, the contact areas where the plurality of drive plates 204 and the plurality of driven plates 206 contact each other at the time of fastening can be increased, and a predetermined torque transmission capacity at the time of fastening can be secured.

  On the other hand, the plurality of drive plates 204 (split plates 204D) move radially outward at the time of non-fastening. When the divided plate 204D moves outward in the radial direction, the divided plate 204D is opposed to the plurality of driven plates 206 in the axial direction, as can be seen by comparing FIG. 3 (a) and FIG. 3 (c). (Facing area) decreases. Therefore, the plurality of drive plates 204 and the plurality of driven plates 206 can reduce the opposing area facing each other when not engaged, and reduce the loss torque due to the drag resistance of the wet multi-plate clutch 200 when not engaged. Can do.

  When the split plate 204D moves radially outward when not fastened, the inner diameter side of the split plate 204D is opposed to the outer diameter side of the plurality of driven plates 206 in the axial direction (overlapping region). Is set to have. As described above, when the plurality of drive plates 204 (division plates 204D) have overlapping regions that overlap in the axial direction with the plurality of driven plates 206 at the time of non-fastening, fastening errors with the plurality of driven plates 206 at the time of fastening Does not occur.

  As described above, the wet-type multi-plate clutch 200 of the present embodiment has the transfer piston (drive unit) 210 and the taper portion (drive unit) 202bb in order to move the division plate 204D in the radial direction. As a result, the facing area in which the drive plate 204 and the driven plate 206 face in the axial direction during fastening (contact position) is larger than the facing area in which the drive plate 204 and the driven plate 206 face in the axial direction during non-fastening (separating position). Become. As a result, it is possible to reduce the loss torque at the time of non-engagement while securing a predetermined torque transmission capacity at the time of engagement.

  In the above embodiment, by providing the tapered portion 202bb in the cylindrical portion 202b of the clutch drum 202, the configuration has been described in which the plurality of drive plates 204 (division plates 204D) are moved in the radial direction. However, the present invention is not limited to this, and the drive unit may be configured to move the plurality of drive plates 204 (division plates 204D) in the radial direction by the hydraulic pressure of hydraulic fluid delivered from a hydraulic circuit (not shown). . For example, the hydraulic pressure supplied from the hydraulic circuit (not shown) to the hydraulic chamber 212 is branched, supplied to the drive unit of the plurality of drive plates 204 (divided plates 204D), and shared as the hydraulic pressure for moving the plurality of drive plates 204 in the radial direction It may be configured to In this case, since the hydraulic pressure is supplied from the hydraulic circuit (not shown) to the hydraulic chamber 212 when the plurality of couplings 134 are fastened, the coupling 134 is also fastened to the drive portions of the plurality of drive plates 204. The hydraulic pressure is supplied from a hydraulic circuit (not shown). By doing so, the plurality of drive plates 204 can be moved radially inward when the coupling 134 is fastened. With such a configuration, it is possible to move the plurality of drive plates 204 in the radial direction by the hydraulic pressure supplied to the hydraulic chamber 212 without separately adding a hydraulic pressure supply device for moving the plurality of drive plates 204 in the radial direction. it can. However, the present invention is not limited to this, and a hydraulic pressure supply device for moving the plurality of drive plates 204 may be separately provided independently of the hydraulic pressure supply device that supplies the hydraulic pressure to the hydraulic pressure chamber 212.

  In the above-described embodiment, an example in which the propeller shaft 126 is provided with the clutch drum 202 and the drive plate 204 and the pinion gear shaft 136 is provided with the driven plate 206 and the clutch hub 208 has been described. However, the present invention is not limited to this, and the propeller shaft (drive shaft) 126 is provided with the driven plate 206 and the clutch hub 208, and the pinion gear shaft (follower shaft) 136 is provided with the clutch drum 202 and the drive plate 204. Also good.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It is obvious that those skilled in the art can conceive of various changes or modifications within the scope of the claims, and it is naturally understood that they are also within the technical scope of the present invention. Is done.

  In the above embodiment, an example in which the plurality of drive plates (outer diameter side plates) 204 are configured by divided plates 204D divided in the rotational direction and configured to be movable in the radial direction has been described. However, the present invention is not limited to this, and a plurality of driven plates (inner diameter side plates) 206 may be constituted by divided plates that are divided in the rotational direction, and may be configured to be movable in the radial direction. Further, both of the plurality of drive plates 204 and the plurality of driven plates 206 may be configured by divided plates divided in the rotational direction and configured to be movable in the radial direction.

  In the above embodiment, an example in which the wet multi-plate clutch 200 is applied to the coupling 134 has been described. However, the present invention is not limited to this, and the wet multi-plate clutch 200 of the above-described embodiment can also be applied to a wet multi-plate clutch used in a device different from the coupling 134 such as a forward clutch and a start clutch.

  In the above-described embodiment, an example in which a plurality of drive plates 204 is provided at the end of the propeller shaft 126 and a plurality of driven plates 206 is provided at the end of the pinion gear shaft 136 is shown. However, the present invention is not limited to this, and a single drive plate 204 may be provided at the end of the propeller shaft 126 and a single driven plate 206 may be provided at the end of the pinion gear shaft 136. In this case, the single drive plate 204 is configured by a plurality of divided plates 204D as described in the above embodiment.

  The present invention is applicable to a power transmission device.

126 propeller shaft 136 pinion gear shaft 200 wet multi-plate clutch 204 drive plate 204 D split plate 206 driven plate 210 transfer piston

Claims (5)

A first plate provided on a first rotating shaft and disposed in a lubricating oil supply space to which lubricating oil is supplied;
A second plate provided on a second rotation shaft, including a plurality of divided plates axially opposed to the first plate and divided in the rotational direction, and disposed in the lubricating oil supply space;
The first plate and the second plate are driven in the axial direction between a contact position at which the first plate and the second plate are in contact and a separated position at which the first plate and the second plate are separated. And a drive unit
The dividing plate is configured to be movable in the radial direction of the second rotation shaft, and the contact position is more than the facing area in which the first plate and the second plate face in the axial direction at the separated position. The power transmission device, wherein a facing area in which the first plate and the second plate face in the axial direction is larger. The first rotating shaft includes a plurality of the first plates,
The second rotating shaft includes a plurality of the second plates,
The power transmission device according to claim 1, wherein the plurality of first plates and the plurality of second plates are alternately arranged in the axial direction. The power transmission device according to claim 1, wherein the drive unit includes a piston that presses the divided plate in the axial direction by moving in the axial direction. A cylindrical portion having an inner circumferential surface engaged with the divided plate;
The power transmission device according to claim 3, wherein the cylindrical portion includes an inclined portion in which an inner diameter of the inner circumferential surface decreases in a direction in which the drive portion presses the dividing plate. The power transmission device according to claim 3, wherein the drive unit moves the piston in the axial direction by hydraulic pressure, and moves the dividing plate in the radial direction by hydraulic pressure that moves the piston.

Images