JP2005299920A - Clutch device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clutch device to effect engagement of a clutch rapidly with excellent responsiveness. <P>SOLUTION: The clutch device 50 is provided with a clutch drum 51; and a piston 52 movably situated in the clutch drum 51, and working oil is fed to an oil chamber 53 between the clutch drum 51 and the piston 52, when the clutch is engaged, to move the piston 52. A cancel plate 54 to define a centrifugal oil pressure cancellation chamber 55 filled with the working oil is situated on the opposite side to the oil chamber 53 with the piston 52 positioned therebetween. When the clutch is engaged, the working oil in the centrifugal oil pressure cancellation chamber 55 is discharged from the outer peripheral side of the centrifugal oil pressure cancellation chamber 55 to the outside. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a clutch device including a clutch drum and a piston, and more particularly to a clutch device capable of canceling centrifugal hydraulic pressure generated in an oil chamber between the clutch drum and the piston.

  2. Description of the Related Art Conventionally, a clutch device having a centrifugal oil pressure cancellation chamber for canceling centrifugal oil pressure generated in an oil chamber between a clutch drum and a piston is known (see, for example, Patent Document 1). In this clutch device, a cancel plate is disposed on the opposite side of the oil chamber across the piston, and a centrifugal hydraulic pressure cancel chamber filled with hydraulic oil is defined between the cancel plate and the piston. When the clutch is engaged, hydraulic oil is supplied into the oil chamber so that the piston moves toward the cancel plate. In this case, since the volume of the centrifugal oil pressure cancellation chamber decreases as the piston approaches the cancel plate, the hydraulic oil in the centrifugal oil pressure cancellation chamber needs to be discharged to the outside. For this reason, in the clutch device described in Patent Document 1, when the clutch is engaged, the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber is removed from the notch formed in the inner peripheral portion of the cancellation plate and the rotating member to which the cancellation plate is fixed. Is discharged to the outside.

JP 2001-41261 A

  However, in the conventional clutch device configured as described above, the time lag from when the piston starts to move toward the cancel plate for clutch engagement until the clutch engagement is completed is large. When the ambient temperature at which the property deteriorates is low, such a time lag may become remarkable.

  Therefore, an object of the present invention is to provide a clutch device that can execute clutch engagement quickly and with high responsiveness.

  A clutch device according to the present invention includes a clutch drum and a piston movably disposed in the clutch drum, and supplies hydraulic oil to an oil chamber between the clutch drum and the piston when the clutch is engaged. In the clutch device for moving the piston, a cancel plate defining a centrifugal hydraulic pressure cancellation chamber filled with hydraulic oil is provided on the opposite side of the oil chamber across the piston, and the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber is engaged when the clutch is engaged. Is discharged to the outside from the outer peripheral side of the centrifugal hydraulic pressure canceling chamber.

  In general, the centrifugal oil pressure is generated in the centrifugal oil pressure cancellation chamber as well as the oil chamber between the clutch drum and the piston. Therefore, the hydraulic oil pressure in the centrifugal oil pressure cancellation chamber increases toward the outer peripheral side of the cancellation chamber. Become. Therefore, if the hydraulic oil in the centrifugal oil pressure cancellation chamber is discharged from the outer peripheral side of the cancellation chamber to the outside when the clutch is engaged as in this clutch device, the piston starts to move toward the cancellation plate. As a result, the amount of hydraulic oil corresponding to the amount of movement of the piston quickly flows out from the centrifugal hydraulic pressure cancel chamber to the outside. As a result, in this clutch device, even when the ambient temperature is low and the viscosity of the hydraulic fluid is high, the time lag from the start to the completion of clutch engagement can be reduced well, and the clutch engagement is prevented. It can be executed quickly and with good responsiveness.

  In this case, in the clutch device according to the present invention, it is preferable that when the piston is moved toward the cancel plate for clutch engagement, a flow path is formed between the outer peripheral portion of the piston and the outer peripheral portion of the cancel plate.

  In addition, the piston has a step portion that can come into contact with the outer peripheral portion of the cancel plate, and the step portion cooperates with the cancel plate when releasing the clutch to regulate the outflow of hydraulic oil from the centrifugal hydraulic pressure cancel chamber. It is preferable. According to such a configuration, when the clutch is released, it is possible to reliably prevent the hydraulic oil from flowing out from the centrifugal hydraulic pressure cancellation chamber. When the clutch is engaged, the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber is removed. Can be quickly discharged from the outer peripheral side to the outside. Such a configuration can be easily realized at low cost.

  Furthermore, a hole is formed in each of the outer periphery of the piston and the outer periphery of the cancel plate. When the piston is moved for clutch engagement, the piston hole and the cancel plate hole communicate with each other. Also good. Even with such a configuration, when the clutch is released, it is possible to reliably prevent the hydraulic oil from flowing out of the centrifugal hydraulic pressure cancellation chamber. When the clutch is engaged, the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber is removed from the cancellation chamber. It can quickly flow out from the outer peripheral side to the outside. Such a configuration can also be easily realized at low cost.

  In the clutch device according to the present invention, it is preferable that the discharge of the hydraulic oil from the centrifugal oil pressure cancellation chamber is restricted when the clutch engagement is completed. Under such a configuration, when the clutch engagement is completed (substantially completed), the working fluid can be left in the centrifugal hydraulic pressure cancellation chamber. Thereby, when releasing the clutch, a reaction force by the centrifugal oil pressure can be applied to the piston from the working fluid remaining in the centrifugal oil pressure canceling chamber, so that the clutch can be released quickly and satisfactorily with good responsiveness.

  In this case, when the piston is moved toward the cancel plate for clutch engagement, a flow path is formed between the outer periphery of the piston and the outer periphery of the cancel plate, and the piston is further moved toward the cancel plate. It is preferable that the flow path is closed before the clutch engagement is completed. The piston is formed on the inner side of the first step portion that can come into contact with the outer peripheral portion of the cancel plate and the second step portion that can come into contact with the outer peripheral portion of the cancel plate. Preferably, a gap is formed between the first step portion and the second step portion between the outer peripheral portion of the cancel plate and the piston.

  According to the present invention, it is possible to realize a clutch device that can execute clutch engagement quickly and with high responsiveness.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an enlarged sectional view showing a part of a vehicle transaxle including a clutch device according to the present invention. A transaxle 1 shown in the figure is disposed on the side of an engine (not shown) and is connected to a crankshaft of the engine. The transaxle 1 includes a transaxle housing 2 and a transaxle case 3. A torque converter 10 is disposed inside the transaxle housing 2, and a forward / reverse switching mechanism (power transmission device) 30 including a clutch device 50 according to the present invention and a belt-type continuously variable transmission are arranged inside the transaxle case. A machine (CVT) 5 and a final reduction gear (differential device) (not shown) are arranged.

  The torque converter 10 includes a front cover 11 that is fixed to an engine crankshaft via a drive plate (not shown). A pump impeller 12 is attached to the front cover 11 as shown in FIG. The torque converter 10 includes a turbine runner 13 that can rotate in a state of facing the pump impeller 12. The turbine runner 13 is fixed to an input shaft S that extends substantially coaxially with the crankshaft via a turbine hub 14. Further, a stator 15 is disposed inside the pump impeller 12 and the turbine runner 13. A hollow shaft 17 is fixed to the stator 15 via a one-way clutch 16 that sets the rotation direction to only one direction, and the above-described input shaft S is inserted into the hollow shaft 17. The torque converter 10 configured as described above operates as a torque amplifier when the rotational speed difference between the pump impeller 12 and the turbine runner 13 is large, and operates as a fluid coupling when the rotational speed difference between the two becomes small.

  The end of the input shaft S on the front cover 11 side includes a damper unit 18 coupled to the turbine hub 14, a lock-up piston 190 and a friction plate 191, and the front cover 11 and the damper unit 18 (the turbine hub 14 ) Is arranged. The lock-up clutch mechanism 19 is activated when the vehicle speed reaches a predetermined speed after the vehicle starts, so that the power transmitted from the engine to the front cover 11 is mechanically and directly transmitted to the input shaft S. Become. Further, the fluctuation of the torque transmitted from the front cover 11 to the input shaft S is absorbed by the damper unit 18.

  As shown in FIG. 1, in the lockup clutch mechanism 19 of this embodiment, the front end portion of the input shaft S on the front cover 11 side is reduced in diameter, and the lockup piston 190 is reduced by the reduced diameter portion Sd of the input shaft S. The inner peripheral side end 190a is supported. The inner peripheral end 190a of the lockup piston 190 extends toward the turbine hub 14 and is positioned by the end surface Se of the large diameter portion of the input shaft S. Thereby, in the lockup clutch mechanism 19, the differential pressure before and after the turbine hub 14 can be eliminated at the time of lockup, so that it is not necessary to arrange a thrust bearing between the front cover 11 and the lockup piston 190. Further, in this embodiment, as can be seen from FIG. 1, the pressure receiving area of the lockup piston is increased by the diameter of the input shaft S, so that the torque capacity can be increased by that amount. In the example of FIG. 1, the lock-up clutch mechanism 19 is configured as a single-plate clutch mechanism, but is not limited thereto, and the lock-up clutch mechanism 19 is configured as a multi-plate clutch mechanism. Also good.

  Further, as shown in FIG. 2, the front end portion of the input shaft S on the front cover 11 side may not be reduced in diameter. In the lockup clutch mechanism 19A of the torque converter 10A shown in FIG. 2, the inner peripheral side end portion 190a of the lockup piston 190 is supported by the tip portion of the input shaft S which is not reduced in diameter. The hub 14 is positioned by a recess 14a formed on the front cover 11 side. Even if such a configuration is adopted, it is possible to eliminate the differential pressure across the turbine hub 14 during lockup, so that it is not necessary to dispose a thrust bearing between the front cover 11 and the lockup piston 190.

  As shown in FIG. 1, an oil pump 20 is disposed between the torque converter 10 and the forward / reverse switching mechanism 30. The oil pump 20 includes a pump body 21, a pump cover 22, a drive gear 23, a driven gear 24, and the like. The drive gear 23 is connected to the pump impeller 12 via the hub 25 and is splined to the hollow shaft 17. Further, the pump body 21 and the pump cover 22 are fixed to the transaxle case 3 side by being bolted to each other. Accordingly, the engine power is transmitted to the drive gear 23 via the pump impeller 12, thereby driving the oil pump 20.

  On the other hand, the forward / reverse switching mechanism 30 is provided on a power transmission path between the input shaft S and the transmission 5, and includes a planetary gear mechanism 40 and a clutch device 50 according to the present invention used as a so-called forward clutch, And reverse brake 70. The planetary gear mechanism 40 holds the ring gear 41, a sun gear 42 attached to the input shaft S, a plurality of pinion gears 44 that mesh with the ring gear 41 or the sun gear 42, and the pinion gear 44 so as to be integrally revolved around the sun gear 42. Carrier 45. As the ring gear 41, the sun gear 42, and the pinion gear 44, helical gears are employed to reduce gear noise.

  The clutch device 50 connects / disconnects the power transmission path between the input shaft S and the primary shaft 6 of the transmission 5 via the planetary gear mechanism 40. As shown in FIGS. 1 and 3, the clutch device 50 includes a clutch drum 51 coupled to the input shaft S via the pump cover 22 and the like. The clutch drum 51 includes a base 51a fitted in the pump cover 22 in the axial direction of the input shaft S, a radial end 51b extending from the base 51a in the radial direction of the input shaft S, and a radial end 51b. And an outer cylindrical portion 51c extending substantially in parallel with the input shaft S from the outer peripheral portion toward the transmission 5.

  A piston 52 is slidably disposed inside the clutch drum 51. The piston 52 includes a base portion 52a fitted so as to be slidable in the axial direction of the input shaft S with respect to the base portion 51a of the clutch drum 51, and a radial end extending from the base portion 52a in the radial direction of the input shaft S. A portion 52b and an outer cylindrical portion (outer peripheral portion of the piston) 52c extending substantially parallel to the input shaft S from the outer peripheral portion of the radial end portion 52b toward the transmission 5. The space between the base portion 51a of the clutch drum 51 and the base portion 52a of the piston 52 and the space between the outer cylindrical portion 51c of the clutch drum 51 and the outer cylindrical portion 52c of the piston 52 are kept in an oil-tight state. An oil chamber 53 is defined between the clutch drum 51 and the piston 52, and a hole 51 d for supplying hydraulic oil to the oil chamber 53 is formed in the base 51 a of the clutch drum 51.

  Further, a cancel plate 54 is fixed to the base 51 a of the clutch drum 51 so as to be positioned on the opposite side of the oil chamber 53 with the piston 52 interposed therebetween. The outer peripheral end portion of the cancel plate 54 reaches the vicinity of the inner surface of the outer cylindrical portion 51 c of the clutch drum 51, and the cancel plate 54 cooperates with the back surface of the piston 52 to define a centrifugal hydraulic pressure cancel chamber 55. The base 51a of the clutch drum 51 is formed with a hole 51e for supplying hydraulic oil to the centrifugal hydraulic pressure cancellation chamber 55, and the centrifugal hydraulic pressure cancellation chamber 55 is basically filled with hydraulic oil. A return spring 56 is disposed between the back surface of the piston 52 (radial end 52b) and the cancel plate 54. The return spring 56 biases the piston 52 toward the radial end 51 b of the clutch drum 51.

  A plurality of splines 51s extending in parallel with the input shaft S are arranged at predetermined intervals on the inner surface of the outer cylindrical portion 51c of the clutch drum 51. The splines 51s are connected to the pressure receiving plate 57 and the spline 51s. A plurality of friction plates 58 are slidably fitted. The pressure receiving plate 57 and the friction plates 58 are slidable in the axial direction of the input shaft S with respect to the clutch drum 51, and are integrated with the clutch drum 51 in the circumferential direction of the input shaft S. The pressure receiving plate 57 is disposed closest to the piston 52 so as to be in contact with the free end portion of the outer cylindrical portion 52 c of the piston 52. Further, the friction plate 58 closest to the transmission 5 is positioned in the axial direction by a snap ring 59.

  As shown in FIG. 3, the carrier 45 that integrally holds the plurality of pinion gears 44 has a cylindrical portion 45 a that extends toward the clutch drum 51, and the outer peripheral surface of the cylindrical portion 45 a is also input. A plurality of splines 45s extending in parallel with the shaft S are arranged at a predetermined interval. A plurality of friction plates 46 are slidably fitted in these splines 45s. Each friction plate 46 is disposed between adjacent friction plates 58 of the clutch drum 51, and is slidable in the axial direction of the input shaft S with respect to the cylindrical portion 45a. It is integrated with the cylindrical portion 45a in the circumferential direction. The carrier 45 has a connecting portion 45 b extending toward the transmission 5, and the connecting portion 45 b is connected to the primer shaft 6 (spline fitting).

  The reverse brake 70 controls the rotation direction of the primary shaft 6 by allowing or restricting the rotation of the ring gear 41. That is, the reverse brake 70 has a plurality of splines 70s extending in parallel with the input shaft S. The plurality of splines 70s are arranged at predetermined intervals on the inner surface of the transaxle case 3 so as to surround the ring gear 41, and a plurality of friction plates 71 are slidably fitted into these splines 70s. ing. Each friction plate 71 is slidable in the axial direction of the input shaft S with respect to the transaxle case 3, and is integrated with the transaxle case 3 in the circumferential direction of the input shaft S. Further, the friction plate 71 closest to the clutch drum 51 is positioned in the axial direction by the snap ring 72.

  A plurality of splines 41 s extending in parallel with the input shaft S are also arranged on the outer peripheral surface of the ring gear 41 at a predetermined interval. A plurality of friction plates 73 are slidably fitted in these splines 41s. Each friction plate 73 is disposed between the friction plates 71 on the transaxle case 3 side, and is slidable in the axial direction of the input shaft S with respect to the ring gear 41, while in the circumferential direction of the input shaft S. It is integrated with the ring gear 41.

  Further, a brake piston 74 is slidably disposed inside the transaxle case 3, and an oil chamber 75 is formed behind the brake piston 74 (see FIG. 1). A retainer 77 is connected to the brake piston 74 via a return spring 76. The retainer 77 is fitted in each spline 70 s of the transaxle case 3 and can contact the friction plate 71 closest to the transmission 5. The brake piston 74, the oil chamber 75, the return spring 76 and the retainer 77 constitute a hydraulic actuator for the reverse brake 70.

  Now, in the transaxle 1 configured as described above, when the transmission 5 is set from the parking or neutral range to the drive range by the user, the oil between the clutch drum 51 and the piston 52 via the hole 51d. Hydraulic fluid is supplied to the chamber 53, the piston 52 moves toward the cancel plate 54 (transmission 5) against the urging force of the return spring 56, and the free end portion of the outer cylindrical portion 52c of the piston 52 receives pressure. The plate 57 is pressed. As a result, the friction plate 58 on the clutch drum 51 side and the friction plate 46 on the carrier 45 (cylindrical portion 45 a) side are in frictional contact (clutch engagement), and the carrier 45 coupled to the clutch drum 51 and the primary shaft 6. Will be linked. As a result, when clutch engagement is executed by the clutch device 50, the driving force from the engine is transmitted to the transmission 5 (primary shaft 6) via the carrier 45 in the same rotational direction.

  The hydraulic oil is discharged from the oil chamber 53, and the reverse is made in a state where the friction contact between the friction plate 58 on the clutch drum 51 side and the friction plate 46 on the carrier 45 (cylindrical portion 45a) side is released (clutch release). When the ring gear 41 is locked by the brake 70, the driving force from the engine is transmitted to the transmission 5 via the carrier 45 in the reverse rotation.

  Here, in the clutch device 50, since the clutch drum 51 rotates together with the input shaft S, centrifugal force acts on the hydraulic oil in the oil chamber 53, and centrifugal hydraulic pressure is generated in the oil chamber 53. For this reason, in the clutch device 50, a centrifugal hydraulic pressure cancel chamber 55 filled with hydraulic oil is defined behind the piston 52, and the centrifugal force generated in the oil chamber 53 by the centrifugal hydraulic pressure generated in the centrifugal hydraulic pressure cancel chamber 55 is defined. Hydraulic pressure is offset. In the clutch device 50 configured as described above, it is necessary to move the piston 52 toward the cancel plate 54 in order to engage the clutch. When the piston 52 approaches the cancel plate 54, Volume decreases. Therefore, when the clutch is engaged, it is necessary to discharge the hydraulic oil in the centrifugal hydraulic pressure cancel chamber 55 to the outside. However, if the hydraulic oil is not smoothly discharged from the centrifugal hydraulic pressure cancel chamber 55, the piston 52 is The time lag from the start of moving toward the cancel plate 54 to the completion of clutch engagement will increase.

  Considering such points, in the clutch device 50 according to the present invention, the hydraulic oil in the centrifugal hydraulic pressure cancel chamber 55 is discharged to the outside from the outer peripheral side of the cancel chamber 55 when the clutch is engaged. That is, during the rotation of the input shaft S, the centrifugal oil pressure is generated in the centrifugal oil pressure canceling chamber 55 in the same manner as the oil chamber 53 between the clutch drum 51 and the piston 52. The oil pressure increases toward the outer peripheral side in the cancel chamber 55. Therefore, if the hydraulic oil in the centrifugal hydraulic pressure cancel chamber 55 is discharged from the outer peripheral side of the cancel chamber 55 to the outside when the clutch is engaged, when the piston 52 starts to move toward the cancel plate 54, The amount of hydraulic oil corresponding to the amount of movement of the piston 52 quickly flows out from the centrifugal hydraulic pressure cancel chamber 55 to the outside.

  In the present embodiment, in order to achieve quick discharge of the hydraulic oil from the cancel chamber 55 when the clutch is engaged and prevention of the hydraulic oil from flowing out of the cancel chamber 55 when the clutch is released, it is easy to achieve at low cost. 3 and the configuration shown in FIG. 4 are employed. That is, a stepped portion 52 d that protrudes toward the input shaft S is formed over the entire circumference at the free end portion of the outer cylindrical portion 52 c of the piston 52, and the sealing material 60 is provided at the outer peripheral end portion of the cancel plate 54. Is fixed all around. The innermost peripheral portion of the stepped portion 52d is closer to the input shaft S than the outermost peripheral portion of the seal material 60 of the cancel plate 54, and the cancel plate 54 has the seal material 60 (the outer peripheral end portion of the cancel plate 54) as a piston. 52 is fixed to the clutch drum 51 so as to be positioned on the radial end 52b side of the end surface of the outer cylindrical portion 52c.

  Thereby, in a state where the pressure of the pressure receiving plate 57 by the piston 52 is released (clutch release state), the stepped portion 52d of the piston 52 and the sealing material 60 of the cancel plate 54 (the outer peripheral end portion of the cancel plate 54) are illustrated. 3 abut against each other. Therefore, the step 52d of the piston 52 cooperates with the cancel plate 54 (seal member 60) when releasing the clutch to reliably prevent the hydraulic oil from flowing out of the centrifugal hydraulic pressure cancel chamber 55.

  On the other hand, when the piston 52 is moved toward the cancel plate 54 for clutch engagement, as shown in FIG. 4, the gap between the step 52 d of the piston 52 and the sealing material 60 of the cancel plate 54 is obtained. A flow path (gap) is formed. Therefore, in the clutch device 50, when the clutch is engaged, the hydraulic oil in the centrifugal oil pressure cancel chamber 55 can be quickly discharged from the outer peripheral side of the cancel chamber 55 to the outside. As a result, in the clutch device 50, even when the ambient temperature is low and the viscosity of the hydraulic oil is high, the time lag from the start to the completion of the clutch engagement can be reduced well, and the clutch engagement is quickly responded. It can be performed well. The hydraulic fluid that has flowed outside from the outer peripheral side of the centrifugal hydraulic pressure cancellation chamber 55 is returned to the hydraulic system through a hole 51f formed in the base 51a of the clutch drum 51.

  FIG. 5 is a sectional view showing a modification of the clutch device according to the present invention. In the example of FIG. 5, instead of forming a step portion on the outer cylindrical portion 52c of the piston 52, a stepped sealing material 61 having a step portion 61d at the free end portion of the outer cylindrical portion 52c is fixed over the entire circumference. Yes. Further, no sealing material is attached to the outer peripheral end of the cancel plate 54. Under such a configuration, in the clutch released state, the stepped portion 61d of the stepped seal material 61 attached to the piston 52 and the outer peripheral end of the cancel plate 54 abut against each other as shown in FIG. Accordingly, the step portion 61d on the piston 52 side prevents the hydraulic oil from flowing out of the centrifugal hydraulic pressure cancel chamber 55 in cooperation with the cancel plate 54 when releasing the clutch.

  On the other hand, when the piston 52 is moved toward the cancel plate 54 for clutch engagement, there is no flow between the step portion 61 d of the stepped seal material 61 attached to the piston 52 and the outer peripheral end portion of the cancel plate 54. A path (gap) is formed, and the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber 55 quickly flows out from the outer peripheral side of the cancellation chamber 55 to the outside. Thus, even if the configuration of FIG. 5 is adopted, it is possible to reduce the cost of quickly discharging the hydraulic oil from the cancel chamber 55 when the clutch is engaged and preventing the hydraulic oil from flowing out of the cancel chamber 55 when the clutch is released. And can be easily achieved.

  6 and 7 are sectional views showing other modified examples of the clutch device according to the present invention. In the example of FIGS. 6 and 7, a hole 52 h is formed in the outer cylindrical portion 52 c of the piston 52 instead of providing a step portion for the piston 52. The cancel plate 54 has an outer cylindrical portion 54c that extends substantially parallel to the input shaft S toward the base portion 51a of the clutch drum 51, and the outer cylindrical portion 54c has a hole 54h. Is formed.

  As shown in FIG. 6, the hole 52 h of the piston 52 and the hole 54 h of the cancel plate 54 do not overlap in the clutch release state where the piston 52 is located on the rightmost side in the drawing. A sealant is provided between the outer cylindrical portion 52c of the piston 52 and the outer cylindrical portion 54c of the cancel plate 54 so as to be positioned between the hole portion 52h and the hole portion 54h when the clutch is released. 62 is interposed over the entire circumference. Further, sealing materials 63 and 64 are also provided at both ends of the outer cylindrical portion 54c of the cancel plate 54. By these sealing materials 62, 63 and 64, in the clutch released state, the outflow of hydraulic oil from the centrifugal hydraulic pressure cancel chamber 55 is reliably prevented.

  On the other hand, when the piston 52 is moved toward the cancel plate 54 for clutch engagement, as shown in FIG. 7, the hole 52h formed in the outer cylindrical portion 52c of the piston 52 and the cancel The holes 54h formed in the outer cylindrical portion 54c of the plate 54 communicate with each other. As a result, a flow path including the holes 52h and 54h is formed between the outer peripheral portion of the piston 52 and the outer peripheral portion of the cancel plate 54, so that the hydraulic oil in the centrifugal hydraulic pressure cancel chamber 55 is removed from the cancel chamber. It is possible to quickly flow out from the outer peripheral side of 55 to the outside. Thus, even if the configuration shown in FIGS. 6 and 7 is adopted, the hydraulic oil is quickly discharged from the cancel chamber 55 when the clutch is engaged, and the hydraulic oil flows out from the cancel chamber 55 when the clutch is released. Prevention can be easily achieved at low cost.

  Hereinafter, a second embodiment of the clutch device according to the present invention will be described with reference to FIGS. Note that the same reference numerals are given to the same elements as those described in relation to the above-described embodiment, and redundant descriptions are omitted.

  Also in the clutch device 50 </ b> A shown in FIG. 8, a step portion 52 d that protrudes toward the input shaft S is formed on the free end portion of the outer cylindrical portion 52 c of the piston 52, and the outer periphery of the cancel plate 54 is The sealing material 60 is fixed to the end part over the entire circumference. The innermost peripheral portion of the stepped portion 52d is closer to the input shaft S than the outermost peripheral portion of the seal material 60 of the cancel plate 54, and the cancel plate 54 has the seal material 60 (the outer peripheral end portion of the cancel plate 54) as a piston. 52 is fixed to the clutch drum 51 so as to be positioned on the radial end 52b side of the end surface of the outer cylindrical portion 52c. And in this clutch apparatus 50A, the 2nd step part 52e is formed in the outer cylindrical part 52c of the piston 52 over the perimeter so that it may be located in the axial direction inner side of the step part 52d. The innermost peripheral portion of the second stepped portion 52e is slightly closer to the input shaft S than the outermost peripheral portion of the sealing material 60 of the cancel plate 54. An interval x (see FIG. 9) between the stepped portion 52d and the second stepped portion 52e is set to be longer than the axial length of the outer peripheral end portion of the cancel plate 54 to which the sealing material 60 is attached.

  In the clutch device 50A configured as described above, when the piston 52 is moved toward the cancel plate 54 for clutch engagement, as shown in FIG. 9, a step 52d (right end in the drawing) of the piston 52 A flow path (gap) is formed between the seal member 60 of the cancel plate 54 and between the step 52e (left end in the figure) of the piston 52 and the seal member 60 of the cancel plate 54. That is, a gap is formed between the outer peripheral portion of the cancel plate 54 and the piston 52 between the step portion 52d and the step portion 52e. Therefore, also in the clutch device 50A, the hydraulic oil in the centrifugal oil pressure cancel chamber 55 can be quickly discharged from the outer peripheral side of the cancel chamber 55 to the outside when the clutch is engaged.

  Then, when the piston 52 further approaches the cancel plate 54 from the state of FIG. 9 and the clutch engagement is almost completed, as shown in FIG. 10, the second step portion 52e of the piston 52 and the cancel plate 54 is brought into contact with the seal member 60, and the flow path between the step 52e (left end in the figure) of the piston 52 and the seal member 60 of the cancel plate 54 is closed before the clutch engagement is completed. . Thereby, in the clutch device 50, when the clutch engagement is completed (substantially completed), the working fluid can be left in the centrifugal hydraulic pressure cancellation chamber 55.

  As a result, in the clutch device 50A, even when the ambient temperature is low and the viscosity of the hydraulic oil is high, the time lag from the start to completion of the clutch engagement can be satisfactorily reduced, and the clutch engagement is quickly responded. It can be performed well. Further, in the clutch device 50A, when the transmission 5 is set from the drive range to the neutral or parking range and the clutch is released, the hydraulic oil remaining in the centrifugal hydraulic pressure cancellation chamber 55 is subjected to the centrifugal hydraulic pressure with respect to the piston 52. Since the reaction force can be applied, the clutch can be released quickly and with good responsiveness.

  As shown in FIG. 11, instead of forming the step portions 52d and 52e in the outer cylindrical portion 52c of the piston 52, a step portion 61d and the step portion 61d are formed on the inner peripheral surface of the outer cylindrical portion 52c. A stepped sealing material 61A having a second step portion 61e formed at a predetermined interval from the second step portion 61e may be fixed over the entire circumference. Thereby, it becomes possible to improve the durability of the piston 52 and the stepped portions 61d and 61e. Further, since the two step portions 61d and 61e can be formed only by fixing the stepped seal material 61A to the piston 52, the productivity can be improved. Further, in this case, since the seal material at the outer peripheral end of the cancel plate 54 can be omitted, the cost required for the cancel plate 54 can be reduced accordingly. In addition, instead of the stepped sealing material 61A having the stepped portion 61d and the second stepped portion 61e, the two sealing materials are formed in an outer cylindrical shape so that the first and second stepped portions are formed in the piston 52. You may fix to the internal peripheral surface of the part 52c.

  In the configuration of FIG. 11, when the piston 52 is moved toward the cancel plate 54 for clutch engagement, the step portion 61 d of the stepped seal material 61 fixed to the piston 52 and the outer peripheral portion of the cancel plate 54. A flow path (gap) is formed between the step portion 61 e of the stepped seal material 61 and the outer peripheral portion of the cancel plate 54. When the piston 52 further approaches the cancel plate and the clutch engagement is almost completed, the step portion 61e of the stepped seal material 61 comes into contact with the cancel plate 54, and the clutch engagement is completed. Before, the flow path between the step part 61e of the stepped sealing material 61 and the cancel plate 54 is closed.

  Accordingly, even when the configuration of FIG. 11 is adopted, the hydraulic oil in the centrifugal oil pressure cancel chamber 55 can be quickly discharged from the outer peripheral side of the cancel chamber 55 to the outside when the clutch is engaged. Therefore, even when the ambient temperature is low and the viscosity of the hydraulic oil is high, the time lag from the start to the completion of clutch engagement can be satisfactorily reduced, and the clutch engagement can be executed quickly and with good responsiveness. it can. Also in the configuration of FIG. 11, since the working fluid can remain in the centrifugal hydraulic pressure cancellation chamber 55 when the clutch engagement is completed, the centrifugal hydraulic pressure cancellation chamber 55 is released when the clutch engagement is released. A reaction force by centrifugal hydraulic pressure can be applied to the piston 52 from the hydraulic oil remaining inside. Therefore, even if the configuration of FIG. 11 is adopted, the clutch can be released quickly and with good responsiveness.

It is sectional drawing which shows a part of transaxle for vehicles containing the clutch apparatus by this invention. It is sectional drawing which shows the other torque converter applicable to the transaxle of FIG. It is sectional drawing which shows the clutch apparatus by this invention. It is sectional drawing which shows the clutch apparatus by this invention. It is sectional drawing which shows the modification of the clutch apparatus by this invention. It is sectional drawing which shows the other modification of the clutch apparatus by this invention. It is sectional drawing which shows the other modification of the clutch apparatus by this invention. It is sectional drawing which shows 2nd Embodiment of the clutch apparatus by this invention. It is an expanded sectional view for demonstrating operation | movement of the clutch apparatus of FIG. It is an expanded sectional view for demonstrating operation | movement of the clutch apparatus of FIG. It is sectional drawing which shows the modification in 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transaxle 5 Belt type continuously variable transmission 10, 10A Torque converter 19, 19A Lockup clutch mechanism 190 Lockup piston 190a Inner peripheral side end 20 Oil pump 30 Forward / reverse switching mechanism 40 Planetary gear mechanism 50 Clutch device 51 Clutch drum 51a Base 51b Radial end 51c Outer cylindrical part 51s Spline 52 Piston 52a Base 52b Radial end 52c Outer cylindrical part 52d, 52e Step part 52h Hole 53 Oil chamber 54 Cancel plate 54c Outer cylindrical part 54h Hole 55 Centrifugal hydraulic cancel chamber 60, 62, 63, 64 Sealing material 61, 61A Stepped sealing material 61d, 61e Stepped part 70 Reverse brake S Input shaft

Claims (7)

A clutch drum and a piston movably disposed in the clutch drum are provided, and hydraulic oil is supplied to an oil chamber between the clutch drum and the piston to move the piston when the clutch is engaged. In the clutch device,
A cancel plate defining a centrifugal hydraulic pressure cancellation chamber filled with hydraulic oil is provided on the opposite side of the oil chamber across the piston, and when the clutch is engaged, the hydraulic oil in the centrifugal hydraulic pressure cancellation chamber is A clutch device that is discharged to the outside from an outer peripheral side of a hydraulic pressure canceling chamber.   2. The flow path is formed between an outer peripheral portion of the piston and an outer peripheral portion of the cancel plate when the piston is moved toward the cancel plate to engage the clutch. The clutch device according to 1.   The piston has a stepped portion that can come into contact with the outer peripheral portion of the cancel plate, and the stepped portion cooperates with the cancel plate when the clutch is released, and hydraulic oil flows out of the centrifugal hydraulic pressure cancel chamber. The clutch device according to claim 1, wherein the clutch device is regulated.   A hole is formed in each of the outer periphery of the piston and the outer periphery of the cancel plate. When the piston is moved for engaging the clutch, the hole of the piston and the cancel plate The clutch device according to claim 1 or 2, wherein the hole portion communicates with each other.   5. The clutch device according to claim 1, wherein when the engagement of the clutch is completed, the discharge of the hydraulic oil from the centrifugal hydraulic pressure cancellation chamber is restricted.   When the piston is moved toward the cancel plate to engage the clutch, a flow path is formed between the outer peripheral portion of the piston and the outer peripheral portion of the cancel plate, and the piston faces the cancel plate. The clutch device according to claim 5, wherein when further moved, the flow path is closed before the clutch engagement is completed. The piston is formed on the inner side of the first step portion that can come into contact with the outer peripheral portion of the cancel plate and the second step portion that can come into contact with the outer peripheral portion of the cancel plate. A gap is formed between the first step portion and the second step portion between the outer peripheral portion of the cancel plate and the piston. 6. The clutch device according to 6.

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