JP2007113684A - Stationary cylinder type clutch device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stationary cylinder type clutch device capable of preventing partial wear of a clutch plate by transmitting the thrust of a piston to the clutch plate without energy loss, causing neither an increase in axial dimension nor an increase in weight. <P>SOLUTION: The stationary cylinder type clutch device comprises the clutch plate 51a arranged between a hub 41a and a drum 46a; the piston 51b provided at a stationary member 8 and receiving oil pressure to engage the clutch plate 51a; and a thrust bearing 52 arranged between the piston and the clutch plate. A roller 52a of the thrust bearing 52 is held to a race 52b, and the race 52b is fitted in an axially movable manner to the inner peripheral part of the drum 46a. A support plate 53 is arranged at a side face, facing the clutch plate, of the piston 51b, and an axial clearance δ smaller than a fitting allowance between the race 52b and the drum 46a is formed between the roller 52a and the support plate 53 when a clutch device is released. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a stationary cylinder type clutch device used for an automatic transmission, a continuously variable transmission, and the like.

In general, a clutch device includes a hub and a drum that constitute an input / output rotating member, a clutch plate disposed between an outer periphery of the hub and an inner periphery of the drum, an inner portion of the drum, and receives hydraulic pressure. It is comprised with the piston which fastens a clutch board. Since the clutch drum that forms the hydraulic chamber with the piston rotates integrally with the input rotary member or the output rotary member, it is necessary to provide a seal ring to prevent oil leakage in the oil supply path to the clutch drum, and the friction loss There is a problem that is large. In addition, since the centrifugal oil pressure is generated in the hydraulic chamber of the clutch drum by the centrifugal force accompanying the rotation, there is a problem that the hydraulic control becomes complicated.

In order to solve such a problem, Patent Document 1 discloses a stationary cylinder type clutch device. In this clutch device, a piston that receives hydraulic pressure and fastens a clutch plate is provided on a stationary member such as a transmission case. Therefore, it is not necessary to provide a seal ring for preventing oil leakage in the oil supply path to the clutch drum, friction loss can be reduced, and centrifugal oil pressure can be prevented from being generated in the hydraulic chamber of the clutch drum.

FIG. 7 shows the stationary cylinder type clutch device shown in FIG.
This clutch device presses a piston 101 housed in a case 100, a clutch plate (clutch disc and clutch plate) 104 disposed between a rotating clutch drum 102 and a clutch hub 103, and the clutch plate 104. A pressing member 105 and a thrust bearing 106 disposed between the piston 101 and the pressing member 105 are provided, and the thrust of the piston 101 is transmitted to the clutch plate 104 with a differential rotation. A return spring 107 is interposed between the case 100 and the piston 101. In a state where the clutch device is released, a predetermined clearance δ is provided between the pressing member 105 and the clutch plate 104. The portion where the piston 101 pushes the pressing member 105 via the thrust bearing 106 and the portion where the pressing member 105 pushes the clutch plate 104 are offset by a dimension R in the radial direction.

However, in this clutch device, since the race of the thrust bearing 106 and the piston 101 and the pressing member 105 are supported only by inlay fitting, the thrust bearing 106 and the piston 101 or between the thrust bearing 106 and the pressing member when the clutch is released. There is a possibility that a gap may be generated between 105. If the spigot part does not slide in the state where a gap is generated, a clearance is continuously generated during this time, and conversely, the clearance δ between the clutch plate 104 and the pressing member 105 cannot be obtained, and a complete clutch release state is obtained. It may not be possible.

In order to solve such a problem, Patent Document 2 proposes a stationary cylinder type clutch device having a structure as shown in FIG.
This clutch device presses the clutch plate 114, the piston 111 housed in the case 110, the clutch plate (clutch disc and clutch plate) 114 disposed between the rotating clutch drum 112 and the clutch hub 113. A pressing member 115 and a thrust bearing 116 disposed between the piston 111 and the pressing member 115 are provided, and the thrust of the piston 111 is transmitted to the clutch plate 114 with a differential rotation. A return spring 117 is interposed between the clutch hub 113 and the pressing member 115, and a spring force in the return direction is applied from the pressing member 115 to the piston 111 via the thrust bearing 116. In a state where the clutch device is released, a predetermined clearance δ is provided between the pressing member 115 and the clutch plate 114. Also in this clutch device, a portion where the piston 111 pushes the pressing member 115 via the thrust bearing 116 and a portion where the pressing member 115 pushes the clutch plate 114 are offset by a dimension R in the radial direction.

In the case of the clutch device shown in FIG. 8, the clearance δ between the clutch plate 114 and the pressing member 115 can be ensured, but the piston 111 moves the pressing member 115 through the thrust bearing 116 as in FIG. 7. Since the portion to be pressed and the portion to which the pressing member 115 presses the clutch plate 114 are offset in the radial direction, the thrust of the piston 111 is not effectively transmitted to the clutch plate 114 when the clutch device is engaged, resulting in energy loss. There is a possibility that the pressing member 115 is biased against the clutch plate 114 and the clutch plate 114 may be unevenly worn. Similarly, since the uneven contact also occurs between the thrust bearing 116 and the pressing member 115, there is a possibility that the durability of the thrust bearing 116 may be lowered. In order to prevent the uneven contact of the clutch plate 114 and the thrust bearing 116, there is a method of increasing the rigidity by increasing the plate thickness of the pressing member 115, but there is a drawback in that the axial dimension increases and the weight increases.
JP 10-61733 A JP-A-10-122260

Accordingly, an object of the present invention is to provide a stationary cylinder type clutch device that can transmit the thrust of the piston to the clutch plate without energy loss without causing an increase in axial dimension or weight, and prevent uneven wear of the clutch plate. There is.

In order to achieve the above object, the invention according to claim 1 is directed to a hub and a drum constituting an input / output rotating member, a clutch plate disposed between the outer periphery of the hub and the inner periphery of the drum, and a stationary member. The piston is disposed between the piston and the clutch plate and receives a hydraulic pressure, and is disposed between the piston and the clutch plate to allow thrust while allowing relative rotation between the piston and the clutch plate. In the stationary cylinder type clutch device having a thrust bearing for transmitting, the thrust bearing has at least one race and a rolling element rotatably held by the race, and the race is pivoted on an inner peripheral portion of the drum. It is fitted in a freely movable direction, and when the clutch device is released, the race and the piston are interposed between the thrust bearing and the piston. Providing stationary cylinder type clutch device, characterized in that Hamagodai smaller axial clearance between the serial drum is formed.

The rolling element of the thrust bearing is rotatably held by at least one race, and this race is fitted to the inner peripheral portion of the drum supporting the clutch plate so as to be movable in the axial direction. When the piston is operated, the piston can contact the thrust bearing supported by the drum to press the clutch plate, thereby fastening the clutch plate. Since the rolling elements and the race constituting the thrust bearing are fitted to the inner peripheral portion of the drum in the same manner as the clutch plate, the rolling element and the race can be configured in a small size and are held in the radial direction by the drum. Simple.
In the present invention, the thrust of the piston is directly transmitted to the clutch plate via the thrust bearing. Since no intermediate member such as a pressing member is interposed, the number of components can be reduced, the axial dimension can be reduced, and the weight can be reduced.
In addition, since the contact point between the piston and the thrust bearing and the contact point between the thrust bearing and the clutch plate can be aligned in the axial direction, the thrust of the piston is transmitted to the clutch plate without loss, and the thrust bearing is connected to the clutch plate. Therefore, uneven wear of the clutch plate can be prevented.
When the clutch device is released, an axial clearance smaller than the fitting allowance between the race and the drum is formed between the thrust bearing and the piston, so that a complete clutch release state can be obtained and the thrust bearing It can be prevented from falling off the drum. At the same time, the thrust bearing can serve to prevent the clutch plate from coming off.

A cylindrical guide portion that is bent toward the piston direction and slidably contacts the inner peripheral surface of the inner spline of the drum may be formed on the outer peripheral portion of the race that holds the rolling elements.
In this case, since the guide portion of the race can smoothly move in the axial direction along the inner peripheral surface of the drum, the tilt of the thrust bearing can be prevented and the clutch plate can be prevented from being caught. Therefore, the clutch plate can be stably engaged and released.

A claw piece that fits to the inner spline of the drum and prevents the race from rotating with respect to the drum may be formed on the outer periphery of the race that holds the rolling elements.
When the race on the clutch plate side rotates relative to the drum, wear and heat generation may occur between the clutch plate and the clutch plate. Therefore, by forming claw pieces that fit into the inner splines of the drum on the outer periphery of the race, the race can be reliably prevented from rotating.

As described above, according to the present invention, the race that holds the rolling element of the thrust bearing is slidably fitted to the inner periphery of the drum, and the race, the drum, and the drum are placed between the thrust bearing and the piston when the clutch is released. Since the axial clearance smaller than the fitting allowance is formed, a predetermined clearance can be stably secured between the thrust bearing and the piston when the clutch is released, and the thrust bearing falls off the drum. Can be prevented.
In addition, the thrust of the piston can be directly transmitted to the clutch plate via the thrust bearing (rolling element), and the contact point between the piston and the thrust bearing and the contact point between the thrust bearing and the clutch plate can be aligned in the axial direction. Therefore, energy loss can be reduced, and the thrust bearing does not strike the clutch plate, preventing uneven wear of the clutch plate.
Furthermore, since an intermediate member for transmitting the thrust of the piston to the clutch plate is not required, the number of parts can be reduced, the axial dimension can be reduced, and the weight can be reduced.

Embodiments of the present invention will be described below with reference to examples.

1 to 4 show an example of a continuously variable transmission to which a stationary cylinder type clutch device according to the present invention is applied.
The continuously variable transmission of this embodiment is an FF horizontal type automotive transmission, which is roughly switched between forward and reverse rotation of the input shaft 3 driven by the engine output shaft 1 via the torque converter 2 and the input shaft 3. The forward / reverse switching device 4 that transmits to the drive shaft 10, the continuously variable transmission A comprising the drive pulley 11, the driven pulley 21, and the V belt 15 wound between both pulleys, the power of the driven shaft 20 is output shaft 32. And a differential device 30 that transmits to the terminal. The input shaft 3 and the drive shaft 10 are arranged on the same axis, and the driven shaft 20 and the output shaft 32 of the differential device 30 are arranged parallel to the input shaft 3 and non-coaxially. Therefore, this continuously variable transmission has a three-axis configuration as a whole.
The V-belt 15 used in this embodiment is a known metal belt composed of a pair of endless tension bands and a large number of blocks supported by these tension bands.

Each component constituting the continuously variable transmission is accommodated in a transmission case 5. An oil pump 6 is disposed between the torque converter 2 and the forward / reverse switching device 4. As shown in FIG. 2, the oil pump 6 includes a pump body 7 fixed to the transmission case 5, a pump cover 8 fixed to the pump body 7, and between the pump body 7 and the pump cover 8. And a pump gear 9 housed in the housing. The pump gear 9 is driven by the pump impeller 2 a of the torque converter 2. The turbine runner 2b of the torque converter 2 is connected to the input shaft 3, and the stator 2c is supported by the pump cover 8 via the one-way clutch 2d.

As shown in FIG. 2, the forward / reverse switching device 4 includes a planetary gear mechanism 40, a reverse brake 50, and a direct coupling clutch 51. The sun gear 41 of the planetary gear mechanism 40 is connected to the input shaft 3, and the ring gear 42 is connected to the drive shaft 10 of the continuously variable transmission A. The planetary gear mechanism 40 is a single pinion system, the reverse brake 50 is provided between the carrier 44 supporting the pinion gear 43 and the transmission case 5, and the direct clutch 51 is provided between the carrier 44 and the sun gear 41. . When the direct clutch 51 is released and the reverse brake 50 is engaged, the rotation of the input shaft 3 is reversed and decelerated and transmitted to the drive shaft 10 to enter the forward travel state. On the contrary, when the reverse brake 50 is released and the direct clutch 51 is engaged, the carrier 44 and the sun gear 41 of the planetary gear mechanism 40 rotate together, so that the input shaft 3 and the drive shaft 10 are directly connected to each other, and the reverse running state It becomes.
The detailed structure of the forward / reverse switching device 4 will be described later.

The drive pulley 11 of the continuously variable transmission A is a fixed sheave 11a formed integrally on a drive shaft (pulley shaft) 10 and a movable supported on the drive shaft 10 so as to be axially movable and integrally rotatable. A sheave 11b and a hydraulic servo 12 provided behind the movable sheave 11b are provided. Shift control is performed by controlling the hydraulic pressure supplied to the hydraulic servo 12. The driven pulley 21 includes a fixed sheave 21a formed integrally on a driven shaft (pulley shaft) 20, a movable sheave 21b supported on the driven shaft 20 so as to be axially movable and integrally rotatable, and a movable sheave. And a hydraulic servo 22 provided behind 21b. By controlling the hydraulic pressure supplied to the hydraulic servo 22, the belt thrust required for torque transmission is given.

One end portion of the driven shaft 20 extends toward the engine side, and the output gear 27 is fixed to this one end portion. The output gear 27 meshes with the ring gear 31 of the differential device 30, and power is transmitted from the differential device 30 to the output shaft 32 extending left and right to drive the wheels.

Here, the forward / reverse switching device 4 will be described in detail with reference to FIGS.
The carrier 44 includes a disk-shaped carrier flange 45 and an annular carrier rim 46. The inner diameter portion of the carrier flange 45 extends in the front-rear direction and is supported on the input shaft 3 so as to be rotatable. The carrier flange 45 is integrally formed with a plurality of connecting portions 45a (see FIG. 2) protruding in the axial direction toward the carrier rim 46, and the pinion gear 43 is disposed in a circumferential space between the connecting portions 45a. . The distal end portion of the connecting portion 45a and the carrier rim 46 are metal-bonded by sintering, and the carrier flange 45 and the carrier rim 46 are integrally fixed. It may be fixed by welding, brazing, screwing or the like.

A pinion shaft 47 that supports the pinion gear 43 is bridged between the carrier flange 45 and the carrier rim 46 and supported. A needle bearing 48 is disposed in the gap between the inner periphery of the pinion gear 43 and the outer periphery of the pinion shaft 47, and the pinion gear 43 is rotatable with respect to the pinion shaft 47. One end portion of the pinion shaft 47 inserted in the carrier flange 45 is prevented from rotating so as to have a predetermined phase with respect to the carrier flange 45 by a roller pin 49 press-fitted from the outside in the radial direction of the carrier flange 45. Has been. That is, the opening end of the lubrication hole formed inside the pinion shaft 47 is positioned so as to coincide with the opening end of the oil supply hole formed radially inside the carrier flange 45.

The carrier rim 46 is integrally formed with a cylindrical portion 46a that protrudes in the axial direction toward the front side (engine side), and an outer diameter portion of the clutch plate 51a of the direct coupling clutch 51 is formed on the inner peripheral portion of the cylindrical portion 46a. An inner spline 46b that engages with the spline is formed, and an outer spline 46c that engages with the inner diameter portion of the brake plate 50a of the reverse brake 50 is formed on the outer peripheral portion of the cylindrical portion 46a. As described above, the cylindrical portion 46 a serves as the brake hub of the reverse brake 50 and the clutch drum of the direct coupling clutch 51.

As shown in FIG. 2, the piston 50 b of the reverse brake 50 is disposed on the inner wall of the transmission case 5, and the piston 50 b is operated by the hydraulic pressure supplied between the piston 50 b and the transmission case 5. The brake plate (brake disc and brake plate) 50a can be fastened. As a reaction force member that supports the end of the brake plate 50a pressed by the pressure of the piston 50b, a cylindrical stopper portion 8a is integrally projected from the pump cover 8 that is a stationary member.

As shown in FIG. 3, the intermediate portion of the sun gear 41 is splined to the outer periphery of the flange portion 3 a formed integrally with the input shaft 3, and the clutch of the direct coupling clutch 51 is disposed on the front side (engine side) of the sun gear 41. A cylindrical portion 41a serving as a hub is integrally projected. The inner diameter portion of the clutch plate 51a of the direct coupling clutch 51 is spline engaged with the outer periphery of the cylindrical portion 41a. A gear portion 41 c that meshes with the pinion gear 43 is formed on the rear outer peripheral portion of the sun gear 41, and a ball bearing 57 is attached between the rear inner peripheral portion of the sun gear 41 and the inner peripheral portion outer peripheral surface of the carrier flange 45.

As shown in FIG. 3, a piston 51b having a U-shaped cross section is disposed on the rear surface side (opposite engine side) of the pump cover 8, and the clutch plate (clutch disk and clutch plate) 51a of the direct coupling clutch 51 is fastened by the piston 51b. Is done. A thrust bearing 52 is disposed between the clutch plate 51a and the piston 51b to transmit thrust while allowing relative rotation. Therefore, the axial pressure of the piston 51b is effectively transmitted to the clutch plate 51a, and the piston 51b is prevented from rotating with the clutch plate 51a. Since the side surface of the carrier rim 46 (pinion shaft 47) is located on the rear side of the clutch plate 51a via the cushion spring 56, the end portion of the clutch plate 51a pushed by the piston 51b is positioned on the carrier rim 46. And can eliminate the snap ring and special reaction force member.

Here, the direct coupling clutch 51, which is a stationary cylinder type clutch device, will be described in more detail with reference to FIGS.
The thrust bearing 52 includes a plurality of rollers 52a that are examples of rolling elements, and the rollers 52a are rotatably held by a race 52b via a retainer 52c. A cylindrical guide portion 52b _{1 which} is bent toward the piston direction and slidably contacts the inner peripheral surface of the inner spline 46b of the cylindrical portion 46a of the carrier rim 46 is integrally formed on the outer peripheral portion of the race 52b. Yes. Further, one or a plurality of claw pieces 52b ₂ project radially from the outer periphery of the race 52b. By engaging the claw pieces 52b ₂ with the inner splines 46b of the cylindrical portion 46a, the race 52b The rotation is prevented with respect to the cylindrical portion 46a. The race 52b has a larger area than the area S of the pressure contact portion of the clutch plate 51a, and the thrust transmitted from the piston 51b through the thrust bearing 52 acts on the entire surface of the pressure contact portion of the clutch plate 51a. be able to. In particular, the roller 52a is preferably disposed in the radial region S of the pressure contact portion of the clutch plate 51a, and more preferably, the center of the roller 52a and the center of the pressure contact portion of the clutch plate 51a are substantially matched. As a result, the thrust of the piston 51b is transmitted to the clutch plate 51a via the thrust bearing 52 without being offset in the radial direction, and the thrust of the piston 51b is transmitted to the clutch plate 51a without energy loss. Further, uneven wear of the thrust bearing 52 and the clutch plate 51a can be prevented.

A support plate 53 also serving as the other race of the thrust bearing 52 is disposed on the rear side surface of the piston 51b facing the roller 52a. The support plate 53 is made of a material having a higher strength than the piston 51b, and prevents the piston 51b from being deformed by contact with the roller 52a. In this example, the support plate 53 has an inner diameter bent in the axial direction, and is inlay-fitted to the inner diameter of the piston 51b. Therefore, the inclination of the support plate 53 can be suppressed and can be stabilized at a position along the rear side surface of the piston 51b. When the direct coupling clutch 51 is released, an axial gap δ is formed between the roller 52a and the support plate 53, which is smaller than the fitting allowance L between the race 52b and the cylindrical portion 46a. Therefore, a completely released state of the direct coupling clutch 51 can be obtained, and the thrust bearing 52 (roller 52a, race 52b) can be prevented from dropping from the cylindrical portion 46a.

A spring retainer 54 is fitted to the outer diameter portion of the direct coupling piston 51b, and a return spring 55 (see FIG. 2) is disposed between the outer peripheral end of the spring retainer 54 and the reverse brake piston 50b. . The springs 55 serve as return springs for both the direct clutch piston 51b and the reverse brake piston 50b, and an appropriate number of the springs 55 are provided on the outer peripheral side of the brake disk 50a of the reverse brake 50. Since the reverse brake 50 and the direct coupling clutch 51 are not actuated at the same time, one type of spring 55 can serve as both return springs.

In the above embodiment, the support plate 53 also serving as the other race is arranged on the side surface of the piston 51b. However, the other race may be constituted by the piston 51b itself. That is, it is possible to omit the other race by performing a surface treatment such as nitriding on the side surface of the piston 51b facing the clutch plate 51a or by forming the piston 51b itself from a high hardness material.

FIG. 5 shows a second embodiment of the present invention. The same parts as those in FIG.
In this embodiment, the inner diameter portion of the support plate 53 is extended in the axial direction along the inner diameter portion of the piston 51b, and the end portion of the extension portion 53a is set substantially at the same position as the end portion of the piston 51b. The pressure is pressed at 58. The other end surface of the return spring 58 is supported by a spring retainer 59 locked to the pump cover 8. In this case, since the support plate 53 is constantly pressed against the rear side surface of the piston 51b by the return spring 58, the axial position of the support plate 53 is stabilized.
Since the return spring 58 of this embodiment is dedicated to the direct coupling clutch 51, it is necessary to provide a separate return spring for the reverse brake 50.

FIG. 6 shows a third embodiment of the present invention. The same parts as those in FIG.
In this embodiment, the thrust bearing 52 includes a roller 52a, a holder 52c that rotatably holds the roller 52a, and a pair of races 52b and 52d that hold the holder 52c. In this case, since the pair of races 52b and 52d sandwiching both surfaces of the roller 52a are integrally assembled, the support plate 53 (see FIG. 3) disposed on the side surface of the piston 51b can be omitted. . When the direct coupling clutch 51 is released, an axial gap δ is formed between the race 52d and the piston 51b, which is smaller than the fitting allowance L between the race 52b and the drum 46a. Therefore, a completely released state of the direct coupling clutch 51 can be obtained, and the thrust bearing 52 (roller 52a, race 52b, 52d) can be prevented from falling off the drum 46a.

The present invention is not limited to the above embodiments.
In the embodiment of FIG. 3, the support plate 53 that also serves as the other race is disposed on the rear side surface of the piston 51b. However, the support plate 53 may also be used as the spring retainer 54 that is disposed on the outer periphery of the piston 51b. That is, one end of the spring retainer 54 may be extended in the inner diameter direction, and this extension may be used as a support plate.
In the above embodiment, an example in which the stationary cylinder type clutch device is applied to a direct coupling clutch in a forward / reverse switching device of a continuously variable transmission has been shown. However, it can be applied to a general clutch device used for an automatic transmission or the like. It is.

It is a skeleton figure of an example of a continuously variable transmission to which a stationary cylinder type clutch device concerning the present invention is applied. FIG. 2 is a detailed sectional view of the forward / reverse switching device of the continuously variable transmission shown in FIG. It is a detailed sectional view of a direct coupling clutch which is a stationary cylinder type clutch device. It is an expanded sectional view of a thrust bearing. It is sectional drawing of 2nd Example of the stationary cylinder type clutch apparatus concerning this invention. It is sectional drawing of 3rd Example of the stationary cylinder type clutch apparatus concerning this invention. It is sectional drawing of an example of the conventional stationary cylinder type clutch apparatus. It is sectional drawing of the other example of the conventional stationary cylinder type clutch apparatus.

Explanation of symbols

3 Input shaft 4 Forward / reverse switching device 8 Pump cover (stationary member)
41 Sun gear 41a Cylindrical part (hub)
44 Carrier 46 Carrier rim 46a Cylindrical part (drum)
46b Inner spline 51 Direct coupling clutch (stationary cylinder type clutch device)
51a Clutch plate 51b Piston 52 Thrust bearing 52a Roller (rolling element)
52b Race 52b ₁ Guide part 52b ₂ Claw piece 52c Cage 53 Support plate (the other race)

Claims (3)

The hub and drum constituting the input / output rotating member, the clutch plate disposed between the outer periphery of the hub and the inner periphery of the drum, and the stationary member movably disposed in the axial direction. In a stationary cylinder type clutch device comprising: a piston for fastening a plate; and a thrust bearing that is disposed between the piston and the clutch plate and transmits thrust while allowing relative rotation between the piston and the clutch plate.
The thrust bearing has at least one race and rolling elements rotatably held by the race,
The race is fitted to the inner periphery of the drum so as to be axially movable,
A stationary cylinder type clutch device, wherein an axial gap smaller than a fitting allowance between the race and the drum is formed between the thrust bearing and the piston when the clutch device is released. The cylindrical outer periphery of the said race is bent toward the piston direction, and the cylindrical guide part which touches the inner peripheral surface of the inner spline of the said drum slidably is formed. The stationary cylinder type clutch device described. 3. A stationary piece according to claim 1, wherein a claw piece is formed on an outer peripheral portion of the race so as to be fitted to an inner spline of the drum and prevent the race from rotating with respect to the drum. Cylinder type clutch device.

Images