JP2002195380A - Lockup device for fluid type torque transmission device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a lockup device for securing a plurality of friction surfaces by using a drive plate held between a piston and a front cover. SOLUTION: In this lockup device 7 of a torque converter 1, an annular driven plate 71 is fixed to a shell 30 of a turbine, and a disc-shaped part 71a for holding a plurality of torsion springs 73, a cylindrical part 71b, a first cut and raised part 71c, a second cut and raised part 71d for supporting both ends of rotating directions of the plurality of springs 73 and a projecting part 71e are provided. The drive plate 72 has a friction connecting part 72c adjacent to a friction surface 11b of the front cover 11, is movable in a shaft direction and is capable of performing torque transmission to the plurality of torsion springs 73. The piston 74 is engaged to the front cover 11 so as to be relatively non-rotatable and movable in the shaft direction to be movable in the shaft direction by hydraulic pressure and is a member for pressing the friction connecting part 72c on the friction surface 11b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock-up device for a hydraulic torque transmitting device, and more particularly, to a drive plate having a frictional connection portion close to a front cover, and a piston capable of pressing the drive plate against the front cover. And a lock-up device having the lock-up device.

[0002]

2. Description of the Related Art A torque converter is a type of fluid torque transmission device having three types of impellers (impeller, turbine, and stator) inside and transmitting torque through internal working oil. The impeller is fixed to a front cover as an input-side rotating body. The turbine is located opposite the impeller in the fluid chamber. When the impeller rotates, hydraulic oil flows from the impeller to the turbine, and outputs torque by rotating the turbine.

[0003] The lock-up device is disposed in a space between the turbine and the front cover, and is a mechanism for directly transmitting torque from the front cover to the turbine by mechanically connecting the front cover and the turbine. .

Normally, this lock-up device has a disk-shaped piston that can be pressed against a front cover, a retaining plate fixed to the outer peripheral portion of the piston, and a rotational direction and an outer peripheral side by the retaining plate. It has a torsion spring that is supported and a driven plate that supports both ends of the torsion spring in the rotation direction. The driven plate is fixed to a turbine shell or the like of the turbine.

[0005] When the lock-up device is connected, torque is transmitted from the front cover to the piston, and further transmitted to the turbine via the torsion spring.
Also, in the elastic coupling mechanism of the lock-up device, the torsion spring is compressed in the rotational direction between the retaining plate and the driven member to absorb torsional vibration.
Decay.

[0006]

Further, as a lockup device having two friction surfaces to increase the torque transmission capacity, a damper mechanism connected to a turbine and an input portion of the damper mechanism are relatively non-rotatable. Some have a drive plate locked to be movable in the axial direction, and a piston for urging the frictional connection portion of the drive plate to the piston.

The lock-up device disclosed in Japanese Patent Application Laid-Open No. 11-509611 discloses a damper plate 18 fixed to a turbine hub, a coil spring 16 supported at both ends in the rotational direction, a coil spring 16 and a coil spring 16. Guide ring 1 engaged with both ends in the rotation direction
2, a disk 10 engaged with the disk 2 so as to be relatively non-rotatable and movably in the axial direction, and a piston 1 for urging the disk 10 against the front cover 2. In this structure, the damper plate 18 is fixed to the turbine hub, and the guide ring 12 is provided to support the coil spring 16, so that the total number of components is large and the structure is complicated.

In the lock-up device disclosed in Japanese Patent Application Laid-Open No. H10-47453, a damper hub 18 fixed to a turbine hub, a compression spring 23 disposed in a window hole thereof, and disposed on both axial sides of the damper hub 18. It has a pair of drive plates 17, a friction plate 13 that cannot rotate relative thereto and is movable in the axial direction, and a piston 14 for urging the friction plate 13 against the converter cover 1. In this structure, the damper hub 18 is fixed to the turbine hub, and a pair of drive plates 17 is used to support the compression spring 23.
Is provided, so that the number of parts is large and the structure is complicated.

Further, the disk 10 of the lock-up device disclosed in Japanese Patent Publication No. 11-509611 and Japanese Patent Application Laid-Open
The friction plate 13 of the lock-up device disclosed in Japanese Patent Application No. 0-47553 is capable of moving in the radial direction and tilting within a predetermined range.

An object of the present invention is to simplify the structure of a lock-up device that secures a plurality of friction surfaces by using a drive plate sandwiched between a piston and a front cover.

Another object of the present invention is to stabilize the position or posture of a drive plate in a lockup device that secures a plurality of friction surfaces by using a drive plate sandwiched between a piston and a front cover.

[0012]

According to a first aspect of the present invention, there is provided a lock-up device including a front cover having a friction surface to which a torque from an engine is input, an impeller fixed to the front cover to form a fluid chamber, and a fluid chamber. And a turbine that is arranged to face the impeller and outputs torque to the transmission, and is used for a fluid torque transmission device that transmits torque from the engine to the transmission. The lockup device is a device disposed between the turbine and the front cover, and includes a plurality of elastic members, an annular driven plate, a drive plate, and a piston. The plurality of elastic members are arranged side by side in the rotation direction. The annular driven plate is fixed to the shell of the turbine, and has a holding portion that holds the plurality of elastic members, and a supporting portion that supports both ends of the plurality of elastic members in the rotation direction. The drive plate has a friction coupling portion close to the friction surface of the front cover, is movable in the axial direction, and is capable of transmitting torque to a plurality of elastic members. The piston is non-rotatably and axially movably engaged with the front cover, is axially movable by hydraulic pressure, and is a member for pressing the friction coupling portion against the friction surface.

[0013] In this lockup device, the annular driven plate is fixed to the shell of the turbine and holds a plurality of elastic members. Therefore, the structure of the entire device is simplified.

According to a second aspect of the present invention, in the lock-up device for a hydraulic torque transmission device, the holding portion of the driven plate according to the first aspect is an annular and disk-shaped member disposed on the axial transmission side of the plurality of elastic members. And a cylindrical outer-side support portion extending from the outer peripheral edge of the axial-direction support portion to the engine side in the axial direction and positioned on the outer-peripheral side of the plurality of elastic members. The drive plate has an annular disk-shaped portion formed on the outer peripheral side of the frictional connection portion, and an inner peripheral surface abutting on the outer peripheral surface of the cylindrical portion of the driven plate extending in the axial direction from the outer peripheral edge of the disk-shaped portion. And an outer peripheral side cylindrical portion supported and supported.

In this lockup device, the drive plate is supported by the driven plate in the radial direction, so that the position in the radial direction is stabilized. According to a third aspect of the present invention, in the lock-up device for a hydraulic torque transmission device, the first and second drive plates are configured such that the drive plate abuts on both ends in the rotational direction of the plurality of elastic members so as to be movable in the axial direction. Having.

In this lock-up device, since the drive plate is directly engaged with the elastic member without any intervening members, the number of components is reduced as a whole. The lock-up device according to claim 4, wherein a transmission is disposed opposite to the impeller in the fluid chamber, a front cover having a friction surface to which torque from the engine is input, the impeller being fixed to the front cover, and a fluid chamber. And a turbine that outputs torque to the transmission, and is used for a hydraulic torque transmission device that transmits torque from an engine to a transmission. The lockup device is a device disposed between the turbine and the front cover, and includes a plurality of elastic members, a driven plate, a drive plate, and a piston. The plurality of elastic members are arranged side by side in the rotation direction. The driven plate is fixed to the turbine, and receives torque from a plurality of elastic members. The drive plate has a friction coupling portion close to the friction surface of the front cover, and is capable of transmitting torque to a plurality of elastic members. The piston is non-rotatably and axially movably engaged with the front cover, is axially movable by hydraulic pressure, and is a member for pressing the friction coupling portion against the friction surface. The drive plate is positioned in the radial direction by a driven plate.

In this lock-up device, the drive plate is supported by the driven plate in the radial direction, so that the position in the radial direction is stabilized. The lock-up device according to claim 5, wherein a transmission is arranged to face the impeller in the fluid chamber, a front cover fixed to the front cover to form a fluid chamber, a front cover having a friction surface to which a torque from the engine is input, and a fluid chamber. And a turbine that outputs torque to the transmission, and is used for a hydraulic torque transmission device that transmits torque from an engine to a transmission. The lockup device is a device disposed between the turbine and the front cover, and includes a plurality of elastic members, a driven plate, a drive plate, and a piston. The plurality of elastic members are arranged side by side in the rotation direction. The driven plate is fixed to the turbine, and receives torque from a plurality of elastic members. The drive plate has a friction coupling portion close to the friction surface of the front cover, and is capable of transmitting torque to a plurality of elastic members. The piston is non-rotatably and axially movably engaged with the front cover, is axially movable by hydraulic pressure, and is a member for pressing the friction coupling portion against the friction surface. The drive plate has a plurality of abutting portions that abut axially movably on both ends in the rotational direction of the plurality of elastic members.

In this lock-up device, since the drive plate is directly engaged with the elastic member without any intervening members, the total number of components is reduced.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment (FIGS. 1 to 5) (1) Basic Structure of Torque Converter FIG. 1 is a schematic longitudinal sectional view of a torque converter 1 according to an embodiment of the present invention. The torque converter 1 is a device for transmitting torque from a crankshaft 2 of an engine to an input shaft 3 of a transmission.
An engine (not shown) is arranged on the left side of FIG. 1, and a transmission (not shown) is arranged on the right side of FIG.
OO shown in FIG. 1 is a rotation shaft of the torque converter 1.

The torque converter 1 mainly includes a flexible plate 4 and a torque converter body 5. The flexible plate 4 is a thin disk-shaped member that transmits torque and absorbs bending vibration transmitted from the crankshaft 2 to the torque converter body 5. Therefore, the flexible plate 4 has sufficient rigidity for transmitting torque in the rotation direction, but has low rigidity in the bending direction.

The torque converter main body 5 is composed of a torus-shaped fluid working chamber 6 composed of three types of impellers (impeller 21, turbine 22, and stator 23), and a lock-up device 7.

The front cover 11 is a disk-shaped member, and is disposed close to the flexible plate 4. A center boss 16 is provided on the inner peripheral end of the front cover 11.
Are fixed by welding. The center boss 16 is a cylindrical member extending in the axial direction, and is inserted into a center hole of the crankshaft 2.

The center boss 16 is, as shown in FIG.
It is composed of a cylindrical portion 16a and a flange 16b. A bottom 16c is formed on the engine side of the cylindrical portion 16a in the axial direction. Further, the inner peripheral surface of the axial transmission side portion of the cylindrical portion 16a is
The input shaft 3 is rotatably supported. Further, a seal ring 92 is arranged on the bush 91 on the engine side in the axial direction. The seal ring 92 is disposed in an annular groove formed on the inner peripheral surface of the cylindrical portion 16a, and is in contact with the outer peripheral surface at the tip of the input shaft 3.

The flange 16b is formed on the outer peripheral surface of the cylindrical portion 16a, and is disposed in contact with the axial side surface of the inner peripheral portion of the front cover 11 in the engine. In this state, the center boss 16 is fixed to the front cover 11 by welding. In that sense, the center boss 16 may be regarded as a part of the front cover.

The center boss 16 is formed with a plurality of communication passages 16d communicating the inside and outside in the radial direction. Each communication path 16d is a hole extending in the radial direction in the cylindrical portion 16a. In addition, each communication passage 16d is provided with a flange 16
In FIG. 2B, a radially extending groove formed on the side surface of the engine in the axial direction forms a passage between the groove and the front cover 11. The space on the inner peripheral side of the center boss 16, that is, the center hole 3a of the input shaft 3, communicates with the outer peripheral side of the center boss 16, that is, the space 9 in the fluid chamber by the communication passage 16d. This communication path 16d is hereinafter referred to as the first
Port 17 is assumed.

The inner peripheral portion of the flexible plate 4 is fixed to the distal end surface of the crankshaft 2 by a plurality of bolts 13. A plurality of nuts 12 are fixed to the outer peripheral side of the front cover 11 and the engine side surface at equal intervals in the circumferential direction. Bolts 14 screwed into the nuts 12 cover the outer periphery of the flexible plate 4 with the front cover 11.
It is fixed to.

An outer peripheral side cylindrical portion 11a extending toward the transmission in the axial direction is formed on the outer peripheral portion of the front cover 11. The outer peripheral edge of the impeller shell 26 of the impeller 21 is fixed to the tip of the outer peripheral side cylindrical portion 11a by welding. As a result, a fluid chamber filled with hydraulic oil is formed by the front cover 11 and the impeller 21. The impeller 21 mainly includes an impeller shell 26, a plurality of impeller blades 27 fixed inside the impeller shell 26, and an impeller hub 28 fixed to an inner peripheral portion of the impeller shell 26.

The turbine 22 is provided in the fluid chamber in the impeller 21.
And are arranged to face each other in the axial direction. The turbine 22
It mainly includes a turbine shell 30, a plurality of turbine blades 31 fixed to a surface on the impeller side thereof, and a turbine hub 32 fixed to an inner peripheral edge of the turbine shell 30. Turbine shell 30 and turbine hub 3
2 is fixed by a plurality of rivets 33.

A spline engaging with the input shaft 3 is formed on the inner peripheral surface of the turbine hub 32. Thus, the turbine hub 32 rotates integrally with the input shaft 3.

The stator 23 is a mechanism for rectifying the flow of hydraulic oil returning from the turbine 22 to the impeller 21. The stator 23 is a member integrally manufactured by casting with a resin, an aluminum alloy, or the like. Stator 23 is arranged between the inner peripheral portion of impeller 21 and the inner peripheral portion of turbine 22. The stator 23 mainly includes an annular stator carrier 35 and a plurality of stator blades 36 provided on the outer peripheral surface of the carrier 35. The stator carrier 35 is supported on a cylindrical fixed shaft 39 via a one-way clutch 37. The fixed shaft 39 extends between the outer peripheral surface of the input shaft 3 and the inner peripheral surface of the impeller hub 28. Although the one-way clutch 37 shown in the figure has a structure using a ratchet, it may have a structure using rollers and sprags.

The torus-shaped fluid working chamber 6 is formed in the fluid chamber by the shells 26, 30, and 35 of the impellers 21, 22, and 23 described above. An annular space 9 is provided between the front cover 11 and the fluid working chamber 6 in the fluid chamber.

A first thrust bearing 41 is arranged between the center boss 16 and the turbine hub 32 in the axial direction. Further, a second space is provided between the turbine hub 32 and the inner peripheral portion of the stator 23 (specifically, the one-way clutch 37).
A thrust bearing 42 is arranged. In the portion where the second thrust bearing 42 is disposed, the second port 18 through which the hydraulic oil can communicate is formed on both sides in the radial direction. That is, the second port 18 communicates the oil passage between the input shaft 3 and the fixed shaft 39 with the fluid working chamber 6. Further, a third thrust bearing 43 is arranged between the stator 23 (specifically, the carrier 35) and the impeller 21 (specifically, the impeller hub 28) in the axial direction. This third thrust bearing 4
In the portion where 3 is arranged, third ports 19 through which hydraulic oil can communicate are formed on both sides in the radial direction. That is, the third port 19 allows the oil passage between the fixed shaft 39 and the impeller hub 28 to communicate with the fluid working chamber 6. In addition, each oil passage is connected to a hydraulic circuit (not shown), and supply and discharge of hydraulic oil to the first to third ports 17 to 19 can be performed independently. (2) Structure of Lock-Up Device The lock-up device 7 is disposed in the space 9 between the turbine 22 and the front cover 11, and is a mechanism for mechanically connecting the two as necessary. The lock-up device 7 is disposed in a space between the front cover 11 and the turbine 22 in the axial direction.

The lock-up device 7 has the functions of a clutch and an elastic coupling mechanism, and mainly includes a driven plate 71.
, A drive plate 72, a plurality of torsion springs 73, a piston 74, and a piston connection mechanism 75.

The driven plate 71 is an annular plate member as shown in FIGS. 2 and 4, and is fixed to the outer peripheral side of the turbine shell 30. Driven plate 71
Is mainly composed of a disc-shaped portion 71a (axial support portion) and a tubular portion 71b (outer peripheral support portion) extending from the outer peripheral edge toward the engine in the axial direction. The disc-shaped portion 71a is fixed to the turbine shell 30 by welding. The tubular portion 71b extends substantially straight in the axial direction, but has a shape in which the tip is bent inward.

The disk-shaped portion 71a has a plurality of first cut-and-raised portions 71c cut and raised in the axial direction.
The first cut-and-raised portions 71c are formed side by side in the rotation direction, and are arranged with a gap on the inner peripheral side of the tubular portion 71b. A plurality of second cut-and-raised portions 71d cut and raised in the axial direction are formed on the disc-shaped portion 71a. The second cut-and-raised portions 71d are arranged between the rotation directions of the first cut-and-raised portions 71c, and are located on the outer peripheral side of the radial position of the first cut-and-raised portions 71c. Further, the cylindrical portion 71
In b, a protruding portion 71e is formed at a portion corresponding to the second cut-and-raised portion 71d so as to protrude inward by drawing.

Each pair of the second cut-and-raised portion 71d and the protruding portion 71e has a function as a torque transmitting portion, and each of the torque transmitting portions is a spring accommodating portion between the rotation directions. In this embodiment, six spring accommodating portions are formed.

In the present embodiment, the torsion springs 73 are a plurality of (six) coil springs extending in the circumferential direction. The torsion spring 73 is held by the driven plate 71. In particular,
Each torsion spring 73 is accommodated in each spring accommodating portion, and the radial inner side is supported by the outer peripheral surface of the first cut-and-raised portion 71c, and the radial outer side is supported by the inner peripheral surface of the cylindrical portion 71b. In addition, the end of each torsion spring 73 in the rotation direction is directly or through a spring seat, and a second cut-and-raised portion 71d as a torque transmitting portion
And is supported in contact with or close to the protruding portion 71e.
Further, the transmission side surface of each torsion spring 73 in the axial direction is supported by a disc-shaped portion 71a. Further, the bent portion at the tip of the cylindrical portion 71b also abuts against the axial engine side surface on the outer peripheral side of the torsion spring 73, thereby preventing the torsion spring 73 from dropping from the driven plate 71 to the axial engine side. ing. Thus, in the lock-up device 7, the annular driven plate 71 is
And holds a plurality of torsion springs 73. Therefore, the number of parts is reduced, the structure of the entire apparatus is simplified, and the overall weight is reduced.

The drive plate 72 is a member capable of inputting torque to the torsion spring 73, and is also a frictional connection member that connects to and separates from the front cover 11. The drive plate 72 is an annular and disk-shaped plate member.
1 and the front cover 11. The drive plate 72 mainly includes an annular disc-shaped main body 72a.
And a tubular portion 72b (outer peripheral tubular portion) extending from the outer peripheral edge toward the transmission in the axial direction. The inner peripheral portion of the disk-shaped main body 72a is a friction coupling portion 72c, and the outer peripheral portion is a pressure receiving portion 72d (a disk-shaped portion).
The frictional connection portion 72c has an annular and flat disk shape,
It is close to the friction surface 11b of the front cover 11. Also, friction facings 72 are provided on both surfaces of the frictional connection portion 72c.
e is affixed. The pressure receiving portion 72d has an annular and flat disk shape, and is arranged on the engine side of the torsion spring 73 in the axial direction. The cylindrical portion 72b is located on the outer peripheral side of the cylindrical portion 71b of the driven plate 71, and the inner peripheral surface of the cylindrical portion 72b is in contact with the outer peripheral surface of the cylindrical portion 71b. Accordingly, the drive plate 72 can move in the axial direction and the rotation direction with the drive plate 72 positioned in the radial direction with respect to the driven plate 71. Therefore, the position and posture of the drive plate 72 are stabilized.
In particular, since the drive plate 72 is supported by the driven plate 71 by abutting (inlay) between the cylindrical portions, the drive plate 72 is hardly inclined. As a result, the parallelism of the friction connecting portion 72c of the drive plate 72 with respect to the friction surface 11b of the front cover 11 and the pressing portion 74a of the piston 74 can be maintained high. That is, when the clutch is engaged, the pressing force acts evenly on the entire friction facing 72e, and drag torque hardly occurs when the clutch is released.

Further, a plurality of claws 72f (contact portions) are formed on the drive plate 72. Claw part 72f
Are formed by cutting and raising the pressure receiving portion 72d toward the transmission in the axial direction, and are formed at equal intervals in the rotational direction. The claw portion 72f is inserted between the second cut-and-raised portion 71d and the protruding portion 71e in the radial direction from the engine side, and both ends in the rotation direction abut directly on the both ends in the rotation direction of each torsion spring 73 or via a spring seat. Or close. The claw portion 72f rotates relative to the driven plate 71 to rotate the second cut-and-raised portion 71d and the protruding portion 71e.
Can compress the torsion spring 73.
In this lockup device 7, the drive plate 72 is directly engaged with the torsion spring 73 without any intervening other members (plates), so that the total number of parts is reduced.

The drive plate 72 is movable in the axial direction. Specifically, the drive plate 72 is moved in the axial direction until the friction facing 72e of the friction coupling portion 72c on the engine side contacts the friction surface 11b. On the transmission side, the outermost peripheral portion of the pressure receiving portion 72d is a driven plate 7
It is movable until it comes into contact with one cylindrical portion 71b.

In the structure of the drive plate 72 described above, a pressure receiving portion 72d is formed on the outer periphery of the frictional connection portion 72c. The pressure receiving portion 72d extends further to the outer peripheral side than the outer peripheral edge of the piston 74, and further extends to the outer peripheral side than the driven plate 71, and functions as a portion of the drive plate 72 that receives the hydraulic pressure in the space 9.
In other words, the pressure receiving portion 72d is
The pressure receiving area is increased, and the piston function is improved. Therefore, when the clutch is engaged, the hydraulic pressure
In addition, the drive plate 72 acts on the drive plate 72 so that the drive plate 72 quickly moves to the friction surface 11 of the front cover 11.
Move to b side. In other words, the lock-up response of the lock-up device 7 is improved.

The piston 74 is a member for connecting and disconnecting the clutch. The piston 74 has a disk shape with a center hole formed. The outer peripheral portion of the piston 74 is located on the inner peripheral side of the torsion spring 73, and the inner peripheral portion is located on the outer peripheral side of the center boss 16. The outer peripheral portion of the piston 74 is a pressing portion 74a. The pressing portion 74 a is a flat annular portion, and the friction connecting portion 72 of the drive plate 72 is formed.
c is disposed on the transmission side in the axial direction. Therefore, when the piston 74 moves toward the engine in the axial direction, the pressing portion 74a presses the friction connecting portion 72c against the friction surface 11b of the front cover 11.

Next, the piston connecting mechanism 75 will be described. The piston connection mechanism 75 has a function of connecting the piston 74 so as to rotate integrally with the front cover 11 while being movable in the axial direction.

The specific structure of the piston connection mechanism 75 will be described below with reference to FIGS. A cylindrical portion 74b extending in the axial direction is formed on the inner peripheral portion of the piston 74. The inner peripheral surface of the cylindrical portion 74b is the center boss 16
Is in contact with the outer peripheral surface of the flange 16b. In addition, a seal ring 80 is provided on the outer peripheral surface of the flange 16b to be in contact with the inner peripheral surface of the cylindrical portion 74b. This allows
Both sides in the axial direction are sealed between the inner peripheral portion of the piston 74 and the outer peripheral portion of the center boss 16.

Further, on the inner peripheral portion of the piston 74, an inner peripheral disc-shaped portion 74c is formed extending from the distal end of the cylindrical portion 74b on the transmission side in the axial direction to the inner peripheral side. The inner peripheral disc-shaped portion 74c is disposed on the axial transmission side of the flange 16b. A plurality of holes 74d are formed in the disc-shaped portion 74c so as to be arranged in the rotation direction. Also,
The flange 16b has an axial through hole 16e corresponding to the position, shape, and size of the hole 74d.
The body 81a of the pin 81 extending in the axial direction is inserted and penetrates into the holes 74d and 16e. The body portion 81a extends straight in the axial direction, and the piston 74 is
On the other hand, it cannot move in the rotation direction and the radial direction, but can move in the axial direction. That is, torque is transmitted from the pin 81 to the piston 74.

In the pin 81, a first head portion 81b is formed on the body portion 81a on the engine side in the axial direction. The first head portion 81b has a larger diameter than the axial through hole 16e, and has a communication passage 16 formed on the flange 16b on the engine side in the axial direction.
It is located in a groove that is part of d. As a result, the pin 81 cannot move toward the transmission in the axial direction with respect to the flange 16b. Further, in the pin 81, a neck portion 81c and a second head portion 81d are formed at an end of the trunk portion 81a on the side in the axial transmission direction. Neck 81
c is smaller in diameter than the trunk 81a. Also, the second head 81d
Has a larger diameter than the neck 81c and the same diameter as the body 81a.

A wiring 8 is provided on the inner peripheral side of the neck 81c.
2 are arranged. The wiring 82 is an annular member having a circular cross section. The outer peripheral portion of the wiring 82 is sandwiched between the body portion 81a and the second head portion 81d on the inner peripheral side of the neck portion 81c, so that the wiring 82 cannot move in the axial direction with respect to the pin 81. Further, the inner peripheral side portion of the wiring 82 can be brought into contact with the axial transmission side surface of the inner peripheral disc-shaped portion 74 c of the piston 74. As described above, the wiring 82 is
4 restricts the movement of the pin 81 toward the transmission in the axial direction. As a result, axial movement of the piston 74, especially its inner disk portion 74c, is allowed only between the axial direction of the flange 16b and the wiring 82.

As described above, the pin 81 extending in the axial direction and the piston 74 having the hole 74d into which the pin 81 fits are provided.
Thus, the structure of the piston coupling mechanism 75 is simpler than that of the related art. For example, a conventional piston connection mechanism using a strap rate requires riveting or bolting, so that the assembly process is complicated and the number of processes is very large. Therefore, the manufacturing cost is high. Further, the conventional structure has a problem that the weight is large. On the other hand, in the piston connection mechanism according to the present invention, the assembly is simple, the number of steps can be greatly reduced, and the weight can be further reduced.

The assembly of the pin 81, the wiring 82 and the piston 74 will be described. First, the pin 81 is inserted into the hole 16e of the flange 16b of the center boss 16 from the communication passage 16d side. In this state, the center boss 16 is fixed to the front cover 11 by welding. As a result, the pin 81 is integrated with the front cover 11 together with the center boss 16. Next, the inner disk-like portion 74c of the piston 74
Closer to the second head 81d of the pin 81,
The second head 81d and the neck 81c are passed through the hole 16e, and the body 81a is fitted into the hole 16e. Finally, the wiring 82 is fitted into the neck 81c of the pin 81.

In the assembling process described above, each member is performed in a simple process of moving only in the axial direction. Therefore, the working process is simplified and the manufacturing cost is reduced. Further, since the wiring 82 can be easily attached to the pin 81, workability is good.

Although the pin 81 described above is a cylindrical stud pin, it may have another shape or a member extending in another axial direction. The cone spring 83
This is a member for applying a biasing force to the piston 74 on the transmission side in the axial direction, that is, on the clutch release side. The cone spring 83 is arranged between the front cover 11 and the inner peripheral portion of the piston 74, and is compressed in the axial direction at least in a clutch connected state. More specifically, the cone spring 83 has an inner peripheral edge in contact with the front cover 11 and an outer peripheral edge in contact with the inner peripheral portion of the piston 74. The inner peripheral edge of the cone spring 83 is in contact with the outer peripheral surface of the flange 16b and is supported in the radial direction. Note that another spring such as a wave spring may be used instead of the cone spring. (3) Operation of Torque Converter Immediately after starting the engine, hydraulic oil is supplied into the torque converter main body 5 from the first port 17 and the third port 19, and hydraulic oil is discharged from the second port 18. The hydraulic oil supplied from the first port 17 flows between the front cover 11 and the piston 74 toward the outer periphery. The hydraulic oil further flows through both sides of the drive plate 72 in the axial direction, and finally flows into the fluid working chamber 6. At this time, the oil pressure on the front cover 11 side becomes higher than the oil pressure on the turbine 22 side of the piston 74, and the piston 74 moves toward the transmission in the axial direction by the urging force of the cone spring 83. The piston 74 stops in a state where the inner disk-shaped portion 74c is in contact with the wiring 82.

The drive plate 72 is in contact with the cylindrical portion 71b of the driven plate 71, so that movement on the transmission side in the axial direction is restricted. Therefore, in the clutch connected state, the frictional connection portion 7 of the drive plate 72
A gap is provided between 2c and the pressing portion 74a of the piston 74. Therefore, drag torque hardly occurs.

When the lock-up is released as described above, the torque transmission between the front cover 11 and the turbine 22 is performed by the fluid drive between the impeller 21 and the turbine 22. (4) Operation of lockup device The speed ratio of the torque converter 1 increases, and the input shaft 3
Reaches a certain number of rotations, the space 9
Hydraulic oil inside is discharged. As a result, the hydraulic pressure of the piston 74 on the turbine 22 side becomes higher than the hydraulic pressure on the front cover 11 side, the piston 74 is moved to the front cover 11 side, and the pressing portion 74a connects the friction connecting portion 72c of the drive plate 72 to the front cover 11. To the friction surface 11b. Also, as described above, the drive plate 72
Is the friction surface 1 by the hydraulic pressure acting on the pressure receiving portion 72d.
It has moved to 1b side. As a result, the front cover 11
Is transmitted from the drive plate 72 to the driven plate 71 via the torsion spring 73. Further, the torque is transmitted from the driven plate 71 to the turbine 22. That is, the front cover 11 is mechanically connected to the turbine 22, and the torque of the front cover 11 is directly output to the input shaft 3 via the turbine 22. In addition, the friction coupling portion 7 of the drive plate 72
Since both surfaces of 2c are friction surfaces, the torque transmission capacity is larger than that of a lockup device having a single friction surface. Second Embodiment (FIG. 6) In the second embodiment shown in FIG.
Is the same as that of the above embodiment. Hereinafter, only different points from the first embodiment will be mainly described.

In the piston connecting mechanism 75, the cylindrical portion of the above embodiment is not formed on the inner peripheral portion of the piston 74. Instead, a cylindrical portion 74g extending toward the engine in the axial direction is formed around a hole 74f formed in the inner peripheral portion of the piston 74. Also, the body 81 of each pin 81
A seal ring 94 is arranged on the outer peripheral surface of each a, and is in contact with the inner peripheral surface of the cylindrical portion 74g. That is, in the embodiment, the piston and the center boss flange seal axially in the inner peripheral portion of the piston, but in the present embodiment, the piston and the plurality of pins seal axially in the inner peripheral portion of the piston. ing.

Further, the cone spring 83 is disposed between the flange 16b and the inner periphery of the piston 74. More specifically, the outer peripheral edge of the cone spring 83 is in contact with the flange 16b, and the inner peripheral edge is in contact with the tip of each tubular portion 74g. The inner peripheral edge of the cone spring 83 is supported in contact with the outer peripheral portion of the body 81 a of the pin 81. [Other Embodiments] The lock-up device according to the present invention can be applied to not only a torque converter but also other fluid type torque transmission devices such as a fluid coupling.

In the above-described embodiment, a pin is used for the piston connecting mechanism, but any member may be used as long as it is a member extending in the axial direction.

[0057]

In the lockup device according to the present invention, the annular driven plate is fixed to the turbine shell,
It holds a plurality of elastic members. Therefore, the structure of the entire device is simplified.

[Brief description of the drawings]

FIG. 1 is a schematic longitudinal sectional view of a torque converter to which an embodiment of the present invention is applied.

FIG. 2 is a partially enlarged view of FIG. 1, showing a damper mechanism of the lock-up device.

FIG. 3 is a partially enlarged view of FIG. 1, showing a piston coupling mechanism.

FIG. 4 is an exploded perspective view of a drive plate and a driven plate.

FIG. 5 is a perspective view in which a part of a piston connection mechanism is broken.

FIG. 6 is a diagram corresponding to FIG. 3 in a second embodiment.

[Explanation of symbols]

 7 Lock-up device 11 Front cover 71 Driven plate 72 Drive plate 73 Torsion spring 74 Piston 75 Piston coupling mechanism

Claims (5)

[Claims] A front cover having a friction surface to which a torque from an engine is input, an impeller fixed to the front cover to form a fluid chamber, and a transmission disposed in the fluid chamber to face the impeller and transmitting torque to a transmission. A hydraulic turbine for transmitting torque from the engine to a transmission, the lock-up device being disposed between the turbine and the front cover, the lock-up device being disposed side by side in the rotational direction. A plurality of elastic members, an annular driven plate fixed to the shell of the turbine and holding the plurality of elastic members, and a support portion supporting both ends in the rotational direction of the plurality of elastic members, A friction coupling portion adjacent to the friction surface of the front cover, and movable in an axial direction; A drive plate capable of transmitting torque to the plurality of elastic members; a drive plate capable of being relatively non-rotatably and axially movably engaged with the front cover; being axially movable by hydraulic pressure; And a piston for pressing the frictional surface against the friction surface. 2. The holding portion of the driven plate includes an annular and disk-shaped axial support portion disposed on the axial transmission side of the plurality of elastic members, and a shaft extending from an outer peripheral edge of the axial support portion. A cylindrical outer peripheral support portion extending toward the engine side and located on the outer peripheral side of the plurality of elastic members, wherein the drive plate has an annular disk formed on the outer peripheral side of the friction coupling portion. And a peripheral cylindrical portion extending in the axial direction from the outer peripheral edge of the disk-shaped portion and having an inner peripheral surface in contact with and supported by the outer peripheral surface of the cylindrical portion of the driven plate. The lock-up device for a hydraulic torque transmission device according to claim 1, wherein 3. The fluid torque transmission device according to claim 1, wherein the drive plate has a plurality of contact portions that movably contact in the axial direction with both ends of the plurality of elastic members in the rotation direction. Lock-up device. 4. A front cover having a friction surface to which a torque is input from an engine, an impeller fixed to the front cover to form a fluid chamber, and a transmission arranged in the fluid chamber to face the impeller and transmitting torque to a transmission. A hydraulic turbine for transmitting torque from the engine to a transmission, the lock-up device being disposed between the turbine and the front cover, the lock-up device being disposed side by side in the rotational direction. A plurality of elastic members, a driven plate fixed to the turbine, to which torque is input from the plurality of elastic members, and a friction coupling portion close to the friction surface of the front cover, the plurality of elastic members Drive plate capable of transmitting torque to the front cover and relative rotation to the front cover It engaged to be movable in the axial direction and the ability is movable in the axial direction by a hydraulic,
A piston for pressing the frictional connection portion against the frictional surface, wherein the drive plate is radially positioned by the driven plate. 5. A front cover having a friction surface to which a torque from an engine is inputted, an impeller fixed to the front cover to form a fluid chamber, and a transmission arranged in the fluid chamber to face the impeller and transmitting torque to a transmission. A hydraulic turbine for transmitting torque from the engine to a transmission, the lock-up device being disposed between the turbine and the front cover, the lock-up device being disposed side by side in the rotational direction. A plurality of elastic members, a driven plate fixed to the turbine, to which torque is input from the plurality of elastic members, and a friction coupling portion close to the friction surface of the front cover, the plurality of elastic members Drive plate capable of transmitting torque to the front cover and relative rotation to the front cover A piston for movably and axially movably engaging and being axially movable by hydraulic pressure, and for pressing the frictional connection portion against the frictional surface, wherein the drive plate includes a plurality of elastic members. A lock-up device for a fluid torque transmission device, comprising a plurality of contact portions that are movably contacted in the axial direction at both ends in the rotation direction.