JPH0874963A - Hydraulic power transmission gear - Google Patents

Abstract

PURPOSE: To make torque capacity sufficiently large as well as to reduce costs by decreasing the number of parts and reducing the weight. CONSTITUTION: A hydraulic power transmission gear is provided with a lockup clutch piston 21 arranged so as to face a front cover 16, and provided with a claw part 21a and a lightening hole 21a formed by punching the vicinity of the outer peripheral edge, a driven plate 32 to be rotated together with a turbine runner 12, and a spring 33 wherein one end surface is locked on the claw part 21a, and the other end surface is locked on the driven plate 32, and for absorbing the fluctuation of transmission torque. On one surface where the lockup clutch piston 21 and the front cover 16 are faced to each other, a first lining for forming an uncontinuous friction surface in the radial position facing the lightening hole 21b, and a second lining for forming a seal surface continued inward in the radial direction from the lightening hole 21b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic power transmission device having a lockup clutch device.

[0002]

2. Description of the Related Art Conventionally, an automatic transmission is provided with a torque converter as a fluid transmission device, and has a structure for transmitting the rotation of an engine taken out by a crankshaft to an input shaft of a transmission mechanism via the torque converter. There is.
The torque converter includes a pump impeller, a turbine runner, a stator, a lockup clutch device, and a damper device. Then, the rotation from the engine is transmitted to the pump impeller through the front cover,
The turbine runner is rotated by the flow of oil generated by the rotation of the pump impeller, and the rotation of the turbine runner is transmitted to the input shaft.

In this case, when the vehicle speed set in advance is obtained after the vehicle has started, the lockup clutch device is engaged and the rotation of the engine is transmitted to the input shaft without passing through the torque converter. Therefore, the lock-up clutch device has a lock-up clutch piston and an annular friction material that is crimped in the vicinity of the outer peripheral edge of the lock-up clutch piston, and when the lock-up clutch device is engaged, the lock-up clutch piston is It is moved to the front cover side so that the friction material and the front cover are frictionally engaged with each other.

By the way, when the rotation from the engine is transmitted to the input shaft at the same time as the engagement of the lock-up clutch device, the abrupt fluctuation of the output torque of the engine is transmitted as it is, which causes vibration and noise. . Therefore, a damper device is arranged between the lockup clutch device and the turbine hub. The damper device is locked to the lock-up clutch piston of the lock-up clutch device, one of the two drive plates receiving rotation of the lock-up clutch piston is fixed to the other, and the other is fixed to the turbine hub. And a driven plate, and a spring arranged between the drive plate and the driven plate to absorb a sudden change in the transmission torque. The spring is sandwiched by the two driven plates (see Japanese Patent Application Laid-Open No. 61-252962).

When the transmission torque is rapidly transmitted to the lock-up clutch piston with the engagement of the lock-up clutch device, the spring bends,
While transmitting the transmission torque in the bent state to the input shaft,
Absorbs abrupt changes in transmission torque. Further, between the front cover and the lockup clutch piston, a release side oil chamber for releasing the lockup clutch device,
An engagement-side oil chamber for engaging the lockup clutch device is formed between the lockup clutch piston and the turbine runner. Then, the lock-up clutch device is released by supplying oil to the release side oil chamber,
The lock-up clutch device can be engaged by supplying oil to the engagement-side oil chamber.

[0006]

However, in the above-mentioned conventional fluid transmission device, since the spring is sandwiched between the two driven plates,
The number of parts increases, the weight increases, and the cost increases. Therefore, the outer peripheral edge of the lockup clutch piston is bent inward in the radial direction, the spring is held by the bent portion, and the spring is held from the inner peripheral side by the drive plate connected to the lockup clutch piston. ing. Then, the bent portion is cut out and further bent to form a spring pressing portion, a spring pressing portion is also formed on the drive plate, one end of the spring is pressed by both pressing portions, and the other end of the spring is engaged. There is provided a fluid transmission device that transmits power to the driven plate (Japanese Utility Model Publication No. 63-128359). In this type of fluid transmission, the number of parts is smaller, the cost is lower and the weight is smaller than the conventional fluid transmission which holds the spring by two driven plates.

By the way, in order to further reduce the cost and the weight, it is conceivable to eliminate the drive plate. When the drive plate is eliminated, the spring is pressed only by the pressing portion formed on the lockup clutch piston. However, when the pressing portion is short,
The outer half of the spring, that is, only the outer side in the radial direction of the damper device is pressed from the center of the spring, so that the pressing portion and the end surface of the spring come into contact with each other at one point and press the entire spring. I can't.
As a result, wear at the contact point progresses. Also,
The spring may not bend in an arc along the holding portion, and the spring cannot function effectively. Therefore, if the pressing portion is lengthened, the pressing portion and the end surface of the spring come into contact with each other at two points, and the entire spring can be pressed. However, when the friction material is pressure-bonded to the lockup clutch piston, the friction material and the lockup clutch piston are pressed from both front and back sides. Therefore, the friction material is disposed in the portion where the pressing portion exists. Can not do it. Therefore, it is necessary to avoid the pressing portion and dispose the friction material inward of the pressing portion in the lock-up clutch piston in the radial direction, resulting in a smaller torque capacity.

The present invention solves the above-mentioned problems of the conventional fluid transmission device, can reduce the number of parts, can reduce the weight and the cost, and can sufficiently increase the torque capacity. An object of the present invention is to provide a fluid transmission device capable of performing the above.

[0009]

Therefore, in the fluid transmission device of the present invention, the rotation of the engine is transmitted to the pump impeller through the front cover, and the oil flow generated as the pump impeller rotates. It is designed to rotate the turbine runner. A lock-up clutch piston provided facing the front cover and having a claw portion and a lightening hole formed by punching out the vicinity of the outer peripheral edge, and a driven plate that is rotated integrally with the turbine runner. And one end surface of the spring and the other end surface of the spring that is engaged with the driven plate and the other end surface of the spring.

In addition, on one of the surfaces of the lock-up clutch piston and the front cover that face each other, a first lining that forms a discontinuous friction surface at a radial position corresponding to the lightening hole, and the meat. And a second lining that forms a continuous sealing surface radially inward of the punched hole. In another fluid transmission device of the present invention, the first
And the second lining are integrally formed.

In still another fluid transmission device of the present invention, the claw portion formed on the lock-up clutch piston contacts the spring at a plurality of points.

[0012]

According to the present invention, as described above, in the fluid transmission device, the rotation from the engine is transmitted to the pump impeller through the front cover, and the oil generated by the rotation of the pump impeller is transmitted. The turbine runner is rotated by the flow of.

Then, the lock-up clutch piston, which is provided so as to face the front cover and has a claw portion and a lightening hole formed by punching out the vicinity of the outer peripheral edge, and the turbine runner are rotated integrally. A driven plate, and one end surface of the driven plate is engaged with the claw portion and the other end surface of the driven plate is engaged with the driven plate, and the spring absorbs fluctuations in the transmission torque.

Further, on one of the surfaces of the lock-up clutch piston and the front cover which face each other, a first lining that forms a discontinuous friction surface at a radial position corresponding to the lightening hole, and the meat. And a second lining that forms a continuous sealing surface radially inward of the punched hole. In this case, when the vehicle speed set in advance is obtained after the vehicle has started, the lock-up clutch piston and the front cover are frictionally engaged with each other via the first lining to be engaged with each other. Therefore,
Since the rotation of the engine is transmitted to the input shaft of the speed change mechanism without passing through the fluid transmission device, fuel consumption can be improved.

The rotation transmitted from the front cover via the friction material is transmitted to the input shaft of the transmission mechanism via the spring. In this case, the spring contracts and absorbs fluctuations in the transmission torque when the rotation is transmitted, so it is possible to prevent vibrations, noises, etc. from occurring due to transmission of sudden changes in the output torque of the engine. You can

Since one end surface of the spring is engaged with the claw portion, the lock-up clutch piston and the drive plate can be used together, and it is not necessary to separately provide the drive plate. Therefore, the number of parts can be reduced, the weight can be reduced, and the cost can be reduced. Further, the second
Since the continuous sealing surface can be formed by the lining, the sealability between the engagement-side oil chamber and the release-side oil chamber of the lock-up clutch device can be improved. Further, since the friction surface formed by the first lining can be formed radially outward, the torque capacity of the lockup clutch device can be increased.

In another fluid transmission device of the present invention, the first lining and the second lining are integrally formed. In this case, a notch is formed at a position corresponding to the lightening hole. In still another fluid transmission device of the present invention,
The claw portion formed on the lock-up clutch piston contacts the spring at a plurality of points. In this case, since the force with which the claw portion presses the spring is dispersed, the end surface of the spring is not worn or damaged.

[0018]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sectional view of the essential parts of a fluid transmission device according to a first embodiment of the present invention, and FIG. 2 is a first embodiment of the present invention.
FIG. 7 is an enlarged view of a main part of a lockup clutch piston in the embodiment of FIG. 2A is a front view of a main part of the lockup clutch piston 21, and FIG. 2B is a sectional view of a main part of the lockup clutch piston 21.

In the figure, a torque converter as a fluid transmission device is composed of a pump impeller 11, a turbine runner 12, a stator 13, a lockup clutch device 14 and a damper device 15 which form a torus together with the pump impeller 11. The rotation of the engine transmitted via a crankshaft (not shown) is transmitted to the front cover 16 as a torque converter cover,
Pump impeller 11 fixed to the front cover 16
Is transmitted to When the pump impeller 11 rotates, a flow of oil in the torus rotating around the shaft is generated, and centrifugal force is applied to circulate between the pump impeller 11, the turbine runner 12, and the stator 13.

Further, when the pump impeller 11 has just started to rotate and the rotational speed difference with the turbine runner 12 is large when the vehicle starts, the oil flowing out from the turbine runner 12 hinders the rotation of the pump impeller 11. Flow in the direction. Therefore, a stator 13 is arranged between the pump impeller 11 and the turbine runner 12, and when the rotational speed difference between the two is large, the stator 13 converts the oil flow into a direction that assists the rotation of the pump impeller 11.

When the rotational speed of the turbine runner 12 becomes high and the rotational speed difference between the turbine runner 12 and the pump impeller 11 becomes small, the oil hitting the front side of the blade 31 of the stator 13 hits the back side of the oil. The flow of will be obstructed. Therefore, a one-way clutch 17 that allows the stator 13 to rotate only in a fixed direction is arranged on the inner peripheral side of the stator 13. Therefore, when the oil comes into contact with the back side of the blade 31, the stator 13 naturally rotates, so that the oil can circulate smoothly. Further, the outer race 18 of the one-way clutch 17 has a stator 13
On the other hand, the inner race 19 is fixed to a case of an automatic transmission (not shown).

As described above, the torque converter acts as a torque converter to amplify the torque when the rotational speed difference between the pump impeller 11 and the turbine runner 12 is large, and acts as a fluid coupling when the rotational speed difference becomes small. . Next, the lockup clutch device 14 will be described. The lock-up clutch device 14 includes a lock-up clutch piston 21, a friction material 20 as a first lining that is crimped in the vicinity of the outer peripheral edge of the lock-up clutch piston 21, and the lock-up clutch piston 21 in the radial direction. It is composed of a seal material 22 as a second lining, which is pressed inward from the friction material 20. Since the friction material 20 is arranged to frictionally engage the lock-up clutch piston 21 and the front cover 16, the friction material 20 has a large radial dimension so as to have a sufficient torque capacity. Seal material 2
Since 2 is arranged to secure the sealing property, the size in the radial direction is reduced. Further, by disposing the sealing material 22, not only the sealing performance can be secured, but also the torque capacity can be increased accordingly.

In this embodiment, the friction material 20 is used.
Although the sealing material 22 and the sealing material 22 are both disposed on the surface of the lockup clutch piston 21 facing the front cover 16, they may be disposed on the surface of the front cover 16 facing the lockup clutch piston 21. Then, the lock-up clutch device 1
4 operates by switching the oil supply by a lock-up relay valve (not shown), and the friction material 2 moves when the lock-up clutch piston 21 moves in the axial direction.
0 and the front cover 16 are engaged and disengaged.

Therefore, the release side oil chamber R is provided between the lock-up clutch piston 21 and the front cover 16.
1, an engagement side oil chamber R2 is formed between the lockup clutch piston 21 and the turbine runner 12. Also,
The release-side oil chamber R1 and the engagement-side oil chamber R2 have the sealing material 22.
It is designed to be sealed by. In this case, when the preset vehicle speed is obtained after the vehicle has started, oil is supplied to the engagement-side oil chamber R2 and the lock-up clutch device 14 is engaged. Therefore, the rotation of the engine is transmitted to the input shaft of the transmission mechanism without passing through the torque converter, so that the fuel consumption can be improved. On the other hand, when oil is supplied to the release side oil chamber R1, the lockup clutch device 14 is released.

When the front cover 16 and the lock-up clutch piston 21 are engaged with each other via the friction material 20, the rotation of the crankshaft causes the front cover 16, the lock-up clutch piston 21, the damper device 15 and the turbine hub to rotate. It is directly transmitted to an input shaft (not shown) via 23. Therefore, a spline groove 23a is formed on the inner circumference of the turbine hub 23, and the turbine hub 23 and the input shaft are spline-fitted by the spline groove 23a.

Reference numeral 65 is a thrust bearing arranged between the stator 13 and the turbine hub 23, 66 is a thrust bearing arranged between the stator 13 and the sleeve 67, and 68 is a turbine hub 23 and the front cover. 16 is a thrust bearing disposed between the thrust bearings. The damper device 15 is for absorbing fluctuations in the transmission torque generated when the lockup clutch device 14 is engaged and disengaged, and has claw portions 21a formed at a plurality of locations near the outer peripheral edge of the lockup clutch piston 21. , Is arranged to face the lockup clutch piston 21,
The driven plate 32 is rotated integrally with the turbine runner 12 and a spring 33.

The claw portion 21a is formed by punching out the vicinity of the outer peripheral edge of the lock-up clutch piston 21 and bending the punched piece toward the turbine runner 12 side. The lightening hole 21b is formed. The claw portion 21a extends in the axial direction with the tip end facing the turbine runner 12 side, and when the lockup clutch piston 21 is driven in the positive direction (hereinafter referred to as "forward driving"), or the engine brake is applied. In this case, when the lock-up clutch piston 21 is driven in the reverse direction (hereinafter referred to as "during reverse drive"), one end of the spring 33 is pressed to bend.

Further, the driven plate 32 is formed so as to project toward the turbine runner 12 side in the vicinity of the outer peripheral edge thereof, and a housing portion 32a for housing the spring 33,
And the cut-and-raised portion 32 cut and raised on the lock-up clutch piston 21 side so as to correspond to the end surface of the housing portion 32a.
b. Then, one end surface of the spring 33 is engaged with the claw portion 21a, and the other end surface is engaged with the end surface of the accommodating portion 32a and the cut-and-raised portion 32b. The spring 33 occupies a circumferential length of 85% or more in the circumferential direction of the lock-up clutch piston 21, and constitutes a long stroke damper. In this embodiment, the lock-up clutch piston 21 has two
It is arranged in a place.

Therefore, the rotation transmitted from the front cover 16 via the friction material 20 is once transmitted to the damper device 15 and then transmitted from the damper device 15 to the turbine hub 23. In this case, the spring 33 contracts to absorb the fluctuation of the transmission torque when the rotation is transmitted. As a result, it is possible to prevent the generation of vibration, noise, etc. due to the transmission of a sudden change in the output torque of the engine.

Further, since one end surface of the spring 33 is engaged with the claw portion 21a, the lock-up clutch piston 21 can be used also as the drive plate, and it is not necessary to dispose the drive plate separately. Since the spring 33 is accommodated and held in the accommodating portion 32a of the one driven plate 32, the damper device 15
The number of parts can be reduced. Therefore, the number of parts can be reduced, the weight can be reduced, and the cost can be reduced.

Further, the lock-up clutch piston 21 is punched out so that the pawl portion 21a becomes longer,
When 1a and the end surface of the spring 33 are brought into contact with each other at a plurality of points, the force of pressing the spring 33 by the claw portion 21a is dispersed, so that the end surface of the spring 33 is not worn or broken. The pump impeller 11 and the turbine runner 12 are composed of blades 41 and 42, outer shells 43 and 44 and inner cores 45 and 46, which are arranged on both sides of the blades 41 and 42, respectively. The outer shell 44 of the turbine runner 12 is attached to the turbine hub 23 by the rivets 47.
Connected with.

In this case, since the spring 33 can be arranged at the outermost peripheral portion of the lockup clutch piston 21, it is possible to fully utilize the space formed between the front cover 16 and the torus. Therefore, the diameter of the spring 33 can be set large. Therefore, the spring constant of the spring 33 can be reduced to reduce the natural frequency. In this embodiment, the spring constant of the spring 33 is 130 [kg · m /
rad] is set below.

In this case, the natural frequency of the damper device 15 can be reduced, and the lockup clutch device 14 can be used.
Since the engagement area of can be set to the low speed side accordingly, fuel consumption can be improved. As described above, the driven plate 32 holds the spring 33 by the housing portion 32a, so that only one driven plate 32 needs to be used. Therefore, not only the structure of the torque converter can be simplified, but also the size can be reduced and the weight can be reduced.

By the way, as shown in FIG.
Since 1a is formed at a plurality of positions in the vicinity of the outer peripheral edge of the lockup clutch piston 21, the friction material 20 disposed in the vicinity of the outer peripheral edge of the lockup clutch piston 21 is only the portion corresponding to the lightening hole 21b. Cannot be placed. Therefore, the friction material 20 has a fan shape extending in the circumferential direction between the lightening holes 21b.
A discontinuous friction surface is formed with the front cover 16.

On the other hand, the sealing material 22 is the lightening hole 2 in the radial direction of the lockup clutch piston 21.
Since the lock-up clutch piston 21 is disposed inward of 1b, the lock-up clutch piston 21 can be formed into a continuous ring shape over the entire circumference. Therefore, since the sealing material 22 forms a continuous sealing surface with the front cover 16, sufficient sealing performance can be ensured.

The friction material 20 and the seal material 22 may be formed integrally by adjoining each other in the radial direction of the lockup clutch piston 21. Next, a second embodiment in which the friction material 20 and the sealing material 22 are integrally formed will be described. FIG. 3 is an enlarged view of a main part of a lockup clutch piston according to the second embodiment of the present invention.
Note that (a) of the figure shows the lockup clutch piston 21.
FIG. 3B is a front view of the main part of FIG.

In this case, a continuous friction / sealing material 71 is arranged near the outer peripheral edge of the lockup clutch piston 21. Also, the lockup clutch piston 21
The lightening holes 21b are formed by forming the claw portions 21a at a plurality of positions in the vicinity of the outer peripheral edge of the. Therefore,
A cutout 71a is formed in the friction / sealing material 71 at a position corresponding to the lightening hole 21b.

Further, the friction material 20 (FIG. 1) and the sealing material 22 may be arranged on the front cover 16.
In that case, both the friction material 20 and the sealing material 22 can be formed into a continuous ring shape. Further, the friction / sealing material 71 can be arranged on the front cover 16,
In that case, a continuous ring can be formed. It should be noted that the present invention is not limited to the above-described embodiments, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

[Brief description of drawings]

FIG. 1 is a sectional view of essential parts of a fluid transmission device according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of a lockup clutch piston according to the first embodiment of the present invention.

FIG. 3 is an enlarged view of a main part of a lockup clutch piston according to a second embodiment of the present invention.

[Explanation of symbols]

 11 Pump Impeller 12 Turbine Runner 16 Front Cover 20 Friction Material 21 Lockup Clutch Piston 21a Claw 21b Lightening Hole 22 Sealing Material 32 Driven Plate 33 Spring

Claims (3)

[Claims] 1. A fluid transmission device for transmitting a rotation from an engine to a pump impeller through a front cover, and rotating a turbine runner by a flow of oil generated by the rotation of the pump impeller, which opposes the front cover. And a lock-up clutch piston provided with a claw portion and a lightening hole formed by punching in the vicinity of the outer peripheral edge, a driven plate rotated integrally with the turbine runner, and one end surface of the driven plate. The other end of the claw portion is locked to the driven plate and absorbs the fluctuation of the transmission torque. One of the surfaces of the lock-up clutch piston and the front cover facing each other corresponds to the lightening hole. The first lining that forms a discontinuous friction surface at a radial position that is A second lining that forms a continuous sealing surface inwardly. 2. The fluid transmission device according to claim 1, wherein the first lining and the second lining are integrally formed. 3. The fluid transmission device according to claim 1, wherein the pawl portion formed on the lock-up clutch piston contacts the spring at a plurality of points.