JPH066782U - Torsional vibration damping device and torque converter lockup device - Google Patents

Abstract

(57) [Summary] [Purpose] To maintain the desired viscous damping effect. [Structure] A viscous damper mechanism 15 of a power transmission system disposed between a driven plate 14 and a first drive plate 12 and a second drive plate 13 includes an annular case 1
7 and a slider 19. The annular case 17
First drive plate 12 and second drive plate 1
3 to form an annular liquid chamber 18 filled with a viscous material. The slider 19 is connected to the driven plate 14 and is movably arranged in the annular liquid chamber 18 in the circumferential direction with a predetermined gap from the inner wall of the annular case 17, and has a thermal expansion coefficient larger than that of the annular case 17. Have

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a torsional vibration damping device and a torque converter lockup device.

[0002]

[Prior art]

 A torque converter is a device that has three types of impellers (impeller, turbine, stator) inside and that transmits power by hydraulic oil inside. The impeller is fixed to the front cover connected to the input side member, and the turbine driven by the hydraulic oil flowing from the impeller is connected to the output side member.

In some torque converters, a lockup device is arranged between the turbine and the front cover. The lockup device is for directly transmitting the rotational force from the front cover to the output side member. In such a lockup device, an elastic member such as a torsion spring is used to absorb the torsional vibration. However, the torsion spring cannot cope with low-frequency vibrations due to acceleration / deceleration during lockup operation, which causes noise.

In order to solve such a problem, a lockup device provided with a viscous damping mechanism that operates in parallel and an elastic coupling device is shown in Japanese Utility Model Laid-Open No. 61-123258. The torsional vibration damping device of this lockup device is mainly composed of a cylindrical portion provided on the input side member and a second cylindrical portion connected to the output side member, and an annular portion is provided between the two. A liquid chamber is provided. Partition plates extending toward each other are alternately formed on the first cylindrical part and the second cylindrical part, and a predetermined gap is formed between the tip part of one partition plate and the other cylindrical part. There is. When the two cylindrical parts are twisted with each other by the torsional vibration, the liquid flows through the gap and a viscous damping force is generated.

However, in the above-mentioned conventional configuration, the precision of the gap formed between the partition plate of one cylindrical portion and the other cylindrical portion is inevitably low. That is, when mounting both the cylindrical parts on the input side member and the output side member respectively, the size of each gap will be different due to processing error and assembly error. Further, if the gap is narrowed, when viscous friction is repeated and the temperature of the liquid rises, the viscosity of the liquid decreases, so the viscous damping force decreases, and the desired damping effect cannot be obtained.

An object of the present invention is to maintain the desired viscous damping effect.

[0007]

[Means for Solving the Problems]

 The torsional vibration damping device according to the first invention is arranged between an input side member and an output side member and is used in a power transmission system. This device includes an annular case and a slider. The annular case is connected to one of the input side member and the output side member, and forms a liquid chamber filled with a liquid therein. The slider is connected to the other of the input side member and the output side member, and is arranged so as to be movable in the circumferential direction in the liquid chamber through a predetermined gap with the inner wall of the annular case. The slider has a coefficient of thermal expansion larger than that of the annular case.

The lockup device according to the second invention is used in a torque converter including a front cover connected to an input side member and a turbine connected to an output side member. The lockup device includes a disc-shaped piston, a torsional vibration damping device, and an elastic coupling device. The piston is arranged between the turbine front cover and the turbine so as to be movable in the axial direction, and can be pressed against the front cover. The torsional vibration damping device includes an annular case that is connected to one of a piston and an output side member and has a liquid chamber formed therein, and a liquid chamber that is movably arranged in a circumferential direction in the liquid chamber of the annular case. A slider having a predetermined gap between the slider and the inner wall, and a connecting member for connecting the slider to the piston and the other of the output side members. The elastic connecting device connects the piston and the output member in parallel with the torsional vibration damping device.

[0009]

[Action]

 In the torsional vibration damping device according to the first aspect, when the torque fluctuation is transmitted from the input side member, the annular case and the slider are twisted in the rotational direction with respect to each other. Then, the liquid flows through the gap formed between the inner wall of the annular case and the slider. At this time, viscous damping is performed by the frictional resistance generated in the gap, and as a result, the torsional vibration is absorbed.

When the temperature of the liquid rises due to the frictional resistance, the slider having a coefficient of thermal expansion larger than that of the annular case thermally expands more than that of the annular case, narrowing the gap between the slider and the inner wall of the annular case. Therefore, even if the viscosity of the liquid decreases due to the temperature rise, the desired viscous damping effect can be maintained. In the lockup device for a torque converter according to the second aspect of the present invention, when the disc-shaped piston moves axially and is pressed against the front cover, the torque from the input side member causes the disc-shaped piston and the screw to rotate from the front cover. It is transmitted to the output side member via the torsional vibration damping device and the elastic coupling device.

When the torsional vibration is transmitted from the input side member, the torsional vibration damping device and the elastic coupling device work in parallel to effectively absorb the torsional vibration. Here, when the torsional vibration is transmitted, the annular case, the slider, and the connecting member are twisted with each other. At this time, the liquid passes through the gap between the slider and the inner wall of the liquid chamber, and a viscous damping force is generated.

Here, since the slider can be formed with high precision so as to have a predetermined gap in accordance with the size of the annular case, the precision of the gap becomes high, and the desired viscous damping effect can be maintained.

[0013]

【Example】

 FIG. 1 shows a torque converter 1 according to an embodiment of the present invention. In FIG. 1, O-O is the rotation center line of the torque converter 1. The torque converter 1 mainly includes a torus unit 2 and a lockup device 3. The front cover 4 that can be connected to the engine side (not shown) has a cylindrical protrusion 4a on the outer side in the circumferential direction, and this protrusion 4a is fixed to the impeller shell 5a of the impeller (pump) 5. The front cover 4 and the impeller shell 5a together form a hydraulic oil chamber filled with hydraulic oil.

The torus portion 2 is mainly composed of an impeller (pump) 5, a turbine 6, and a stator 7. The inner peripheral end of the impeller shell 5a of the impeller 5 is fixed to the impeller hub 5c. A plurality of impeller blades 5b are fixed inside the impeller shell 5a. A turbine 6 is arranged at a position facing the impeller 5. The turbine 6 is composed of a turbine shell 6a and a plurality of turbine blades 6b fixed to the turbine shell 6a. The inner peripheral end portion of the turbine shell 6a is fixed to the flange portion 8a of the turbine hub 8 with rivets 9. The turbine hub 8 has a spline 8b that engages with an input shaft (not shown) of the transmission on the inner peripheral portion thereof. The stator hub is provided between the inner peripheral portion of the impeller 5 and the inner peripheral portion of the turbine 6. 7 are arranged. The stator 7 adjusts the direction of the hydraulic oil returned from the turbine 6 to the impeller 5, and is composed of an annular stator carrier 7a and a plurality of stator blades 7b formed on the outer peripheral surface of the stator carrier 7a. Has been done. The stator carrier 7a is connected to the inner race 10 via a one-way clutch mechanism. The inner race 10 is connected to a fixed shaft (not shown) extending from the housing side (right side in the drawing).

The lockup device 3 is arranged between the front cover 4 and the turbine 6. The lock-up device 3 is mainly composed of a disc-shaped piston 11, a viscous damper mechanism 15 and an elastic connecting portion 16 that operate in parallel. The piston 11 has its radially inner peripheral end slidably supported on the outer peripheral surface of the turbine hub 8 in the axial direction and the circumferential direction. An annular friction member 11a is bonded to the outer peripheral portion of the piston 11 in the radial direction on the surface facing the friction surface 4b of the front cover 4. The piston 11 has a cylindrical end wall 11b extending axially rearward (rightward in FIG. 1) at the outer peripheral side end. The end wall 11b has a plurality of notches extending in the circumferential direction.

Disc-shaped first and second drive plates 12 and 13 and a driven plate 14 are provided as members constituting the viscous damper mechanism 15 and the elastic connecting portion 16. As shown in FIGS. 2 and 3, the first drive plate 12 and the second drive plate 13 have protrusions 12a and 13a that protrude outwardly at their radially outer ends and abut against each other. The protrusions 12a and 13a are connected by a rivet 20. Further, the protrusions 12a and 13a are engaged with notches formed in the end wall 11b of the piston 11 (FIG. 1), whereby the piston 11 is engaged with both drive plates 12 and 13 in the circumferential direction. It is possible to move in the axial direction while being stopped and be connected to the front cover 4.

The first drive plate 12 and the second drive plate 13 have accommodating portions 12b and 13b that extend in the circumferential direction and project outward in the axial direction. The accommodating portion 13b is divided by a notch 13c formed in the drive plate 13, and the notch 13c has a notch insert portion 13d extending radially inward from the protrusion 13a of the drive plate 13. There is.

A metal arc-shaped case 17 is fixed in the space formed by the accommodating portions 12b and 13b. Both ends of the arc-shaped case 17 are in contact with the notch inner insertion portion 13d. The annular liquid chamber 18 of the arc-shaped case 17 is filled and commonly used with the hydraulic oil used in the torus portion 2. Further, a box-shaped slider 19 made of resin is arranged in the liquid chamber 18. The outer peripheral wall and the inner peripheral wall of the box-shaped slider 19 have an arc shape similar to the outer peripheral wall and the inner peripheral wall of the arc-shaped case 17, and are movable in the circumferential direction in the liquid chamber 18. The slider 19 divides the liquid chamber 18 into a compartment 18a and a compartment 18b.

A slit 17 a extending in the circumferential direction is formed on the inner wall of the arc-shaped case 17 in the radial direction, and a protrusion 14 a formed on the outer side of the driven plate 14 in the radial direction is formed in the slit 17 a. Has been inserted. Moreover, the tip of the protruding portion 14a is arranged in the slider 19 so as to rotate integrally with the slider 19. A small gap is secured between the slider 19 and the inner wall of the arc-shaped case 17. Here, the thermal expansion coefficient of the slider 19 made of resin is larger than that of the arc-shaped case 17 made of metal. Therefore, when the temperature of the hydraulic oil rises, the slider 19 expands, and the gap between the slider 19 and the arc-shaped case 17 becomes smaller. Although the viscosity of the hydraulic oil decreases as the temperature rises, the decrease in viscosity and the narrowing of the gap are set to be proportional to each other, whereby the damping effect is maintained.

Since the gap is determined by adjusting the size of the slider 19 with respect to the arc-shaped case 17, the precision of the gap is high. Therefore, the desired damping effect is maintained. That is, in this embodiment, the dimension of the gap between the arc-shaped case 17 and the slider 19 can be secured with high accuracy simply by controlling the processing accuracy, and compared with the conventional device, the accurate characteristics can be reproduced with simple processing. Sex is obtained. Moreover, a sufficiently high viscous damping force can be obtained even if the relatively low-viscosity hydraulic oil in the torus portion 2 is shared.

The radially inner end of the driven plate 14 is integrally connected to the flange portion 8 a of the turbine hub 8 by a plurality of rivets 9. Six window holes 14b extending in the circumferential direction are formed in the intermediate portion of the driven plate 14 in the radial direction. Four long first torsion springs 20a and two short second torsion springs 20b are arranged in the window hole 14b. The second torsion spring 20b is arranged in the window hole 12b with a gap in the circumferential direction. Axial cut-and-raised parts 12e and 13e are formed in the radial middle part of the first drive plate 12 and the second drive plate 13 and at a part corresponding to the window hole 14b. The first drive plate 12 and the second drive plate 13 are fixed to each other by a plurality of rivets 21. As shown in FIG. 2, the rivet 21 is inserted into a circular elongated hole 14c formed in the driven plate 14 and is movable in a predetermined range in the circumferential direction.

Next, the operation of the above embodiment will be described. When an engine (not shown) rotates, torque is input to the front cover 4. Then, the impeller 5 rotates together with the front cover 4. This rotation is transmitted to the turbine 6 via hydraulic oil. The flow of hydraulic oil returning from the turbine 6 to the impeller 5 is adjusted by the stator 7. Then, the rotation of the turbine 6 is transmitted to an input shaft (not shown) of the transmission via the turbine hub 8.

When the input shaft (not shown) of the transmission becomes a constant rotation, the hydraulic pressure of the hydraulic oil chamber in the torque converter 1 is increased and the hydraulic pressure between the front cover 4 and the piston 11 is released. As a result, the piston 11 is pressed against the front cover 4. When the friction member 11a of the piston 11 is brought into pressure contact with the friction surface 4b of the front cover 4, the rotation of the front cover 4 is mechanically transmitted to the turbine hub 8 not through the torus portion 2 but through the lockup device 3.

During the above lock-up operation (when the engine is rotating at high speed), the torsional vibration is transmitted from the engine side to the torque converter 1 by the acceleration / deceleration operation or the like. When this torsional vibration occurs, the viscous damper mechanism 15 and the elastic connecting portion 16 operate in parallel between the first drive plate 12 and the second drive plate 13, and the driven plate 14 to twist the same. Damps vibration.

While the lockup device 3 is operating, the viscous damper mechanism 15 operates against the torsional vibration, so that the temperature of the hydraulic oil in the liquid chamber 18 rises. As the temperature rises, the slider 19 expands stronger than the arc-shaped case 17, and the gap between the slider 19 and the inner wall of the arc-shaped case 17 becomes narrower. Therefore, the desired viscous damping effect is maintained even though the viscosity of the hydraulic oil decreases due to the temperature rise.

[0026]

[Effect of device]

 In the torsional vibration damping device according to the first invention, when the temperature of the liquid rises due to frictional resistance, the slider having a coefficient of thermal expansion larger than that of the annular case thermally expands more than that of the annular case, and the slider and the annular case are Since the gap with the inner wall is narrowed, the desired viscous damping effect can be maintained even if the viscosity of the liquid decreases due to the temperature rise.

In the lockup device for a torque converter according to the second aspect of the present invention, since the slider that produces the viscous damping effect can be accurately formed so as to have a predetermined gap according to the size of the annular case, the precision of the gap can be improved. Is higher and the desired viscous damping effect can be maintained.

[Brief description of drawings]

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

FIG. 2 is a front view of the lockup device.

FIG. 3 is a sectional view taken along line III-III of FIG.

[Explanation of symbols]

 1 Torque Converter 3 Lockup Device 4 Front Cover 6 Turbine 11 Piston 12 First Drive Plate 13 Second Drive Plate 14 Driven Plate 15 Viscous Damper Mechanism 16 Elastic Connection Part 17 Arc Case 18 Liquid Chamber 19 Slider

Claims (2)

[Scope of utility model registration request] 1. A torsional vibration damping device for a power transmission system arranged between an input side member and an output side member, wherein the device is connected to one of the input side member and the output side member and has a liquid inside. And an annular case that forms a liquid chamber filled with, and is connected to the other of the input side member and the output side member, and is movable in the circumferential direction in the liquid chamber through a predetermined gap with the inner wall of the annular case. And a slider having a coefficient of thermal expansion larger than that of the annular case, the torsion vibration damping device being provided. 2. A lockup device for a torque converter including a front cover connected to an input side member and a turbine connected to an output side member, wherein the lockup device moves axially between the turbine and the front cover. A disc-shaped piston that is freely arranged and can be pressed against the front cover, an annular case that is connected to any one of the piston and the output side member and has a liquid chamber formed therein, and the liquid of the annular case. A slider that is movably arranged in the chamber in the circumferential direction and has a predetermined gap between the slider and the inner wall of the liquid chamber; and a connecting member that connects the slider to the piston and the other of the output side members. A torsional vibration damping device; and an elastic coupling device that is arranged in parallel with the torsional vibration damping device and that couples the piston and the output side member. Lockup device for converter.