JPH0262472A - Torque converter with lock up clutch - Google Patents

Abstract

PURPOSE:To accurately and quickly control the oil pressure in an oil pressure chamber and enable the accurate setting of the operating characteristic of a clutch by mutually cutting off a hydraulic oil chamber and the oil pressure chamber in both sides of a piston. CONSTITUTION:At the time of the connection cutoff action of a clutch, a piston 11 integrally comprises tubelous parts 41, 42 at the inner peripheral and the outer peripheral of it. The inner peripheral surface of the tubelous part 41 is slidably engaged with the outer peripheral surface of a turbine hub 17 through a seal 43, and the outer peripheral surface of the tubelous part 42 is slidably engaged with the inner peripheral surface of a peripheral wall 5 through a seal 45. At this stage, since an oil pressure chamber 22 is cut off to a hydraulic oil chamber 21, the leakage of the oil pressure of the oil pressure chamber 22 to the hydraulic oil chamber 21 side can be effectively prevented. Consequently, by changing the oil pressure supplied from a control oil passage 35, the oil pressure of the oil pressure chamber 22 to the oil pressure of the hydraulic oil chamber 21 can be adjusted accurately and quickly, and the action of the piston 11, that is, the connection cutoff action of the clutch can be controlled accurately and quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a torque converter with a lock-up clutch used in automobiles and the like.

[Prior Art] A lock-up clutch generally used in a torque converter is composed of a piston driven by hydraulic pressure and a clutch disc equipped with a friction facing.
By pressing the friction facing against a front cover or the like in response to the movement of the piston, the input section and output section (for example, a turbine hub) of the torque converter are directly connected via the clutch disk.

In some conventional lock-up clutches, the piston and the input member of the clutch disk are made of the same member. In such a structure, the inner periphery of the piston (input member of the clutch disc) is slidably fitted to the outer periphery of the turbine hub, etc. via a seal, and the outer periphery is fitted to the cylindrical peripheral wall of the front cover. A gap separates them.

[Problems to be Solved by the Invention] However, in the structure where there is a gap between the outer periphery of the piston and the cylindrical peripheral wall of the front cover as described above, the hydraulic chamber for the lock-up clutch (the chamber between the piston and the front cover) and the hydraulic oil chamber on the opposite side (the space between the piston and the turbine) communicate through the gap, so the relative oil pressure between the hydraulic chamber and the hydraulic oil chamber can be accurately controlled. As a result, it may be difficult to operate the lock-up clutch accurately depending on the driving condition of the vehicle.

The present invention seeks to provide a structure that solves the above problems.

[Means for Solving the Problems] The present invention provides a torque converter main body that connects an impeller, a turbine, and a stator, a front cover that is connected to the impeller and constitutes an input section of the torque converter, and a structure that connects the front cover and the turbine. an output member that is connected to the turbine; an input member that can be pressed against the radially extending inner surface of the front cover; and the input member and the output member are connected in the circumferential direction. The target is a torque converter with a lock-up clutch equipped with a damper spring.

In order to solve the above problems, the present invention provides such a torque converter in which the outer periphery of the input member is slidably fitted to the inner periphery of the cylindrical peripheral wall of the front cover via a seal, and the inner periphery of the input member is slidably fitted to the inner periphery of the cylindrical peripheral wall of the front cover. The circumference is slidably connected to the hub of the turbine via a seal, thereby connecting the hydraulic chamber formed between the input member and the front cover to the hydraulic oil chamber formed between the input member and the turbine. It is characterized by a hydraulic control oil passage connected to the hydraulic chamber.

C action] Above (according to the R construction, the hydraulic chamber is isolated from the hydraulic oil chamber on both its inner and outer circumferential sides, so the relative oil pressure between the hydraulic chamber and the hydraulic oil chamber can be accurately and quickly adjusted. Therefore, the engagement and disengagement operations of the lock-up clutch can be controlled accurately and quickly.

[Embodiment] In FIG. 1, a front cover 1 is a member constituting the input section of a torque converter, and is connected to the output section of the engine shown in the figure. Front cover 1 is output shaft 2
(only the centerline is shown) an end wall 3 extending in a generally radial direction;
It integrally has a peripheral wall 5 extending from the outer periphery of the end wall 3 toward the torque converter main body 4 side. As is well known, the torque converter main body 4 includes an impeller 6, a turbine 7, and a stator 8, and the tip of the peripheral wall 5 is fixed to the shell of the impeller 6.

A clutch disc 10 is arranged between the end wall 3 and the turbine 7. The clutch disc 10 includes a piston 11, an output plate 12, and a damper spring 13. The piston 11 also serves as an input member of the clutch disc, and is composed of an annular plate extending generally in the radial direction of the torque converter. A friction facing 15 (input portion) is attached to the outer periphery of the surface of the piston 11 on the end wall 3 side. The output plate 12 has the piston 11 and the turbine 7
The inner peripheral portion is fixed to the turbine hub 17 by a clutch disk 10. The damper spring 13 is arranged adjacent to the outer periphery of the piston 11 and the output plate 12, and connects them in the circumferential direction.

In order to connect the piston 11 and the damper spring 13, a connecting member 19 is fixed to the outer circumference of the piston 11 with a rivet 18. The connecting member 19 is a plate-shaped portion having a plurality of bent claws, and holds the damper spring 13 from the outside and inside in the radial direction, and engages with the damper spring 13 in the circumferential direction. The output plate 12 is also provided with claws on its outer periphery that engage with the damper spring 13 in the circumferential direction. One of the connecting members and the output plate 12 are connected to the damper spring 13 via these claws.

The interior of the torque converter can be divided into three types of chambers: an internal chamber 20, a hydraulic oil chamber 21, and a hydraulic chamber 22.

The internal chamber 20 contains the impeller 6 and the shell 25 of the turbine 7.
26, and rotational force is transmitted from the impeller 6 to the turbine 7 via the hydraulic oil that fills the space. In order to supply and discharge hydraulic oil to and from the internal chamber 20, an inlet oil passage 31 and an outlet oil passage 32 are formed on both sides of a one-way clutch 30 built into the inner periphery of the stator 8. The hydraulic oil chamber 21 contains the piston 11 and the turbine shell 26
It is the space formed between

The hydraulic chamber 22 is a space formed between the piston 11 and the end wall 3, and in order to control the hydraulic pressure in the hydraulic chamber 22, a control oil passage 35 communicating with the inner circumference of the hydraulic chamber 22 is connected to the turbine hub 17.
and the inner peripheral portion of the end wall 3. This control oil passage 35 is connected to an external hydraulic control mechanism via an internal oil passage of the output shaft 2 or the like.

According to the above structure, by controlling the hydraulic pressure in the hydraulic chamber 22 via the control oil passage 35, that is, by increasing or decreasing the hydraulic pressure in the hydraulic chamber 22 relative to the hydraulic pressure in the hydraulic oil chamber 21,
The connection/disconnection operation of the clutch is controlled as follows.

When the hydraulic pressure in the hydraulic chamber 22 is relatively increased, the piston 11 is pushed by the hydraulic pressure in the hydraulic chamber 22, so the friction facing 15 separates from the end wall 3, and the clutch is disengaged. When the oil pressure in the hydraulic chamber 22 is relatively lowered, the piston 11 is pushed toward the end wall 3 by the oil pressure in the hydraulic oil chamber 21, and the friction facing 15 comes into pressure contact with the end wall 3. Therefore, the rotational force of the end wall 3 is transmitted from the friction facing 15 to the piston 11,
1 connecting member from piston 11, damper spring 1
3. It is transmitted to the turbine hub 17 via the output plate 12, and from the turbine hub 17 to the output shaft 2.

In the clutch connection/disconnection operation described above, its operating characteristics are precisely controlled as follows.

That is, the piston 11 has cylindrical portions 41 on its inner and outer peripheries.
and 42 are integrated. The inner circumferential surface of the cylindrical portion 41 is slidably fitted to the outer circumferential surface of the turbine hub 17 via a seal 43 . The cylindrical portion 42 has a seal 45 on its outer peripheral surface.
It is slidably fitted to the inner circumferential surface of the peripheral wall 5 via. The cylindrical portion 42 is brought into contact with the inner periphery of the peripheral wall 5 only at the seal 45, and the cylindrical portion 42 and the peripheral wall 5 are brought into contact with each other at a portion other than the seal 45.
It is preferable to form a very small gap between them.

In this structure, since the hydraulic chamber 22 is isolated from the working chamber 21, the hydraulic pressure in the hydraulic chamber 22 can be effectively prevented from leaking to the working oil chamber 21 side.

Therefore, by simply changing the oil pressure supplied from the control oil passage 35, the oil pressure in the oil pressure chamber 22 relative to the oil pressure in the hydraulic oil chamber 21 can be adjusted accurately and quickly, and the operation of the piston 11, that is, the connection and disconnection operation of the clutch can be accurately and quickly adjusted. It can be controlled quickly.

Further, when the hydraulic chamber 22 is completely isolated from the hydraulic oil chamber 21, the hydraulic oil in the hydraulic chamber 22 has no place to escape other than the control oil passage 35. Therefore, in the clutch connecting operation, the piston 1
1 moves toward the end wall 3, the piston 11 moves into the hydraulic chamber 22.
Since the hydraulic oil inside is compressed, it may be difficult to move the piston 11 lightly and quickly toward the end wall 3 side.

In order to eliminate such problems, a check valve 50 is provided at the radially intermediate portion of the piston 11.

The check valve 50 has a hole 51 provided in the piston 11,
A leaf spring 52 that can close the opening of the hole 51 on the hydraulic oil chamber 21 side.
and a rivet 53 for fixing the leaf spring 52 to the piston 11. The leaf spring 52 is composed of, for example, a band-shaped leaf spring extending in the radial direction, and the inner part in the radial direction is fixed to the piston 11 with a rivet 53, and the outer part can close the hole 51. .

When the oil pressure in the hydraulic chamber 22 becomes relatively higher than the oil pressure in the hydraulic oil chamber 21, the leaf spring 52 is elastically deformed to open the hole 51. Therefore, when the piston 11 moves in the connecting direction and starts compressing the hydraulic oil in the hydraulic chamber 22, the hydraulic oil in the hydraulic chamber 22 flows from the hole 51 to the hydraulic oil chamber 21, and as a result, the piston 11 moves into the hydraulic chamber 22. It can be moved easily and quickly in the direction of clutch engagement without compressing the hydraulic oil inside.

Further, in the above structure, the hydraulic oil in the hydraulic oil chamber 21 cannot flow to the hydraulic chamber 22 side. Further, the hydraulic oil chamber 21 communicates with the internal chamber 20 only through a narrow gap between the impeller 6 and the outer periphery of the turbine 7. Therefore, if hydraulic oil chamber 2
1 is communicated with the internal chamber 20 only through the gap, the hydraulic pressure of the hydraulic oil in the hydraulic oil chamber 21 becomes relatively high due to centrifugal force, and therefore the turbine 7 is connected to the internal chamber 20 through the gap.
It is pushed toward the impeller 6 by the hydraulic pressure inside. When the pressing force increases, for example, the surface pressure at the contact portion between the turbine hub 17 and the one-way clutch 30 increases, and there is a possibility that wear may occur in the contact portion.

In order to prevent such defects, holes are formed in the inner peripheral part of the turbine shell 26 of the turbine 7, more precisely in the part radially inward of the blades of the turbine 7 and radially outward of the turbine hub 17. 55 is provided so that the hydraulic pressure in the hydraulic oil chamber 21 is released to the internal chamber 20 through the hole 55.

With this structure, the oil pressure in the hydraulic oil chamber 21 does not rise significantly compared to the oil pressure in the internal chamber 20, and the one-way clutch 30
Thus, an increase in surface pressure of the turbine hub 17 can be prevented.

[Effects of the Invention] As explained above, according to the present invention, since the hydraulic fluid chamber 21 and the hydraulic chamber 22 on both sides of the piston 11 are isolated from each other,
It becomes possible to accurately and quickly control the oil pressure in the hydraulic chamber 22, and it becomes possible to accurately set the operating characteristics of the clutch.

C. Another Embodiment Although the above-described check valve 50 uses a leaf spring 52, a structure as shown in FIG. 2 may be adopted instead of that structure. In the structure shown in FIG. 2, the portion of the hole 51 provided in the piston 11 on the side of the hydraulic oil chamber 21 widens in a tapered shape, and the ball 60 is seated on the tapered inner peripheral surface. When the oil pressure in the hydraulic chamber 22 becomes relatively high, the ball 60 separates from the tapered inner peripheral surface of the hole 51 and moves into both chambers 22.
Connect 21. In order to prevent the ball 60 from falling off, a falling-off prevention member such as a washer 61 is attached to the inner periphery of the large diameter end of the hole 51.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of an embodiment of the present invention, and FIG. 2 is a partial sectional view showing another embodiment of the check valve. DESCRIPTION OF SYMBOLS 1... Front cover, 4... Torque converter main body, 5... Front cover peripheral wall, 6... Impeller 7... Turbine, 8... Stator, 10... Clutch disk, 11...・Piston, 12... Output plate, 13... Damper spring, 17... Turbine hub, 21... Hydraulic oil chamber, 22... Hydraulic chamber,
35...Hydraulic control oil path, 43...Seal, 45...
・Seal Figure 1 2 No.

Claims (1)

[Claims] It includes a torque converter main body having an impeller, a turbine, and a stator, a front cover that is connected to the impeller and constitutes an input section of the torque converter, and a clutch disc that is disposed between the front cover and the turbine. In a torque converter with a lock-up clutch, the torque converter includes an output member connected to a turbine, an input member that can be pressed into contact with an inner surface extending in the radial direction of a front cover, and a damper spring that connects the input member and the output member in the circumferential direction. , the outer periphery of the input member is slidably fitted to the inner periphery of the cylindrical peripheral wall of the front cover via a seal, the inner periphery of the input member is slidably connected to the hub of the turbine via the seal, and The hydraulic chamber formed between the input member and the front cover is isolated from the hydraulic oil chamber formed between the input member and the turbine, and a hydraulic control oil passage is connected to the hydraulic chamber. Torque converter with lock-up clutch.