JPH05141447A - Automatic transmission - Google Patents

Abstract

PURPOSE:To provide an automatic transmission which can stabilize the operation of a centrifugal cancellation piston and allows this piston to be designed smaller and lighter. CONSTITUTION:A clutch pack 7 having a centrifugal cancellation piston 8 is supported rotatably through bearings 6a and 6b by a stationary member 4 fixed in a transmission case. A lubrication circuit 11 which supplies the centrifugal cancellation piston 8 with lubricating oil is formed in the stationary member 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic transmission, and more particularly to an automatic transmission having a centrifugal cancel piston.

[0002]

2. Description of the Related Art Conventionally, as an automatic transmission having a centrifugal cancel piston, for example, one disclosed in Japanese Patent Laid-Open No. 2-3706 is known. That is, in this document, a centrifugal cancel piston is provided in a clutch pack that engages and disengages a multi-plate clutch so that the clutch pack does not move to the engagement side by centrifugal hydraulic pressure when the engagement is released. ing.

[0003]

However, according to this prior art, since the lubrication of the centrifugal cancel piston is guided from a part of the lubrication circuit that lubricates the other parts, a change in the number of revolutions and the lubricating oil. Is easily affected by the viscosity of, and the amount of lubricating oil becomes unstable, making the centrifugal cancel piston effect unstable.

Further, the centrifugal cancel piston is formed to have a large diameter in order to obtain a stable operation as much as possible from the above, which causes an increase in size and an increase in weight.

The present invention has been made in view of the above problems, and provides an automatic transmission capable of stabilizing the operation of a centrifugal cancel piston and at the same time reducing the size and weight of the centrifugal cancel piston. The purpose is to

[0006]

SUMMARY OF THE INVENTION The present invention achieves the above object by independently supplying lubricating oil to a centrifugal cancel piston.

That is, in the automatic transmission according to the present invention, a clutch pack having a centrifugal cancel piston is rotatably supported by a case or a fixing member fixed to the case via a bearing, and the case or the fixing member is provided with the clutch pack. A lubricating circuit for supplying lubricating oil to the centrifugal cancel piston is formed.

[0008]

When the lubricant is supplied, the lubricating oil is directly supplied from the lubrication circuit to the centrifugal cancel piston. With this, the amount of lubricating oil to the centrifugal cancel piston is stabilized and ensured, and the operation of the centrifugal cancel piston is ensured.
It is possible to eliminate the drift-on ball and reduce the diameter of the centrifugal cancel piston.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing a main part of an automatic transmission according to an embodiment, and in the drawing, 1 indicates an input shaft. Rotational force is transmitted from an engine output shaft (not shown) to the input shaft 1 through a torque converter. The rotational force of the input shaft 1 is changed by a transmission mechanism having a planetary gear mechanism 2 and the like, and then output. It is transmitted from the gear 3 to a differential gear device (not shown) provided adjacently.

As shown in FIG. 1, the planetary gear mechanism 2 includes a sun gear 2a connected to the input shaft 1 by a spline 1a, an internal gear 2b provided outside the sun gear 2a, and the sun gear. 2a and an internal gear 2b, and a carrier 2c that supports a pinion gear (not shown) that meshes with both gears at the same time. The carrier 2c is connected to the outer peripheral surface of the output shaft 3a having the output gear 3 by a spline 3b. A bearing 3c is provided between the input shaft 1 and the output shaft 3a.

The output shaft 3a is rotatably supported by a fixed member 4 fixed to a transmission case (not shown) via bearings 3d, 3e, 3f and 3g.

By the way, the planetary gear mechanism includes the sun gear 2a, the internal gear 2b and the carrier 2c.
By fixing or driving each element,
The rotation speed of the output shaft 3a relative to the rotation speed of the input shaft 1 is changed.

The clutch 5 is one of the means for fixing and driving the above, and is provided between the internal gear 2b and the drum 6 installed on the outer periphery thereof. That is, the drum 6 is mounted on the fixed member 4 by bearings 6a,
It is rotatably provided via 6b. The drive plate 6d is axially movably coupled to the spline 6c formed on the inner circumference of the drum 6, and
Spline 2 formed on the outer periphery of internal gear 2b
Driven plates 6e are alternately arranged at d and are connected to driven plates 6e so as to be movable in the axial direction. A clutch pack 7 for engaging and disengaging the plates 6d and 6e by receiving hydraulic pressure is provided on the inner circumference of the drum 6, and the clutch pack 7 is engaged by centrifugal hydraulic pressure. A centrifugal cancel piston 8 and a return spring 9 are provided to prevent this.

Further, the drum 6 has a fastening hydraulic hole 6d for transmitting hydraulic pressure to the clutch pack 7 and a lubricating hole 6e for supplying lubricating oil to the clutch pack 7 and the centrifugal cancel piston 8. Formed, in addition,
A recess 6f is formed on the outer periphery of the position where the lubrication hole 6e is provided. That is, the lubrication hole 6e is formed at a position overlapping the bearing 6b in the radial direction, and the recess 6f is formed at a position of the gap 10 between the bearing 6b and the fixing member 4. .

A lubricating circuit 11 for supplying lubricating oil to the gap 10 and the bearing 6b is formed in the fixing member 4. The lubricating circuit 11 includes a circuit 11a formed in the fixing member 4 in a direction orthogonal to the axis, a circuit 11b formed by slightly inclining in the axial direction from the tip of the circuit 11a, and a shaft extending from the tip of the circuit 11b. Circuit 1 drilled in the orthogonal direction
It is composed of 1c and 11d.

Therefore, in this embodiment, the lubricating oil supplied from the oil pump (not shown) to the lubricating circuit 11 via the control valve and the transmission case is supplied to the circuit 11d.
Is supplied from the circuit 11c to the centrifugal cancel piston 8 through the gap 10, the recess 6f, and the lubricating hole 6e.

As a result, the amount of lubricating oil to the centrifugal cancel piston 8 is stabilized and ensured, the operation of the centrifugal cancel piston 8 is ensured, the drift-on ball is eliminated, and the diameter of the centrifugal cancel piston 8 is reduced. There is.

In addition, in this embodiment, since the recess 6f is provided outside the lubrication hole 6e, it is possible to dispose the lubrication hole 6e in the radial direction so as to overlap with the bearing 6b. Achieved compactness by shortening the axial dimension.

Although the embodiment of the present invention has been described above with reference to the drawings, the specific configuration is not limited to this embodiment.

[0021]

As described above, in the automatic transmission according to the present invention, the case or the fixed member is formed with the lubricating circuit for supplying the lubricating oil to the centrifugal cancel piston. By supplying lubricating oil, this stabilizes the amount of lubricating oil to the centrifugal cancel piston and ensures the operation of the centrifugal cancel piston, as well as the abolition of the drift-on ball and the small diameter of the centrifugal cancel piston. The effect that it can be achieved is obtained.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an automatic transmission according to an embodiment of the present invention.

[Explanation of symbols]

 4 Fixed member 8 Centrifugal cancel piston 11 Lubrication circuit

Claims (1)

[Claims] 1. A clutch pack having a centrifugal cancel piston is rotatably supported by a case or a fixing member fixed to the case via a bearing, and the case or the fixing member is provided with lubricating oil for the centrifugal cancel piston. An automatic transmission characterized in that a lubrication circuit for supplying air is formed.