JPH0989006A - Clutch booster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clutch booster capable of controlling the vibration of a clutch pedal produced during cutting of clutch connection without changing a conventional clutch operating mechanism. SOLUTION: A fixed diaphragm 21 for reducing compressed air pressure is provided in a compressed air supply passage 11 immediately before the poppet valve 18 of a control valve 6 as one element included in a group constituting a clutch booster 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clutch booster which suppresses vibration of a clutch pedal when a clutch is connected or disconnected.

[0002]

2. Description of the Related Art As shown in FIG. 2, a clutch actuating mechanism for a large truck or the like has a master cylinder 8 actuated by operation of a clutch pedal 7, an actuating shaft 3 connected to a clutch 4 via a lever 5, and a clutch. 4 is operated by connecting and disconnecting the power cylinder 4 and the hydraulic pressure supplied from the master cylinder 8 through the hydraulic pipe 9 by operating the clutch pedal 7, and sends compressed air proportional to the hydraulic pressure to the power cylinder 2. It is configured by a clutch booster 1 including a control valve 6. In FIG. 2, 10 is a hydraulic pressure supply port from the master cylinder 8, and 11 is a compressed air supply port of the control valve 6.

As shown in FIG. 3, the concrete construction of the clutch booster 1 comprises three groups of a power cylinder 2, a control valve 6 and a hydraulic cylinder 14 as one unit.

The power cylinder 2 has a built-in piston 12 which is moved forward by compressed air sent from the control valve 6 and is moved backward by a return spring 20. The piston 12 has a hydraulic cylinder 14 which will be described later. A push rod 13 is fixedly installed.

The control valve 6 contains a relay valve piston 16, a control valve chamber 17, a poppet valve 18, and a poppet valve spring 19 inside an end plate 23.

A hydraulic piston 15 is built in the hydraulic cylinder 14, one end of which is in contact with the push rod 13 and the other end is in contact with the actuating shaft 3. In addition, the boosting force generated in the power cylinder 2 is transmitted to the operating shaft 3 via the push rod 13.

[0007]

In the clutch booster of the clutch actuating mechanism as described above, the poppet valve 18 of the control valve 6 opens and closes at a high frequency when the clutch is connected and disconnected. When a large amount of air flows into the control valve 6, the shock is continuously transmitted to the hydraulic pressure, and this is reflected as the vibration of the clutch pedal 7 (rigid feeling or Kuckn's phenomenon).

In order to improve this, a method has been adopted in which an accumulator or a shock absorber is attached to the hydraulic pipe 9 of the transmission system to absorb the pulsation, but the structure becomes complicated and the number of parts and the cost are reduced. It was considered to be an issue for improvement.

An object of the present invention is to provide a clutch booster capable of suppressing the vibration of the clutch pedal which occurs when the clutch is engaged or disengaged, without modifying the conventional clutch actuating mechanism.

[0010]

The object of the present invention to achieve the above object is to provide a power cylinder that is connected to a clutch and operates to connect and disconnect the clutch, and a clutch pedal to directly operate the hydraulic pressure from a master cylinder. In a clutch booster consisting of a control valve that operates and sends compressed air proportional to hydraulic pressure to the power cylinder, a fixed throttle for reducing compressed air pressure is provided in the compressed air supply passage immediately before the poppet valve of the control valve. It is a feature.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a clutch booster, which includes a power cylinder 2 and a control valve 6.
Although not shown in FIG. 1, the three groups of hydraulic cylinders 14 are configured as one unit as shown in FIG.

The control valve 6 includes a relay valve piston 16, a control valve chamber 17, and a poppet valve 18 inside the end plate 23.
The point that the poppet valve spring 19 is incorporated is also the same as the conventional one.

In the present invention, a fixed throttle 21 for reducing the compressed air pressure is provided in the compressed air supply passage immediately before the poppet valve 18 of the control valve 6.

The compressed air supply passage immediately before the poppet valve 18 is connected to the compressed air supply port 11 by a union 22.
The inner diameter of the union 22, the fixed diaphragm 21
Is desirable.

Since the present invention is constructed as described above, the pressure reducing action of the fixed throttle 21 provided in the compressed air supply passage immediately before the poppet valve 18, that is, the inner diameter of the union 22 connected to the compressed air supply port 11. Thus, the amount of compressed compressed air flowing into the control valve 6 per opening / closing of the poppet valve 18 is reduced.

As a result, continuous shock due to the inflow of compressed air is eliminated, and the vibration of the clutch pedal at the time of clutch engagement / disengagement is suppressed.

The fixed throttle 21 has, for example, an inner diameter of 3.5 mm and a length of 17 mm. The fixed throttle 21 has a compressed air supply passage immediately before the poppet valve 18 and the poppet valve 18.
As a result of arranging it at a position far away from the test, the base pressure of 8.0 Kg / cm2 became 6.5 Kg / cm2 after depressurization, and the one arranged in the compressed air supply passage immediately before the poppet valve 18 vibrates the clutch pedal. Good data were obtained for the relationship between the effect of restraint and the side effect of the pedal effort of the clutch pedal.

[0018]

As described above, according to the present invention, it is possible to suppress the vibration of the clutch pedal generated at the time of engaging and disengaging the clutch with a simple structure without modifying the conventional clutch operating mechanism, and the number of parts and the cost are reduced. However, it has an advantageous effect.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of the present invention.

FIG. 2 is a general clutch operation mechanism diagram.

FIG. 3 is a sectional view of a conventional clutch booster.

[Explanation of Codes] 1 Clutch Booster 2 Power Cylinder 4 Clutch 6 Control Valve 7 Clutch Pedal 8 Master Cylinder 9 Hydraulic Piping 10 Hydraulic Supply Port 11 Compressed Air Supply Port 12 Piston 13 Push Rod 14 Hydraulic Cylinder 15 Hydraulic Piston 16 Relay Valve Piston 17 Control valve chamber 18 Poppet valve 19 Poppet valve spring 20 Return spring 21 Fixed throttle 22 Union 23 End plate

Claims (1)

[Claims] 1. A power cylinder, which is connected to a clutch and operates to connect and disconnect the clutch, and a control valve which operates directly by hydraulic pressure from a master cylinder by operating a clutch pedal and sends compressed air proportional to the hydraulic pressure to the power cylinder. In the above clutch booster, a fixed throttle for reducing the compressed air pressure is provided in the compressed air supply passage immediately before the poppet valve of the control valve.