US 6,616,577 B2 · Clutch control apparatus

Abstract

Clutch disengagement shock resulting from the sudden release of torsional torque is prevented and ride-feeling at the time of changing gears or starting at a low-speed gear stage in an automatic clutch vehicle is improved. In a clutch control arrangement for controlling the engagement and disengagement of a friction-type clutch (1) by means of a clutch actuator (3) and a control unit (14), clutch disengagement speed is reduced when, at least, a gear-changing operation by a driver is detected, and the transmission (20) is in a low-speed gear stage. Even when the clutch is automatically disengaged at gear change, since disengagement speed is reduced if the current gear stage is a low-speed gear stage, the clutch (1) is not abruptly disengaged, enabling the prevention of clutch disengagement shock due to the sudden release of torsional torque. Because high torsional torque is normally transmitted to the drive system when either the clutch is in a partly engaged state or the accelerator stroke is large, it is desirable to reduce disengagement speed in these states.

Claims20

Dependent claims

A clutch control apparatus for controlling engagement and disengagement of a friction-type clutch comprising:

a clutch actuator for driving engagement and disengagement of a clutch;
and
a control unit for issuing a clutch engage/disengage command to the clutch actuator, the improvement further comprising:
gear-change operation detecting means for detecting a gear-change operation by a driver;
gear stage detecting means for detecting the current gear stage of a transmission;
and
clutch disengagement speed reducing means for setting clutch disengagement speed to low speed when at least the conditions that a gear-change operation by a driver has been detected and the transmission is in a low-speed gear stage are satisfied.

4 more elements

An automatic clutch vehicle which controls engagement/disengagement of a friction clutch based on a control signal outputted from an electronic control unit, comprising:

a motor which is turned ON for clutch disengagement, and turned OFF for clutch engagement by said electronic control unit, and supply power to which is controlled by said electronic control unit during the state in which the motor is turned ON;
a hydraulic pump which is driven by the motor;
a first cylinder which is connected via a check valve to the hydraulic pump and which has pistons on the inlet side and the outlet side respectively;
a second cylinder which is connected to the first cylinder and which engages/disengages said clutch;
electromagnetic valves which are turned ON for clutch engagement and turned OFF for clutch disengagement by said electronic control unit and which discharge oil from said first cylinder during the state in which the electromagnetic valves is turned ON;
a clutch pedal;
and
a master cylinder for supplying and discharging oil pressure of the first cylinder in accordance wit the actuation/release of the clutch pedal,
wherein, for automatic disengagement of the clutch, an output oil of said hydraulic pump pushes open the check valve and moves the two pistons of said first cylinder in opposite directions, and oil pressure is supplied to said second cylinder by the pushing movement of said outlet-side piston, causing the clutch to be disengaged by the second cylinder;
and
for manual disengagement of the clutch, an output oil of said master cylinder simultaneously pushes the two pistons of said first cylinder to the outlet side, and oil pressure is thereby sent to said second cylinder, causing the clutch to be disengaged by said second cylinder,
wherein said automatic clutch vehicle further comprises:
a gear-change operation detecting switch that is operated by a driver for detecting a gear-change operation by a driver;
a gear stage detecting sensor disposed in a transmission for detecting the current gear stage of the transmission;
a clutch stroke sensor for detecting the stroke of said clutch for determining whether or not aid clutch is in a partly engaged state;
and
an accelerator stroke sensor for detecting an accelerator stroke, and
wherein said electronic control unit, based on the outputs of the switch and sensors, slows down clutch disengagement speed either when a gear-change operation is detected and it is determined that the transmission is in a low-speed gear stage and that the clutch is in a partly engaged state, or when a gear-change operation is detected and it is determined that the transmission is in a low-speed gear stage and that the clutch is not in a partly engaged state and that an accelerator stroke is greater than a predetermined value.

15 more elements

Dependencies are inferred from the claim text.

Clutch control apparatus

Life of this patent

Clutch control apparatus

Life of this patent

Abstract

Claims20