Clutch control system for vehicle

Patent metadata

Field	Value
Publication number	US-9637130-B2
Application number	US-201514970426-A
Country	US
Kind code	B2
Filing date	Dec 15, 2015
Priority date	Dec 16, 2014
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

A clutch control system for vehicle is applied to a vehicle having a clutch and a transmission disposed in a power transmission path from an engine to a vehicle wheel. The system includes a first rotational speed detecting unit to detect a driving side rotational speed of the clutch, a second rotational speed detecting unit to detect a driven side rotational speed of the clutch, a half-clutch control unit, and a half-clutch transition control unit. The half-clutch control unit executes a first half-clutch control on the clutch actuator when a gear position of the transmission and a rotational direction of a driven side portion of the clutch are matched and executes, on the clutch actuator, a second half-clutch control, differing from the first half-clutch control, when the gear position of the transmission and the rotational direction of the driven side portion of the clutch are not matched.

First claim

What is claimed is:

1. A clutch control system for a vehicle having an engine, a vehicle wheel, a clutch disposed in a power transmission path from the engine to the vehicle wheel and a transmission disposed in the power transmission path,
the clutch having a driving side portion and a driven side portion disposed respectively at an engine side on the power transmission path and a vehicle wheel side on the power transmission path,
the vehicle including a clutch actuator that controls engagement and disengagement of the driving side portion and the driven side portion to each other,
the transmission being arranged to enable selection among a plurality of gear positions including
a forward gear position at which a driving force of the engine is converted to a rotational force in a forward movement direction of the vehicle wheel, and
a reverse gear position at which the driving force of the engine is converted to a rotational force in a reverse movement direction of the vehicle wheel,

the clutch control system for the vehicle comprising:
a first rotational speed detecting unit that detects a driving side rotational speed corresponding to a rotational speed of the driving side portion of the clutch;
a second rotational speed detecting unit that detects a driven side rotational speed corresponding to a rotational speed of the driven side portion of the clutch;
a target rotational speed setting unit that sets, as a target rotational speed corresponding to full accelerator closure, a value lower than a value equivalent to an idling engine speed of the engine;
a half-clutch control unit programmed to perform half-clutch control of the clutch actuator so as to
increase a mutual pressing force of the driving side portion and the driven side portion to each other if the driving side rotational speed is higher than the target rotational speed, and
decrease the mutual pressing force if the driving side rotational speed is lower than the target rotational speed; and

a half-clutch transition control unit programmed to perform a transition to the half-clutch control of the clutch actuator by the half-clutch control unit when both
the clutch is in a disengaged state so that the driving and driven side portions are disengaged from each other, and
at least one condition among the following is met:
a first condition that the driven side rotational speed is higher than the driving side rotational speed, and
a second condition that the driven side rotational speed is not less than a predetermined value.

2. The clutch control system for the vehicle according to claim 1 , wherein the target rotational speed setting unit sets the value of the target rotational speed corresponding to full accelerator closure to be higher than a value equivalent to a lower limit engine speed at which the engine can be kept running.

3. The clutch control system for the vehicle according to claim 1 , wherein the target rotational speed setting unit sets the target rotational speed variably in accordance with the idling engine speed when the half-clutch transition control unit performs the transition to the half-clutch control.

4. The clutch control system for the vehicle according to claim 1 , wherein the half-clutch control unit is programmed to variably set a changing amount of the pressing force in accordance with a difference between the driving side rotational speed and the target rotational speed.

5. The clutch control system for the vehicle according to claim 4 , wherein the half-clutch control unit is programmed to set the changing amount to increase as the difference increases.

6. A clutch control system for a vehicle having an engine, a vehicle wheel, a clutch disposed in a power transmission path from the engine to the vehicle wheel and a transmission disposed in the power transmission path,
the clutch having a driving side portion and a driven side portion disposed respectively at an engine side on the power transmission path and a vehicle wheel side on the power transmission path,
the vehicle including a clutch actuator that controls engagement and disengagement of the driving side portion and the driven side portion to each other,
the transmission being arranged to enable selection among a plurality of gear positions including
a forward gear position at which a driving force of the engine is converted to a rotational force in a forward movement direction of the vehicle wheel, and
a reverse gear position at which the driving force of the engine is converted to a rotational force in a reverse movement direction of the vehicle wheel,

the clutch control system for the vehicle comprising:
a first rotational speed detecting unit that detects a driving side rotational speed corresponding to a rotational speed of the driving side portion of the clutch;
a second rotational speed detecting unit that detects a driven side rotational speed corresponding to a rotational speed of the driven side portion of the clutch;
a target clutch torque setting unit that sets, as a target clutch torque corresponding to full accelerator closure, a value
greater than a value equivalent to an engine torque generated by the engine at an idling engine speed, and
less than a value equivalent to an engine torque generated by the engine at a predetermined engine speed lower than the idling engine speed;

a clutch torque acquisition unit that acquires an actual clutch torque transmitted from the driving side portion to the driven side portion;
a half-clutch control unit programmed to perform half-clutch control of the clutch actuator so as to
increase a mutual pressing force of the driving side portion and the driven side portion to each other if the actual clutch torque is lower than the target clutch torque, and
decrease the pressing force if the actual clutch torque is higher than the target clutch torque; and

a half-clutch transition control unit programmed to perform a transition to the half-clutch control of the clutch actuator by the half-clutch control unit when both
the clutch is in a disengaged state so that the driving and driven side portions are disengaged from each other, and
at least one condition among the following is met:
a first condition that the driven side rotational speed is higher than the driving side rotational speed, and
a second condition that the driven side rotational speed is not less than a predetermined value.

7. The clutch control system for the vehicle according to claim 6 , wherein the target clutch torque setting unit sets the value of the target clutch torque corresponding to full accelerator closure, to be equivalent to an engine torque generated by the engine at a lower limit engine speed at which the engine can be kept running.

8. The clutch control system for the vehicle according to claim 6 , wherein the target clutch torque setting unit sets the target clutch torque variably in accordance with the idling engine speed when the half-clutch transition control unit performs the transition to the half-clutch control.

9. The clutch control system for the vehicle according to claim 6 , wherein the half-clutch control unit is programmed to variably set a changing amount of the pressing force in accordance with a difference between the actual clutch torque and the target clutch torque.

10. The clutch control system for the vehicle according to claim 9 , wherein the half-clutch control unit is programmed to set the changing amount to increase as the difference increases.

11. The clutch control system for the vehicle according to claim 1 , wherein
the vehicle includes one rotational shaft between the driven side portion of the clutch and the vehicle wheel, and
the second rotatio

Assignees

• Yamaha Motor Co Ltd

Inventors

• Minami Kengo

Classifications

• B60W2510/0241

  Clutch slip, i.e. difference between input and output speeds · CPC title

• F16D2500/30806

  Engaged transmission ratio · CPC title

• B60W2510/0657

  Engine torque · CPC title

• F16D2500/70404

  Force · CPC title

• B60W10/06

  including control of combustion engines · CPC title