Clutch control system

Patent metadata

Field	Value
Publication number	US-2016167666-A1
Application number	US-201514970366-A
Country	US
Kind code	A1
Filing date	Dec 15, 2015
Priority date	Dec 16, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

A clutch control system includes a hunting determining unit that determines whether or not a hunting condition, under which hunting occurs in an engine rotational speed of an engine, is met, and a clutch position control unit. The clutch position control unit executes a first clutch position control, which is in accordance with engine rotation information, on the clutch if the hunting determining unit determines that the hunting condition is not met, and executes a second clutch position control, which is lower in response to the engine rotation information than the first clutch position control, on the clutch if the hunting determining unit determines that the hunting condition is met.

First claim

What is claimed is:

1 . A clutch control system arranged to control a clutch interposed in a power transmission path from an engine to an actuated portion, the clutch control system comprising:
a rotational speed control unit programmed to execute a rotational speed suppression control of suppressing an engine rotational speed of the engine when a predetermined engine rotational speed suppression condition is met; and a clutch position control unit programmed to execute
if the rotational speed control unit is not executing the rotational speed suppression control, a first clutch position control, which is in accordance with engine rotation information, on the clutch, and if the rotational speed control unit is executing the rotational speed suppression control, a second clutch position control, which is lower in response to the engine rotation information as compared to a response of the first clutch position control to the engine rotation information, on the clutch.

2 . The clutch control system according to claim 1 , wherein the rotational speed suppression control includes a fuel supply cutting control of cutting a supply of fuel to the engine.

3 . The clutch control system according to claim 2 , wherein the engine includes a fuel injector, and the fuel supply cutting control includes an injection cutting control of cutting fuel injection by the fuel injector.

4 . The clutch control system according to claim 1 , wherein after the clutch position control unit executes the second clutch position control, the clutch position control unit is programmed to end the second clutch position control and transition to the first clutch position control a predetermined time after the rotational speed control unit ends the rotational speed suppression control.

5 . The clutch control system according to claim 1 , wherein the rotational speed control unit is programmed to set a determination flag to ON when the engine rotational speed suppression condition is met, and
the clutch position control unit is programmed to judge that the rotational speed suppression control is being executed when the determination flag is set to ON.

6 . The clutch control system according to claim 1 , wherein the second clutch position control includes position control of the clutch in accordance with filtered engine rotation information which is the engine rotation information being filtered in a filtering process.

7 . The clutch control system according to claim 6 , wherein the filtering process includes a process of determining calculated values using values for the engine rotation information at different time points within a predetermined time period.

8 . The clutch control system according to claim 6 , wherein the second clutch position control includes an ending process to end the second clutch position control by gradually weakening the filtering during the filtering process.

9 . The clutch control system according to claim 1 , wherein the second clutch position control includes a clutch disengage control of controlling the clutch to a disengagement position, without dependence on the engine rotation information, when a clutch engagement prohibition condition is met.

10 . The clutch control system according to claim 6 , wherein the second clutch position control includes
a clutch disengage control of controlling the clutch to a disengagement position if a clutch engagement prohibition condition is met, and a clutch engage control of controlling the clutch position in accordance with the filtered engine rotation information if the clutch engagement prohibition condition is not met.

11 . The clutch control system according to claim 9 , wherein the clutch engagement prohibition condition includes that the engine rotational speed is less than a predetermined rotational speed.

12 . The clutch control system according to claim 9 , wherein the first clutch position control ends another clutch disengage control if, during execution of the clutch disengage control, the engine rotational speed becomes less than a predetermined value with a throttle opening being fully closed,
the another clutch disengage control includes controlling the clutch to a disengagement position, without dependence on the engine rotation information.

13 . The clutch control system according to claim 1 , wherein the clutch control system is arranged to be included in a vehicle capable of switching between actuation and non-actuation of a differential lock, and
the engine rotational speed suppression condition includes that switching between the actuation and the non-actuation of the differential lock is in progress.

14 . The clutch control system according to claim 1 , wherein the engine rotational speed suppression condition includes that the engine rotational speed has reached a limit rotational speed associated with an oil pressure of the engine.

15 . The clutch control system according to claim 1 , wherein the engine rotational speed suppression condition includes that the engine rotational speed has reached a limit rotational speed associated with a temperature of cooling water for cooling the engine.

16 . A clutch control system arranged to control a clutch interposed in a power transmission path from an engine to an actuated portion, the clutch control system comprising:
a hunting determining unit that determines whether or not a hunting condition, under which hunting of an engine rotational speed of the engine occurs, is met; and a clutch position control unit programmed to execute
if the hunting determining unit determines that the hunting condition is not met, a first clutch position control, which is in accordance with engine rotation information, on the clutch, and
if the hunting determining unit determines that the hunting condition is met, a second clutch position control, which is lower in response to the engine rotation information as compared to a response of the first clutch position control to the engine rotation information, on the clutch.

17 . The clutch control system according to claim 16 , further comprising a rotational speed control unit programmed to execute a rotational speed suppression control of suppressing the engine rotational speed of the engine when a predetermined engine rotational speed suppression condition is met;
wherein the hunting determining unit determines
that the hunting condition is met when the rotational speed control unit is executing the rotational speed suppression control, and
that the hunting condition is not met when the rotational speed control unit is not executing the rotational speed suppression control.

18 . The clutch control system according to claim 16 , wherein the hunting determining unit is arranged to determine whether or not hunting of the engine rotational speed is actually occurring, and to determine that the hunting condition is met when hunting of the engine rotational speed is actually occurring.

19 . The clutch control system according to claim 18 , further comprising a rotational speed control unit programmed to execute a rotational speed suppression control of suppressing the engine rotational speed of the engine when a predetermined engine rotational speed suppression condition is met;
wherein the hunting determining unit determines that the hunting condition is met when both the rotational speed control unit is executing the rotational speed suppression control, and the hunting determining unit determines that hunting is actually occurring in the engine rotational speed

Assignees

• Yamaha Motor Co Ltd

Inventors

• Oohata Shinobu

Classifications

• B60W2510/0638

  Engine speed · CPC title

• B60W10/02

  including control of driveline clutches · CPC title

• B60W2710/021

  Clutch engagement state · CPC title

• F16D2500/7041

  Position · CPC title

• F16D2500/504

  Relating the engine · CPC title