Transmission

Patent metadata

Field	Value
Publication number	US-9776637-B2
Application number	US-201514972331-A
Country	US
Kind code	B2
Filing date	Dec 17, 2015
Priority date	Dec 18, 2014
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A transmission changes gears in a MT system, an AT system, and an AMT system wherein unintended transition between an AT mode and a MT mode or between an AMT mode and a MT mode is prevented. A selector in a controller performs a mode selection control such that, when performing transition between the AT mode and the MT mode or between the AMT mode and the MT mode, the driver at least has to operate a mode switching switch while operating a clutch lever in an operation amount not smaller than a predetermined threshold.

First claim

What is claimed is:

1. A transmission comprising:
clutch actuators that disengage a clutch of a multi-speed transmission;
a shift actuator that performs gear shifting of the multi-speed transmission;
a controller that controls the clutch actuators and the shift actuator;
a clutch lever;
a lever operation amount detector that converts an operation amount of the clutch lever to an electrical signal and outputs the electrical signal to the controller; and
a shift switch that outputs a command of gear shifting by a driver to the controller; wherein
the controller performs control in an AMT mode, an AT mode, or a MT mode;
the AMT mode is an operation mode in which a series of shift change operations are performed by controlling the clutch actuators and the shift actuator in a coordinated manner when the shift change command is input by an operation of the shift switch by the driver, and the clutch actuator is controlled regardless of an operation of the clutch lever by the driver in a starting process and a stopping process;
the AT mode is an operation mode in which shift selection and the series of shift change operations are performed by controlling the clutch actuators and the shift actuator regardless of the operation of the shift switch by the driver, and the clutch actuator is controlled regardless of the operation of the clutch lever by the driver in the starting process and the stopping process;
the MT mode is an operation mode in which the series of shift change operations are performed by controlling the clutch actuators and the shift actuator in a coordinated manner when the shift change command is input by the operation of the shift switch by the driver, and the clutch actuators are controlled such that the clutch is operated with a clutch torque capacity corresponding to the operation of the clutch lever by the driver in at least one of the starting process and the stopping process;
a mode switching switch outputs a request to change the operation mode by the driver to the controller; and
the controller performs a mode selection control such that, when performing a mode transition between the AT mode and the MT mode or between the AMT mode and the MT mode, the driver at least has to operate the mode switching switch while operating the clutch lever with an operation amount not smaller than a predetermined threshold and an accelerator opening is not greater than a prescribed value.

2. The transmission according to claim 1 , wherein the controller includes a condition that a start control is not being performed to the mode transition between the AT mode and the MT mode or between the AMT mode and the MT mode.

3. The transmission according to claim 2 , wherein, when receiving the request to change the operation mode in the AMT mode, the controller selects:
the MT mode when the accelerator opening is not greater than the prescribed value, the operation amount of the lever is not smaller than the threshold, and a start control is not being performed;
the AT mode when the accelerator opening is not greater than the prescribed value and the operation amount of the lever is smaller than the threshold, or the start control is being performed; or
the AMT mode when the accelerator opening is greater than the prescribed value.

4. The transmission according to claim 2 , wherein, when receiving the request to change the operation mode in the AT mode, the controller selects:
the MT mode when the accelerator opening is not greater than the prescribed value, the operation amount of the lever is not smaller than the threshold, and the start control is not being performed;
the AMT mode when the accelerator opening is not greater than the prescribed value and the operation amount of the lever is smaller than the threshold, or the start control is being performed; or
the AT mode when the accelerator opening is greater than the prescribed value.

5. The transmission according to claim 2 , wherein, when receiving the request to change the operation mode in the MT mode, the controller selects:
the AMT mode when the accelerator opening is not greater than the prescribed value, the operation amount of the lever is not smaller than the threshold, and the start control is not being performed; or
the MT mode when the accelerator opening is greater than the prescribed value, the operation amount of the lever is smaller than the threshold, or the start control is being performed.

6. The transmission according to claim 2 , wherein the controller selects the AMT mode at a time of starting.

7. The transmission according to claim 1 , wherein transmission is a dual clutch transmission with a first clutch operated by a first clutch actuator and a second clutch operated by a second clutch actuator.

8. A vehicle comprising:
the transmission according to claim 1 .

9. A motorcycle comprising:
the transmission according to claim 1 .

10. A method, performed by a controller, for controlling a transmission with clutch actuators that disengage a clutch of a multi-speed transmission, the transmission further including a shift actuator that performs gear shift of the multi-speed transmission; a clutch lever; a lever operation amount detector that converts an operation amount of the clutch lever to an electrical signal and outputs the electrical signal to the controller; and a shift switch that outputs a command of gear shifting by a driver to the controller, the method comprising:
performing a control in an AMT mode, an AT mode, or a MT mode,
performing a series of shift change operations when an operation mode is the AMT mode by controlling the clutch actuators and the shift actuator in a coordinated fashion when a shift change command is input by an operation of the shift switch by the driver in a transmission operation during traveling, and the clutch actuator is controlled regardless of an operation of the clutch lever by the driver in a starting process and a stopping process;
performing a shift selection and the series of shift change operations when an operation mode is the AT mode by controlling the clutch actuators and the shift actuator regardless of the operation of the shift switch by the driver in the transmission operation during traveling, and the clutch actuator is controlled regardless of the operation of the clutch lever by the driver in the starting process and the stopping process; and
performing the series of shift change operations when an operation mode is the MT mode by controlling the clutch actuators and the shift actuator in a coordinated fashion when the shift change command is input by the operation of the shift switch by the driver in the transmission operation during traveling, and the clutch actuators are controlled such that the clutch is operated with a clutch torque capacity corresponding to the operation of the clutch lever by the driver in at least one of the starting process and the stopping process; wherein
a mode switching switch that outputs a request to change the operation mode by the driver to the controller unit is further provided; and
the controller performs a mode selection control such that, when performing a mode transition between the AT mode or the AMT mode and the MT mode, the driver at least has to operate the mode switching switch while operating the clutch lever with an operation amount not smaller than a predetermined threshold and an accelerator opening of an engine is not greater than a prescribed value.

11. The method for controlling a transmission according to claim 10 , further comprising:
adding a condition that a start control of a vehicle is not being performed to a condition of the mode transition between the AT mode or the AMT mode and the M

Assignees

• Yamaha Motor Co Ltd

Inventors

• Saitoh Tetsushi

Classifications

• F16D48/06

  Control by electric or electronic means, e.g. of fluid pressure · CPC title

• F16H61/0213

  characterised by the method for generating shift signals · CPC title

• B60W30/18 Primary

  Propelling the vehicle · CPC title

• B60W2710/022

  Clutch actuator position · CPC title

• B60W2540/16

  Ratio selector position · CPC title