Transmission, vehicle having the transmission, and control device and control method for the transmission

• US 8,090,509 B2
• Filed: 01/29/2008
• Issued: 01/03/2012
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Original Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Inventors: Asaoka, Ryousuke
• Primary Examiner(s): Hellner, Mark
• Assistant Examiner(s): Algahaim, Helal A
• Application Number:
  US12/021,902
• Publication Number:
  US 20080183357A1
• Time in Patent Office: 1,435 Days
• Field of Search: 701/51, 701/61, 477/46, 477/68
• US Class Current: 701/51
• CPC Class Codes: F16H 61/66259 using electrical or electronical sensing or control means
• CPC Class Codes: F16H 63/062 electric or electro-mechanical actuating means

Abstract

A transmission includes a gear ratio change mechanism, a driving circuit and an electronic control unit (ECU). The gear ratio change mechanism has a motor for continuously varying the gear ratio. The driving circuit applies a pulse voltage to the motor. The ECU outputs a control signal to the driving circuit. The duty ratio and/or the pulse height of the pulse voltage is changed according to the control signal. The ECU performs a low-pass filtering process on the control signal to output the low-pass filtered control signal to the driving circuit. Gear ratio change shocks are thereby suppressed.

Claims

1. A transmission comprising:

a gear ratio change mechanism having a motor for continuously varying a gear ratio between an input shaft and an output shaft;

a motor driving section for applying a pulse voltage to the motor; and

a control section for outputting to the motor driving section an output control signal for changing at least one of a duty ratio and a pulse height of the pulse voltage,

wherein the control section outputs to the motor driving section as the output control signal a low-pass filtered control signal after applying a low-pass filtering process to another control signal.

2. The transmission according to claim 1, wherein the control section always applies the low-pass filtering process to the another control signal.

3. The transmission according to claim 1, wherein the control section selectively applies the low-pass filtering process to the another control signal.

4. The transmission according to claim 3, wherein the control section applies the low-pass filtering process to the another control signal only when the gear ratio is changed significantly.

5. The transmission according to claim 3, wherein the control section applies the low-pass filtering process to the another control signal only upon selection of a mode to apply the low-pass filtering process.

6. The transmission according to claim 1, wherein the another control signal is a pulse width modulation control signal for controlling the duty ratio of the pulse voltage.

7. The transmission according to claim 1, wherein the another control signal is a pulse amplitude modulation control signal for controlling the pulse height of the pulse voltage.

8. The transmission according to claim 1, wherein the low pass filtering process has a relatively low cut off frequency.

9. A vehicle comprising the transmission according to claim 1.

10. The vehicle according to claim 9, further comprising:

a driving source connected to the input shaft to form a driving source unit in conjunction with the transmission; and

a body frame, wherein the driving source unit is directly and pivotably attached to the body frame.

11. A two wheeled motorized vehicle comprising the transmission according to claim 1.

12. A control device for a gear ratio change mechanism having a motor for continuously varying a gear ratio between an input shaft and an output shaft, the control device comprising:

a motor driving section for applying a pulse voltage to the motor to continuously vary the gear ratio between the input shaft and the output shaft; and

a control section for outputting to the motor driving section an output control signal for changing at least one of a duty ratio and a pulse height of the pulse voltage,

wherein the control section outputs to the motor driving section as the output control signal a low-pass filtered control signal after applying a low-pass filtering process to another control signal.

13. A control method for a gear ratio change mechanism having a motor for continuously varying a gear ratio between an input shaft and an output shaft, the control method comprising:

applying a low-pass filtering process to a control signal for changing at least one of a duty ratio and a pulse height of a pulse voltage to continuously vary the gear ratio between the input shaft and the output shaft; and

applying to the motor the pulse voltage controlled by the low-pass filtered control signal to drive the motor.

14. The control method according to claim 13, wherein the low-pass filtering process is always applied to the control signal.

15. The control method according to claim 13, wherein the low-pass filtering process is selectively applied to the control signal.

16. The control method according to claim 15, wherein the low-pass filtering process is applied to the control signal only when the gear ratio is changed significantly.

17. The control method according to claim 15, wherein the low-pass filtering process is applied to the control signal only when a mode is selected to apply the low-pass filtering process.

18. The control method according to claim 13, wherein the another control signal is a pulse width modulation control signal that is applied to control the duty ratio of the pulse voltage.

19. The control method according to claim 13, wherein the another control signal is a pulse amplitude modulation control signal that is applied to control the pulse height of the pulse voltage.

20. The control method according to claim 13, wherein the low pass filtering process has a relatively low cut off frequency.