Electronic throttle valve control system and two-wheeled motor vehicle

• US 7,461,630 B2
• Filed: 11/09/2004
• Issued: 12/09/2008
• Est. Priority Date: 11/12/2003
• Status: Active Grant

• Current Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Original Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Inventors: Matsuda, Takeshi, Yokoi, Masato, Kishi, Tomoaki, Maruo, Keisuke, Yamaguchi, Naoya
• Primary Examiner(s): SOLIS, ERICK R
• Application Number:
  US10/579,010
• Publication Number:
  US 20080022970A1
• Time in Patent Office: 1,491 Days
• Field of Search: 123/396, 123/397, 123/399
• US Class Current: 123/397
• CPC Class Codes: F02D 11/107 Safety-related aspects
• CPC Class Codes: F02D 2009/0277 Fail-safe mechanisms, e.g. with limp-home feature, to close throttle if actuator fails, or if control cable sticks or breaks
• CPC Class Codes: F02D 2011/102 at least one throttle being moved only by an electric actuator
• CPC Class Codes: F02D 2041/2072 Bridge circuits, i.e. the load being placed in the diagonal of a bridge to be controlled in both directions
• CPC Class Codes: F02D 2200/0404 Throttle position
• CPC Class Codes: F02D 2200/1012 Engine speed gradient
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 9/1065 Mechanical control linkage between an actuator and the flap, e.g. including levers, gears, springs, clutches, limit stops of the like
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

An electronic throttle valve control system prevents rapid rotation of a throttle valve reliably when the control system has a failure. A throttle valve controls the amount of intake air to an internal combustion engine, an electric motor drives the throttle valve, and a rotational speed reduction mechanism reduces the rotation of the electric motor to control the rotation of the throttle valve. An urging mechanism urges the throttle valve in the closing direction. An attenuation mechanism attenuates the speed at which the throttle valve is rotated in the closing direction by the urging mechanism when the control system has a failure. The attenuation mechanism is the electric motor in a regenerative mode or an air damper.

Claims

1. An electronic throttle valve control system having:

a throttle valve for controlling the amount of intake air to an internal combustion engine;

an electric motor for driving the throttle valve; and

a rotational speed reduction mechanism for reducing the rotation of the electric motor to control the rotation of the throttle valve;

further comprising;

an urging mechanism for urging the throttle valve in the closing direction; and

an attenuation mechanism for attenuating the speed at which the throttle valve is rotated in the closing direction by the urging force of the urging mechanism when the control system has a failure,

wherein at least one of the urging mechanism and the attenuation mechanism is connected to the rotational speed reduction mechanism.

2. The electronic throttle valve control system of claim 1, wherein the urging mechanism is incorporated in the rotational speed reduction mechanism and the attenuation mechanism is connected to the rotational speed reduction mechanism.

3. The electronic throttle valve control system of claim 1, wherein the rotational speed reduction mechanism is connected to the electric motor, and the electric motor is shifted to a regenerative mode and serves as the attenuation mechanism when the control system has a failure.

4. The electronic throttle valve control system of claim 1, wherein the internal combustion engine is a multi-cylinder internal combustion engine having a plurality of cylinders, each provided with a throttle valve, and the rotational speed reduction mechanism is located between two of the throttle valves.

5. The electronic throttle valve control system of claim 1, wherein the rotational speed reduction mechanism comprises a plurality of rotors provided between the electric motor and the throttle valve, and the urging mechanism is attached to at least one of the plurality of rotors.

6. The electronic throttle valve control system of claim 1, wherein the attenuation mechanism comprises a piston reciprocable in a cylinder and connected to the rotational speed reduction mechanism, and a resistance is applied to the reciprocating movement of the piston when the control system has a failure.

7. The electronic throttle valve control system of claim 6, wherein the piston is connected to the rotor which is closest to the throttle valve.

8. The electronic throttle valve control system of claim 1, wherein the throttle valve is rotated in the closing direction by the urging force of the urging mechanism and then held in a predetermined opening position when the control system has a failure.

9. The electronic throttle valve control system of claim 1, wherein the electronic throttle valve has a second urging mechanism for urging the throttle valve in the closing or opening direction.

10. The electronic throttle valve control system of claim 1, wherein the urging mechanism comprises a mechanism having a spring.

11. The electronic throttle valve control system of claim 5, wherein the rotors are reduction gears.

12. A two-wheeled motor vehicle provided with the electronic throttle valve control system according to claim 1.