THROTTLE OPENING CONTROL DEVICE, MOTORCYCLE, AND METHOD FOR PRODUCING CONTROL MAP

• US 20090229568A1
• Filed: 03/12/2009
• Published: 09/17/2009
• Est. Priority Date: 03/17/2008
• Status: Active Grant

• Current Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Original Assignee: Yamaha Hatsudoki Kabushiki Kaisha (Yamaha Corporation)
• Inventors: Nakagawa, Yoshitomi
• Granted Patent: US 8,196,562 B2
• Time in Patent Office: Days
• US Class Current: 123/342
• CPC Class Codes: F02D 11/105 characterised by the function converting demand to actuation, e.g. a map indicating relations between an accelerator pedal position and throttle valve opening or target engine torque
• CPC Class Codes: F02D 11/106 Detection of demand or actuation
• CPC Class Codes: F02D 11/107 Safety-related aspects
• CPC Class Codes: F02D 2200/501 Vehicle speed
• CPC Class Codes: F02D 2250/06 Reverse rotation of engine
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/0097 using means for generating speed signals
• CPC Class Codes: F02D 9/00 Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A throttle opening control device for a vehicle having an engine with an electronically controlled throttle valve and an accelerator operated by a rider is provided. The throttle opening control device includes an accelerator opening acquisition module for acquiring an opening of the accelerator, an engine rotation speed acquisition module for acquiring a rotation speed of the engine, and a throttle opening control module for controlling an opening of the throttle valve based on the opening of the accelerator and the rotation speed of the engine. The throttle opening control module is configured to limit the opening of the throttle valve when the rotation speed of the engine is lower than a pre-determined idle rotation speed to prevent reverse rotation of the engine.

Claims

1. A throttle opening control device for a vehicle having an engine with an electronically controlled throttle valve and an accelerator operated by a rider, the throttle control device comprising:

an accelerator opening acquisition module for acquiring an opening of the accelerator based on an input from an accelerator opening sensor;

an engine rotation speed acquisition module for acquiring a rotation speed of the engine based on an input from an engine speed sensor; and

a throttle opening control module for controlling an opening of the throttle valve based on the opening of the accelerator and the rotation speed of the engine, wherein the throttle opening control module is configured to limit the opening of the throttle valve when the rotation speed of the engine is lower than a pre-determined idle rotation speed.

2. The throttle opening control device as claimed in claim 1, further comprising

memory for holding a control map that relates the opening of the throttle valve to the opening of the accelerator and the rotation speed of the engine and in which the opening of the throttle is limited for rotational speeds of the engine less than the pre-determined idle rotation speed,

wherein the throttle opening control module controls the opening of the throttle valve based on the control map.

3. The throttle opening control device as claimed in claim 1, wherein the throttle opening control module controls the opening of the throttle valve so as to prevent occurrence of reverse rotation of the engine.

4. The throttle opening control device as claimed in claim 2, wherein in the control map limits the opening of the throttle valve so as to prevent occurrence of reverse rotation of the engine.

5. The throttle opening control device as claimed in claim 2, wherein the control map is produced based on tests performed to determine whether or not reverse rotation of the engine occurs when the opening of the throttle valve is increased in a state where the rotation speed of the engine is lower than the idle rotation speed.

6. The throttle opening control device as claimed in claim 1, wherein the throttle opening control module sets the opening of the throttle valve to a constant, irrespective of the opening of the accelerator, over at least a portion of a range in which the rotation speed of the engine is lower than the pre-determined idle rotation speed and the opening of the accelerator is greater than or equal to a specified opening.

7. The throttle opening control device as claimed in claim 1, wherein the throttle opening control module limits the opening of the throttle valve so that it is less than the opening of the throttle valve when the rotation speed of the engine is zero in at least a portion of a range in which the rotation speed of the engine is lower than the pre-determined idle rotation speed.

8. A motorcycle provided with the throttle opening control device as claimed in claim 1.

9. A motorcycle provided with the throttle opening control device as claimed in claim 2.

10. A motorcycle provided with the throttle opening control device as claimed in claim 3.

11. A motorcycle provided with the throttle opening control device as claimed in claim 4.

12. A motorcycle provided with the throttle opening control device as claimed in claim 5.

13. A motorcycle provided with the throttle opening control device as claimed in claim 6.

14. A motorcycle provided with the throttle opening control device as claimed in claim 7.

15. A method for producing a control map for a throttle control device for a vehicle engine having an accelerator adapted to be operated by an operator and an electronically controlled throttle under control of the throttle control device, the method comprising the steps of:

adjusting a throttle opening of the engine such that the engine rotation speed becomes lower than a pre-determined idle rotation speed of the engine;

increasing the throttle opening in a state defined by the engine rotation speed being lower than the idle rotation speed;

determining whether reverse rotation of the engine occurs in the defined state;

recording the corresponding engine rotation speed and increased throttle opening values in the defined state; and

utilizing recorded engine rotation speed and throttle opening values for which reverse rotation of the engine does not occur to set up the control map.

16. An engine control unit for a vehicle having an engine with an electronically controlled throttle valve and an accelerator operated by a rider, the engine control unit comprising:

a first module configured to acquire the degree of opening of the accelerator;

a second module configured to acquire the rotation speed of the engine;

a third module configured to control the opening of the throttle valve of the engine on the basis of the acquired accelerator opening and engine rotation speed; and

a control map relating throttle opening, accelerator opening and engine rotation speed in a pre-determined manner, the third module determining the throttle valve opening based on the acquired accelerator opening and engine rotation speed with reference to the control map, wherein the third module limits the opening of the throttle valve when the engine rotation speed is lower than a pre-determined idle rotation speed of the engine to prevent reverse rotation of the engine.

17. The engine control unit of claim 16, wherein the third module is configured to correct the throttle opening determined from the control map based on input from a plurality of engine sensors and determine a corresponding final throttle opening.

18. The engine control unit of claim 17, wherein the plurality of engine sensors includes a water temperature sensor and an atmospheric pressure sensor.

19. The engine control unit of claim 16, wherein the control map is a three-dimensional map.

20. The engine control unit of claim 16, wherein the control map is produced on the basis of whether or not reverse rotation of the engine occurs when the opening of the throttle valve is increased in a state in which the rotation speed of the engine is lower than the idle rotation speed.

21. The engine control unit of claim 16, wherein the throttle opening control module sets the opening of the throttle valve to a substantially constant value, irrespective of the opening of the accelerator, over at least a portion of a range in which the rotation speed of the engine is lower than the pre-determined idle rotation speed and the opening of the accelerator is greater than or equal to a specified opening.

22. The engine control unit of claim 21, wherein the throttle opening control module limits the opening of the throttle valve so that it is less than the opening of the throttle valve when the rotation speed of the engine is zero in at least a portion of a range in which the rotation speed of the engine is lower than the pre-determined idle rotation speed.

23. A throttle opening control system for a vehicle engine having an accelerator adapted to be operated by an operator, the throttle opening control system comprising:

an electronically controlled throttle;

a plurality of engine sensors; and

an engine control unit configured to control the operation of the electronically controlled throttle on the basis of input signals from the plurality of engine sensors, the engine control unit comprising;

a first module configured to acquire the degree of opening of the accelerator;

a second module configured to acquire the rotation speed of the vehicle engine;

a third module for controlling the opening of the electronically controlled throttle on the basis of the acquired accelerator opening and engine rotation speed; and

a control map relating throttle opening, accelerator opening and engine rotation speed in a pre-determined manner, the third module configured to determine a throttle opening corresponding to the acquired accelerator opening and engine rotation speed with reference to the control map, wherein the third module limits the opening of the electronically controlled throttle when the engine rotation speed is lower than a pre-determined idle rotation speed of the engine to prevent reverse rotation of the engine.