Engine control system for outboard motor

• US 7,047,943 B1
• Filed: 07/27/2000
• Issued: 05/23/2006
• Est. Priority Date: 07/27/1999
• Status: Expired due to Term

• Current Assignee: Yamaha Marine Kabushiki Kaisha
• Original Assignee: Yamaha Marine Kabushiki Kaisha
• Inventors: Kanno, Isao
• Primary Examiner(s): Gimie, Mahmoud
• Application Number:
  US09/626,870
• Time in Patent Office: 2,126 Days
• Field of Search: 123/479, 123/480, 123/198.D, 123/333
• US Class Current: 123/479
• CPC Class Codes: F02B 61/045 for outboard marine engines
• CPC Class Codes: F02D 2200/0404 Throttle position
• CPC Class Codes: F02D 2200/0406 Intake manifold pressure
• CPC Class Codes: F02D 2200/0414 Air temperature
• CPC Class Codes: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: F02D 41/2422 Selective use of one or more tables

Abstract

A control system for an internal combustion engine includes a fuel injection control system having a first mode, wherein fuel injectors are controlled based on engine condition data supplied by a first group of sensors, and a second mode wherein fuel injectors are controlled based on engine condition data supplied by a second group of sensors. During normal operation of the engine, the control system switches between the first and second control modes based upon an engine operating condition (e.g., engine speed and/or engine load). If one of the sensors of the first group of sensors malfunctions, the control system controls the engine only in accordance with the second control mode. If one of the sensors of the second group of sensors malfunctions, the control system controls the engine only in accordance with the first control mode. In the case of a sensor malfunction in either of the first or second groups, the control system will reduce the engine speed as an alarm to apprise the operator of an engine malfunction.

Claims

1. An internal combustion engine comprising a throttle valve, an ignition system, a plurality of combustion chambers, a fuel delivery system adapted to deliver a fuel charge to each of the combustion chambers, a plurality of engine condition sensors adapted to detect associated engine condition data, and a control system, the control system adapted to receive the data from the engine condition sensors and further adapted to control operation of the fuel delivery system and the ignition system, the engine having a first operational state defined by a first range of throttle valve openings and a second operational state defined by a second range of throttle valve openings, and the control system having a default control condition wherein the control system controls the fuel delivery system in accordance with a first control mode with the engine running in the first operational state or controls the fuel delivery system in accordance with a second control mode with the engine running in the second operational state, the control system further being adapted to reduce engine speed upon a detection error of one of the sensors.

2. The engine of claim 1, wherein the fuel delivery system comprises a plurality of fuel injectors, and each fuel injector communicates with one of the combustion chambers.

3. The engine of claim 1, wherein the first control mode determines fuel delivery system control parameters in accordance with engine condition data detected by a first group of one or more sensors and the second control mode determines fuel delivery system control parameters in accordance with engine condition data detected by a second group of one or more sensors.

4. The engine of claim 3, wherein the first control mode determines fuel delivery system control parameters in accordance with engine condition data detected by an intake air pressure sensor and the second control mode determines fuel delivery system control parameters in accordance with engine condition data detected by a throttle angle sensor.

5. The engine of claim 4, wherein the control system is adapted to control the fuel delivery system in accordance with the first control mode in both the first and second operational states upon a malfunction of the throttle angle sensor.

6. The engine of claim 4, wherein the control system is adapted to control the fuel delivery system in accordance with the second control mode in both the first and second operational states upon a malfunction of the intake air pressure sensor.

7. The engine of claim 3, wherein the control system is adapted to control the fuel delivery system in accordance with the first control mode in both the first and second operational states upon a malfunction of one of the second group of one or more sensors.

8. The engine of claim 1, wherein the control system is adapted to reduce engine speed by delaying ignition timing.

9. The engine of claim 1, wherein the control system is adapted to reduce engine speed by disabling at least one combustion chamber.

10. The engine of claim 9, wherein the cylinder is disabled by the control system withholding fuel flow to the combustion chamber.

11. The engine of claim 1, wherein the control system is adapted to reduce engine speed by partially disabling the ignition system.

12. The engine of claim 1, wherein the control system is adapted to reduce engine speed by reducing the volume of fuel delivered to the combustion chambers of the engine.

13. The engine of claim 1 in combination with an outboard motor, the outboard motor comprising a cowling and a propulsion device, the engine being positioned within the cowling and being arranged to drive the propulsion device.

14. A method for controlling engine operation comprising the steps of providing a plurality of engine condition sensors adapted to detect engine operating conditions and relay engine condition data to a control unit, analyzing the data in the control unit, controlling fuel delivery amounts to at least one combustion chamber of the engine in accordance with a first control mode based upon engine condition data detected by a first group of one or more sensors, controlling fuel delivery amounts to at least the one combustion chamber in accordance with a second control mode based upon engine condition data detected by a second group of one or more sensors, controlling fuel delivery amounts only in accordance with the first control mode upon detection of a malfunction of a sensor of the second group of one or more sensors, controlling fuel delivery amounts only in accordance with the second control mode upon detecting a malfunction of a sensor of the first group of one or more sensors and actuating an alarm upon malfunction of one of the sensors.

15. The method of claim 14, wherein actuating the alarm comprises reducing engine speed.

16. The method of claim 15, wherein the engine speed is reduced by disabling at least one combustion chamber of the engine.

17. The method of claim 14 additionally comprising sensing an engine condition over first and second ranges, and switching between the first and second control modes depending upon whether the engine condition is in the first or second range.

18. An internal combustion engine comprising a throttle valve, an ignition system, at least one combustion chamber, a fuel injection system adapted to deliver a fuel charge to the combustion chamber, a plurality of engine condition sensors adapted to detect associated engine condition data, and a control system, the control system adapted to receive the data from the engine condition sensors and further adapted to control operation of the fuel injection system, the control system controlling operation of the fuel injection system in accordance with a first operational mode when a first range of an engine condition is detected by a first engine condition sensor or in accordance with a second operational mode when a second range of the engine condition is detected by the first engine condition sensor, the control system determining a fuel injection amount based upon a first set of parameters received from a first group of engine condition sensors when operating under the first operational mode and upon a second set of parameters received from a second group of engine condition sensors when operating under the second operational mode, and further being configured to signal malfunctioning of the engine in the event that one of the engine condition sensors of either the first or second group fails.

19. The engine of claim 18, wherein the control system is adapted to limit engine speed to signal engine malfunction.

20. The engine of claim 19, wherein the control system reduces engine speed by at least partially disabling at least one of the cylinders.

21. The engine of claim 18, wherein the control system activates a light to signal engine malfunction.

22. The outboard motor of claim 18, wherein the first engine condition sensor comprises a throttle valve angle sensor.

23. The outboard motor of claim 22, wherein the first range of engine conditions comprises small throttle angles, and the second range of engine conditions comprises large throttle angles.

24. The outboard motor of claim 18, wherein the engine condition sensors of the first and second groups are chosen from a group consisting of an intake air pressure sensor, engine speed sensor, and throttle valve angle sensor.