Method and apparatus for controlling a power delivery system having a continuously variable ratio transmission

• US 4,699,025 A
• Filed: 09/30/1985
• Issued: 10/13/1987
• Est. Priority Date: 09/30/1985
• Status: Expired due to Term

• Current Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Original Assignee: Aisin Seiki Co., Ltd. (Aisin Corp.)
• Inventors: Omitsu, Takashi
• Primary Examiner(s): Braun, Leslie
• Assistant Examiner(s): Diehl, Dwight G.
• Application Number:
  US06/781,502
• Time in Patent Office: 743 Days
• Field of Search: 364/424.1, 364/431.09, 74/866, 74/865, 74/877
• US Class Current: 477/43
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/101 Infinitely variable gearings
• CPC Class Codes: B60W 10/107 with endless flexible members
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• CPC Class Codes: F16H 2302/00 Determining the way or trajectory to new ratio, e.g. by determining speed, torque or time parameters for shift transition
• CPC Class Codes: F16H 61/66 specially adapted for continuously variable gearings control of exclusively fluid gearing F16H61/38
• CPC Class Codes: F16H 61/66254 controlling of shifting being influenced by a signal derived from the engine and the main coupling

Abstract

A control system and method for a power delivery system, such as in an automotive vehicle, having an engine coupled to a continuously variable ratio transmission (CVT). Totally independent control of engine and transmission enable the engine to precisely follow a desired operating characteristic, such as the ideal operating line for low fuel consuption. CVT ratio is controlled as a function of commanded desired system performance (e.g., power or torque) and measured actual system performance, such as CVT torque output, while engine fuel requirements (e.g., throttle position) are strictly a function of measured engine speed. Fuel requirements are therefore precisely adjusted in accordance with the ideal characteristics for any load placed on the engine. Appropriate controls prevent anomalous engine and vehicle behavior, and allow for transient start-up from test. The lag between a commanded change in torque or power of the power delivery system and the time the commanded torque is actually produced in also shortened.

Claims

1. A system for controlling the operation of a power delivery system including an engine and a continuously variable ratio transmission coupled to said engine for delivering power from said engine to an output shaft, said engine having fuel delivery means for delivering a variable quantity of fuel thereto, said power delivery system being controlled by command means for commanding a desired power delivery system performance, wherein said engine is maintained along an ideal operating line as a function of engine speed, said system comprising:

actual system performance measuring means for measuring the actual performance of the power delivery system;

ratio control means operatively coupled to said command means and said actual system performance measuring means for controlling the ratio of said transmission as a function of the desired system performance commanded by said command means and the measured actual system performance, the speed of said engine varying as a function of transmission ratio;

command power controller means for providing a signal representing accelerator pedal position; and

control means coupled to said command power controller means which includes compensating means for providing a compensating signal as a function of said signal representing accelerator pedal position, said compensating means includes a compensator and a gain controller and wherein the fuel delivered to said engine by said fuel delivery means is dependent on said compensating signal.

2. The system of claim 1 wherein said actual performance of said power delivery system is a function of the speed of said engine.

3. The system of claim 1 further including fuel function means defining a desired fuel requirement for said engine in relation to engine operating speed.

4. The system of claim 3 wherein said signal is modified in accordance with said fuel function means to control said delivery means.

5. The system of claim 1 wherein said commanded system performance is modified in accordance with a predetermined function.

6. The system of claim 1 wherein said control means is coupled to said actual system performance measuring means.

7. The system of claim 1 wherein said fuel delivery means includes an engine throttle valve.

8. A system for controlling the operation of a power delivery system including an engine and a continuously variable ratio transmission coupled to said engine for delivering power from said engine to an output shaft, said engine having fuel delivery means for delivering a variable quantity of fuel thereto, said power delivery system being controlled by command means for commanding a desired power delivery system performance, said system comprising:

power command signal means included within said command means for providing a power command signal;

commanded power control means coupled to said command means for receiving said power command means signal and providing a commanded power signal, said commanded power signal being a function of said power command signal;

actual system measuring means for measuring the actual performance of said power delivery system and providing a system performance signal ;

power change means coupled to said commanded power control means and said actual system measuring means for receiving said commanded power signal and said system performance signal and providing a power change signal;

conversion means coupled to said power change means for converting said power change signal to a fuel delivery means control signal for controlling said fuel delivery means; and

compensating means coupled to said commanded power control means for providing a compensating signal as a function of said power command signal, said compensating means includes a compensator and a gain controller wherein the fuel delivered to said engine by said fuel delivery means is dependent on said compensating signal.

9. The system of claim 8 further including ideal fuel delivery control means for determining the ideal operation of said fuel delivery means to maintain the operation of said engine along an ideal operating line and providing a corresponding ideal fuel delivery means control signal, wherein said conversion means adds said fuel delivery means control signal to said ideal fuel delivery means control signal to control said fuel delivery means.