Method and apparatus for controlling reduction ratio of continuously variable transmission with accelerator pedal displacement speed compensation
AssigneeNissan Motor Co., Ltd.
InventorsKeiju Abo, Haruyoshi Kumura, Hiroyuki Hirano, Yoshikazu Tanaka, Sigeaki Yamamuro, Yoshiro Morimoto
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Abstract
A method and an apparatus controls a reduction ratio of a continuously variable transmission of an automotive vehicle, wherein the reduction ratio is increased when the depression degree of the accelerator pedal is increased rapidly for ensuring quick acceleration. When the depression degree of the accelerator pedal is decreased rapidly, the reduction ratio is held for a predetermined period of time. Under this condition, the reduction ratio may be controlled to accomplish a predetermined deceleration.
Claims49
A method from controlling a reduction ratio of a continuously variable transmission of an automotive vehicle having a brake pedal and an internal combustion engine with an accelerator pedal, comprising the steps of:
- generating an engine load change speed indicative signal representing the speed of a change in load applied to the internal combustion engine;
- comparing said engine load change speed indicative signal with a predetemined reference and generating a comparison result indicative signal when said engine load change indicative signal satisfies a predetermined relationship with said predetermined reference;
- detecting at least one operating condition of the automotive vehicle;
- executing a first routine where a first desired optimum reduction ratio is determined for the detected operating condition of the automotive vehicle
- and an actual reduction ratio of the continuously variable transmission is adjusted toward said first desired optimum reduction ratio;
- repeating said first routine executing step;
- and
- interrupting said first routine executing step after a predetermined condition has been satisfied and executing a second routine where a second desired optimum reduction ratio is determined for the detected operating condition of the automotive vehicle and the actual reduction ratio of the continuously variable transmission is adjusted toward said second desired reduction ratio, said predetermined condition involving generation of said comparison result indicative signal.
An apparatus for controlling a reduction ratio of a continuously variable transmission of an automotive vehicle having a brake pedal and an internal combustion engine with an accelerator pedal, comprising:
- means for detecting an engine load of the internal combustion engine and generating an engine load indicative signal representing the engine load detected;
- means for detecting a parameter indicative of operating condition of the automotive vehicle and generating a parameter indicative signal;
- a control unit receiving inputs including said engine load indicative signal and said parameter indicative signal and generating an output signal, said control unit including a read only memory storing programs performing the steps of computing a change in the engine load indicative signal, comparing said change with a reference and generating a comparison result signal when said change attains a predetermined relationship with said reference;
- executing a first routine where a first desired optimum reduction ratio is determined for said engine load indicative signal and said parameter indicative signal;
- repeating said first routine executing step;
- and interrupting said first routine executing after a predetermined condition has been satisfied involving that said comparison result signal is generated and executing a second routine where a second desired optimum reduction ratio is determined for said engine load indicative signal and said parameter indicative signal;
- and
- means for adjusting the actual reduction ratio of the continuously variable transmission toward a value which agrees with one of said first and second desired optimum reduction ratio in response to said output signal of said control unit.
A method for controlling a reduction ratio of a continuously variable transmission of an automotive vehicle having an internal combustion engine with a throttle valve which opens in degrees, said method comprising the steps of:
- detecting vehicle speed of the automotive vehicle at intervals and generating a vehicle speed indicative signal indicative of the vehicle speed detected;
- detecting opening degree of the throttle valve at intervals and generating a throttle opening degree indicative signal indicative of the opening degree of the throttle valve detected;
- executing a first routine where a first desired reduction ratio is determined based on said vehicle speed indicative signal and said throttle opening degree indicative signal and an actual reduction ratio of the continuously variable transmission is adjusted toward said first desired reduction ratio;
- repeating said first routine executing step;
- computing at intervals of a first predetermined period a difference in said throttle opening degree indicative signal over each of said intervals and generating a difference indicative signal indicative of the difference computed;
- comparing said difference indicative signal with a first reference and generating a comparison result indicative signal when said difference indicative signal attains a first predetermined relationship with said reference;
- and
- interrupting said first routine executing step after a predetermined condition has been satisfied, and executing a second routine where a second desired reduction ratio is determined based on said vehicle speed indicative signal and said throttle opening degree indicative signal and the actual reduction ratio of the continuously variable transmission is adjusted toward said second desired reduction ratio;
- said predetermined condition involving generation of said comparison result indicative signal.
Dependencies are inferred from the claim text.