Apparatus for controlling continuously variable transmission used in vehicle

Claim 1

An apparatus for controlling a continuously variable transmission used in a vehicle having an engine, which controls an actual speed Ne of the engine or a speed ratio of the continuously variable transmission such that the actual engine speed Ne coincides with a desired engine speed No, comprising: a processor means for calculating a desired steady-state speed Ns of said engine for steady running of said vehicle, in relation to at least one running parameter of the vehicle wherein said processor is for: detecting a request of a driver of the vehicle for an abrupt speed change of the vehicle; setting as a first value Nc1 one of the desired steady-state engine speed Ns or the desired engine speed No which has been established immediately before or upon detection of said request for the abrupt speed change; calculating as a second value Nc2 the desired steady-state engine speed Ns corresponding to a present value of one of said at least one running parameter of the vehicle; calculating a product of a constant B and a difference between said second value Nc2 and said first value Nc1, said product being used as a correction value ΔNo; setting a sum of said first value Nc1 and said correction value ΔNo, as said desired engine speed No, while request for the abrupt speed change is detected; and said processor further has means for outputting a signal indicative of the line pressure necessary to control said continuously variable transmission and controlled value means coupled to said processor means and controlled by said outputted signal.

Claim 2

An apparatus for controlling a continuously variable transmission used in a vehicle having an engine, which controls an actual speed Ne of the engine or a speed ratio of the continuously variable transmission such that the actual engine speed Ne coincides with a desired engine speed No, comprising: a processor means for calculating a desired steady-state speed Ns of said engine for steady running of said vehicle, in relation to at least one running parameter of the vehicle wherein said processor is for: detecting a request of a driver of the vehicle for an abrupt speed change of the vehicle; setting as a first value Nc1 one of the desired steady-state engine speed Ns or the desired engine speed No which has been established immediately before or upon detection of said request for the abrupt speed change; calculating as a second value Nc2 the desired steady-state engine speed Ns corresponding to a present value of one of said at least one running parameter of the vehicle; calculating a product of a constant B and a difference between said second value Nc2 and said first value Nc1, said product being used as a correction value ΔNo; setting a sum of said first value Nc1 and said correction value ΔNo, as said desired engine speed No, while request for the abrupt speed change is detected; and said processor further has means for outputting a signal indicative of the line pressure necessary to control said continuously variable transmission and controlled value means coupled to said processor means and controlled by said outputted signal.

Claim 7

A method of controlling a continuously variable transmission of an automotive vehicle having an engine, wherein the transmission is controlled such that an actual Ne of the engine coincides with a desired engine speed No, comprising the steps of: determining a desired steady-state speed Ns of said engine for steady running of said vehicle, based on at least one running parameter of the vehicle, and according to a predetermined relationship between said desired steady-state engine speed Ns and said at least one running parameter; detecting an abrupt increase in a currently required output of said engine; setting as a first value Nc1 one of the desired steadystate engine speed Ns or the desired engine speed No which has been established immediately before or upon detection of said abrupt increase in the currently required output of the engine; setting as a second value Nc2 the desired steady-state engine speed Ns corresponding to a present value of one of said at least one running parameter of the vehicle; calculating a correction value ΔNo by calculating a product of a constant B and a difference Nc2-Nc1 between said first and second values Nc2 and Nc1; and controlling said continuously variable transmission by using a sum of said first value Nc1 and said correction value ΔNo as said desired engine speed No while said abrupt increase in the currently required output of the engine is detected as the controlling signal.

Claim 8

A method of controlling a continuously variable transmission of an automotive vehicle having an engine, wherein the transmission is controlled such that an actual Ne of the engine coincides with a desired engine speed No, comprising the steps of: determining a desired steady-state speed Ns of said engine for steady running of said vehicle, based on at least one running parameter of the vehicle, and according to a predetermined relationship between said desired steady-state engine speed Ns and said at least one running parameter; detecting an abrupt increase in a currently required output of said engine; setting as a first value Nc1 one of the desired steadystate engine speed Ns or the desired engine speed No which has been established immediately before or upon detection of said abrupt increase in the currently required output of the engine; setting as a second value Nc2 the desired steady-state engine speed Ns corresponding to a present value of one of said at least one running parameter of the vehicle; calculating a correction value ΔNo by calculating a product of a constant B and a difference Nc2-Nc1 between said first and second values Nc2 and Nc1; and controlling said continuously variable transmission by using a sum of said first value Nc1 and said correction value ΔNo as said desired engine speed No while said abrupt increase in the currently required output of the engine is detected as the controlling signal.