Patent ID: 6139471
Filing Date: 2000-10-31
Classification: B60W,F16H,Y10T

Abstract:
A control system for an automatic transmission, comprising:a fluid transmission unit connected to an engine;a clutch applied when a forward running range is selected, for transmitting the rotation of said fluid transmission unit to a speed change unit;a hydraulic servo for applying said clutch responsive to feed of an oil pressure;output RPM detecting means for detecting output RPM of said fluid transmission unit;oil pressure generating means for generating the oil pressure fed to said hydraulic servo; anda control unit, including:a memory containing a preset range for said output RPM, a maximum RPM in said preset range and a preset value;booster means for raising said oil pressure according to preset characteristics stored in said memory;change rate detecting means for detecting RPM change rate of the output RPM, within said preset range for said output RPM, at the time of application of said clutch, said change rate detecting means detecting said RPM change rate only when the output RPM at the time of start of engagement of said clutch is higher by said preset value than said maximum RPM in said preset range for said output RPM; andcorrection means for correcting said preset characteristics on the basis of a comparison of the RPM change rate, as detected by said change rate detecting means, with a reference RPM change rate.