Patent ID: 6604039
Filing Date: 2003-08-05
Classification: F16H,Y10T

Abstract:
A control device of a toroidal continuously variable transmission for a vehicle, the vehicle comprising an accelerator pedal, and the toroidal continuously variable transmission comprising an input disk, an output disk, a power roller which transmits torque between the input disk and the output disk, a trunnion which supports the power roller free to rotate, the trunnion comprising a trunnion shaft, the power roller varying a gyration angle (&phgr;) according to a displacement (y) of the trunnion in the direction of the trunnion shaft to vary a speed ratio of the input disk and output disk, and an oil pressure actuator which drives the trunnion in the direction of the trunnion shaft, the device comprising:a control valve which supplies oil pressure to the oil pressure actuator; a mechanical feedback mechanism connecting the trunnion and the control valve to feed back the displacement of the trunnion to the control valve; a valve actuator which controls the control valve according to a command value (u); a sensor which detects a rotation speed (&ohgr;co) of the output disk; a sensor which detects a depression amount (APS) of the accelerator pedal; a sensor which detects the gyration angle (&phgr;) of the power roller; a sensor which detects the displacement (y) of the trunnion in the direction of the trunnion shaft; and a programmable controller programmed to: calculate a target control variable (z*) which is a target value of a control variable (z) being an object of control, based on the accelerator pedal depression amount (APS) and the output disk rotation speed (&ohgr;co); calculate a time-variant coefficient (f) representing the relation between the displacement (y) of the trunnion in the direction of the trunnion shaft and a variation rate ({dot over (&phgr;)}) of the gyration angle (&phgr;) of the power roller; calculate a first time differential ({dot over (f)}) which is a time differential of the time-variant coefficient (f); and determine the command value (u) by applying a control gain based on the first time differential ({dot over (f)}).