Variable-cycle upshift process control method for multi-gear wire control automatic transmission

Abstract

The invention discloses a variable-cycle upshift process control method for a multi-gear wire control automatic transmission. The method comprises the following steps: judging whether the first gear is shifted to the second gear, the second gear is shifted to the third gear and the third gear is shifted to the fourth gear by detecting a D-gear switch signal, a vehicle speed signal v of a vehicle speed sensor and an opening signal alpha of an accelerator pedal position sensor by an electrical control unit, and controlling the power-on current of an electromagnetic clutch in each upshift process; taking the process of shifting the second gear to the third gear as an example, by a variable cycle function T(v), controlling the power-on current of a third-gear electromagnetic clutch according to a power-on current function I3b(t) (I3b(t)={I3, t is not less than 0 and not more than T[delta]; kI3+I3(1-k)(t-T[delta])/(T23-T[delta]), t is more than T[delta] and not more than T23}) of the third-gear electromagnetic clutch, and controlling the power-on current of a second-gear electromagnetic clutch according to a power-on current function I2b(t) (I2b(t)={I2, t is not less than 0 and not more than IT[delta]; 0, t is more than IT[delta] and not more than T23}) of the second-gear electromagnetic clutch by the electrical control unit, so that the control on the upshift process of the wire control automatic transmission is finished. According to the method, the interruption of input power of an engine in the upshift process and the impact of shifting can be avoided, and the upshift process of the wire control automatic transmission is stable.

Description

technical field [0001] The invention relates to a control method of an automatic transmission, more precisely, a control method for a variable-period upshift process of a multi-speed wire-controlled automatic transmission. Background technique [0002] Automatic transmissions are widely used in various vehicles such as automobiles, electric vehicles, and construction machinery. The existing automatic transmissions mainly include hydromechanical automatic transmission (AT), metal belt continuously variable automatic transmission (CVT), mechanical automatic transmission (AMT) and dual clutch automatic transmission (DCT). [0003] The above-mentioned four types of automatic transmissions all adopt electronically controlled hydraulic servo devices to realize the control of the shifting process, which has complex structure, high cost and increased control difficulty and complexity. In particular, the executive mechanism of DCT includes: oil supply mechanism composed of hydraulic...

AI Technical Summary

Problems solved by technology

These hydraulic control mechanisms make the overall structure of the trans...

Images