Main oil way pressure control method for preventing clutch from slipping in rapid oil charging stage

Abstract

The invention discloses a main oil way pressure control method for preventing a clutch from slipping in a rapid oil charging stage. The method comprises the following steps that whether a transmissionis about to execute gear shifting operation or not is judged through detection of the state of the transmission, and if the transmission is not about to execute the gear shifting operation, the mainoil way command pressure is kept unchanged; if the transmission is about to execute the gear shifting operation, the main oil way command pressure is increased by deltaP and maintained for deltaT2 according to the current main oil way pressure deltaT1 before gear shifting, and deltaP, deltaT1 and deltaT2 are all increased along with increase of the current main oil way pressure and decreased alongwith decrease of the current main oil way pressure; and after deltaT2 is finished, the main oil way compensation pressure deltaP is removed, and the main oil way command pressure is recovered to theinitial value. After the main oil way command pressure is increased by deltaP, in the gear-shifting rapid oil charging stage, the rapid oil charging control pressure of a gear-shifting electromagneticvalve is compensated, the actual pressure of the main oil way can ensure that a locking clutch is kept locked, the clutch can be prevented from slipping and galloping, the gear-shifting quality is improved, and the service life of the transmission is prolonged.

Description

Technical field [0001] The present invention belongs to the technical field of automatic transmission, and more particularly to a primary oil pressure control method for preventing the clutch slip. Background technique [0002] In the main function of the transmission, shifting control is a very important aspect and its core is. According to the shift, the vehicle is running or stationary, and the shifting is divided into dynamic shifting and static shift, wherein the dynamic shifting process mainly includes a fuel purge phase, a torque phase, a speed phase, and a locking phase. The filling phase is the first stage of the shifting process, but it includes the fast-filled stage and clutch reaches the joint phase, and the fast-filled stage has an important impact on the quality of the shift. [0003] In the fast-filled stage during the shifting process, the characteristics of the solenoid valve are influenced. The rapid increase in the current of the solenoid valve will increase th...

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Problems solved by technology

[0003] In the rapid oil filling stage of the gear shifting process, affected by the characteristics of the solenoid valve, the rapid increase of the solenoid valve current will cause the leakage to increase instantaneously at this stage, and the increase in leakage will cause the pressure of the main oil circuit to decrease instantaneously, resulting in a lock-up clutch. Slippage will cause the motor or engine to run away. Severe runaway will cause ablation of the friction plate of the clutch, which will affect the performance of the clutch and shorten its service life.

[0004] At present, domestic and foreign automatic transmission control methods do not involve the main oil circuit pressure control method to prevent the clutch from slipping during the rapid oil filling stage during the shifting process, so it is impossible to overcome the instantaneous main oil circuit pressure caused by the increased leakage of the solenoid valve. The problem of lowering will lead to clutch slipping and speeding, and even damage the clutch in severe cases

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