Clutch Oil Filling Control Method for Dual Clutch Automatic Transmission

Abstract

The invention provides a method for controlling oil filling of clutches of an automatic double-clutch gearbox. The method comprises the step of filling oil in advance, wherein the clutches are filled with the oil in advance after pre-shifting of a target gear is finished, and the preset time is maintained; the step of filling the oil for the second time, wherein the clutches of the target gear are filled with the oil for the second time until linkage point pressure is reached; the step of maintaining the linkage point pressure, wherein the linkage point pressure of the clutches of the target gear is maintained until torque is alternated. In the step of filling the oil in advance, the current oil temperature of the gearbox is measured, and filling the oil in advance is carried out according to the current oil temperature of the gearbox. The temperature change of the oil in the gearbox is utilized for controlling the clutch oil filling process, and therefore timeliness and smoothness of clutch motions in the shifting process can be improved, and the fault rate of the automatic wet type double-clutch gearbox can be lowered.

Description

technical field [0001] The invention relates to the field of dual-clutch automatic transmission control. Background technique [0002] The dual-clutch automatic transmission transmission device is connected to two input shafts through two clutches, and realizes torque conversion and output through different output shafts, thereby transmitting engine power. According to the different forms of the clutch, the dual-clutch gearbox is divided into a dry dual-clutch automatic gearbox and a wet dual-clutch gearbox. Dry dual-clutch automatic transmissions usually use motor control to control clutch engagement and disengagement; wet dual-clutch automatic transmissions usually use hydraulic methods to control clutch engagement and disengagement. [0003] In the Chinese invention patent application with application number: 201210553278.2, application date: 2012-12-19, and invention name: "Shift control method for wet dual clutches", two clutches are realized through three steps of pre...

AI Technical Summary

Problems solved by technology

On the one hand, in the prior art, the pre-charge pressure value calibrated at the factory stage is still used as the initial value before shifting gears, and then the pre-charge pressure value is adjusted and corrected in reverse according to the output torque during the second oil charge stage It is obviously too late, which is not conducive to the timely and smooth shifting

On the other hand, in the second oil filling stage, due to the change of oil temperature during the shifting process, the clutch oil filling time and the maximum oil filling pressure maintenance time also need to be changed for pressure compensation, otherwise it will cause the second oil filling process to fail. stable

On the other hand, after the oil filling of the clutch reaches the linkage point pressure, in order to ensure that the clutch oil pressure is kept near the linkage point pressure for a period of time before the torque is alternated, there will also be oil temperature changes during this period. Will cause pressure fluctuations at linkage points

In the above three stages, if the pressure compensation problem caused by oil temperature changes is not considered, it will affect the timeliness and smoothness of shifting, resulting in a very obvious sense of frustration during the shifting process, and the engine speed will increase by itself or cannot There are many faults such as acceleration, fault lights flashing, only certain gears can be driven, and abnormal noise when shifting gears.

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