Limp home oil system for CVT with wet clutch

Abstract

The invention discloses a limp home oil circuit system of a continuously variable transmission with a wet clutch. The limp home oil circuit system comprises a hydraulic oil pump, a manual valve, a first electromagnetic valve, a second electromagnetic valve, a third electromagnetic valve, a fourth electromagnetic valve, a first mechanical valve, a second mechanical valve, a third mechanical valve, a fourth mechanical valve, a reverse gear brake, a forward gear clutch, a master cylinder, a slave cylinder, a switch valve and a fifth mechanical valve. When a TCU (transmission control unit) operates normally, the switch valve is in a powered operating state, and a control oil circuit of the fourth mechanical valve is controlled by the second electromagnetic valve. When all driving stages of the TCU are switched off, the switch valve is in a reset state under the action of a spring, and the control oil circuit of the fourth mechanical valve is controlled by the fifth mechanical valve. When the TCU can not operate normally, and all the driving stages are switched off, a handle is shifted to a position D, and an accelerator pedal is pedaled; when the rotational speed of an engine reaches a certain threshold value, operation in a forward gear is realized, the handle is shifted to a position R, and the accelerator pedal is pedaled; when the rotational speed of the engine reaches a certain threshold value, reverse driving can be realized.

Description

technical field [0001] The invention is related to the hydraulic control system of the CVT of the automobile continuously variable transmission, and specifically relates to the hydraulic system of the wet clutch type CVT to realize the limp home under the emergency situation when all the drives of the transmission electronic control unit TCU are all closed. Background technique [0002] At present, the mainstream transmissions on the market include manual transmission (MT), automatic mechanical transmission (AMT), dual clutch transmission (DCT), continuously variable transmission (CVT) and hydraulic automatic transmission (AT). Among them, the continuously variable transmission CVT has the advantages of smooth shifting and obvious fuel-saving effect in urban working conditions, which is more suitable for the road conditions in China, so the loading rate of this kind of transmission in my country is getting higher and higher. [0003] According to the form of driving system, t...

AI Technical Summary

Problems solved by technology

[0006] However, when a key sensor of the vehicle fails or other mechanical failures cause all drive stages of the transmission electronic control unit TCU to be shut down, the conventional CVT forward clutch and reverse brake with wet clutches will disengage, The power cannot be transmitted, therefore, in this case, the faulty vehicle can only stop driving, and cannot return to the repair shop by its own power, which brings a lot of inconvenience to the user

Images