Speed ratio adjusting device of continuously variable transmission of hydraulic machinery

Abstract

The invention discloses a speed ratio adjusting device of a continuously variable transmission of hydraulic machinery. The device comprises a speed ratio stepless adjusting unit and two movable conical disc pressure adjusting units; the speed ratio stepless adjusting unit comprises two movable conical discs; the two movable conical discs respectively sleeve a power input shaft and a power output shaft, and are respectively connected with a driving wheel hydraulic cylinder and a driven wheel hydraulic cylinder; oil holes on the power input shaft and the power output shaft respectively communicate with the driving wheel hydraulic cylinder and the driven wheel hydraulic cylinder; the movable conical disc pressure adjusting units comprise motors; the motors are connected with plunger pumps; oil inlets and oil outlets of the plunger pumps are respectively connected with oil tanks and P ports of high-speed switching valves; and A ports of the high-speed switching valves of the two movable conical disc pressure adjusting units are respectively connected with the oil holes on the power input shaft and the power output shaft. The device has the advantages of simple structure, stable pressure adjustment, high adjusting reliability and precision of the speed ratio and the clamping force and short acceleration time, and achieves self-protection capacity of the continuously variable transmission.

Description

technical field [0001] The invention relates to a speed ratio adjusting device of a hydraulic mechanical stepless transmission. Background technique [0002] Continuously variable transmission (CVT) is an ideal automobile transmission, it has a continuously variable speed ratio, can control the automobile engine to always run in the best working area, can improve the fuel economy and power performance of the automobile, and reduce the Due to the advantages of the shifting impact and the improvement of the driver's driving comfort, the CVT has been paid more and more attention, and the research work on the metal belt CVT is the most. In the continuously variable transmission, the CVT speed ratio adjustment is the key technology of the hydromechanical continuously variable transmission. To achieve the best match, improve vehicle fuel economy, etc. [0003] At present, almost all CVTs on the market use electro-hydraulic control CVT. The hydraulic system for speed ratio adjust...

AI Technical Summary

Problems solved by technology

The two can only realize the continuous change of the speed ratio of the continuously variable transmission. The speed ratio control precision of the former is higher than that of the latter, and the clamping force control precision of the latter is higher than the former, but their speed ratio control precision and clamping force control precision are both low. , long acceleration time, lack of self-protection and speed ratio self-maintaining ability of continuously variable transmission, which limits the power and economic performance of the vehicle

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