Combined type automobile hydraulic power-assisted steering protection system

Abstract

The invention discloses a combined type automobile hydraulic power-assisted steering protection system which comprises an oil tank, a booster pump, a steering valve and a steering power cylinder, wherein the oil tank is communicated with the booster pump, the output end of the booster pump is communicated with the steering valve through an oil inlet pipe, the steering valve is further communicated with the oil tank through an oil return pipe, the oil inlet pipe is communicated with the oil return pipe through a pressure relief pipe, and an overflow valve is arranged on the pressure relief pipe; the oil inlet pipe is further communicated with the oil tank through a standby pipe, and a one-way valve is arranged on the standby pipe and communicated in the direction towards the oil inlet pipe. According to the combined type automobile hydraulic power-assisted steering protection system adopting the structure, the overflow valve is arranged, and the system is used for protecting a power-assisted steering hydraulic system from being damaged in the using process of an automobile under the conditions that steering wheels are in a limit state, a steering wheel keeps applying force in the same direction and an engine keeps running at a high speed; and meanwhile, when application scenes such as damage of a hydraulic pump or blockage of an oil inlet pipeline occur in the power-assisted steering hydraulic system, the dead stagnation condition during steering of driving wheels is eliminated by utilizing the one-way valve.

Description

technical field [0001] The invention relates to an automobile component technology, in particular to a composite automobile hydraulic steering power-assisted protection system. Background technique [0002] At present, in the design of automobile steering system, the hydraulic system is widely used to realize the power steering function, that is, the hydraulic pump (boost pump) drives the hydraulic oil to provide power, and the hydraulic pump is directly driven by the engine. Specifically, the hydraulic booster mechanism inside the automobile steering gear is a hydraulic cylinder structure, and the piston in the hydraulic cylinder is connected to the steering wheel of the automobile through a connecting rod mechanism. When the automobile needs to turn, the valve group of the hydraulic system is controlled to turn on the pressure The oil enters one side of the piston chamber in the hydraulic cylinder, and the other side is connected to the oil tank of the hydraulic system at ...

AI Technical Summary

Problems solved by technology

[0003] Under this structure, when the steering wheel of the car is at the steering limit position and keeps applying force to the steering wheel in the same direction, the hydraulic oil inlet path on the side of the steering gear is closed, but the hydraulic pump is still running normally because it is directly driven by the car engine. When the engine is running at high speed, the booster pump rotor is also running at high speed. At this time, because the oil inlet of the steering gear is closed, the hydraulic oil cannot form a circulating state in the hydraulic system pipeline, resulting in the hydraulic oil in the booster pump cavity being in the booster pump rotor impeller. Driven by the drive, a high-speed microcirculation is formed in the pump casing, and the hydraulic oil rubs against the inner wall of the pump at a high speed, and the oil temperature rises rapidly, resulting in an excessively high temperature of the hydraulic oil. However, since the sealing surface of the pump casing is made of rubber, it cannot withstand If the temperature is too high, the sealing material is damaged, the hydraulic booster pump leaks and other damages occur immediately, and the booster system fails

[0004] When the steering assist hydraulic system cannot provide steering assist in the application scenario, the car still has the ability to turn. At this time, because the hydraulic system cannot provide assist, the driver needs to turn the steering wheel with greater force, and directly drive the piston in the steering machine through the connecting mechanism. However, when the hydraulic pump of the automobile hydraulic power assist system is damaged or the oil inlet pipeline of the hydraulic system is blocked, the hydraulic oil cannot be replenished into the piston cavity of the steering gear, and the piston cylinder in the steering gear needs to be filled with oil. The cavity will form a vacuum state. Due to the effect of atmospheric pressure, the piston will not move, and the wheels will appear deadlocked during the steering operation, and the vehicle will lose its steering ability.

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