Hydraulic steering system of engineering machine

Abstract

The invention discloses a hydraulic steering system of an engineering machine and belongs to the technical field of hydraulic systems of engineering machines. The hydraulic steering system comprises a control part and a driving part, the control part comprises a steering gear, and the driving part comprises a steering oil cylinder and a steering pump. An amplification flow valve is serially communicated between the steering pump and the steering oil cylinder, a main valve spool controlling oil flow is arranged in the amplification flow valve, two liquid-control ports of the main valve spool are communicated with two oil outlets of the steering gear through liquid-control reversing valves, liquid-control ports of the liquid-control reversing valves are communicated with the steering pump through a maneuvering reversing valve and a pressure reducing valve. Limiters are arranged on a frame of the engineering machine and correspond to two sides of the maneuvering reversing valve. The hydraulic steering system is simple and reliable in hydraulic loop control manner, no overflow loss of the hydraulic steering system is caused when the engineering machine steers at the limit position of the oil cylinder, hydraulic impact to the frame from the limit position of the oil cylinder during steering is eliminated, energy is saved while shaking after steering is avoided, and comfortableness of the integral engineering machine is improved.

Description

technical field [0001] The invention relates to the technical field of engineering machinery hydraulic systems, in particular to an engineering machinery hydraulic steering system. Background technique [0002] Existing construction machinery hydraulic steering system, such as Figure 5 As shown, it includes a control part and a drive part. The control part includes a steering gear; the drive part includes a steering cylinder 11 and a steering pump 13, and a flow amplification valve 12 is connected in series on the oil circuit between the steering pump 13 and the steering cylinder 11. There is a main valve core 12-1 inside the flow amplifying valve to control the oil displacement, and the two hydraulic control ports 12-1A and 12-1B of the main valve core 12-1 are respectively connected with the two oil outlet ports 15b and 15c of the steering gear , the oil inlet 15a of the steering gear 15 communicates with the oil outlet 13a of the steering pump through the pressure reduci...

AI Technical Summary

Problems solved by technology

[0003] The technical problem to be solved by the present invention is to provide a hydraulic steering system for engineering machinery, which can solve the problem of shaking caused by the large impact force of the oil cylinder on the frame, resulting in loose and easily damaged parts of the engineering machinery and the movement of the oil cylinder to the limit When the position is high, high pressure and large flow overflow will cause energy loss and accelerate oil heating.

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