Method for buffering hydraulic system shock of crawler loader

Abstract

Provided is a method for buffering hydraulic system shock of a crawler loader. According to the method for buffering the hydraulic system shock of the crawler loader, a control unit PLC, a power amplifier and an electro-hydraulic proportional valve are added to the loading hydraulic system. The method for buffering the hydraulic system shock of the crawler loader comprises the steps that (1) when the control unit PLC sends a signal of connecting the electro-hydraulic proportional valve to the power amplifier, oil ways are connected according to a preset numerical value, and the oil ways at the two ends of a two-way hydraulic motor are in a completely connected state or a partially connected state before hydraulic shock occurs; (2) when the control unit PLC controls the electro-hydraulic proportional valve to keep a connected state, the opening quantity of the electro-hydraulic proportional valve is gradually reduced until direction change of a large-inertia load is accomplished after suppression of shock is accomplished; (3) after the direction change of the large-inertia load is accomplished, the control unit PLC controls the electro-hydraulic proportional valve to be closed. The method for buffering the hydraulic system shock of the crawler loader carries out suppression on the hydraulic shock in an initiative mode, and well suppresses the hydraulic shock caused by the excessively fast direction change process of a magnetic exchange valve which has control over the hydraulic motor, and overlarge load inertia.

Description

technical field [0001] The invention relates to a control method for a hydraulic system of a slag scraper, in particular to a buffer method for reducing the hydraulic shock of a large inertia load hydraulic system driven by a hydraulic motor in the hydraulic system of a slag scraper. Background technique [0002] The slag removal machine in the steel plant is driven by a hydraulic control system. The reciprocating movement of the arm is controlled by the operator through the handle. The handle generates a reversing command to control an electromagnetic reversing valve. The electromagnetic reversing valve drives the slag removal by controlling the hydraulic motor. The arm reciprocates. In this system, the slag removal arm and the structure connected to it have a large mass, and the inertial force generated during its movement is the main load of the hydraulic motor, and its impact load is greater than that of the hydraulic motor and the circuit where the hydraulic motor is lo...

AI Technical Summary

Problems solved by technology

[0005] In order to solve this problem, the prior art also adopts the following: one is to install an accumulator on the pipeline connected to the two chambers of the hydraulic motor. When a pressure shock occurs, the accumulator absorbs the hydraulic shock, but the accumulator It is likely to cause excessive delay in action. For manual operation, this delay is inconsistent with people's operating habits; the second is to install a pressure reducing valve on the pipeline connected to the two chambers of the hydraulic hydraulic motor. The decompression valve decompresses to reduce the pressure at both ends of the actuator, but due to the delay in the decompression action of the decompression valve, the effect is limited for fast and severe impacts

[0006] The above-mentioned three existing technologies for reducing impact all have two obvious deficiencies: one is passive execution, that is, only after the pressure shock occurs at both ends of the hydraulic motor, the key components in the three buffer methods, namely the overflow valve, the accumulator, etc. The actuator and the pressure reducing valve start to perform actions, that is, the impact is first, and the action to reduce the impact is later; the second is that the response speed of the key components, the relief valve and the pressure relief valve, is limited. When the hydraulic shock occurs very quickly, the overflow The cushioning effect produced by flow valve and pressure reducing valve must be limited

[0007] In the existing publicly reported literature, CN 102493967 A describes "a hydraulic buffer circuit using a pressure reducing valve plus a throttle valve". This method also has the disadvantages of passive operation and slow response speed of the key component pressure reducing valve

Images