A Pilot Proportional Control Switch Valve

Abstract

The invention belongs to the field of fluid drive and control and particularly relates to a pilot proportional control type switch valve. The pilot proportional control type switch valve comprises a valve body and a main valve element. One end of the valve body is provided with a driving device. A first adjustment cavity is formed between the driving device and the main valve element. The other end of the main valve element is provided with a second adjustment cavity communicating with a high-pressure oil inlet. The main valve element is internally provided with a pilot valve element. The pilot valve element is driven to change the hydraulic pressure of the first adjustment cavity to form the hydraulic pressure difference so as to move the main valve element. The pilot proportional controltype switch valve provided by the invention has the following advantages that main valve element is hydraulically driven rather than direct electromagnetic driven, and driving force is greatly increased; the pilot valve element is designed in the main valve element, and the size is greatly reduced; the pilot valve element is designed for controlling the pressure of control cavities at the two ends of a main valve, the flow required for guide control is quite small, and thus, the driving force for driving the pilot valve element is quite small; the size of an electromagnetic driving device isfurther reduced, and the purpose of energy conservation and emission reduction are achieved.

Description

technical field [0001] The invention belongs to the field of fluid transmission and control, in particular to a pilot proportional control switch valve. Background technique [0002] Fluid control valves, especially hydraulic valves, play the role of controlling flow, pressure and switching oil circuits. For example, the electromagnetic switching valve plays the role of controlling the flow and switching the oil circuit; the electromagnetic switching valve is divided into: single-stage valve (direct acting valve) and two-stage valve (pilot control valve) according to the flow capacity. In the industry standard, single-stage valves (direct-acting valves) are divided into 6 channels and 10 channels; two-stage valves (pilot control valves) are divided into 16, 25, 32... channels (the larger the number The larger the valve volume, the greater the flow capacity). [0003] The fluid switching control valve used for small flow is generally in the form of a single-stage direct-act...

AI Technical Summary

Problems solved by technology

For fluid control valves with medium and large flow rates, since the hydraulic force acting on the valve core is too large when the valve core is opened, it is still impossible to overcome the hydraulic force to push the valve core simply by increasing the volume of the electromagnetic drive device.

So the current technology is: use a small electromagnetic switch valve (usually 6-way through) as the pilot stage, control the pressure of the left and right chambers of the valve core, and realize the hydraulic power to push the valve core, which solves the problem of large flow down-changing However, this technology not only increases the volume of the switch valve, but also increases the cost. The superposition of the two valves also increases the complexity of the valve and reduces the reliability of the valve.

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