Manual and electric proportional control load-sensitive multi-way valve

Abstract

The invention discloses a manual and electric proportional control load sensitive multi-way valve, which comprises an oil inlet valve body, more than two electric proportional reversing valves, and an oil return valve body. The pilot pressure reducing valve is connected with the pilot oil inlet port of each electric proportional directional control valve, and the oil return valve body is also equipped with a system pilot oil return port connected with each pilot oil return port. Each electro-proportional directional valve is also equipped with an internal load feedback oil circuit and a shuttle valve, one of which is connected to the load feedback oil port, and the internal load of each electro-proportional directional valve The feedback oil circuit is connected with the inner cavity of the valve seat of each shuttle valve, and the inner cavity on both sides of the valve core in each shuttle valve seat is respectively connected with the inner cavity of the two working oil ports of the respective electric proportional directional control valve and the adjacent electric proportional switch at the rear. It is connected to the load feedback oil circuit in the valve. The invention has the advantages of relatively simple structure, convenient manufacture and low cost, excellent stability, coordination and reliability of multi-executing agencies, high control precision and long-term normal operation of the system.

Description

technical field [0001] The invention relates to a multi-way valve, in particular to a load-sensitive multi-way valve capable of realizing manual and electric proportional control. Background technique [0002] At present, it is widely used in cranes, concrete pump trucks and other construction machinery and multi-way valves of medium and large-scale mechanical equipment with multiple mechanisms. Load pressure follow-up control system. Hydraulic load sensing technology can control the work of one or more actuators, and the fine-tuning performance is very good; on the premise of satisfying various control functions of the machine, it reduces pressure loss, improves efficiency, and has better economy; but the existing For load sensitive multi-way valves, it is necessary to set up more complex LS load pressure feedback oil circuit and control components in each directional valve. It is easy to influence each other during compound actions, the working conditions are difficult t...

AI Technical Summary

Problems solved by technology

Hydraulic load sensing technology can control the work of one or more actuators, and the fine-tuning performance is very good; on the premise of satisfying various control functions of the machine, it reduces pressure loss, improves efficiency, and has better economy; but the existing For load sensitive multi-way valves, it is necessary to set up more complex LS load pressure feedback oil circuit and control components in each directional valve. It is easy to interact with each other during compound actions, and the working conditions are difficult to stabilize. It is difficult to guarantee the stability, coordination, reliability and control accuracy of multiple actuators, and the normal operation of the system is affected.

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