Load-sensitive multi-way valve with double-pump confluence function

Abstract

The utility model discloses a load-sensitive multi-way valve with a double-pump confluence function, and relates to the technical field of hydraulic pressure of straight-arm lorry-mounted cranes. The load-sensitive multi-way valve comprises a first pump oil inlet control unit, a proportional reversing valve working unit, a confluence control unit, a rotation reversing unit and a second pump oil inlet control unit. The first pump oil inlet control unit is connected with a first quantitative oil pump and supplies oil to the proportional reversing valve working unit, the second pump oil inlet control unit is connected with a second quantitative oil pump and supplies oil to the rotation reversing unit, and when the rotation reversing unit does not work, the second quantitative oil pump and the first quantitative oil pump are converged through a one-way valve and a hydraulic control reversing valve of the converging control unit; the two pumps simultaneously supply oil to the proportional reversing valve working unit, so that the working efficiency is improved; and when the rotation reversing unit works, the hydraulic control reversing valve of the confluence control unit cuts off a confluence channel of the second quantitative oil pump and the first quantitative oil pump, the second quantitative oil pump independently supplies oil to the rotation reversing unit, rotation action flow matching is achieved, and energy consumption and system temperature rise are reduced.

Description

technical field [0001] The invention relates to the technical field of straight-arm truck-mounted crane hydraulics, in particular to a load-sensing multi-way valve with a double-pump confluence function. Background technique [0002] The straight-arm truck-mounted crane is a multi-purpose machine installed on the chassis of a car that can load and unload heavy objects within a certain range. It is fast, flexible, convenient, and integrated with hoisting and transportation. It is widely used in equipment loading and unloading, landscaping, Municipal construction and other hoisting and transportation fields. In recent years, with the development of the market and technology, the concept of high efficiency, fast energy saving and other times is becoming the technical development trend of truck-mounted cranes. [0003] The main operating actions of the straight arm truck-mounted crane include telescopic, hoisting, luffing and slewing. The multi-way valve on the car is the core ...

AI Technical Summary

Problems solved by technology

At present, the mainstream of straight-arm truck-mounted cranes adopts single oil pump oil supply and proportional multi-way valve control system. Due to the main operation actions of straight-arm cranes, the requirements for system flow and pressure vary greatly. The existing single-pump oil supply system It is difficult to meet the requirements of high efficiency, low energy consumption and precise control. At the same time, due to the limitation of the dynamic characteristics of the chassis engine, the large-displacement single-pump system is also difficult to solve the problem of engine suffocation and flameout under high load pressure.

[0004] Utility Model Patent Application No. 202010424973.3 discloses a confluence proportional multi-way reversing valve and working method for straight-arm truck-mounted cranes. The multi-way valve device and working method in which the first oil pump and the second oil pump merge, and the other states do not merge, can only realize the double pump merge during the hoisting action, and the pressure on both sides where the first pump and the second pump are located should be The same, otherwise, when the set pressure on the side of the rotary joint is low, the pressure of the LS oil circuit on the side of the hoisting joint in the merged state is pulled down by the pressure on the side of the rotary joint, causing the pressure of the entire system to fail to rise in the merged state; When the pressure settings on the Yanglian side and the rotary side are both the same and high enough, the engine of the engine chassis may hold pressure and stall due to insufficient output power or torque

[0005] Utility model patent application number 2017109447089.6 discloses a multi-way valve reversing device for a truck-mounted crane. The object involved is a switch-type multi-way valve instead of the proportional core multi-way valve of the present invention. Poor control, flow matching, and high energy consumption can no longer meet the technical development requirements of truck-mounted crane products at this stage

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