Balanced valve bank of derricking cylinder system

Abstract

The invention relates to a balanced valve bank of a derricking cylinder system. A casting runner, a working port A and a working port B are arranged on a balanced valve body; the balanced valve body is singly connected with one-way valves PF2 and DF1, the one-way valve DF1 is connected with a damper III to form a one-way throttling valve, a control end cover is provided with a control port Px and an unloading port L, the balanced valve body is also connected with a damper IV, an oil tube of the control port Px is connected with a filter screen damper and a damper II, an oil tube of the unloading port L is connected with a damper I; and the dampers I, II and IV as well as the filter screen damper are communicated and matched to form a liquid bridge type control manner. The one-way throttling valve structure effectively solves the problem of loosing of the derricking cylinder produced in China at present. The control end cover is controlled in a liquid bridge manner, which effectively eliminates the phenomenon of joggling of the cylinder because the openness of a balanced valve plug is influenced by pressure impaction. The casting runner reduces the pressure drop and decreases the heating value, therefore, the working efficiency is improved. A one-way valve thread inserting structure is singly inserted into the balanced valve body; and the valve bank can meet the requirements for micromotion, stability and safety in all working conditions.

Description

technical field [0001] The invention relates to a balance valve group, in particular to a balance valve group of a luffing oil cylinder system which is widely applicable to various hydraulic truck cranes in engineering machinery. Background technique [0002] At present, all kinds of hydraulic truck cranes in construction machinery are widely used in bridges and port buildings for assembly operations, but the balance valves of the luffing cylinder systems of existing domestic and some imported truck cranes cannot meet the requirements of micro-movement and stability. Requirements, and when the balance valve is closed, zero leakage cannot be achieved due to material deformation caused by system back pressure and heat generation, resulting in the sinking of the oil cylinder, resulting in a great safety hazard. [0003] Patent No. 200920230848.8 "Balance Valve Group for Large-Load Main Oil Cylinder" only provides a balance valve group that meets the needs of large-flow drilling...

AI Technical Summary

Problems solved by technology

[0002] At present, all kinds of hydraulic truck cranes in construction machinery are widely used in bridges and port buildings for assembly operations, but the balance valves of the luffing cylinder systems of existing domestic and some imported truck cranes cannot meet the requirements of micro-movement and stability. Requirements, and when the balance valve is closed, zero leakage cannot be achieved due to material deformation caused by system back pressure and heat generation, resulting in the sinking of the oil cylinder, resulting in a great safety hazard

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