Amplitude variation gravity drop crane load-sensitive multipath reversing valve

Abstract

Disclosed is an amplitude variation gravity drop crane load-sensitive multipath reversing valve. A main winch reversing piece, an auxiliary winch reversing valve piece, an amplitude variation reversing valve piece and a suspension arm telescopic reversing valve piece are respectively provided with a valve rear compensation piston, a balance valve is arranged between the amplitude variation reversing valve piece and an amplitude variation oil cylinder, an opening A2 of the amplitude variation reversing valve piece is connected with a check valve port V2 of the balance valve, an opening B2 of the amplitude variation reversing valve piece is connected with an external control opening P of the balance valve, an opening V1 of the balance valve is connected with a large cavity of the amplitude variation oil cylinder, and an opening T of the balance valve is connected with a small cavity and an oil tank of the amplitude variation oil cylinder. The valve has the advantages that synchronous control of the displacement of an amplitude variation reversing valve rod and the displacement of an opening of a valve rod of the amplitude variation balance valve can be achieved, the stable drop of the amplitude variation can be achieved, shaking of an execution mechanism in the dropping process is removed, a diverter and confluence valve block of the crane load-sensitive multipath reversing valve can be removed, and therefore the confluence off-and-on impact is solved, and the cost of the load-sensitive multipath reversing valve is reduced.

Description

technical field [0001] The invention relates to a flow distribution device for a quantitative load-sensitive hydraulic system of construction machinery, in particular to a load-sensitive multi-way reversing valve for a load-bearing oil cylinder of construction machinery such as a crane that relies on its own weight to descend with variable amplitude and gravity. Background technique [0002] Quantitative load-sensing hydraulic systems are widely used in construction machinery such as loaders and cranes due to energy saving and low cost. Load-sensing multi-way directional valves are the core hydraulic components of quantitative load-sensing hydraulic systems. Considering energy and environmental protection issues, the requirements for energy saving and emission reduction of construction machinery are getting higher and higher. For this purpose, energy-saving technologies are widely used in the hydraulic system of construction machinery, and the most widely used is to rely on ...

AI Technical Summary

Problems solved by technology

[0003] 1. The amplitude of the truck crane adopts the power drop method, and the opening of the balance valve is controlled by the pressure of the small cavity of the oil cylinder. The disadvantages of this method are: (1) the opening of the balance valve is self-controlled, which may easily cause the vibration of the amplitude; (2) the amplitude During the falling process, most of the flow of the double pump will overflow through the three-way pressure compensator, resulting in energy loss

Aiming at this energy loss, the dual-pump separation and confluence system is usually adopted to realize single-pump oil supply during the amplitude descending process. However, this solution introduces a dual-pump separation and confluence block, which complicates the system and brings confluence and flow interruption. When the system flow and pressure shock;

[0004] 2. For the manually controlled quantitative pump load-sensitive multi-way reversing valve, it is impossible to give an external control signal to the balance valve, so the power drop must be used for the amplitude drop, which causes the energy loss of the system

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