Excavator and priority control loop of excavator

Abstract

The invention provides an excavator and a priority control loop of the excavator. The priority control loop of the excavator comprises a main pump, a swing arm lifting oil way and a swing action oil way, wherein the swing arm lifting oil way and the swing action oil way are connected in parallel. The swing arm lifting oil way comprises a swing arm reversing valve and a swing arm drive oil cylinder, wherein the swing arm reversing valve and the swing arm drive oil cylinder are connected with the main pump in series. The swing action oil way comprises a prior valve, a swing reversing valve and a swing motor, wherein the prior valve, the swing reversing valve and the swing motor are connected with the main pump in series. The swing action oil way further comprises a buffering valve and a manual pilot valve. A working oil port of the manual pilot valve is simultaneously communicated with an oil inlet of the buffering valve and a control end of the swing arm reversing valve. An oil outlet of the buffering valve is communicated with a control end of the prior valve. The prior valve is in a circulating state when the control end of the prior valve is under no pressure, and is in a throttling state when the control end of the prior valve is under pressure. Due to the facts that the manual pilot valve is used in the priority control loop of the excavator for outputting voltage so as to control the prior valve, and a proportional valve or a controller does not need to be added, cost is effectively reduced, stability is high, operation is gentle, and the problem of abrupt acceleration caused by an abrupt change of flow is solved.

Description

technical field [0001] The invention relates to the field of engineering machinery, in particular to an excavator and a priority control circuit thereof. Background technique [0002] At present, the excavator industry uses a variety of channels to solve the problem of uncoordinated hydraulic system compound actions, mainly through various means to solve the problem of uneven flow distribution of the main valve. The piston adopts confluence regeneration function and other methods to ensure the reasonable flow distribution and improve the coordination performance of the excavator operation. [0003] figure 1 It is a schematic diagram of an existing hydraulic circuit that controls the priority action of boom lifting or turning. As shown in the figure, it outputs a pressure signal through the electromagnetic proportional pressure reducing valve 10, thereby controlling the opening of the priority valve 3 to ensure that the boom During the compound action of lifting and turning...

AI Technical Summary

Problems solved by technology

[0006] In view of this, the present invention aims to propose an excavator and its priority control loop to solve the problems of poor control stability and poor operation softness caused by sudden flow changes

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