Reversing valve

Abstract

The invention provides a hydraulically-driven four-way reversing valve and a hydraulic system thereof. The hydraulically-driven four-way reversing valve comprises a main valve and a pilot valve, the main valve comprises a cylinder body and a piston positioned in the cylinder, four mutually orthogonal connectors are arranged on the cylinder body, and the pilot valve is connected with joints on two sides of the cylinder body of the main valve through a hydraulic oil pipe. Besides, the hydraulically-driven four-way reversing valve is characterized in that the pilot valve controls hydraulic oil to flow into the left side or the right side of the cylinder body of the main valve so as to control the position of the piston in the cylinder body, and communication among the four connectors is controlled according to the position of the piston in the cylinder body. The hydraulically-driven four-way reversing valve is simple in structure, high in reliability, low in leakage rate and capable of effectively reducing reversing noise and can avoid mistaken reversing during power failure.

Description

technical field [0001] The invention relates to a reversing valve used in a compressor unit of a refrigeration system, more precisely, it relates to a reversing valve with simple structure, high reliability, small leakage, which can effectively reduce reversing noise, and can avoid Hydraulically actuated 4-way directional valve for misdirection. Background technique [0002] The structure and operation principle of the piston type four-way reversing valve in the prior art are as follows: figure 1 As shown, the four-way reversing valve includes a main valve body 10, and four connecting pipes connected with the main valve body 10, that is, an exhaust pipe 20, a suction pipe 30, a first heat exchanger pipe 40 and a second heat exchanger Connector 50, end caps 60-1 and 60-2 at both ends of the main valve body 10, guide rod 70 on the end cap 60-2, piston 80 in the main valve body 10, there are two pairs of mutually perpendicular channels on the piston 80, The high-pressure chan...

AI Technical Summary

Problems solved by technology

[0005] Moreover, when the piston-type four-way reversing valve in the above-mentioned prior art is switched, because the pressure difference between the suction and the exhaust is relatively large, and in the process of switching, the four branch pipes will bypass, and the huge airflow sound will be relatively large. loud noise

[0006] In addition, the leakage of the piston type four-way reversing valve in the above-mentioned prior art is relatively large. On the one hand, due to the large suction and exhaust pressure difference, the gap between the piston and the cylinder will cause leakage; on the other hand, the piston Leakage also occurs in the center of the spool

[0007] In addition, in the prior art, if the unit suddenly loses power during operation, and the piston-type four-way reversing valve is in the energized state before the power failure, since the suction and exhaust pressure differences of the system will not be immediately balanced, power failure The rear four-way reversing valve will automatically reversing, which may cause the reversing failure due to insufficient power. The piston of the four-way reversing valve is in the state of four-pipe bypass, which may easily cause the failure of the four-way reversing valve

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