A Flow Type Balance Valve

Abstract

The invention discloses a flow type balance valve. The flow type balance valve comprises a valve body, a main valve core, a check valve core, a guide valve sleeve assembly, a damping check valve, a first elastic part and a second elastic part, wherein the guide valve sleeve assembly fixedly sleeves the valve body in an opposite direction, the main valve core and the check valve core are axially arranged in the guide valve sleeve assembly in a sliding mode in the opposite direction, an X oil port is formed in the valve body, a V oil port and a C oil port are formed in the guide valve sleeve assembly, and the C oil port is communicated with an inner cavity of the check valve core and a flow channel in the main valve core; a plurality of throttle through holes are radially formed in the guide valve sleeve assembly near the V oil port; when oil enters the V oil port, the check valve core is opened, and the V oil port is communicated with the C oil port; when oil enters the X oil port, the main valve core is pushed to compress the first elastic part along the axial direction, the throttle through holes of the guide valve sleeve assembly are exposed, and the flow area is gradually increased. The flow type balance valve has the advantages of simplicity in processing, smoothness in flowing and reliability in use, and the load lowering speed can be accurately controlled.

Description

technical field [0001] The invention relates to the technical field of control valves, in particular to a flow-type balance valve capable of accurately and stably controlling the speed of dropping a load. Background technique [0002] In modern construction machinery, construction machinery and other mechanical equipment, a large number of lifting hydraulic circuits are used. Among them, the balance valve is the key hydraulic component that controls the work of the hydraulic cylinder in the lifting circuit. The performance of the balance valve directly affects the performance of the main engine. The existing hydraulic balance valve generally has such a shortcoming: when the load is lowered, due to the characteristics of sudden changes in the flow area of ​​the valve port of the hydraulic balance valve, it will cause low-frequency jitter and impact on the load, resulting in system instability and affecting the overall performance. Machine safety and reliability. [0003] The...

AI Technical Summary

Problems solved by technology

The existing hydraulic balance valve generally has such a shortcoming: when the load is lowered, due to the characteristics of sudden changes in the flow area of ​​the valve port of the hydraulic balance valve, it will cause low-frequency jitter and impact on the load, resulting in system instability and affecting the overall performance. Machine safety and reliability

[0004] (1) When the load is lowered and the load is raised, it passes through the same valve port, which will produce a throttling effect, but in practice, when the load rises, the throttling effect is not needed, which seriously affects the efficiency of the operation; in order to solve this problem, it is necessary to connect a valve in parallel. One-way valve, virtually increases the cost;

[0005] (2) After milling grooves and drilling small holes and inclined holes on the cone valve core, the rigidity of the valve core is greatly reduced. When the control load is lowered, it must bear a large pressure difference and rapid liquid flow impact, and the heat treatment is not good. If not, the spool is easily broken and the reliability is greatly reduced;

[0006] (3) The milling groove on the cone valve core is complicated to process and low in efficiency, so the production cost is high;

[0007] (4) Although the flow area of ​​the spool changes gradually, when the pilot pressure suddenly rises, the poppet spool will also move rapidly, causing a large sudden change in the flow rate and causing jitter, so the movement of the spool lacks damping link

By setting a damping hole at the control port, although the opening speed of the valve core will be slowed down, the speed when the valve core is closed will also be reduced, causing the sliding distance to be too large when the load stops

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