Centering elastic coupling

Abstract

The invention discloses a centering elastic coupling. The centering elastic coupling comprises a piston rod sleeve provided with a piston rod mounting hole, a middle base and a valve rod sleeve provided with a valve rod mounting hole, wherein the middle base is connected to the piston rod sleeve, an elastic part is arranged between the middle base and the piston rod sleeve, the middle base is meshed with the valve rod sleeve through a spherical bulge and a spherical groove, the middle base is connected to the valve rod sleeve, and meanwhile the piston rod mounting hole and the valve rod mounting hole are coaxial; the sphere centers of the spherical bulge and the spherical groove are located on the central axis of the piston rod mounting hole and the central axis of the valve rod mounting hole, and the elastic part stretches out and draws back in the axial direction of the piston rod mounting hole and the axial direction of the valve rod mounting hole. The spherical centering structure solves the problem that the coaxiality of the piston rod and the valve rod of an actuator is not high, and is convenient to install and safe to operate; and an elastic connecting structure can ensure the normal operation of the actuator and protect the sealing surface of the valve seat.

Description

technical field [0001] The invention relates to a shaft coupling for valves, in particular to a centering elastic shaft coupling structure, which can be applied to the connection between all straight-stroke valves and actuators, and is also suitable for replacing actuators or valves during maintenance. Background technique [0002] At present, for straight-stroke valves, most of the actuators and valves are connected by threaded clamping blocks and fastened with screws. This type of connection structure requires a high degree of coaxiality between the valve and the output shaft of the actuator, and the thread teeth of the clamping block are prone to problems. Damaged, difficult to install problems. And when this connection structure is in use, once the valve core exceeds the limit, the output force will all act on the valve seat, which is not suitable for all valves. [0003] When installing conventional thread clamps, it is extremely difficult to have the actuator piston r...

AI Technical Summary

Problems solved by technology

[0002]At present, for straight-stroke valves, most of the actuators and valves are connected by threaded clamping blocks and fastened with screws. This type of connection structure requires valves and actuators to The coaxiality of the output shaft is relatively high, and there are problems that the thread teeth of the clamping block are easily damaged and the installation is difficult

Moreover, when this connection structure is in use, once the valve core exceeds the limit, the output force will all act on the valve seat, which is not suitable for all valves.

[0003] When installing conventional threaded clamps, it is extremely difficult to have the actuator piston rod coaxial with the valve stem. If it is eccentric, it will cause abnormal operation of the actuator or damage to the valve, etc. Fault

The thread clamp connection method is not suitable for displacement control valves such as flat gate valves and regulating valves, because the over-limiting of the valve core caused by poor actuator accuracy may cause the output force to directly act on the valve seat, resulting in excessive output force and damage seat

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