Air control valve installed on pneumatic actuator

Abstract

The invention relates to an air control valve mounted in a pneumatic actuator. The air control valve comprises a valve body, wherein a switching cavity as well as a first channel, a second channel and a third channel which are respectively communicated with the switching cavity, a first switching hole communicated with the switching cavity is formed in one end of the first channel, the other end of the first channel is an air source mounting hole, a communicating hole communicated with the switching cavity is formed in one end of the second channel, the other end of the second channel is a non-spring cavity mounting hole, a second switching hole communicated with the switching cavity is formed in one end of the third channel, the other end of the third channel is a spring cavity mounting hole, a main valve element moving according to air pressure is arranged in the switching cavity, an exhaust channel communicating the second channel with the outside is arranged in the valve body, and a unidirectional circulation assembly only allowing gas to flow to the outside from the second channel is arranged in the exhaust channel. By adopting the scheme, the air control valve provided by the invention has the advantages that air suction from the outside due to a spring cavity is avoided and internal components can not be corroded.

Description

technical field [0001] The invention relates to a valve, in particular to an air valve installed in a pneumatic actuator. Background technique [0002] Spring return type pneumatic actuator, one side of the piston is equipped with a spring, the piston divides the cylinder into a cavity without spring and a cavity with spring, the cavity with spring is directly connected to the atmosphere, the cavity without spring is connected to the control valve, the cylinder is controlled by the air source and the spring Reset realizes the opening and closing of the actuator. [0003] The spring return pneumatic actuator can be quickly reset by using it in a more important station, such as when the gas is cut off and the power is cut off. Therefore, the actuator needs to have good stability and fast reset speed. [0004] When there is no spring chamber for air intake, the piston compresses the spring, the volume of the spring chamber decreases, and the gas (atmospheric pressure air) is d...

AI Technical Summary

Problems solved by technology

Therefore, when the spring return pneumatic actuator works under certain working conditions, such as the environment containing corrosive gas, dust environment, salt spray environment, etc., the cavity in the spring cavity and the spring are still vulnerable to corrosion even though they have undergone anti-corrosion treatment. Corrosion, especially after the spring corrosion fails, directly affects the opening and closing of the actuator

Images