Single acting actuator

Single acting actuator

Selection of single acting actuator take SR series pneumatic actuator as an example. In the application of spring return, the output torque is obtained in two different operation processes. According to the stroke position, each operation produces two different torque values. The output torque of the spring return actuator is obtained by multiplying the force (air pressure or spring force) by the force arm. The first condition is that the output torque is obtained after the air pressure enters the middle cavity and compresses the spring, which is called "air stroke output torque". In this case, the air source pressure forces the piston to turn from 0 degree to 90 degree position, and the spring compression produces reaction force, The torque gradually decreases from the maximum value at the starting point to the second condition: the output torque is obtained by the spring restoring force acting on the piston when the cavity loses air, which is called "spring stroke output torque". In this case, due to the extension of the spring, the output torque gradually decreases from 90 degrees to 0 degrees, as described above, The single acting actuator is designed on the basis of producing a balance torque under two conditions.