(1) Actuators are classified into pneumatic, electric and hydraulic actuators according to the driving energy used.
(2) In the form of output displacement, the actuator has two types: angle type and straight type.
(3) According to the action rules, the actuator can be divided into three types: switch type, integral type and proportional type.
(4) According to the input control signal, the actuator is divided into several types: air pressure signal, DC current signal, electric contact on/off signal, pulse signal and so on.
