Pneumatic diaphragm-type actuator for control valve

The utility model relates to the technical field of control valves, and provides a pneumatic diaphragm-type actuator for a control valve. The pneumatic diaphragm-type actuator for the control valve comprises a diaphragm head. The diaphragm head comprises an upper diaphragm cover and a lower diaphragm cover which are connected with each other. The upper diaphragm cover and the lower diaphragm cover are of the same structure. The pneumatic diaphragm-type actuator for the control valve further comprises a push rod assembly. The push rod assembly comprises a push rod body, a diaphragm and trays. The top end and the bottom end of the push rod body penetrate through the diaphragm head. The top end of the push rod body and the bottom end of the push rod body are of the same structure. Spring components are arranged between the trays and the lower diaphragm cover. When the pneumatic diaphragm-type actuator for the control valve is applied to a positive action type, the bottom end of the push rod body is connected with a valve rod through a connecting component. When the pneumatic diaphragm-type actuator for the control valve is applied to a negative action type, the top end of the push rod body is connected with the valve rod through the connecting component. On the condition that no other components are added or omitted or replaced, the mutual conversion of the positive action type and the negative action type is achieved on the same actuator. By adopting an adjusting screw nut and the connecting component, the range of the spring components can be changed without replacing the spring components.