Types of proportional valves
Classification by proportional valve control mode refers to the classification according to the electrical-mechanical conversion mode in the pilot control valve of the proportional valve. The electrical control part has various forms such as proportional electromagnet, torque motor, and DC servo motor.
(1) Electromagnetic type
The electromagnetic type refers to a proportional valve that uses a proportional electromagnet as an electrical-mechanical conversion element. The proportional electromagnet converts the input current signal into a force and displacement mechanical signal output. Then control parameters such as pressure, flow and direction.
(2) Electric type
The electric type refers to a proportional valve that uses a DC servo motor as an electrical-mechanical conversion element. The DC servo motor converts the input electrical signal into a rotational speed, and then passes through a reduction device and a conversion mechanism such as a screw nut, a rack and pinion, or a gear cam. , output force and displacement, and further control hydraulic parameters.
(3) Electro-hydraulic type
The electro-hydraulic type refers to a proportional valve that uses a torque motor and a nozzle baffle as the pilot control stage. Input different electrical signals to the torque motor, and output displacement or angular displacement through the baffle connected to it (sometimes the armature of the torque motor is the baffle), change the distance between the baffle and the nozzle, and make the nozzle spray The oil flow resistance changes, thereby controlling the output parameters.
The proportional control valve is a control valve that continuously and proportionally controls the flow, pressure and direction of the hydraulic system according to the input electrical signal, and its output flow and pressure can not be affected by load changes.
