These valves control large oil flows via small electrical signals. A small torque motor regulates the flow connected to this valve. Often implemented as multi-stage.
Comparing servo valve with a proportional valve
In general, the same functions can be performed with proportional valves as well as servo valves. The advantages of the servo valves are the higher accuracy and speed. Proportional valves, on the other hand, are simpler and more robust or service-friendly. since the oil has to be filtered less and the maintenance intervals are longer.
Servohydraulics is often applied to control circuits, that means using a measuring system and an analog controller.
|Proportional valve||Servo valve|
|• More robust against soiling|
• easier to maintain
|• High reactivity and controllability
• Smaller reaction time
• Smaller hysteresis
• Smaller power consumption