Speed Control Valve allows the ECU to change engine idle speed to meet different engine conditions. Flow-rate accuracy is high. The control valve type is a step motor. Using the screw mechanism the valve position converts the rotor angle into axial direction. Accurate engine idle speed control results in high drivability, improved emissions and fuel economy.
Speed Control devices can take on many forms. The Valving can be utilized to control flow to a hydralic motor to obtain speed control of the shaft. An open loop could have a speed control function. The feed back path becomes necessary to maintain the speed output with changes in load and environmental influences.