Proportional valves are essentially electronic flow controllers. Users can vary the input current to the solenoid, and the output flow of the valve will vary accordingly. The greater the input current, the greater the flow through the valve.
Typical applications are dynamically dispensing controlled amounts of air or gas, controlling downstream pressures, or accelerating/decelerating air cylinders.
Humphrey proportional valves are two-port, normally closed, direct acting, spring return type flow controllers.
What are Miniature Proportional Valves? Download our FAQ that appeared in Machine Design, July 2014.
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