Proportsiooniventiile

Proportsiooniventiile are valve systems used in hydraulic and pneumatic circuits to provide continuous, proportional control of fluid flow or pressure. They translate an electrical control signal into a variable valve opening, allowing smooth modulation of actuator speed or force rather than simple on/off operation.

Operation typically involves a control signal, such as 4-20 mA or 0-10 V, which drives an electromagnet that positions a valve element. The degree of opening is proportional to the input signal, enabling analog control of flow. In many configurations, a feedback device such as a position sensor or pressure transducer is used to form a closed-loop servo arrangement, improving accuracy and repeatability.

Types and configurations vary. Some valves are direct-acting, where the solenoid directly shifts the valve element, while others are pilot-operated, using a small pilot valve to control a larger main valve. Proportsiooniventiile can be implemented as open-loop proportional valves or closed-loop servo valves; two-stage designs with a pilot stage are common in higher-performance applications.

Applications encompass industrial automation, machine tools, presses, robotics, plastic processing, and other systems requiring precise speed or force control of hydraulic or pneumatic actuators. They offer the advantage of smooth, continuous control and fast response, but may exhibit nonlinearity, hysteresis, temperature sensitivity, and leakage. Performance depends on fluid quality, system pressures, and proper matching to the control signal range and power supply.

Maintenance considerations include contamination control, regular filter changes, and periodic calibration of the control signal and valve response to maintain accuracy.