limitatore

Limitatore is a device or mechanism designed to impose an upper bound on a variable, such as electrical signal level, mechanical position, speed, torque, or pressure. The term comes from limitare, meaning to limit. In engineering practice, limiters are used to protect equipment, ensure safety, and control performance across diverse fields.

Electrical and electronic limiters clamp or clip signals that exceed a preset threshold, preventing damage from overloads and controlling peak levels. They are common in audio and communications systems, where they reduce loud peaks to avoid distortion. Implementations include diode clamps, zener or avalanche devices, transistor-based limiters, and dedicated limiter circuits or integrated chips. They are distinct from compressors in that limiters aim for a hard or near-hard cap on amplitude.

Mechanical limiters restrict motion or travel of moving parts. Examples include physical stops, cam followers, and limit switches that stop or sensor-protected travel in machines, robots, and CNC equipment. Torque limiters or overload clutches disengage drive components when torque exceeds a preset value, protecting gearboxes and motors.

Speed limiters constrain rotational or linear speed, widely used in automobiles, industrial machinery, and safety-critical systems to comply with regulations or to prevent hazardous operating conditions. Pressure limiters, such as relief valves, maintain system safety by venting or relieving excess pressure.

Applications span consumer electronics, automotive safety, industrial automation, and process control. Key considerations in limiter design include response time, accuracy of the threshold, hysteresis, environmental robustness, and ease of calibration and maintenance.