SISTEMA DE REALIMENTACAO PARA CONTROLE DA VELOCIDADE DE UM MOTOR E SISTEMA PARA PULVERIZACAO E DISTRIBUICAO DE MATERIAL DE REVESTIMENTO

摘要

The speed of a fluid motor is controlled by an optical feedback system to control a spray gun for the final coating on a motor vehicle. The speed takes account of the coating characteristics and the variable loading effects. The fluid motor comprises an output shaft on which an atomiser is mounted. A supply tube provides the coating material from one of several sources via contr controls and is sprayed onto an object which is at an electrostatic potential. An optical head assembly contains an optical fibre to conduct light from a source. An optical receiver mounted within the motor casing provides a signal reflected from a pattern on a disc on the motor shaft. Electronic circuits respond to the received light to compare rotational speed with a time base to provide a speed control signal for the motor.