In the production process of automobiles, their surfaces need to sprayed with paints. Then measuring light curtains are in need. Measuring light curtains measure objects?? surface dimension and shape by scanning. It form objects??surface shape and dimension according to the number of light beams which are interrupted. Then it will transmit the acquired signal to the spraying control system. The spraying control system is set by software and at mean time transmits a signal to the spraying robot arm to spray paints on the workpiece??s surface. When one workpiece finished, the system will give the next signal to spray the next workpiece. The details can be seen in the diagram of measuring light curtains.
Photoelectric sensor is a kind of electronic device which senses the light strength??s variation. It consists of optic system, amplifier and on-off output device. All the photoelectric sensors adopts modulated light to exclude the possible interference of lights at surroundings. When at work, the photoelectric emits light when the objects to be detected pass.According to the different detection method, the objects either absorb the lights or reflect the lights to the light absorber of the photoelectric sensor.The strength of light received by the absorber will vary and its variation value will trigger the output of on-off signal and realize the function of detection.
Light curtain measuring system needs to be equipped with a controller to work normally. The controller is set by software to program and it can provide various scanning mode and detection and analysis modes. And it can communicate with PLC and computer through serial interface,and transmits control or scanning result. Besides, it can be connected with trigger signal and control scanning process.