M.D. Micro Detectors launches the new fork sensor FC4 series used to detect belt oscillation on polishing machines. Polishing machines are typically equipped with a belt programmed to oscillate continuously, in order to ensure a uniform processing of the panel and avoid defects. Since the raw material panel could be larger or smaller than the belt itself this must be oscillating to ensure a uniform polishing.The sensor is a good solution for this kind of applications, thanks to its four optical beams: the two internal check the oscillation width of the belt, the two external activate alarm output in case of incorrect positioning.T he alarm function allows you to avoid micro-mechanical switches (which are normally used in this kind of application) thus simplifying the wiring of the machine when you have to stop the belt in case of malfunction. Moreover, the absence of micro switches makes easier the introduction of the belt in the machine, even by unskilled personnel. A further advantage of the sensor comes from the use of two beams, which define correct belt oscillation, allowing the correct belt detection even in case of fraying, unlike the mono sensors that use one beam only, and avoiding typical regulation piston wear thus having a lower energy consumption.