Detecting Glass Panels
Challenge
Large colored glass panels are conveyed through the production process on rollers. For positioning purposes, it’s necessary to detect the edges of the panels as they pass. Applications where the sensors must be mounted looking up can prove challenging because factory lighting can cause unreliable sensing. An added difficulty in this application is the lack of a fixed background.
Solution
WORLD-BEAM QS18 Adjustable-Field Sensors with Background Suppression feature enhanced immunity to fluorescent lights, enabling them to reliably detect the edges of the glass panels despite looking up at the factory lights.
The difficulty of varying background conditions is solved by using background suppression. The cutoff distance is set by the user with a simple multi-turn screw adjustment. The sensor will ignore objects beyond the set cutoff distance.
In applications using QS18 Adjustable-Field Sensors with Background Suppression, the orientation of the object to the sensor is key. The object must travel perpendicular to the sensor face for reliable detection. Another thing to remember when using background suppression is that a minimum separation distance between the object and the background is required. In this application, there is sufficient distance between the glass panels and the factory ceiling.