Detecting Plastic Wrap on a Can
In the application shown, the plastic wrap surrounding the cap and the top of the can serves several purposes: it acts as a tamper-proof seal on the can, it prevents the cap from disconnecting during transit, and it holds the applicator tool to the can. Additionally, the plastic serves as error-proofing to protect customers from spilling the contents before they are ready to use it. For these reasons it is important that cans without the plastic wrap are rejected.
Because the plastic used exhibits luminescent properties, a QL56 Series Luminescence Sensor can be used to detect the presence of the wrap, and any cans without the plastic will be rejected.
Luminescence sensors emit ultraviolet (UV) light from high-power LEDs and detect visible light created by luminescent targets. This technology allows for the detection of luminescent marks (even invisible ones) on any surface, independently from its material, color, or distance inside the operating range, as long as the target radiates visible light when illuminated with UV light.
The QL56 sensor uses six UV LEDs which create a uniform and intense line of UV light. The structured light allows for reliable detection of luminescent materials on irregular surfaces, such as the plastic on the cap in this application. Additionally, the sensor is easy to set up and the durable aluminum housing ensures robust performance.