For the detection of adhesive spots in the packaging has Pepperl + Fuchs Sensors in the portfolio that reliably ensure a continuous packaging process. The Ultrasonic sensors Monitor stacking height independent of color, shape and surface - and maintenance-free. Learning the sensors is super easy.
Many packaging contains protective or stabilizing plastic parts that conform to the contour of the product. These include trays in candy boxes or presentation holders for cosmetics. These moldings are usually made by deep drawing. The film-like starting material is guided by rollers in the machine. At the end of a used roll, the beginning of the new roll is fixed by means of adhesive tape. This circumvents a complex re-threading. However, the connecting adhesive strip must not get into the thermoforming unit. It is not necessarily suitable as a material for the molding and would hinder the process by unwanted adhesion in the thermoforming.
The connection between the film rolls must be reliably detected. This also applies to splices within a roll, because these can be composed of several lots. These transitions are cut out before deep drawing.
A second task in the packaging process is often to monitor the supply of finished moldings at the feeder for packaging assembly. In both cases it is important to avoid any interruption of the process.
Two tasks - one sensor
Ultrasonic sensors are ideal for both tasks. They recognize the material of the roll goods and the finished molded parts regardless of their optical properties. Even the inevitable electrostatic charge of the plastic films is irrelevant to them.
The ultrasonic splice sensor UGB 18GM50-255 reliably detects the sticky area with a response time of only 600 ╬╝s based on its sound damping behavior deviating from the roll material. The stack height of the stock of finished molded parts is, for example, with the ultrasonic sensor UB400-F77-E2-V31 measured with millimeter accuracy. Other designs are also suitable for this application. The user can choose between continuous monitoring and setting a limit that triggers the refill.
Reflecting surfaces - no problem
The foils can be of any color or printed in multiple colors. Often they are transparent or have reflective surfaces. The moldings have irregular contours, often with recesses or steep recesses.
All of these influencing factors are irrelevant for ultrasound devices. The same sensor can be used for a wide range of materials, even with highly diversified shapes. In the case of ultrasound splice detectors, the very short reaction time of 600 ╬╝s enables rapid removal of the splice with the least possible material waste. The sensors allow a dynamic teach-in while the machine is running. The teach-in of the sensor can be done directly from the PLC via a digital output.
The splice sensor UGB-18GM50 has an extremely short response delay, is compact and detects objects 20 up to 60 mm distant. The reflection button UB400-F77, on the other hand, captures 25 to 400 mm distant objects and has a teach-in input. Both sensors are very compact.