The "double sheet control" application originally comes from the printing industry. Here, the appearance of a double sheet or a splice in the paper must be quickly and reliably detected. As the sheet runs between the opposing emitter and receiver, the sensors continuously monitor the status of the entire length. Due to their special design, double sheet sensors are ideal for the following applications:

• Identifying multiple feeds of
  • Paper
  • Plastics (i.e., vinyl)
  • Metals
• Label detection
• Splice detection

Double sheet sensors are ideal for distinguishing between the following:

• Air/one sheet/two+ sheets
• Air/backing material/backing material with label applied
Air/single layer of material/two layers of material stuck together
• Air/single plate/two or more plates (i.e., sheet metal)

Features:

• Thin papers with a density of 10 g/m up to cardboard with a density of 2000 g/m can be monitored
• Detection of thin plastic or metal films
• Customized Teach-in of various materials
• Suitable for use on shiny and transparent materials
• Automatic adjustment of the switching thresholds to changing ambient conditions
• Very high processing speed
• Insensitive to dust and dirt

Application examples:

• Printing press applications, where the ultrasonic double sheet control protects the complex mechanics from being destroyed by preventing two sheets from being pulled in, or identifies a sheet lodged in the machine
• The control of adhesive films in labeling machines, including label counting
• Letter-opening devices, where the opened letters are checked to ensure they have been fully emptied
• Receipt-counting machines
• Packaging machines, where splices identify the start of a new sheet and end of the old one
• The detection of gaps, single sheets, and double sheets in paper processing machinery

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