| 摘要 |
An apparatus for detecting labels on a carrier material has a transmitter that emits ultrasonic waves and a receiver that receives ultrasonic waves. The carrier material is located, with the labels, between the transmitter and the receiver. For detecting the labels, the received signal is compared to a threshold value at the output of the receiver. The threshold value is determined automatically, as a function of the received signal registered during a balancing procedure when the carrier material and/or labels are located between the transmitter and the receiver. In an alternative embodiment of the invention, the apparatus is used to distinguish between single and multiple sheets.
|
