Device for detecting a sufficient glue coating of a paper strip

A cigarette forming machine, comprising:

• glue applicator means for applying a glue coating on a first surface a filter paper strip to be adhesively bonded about filters and cigarettes;
• a sliding plate having a plate surface engaging a second surface of the filter paper strip, opposite to the first surface, and over which the filter paper strip runs in a first direction, said plate surface having groove-shaped channels oriented at angles of between 10 degrees and 80 degrees relative to said first direction;
• a plurality of capacitive sensors, for detecting presence of moisture in the glue coating in a discontinuous, recurring pattern on the first surface of the filter paper strip, directed toward the second surface of the filter paper strip, mounted in recesses in said plate surface of said sliding plate and arranged in a row extending transversely to said first direction;
• a control means coupled to said sensors for evaluating signals emitted from said sensors and for emitting a fault signal for controlling the cigarette machine when the moisture sensed in the glue coating is insufficient;
• and
• conveying means for moving the filter paper strip to and from said glue applicator and said sliding plate.