Abstract: Sensor components having sides facing the sheet material have one or a plurality of front elements which are detachable and replaceable with low effort. So in the case of wear of the sensor fronts, entire sensor components no longer have to be replaced but only individual front elements of the sensor component are replaced. The front elements do not contact the inner area of the housing and the sensitive measuring elements arranged therein. When the front elements are detached from the housing for maintenance, the measuring elements remain dustproof encapsulated in the housing of the sensor component. The front elements preferably have a comb structure which improves the transport of the bank notes at the transition between the sensor components.

Abstract: In bank note processing machines bank notes are conveyed by a transport system and thereby pass through a sensor path. With some sensors the bank notes guided past touch the front side of the sensor housing. Thus, the front sides wear out which may impair the transport of the bank notes. In the case of wear of the sensor fronts, no longer complete sensor components but only individual front elements of the sensor component are replaced. To the side of the sensor housing facing the bank notes there are fixed one or a plurality of front elements which are detachable and thus replaceable with low effort. The front elements do not contact the inner area of the housing and the sensitive measuring elements arranged therein. When the front elements are detached from the housing for maintenance, the measuring elements remain dustproof encapsulated in the housing of the sensor component.