Lichtvorhang mit Anzeigern für einzelne Lichtstrahlen und Betriebsverfahren

摘要

A light curtain system (10) includes a control circuit (13) having visible light indicators positioned adjacent channels (18) of individual light beams established across a guard zone. The light beams are transmitted along a plurality of parallel channels between a transmitter bar (11) and receiver bar (12). The control circuit operates to sense when one or more beams are blocked by the intrusion of an opaque object. The circuit responds by operating visible light LEDs (72) which are positioned adjacent the channels of the blocked beams. The visible light provides continuous feedback to the machine operator as to the condition of the guard zone. The visible light indicators are also used to facilitate alignment of the transmitter and receiver bars.