Multi-beam photoelectric safeguard system

摘要

A multi-beam photoelectric safeguard system (100) includes a sub light detecting device (14) and a sub light emitting device (13) that are placed in a parallel, spaced-apart relationship inside a plane extending between a main light emitting device (11) and a main light detecting device (12). When the system is used to make a light curtain for a machine having a projecting portion that significantly projects outwardly from the main part of the machine, the sub light detecting device and the sub light emitting device are disposed adjacent to the opposite sides of the projecting portion to receive light beams from the main light emitting device and to emit light beams toward the main light detecting device. Thus the system makes a light curtain extending all around the projecting portion without leaving any zones on the opposite sides of the projecting portion within the plane of the light curtain that cannot be detected.