摘要 |
A photoelectric switch includes a base having a tubular wall surrounding an axis, and a cover coupled to the base and including a rib unit that cooperates with the tubular wall to confine a rolling chamber. The rib unit has at least one portion overlapping the tubular wall. A light passage extends through the rolling chamber and two diametrically opposite sides of the tubular wall. A photoelectric unit is enclosed by the base and the cover, and includes a light emitter and a light receiver disposed respectively on two opposite ends of the light passage, and a rolling member disposed in the rolling chamber and movable between a blocking position to block the light passage and a non-blocking position to unblock the light passage. |