| 摘要 |
A proximity switch assembly (10) for signaling the location of a movable member (36) at either of opposite end limits of movement relative to a stationary frame (44,46) includes a compact elongate housing (58) adapted to be mounted on the frame to extend along the path of movement of a power driven member (32), such as the piston rod of a hydraulic cylinder, which shifts the movable member between its end limits. The proximity switch is fixedly mounted in the housing and carries a switch actuating member (74) mounted for sliding movement over a relatively short distance sufficient to move two actuating targets (104,106) into an out of actuating proximity of respective air core proximity sensing coils (132,134) within the housing. Lost motion abutment structure (76,78) on the switch actuation member and power driven member (54) move into engagement with each other as a power driven member approaches each end of its stroke. Separate sensing circuits (156,158) provide discrete outputs associated with each end limit of travel of the movable member.
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