초록 ▼

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

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.

대표청구항 ▼

A proximity switch for use with a power actuated device including a member mounted for movement between first and second limits of travel, said switch comprising: means operative to change conductive state in response to a control signal; first and second inductive circuit elements; means operative

A proximity switch for use with a power actuated device including a member mounted for movement between first and second limits of travel, said switch comprising: means operative to change conductive state in response to a control signal; first and second inductive circuit elements; means operative to electrically energize said inductive elements to establish substantially isolated flux fields thereabout, each said field disposed within the atmosphere surrounding its respective element and having a characteristic amplitude; first target means displaceable between a position remote from said first inductive element and a sensed position adjacent said first element to effect a change in said first element characteristic amplitude; second target means displaceable between a position remote from said second inductive element and a sensed position adjacent said second element to effect a change in said second element characteristic amplitude; circuit means operative to generate said control signal as a function of said change in at least one of said characteristic amplitudes; and means operatively engaging said member and said first and second target means to effect simultaneous reciprocal displacement of said first and second target means between said respective remote and sensed positions when said member alternately substantially arrives at one of its end limits of travel.