Safety switching for passenger conveyor

Claim 2

A safety switching system for passenger conveyors and the like, comprising means responsive to the condition of a conveyor for stopping the same upon occurrence of an unsafe condition, said means responsive comprising switch means for normally establishing a first circuit for conveyor energization to effect movement thereof in a first direction and for establishing upon occurrence of such unsafe condition a second circuit for conveyor energization to effect movement thereof in a reverse direction, and selectively operable means coupled to said means responsive for restarting said conveyor in reverse direction after said means responsive has sensed occurrence of such unsafe condition.

Claim 3

A safety switching system for passenger conveyors and the like as set forth in claim 1, wherein said switch means comprises plural switch means positioned proximate respective ends of said conveyor.

Claim 4

A safety switching system for passenger conveyors and the like as set forth in claim 1, wherein said conveyor comprises a moving part and a normally relatively stationary part, and said switch means being positioned proximate said stationary part and being responsive to a foreign object entering between said stationary part and said moving part.

Claim 5

A safety switching system for passenger conveyors and the like as set forth in claim 3, wherein said moving part comprises a moving conveyor portion, and said stationary part comprises respective landing plate assemblies positioned at opposite ends of said conveyor portion, said switch means comprising first and second switch means positioned on opposite sides of a first one of said landing plate assemblies and third and fourth switch means positioned on opposite sides of the other one of said landing plate assemblies, said switch means being responsive to a lifting of said respective landing plate assemblies for stopping conveyor movement upon sensing such lifting.

Claim 6

A safety switching system for passenger conveyors and the like as set forth in claim 4, wherein said means coupled comprises emergency switch means for controlling conveyor energization and movement thereof, said emergency switch means being connected for interrupting conveyor movement upon actuation during normal operation of said conveyor.

Claim 7

A safety switching system for passenger conveyors and the like as set forth in claim 1, wherein said means coupled comprises emergency switch means for controlling conveyor energization, said emergency switch means being connected for interrupting conveyor movement upon actuation during normal operation of said conveyor.

Claim 8

A safety switching system for passenger conveyors and the like as set forth in claim 6, further comprising key-operated switch means coupled to both said means responsive and said means coupled for effecting starting of said conveyor in said first direction.

Claim 9

A safety switching system for passenger conveyors and the like as set forth in claim 7, further comprising annunciator means coupled to said emergency switch means for indicating operative condition of said conveyor.

Claim 10

A safety switching system for passenger convEyors and the like as set forth in claim 1, wherein said means responsive stops reverse conveyor movement upon sensing termination of such unsafe condition.

Claim 11

A safety switching system for passenger conveyors and the like comprising means responsive to the condition of a conveyor for stopping the same upon occurrence of an unsafe condition, said means responsive comprising switch means for normally establishing a first circuit for conveyor energization to effect movement thereof in a first direction and for establishing upon occurrence of such unsafe condition a second circuit for conveyor energization to effect movement thereof in a reverse direction, means coupled to said means responsive for restarting said conveyor in reverse direction after said means responsive has sensed occurrence of such unsafe condition, said means coupled comprising emergency switch means for controlling conveyor energization, said emergency switch means being connected for interrupting conveyor movement upon actuation during normal operation of said conveyor, and further comprising first and second relay means for effecting energization of said conveyor respectively in said first and reverse directions, said relay means being coupled to said emergency switch means, whereby said emergency switch means normally provides one circuit for energizing said first relay to effect conveyor movement in said first direction and interrupting said one circuit upon actuation thereof to de-energize said first relay means stopping such normal conveyor movement, said emergency switch means providing upon actuation another circuit for energizing said second relay means to effect conveyor reverse movement when said means responsive has sensed the occurrence of such unsafe condition.

Claim 12

A safety switching system for passenger conveyors and the like comprising means responsive to the condition of a conveyor for stopping the same upon occurrence of an unsafe condition, said means responsive comprising switch means for normally establishing a first circuit for conveyor energization to effect movement thereof in a first direction and for establishing upon occurrence of such unsafe condition a second circuit for conveyor energization to effect movement thereof in a reverse direction, means coupled to said means responsive for restarting said conveyor in reverse direction after said means responsive has sensed occurrence of such unsafe condition, said means coupled comprising emergency switch means for controlling conveyor energization, said emergency switch means being connected for interrupting conveyor movement upon actuation during normal operation of said conveyor, and further comprising first and second relay means for effecting energization of said conveyor respectively in said first and reverse directions, said relay means being coupled to said emergency switch means, whereby said emergency switch means normally provides one circuit for energizing said first relay to effect conveyor movement in said first direction and interrupting said one circuit upon actuation thereof to de-energize said first relay means stopping such normal conveyor movement, said emergency switch means providing upon actuation another circuit for energizing said second relay means to effect conveyor reverse movement when said means responsive has sensed the occurrence of such unsafe condition.

Claim 13

A safety switching system for passenger conveyors and the like as set forth in claim 10, further comprising first and second pairs of normally closed contacts, each such pair being coupled in series with a respective one of said first and second relay means and controlled by the other one of such relay means, whereby upon energization of one of said relay means the other of said relay means is disabled from energization.

Claim 14

A safety switching system for passenger conveyors and the like as set forth in claim 10, further comprising first and second normally open contact means respectively coupled in said one and another circuits in series with said first and second relay means and controlled thereby, first and second normally open start switch means respectively coupled across said first and second normally open contacts for providing upon actuation a short circuit across such contacts to effect energization of a respective one of said first and second relay means, whereby actuation of one of said start switch means effects energization of the respective ones of said first and second relay means which in turn closes its associated contacts to continue energization thereof upon release of said start switch means.

Claim 15

A safety switching system for passenger conveyors and the like as set forth in claim 12, wherein said start switch means comprises key-operated switch means.

Claim 16

A safety switching system for passenger conveyors and the like as set forth in claim 13. wherein said conveyor comprises a moving conveyor portion adaptable for movement in either of two directions and respective first and second landing plate assemblies positioned at the respective ends of the former, said switch means being positioned with respect to said first and second landing plate assemblies to detect the lifting thereof, and said emergency switch means comprises a plurality of the same, one located proximate each end of said moving conveyor portion.