GB795592A - Power actuated mechanism for elevator closures - Google Patents

Abstract

795,592. Door-operating appliances. OTIS ELEVATOR CO. May 28, 1956 [June 7, 1955], No. 16395/56. Class 65(1) A door - operating, device comprises a housing 4, a reversible motor 3 mounted externally on the housing, a door-operating member 17 outside the housing, mechanism within the housing for transmitting power from the motor to member 17, and hydraulic means within the housing connected in continuous engagement with the powertransmitting mechanism for checking the final part of the opening and closing movements of the door. The motor shaft 5 is connected with a shaft 14, carrrying mem- - ber 17, by a train of reduction gearing 6, 7, 10, 13. A rack 18, driven by gear 13, carries at each end a check piston 20 which is disposed in a cylinder 21 and is provided with a non-return valve 26. Each cylinder communicates via a series of ports 29 and a passage 27 with an oil reservoir 28. A rotatable valve 30 disposed in passage 27 has a hollow end formed with a series of ports 31 which are arranged helically so as to be selectably alignable with the ports 29. Each cylinder end communicates with the oil reservoir via a passage having an internally screw-threaded portion 43. A smooth cylindrical valve stem 39, disposed in portion 43, restricts the flow of oil therethrough to a helical path, the length ofwhich may be varied by screwing stem 39 in or out. The extent of the unchecked movement and the intensity of checking is varied by adjustment of the valves 30 and 39, respectively. In a modification, valve stem 39 is screwthreaded and the portion 43 is smooth.