GB1274389A - Improvements relating to the control of doors - Google Patents

Abstract

1,274,389. Door control system. STONE MANGANESE MARINE Ltd. 19 April, 1971 [6 April, 1970], No. 16230/70. Heading E2M. A power operated fire door system has doors 8 held open normally by catches 9, the doors being closed, simultaneously, or in groups under power from a central station and each door 8 having a local means by the manual operation of which the door can be opened individually despite the central station being in the door closing condition, the door being then reclosed automatically. The doors can also be closed individually by local means when the central station is in the door-open condition. As shown the system is of electromagnetic and pneumatic construction, electrical control being shown as dotted lines, pneumatic as full lines, an air bottle 2 charged by a compressor unit 1 under the control of a pressure responsive switch 3 providing the pneumatic power. The normal, door-open, condition is with the switches 4 (at the central station) and 11 (at the individual doors, only one being shown) closed, so that the solenoids 10 and 12, to hold the door open and cut off the compressed air flow, are normally energised, the opening either of switch 4 (which closes all the doors) or of switch 11 (for an individual door) causing the release of catch 9 and the supply of air to a cylinder 16 to close the door associated with it. A valve 15 controlled by a lever or handle on the door connects the cylinder 16 associated with the door to exhaust at 17 so allowing an individual door 8 to be opened, a non return valve 19 facilitating the opening, the release of the handle causing the air to automatically reclose the door. An adjustable bleed valve 20 controls the rate of closing and double indicator lights 5 show whether the doors are open or closed, being connected to door operated switches.