GB1485981A - Automatic door operating system - Google Patents

Abstract

1485981 Operating a plurality of doors COAL INDUSTRY (PATENTS) Ltd 3 Jan 1975 [15 Feb 1974] 6990/74 Heading E2M A plurality of doors designed to be bperated in succession (e.g. air-tight doors in mines) is provided with separate operating means and open and close switches for each door and interlock means involving polarized relays to isolate the operating mechanisms of the other doors when one door is being opened; indicating lights (or other visual and aural means) signal the state of the doors and further switches prevent closing of a door when an object is adjacent. Fig 1 shows one of the doors and each door comprises a fluid pressure operator 6 acting on two door panels 1; each side of the door being provided with a control 15 having an opening switch 16 a closing switch 17 and a red and a green indicating light. Each door panel 1 also has a door 12 which is opened by an actuating cylinder (not shown) to equalise pressure on both sides of the main door prior to the main door opening. Tread plates 8, 9 act to stop and reverse any door closing action if contacted. When a switch 16 of a particular .door is actuated a relay is operated to isolate the operating mechanisms of the other doors, to turn the indicating lights of all the doors from green to red, and to open the doors 12 in the door. When doors 12 are open power is supplied to the main door operating mechanism and when the main door is fully open the indicating lights on that door turn from red to green (remaining on red for the other doors). To close the door a switch 17 is actuated and the operating means acts in the opposite direction, the door lights turning from green to red. When door panels 1 are closed, the lights of this door return to green and doors 12 are closed. When this has taken place the lights on the other doors return to green.