GB1007604A - Improvements in or relating to means for operating doors - Google Patents

Abstract

1,007,604. Door operating devices; door closers. LANDERT-MOTOREN A.G. April 2, 1962 [April 10, 1961], No. 12603/62. Heading E2M. An hydraulic door operating appliance comprises a door driving cylinder 14, a pump 2 driven by an electric motor, a pressure accumulator 5 adapted to supply pressure fluid to open the door, and a door closing spring (not shown) the motor and pump being in operation for the entire opening process, and during the time that the door subsequently remains open, and the accumulator being recharged by the pump during such subsequent time. When the motor and pump are started the pressure fluid in pipe 3 passes through non- return valve 4 to pressure accumulator 5 and also depresses a differential valve 6 which opens a ball valve 9 to admit fluid from both the pump and the accumulator to the pressure chamber 13 of the driving cylinder 14 via pipe 10, valve 11 and throttle 12. As the door approaches its fully open position the escape of fluid from the cylinder chamber 16 through apertures 17 is prevented by the piston 15 and the speed of the final closing movement can be controlled by a throttle 19. Once the door is fully open and the pressure accumulator has been recharged further fluid delivered from the pump drains away through a safety valve 21. When it is desired to close the door the motor and pump are stopped and the valve 6 rises under the action of spring 7, thereby opening an outlet 8 to permit the closing spring (not shown) to move the piston into the cylinder, the speed of closing being controlled by throttles 24, 25. The valve seats for the valve balls 4, 9 are made of material such as nylon to minimise pressure loss from the accumulator during the periods between operations. The appliance can also function as a door closer when the door has been opened manually, the cylinder 14 acting as a dashpot. Specifications 303,978; 328,359 and 1,007,605 are referred to.