GB648646A - Improvements in or relating to sliding doors and the like - Google Patents

Abstract

648,646. Door operating appliances. KING, Ltd., G. W. and BURROWS, A. T. C. July 22: 1948, No. 19650. [Class 65(i)] [Also in Group X] A vertically slidable door 10 is connected by a cable 16, passing around rollers 17, 18, to a counterweight 19 approximately equal to the weight of the door, and means are provided both for imparting an upward or downward movement to the counterweight as well as for supporting' the latter independently of the cable at a point in its upward movement corresponding to the closed position of the door. The door travels on rollers 13, 14 in guides 11, the lower ends of which are so curved as to displace the door, in its closed position, against a sealing gasket attached to the frame. The counterweight travels on rollers 20 in guides 21 and is adapted to be supported by the lower pair of said rollers upon a shelf at the top of its travel, the upper ends of the guides 21 being curved to provide the necessary lateral displacement for this purpose. The counterweight is driven by a motor 22 through a cable 25 which passes around pulleys 24, 26, 27. The ends of said cable are connected to the lower arms 32 of a bell-crank lever system, the upper arms 29 of which are pivoted to the counterweight, and the pivot 31 of which is provided with rollers which travel in the guides 21. The initial movement of the cable 25 to move the counterweight downwardly thus serves to dislodge the latter from its supporting shelf. It is stated that the door will rebound from the sealing gasket to cause slackening of the supporting cable, thus enabling the door to press against the gasket under the action of its own weight.