GB859042A - Improvements relating to extensible arms or mountings - Google Patents

Abstract

859,042. Drawer runners. LAURENCE, SCOTT & ELECTROMOTORS Ltd. July 9, 1957 [April 9, 1956], No. 10819/56. Class 52(1) [Also in Groups XXIII and XXXIV] An extensible arm used, for example, slidably to support a drawer in a cabinet comprises three members 1, 2 and 3 which are so interconnected that, when member 2 is moved relatively to member 1, member 3 moves relatively to both members 1 and 2. The members 1, 2, made of metal, are of channel cross-section and are provided with freely-rotatable rollers 4 which are mounted on the channel flanges and roll in grooves 5 provided in the member 3 which is located between the members 1, 2 and may be of rectangular-section metal bar. In recesses near each end of the member 3 are rotatably mounted pulleys 6, 61 over which passes an endless belt 7, for example, of steel which is anchored between metal blocks 8, 9 secured to the members 1, 2 respectively so that, when the member 2 is pulled along with respect to the member 1, the member 3 is also moved. A handle 10 may be connected to the member 2, and the members may be locked in a number of positions by means of a spring-biased detent 17 which engages one of a number of holes 18, 18<SP>1</SP> in the member 3 and is released by pressing a button 15 connected to the detent by a metal strip 16. Electric, hydraulic or pneumatic power may be led by means of flexible wires or pipes through the member 1 to the member 2 for use with apparatus which may be carried in the drawer. For example, a bundle of flexible wires 11, led into the member 1 through an opening 12 therein, passes round the pulley 6 and out through a bushed. opening 13 in the member 2; if required a second bundle of wires may be led round the pulley 61 in a similar manner. The endless belt 7 and the pulleys 6, 6<SP>1</SP> may be replaced by an endless chain and sprocket wheels, or at least one toothed pinion may be provided on the member 3 to mesh with racks formed on the flange edges of the members 1 and 2, and in the latter case the member 2 may be extended in either direction relative to the member 1. Rotation of apparatus within the drawer may be effected by a shaft mounted upon a sprocket 21 which is connected to a further sprocket 23 by an endless chain 22 passing around further sprockets 20, 201 mounted coaxially with the pulleys 6, 61. The arm may be used for carrying power to a grinding wheel motor supported on the slide of a lathe.