GB1239332A - - Google Patents

Abstract

1,239,332. Railway systems; conveyer systems. REGIE AUTONOME DES TRANSPORTS PARISIENS, and AUTOMATISME ET TECHNIQUE. 22 July, 1969 [23 July, 1968], No. 36741/69. Heading B7L. [Also in Division F2] A variable-speed friction drive for use in a number of applications such as a slow cutting and rapid return machine tool (not shown), or an automatic programmed painting line permitting articles to be processed past a series of working stations at different speeds and thus different treatment times, or programmed to equal the speed of and maintain balance support via a lattice (66), Fig. 9 (not shown) of fragile articles (67) born by a variable-speed conveyer or, as shown, a hand-rail for a variable-speed travelator (i.e. pedestrian conveyer belt), comprises a number of spaced pulleys 11 rotatably supported on spindles 9 of yokes 7 which carry the travelator hand rail blocks 5 and are supported by rollers 8 in tracks 2 of a carriage structure 10, the pulleys 11 being driven via a chain 31 and pulley sprockets 37, or individual electric motors (51) supplied via a conductor rail (55) (Fig. 5, not shown), along a cam track 23 the effective distance (d 1 , d 2 ) of which relative to the centre of the pulley 11 varies according to their position along the track to vary the effective rolling radius of the pulleys 11 on the track and hence their speed therealong. As shown, the pulleys 11 have one, or both (not shown), conical flanges 12, 13 axially movable and spring loaded together against the cam track 23, the flanges 12, 13 merely relatively separating or closing according to the depth of penetration therebetween of the cam track 23 the relative disposition of which may be adjusted by threaded studs 24 located on carriage brackets 23. Alternatively, solid fixed flanged pulleys (61) (Figs. 7 and 8, not shown), may engage a variable width, i.e. variable crosssection cam track (62), the complete pulley (Fig. 8) being spring loaded into engagement with the track formed as a straight member (Fig. 8), or, with the cam track (62) formed, as before, to vary depth of penetration in the pulley (Fig. 7). In Fig. 6 (not shown) the pulley flanges (12a, 13a) are formed with curvilinear faces to vary the speed characteristics of the pulley on a rounded edge cam tract (23a).