Patent GB-1234861-A (GB)
Title: Improvements in or relating to conveyor constructions
IPC: B65G47/26
Filed: 1969-03-17
Abstract: 1,234,861. Roller conveyers. GENERAL LOGISTICS CORP. 17 March, 1969 [20 March, 1968], No. 13940/69. Heading B8A. [Also in Divisions F2 and H2] In a roller conveyer, coupling means associated with each roller comprises a pair of relatively rotatable parts having permanent magnetic attraction therebetween. In Fig. 2 a conveyer roller comprises a driving section 46 coupled to a driven section 44 by a magnetic torque limiting transmission 48 which includes annular permanent magnets fit, 66 each provided with single or multiple poles. When articles are stopped on the conveyer, the transmission slips in a pulsating fashion until the articles are permitted to move. A guard 50 prevents articles engaging the driving roller sections 46 which are driven by an endless belt 54 urged by snub rollers 56 into engagement with the sections 46. Roller axles 40 are non- rotatable. One of the annular magnets may be replaced by one or more magnetizable slugs or by deformed surfaces of a steel washer, Figs. 2A, 2B (not shown). In Fig. 3 (not shown) a tubular magnet (86) is secured to the driving roller (46<SP>1</SP>) and, by induction, drives the roller section (44<SP>1</SP>). By adjustment of the overlap between the magnet and the section (44<SP>1</SP>) the amount the torque transmitted can be varied. In Fig. 5 (not shown) annular magnet (106) on the roller section (44) coacts with sleeve (110) of magnetic material attached to the drive roller (46<SP>1</SP>). A slug (112) or ring magnet may be attached to the outside of the sleeve (110), Fig. 6 (not shown). By moving the slug along the sleeve or by varying the size of the slug the transmitted torque may be varied. In Fig. 7, a roller 114 forming part of a gravity conveyer has a permanent magnet 116 which coacts with an electrically conductive side rail 120. The drag resulting from eddy current induction is adjustable by varying the gap between the magnet 116 and the rail 120. An annular magnet (116<SP>1</SP>) may be secured to the rail (120), Fig. 7A (not shown), drag between the magnet and one or more slugs (23) on the roller (114<SP>1</SP>) being magnetic and frictional if the axial position of the roller is suitably adjusted longitudinally. When the magnet (116<SP>1</SP>) is on the roller, slugs (123<SP>1</SP>) may be formed on the rail (120<SP>11</SP>), Fig. 7B (not shown). In Fig. 8 (not shown) a stationary magnet (122) within the roller (114<SP>1</SP>) is circumferentially polarized for interaction with the electrically conducting shell (126) of the roller. For additional drag, further magnets (128) may be provided. In Fig. 9, roller axle 132 is rotatable and carries a discoidal magnet 142 which drives the roller shell 144 by induction. The axle 132 carries a sheave 134 for engagement by a belt 136. As a modification, one or more magnetizable slugs 142a may be secured on the roller to provide magnetic drive. In Fig. 10, transmissions 148 include central magnets 156 movable axially of the rollers. As shown, drive exists between these magnets and magnets 152 on the rollers 44<SP>1</SP>. When articles on the rollers 44<SP>1</SP> are held up, the resulting slippage between the central magnets 156 and the magnets 152 causes misorientation between unlike poles and the magnets 156 are repulsed to their decoupled positions, Fig. 10B (not shown). To restart the driven rollers 44<SP>1</SP> cam means 162, 164 is operated and the magnets 156 re-engage the magnets 152. In Fig. 12 a cog-belt 208 drives a toothed member 210 on the driving roller 46<SP>1</SP> which is axially movable for coupling and uncoupling of magnets 200, 202. In Fig. 13, conveyed articles are spaced when a brake block 220 is raised into contact with a number of rollers, as a result of depression of a sensing roller 211 by a leading article 214. By making the driving rollers of differing diameters, the corresponding driven rollers revolve at differing speeds and spacing or closing-up of the articles is obtained according to the direction of drive by the belt, Figs. 14, 15 (not shown). Drive for rollers (46<SP>1</SP>) may be by individual motors (240), Figs. 16, 17 (not shown), the coupling being a combination of eddy current and magnetic effect. Rollers having the magnetic couplings may be mounted on a tank wall, Figs. 18, 19 (not shown) the driving rollers, belt and snub rollers being outside the tank.