Patent GB-1533965-A (GB)
Title: Device for magnetically arranging ferromagnetic components at preset distances from one another
IPC: B65G47/26
Filed: 1977-04-01
Abstract: 1533965 Conveying by magnetic means INST FIZIKI AKAD NAUK LATVII SSR and RIZH POLITEKH INST 1 April 1977 13911/77 Heading B8A [Also in Division H1] An electromagnetic device arranging ferromagnetic components at a predetermined distance one from another comprises (Figs. 1, 3) an electromagnet 1 having polepieces 3 defining an outwardly tapered airgap in which is established a non-uniform magnetic field whose gradient is direct along the axis of symmetry of the gap. The latter embraces a non-magnetic component magazine 4 whose inlet end is opposed to a feed trough 5 adjacent the lower ends of the polepieces and whose outlet end is adjacent their upper ends. Opposed ferromagnetic racks 6 having spaced gaps therein separated by teeth are spaced apart by non-magnetic distance pieces 7 which are movable in a plane normal to the axis of the polar gap. On D.C. energization the graduated field (Fig. 2, not shown) lifts components from the trough into the magazine where they are spaced apart by mutual repulsion. The racks move synchronically step by step so that the components are successively captured and carried laterally by pairs of teeth of the racks and move successively up the magazine into the transfer position.  In a modification (Figs. 4, 5, not shown) the magnetic field is cyclically varied from a higher to a lower level by an automatic switch comprising, e.g. a multivibrator and thyristor or by an automatically operated shunt cyclically closing the pole gap of the electromagnet while the components in the vertical magazine are magnetically impelled upwards and also subjected to an opposed gravitational, centrifugal or aerodynamic force. Jamming in the magazine due to irregular feed rates is thus discouraged. In a modification (Fig. 6, not shown) the profiled poles are affixed normally to the plane of the electromagnetic circuit, and the racks are cylindrical and mounted on the polepieces to rotate about a common axis, so that the components are carried circumferentially at preset intervals. In a modification (Fig. 7, not shown) the profiled polepieces lie in the plane of the magnet ferromagnetic rods are fed end to end along a feed trough and successively stacked laterally in a vertical magazine. Ferromagnetic parallel bars extend horizontally from the top of the polepieces adjacent the head of the magazine; one of which bars locates internally a slidable toothed ferromagnetic rack within a non-magnetic distance piece; whereby the rods are successively picked up by the magnetic fields of adjacent teeth with one end sliding over the distance piece and the other clear of the opposite ferromagnetic bar. In a modification (Fig. 8) for assembling bolts and washers together the electromagnet 24 has profiled horizontal polepieces 26 embracing at right angles ferromagnetic bars 30 one of which encloses a slidable ferromagnetic toothed rack 31 for bolts 35 fed to magazine 33 by vibrating trough 34. A further ferromagnetic rack similar to that of Fig. 4 (not shown) and moving parallel to rack 31 are supplied with washers 37 retained between the teeth to move between ferromagnetic bar 30 and the ends of the dependent bolts. The racked batches are aligned, and are interposed or moved together to an assembly point.