GB1220145A - Improvements in or relating to magnetic couplings - Google Patents

Abstract

1,220,145. Magnetic couplings. COMPAGNIE DE CONSTRUCTION MECANIQUE PROCEDES SULZER. 2 July, 1968 [3 July, 19671, No. 31442/68. Heading H2A. An eddy current magnetic coupling comprises a driving rotor and a driven rotor both made of good magnetic permeability material and both adapted to rotate in a magnetic field produced by a fixed winding or by at least one rotating permanent magnet, one rotor being provided with projecting teeth and the other, opposite the teeth, with a continuous layer of high electrical conductance metal. An asynchronous coupling, Fig. 1, comprises a stationary winding 2, a driving rotor 3 having two toothed ferromagnetic rings 8, 9 separated by a ring 11 of non-magnetic material, and a driven rotor 4 comprising a ferromagnetic annulus 15 carrying opposite the teeth 12, 13, layers 17, 18 of conductive metal. The driving rotor may be located radially within the driven one, Fig. 4 (not shown), and the winding may be located radially within the rotors, Fig. 6 (not shown). Alternatively, Fig. 7 (not shown), the two rotors may project axially into an open ended channel in a C-shaped stationary member (45), this channel also containing the winding (47). In a discoidal motor, Figs. 8, 9 (not shown), radially disposed teeth on discs (55) carried by one rotor are disposed axially adjacent conductive metal layers (68) on discs carried by the other rotor. In a further asynchronous coupling, Fig. 17, a plurality of circumferentially spaced axially magnetized magnets 86 are mounted between two toothed ferromagnetic rings 84, 85 on the driving rotor. The magnets may be replaced by a single axially magnetized annular magnet. In a modification, Fig. 19 (not shown), torque control is effected by an axially movable auxiliary magnetic member (90) located on a stationary member (94) radially within the driving rotor. In a further modification, Figs. 20, 21 (not shown), a heteropolar coupling comprises a plurality of oppositely circumferentially magnetized permanent magnets (102) mounted on the driving rotor by polepieces (103) bolted to the rotor body (101). In a synchronous coupling, Fig. 10, one ferromagnetic ring 8 carries a set of teeth 12 and a second ring 9 is provided with a set of teeth 71 of smaller pitch than the teeth 12, there being formed on the driven rotor 4 opposite the teeth 71 a further set of teeth 74 of the same pitch as the teeth 71, the spaces between adjacent teeth 71 and between adjacent teeth 74 being filled by solid or hollow conductors to provide extra synchronizing torque.