GB191124776A - Improvements relating to Magnetic Clutches. - Google Patents

Abstract

24,776. Collier, A. T. Nov. 7. Clutches, friction and claw.- Relates to electromagneticallyoperated friction clutches in which one part carries a number of loosely-mounted armatures of small size. The core consists of two sets of plates c, Figs. 2 and 4, with overlapping teeth d, a coil j being placed within the core. The ends of the plates c form poles, coacting with which are armatures o consisting of bars engaging between teeth n, Fig. 6, on a cylindrical part k, and guided radially by pins p. Each of the plates c may have a radial slot to prevent the formation of eddy - currents. The core is carried on a wooden block e, and is secured in place by bolts g and plates f, f<1>, one of which has a boss h secured to the shaft a. The part k is connected to the other shaft b. Spiral springs r encircle the armatures and overcome the effects of centrifugal force. A rheostat is provided in the circuit of the coil j in order that the clutching effect may be made variable. In the form shown in Figs. 7 and 8, the core consists of a series of radial insulated bars a secured on a ring t by an encircling band u. In this case, the armatures o' are arranged radially between teeth on the member k<2>, the outer ends of the armatures engaging a groove v in the member k<2> to prevent radial movement. If desired, the armatures may be so inclined to the axis of the clutch that centrifugal force opposes or assists the action of the magnetic coil. The armatures may be pressed into action by springs. The core-plates may be wedge-shaped and nested together in two series s<1>, s<2> in staggered relation, as shown in Figs. 9 and 11, in this case the armature o acting radially. A positive clutch may be thrown into action when the clutch is fully engaged, in order to avoid consumption of current. The core may be formed of solid metal. The member k, or the part thereof adjacent to the armatures, may be of insulating-material, such as vulcanized fibre, when the clutch is to be used with an intermittent or undulatory electric current. The poles and armatures may be arranged on the surfaces of cones. The driving-faces of the teeth n may be cut away at their inner ends to prevent the formation of ridges by friction with the armature o. The working faces of the armatures may be hardened. The clutch may run in an oil bath or water trough, the coil being suitably protected ; or the electro-magnet or the member k or both may be provided with water jackets to prevent rise of temperature.