GB568409A - Improvements in and relating to electro-magnetic clutches or brakes - Google Patents

Abstract

568,409. Friction clutches and brakes. SELF-CHANGING GEAR CO., Ltd., WILSON, A. G., and MILLER. A. A. March 1, 1944, No. 1669/43. [Class 80 (ii)] [Also in Groups II and XXXIV] In an electromagnetic clutch or brake in which an electromagnet attracts its armature, the 'frictional grip between these two parts providing a driving or braking torque, the whole or part of the magnet c or armature d is of cast iron, having a graphitic carbon content of at least 1.75 per cent and a combined carbon content of not more than 0.83 per cent. The material may be sprayed on to the rubbing surfaces. Alloying agents such as nickel may be' combined with the iron. Thus, wear on the rubbing surfaces is reduced. Wear-resisting inserts of non-magnetic material, such as phosphor bronze or non-magnetic iron, may be inlaid flush in the rubbing surfaces. Such inserts may be rings h, h<2>. Alternatively, the rings h<2> may be replaced by plugs. To assist the separation of the surfaces, a resilient ring, e.g. of corrugated form, may be mounted between the armature and pole faces. Specification 521,351, [Group XXXIV]. is referred to.