GB978163A - Improvements in or relating to rollers, calenders and like cylindrical articles - Google Patents

Abstract

978,163. Induction heating. BEANWY ELECTRIC Ltd. June 6, 1963 [March 5, 1962], No. 8423/62. Heading H5H. An inductively-heated roller comprises a magnetizable cylinder 1 and endplates 2, 3 rotatable on bearings 6 about a fixed tubular shaft 9. Secured to the shaft are discs 11-14, consisting of brass, aluminium or iron castings, having radial slots 16 in which lie magnetizable bars 18. The bars consist of a stack of laminations and extend between the endplates 2, 3 leaving air gaps of from one-thirty-second to one-nineteenth of an inch. The bars are surrounded by a copper coil 22 wound on an asbestos or fibre-glass former 21. It is stated that the brass can be formed of sintered iron or a mixture of thermosetting plastic and powdered iron. The bars are six in number and mounted in equi-spaced slots in the discs. A thermo-couple senses the cylinder temperature and controls an alternating-current mains supply to the coil through an undisclosed arrangement. The connections to the coil and thermocouple are made through the tubular shaft. It is stated that more than one coil can be employed and that with one coil the spacing of turns can be chosen to allow for loss of heat through the end-plates. It is also stated that the coil and associated core structure can be made rotatable, the supply being fed in through slip rings.