GB1146871A - Improvements in or relating to electric induction units - Google Patents

Abstract

1,146,871. Induction heating units. BEANWY ELECTRIC Ltd. 30 March, 1966 [30 Dec., 1965], No. 52768/64. Heading H5H. A 1.f. induction heater comprises a plurality of multiturn coils 1 each mounted around a straight core 3 of flat magnetizable laminations extending between and at right-angles to two parallel magnetizable end plates 4, the core ends projecting from the coil and secured or close to the end plates. The coil comprises copper wire sheathed in glass fibre, asbestos or mica wound on an asbestos cement spool 2 supported by a steel core 3 of square cross-section. A number of assemblies are grouped around the barrel or part of the barrel of an injection moulding machine between annular iron or steel end plates 4 each in two or more segments clamped to the barrel and several such groups may be arranged along the barrel. The plates contain radial slots 8 into which the ends of each core fit and are secured by bolts 9 to form closed magnetic loops consisting of the core 3, plates 4 and the barrel 5. A non-magnetizable strip 10 extends between the plates 4, as shown, or between the barrel and the coil defining a passage for cooling air. Thermocouples sense the barrel temperature. The heaters may be mounted on flat articles or on spider mountings within a rotating drum.