GB1209535A - A linear induction motor - Google Patents

Abstract

1,209,535. Linear motors. LINEARA A.B. 20 June, 1968 [29 June, 1967], No. 29387/68. Heading H2A. A linear polyphase induction motor comprises a number of substantially identical, separate, ferro-magnetic, toothed primary member core parts, each part having disposed around its teeth the coils which together form one phase winding, the separate parts being mounted with their toothed surfaces adjacent one another, leaving an air gap in which a conductive secondary member is movably mounted, the teeth on the different primary member parts being out of alignment. The two-phase linear motor shown comprises separate ferromagnetic core parts 12A, 12B carrying coils 10A, 10B on individual teeth 13A, 13B, the coils on each core part being connected in series to a single phase source 7, the coils 6A being supplied through a phase splitting capacitor 9. A conductive, non-magnetic, e.g. copper or aluminium, secondary member 2 is mounted in the air gap between the parts 12A, 12B, and 12A is movable relative to the fixed part 12B by means of a nut and bolt arrangement, 19, 25, thus allowing relative displacement of the teeth on the two parts. The core slots are filled with an insulating compound and the core parts are mounted in a good thermally conductive, e.g. aluminium, casing 14A, 14B. A three-phase motor having three separate core parts displaced 120 degrees with respect to each other on the prmiary member and having a three-armed secondary member is described with reference to Fig. 3 (not shown).