METHOD FOR JOINTING ELECTRICAL MACHINE FRAME WITH WOUND STATOR STACK Russian patent published in 2001 - IPC

FIELD: electrical engineering; manufacture of electrical machines, mainly induction motors. SUBSTANCE: method involves frame heating and press-fitting of wound stator stack into hot frame. Novelty is that prior to heating frame is placed in centering facility mounted on upper tier of two-tier table of induction heating installation coaxially relative to one of fixed lower circuits of split magnetic core of heating-installation inductor followed by dropping one of circuits of upper movable part of split inductor core into frame and jointing other circuit of upper movable part of split inductor core with other circuit of its lower part, whereupon electric current is passed through both inductor coils; inductor used for the purpose has length of each circuit in upper movable part of its core greater than that of circuit coaxial to it in lower fixed part of split core by at least 0.7 of frame height and not over frame height; frame is heated for 1.0-1.5 minutes to 90-130 C followed by disconnection of induction heating facility; then frame heated to mentioned temperature is mounted on press table whereon wound stator stack is held in position on expanding mandrel with stator leads being brought inside; after that frame is press-fitted onto wound stator stack; then frame together with wound stator stack press-fitted into it is removed from expanding mandrel and stator leads are brought outside through frame bore. EFFECT: enhanced labor productivity, reduced power requirement, improved quality of connections which increases service life of machine. 3 cl, 6 dwg