Magnetic head core mfr. from stack of laminations - involves linear machining of patterns from adhesively bonded and rolled sandwich of permeable and non-permeable layers

摘要

A stack (22) of thin layers (23-25,27) of material with magnetic permebility is assembled between rollers, with inter-leaved spacing layers (28-30). From this stack (22) a number of complete cores (39-41) or half-sections (39a,39b) are obtained by machining along lines (31-38) drawn in appropriate positions on the top layer (23) and down the sides and ends of the stack. The isolating layers (28-30) may be bonded adhesively to the respective underlying magnetically permeable layers (24,25,27) before being rolled into the stack, height of which corresponds approximately to the magnetic track width or height. ADVANTAGE - Does not impose undue stress on material during machining, which is performed pref. by wire spark erosion, magnetic properties of metal are not degraded.