JPS573543A - Coil of step motor for time piece - Google Patents

Abstract

PURPOSE:To make an insulating tape and an insulating paint film to needless and to contrive to reduce cost and to miniaturize a coil of step motor for time piece by a method wherein the corner parts of a coil core are rounded, an insulating lubricant is coated on the coil core and a coil wire is wound around thereon. CONSTITUTION:The corner parts of the coil core 1 are rounded 7. When the coil wire 5 is to be wound after a sheet 4 for terminal electrode and a spool 3 are fitted up to the coil core 1, after the insulating libricant 6 is coated on the surface of the coil core 1, the coil wire 5 is wound immediately. Accordingly because the coil core 1 can get along without providing the insulating sheet and the insulating paint film on the surface, the coil can be manufactured economically and can be miniaturized as much volume corresponding to thickness of the insulating sheet, etc. Moreover because the interval between the coil wires 5 and the coil core 1 becomes small, efficiency can be enhanced and the life of a cell can be enlarged.