CORE FOR FLAT MOTOR AND MANUFACTURE THEREOF

摘要

PURPOSE:To obtain a core having the prescribed characteristics without waste of a material by forming a blank added with the prescribed compressing margin at an arm portion of an iron sintered alloy, and densifying the arm to the prescribed sintering density. CONSTITUTION:A plurality of arms 2 are projected toward the center from a ring-shaped body 1 which operates as a function of a yoke and toothed poles 3 are formed at the end of a core. Coils 4 are mounted on the arm portions of the arms 2. The arm portions are formed thinly to be contained as the entire coil in the core. The core is made of an iron sintered alloy, the arm portions are densified to the prescribed sintering density to enhance the magnetic flux density of the portion higher than the pole. Thus, the core having the prescribed shape and characteristics is manufactured without waste of a material.