MANUFACTURING METHOD OF LAMINATED CORE

PROBLEM TO BE SOLVED: To provide a manufacturing method of a laminated core which eliminates the deformation of a bridge part that is formed between a bored hole (e.g., a magnet insertion hole) and an outer edge during punching of a core piece.SOLUTION: In accordance with the method, a core piece 10 which includes a plurality of bored holes 13 in an outer region in a radial direction and with which a thin bridge part 14 is formed between the bored hole 13 and the outer edge by coining, is formed by punching successively from a thin plate strip material 11 and the punched core pieces 10 are laminated to manufacture the laminated core. The method includes: a first step of performing the coining for forming the bridge part 14 from a lower side; a second step of processing the bored hole 13 after the bridge part 14 is formed; and a third step of punching the core piece 10 from the thin plate strip material 11 by means of a blanking punch 18 and a die 19. 【課題】鉄心片の打ち抜き加工時に抜き孔（例えば、磁石挿入孔）と外周縁との間に形成したブリッジ部の変形を無くした積層鉄心の製造方法を提供する。【解決手段】半径方向外側領域に複数の抜き孔１３を有し、抜き孔１３と外周縁との間にコイニング加工によって薄肉のブリッジ部１４が形成された鉄心片１０を薄板条材１１から順次打ち抜き形成し、打ち抜かれた鉄心片１０を積層して積層鉄心を製造する方法において、ブリッジ部１４を形成するコイニング加工を下方から行う第１工程と、ブリッジ部１４を形成した後、抜き孔１３の加工を行う第２工程と、打ち抜きパンチ１８とダイ１９によって、薄板条材１１から鉄心片１０を打ち抜く第３工程とを有する。【選択図】図１