MANUFACTURING METHOD OF GEAR

To accurately manufacture a gear in which a plurality of toothed wheels are arranged.SOLUTION: A manufacturing method of a gear includes: a raw material preparation step of preparing a small-diameter gear raw material and a large-diameter gear raw material; a positioning part forming step of forming a positioning part 32ba at the small-diameter gear raw material; a small-diameter toothed wheel part forming step of forming a small-diameter toothed wheel part 32a at the small-diameter gear raw material with the positioning part 32ba as a reference; a first engagement part forming step of forming an outside diameter spline to the small-diameter gear raw material with the positioning part 32ba as a reference; a second engagement part forming step of forming an inside diameter spline at the large-diameter gear raw material; a large-diameter toothed wheel part rough-processing step of applying rough processing of a large-diameter toothed wheel part 32c to the large-diameter gear raw material with the inside diameter spline as a reference; an engagement step of forming an engagement body by making the inside diameter spline of the large-diameter gear raw material and the outside diameter spline of the small-diameter gear raw material engaged with each other; and a large-diameter toothed wheel part finish processing step of applying the finish processing of the large-diameter toothed wheel part 32c to the engagement body with a small-diameter toothed wheel part 32a as a reference.SELECTED DRAWING: Figure 2 【課題】複数の歯車が設けられたギアを高精度に製造する。【解決手段】ギアの製造方法は、小径ギア粗材及び大径ギア粗材を準備する粗材準備工程と、小径ギア粗材に位置決め部３２ｂａを形成する位置決め部形成工程と、位置決め部３２ｂａを基準として小径ギア粗材に小径歯車部３２ａを形成する小径歯車部形成工程と、位置決め部３２ｂａを基準として小径ギア粗材に外径スプラインを形成する第１係合部形成工程と、大径ギア粗材に内径スプラインを形成する第２係合部形成工程と、内径スプラインを基準として大径ギア粗材に大径歯車部３２ｃの荒加工を実施する大径歯車部荒加工工程と、大径ギア粗材の内径スプラインと小径ギア粗材の外径スプラインとを互いに係合させて係合体を形成する係合工程と、係合体において、小径歯車部３２ａを基準として大径歯車部３２ｃの仕上げ加工を実施する大径歯車部仕上げ加工工程と、を含む。【選択図】図２