FLEXIBLE EXTERNALLY TOOTHED GEAR FOR STRAIN WAVE GEARING AND METHOD FOR MANUFACTURING SAME

摘要

A method for manufacturing a flexible externally toothed gear includes: a first step (ST1) for producing a primary molded article by performing near-net-shape plastic working on a material comprising a nickel-free low-alloy steel having a silicon content of 1.45-1.5 wt %; a second step (ST2) for martempering the primary molded article; a third step (ST3) for producing a secondary molded article from the primary molded article; and a fourth step (ST4) for shot-peening the secondary molded article to change the surface portions of the tooth part and other parts to martensite. A flexible externally toothed gear can be obtained in which the surface hardness is kept within a prescribed range and the fatigue strength and abrasion resistance are high.

主权项

1. A method for manufacturing a flexible externally toothed gear for a strain wave gearing, the method comprising:
a first step for producing a cup-shaped or top-hat-shaped primary molded article approximating a shape of the flexible externally toothed gear for the strain wave gearing by performing near-net-shape plastic working on a material comprising nickel-free low-alloy steel having a silicon content of 1.45-1.5 wt %; a second step for martempering the primary molded article; a third step for producing a secondary molded article by performing turning and gear-cutting on the martempered primary molded article, the secondary molded article having a diaphragm part and a tooth part formed thereon; and a fourth step for shot-peening the secondary molded article to change a metal structure of a surface layer portion of the tooth part and the diaphragm part to martensite.