Patent · US Expired

Forging device for crown-shaped helical gear

US6178801A · kind A · utility

7Cited by
1References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 16, 1999
Grant dateJan 30, 2001
Priority date
Expiry dateMar 16, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49474
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

Crown twist forming teeth (14) are formed on the inside circumferential surface of a finishing die (13) with the thickness of each teeth being thinner in the middle part than toward both ends in the axial direction. The finishing die (13) is fitted for axial sliding in the axial direction in the axially central part of a die holder (11) through taper surfaces (12a, 13a) diminishing from its one end to the other. A half-finished work (35, 35') with its outside circumferential surface having rough-formed twist teeth is brought into screw engagement with the finishing die (13). A first punch (25) for pressing the half-finished work (35, 35') from one axial end toward the other, and a second punch (26) for pressing the finishing die (13) from one axial end toward the other are provided. A rotary device (30) is provided to rotate the die holder (11) in the direction opposite the direction in which the half-finished work (35, 35') is rotated with the finishing die (13) when the first and second punches (25, 26) are working under pressure. This makes it possible to form with a forging device a helical gear having crown-formed twist teeth, with each tooth being thicker in its middle part i…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.