Patent · US Expired

Method and apparatus for hardening gears

US4855551A · kind A · utility

15Cited by
12References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1988
Grant dateAug 8, 1989
Priority date
Expiry dateAug 8, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D9/32
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Method and apparatus for hardening the outwardly facing teeth surfaces of a gear is disclosed. First and second induction heating coils with power sources controlled by an appropriate microprocessor preheat the gear when in the first coil at precisely controlled cycles to generate an unstable circular band of high temperature positioned radially inwardly from the tips of the gear. Before the band can dissipate, the microprocessor actuates an appropriate drive to locate the gear in the second coil energized by an appropriate power source to impart a high skin temperature to the teeth. A liquid spray quench in the second coil is immediately actuated to effectively quench the gear. By sizing the cycles, the gear teeth are rapidly hardened at minimal power levels.

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