Patent · US Expired

Low-torque nuts for stator core through-bolts

US4810919A · kind A · utility

13Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 16, 1987
Grant dateMar 7, 1989
Priority date
Expiry dateNov 16, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49009
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for compressing a stator core assembly of an electric generator having a plurality of stacked punchings positioned between opposing compression plates. A through-bolt is passed through an aperture drilled through the stacked punchings, and a tensioning nut threaded onto one end of the through-bolt. A thrust nut is threaded onto a second end of the through-bolt, thereby compressing the punchings between the tensioning nut and a thrust nut. The tensioning nut is fixed to the through-bolt so as not to be removable. The punchings are compressed by external means and then the thrust nut is tightened against the plate and peened to remain in position. Final tensioning and retensioning is provided by a plurality of set screws circumferentially placed about the thrust nut and extending parallel to the through-bolt. The set screws may be turned, cooperating against one of the compression plates to exert compressive force on the punchings. The set screws may utilize nylon inserts to prevent loosening. The utilization of the unique thrust nut with set screws allows the punchings to be retensioned after installation without requiring utilization of large tools to turn th…

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