Patent · US Expired

Screw for contaminated pre-tapped holes

US4973209A · kind A · utility

33Cited by
12References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 1985
Grant dateNov 27, 1990
Priority date
Expiry dateMar 28, 2005

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16B35/044
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A locking screw having a head at one end, a special entry portion at the other end, and a trilobular shank portion extending from the entry portion toward the head. The screw is further characterized in that the thread profile is of a double angle configuration symmetrical about an axis perpendicular to the longitudinal axis of the screw. The entry section is tapered and is formed with a series of truncations which serve to clear progressively a contaminating coating in an internally threaded workpiece, such as a nut, when the screw is threaded therein.

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