Screw for contaminated pre-tapped holes
US5000638A · kind A · utility
20Cited by
9References
1Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1989 |
| Grant date | Mar 19, 1991 |
| Priority date | — |
| Expiry date | Dec 21, 2009 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B39/30
- 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.