Fastener screw thread and pilot to avoid cross threading
US4981406A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 5, 1988 |
| Grant date | Jan 1, 1991 |
| Priority date | — |
| Expiry date | Dec 5, 2008 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B35/047
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A screw or bolt has a conventional threaded shank and a tapered pilot or lead end for easy entry to a threaded receptacle or nut. A pilot lead extends axially from the end of the shank. In one form, the pilot is cylindrical having an axis that either intersects or is parallel to the axis of the shank. Partial threads extend around the portion of the periphery of the pilot and an unthreaded transition surface angularly spaced from, transversely opposite, the partial threads extends to the outer surface of the shank. In another form, the pilot is elliptical having partial threads extending over a portion of its periphery and an unthreaded surface transversely opposite the pilot threads.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.