Fastener having primary and secondary threads
US5779417A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 1997 |
| Grant date | Jul 14, 1998 |
| Priority date | — |
| Expiry date | May 12, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16B39/282
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In a fastener having a head, which may have having torque-absorbing ribs, and a shank, which is unitary with the head and which has a primary thread formation and a secondary thread formation. The primary thread formation, which defines axially spaced threads along a generally cylindrical portion of the shank and along a tapered tip of the shank, has a generally uniform radial dimension along the generally cylindrical portion of the shank. The secondary thread formation, which defines axially spaced threads between some of the threads defined by the primary thread formation, originates at a region spaced axially from the distal end of the generally cylindrical portion of the shank, terminates at the head, and tapers outwardly from the region where it originates toward the head. The secondary thread formation at the region adjoining the head has a radial dimension less than the generally uniform radial dimension of the primary thread formation along the generally cylindrical portion of the shank. The region where the secondary thread formation originates is located between the proximal and distal ends of the generally cylindrical portion of the shank.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.