Thread structure for percussion rock drilling
US4687368A · kind A · utility
27Cited by
10References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 3, 1986 |
| Grant date | Aug 18, 1987 |
| Priority date | — |
| Expiry date | Apr 3, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T403/5746
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A thread structure for interconnecting two elements in a percussion drill string comprising an interior cylindrical thread and an exterior cylindrical thread. The threads have abutting flanks which are straight along their abutting contact portions. The clearance (a) between the bottom portion of the exterior thread and the crest portion of the interior thread is large enough to ensure that contact does not arise at said clearance when the threads are worn.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.