Toggle actuated underreamer
US4023629A · kind A · utility
1Cited by
2References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 25, 1976 |
| Grant date | May 17, 1977 |
| Priority date | — |
| Expiry date | Jun 25, 1996 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B10/32
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An underreamer includes a housing and a plurality of underreamer doors, each including a toggle mechanism for selectively extending and retracting the doors. Upon activation of the toggle mechanism thereby extending the doors, the doors are pivoted outwardly from the housing and the tops of the doors are simultaneously moved downwardly. In this manner the overall vertical height of an underreamer adapted to form a given diameter excavation may be substantially reduced.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.