Engine speed limiter for a hoist
US7004456B2 · kind B2 · utility
14Cited by
25References
18Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 3, 2002 |
| Grant date | Feb 28, 2006 |
| Priority date | — |
| Expiry date | Oct 3, 2022 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B41/0021
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A mobile service rig for wells includes a hoist powered by an internal combustion engine. In response to the hoist exerting a predetermined lifting force, the lifting force is limited by automatically limiting or reducing the speed of the engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.