Retaining device
US6305649A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jun 3, 1999 |
| Grant date | Oct 23, 2001 |
| Priority date | — |
| Expiry date | Jun 3, 2019 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/102
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A retaining device to prevent linear movement of an elongate member (10) in the downwards direction comprising a plurality of segmental ball slips (14) surrounding the member (10) and removably introduced into a tapered opening in a supported bushing (13), each ball slip (14) including a ball cage (18) having balls (20) and ramps (21) and a spring (19) urging the ball cage downwardly and thus the balls inwardly to grip the elongate member with a smooth rolling action preventing surface damage to the elongate member. The ball slips (14) may be hinged together around the elongate member (10) and may removed manually or by power operated means at (22).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.