Apparatus and methods for limiting movement of gripping members
US9416602B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 2014 |
| Grant date | Aug 16, 2016 |
| Priority date | — |
| Expiry date | Nov 6, 2034 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/07
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An apparatus to limit movement of gripping members relative to an elevator includes a locking arm coupled to the gripping members and a first engagement arm. The locking arm includes a set of teeth disposed longitudinally thereon, and the first engagement arm includes a first set of complimentary teeth configured to engage with the set of teeth of the locking arm. The first engagement arm is moveable between a disengaged position, in which the first engagement arm and the locking arm are relatively moveable, and an engaged position, in which the first engagement arm allows the locking arm to move in a first direction but prevents the locking bar from moving in a second direction by more than a selected distance. The teeth of the locking arm engage the first set of complimentary teeth of the first engagement arm when the first engagement arm is in the engaged position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.