Gravity-steered grapple
US5244338A · kind A · utility
Inventor
Key dates
| Filing date | Mar 26, 1992 |
| Grant date | Sep 14, 1993 |
| Priority date | — |
| Expiry date | Mar 26, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB66C1/28
- WIPO fieldHandling
- WIPO sectorMechanical engineering
Abstract
A gravity-steered grapple is created by retrofiting the boom plate of an excavator which has a longitudinally rotatable boom. The grapple includes a freely-turning, swivel joint with an axis of rotation which is offset from the center of the grapple jaws so that the center of mass of the load is likewise offset. By manipulating the angle of the boom plate with existing operator controls, the load can be steered about the swivel joint controllably through a horizontal 360-degree angle. The grapple also includes a jaw safety clamp which is movable between lock and release positions. The clamp is self-actuating and is moved into the lock position when an extension of the clamp contacts the load as the grapple is raised. The grapple is particularly useful in lifting and placing modular highway barriers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.