Post puller and related method using a lifting action of a working machine to actuate cam-shaped grippers of the post puller
US9624690B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Feb 11, 2015 |
| Grant date | Apr 18, 2017 |
| Priority date | — |
| Expiry date | Aug 23, 2035 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE04H17/265
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A post puller features a lifting member that is slidably disposed on a guide shaft and attachable to a lifting arrangement of a working machine. A pair of movable grippers are pivotally supported on the guide shaft at a fixed position therealong, and a pair of links are pivotally connected between the lifting member and the grippers. With a web or flange of the post received in a space between inner ends of the movable grippers, raising of the lifting member by the working machine lifts the outer ends of the movable grippers via the pair of links, thereby lowering inner ends of the grippers into closer proximity to one another to grip the web or flange of the post between the grippers. With the post gripped in this manner, further raising of the lifting member by the working machine pulls the post from the ground.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.