| 摘要 |
A post driver 5 comprises a device 60 for holding a drivable member 55 and at least one driver or ram 75 for moving the holding device between a first (operational) position and a second (storage) position. The drivable member typically comprises a rock spike, but could be an auger, post, pile or anchor. The holding device may comprise a collar or sleeve formed from at least two separable or hinged parts. The driver or ram may be powered hydraulically, pneumatically, electrically or magnetically. The holding device may comprise at least one arm pivotally mounted on a mast of the post driver and may be supported by a guide rail or track. The mast may include a weight or hammer. |
