摘要 |
A vehicle carries an extensible boom rotatable about a horizontal and vertical axes. The end of the boom arm carries a universally articulated rock breaking tool mounting means. The vehicle has two ground engaging sole plates carrying hydraulic rams for raising the remainder of the vehicle from the floor to enable the vehicle to be advanced by a pair of advancing rams which are independently operable to enable the vehicle to be steered. The raising rams act on pivotal links which have rollers at their free ends to bear on an underneath surface of the chassis. The sole plates are in open-bottomed channel-like parts of H-section beams whose upper parts are sealed and act as sumps for hydraulic fluid and as radiators to dissipate heat. Control of the boom is from either side of the vehicle by means of a changeover valve. Control of advancing and reversing movement of the vehicle is from the front or rear of the vehicle. |