| 摘要 |
The invention provides an apparatus (2) for imparting relative movement between an oscillating member and a rail (4). The apparatus (2) comprises a support (6) in the form of a housing providing a fulcrum (8) and biasing mea ns (10) to bias a lever (18) about the fulcrum (8). The lever (18) has an engaging formation (20) spaced apart along its length from the fulcrum (8). The engaging formation (20) is configured to selectively grip and release th e rail (4). In one embodiment of the inventions application, the housing (6) i s secured to a percussion rock drill and the rail (4) secured in a position to allow drilling as desired. The lever (18) supports the rock drill above the rail (4). The oscillation of the drill and housing causes the lever (18) to pivot about the fixed fulcrum (8) against the bias of the biasing means (10) . This disengages the grip of the engaging formation (20) and the drill is advanced along the rail (4). The mechanism is based on a friction drive on a rail (4) provided by applying force to an over center cross-corner locking lever (18) in one direction to produce a friction lock on the rail (4) and then applying force in the return direction to make the lever (18) slip alon g the rail (4). In this way the lever (18) forms a walking thrust arm for an oscillating member.The invention also provides for the same mechanism to be used to effect reverse movement of the drill along the rail (4). The rail (4 ) need not be straight and the mechanism can also be used to move a rail (4) i n relation to an oscillating member. |
