Dowel hole drilling machine

摘要

A machine frame (1) of a dowel hole drilling machine has a workpiece support (2) and a drilling unit (13) which is mounted on guides (6, 7) of the machine frame (1) so as to be vertically movable relative to the workpiece support (2) and which possesses a large number of drilling spindles (22) arranged at a distance from one another corresponding to the dowel holes to be produced and driven jointly by a drive motor (28) and belt (wound-round) drives. The drilling unit (13) is provided with at least one separate additional unit (39) which has drilling spindles which are integrated in the drilling unit (13), is driven in dependence on the drilling unit (13) and whose drilling-spindle spacing is less than the smallest-possible spacing between the other drilling spindles (22). The vertical movement of the drilling unit (13) is effected by means of lifting beams (6) via pressure medium-actuated push rods (9) and interacting pressure pieces (10) and wedge-shaped run-on pieces (11). Mounted in the machine frame (1) is a suction channel (51) having connection openings to which in each case one connection elbow (53) is connected, the latter being connected via a flexible hose pipe (54) to the drilling unit (39) in order to cool the latter. A shaving-removing band (63) driven intermittently in dependence on the lifting beam vertical movement is mounted beneath the lifting beams (6). <IMAGE>