| 摘要 |
<p>1,201,109. Drill jigs. BROWN BOVERI & CO. Ltd. 14 June, 1968 [16 June, 1967], No. 28563/68. Heading B3C. In a drilling device for gun and annular drilling comprising means 19 for supplying a drill 9 with cutting-fluid, a bushing 1 for guiding the drill and means 15 for pressing an end surface 12 of the bushing against a workpiece 8 to reduce or prevent radial deviation of the bushing during drilling, the bushing 1 has a sealing ring surface 10, separate from the end surface 12, engageable with the workpiece to provide a fluid seal therebetween and surrounding the drill. In operation of the drilling device shown the bushing, which incorporates a milling cutter 12, is pressed against the workpiece 8 by a pressure fluid piston 15, and rotated by gears 7 and driving pins 2 until a groove 13 is cut and the sealing ring 10 engages the workpiece and the resistance to rotation increases. The downward pressure on the piston is increased and the drill rotated, cutting fluid passing in the direction 20 through the drill tube 19 and drill 9 and carrying chippings away through the annular passageway 22 between the drill tube and the inside wall 16 of the piston 15. In an alternative drilling device the milling cutter is replaced by ring segments, annular ring-shaped supporting surfaces or individual radial surfaces which can be provided with projecting ribs or edges, engageable with a workpiece, which may have a curved surface, in its elastic range. The drill tube (39) (Fig. 2, not shown) may have a profile permitting cutting-fluid to pass through it and chips to move along external U-grooves of the drill tube.</p> |
