Patent classifications
B23G2210/44
Threaded coupling for percussion drill bit
An internally threaded bit for percussion drilling is provided, which has thread roots wider than the thread crests. A single drill bit, configured according to the present invention, can be connected to a variety of rods, having differing crest widths in their male threads. The invention enables the service life of the rods to be optimized to suit the drilling conditions at hand, without the need to manufacture and keep in inventory a correspondingly large variety of drill bits. The bit of the invention exhibits a reduced rate of ringing off, and can accept drill rods having a range of crest widths.
THREADED COUPLING FOR PERCUSSION DRILL BIT
An internally threaded bit for percussion drilling is provided, which has thread roots wider than the thread crests. The bit exhibits a reduced rate of ringing off, and can accept drill rods having a range of crest widths.
Method for producing a tapped bore and tap drill bit
A method for producing a tapped bore in a workpiece with a tap drill bit, which, at its drill bit tip, has a primary cutting edge and a thread profile trailing in a tap drilling direction. The method has a tap drilling stroke, in which the tap drill bit is driven into the workpiece with a tap drilling advance in the tap drilling direction and at a tap drilling rotational speed synchronized therewith, and the tool-primary cutting edge produces a core-hole bore, and the thread profile of the tool bit forms an inner thread at the inner wall of the core-hole bore. In the tap drilling stroke, shavings are produced, which are conveyed in a shavings discharge direction, which is oppositely directed to the tap drilling direction, out from the tapped bore and collide here with thread flanks of the inner thread that face the shavings that are discharged.
METHOD FOR PRODUCING A TAPPED BORE AND TAP DRILL BIT
A method for producing a tapped bore in a workpiece with a tap drill bit, which, at its drill bit tip, has a primary cutting edge and a thread profile trailing in a tap drilling direction. The method has a tap drilling stroke, in which the tap drill bit is driven into the workpiece with a tap drilling advance in the tap drilling direction and at a tap drilling rotational speed synchronized therewith, and the tool-primary cutting edge produces a core-hole bore, and the thread profile of the tool bit forms an inner thread at the inner wall of the core-hole bore. In the tap drilling stroke, shavings are produced, which are conveyed in a shavings discharge direction, which is oppositely directed to the tap drilling direction, out from the tapped bore and collide here with thread flanks of the inner thread that face the shavings that are discharged.
Thread forming tap
A thread forming tap including a complete thread portion and a leading portion is to be screwed into a prepared hole provided in a workpiece so as to cause an inner circumferential surface of the prepared hole to be plastically deformed for thereby forming an internal thread corresponding to the external thread provided in the complete thread portion. A screw thread of the external thread has a leading flank and a trailing flank, which are to be positioned on a front side of the trailing flank and on a rear side of the leading flank, respectively, when the thread forming tap is screwed into the prepared hole. The screw thread is shaped such that, in the leading portion, an indentation depth into the workpiece made by the leading flank is smaller than an indentation depth into the workpiece made by the trailing flank.