Abstract: The invention concerns a hard-metal cutting tip for use on a drill, particularly on a rock or concrete drill, including a drill point (3) extending through an axis of rotation of the drill, primary cutting edges (6) that slope downwardly on both sides, each composed of a primary land (4) and a primary flank (5), the primary flank (5) forming at the primary cutting edge (6) a primary lip clearance angle (14) with a plane perpendicular to the axis of rotation. To provide a hard-metal cutting tip that possesses high cutting, feed, bending and breaking strength and wear resistance, especially at its outer regions subjected to high peripheral speeds, the hard-metal cutting tip is realized such that the primary lip clearance angle (14) formed at the primary cutting edge (6) decreases with increasing distance from the drill point (3).

Abstract: A device for securing a holder to a bore support formed with an undercut blind bore has a sleeve-like plug and a bolt received therein. The plug is formed with a central axis-defining passage having a smooth inner wall, a plurality of axially extending and radially throughgoing slits open at an inner end of the plug and defining a plurality of axially inwardly extending and radially deflectable tongues, and an annularly continuous outer portion from which the tongues extend. The bolt has a smooth outer surface and is shaped and dimensioned to fit complementarily into the passage with outward deflection of the tongues. The bolt and passage are of generally the same axial length so that when fully inserted in the passage the bolt is flush with the outer portion.

Abstract: Mounting (10) for facing panels, which have several securing bolts (12) projecting on the wall side with panel-parallel securing collars (13), behind which engages at least one wall anchor (15) which is anchored to the wall with anchor bolts (16).In order to fasten the facing panel to the wall with simple means and in a simple way, the mounting is designed so that the securing bolts (12) are suspended with their panel-parallel securing collars (13) in at least one hook-like wall anchor (15), which prior to the mounting of the facing panel (11) to the wall is detachably connected with the securing bolt (12).

Abstract: Drilling apparatus (50) for producing drilled holes with undercuts, with a drill (15), the drill shank (19) of which has a side cutting edge (14) protruding radially beyond the periphery (18) of the drill shank, and, on its circumference, opposite the side cutting edge (14), has a flattening, which makes possible the insertion of the side cutting edge (14) into the drilled hole, and the drill shank (19) of which is firmly connected with a connecting coupling (20), which is disposed in an articulated fashion between the drill (15) and a drill driving mechanism, permits wobbling motions of the shank as the drill (15) is rotating and has a drill shank-side coupling (29) with an axially movable indentor (85), which can be supported on an inclined plane (17) of a coupling (29) connected with the drill shank (19), which inclined plane (17) brings about the radial advance of the side cutting edge (14).

Abstract: A bit assembly for undercutting a blind bore extending along a bore axis between an open outer end and a closed inner end and having a substantially cylindrical wall of a predetermned diameter centered on the bore axis and extending between the ends comprises a pusher body normally seated in the closed inner end of the bore and having an outwardly turned camming surface inclined to the bore axis, and a bit having a shaft extending along a longitudinal bit axis and having an inner end, an outer end, and a pair of longitudinally extending sides terminating at the inner end. One of the sides is at least partially cylindrical and centered on the bit axis and the inner end is formed with a camming surface engageable with the camming surface of the body and inclined to the bit axis. A blade fixed permanently and stationarily on the inner end projects radially from the one side of the shaft, the other side being cut back toward the bit axis.