Abstract: A drill for forming bores in constructional components and including a tubular stem (2; 22; 32; 42) having an axially extending through-channel (3; 23; 33; 43) which opens into at least one suction opening (7; 11; 27; 37; 47), a shank (5) provided at a rear end of the stem for connecting the drill to a drilling tool (M), and a drilling head (8; 28; 38; 48) having lips (9; 29; 39; 49) and formed entirely of a cutting material and substantially butt-joined to the stem (2; 22; 32; 42) at a free front end of the stem (2; 22; 32; 42), with at least one suction opening being formed by a mouth opening of a front channel (12; 26; 36; 46) which is limited, at least partially by a material of the drilling head (8; 28; 38; 48) and a mouth surface of which, at least partially is arranged in a circumferential region of at least one of the stem (2; 22; 32; 42) and the drilling head (8; 28; 38; 48).

Abstract: A percussive blow assisted rotary drill, has an axially extending shank (1) with a leading end face (3) and an axially extending outside surface (2) with helically extending drilled material removal grooves in the outside surface. A hard metal main cutting plate (6) and hard metal auxiliary cutting plates (11) are seated in an axially extending leading end region of the shank and are arranged in an X-shaped pattern. The main cutting plate and auxiliary cutting plates project axially outwardly from the leading end face (3) and radially outwardly from the outside surface (2). The auxiliary cutting plates project axially and/or radially outwardly beyond the main cutting plate and, relative to the rotational direction (R) of the drill, the auxiliary cutting plates and the main cutting plate lagging the auxiliary cutting plates form an acute angle. The main drilled material removal grooves are located upstream, relative to the rotational direction, of the auxiliary cutting plates.

Abstract: A rotary percussion blow assisted drill has an axially extending shank (1) with at least one main helically extending groove (4) in its axially extending outside surface (2) for conveying drilled material along the shank. A cutting plate (6) with hard metal cutting edges (7) is located in a cutting head end region (10) of the shank. The cutting edge (7) of the cutting plate (6) projects axially outwardly from a cutting head end face (3) of the shank (1) and the opposite ends of the cutting plate project radially outwardly from the outside surface of the shank. At least one pin-shaped guide element (11) is embedded into the outside surface (2) in the head end region (10) of the shank.

Abstract: A percussive blow assisted rotary drill includes an axially extending shank (1) with a leading end face (3) and an axially extending outside surface (2) containing a helically extending drilled material removal groove (4, 5). At least one hard metal cutting plate (6) extends across a diameter of the shank and has a base part fixed in a continuous groove (9) in the leading end face (3) of the shank (1). The base part (10) is reinforced by an outwardly extending projection (12) in at least one of its side surfaces extending across the shank diameter. Preferably, the projections forms a part of a circle and are centered between the opposite ends of the cutting plate. The continuous groove (9) has a recess in at least one of its side surfaces shaped to coincide with the shape of the outward projection (12) on the cutting plate. Accordingly, the base part (10) is secured in a positively locked manner and preferably is centered in the leading end face of the shank.

Abstract: A drilling unit is formed of a hollow annular drill bit (1) and a centering drill (2) where the centering drill is a single piece including a chucking shank (2a) and a drill head (2b). A detachable connection is provided between the annular drill bit (1) and the centering drill (2), preferably in the form of a thread (3) whereby the drilling unit can be provided with different diameter annular drill bits (1) and can be adapted to different applications as well as to different power tools presently in use.

Abstract: A tool bit for use in at least one of a drilling and cutting operation is formed of an axially extending carrier member (1) and a cutting member (2). The cutting member (2) has an expansion joint (2a) extending parallel to the axis of the carrier member (1). The expansion joint (2a) is formed by reducing the thickness of the cutting member (2) so that material webs (2b) remain. In the fabrication and formation of the tool bit, the cutting member (2) is a single unit. In the use of the tool bit, due to the expansion joint the cutting member forms individual operating units (2a) affording reduced material expense of the cutting member (2), because of reduced stresses.

Abstract: An arrangement for transmitting torque from a chuck (5) in a manually operated tool to a tool bit (1) having an axially extending chuck section (2) insertible into the chuck. The chuck section (2) has axially extending entrainment faces (31) arranged to cooperate with correspondingly shaped torque transmitting faces (6) in the chuck (5). The chuck section (2) is arranged to cooperate with a device (7) in the chuck for retaining the tool bit and affording limited axial displaceability of the bit. The chuck section (2) is formed with at least one recess (4). The device (7) in the chuck includes a locking element (8) engageable in the recess. The locking element (8) is axially and radially displaceable both to a limited extent and the axial displaceability of the tool bit is possible at least in part, by the limited axial displaceability of the locking element (8).

Abstract: A drilling bit includes a carrier member (3) shaped, for instance, as a hollow annular crown. In such a crown several cutter members (4) are distributed angularly apart around the circumferentially extending leading end of the carrier member. The cutter members (4) project both radially outwardly and inwardly from the wall thickness of the carrier member. A step (S) is formed in the cutter members spaced from the leading end thereof opposite of the drilling direction. The step (S) is located at the trailing end of a region (K) with a continuous reduction in the radial dimension (R) of the cutter member and the radial dimension is further reduced at the step. Due to the further reduction in the radial dimension at the step (S), the length of the cutter member (4) in the drilling direction, causing friction with the wall surface of the borehole to be drilled, is limited after extended use of the drilling bit, so that the drilling bit retains a higher drilling efficiency even after such extended use.

Abstract: A hollow annular drill bit is formed of an axially extending hollow cylindrical carrier member (1) and cutter members (2). The cutter members (2) are secured in recesses (1c) in the carrier member, so that they project axially from and radially inwardly and radially outwardly from the leading end region of the carrier member. The carrier member (1) has increased wall thickness sections enclosing the recesses, whereby sufficiently large connecting surfaces are available for securing the cutter members (2).

Abstract: The tool for a tool holder of hand tools used for chiseling and/or percussion drilling has a chucking shank (9). This chucking shank (9) is provided with two rotary driving grooves (10) which are located diametrically opposite one another and open axially toward the free end of the chucking shank (9). Also, the chucking shank (9) has two diametrically opposite, axially closed locking grooves (11). In order to increase the total working surface decisive for the transmission of torque, two longitudinal grooves (12) are provided which are likewise arranged diametrically opposite one another and open axially toward the free end of the chucking shank (9). The length of these longitudinal grooves (12) exceeds the length of the locking grooves (11). The axes of symmetry (L) of the longitudinal grooves (12) are arranged at an acute angle (a) to the axes of symmetry (V) of the locking grooves (11).

Abstract: The clamping shank (1) of a chisel-cutting and/or percussion boring tool bits has stop faces effective in the axial direction and in the circumferential direction. Entrainment faces (2), open towards a free end of the clamping shank (1) are located upstream of these stop faces in the direction of the cutting area of the tool bits. The radial dimension (r) of the essentially radially extending entrainment faces (2) is greater than their axial dimension (a). In cooperation with an appropriately designed tool bit receptacle, the entrainment faces (2) can carry such a large share of the torque, that the stop faces are effectively relieved or unloaded.

Abstract: A tool bit has an axially extending shank section (1) to be inserted into a chuck in a manually-operated tool. The tool bit has an axially extending working section extending from the shank section. In the end region of the shank section remote from the working section there are first faces (2) acting in the axial direction and second faces (3) acting in the circumferential direction. In addition, the shank section (1) has entrainment faces (4a) spaced axially from the first and second faces toward the working section. The entrainment faces (4a) are located radially outwardly from the first and second faces (2, 3). The entrainment faces (4a) are part of grooves formed by a profiled section of the shank section and the grooves are open in the axial direction toward the first and second faces. The entrainment faces (4a) are radially spaced outwardly from the outer surface of the part of the shank section containing the first and second faces, so that they are able to transmit larger torques.

Abstract: A tool bit shank (11) for percussion drilling or chipping has at least three rotary entrainment grooves (13, 14, 15) extending in the axial direction and at least one locking groove (12) also extending axially. The rotary entrainment grooves (13, 14, 15) open at a free end (16) of the shank (11) so that rotary entrainment members of a tool bit chuck can be inserted axially into the rotary entrainment grooves. The locking groove is closed at its end adjacent the end face (16) to prevent ejection of the tool bit when it is engaged by a locking member of the chuck. To significantly reduce the wear of the tool bit shank and the tool bit chuck, the rotary entrainment grooves (13, 14, 15) are arranged in sequence in the circumferential direction in respect to radially outwardly facing circumferentially extending openings from the largest to the smallest opening.

Abstract: The invention contemplates an improved drill-bit construction wherein the shank by which the bit is clamped is characterized by (a) three angularly spaced grooves which are continuous over their entire length of engageability to the jaws of a multi-jaw chuck, (b) at least one of the grooves being closed at its rear end, (c) the rear end of the closed-end groove is at no greater offset than 5-mm from the rear end of the bit, and (d) the diameter of the cutting part of the bit shank is greater than the diameter of the clamping part of the shank, to an extent which at most results from shaped formation of the chip-removal groove.

Abstract: 1. A tool holder for drilling machines, drilling devices as well as drills and drill sets.2. The tool holder, which is developed as a multi-jaw chuck, has a cylindrical bore 326 into which, with maximum opening of the holder, the jaws 322 engage, or the driver of each jaw has an end surface 416 which faces the hollow space of the holder and is interrupted by an axially extending rib 320.The drilling device has a tool holder developed as multi-jaw chuck and a drill whose chucking shank is guided axially in the hollow space of the holder and has grooves for the engagement of radially inner parts of the jaws of the multi-jaw chuck.In its chucking shank the drill has axially extending grooves for the engagement of the jaws of a multi-jaw chuck, within the bottom of which grooves, or at least in one of them, there is a trough which terminates at a distance from the rear end surface and is connected with said end surface by an introduction groove whose cross section is smaller than the cross section of the groove.

Abstract: An improved boring tool comprising a longitudinal groove in its shaft and a two-armed tool within the groove is provided for boring an enlargement within a hole. The two-armed tool has a rear actuating arm and a forward cutting arm and is tiltably supported in the groove for tilting between an ineffective position, in which its actuating arm extends out of the groove for cooperating with the edge of the outer end of the hole, and effective positions in which the cutting arm reaches out of the groove for cutting the enlargement into the wall of the hole when the edge of the open end of the hole forces the actuating arm into the groove.

Abstract: A method of cutting a cast strand into longitudinal sections is disclosed. The method comprises initially severing said strand transversely to form a slab, transporting said slab to a first longitudinal cutting means where it is longitudinally cut. The strand is cut transversely a second time to form a second slab which is transported to a second longitudinal cutting means where it is longitudinally cut.

Abstract: A central pilot shaft having a cutting member at its end protrudes forward rom the axis of a circular bracket disc which has a plurality of cutting members arranged on its periphery. An exhaust channel permits removing fine particles from in front of the bracket disc.

Abstract: An exhaust channel in a rock drilling head of a rotary impact drill has an pening which extends over the front face of the drill shaft and over the adjoining peripheral surface of the drill shaft. Clogging of the exhaust channel is prevented by providing clearances between the forward and peripheral surfaces of the drilling head and the bored hole which are too small to permit the passage of rock particles large enough to block the exhaust channel.

Abstract: A device for longitudinal cutting cast strands is disclosed. Disclosed is a means for transversely severing a strand into slabs, feeding the slabs selectively to a plurality of longitudinal cutting means and longitudinally cutting said slabs therein. Also disclosed is a novel longitudinal cutting means comprising a flame cutter and a cutting point opening in registry therewith.