Abstract: A drilling tool for machining structural components made of a titanium alloy includes: a support, which extends along an axis of rotation in the axial direction, the support having an end face with a receptacle disposed centrally therein; a plurality of cutting inserts inserted at the end face in a manner that forms a flat drill, each cutting insert having an active insert cutting edge extending transversely to the axial direction; and a drilling tip disposed in the receptacle and having at least two tip cutting edges, the tip cutting edges extending outward from the axis of rotation and being adjoined in each case by at least one active insert cutting edge.

Abstract: A drill bit for drilling a borehole in earthen formations comprising a bit body having a bit axis and a bit face. In addition, the drill bit comprises a primary blade extending radially along the bit face, the primary blade including a cutter-supporting surface that defines a blade profile in rotated profile view extending from the bit axis to an outer radius of the bit body. The blade profile is continuously contoured and includes a plurality of concave regions. Further, the drill bit comprises a plurality of cutter elements mounted to the cutter-supporting surface of the primary blade. Each cutter element on the primary blade has a forward-facing cutting face with a cutting edge adapted to penetrate and shear the earthen formation.

Abstract: A drill, which is used in a hammer drill for drilling holes in stone, concrete and the like, includes a one-piece drilling head (10, 20, 30) formed of a hard material and provided, at its first end (5), with at least one main bit having a tip (4) and at least one cutting structure (3) integral to the one-piece drilling head (10; 20; 30), and at a second end (6) located opposite the first end (5), with a bottom surface (7) for the mounting the drilling head (10; 20; 30) on the drill stem (8), and having a plurality of axially extending through-grooves (11; 21; 31) for removing drillings produced during a drilling process and having a cross-section which increases, at least regionwise, in a direction toward the bottom surface (7) of the drilling head (10; 20; 30).

Abstract: A drill bit of the present invention is intended to stably perform drilling by lessening a great change in a drilling condition and to avoid reduction of a drilling efficiency even when large chip lumps are generated. In the drill bit, the main cutting blades have main cutting edges each structured such that an inner end thereof is located at the rotation center of the drill and an outer end thereof is located on an outer periphery of a rotation trace of the cutting blades, and the sub cutting blades have sub cutting edges each structured such that an inner end thereof is located to be spaced radially outward apart from the rotation center and an outer end thereof is located to be spaced radially inward apart from the outer periphery of the rotation trace toward the center of rotation.

Abstract: A rock drill bit for percussive drilling includes a front face which has radially outer and inner portions. Fluid channels are disposed in the head portion in communication with the inner portion of the front face. The inner portion of the front face carries a plurality of front buttons. The outer portion comprises circumferentially spaced steel portions which are axially raised relative to the inner portion. Each raised portion carries one or two peripheral buttons located radially outwardly of an imaginary circle which intersects at least two of the front buttons and at least two of the flushing channels. The imaginary circle is arranged coaxially relative to the center axis.

Abstract: A drill head for rock drilling comprising cutting edges (1) made of hard material, which is detachably connected axially, over a bearing surface (3), with a drilling shaft (4) with at least one radially projecting driver blade (5a, 5b, 5c) by a bayonet-type connection slot (6a, 6b, 6c), wherein at least one connection slot (6a, 6b, 6c) is present, which forms two axially opposing undercuts (7a, 7b), within which the driver blade (5a, 5b, 5c) has limited axial movement.

Abstract: A drill bit that has a drill bit body with a side wall and opposite ends. A distal one of the opposite ends of the drill bit body receives a cutting insert. The drill bit body contains at least two helical debris ports in the side wall thereof. The drill bit body further contains a helical scallop that corresponds to each one of the helical debris ports. Each one of the helical scallops surrounds so as to define the periphery of its corresponding one of the helical debris ports.

Abstract: A rotary drill bit for penetrating earth strata wherein the drill bit includes a drill bit body that has an axial forward end. The drill bit body has a hard insert, which is preferably monolithic, that is affixed to the drill bit body at the axial forward end thereof. The hard insert presents at least three discrete leading cutting edges for cutting the earth strata. Each cutting edge is stepped.

Abstract: A center vacuum rotary drill bit including a rotary drill bit body and an insert. The bottom surface of the slot has a projecting key that cooperates with a depression keyway of the insert. Generally vertical sidewall surfaces of a depression keyway and vertical surfaces of a projection key provide mechanical resistance against lateral movement of the cutting insert. This mechanical resistance reduces displacement of the insert with respect to the bit body during brazing and thus a high quality, accurately aligned drill bit assembly is provided by applicants' invention. The depression keyway is designed so as to minimize the effect of the axial load on the insert by avoiding sharp corners which tend to amplify nominal stress and provides an insert of a proper carbide density after pressing. Integral bit body protuberance means adequately separate the insert within the slot and permit braze flow between the insert and slot.

Abstract: A working tool for use with a percussion power tool and including a cushioning elongate stem (3), and a head (4) connected with the stem (3) for joint rotation therewith and for a limited axial displacement relative thereto, with the tool head (4) being adapted, with respect to its resistance associated with its cushioning properties, to characteristics of the percussion piston (5) of the power tool and with the tool stem (3) and the tool head (4) having mutually abutting each other end surfaces (10) which form at least a partially flat contact upon abutting each other.

Abstract: A drill bit is provided for drilling holes in hard, reinforced material, including reinforced concrete. According to one aspect of the invention, wear-resistant inserts are provided in a cross-shaped pattern. The inserts ensure that the entire bottom surface of the drilled hole is engaged during each drill bit revolution. The inserts may be secured in pockets or slots. Fluid entry ports may be located between the inserts for efficient handling of drilling fluid and removal of drilled material, without impairing the structural integrity of the drill bit. According to another aspect of the invention, the drilling surface is separated into two or more stages to increase drilling efficiency, especially through composite material such as reinforced concrete.

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: Oil well drilling apparatus for drilling deep boreholes. The apparatus includes a high frequency, high voltage, AC generator at the surface of the ground which is connected to an electromagnetic hammer drill bit located at the bottom of the borehole. Electric current is conducted along a special drill string to the electromagnetic hammer drill located at the bottom of the hole. The drill string is a co-axial electrically conductive drill pipe which forms spaced annular current flow paths to the downhole electromagnetic hammer drill, while at the same time, drilling fluid flows along an axial flow path to the vibrating bit located at the bottom of the borehole. A special directional drill collar is positioned immediately above the electromagnetic hammer drill for controlling hole deviation.

Abstract: A rotary percussion rock drill bit has a body and a symmetrical cross-like arrangement of crushing and cutting inserts secured on the body. The bit body has a rearward shank portion and a forward boring head portion with a front face. The cylindrical crushing inserts are secured in the forward head portion and have noncutting hemispherical rock crushing ends exposed at the front face of the head portion. The cutting inserts, which can be rectangular or cylindrical in shape, are secured in the forward head portion and have roof-shaped ends exposed at the front face of the head portion. A peak of each roof-shaped end defines a rock cutting edge. The crushing and cutting inserts are arranged on the head portion with their respective hemispherical and roof-shaped ends in a symmetrical cross-like pattern. The bit body also has a longitudinal central axis, and the crushing and cutting inserts are aligned along planes disposed in orthogonal relation to one another and intersecting at the central axis.

Abstract: In a percussive rock bit or similar tool wherein cemented carbide cutting inserts are retained in open radial slots in the head of the tool, an improved method of mechanically retaining the inserts. The inserts are provided with a plurality of elongated radially aligned serrulations along each flank thereof, the thickness of the insert as measured between the crests of opposing serrulations being such as to provide a substantial interference with the slot wall. The inserts may be cold fitted by sliding along the slot, following which body material is peened so as to overlay a small chamfer at the base of the outwardly facing wall of the inserts. The inwardly facing walls of the inserts may be inclined so as to retain the center plug of the rock bit mechanically.

Abstract: A bit for drilling holes in rocks comprising inserts of sintered carbide, the base of which in a plane perpendicular to the edge of its drill point follows a downward convex curve along the symmetry axis of the cross-section of the insert. The insert has the shape of an quadrangle in a section perpendicular to the cross-section of the insert, the side situated nearest to the axis of the bit being inclined at an acute angle .phi., and the side corresponding to the base of the insert being inclined thereto at an angle .epsilon. determined by the relationship 90.degree.>.epsilon..gtoreq.90.degree.-.phi., wherein .phi.<30.degree.. The plane of symmetry of the insert, taken perpendicular to the cross-section of the bit is inclined at an angle .tau. determined by the relationship 90.degree..ltoreq..tau..ltoreq.90.degree.+.gamma., wherein .gamma. is the angle of incidence of the drill point of the bit.

Abstract: Rotary percussive drill bits comprising a body having a longitudinal axis, side face, end face, and cutting inserts, arranged such that during rotary percussive drilling wear tends to take place over a clearance face of the insert thus preserving the leading cutting edge of the insert, wherein the inserts have a substantially flat leading face which projects axially fowardly of the body end face to communicate at the leading cutting edge with a clearance face, with the leading cutting edge extending radially outwardly beyond the side face of the bit body.