Drills and methods of removing material using drills are disclosed. Drills may include a plurality of lands that extend to a cutting edge, where adjacent lands are separated by flutes comprising a base contour arranged in a generally helical configuration along a centerline axis of a drill body. The drill also includes a plurality of contoured drill points each having a linear portion that extends towards an outer diameter of the drill body, and an arcuate portion that extends from the linear portion and towards a chisel of the drill body. The drill further includes a plurality of gash contours positioned within the plurality of flutes. The gash contours extend from the chisel of the drill body, and the gash contours are oblique to the base contours of the flutes.

A drilling tool is configured to perform drilling and/or percussive work on materials such as stone, concrete and/or reinforced concrete. The drilling tool has a fastening region and a working region. The working region has a working body and at least one cutting element projecting axially and/or radially in relation to the working body. The at least one cutting element has at least one first cutting edge and at least one second cutting edge. The at least one second cutting edge is configured to serve as a replacement cutting edge and/or as an auxiliary cutting edge, and the at least one second cutting edge is set back, at least partly, in relation to the at least one first cutting edge of the drilling tool, axially along a longitudinal axis of the drilling tool, in a direction towards the fastening region.

A drill structure comprises a shank part and a bit part. A web is formed on the front end of the bit part. Two sides of the web are tilted backward to form two cutting faces. At least one flute (chip-discharge groove) is formed on the surface of the bit part. Each cutting face includes a primary cutting face and a secondary cutting face. The thickness of the prismatic web edge of at least one primary cutting face is smaller than the outer-side width of the primary cutting face. An auxiliary cutting face is extended to the wall of the flute from the cutting edge of the primary cutting face and a portion of a blade back of the secondary cutting face of another cutting face. The present invention decreases the drilling resistance during drilling a hole and increases the service life of the drill bit.

The invention relates to a carbide insert (2) for a rock drill (1), which is configured as a non-percussively operating twist drill with a cylindrical drill body (11) and a working end (13) having the carbide insert (2), the carbide insert (2) having two cutting lips (22) which are radially opposite one another relative to an axis of drill rotation (d) and are arranged at an angle to one another to form a centering tip (21) and with each of which a peripheral conveyor spiral (14) may be associated. To be able to introduce a drilled hole more quickly, easily and simply and with less risk of damage into a workpiece of rock, rock-like material, hard plastics, glass or the like, it is proposed that the cutting lips (22) be configured asymmetrically to one another, wherein at least one of the cutting lips (22) defines over its radial profile, in a central region spaced from its radial ends, a tip (23) projecting in the drilling direction (b).

A drill bit includes a body having a first end, a second end opposite the first end, and an axis of rotation extending centrally through the body. The drill bit includes a cutting head with a cutting tip on the axis of rotation and a cutting portion. The cutting portion includes first tip surfaces on opposite sides of the axis of rotation and second tip surfaces on opposite sides of the axis of rotation. Each first tip surface extends radially outward from the cutting tip to a corresponding second tip surface. Each second tip surface extends from a corresponding first tip surface to an outer periphery of the body. The first tip surfaces define a first tip angle measured through the axis of rotation that is oblique. The second tip surfaces define a second tip angle measured through the axis of rotation that is smaller than the first tip angle.

The invention relates to a rotary tool, in particular a drill (2), which extends along a longitudinal axis (4), having an end face (6); a center (12); at least two main cutting edges (8), each of which extends from the center (12) outwards towards a cutting corner (10); a flute (20) associated with each main cutting edge (8), a flank on the end face (18), associated with each main cutting edge (8); a rake angle () between the respective main cutting edge (8) and the flute (20); a ground face (26) which forms a point thinning (30) in the area of the center (12), extends into a radially outer area and defines the rake angle () in the area of the main cutting edge (8). The rotary tool is characterized in that the rake angle () formed by the ground face (26) is constant along the main cutting edge (8), and the flank (18) of the other main cutting edge (8) is formed by the ground face (26). An advantageous, excellent cutting behavior is thereby achieved along the main cutting edge (8). The invention further relates to a method for manufacturing the rotary tool, which is then especially simple to produce.

A rotary cutting tool with an elongate body disposed about a longitudinal axis, the elongate body including a helical flute and a polycrystalline-diamond cutting tip. The cutting tip comprises an inner portion having an inner point angle and an outer portion having an outer point angle different from the inner point angle.

Provided are a hole formation method enabling the formation of a high-quality hole even when a workpiece material is a difficult-to-machining metal material or a fiber-reinforced composite material and a drill bit used in the method. A drill bit includes at least one cutting edge and a leading flank adjacent to the cutting edge, and the leading flank is set to have a surface roughness Ra of 2.0 m or more and 3.0 m or less. A hole formation method includes a hole formation step of machining a portion to be processed of a workpiece material by means of drilling to form a hole while a lubricant material for assisting machining process is in contact with a drill bit and/or the portion to be processed, and in the hole formation step, the drill bit is used.

Provided is a drill having a flat-shaped drill tip and excellent in cutting edge strength and chip removability. The drill includes: a cutting edge extending in a direction at an angle of not less than 85 and not more than 90 with respect to a drill axis (line O-O); a flank face contiguous to the cutting edge and having a clearance angle of not less than 5 and not more than 10 with respect to the drill axis (line O-O); and a rake face located opposite to the flank face across the cutting edge, the cutting edge includes a recess receding in a direction parallel to the drill axis (line O-O), and the rake face includes a front clearance formed at a side of an outer periphery of the drill.

A drill according to an embodiment of the present invention has a pair of main cutting edges positioned at a front end of a drill body, a pair of first chisel edges each extending from the pair of main cutting edges toward a rotation axis, and a second chisel edge positioned between the pair of first chisel edges and intersecting with the rotation axis of the drill body. When viewing a locus of rotation of the pair of first chisel edges and a locus of rotation of the second chisel edge in a cross section taken so as to include the rotation axis, the respective locus of rotation of the pair of first chisel edges have a rectilinear shape, and respective imaginary straight lines obtained by extending the locus of rotation of the pair of first chisel edges toward the rotation axis are positioned further to a rear end side of the drill body than the locus of rotation of the second chisel edge.