A rotary tool may include a body, the body may include a cutting edge and a first groove. The first groove may include a first region having a first helix angle, a second region having a second helix angle, a third region having a third helix angle, a fourth region having a fourth helix angle, and a fifth region having a fifth helix angle. The fourth helix angle and the fifth helix angle may each decrease from a side of a first end toward a second end. A decreasing range of a value of the fourth helix angle of the fourth region may be less than a decreasing range of a value of the fifth helix angle of the fifth region. A length of the fourth region may be greater than a length of the fifth region.

A method is specified for producing a rotary tool (2) having a base body (4), which extends in a longitudinal direction (L) and in which at least one flute (6) is ground in by grinding in a first partial flute (12A) with a first helix angle (W1) in a first grinding step and by subsequently grinding in a second partial flute (12B) with a second helix angle (W2) in a second grinding step, the second helix angle differing from the first helix angle (W1) so that a flute (6) that expands in the longitudinal direction (L) is formed, wherein the two partial flutes (12A, 12B) are ground in using the same grinding wheel (11). In this way, a particularly quick production is realized. Furthermore, a corresponding rotary tool (2) is specified.

A tapered drill bit having a proximal end and a distal end includes a shank extending from the distal end at least partially towards the proximal end of the tapered drill bit and a body coupled to the shank. The body includes a tapered portion and the body extends from the shank to the proximal end of the tapered drill bit. The tapered drill bit further includes at least one flute extending from the proximal end along a portion of the body. The tapered drill bit also includes a conduit extending from an inlet aperture at the distal end to an outlet aperture, wherein the outlet aperture is formed through the at least one flute.

A cutting tool is configured to cut and countersink a hole in a workpiece. The cutting tool includes a shank and a fluted body extending along an axis. The body includes a tip, a chamfer in an axially spaced relationship with the tip and a cross hole with a proximal end opening to the chamfer. The body has a cutting section extending between the tip and the chamfer, and a countersinking section extending along the chamfer. At the cutting section, the body includes at least one hole-cutting edge. At the countersinking section, the body includes a scalloped countersink-cutting edge along a junction of the chamfer and the proximal end of the cross hole.

The invention relates to a rotary tool as well as to a carrier and a cutting insert of such a rotary tool. The carrier comprises a seat, which comprises several lateral surfaces, between which the cutting insert can be inserted. The cutting insert comprises, for each of the lateral surfaces, a contact surface which abuts against the respective lateral surface in an inserted state. At least one coolant channel is formed, which comprises a first partial channel and a second partial channel, which adjoins the first partial channel, wherein the first partial channel proceeds within the carrier up to an outlet opening, wherein the second partial channel proceeds within the cutting insert from an inlet opening up to a coolant outlet, wherein the outlet opening and the inlet opening form an interface for transferring coolant from the carrier to the cutting insert. The outlet opening is arranged in one of the lateral surfaces and the inlet opening is arranged in one of the contact surfaces.

A fluted drill comprises, in axial sequence, a body portion, and a cutting portion. The cutting portion comprises two or more cutting edges, with each cutting edge extending from a distal end of the cutting portion, along the cutting portion towards the body portion, to the body portion.

Each cutting edge has a first rake angle at the distal end of the cutting portion, progressively increasing to a third rake angle at a proximal end of the cutting portion. Each cutting edge has a first uncut chip thickness at the distal end of the cutting portion, progressively decreasing to a third uncut chip thickness at the proximal end of the cutting portion.

A blade section has two lands and two flutes in an alternating manner and also has a linear chisel edge. The lands are each provided with: a margin section that is continuous with a cutting blade; a clearance section that is continuous with the margin section and that has a smaller diameter than the margin section; and a pad that is continuous with the clearance section and that has the same width as the width of the margin section.

An instrument comprising a shank and a working portion, the working portion having a tip and a plurality of flutes being defined by at least two lands having a land margin; wherein the working portion has a parabolic cross-section defining opposing convexed surfaces extending between at least two opposing land margins.

A self-locking head-replaceable carbide drill, comprising a cutter head disposed at the upper end of a cutter shank. A cylinder is disposed at the lower part of the cutter head, a vertical cylinder holding slot or cylinder handle holding hole is disposed at the upper end of the cutter bar, at least two cutter head notches are disposed on the drilling body of the cutter head, and each cutter head notch is formed by intersecting a first and a second cutter head contact face. At least two upward protrusions disposed on the wall of the upper end of the cutter bar and have the same number as the cutter head notches. When assembling the cutter head and the cutter shank, the cutter head ridge edges and the inner surfaces of the protrusions are in non-contact fit, interference fit and non-interference fit in sequence.

The drill of the present invention includes: a drill main body; a chip discharge flute extending from a tip flank face of the drill main body toward a rear end side of the drill main body and formed on an outer circumference of a tip part of the drill main body; a margin formed at an opposite side of the chip discharge flute in the drill rotation direction; and a body clearance formed at an opposite side of the margin in the drill rotation direction and having an outer diameter smaller than that of the margin. A surface roughness of the body clearance at least along a circumferential direction is equal to or less than a surface roughness of the margin.