A drill bit for drilling into bone, including at least a first, second and third longitudinally extending substantially straight flute blades, wherein the drill bit has an extrapolated outer profile established by rotation of the first, second and third flute blades 360 degrees about a longitudinal axis thereof, the extrapolated outer profile includes a first surface having tangents more perpendicular than parallel to the longitudinal axis, and the extrapolated outer profile includes a second surface having tangents more parallel than perpendicular to the longitudinal axis.

A drill reamer (20) comprises an elongate body (21) disposed about a longitudinal axis. The elongate body comprises flutes (22a-22d) having separate hard cutting sections (27a, 28a, 28a, 28b, 28b) and a soft cutting section (24a, 24b). The soft cutting section is formed of a material such as carbide having a hardness that is less than that of the hard cutting sections, which may be formed of polycrystalline diamond. At least one first hard cutting section (27a) is axially displaced relative to at least one second hard cutting section (28a, 28a). The reamer has a tip cutting edge (23a, 23c) and tapered cutting edge portions (24a-24d) disposed at an acute angle relative to the longitudinal axis.

A drill bit for a drill includes at least one flute having a rake face including a flute edge and at least one cutting edge having a profile that extends along at least a portion of a length of the cutting edge, the rake face extending from the cutting edge. A chip breaker formed in the rake face, the chip breaker being a continuous groove located adjacent the cutting edge, the groove having a starting end and an exit end opening into the flute edge, the starting end having a depth that is less than a depth of the exit end of the groove, wherein a shape of the groove at the starting end is different from a shape of the groove at the exit end.

In order to ensure good guidance of a drilling tool at the start of a drilling operation and at the same time ensure a reliable evacuation of a center chip, in the drill bit, in a tool flank adjoining a respective main cutting edge, an additional point thinning is recessed in the region of a transverse cutting edge, which additional point thinning, extending in a principal direction from the tool flank, merges, with a convex course, into a chip flute. As a result of the convex design, an as far as possible homogeneous, edge-free transition into the chip flute is obtained. Since the point thinning is additionally made, the tool flank, even in the rear end facing away from the cutting edge, remains at a front axial position, so that a second land is effective for a reliable guidance of the bore already at an axially front position.

A laser beam is transmitted through a drill bit comprising diamond or other suitable light-transmitting material having sufficient hardness. The laser beam exits a tip of the drill bit, thereby heating and softening the material being drilled at and/or near the interface of the drill with the material being drilled. The process may be utilized to drill hard and brittle materials such as ceramics and semiconductors, composites and ceramic matrix composites. The process may cause high pressure phase transformation, resulting in a more ductile and plastic material near the drill point/tip. The process provides more rapid drilling, improved surface quality in drilled holes, and less tool wear.

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.

The present disclosure relates to cutting tools and cutting inserts in general, and more particularly to the specific shapes of cutting edges on cutting tools and cutting inserts. In an embodiment, a cutting tool with a cutting edge formed as a sinusoidal curve is provided. In an embodiment, a rotary drill bit including a cutting insert comprising a sinusoidal curve is provided.

A drill bit for drilling into bone, including at least a first, second and third longitudinally extending substantially straight flute blades, wherein the drill bit has an extrapolated outer profile established by rotation of the first, second and third flute blades 360 degrees about a longitudinal axis thereof, the extrapolated outer profile includes a first surface having tangents more perpendicular than parallel to the longitudinal axis, and the extrapolated outer profile includes a second surface having tangents more parallel than perpendicular to the longitudinal axis.

A rotary tool, in particular drilling tool, extends along a longitudinal axis and has an end surface; a brad point; and at least one major cutting edge extending outward up to an edge corner. A first free surface segment adjoins the major cutting edge, and a second free surface segment in turn adjoins said first free surface segment. To keep the stress, in particular the wear, low in the region of the end surface, the first free surface segment has a lower average abrasiveness than the second free surface segment.

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.