A drill includes a drill body rotatable about a drill axis, and a cutting portion. The cutting portion includes a first grinding face having first and second chisel edges defining an angle therebetween, and a second grinding face having third and fourth chisel edges defining an angle therebetween, the second grinding face being point-symmetrical with the first grinding face. A first relief face associated with a first cutting edge extends from the first and fourth chisel edges and a second relief face associated with a second cutting edge extends from the second and third chisel edges. A first intersection line is formed where the first and second relief faces meet; a second intersection line is formed where the third and fourth relief faces meet. The first and second intersection lines are spaced apart from an imaginary center line passing through the rotational axis and the first and third relief faces.

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.

This HEMS (200) is provided with a control unit (230) that, if an operation directive does not go through a server (600) provided externally to a customer's home (10), identifies said operation directive as having come from within the customer's home, and if the operation directive does go through the server (600) provided externally to the customer's home (10), identifies the operation directive as having come from outside the customer's home.

A drilling tool includes at least two chip flutes and a chisel edge with a thinned region. The thinned region merges continuously into the chip flutes in such a way that the thinned region forms the end of the respective chip flute in the region of the chisel edge.

A drilling tool includes at least two chip flutes and a chisel edge with a thinned region. The thinned region merges continuously into the chip flutes in such a way that the thinned region forms the end of the respective chip flute in the region of the chisel edge.

A drill has a thinning rake face formed in the front end. An intersection ridgeline between the thinning rake face and the tip flank face is the thinning edge. On the opposite side of the rotation direction, the first and second thinning wall surfaces (6b, 6c) and are formed. Viewed from the front, an intersection angle between the thinning edge (4a) and the first thinning ridgeline is larger than 95. The second thinning ridgeline (L2) is bent to the opposite side of the rotation direction. The thinning edge and the first thinning ridgeline are connected via a concave curve line. The first and second thinning wall surfaces are connected via a concave surface, and a curvature radius of the concave curve line is smaller than a curvature radius of the concave surface.

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.

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 includes a cutting edge. The cutting edge has a point angle which is continuously decreased from a center-position point angle A (herein, 0<A<180) at a center position to a maximum-diameter-position point angle of 0 at a maximum diameter position. The cutting edge has a relief angle which is continuously decreased from the center position to the maximum diameter position. The cutting edge of the drill has a relief angle at the maximum diameter position. Hence, the cutting edge also serves as a cutting edge for reaming. The ridgeline and relief face of the cutting edge have no corner, thereby providing good wear resistance.

A tip for twist drill, comprising a super-hard structure joined to a substrate at an interface boundary coterminous with an end of the substrate, the super-hard structure comprising sintered polycrystalline material comprising super-hard grains, the super-hard structure defining a super-hard end surface opposite the interface boundary and a plurality of cutting edges configured for boring into a body in use; the super-hard end surface including a center point or chisel edge, and comprising a plurality of surface regions configured such that respective planes tangential to each of the surface regions are disposed at substantially different angles from the axis of rotation of the tip in use. Precursor constructions for use in manufacturing the tips as well as methods for making the precursor constructions and the tips are disclosed.