US 2024/0351118 A1Published application

Drill

AssigneeNachi-Fujikoshi Corp.

InventorsYudai YAMADA, Kosuke ARAKI, Junichi NOSHIRO

Life of this patent

Estimating the term…

Loading patent…

Abstract

There is provided a drill including cutting edges wherein each of the cutting edges includes a first cutting edge extending outward in the radial direction from a chisel edge, a second cutting edge having a straight part extending outward in the radial direction from the first cutting edge, a third cutting edge extending outward in the radial direction and extending in a circumferential direction and toward a rear of the drill from the second cutting edge, and a fourth cutting edge extending toward the rear of the drill from the third cutting edge and connected to a leading edge. A first point angle α1 formed by the first cutting edge is set not larger than a second point angle α2 formed by the second cutting edge, and the first point angle α1 formed by the first cutting edge is set within the range of 90° to 140°.

Claims12

Dependent claims

A drill comprising:

cutting edges formed to extend outward in a radial direction of the drill from a central axis of the drill;
flanks formed to extend outward in the radial direction of the drill from the central axis;
and
thinning faces formed closer to the central axis,
wherein each of the cutting edges includes
a first cutting edge adjacent to one of the thinning faces and extending outward in the radial direction of the drill from a chisel edge,
a second cutting edge having a straight part extending outward in the radial direction of the drill from an end of the first cutting edge,
a third cutting edge extending outward in the radial direction of the drill and extending in a circumferential direction of the drill and toward a rear of the drill from an end of the second cutting edge, and
a straight fourth cutting edge extending toward the rear of the drill from an end of the third cutting edge and connected to a leading edge,
a point angle α1 formed by the first cutting edge is not larger than a point angle α2 formed by the second cutting edge, and
the point angle α1 formed by the first cutting edge is within the range of 90° to 140°.

8 more elements

A drill comprising:

cutting edges formed to extend outward in a radial direction of the drill from a central axis of the drill;
flanks formed to extend outward in the radial direction of the drill from the central axis;
and
thinning faces formed closer to the central axis,
wherein each of the cutting edges includes
a first cutting edge adjacent to one of the thinning faces and extending outward in the radial direction of the drill from a chisel edge,
a second cutting edge having a straight part extending outward in the radial direction of the drill from an end of the first cutting edge,
a third cutting edge extending outward in the radial direction of the drill and extending in a circumferential direction of the drill and toward a rear of the drill from an end of the second cutting edge, and
a curved fourth cutting edge extending toward the rear of the drill from an end of the third cutting edge and connected to a leading edge,
a point angle α1 formed by the first cutting edge is not larger than a point angle α2 formed by the second cutting edge, and
the point angle α1 formed by the first cutting edge is within the range of 90° to 140°.

8 more elements

Dependencies are inferred from the claim text.