According to one implementation, a hole finishing tool includes a reaming cutter and a holder. The reaming cutter has a first detaching structure. The first flow path for ejecting cutting oil is formed inside the reaming cutter. The holder has a second detaching structure. The second detaching structure is detached from and attached to the first detaching structure. The second flow path for supplying the cutting oil to the first flow path is formed inside the holder. The holder has a shank. The shank is held by a tool rotating device. The holder has a sliding portion. The sliding portion has no back taper. The sliding portion is inserted into a positioning bush and slid inside the positioning bush. The sliding portion has a concave portion for storing lubrication oil.

A rotary tool according to a non-limiting aspect has a body that has a rod shape extending from a first end to a second end and is rotatable about a central axis. The body has a first cutting edge positioned on the first end, a first flute extending from the first cutting edge toward the second end, a second cutting edge being on a side of the second end and on a side of an outer periphery with respect to the first cutting edge and being positioned away from the first cutting edge, and a second flute, extending from the second cutting edge toward the second end and being positioned along the first flute. The second flute has a projecting portion extending from a side of the first end toward a side of the second end.

The invention relates to a rotary cutting tool (1), such as a drill (2) or a reamer (3), extending longitudinally along an axis (4) and comprising at least one main cutting edge (5) so that when the tool (1) is rotated about the axis (4), the tool (1) advances axially to perform a cutting operation on a material.

According to the invention, the tool (1) comprises means for braking (7) the axial advance of the tool (1) during the cutting operation.

The invention relates to a rotary cutting tool (1), such as a drill (2) or a reamer (3), extending longitudinally along an axis (4) and comprising at least one main cutting edge (5) so that when the tool (1) is rotated about the axis (4), the tool (1) advances axially to perform a cutting operation on a material.

According to the invention, the tool (1) comprises means for braking (7) the axial advance of the tool (1) during the cutting operation.

A cutting tool, such as a reamer, includes a rear machine connection member, a center tube, a front cutting ring, and a rear cutting ring. The front cutting ring includes a sleeve member and one or more cutting head assemblies. Each cutting head assembly includes at least one support arm extending radially outwardly from a rotational axis, RA, of the cutting tool, and a cutting head supported by the at least one support arm. The at least one support arm of the cutting head assembly defines a fluid dynamic structure for directing fluid flow in a desired direction to facilitate chip evacuation during a cutting operation. The fluid dynamic structure can be an airfoil, a turbine blade, or similar structure that produces a directed fluid flow.

A reamer incudes a core and a plurality of outer-circumference cutting edges provided on an outer circumference of the core and made of a hard tool material. The core extends from a front end to a rear end. The core is provided with a plurality of flutes from the front end to the rear end. A center-of-gravity adjustment portion, which adjusts a distance from a center of rotation to a center of gravity, is provided at least partially from terminal ends of the plurality of flutes on a rear end side to the rear end of the core. The center-of-gravity adjustment portion causes the deviation of the center of gravity from the center of rotation to be smaller than when no center-of-gravity adjustment portion is provided.

A reamer incudes a core and a plurality of outer-circumference cutting edges provided on an outer circumference of the core and made of a hard tool material. The core extends from a front end to a rear end. The core is provided with a plurality of flutes from the front end to the rear end. A center-of-gravity adjustment portion, which adjusts a distance from a center of rotation to a center of gravity, is provided at least partially from terminal ends of the plurality of flutes on a rear end side to the rear end of the core. The center-of-gravity adjustment portion causes the deviation of the center of gravity from the center of rotation to be smaller than when no center-of-gravity adjustment portion is provided.

A rotary tool according to a non-limiting aspect includes a body having a rotation axis and extending from a first end to a second end. The body including: a first part including the first end; a second part located closer to a second end than the first part and having a larger outside diameter than the first part; a cutting edge located at a side of the first end; a ridge portion located in the first part and the second part, connected to the cutting edge and helically extending from the cutting edge toward the second end; and a flute located along the ridge portion. The flute includes: a first flute located at the first part and having a first helix angle; and a second flute located at the second part and having a second helix angle. The second helix angle is smaller than the first helix angle.

A reamer includes a shank portion extending from a rear end and a cutting portion extending from the shank portion to a front end. The cutting portion includes a plurality of cutting teeth separated by gashes. Each cutting tooth having a cutting edge extending in a longitudinal direction from the front end to proximate the shank portion. The cutting portion includes a margin trailing each cutting edge and extends along each cutting edge to proximate the shank portion. Each cutting tooth also has a primary relief formed between the cutting edge and the front end and a secondary relief extending longitudinally between the margin of one cutting tooth to the cutting edge of an adjacent cutting tooth. A width, W, of each cutting tooth increases in a radially outward direction with respect to the central, longitudinal axis when viewed from the front end of the reamer.

Provided is a coated cutting tool that has a nitride hard coating that contains Ti at 70 at % to 95 at % and Si at 5 at % to 30 at % with respect to the total amount of metallic elements, and Ar at 0.05 at % to 0.20 at % with respect to the total amount of metallic and non-metallic elements, has a NaCl-type crystalline structure, exhibits maximum diffraction peak intensity in the (200) plane, and has an average grain size of 5 nm to 30 nm. When 100 at % is defined as the total of content rates of the metallic elements, nitrogen, oxygen, and carbon in a composition at intervals of 20 nm from a depth of 20 nm to 200 nm from a surface of the hard coating, the content rate of nitrogen is 50.0 at % or more.