Mitsubishi Hitachi Tool Engineering, Ltd.

Moldino Tool Engineering, Ltd.

Hitachi Tool Engineering, Ltd.

Yasuhiro Kiuchi

Yoshiyuki Kobayashi

Kenji Nagafuchi

Fumihiko Inagaki

Takao Nakamigawa

Yuuki Hayashi

Yoshimitsu Nagashima

A cutting insert includes a rake face, a seating face facing an opposite side to the rake face and seated on an insert mounting seat, and a flank face extending around the rake face and the seating face, in which two cutting edges each having an arcuate cutting edge portion extending in an arc shape and a linear cutting edge portion which is in contact with the arcuate cutting edge portion are formed on an intersecting ridgeline portion between the rake face and the flank face, a groove portion having a wall surface coming into contact with a projection portion protruding from a bottom surface of the insert mounting seat is formed on the seating face, and the groove portion has a narrow width portion in which a groove width decreases from one end side toward the other end side in a direction in which the groove portion extends.

Cutting insert and indexable ball end mill

Cutting insert

This cutting insert has: as cutting edges, arcuate cutting edges that are of an arc shape protruding toward an outer circumference side of a distal end. A chisel part is formed at an intersecting ridge line part between the flank faces of the pair of arcuate cutting edges. A round honing is formed on the cutting edge tip of the arcuate cutting edge at least in a range where a radial angle is 30&#xb0; or less. A curvature radius of the round honing in a cross section perpendicular to the edge length direction of the arcuate cutting edge is 20 to 40 &#x3bc;m. A chisel angle formed between the distal end part of the arcuate cutting edge and a chisel edge of the chisel part is 150&#xb0; to 170&#xb0; as seen in an insert front view.

Cutting insert and cutting edge-interchangeable rotary cutting tool

In an indexable rotary cutting tool of the present invention, a cutting edge portion of an insert includes a peripheral cutting edge, a bottom cutting edge, a cutting edge of a corner R, and a chamfered surface, a radial rake angle (&#x3b4;) of the cutting edge of the corner R has a negative value in an entire edge length region of the cutting edge of the corner R, and the radial rake angle (&#x3b4;) becomes a minimum value at an intermediate portion located between a pair of boundary points (P, Q) in the cutting edge of the corner R.

Indexable rotary cutting tool and insert

An indexable rotary cutting tool and insert is capable of performing a high-accuracy cutting process with high efficiency. A twist angle of an outer peripheral cutting edge of the tool has a positive value, an axial rake angle of the cutting edge of a corner R of the tool at a boundary point between the cutting edge of the corner R and the outer peripheral cutting edge has a positive value, the axial rake angle of the cutting edge of the corner R at a reference point has a negative value, and the radial rake angle at least between the boundary point and the reference point in an entire edge length region of the cutting edge of the corner R has a negative value. The radial rake angle at the reference point is smaller than the radial rake angle at the boundary point.

Cutting insert for a rotary cutting machine tool

A ball-end mill includes arcuate cutting edges each extending from a tip end to a peripherally outermost point along a S shape curve when viewed from the front side, spirally-shaped, peripheral cutting edges each smoothly connected to each arcuate cutting edge, and a convex rake face of each arcuate cutting edge protruding forward in a rotation direction. Each arcuate cutting edge has a radial rake angle satisfying &#x3b2;&#x3c;&#x3b1;&#x2266;&#x3b3;, where &#x3b1; is a radial rake angle at a radial angle of 5&#xb0;, &#x3b2; is a radial rake angle at a radial angle of 90&#xb0;, and &#x3b3; is a radial rake angle at a rotationally most projecting point of the arcuate cutting edge. The radial rake angle has the maximum value at a radial angle in a range of 12-40&#xb0; and continuously decreases in a range from the rotationally most projecting point to the peripherally outermost point.

Growing community of inventors

Narita, Japan

Yasuhiro Kiuchi