Sumitomo Electric Industries, Limited

Nobuhiro Takahashi

Kazuo Noguchi

Tsuyoshi Asai

Masafumi Hideshima

Norihide Kimura

Shinya Fujisawa

Shuichi Hori

A throw-away insert for low-depth-of-cut finish cutting can be used over a wide range of feed rates. A breaker groove is provided between the center land and each cutting edge. An arcuate small protrusion is formed on the bisector of each nose portion. A narrow groove is formed in the small protrusion. Thin chips, which are produced while the feed rate is low, are curled and broken by the groove formed in the protrusion. Thick chips, which are produced while the feed rate is high, are guided along the grooves and collide with an edge of a side wall of the center land. Thus, thick chips are also smoothly curled and broken by the edge.

Throw away insert

A throw-away insert having straight cutting edges defined adjacent the periphery thereof, arcuately curved corner portions extending between adjacent ones of the cutting edges, and a rake face having a center land. In the rake face, chip breaker grooves are formed near the corner portions. Each breaker groove adjoins the center land along a line inclined with respect to one of the adjacent cutting edges and is inclined with respect to the direction of thickness of the insert. An ellipsoidal recess is formed in the bottom surface of each breaker groove across the boundary between the center land and the breaker groove. The ellipsoidal recesses have a major axis extending parallel to the borderline between the center land and the breaker groove.

Tip for a cutting tool

A throw away cutting tool comprising a holder formed with a wedge groove and a throw away insert having a cutting edge at one end thereof and a wedge portion at the other end, the wedge portion being adapted to be clamped in the wedge groove by elasticity of the material of the holder. The holder is at least partly made of cemented carbide for higher rigidity and cutting stability. Also, the radius of curvature at the deep end of the wedge groove is optimized for crack resistance. Further, the angle of the V-ridge on the holder is interrelated to the angle of the V-groove in the insert for more holding stability and crack resistance.

Throw away cutting tool

A polygonal throw-away insert defining a cutting edge at the periphery thereof, a center land and a breaker groove formed therein between the cutting edge and the center land. Pairs of slopes protrude upwardly in the breaker groove, near each corner portion of the insert, at an oblique angle of 5-20 degrees and in symmetrical relation with each other with respect to the bisectors of the corner portion so as to define a ridge therebetween. Breaker protrusions extend from the center land toward the corner portions and have tapered ends. Breaker walls extend obliquely upwardly from rear ends of the pairs of slopes to the front ends of the breaker protrusions, respectively. And ellipsoidal grooves are formed in the breaker grooves so as to be contiguous with the breaker walls.

A throw-away thread cutting insert having a cutting tip at a corner part thereof corresponding to a shape of a thread groove, a lead groove formed in an upper surface of the insert and disposed adjacent to and inwardly of said cutting tip, and a curl recess formed in an upper wall of the insert in continuous relation to one side wall of the insert and disposed inwardly of said lead groove.

Thread cutting throw-away tip

An indexable cutting insert of a polygonal shape including a plurality of nose portions formed at vertexes of the polygonal shape, respectively, a cutting edge formed between neighboring ones of the nose portions, a land portion formed inside the cutting edge and a dimple formed, in the vicinity of each of the nose portions and the land portion, inside each of the nose portions, with the cutting edge being inclined upwardly in a direction away from each of the nose portions.

Indexable cutting insert

A throw away cutting tool comprising a holder formed with a wedge groove and a throw away insert having a cutting edge at one end thereof and a wedge portion at the outer end, the wedge portion being adapted to be clamped in the wedge groove by elasticity of the material of the holder. The holder is at least partly made of cemented carbide for higher rigidity and cutting stability. Also, the radius of curvature at the deep end of the wedge groove is optimized for crack resistance. Further, the angle of the V-ridge on the holder is interrelated to the angle of the V-groove in the insert for more holding stability and crack resistance.

Growing community of inventors

Itami, Japan

Nobuhiro Takahashi