Sumitomo Electric Industries, Limited

Sumitomo Electric Hardmetal Corp.

Norihide Kimura

Daisuke Murakami

Junya Okida

Masanobu Ueda

Akihiko Ikegaya

Keiichi Tsuda

Nobuyuki Kitagawa

Nobuhiro Takahashi

Kazuhiko Kashima

Reizo Murakami

Hideto Iyori

Shinya Fujisawa

In order to perform turning operations of the kind that has heretofore been performed by diamond-shaped inserts, an insert which is basically equilateral triangular in shape with multiple alternately usable cutting edges, of which all three corners are usable as cutting edges, without decreasing the positional accuracy of the cutting edge during cutting. At least one recess and a plurality of protrusions are formed on each side of the insert. The recess and protrusions formed on the insert are brought into engagement with a protrusion and recesses formed on a side wall of a seating groove formed in a holder. In this state, the insert is pressed against a bottom seating face and the side wall of the seating groove with a clamp as a means to stably restrain the insert. This prevents shifting of the cutting edge during cutting even if the direction of the cutting force changes.

Edge replacement tip and cutting tool using the same

An indexable insert has a rake face on which a first ridge () and a second ridge () are provided. The first ridge () protrudes from a boss surface () towards a nose, and the second ridge () extends continuously from the first ridge () to a slope () connected to a cutting-edge land () of a linear cutting edge (). The second ridge () has a height lower than that of the first ridge () and is convex-curved towards a bisecting line (CL) of an apex angle of the nose in plan view, thereby achieving both enhanced chip processability and reduction of load received when raking a chip.

Indexable insert

An object is to provide a vibration suppressing cutting tool which is inexpensive and can damp chattering extremely effectively, and which is simple in structure and is applicable to a wide variety of machining diameters and cutting conditions. The shankof the holderis formed with a pocket. In the pocket, a vibration suppressing pieceis received so as to be movable relative to the holderand not protrudable from the pocket. Under kinetic energy from the holder during cutting, the vibration suppressing piecealternately knocks against a pair of opposed inner wall surfacesandof the pocket along its surface, along a plurality of lines or on a plurality of points when the holder vibrates during cutting, thereby damping vibrations of the holder.

Vibration suppressing cutting tool

A holderhas a shank portionprovided with a pockethaving the shape of a nearly rectangular solid. The pocketis placed at a position relatively close to the tip of the tool. In the cross section of the shank, the pockethas a width of 50% to 100% of the shank diameter or width, a height of 20% to 50% of the shank height, and a length of 50% to 250% of the shank diameter or height. A weightis inserted into the pocketsuch that the weight is movable but unable to rush out. The weighthas the shape of a nearly rectangular solid and is made of a material having a specific gravity comparable to or greater than that of the material of the shank portion.

Vibration-suppressing cutting tool

An indexable insert with a chip breaker configured such that chips produced under various cutting conditions from rough cutting to finish cutting can be disposed of in an optimum way. Protrusions are provided in a chip breaker groove to extend from a central land toward the respective corners of the insert. Each protrusion has a breaker wall which is concave and curved such that chips produced always collide against the breaker wall at an angle of 10.degree.-40.degree. so that the chips are curled helically with a helix angle of 10.degree.-40.degree. and broken into small pieces reliably.

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.

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Hyogo, Japan

Norihide Kimura