Cutting tool with replaceable cutting insert

An indexable double-sided cutting insert having a substantially prismatic shape, said insert for use in a cutting tool assembly comprising a tool holder formed with a cutting insert retaining pocket having an insert supporting surface and an insert supporting projection formed thereon, said insert comprising:

• an upper and a lower insert surface having respective upper and lower rake surfaces and upper and lower bearing surfaces;
• side relief surfaces between said upper and lower insert surfaces;
• upper and lower cutting edges defined respectively between said side relief surfaces and respective said upper and lower rake surfaces;
• insert corners defined between pairs of adjacent side relief surfaces and upper and lower cutting edges adjacent to said pairs, said insert corners being indexable into an operative position presenting thereby an adjacent pair of operative upper cutting edges and an adjacent pair of inoperative lower cutting edges;
• chip forming grooves respectively formed in said upper and lower rake surfaces adjacent said cutting edges;
• and insert support recesses formed respectively on said upper and lower rake surfaces, and being respectively disposed adjacent to said insert corners and adapted to receive contactingly said insert supporting projection, each recess being located inwardly of an adjacent deflection wall of said chip forming groove so as to ensure that generated chips are deflected from the recess.

A cutting tool assembly comprising:

• (a) an indexable double-sided cutting insert having a substantially prismatic shape, said insert comprising an upper and a lower insert surface having respective upper and lower rake surfaces and respective upper and lower beating surfaces;
• side relief surfaces between said upper and lower insert surfaces;
• upper and lower cutting edges defined respectively between said side relief surfaces and respective said upper and lower rake surfaces;
• insert corners defined between pairs of adjacent side relief surfaces and said upper and lower cutting edges adjacent to said pairs, said insert corners being indexable into an operative position presenting thereby an adjacent pair of operative upper cutting edges and an adjacent pair of inoperative lower cutting edges;
• chip forming grooves respectively formed in said upper and lower rake surfaces adjacent said cutting edges;
• and insert support recesses formed respectively on said upper and lower rake surfaces and being relatively disposed adjacent to said insert corners, each insert support recess being located inwardly of an adjacent deflection wall of said chip forming groove so as to ensure that generated chips are deflected from the insert support recess;
• (b) a tool holder formed with a cutting insert retaining pocket having an insert supporting surface, and an insert supporting projection formed on said insert supporting surface, said insert supporting projection adapted to fit contactingly into any one of said insert support recesses, and
• (c) clamping means for retaining said cutting insert in said cutting insert retaining pocket with said cutting insert being firmly clamped at a first side portion thereof remote from said pair of operative cutting edges against said pocket side wall, said insert supporting surface in clamping contact with the adjacent insert bearing surface, and with said insert supporting projection locally supporting the cutting insert at its operative insert corner, and said adjacent pair of inoperative lower cutting edges being spaced from said insert supporting surface.

A cutting tool assembly comprising:

• (a) a tool holder formed with a cutting insert retaining pocket defined by a pocket base wall and a pocket side wall;
• (b) an indexable double-sided cutting insert having a substantially prismatic shape and comprising an upper and a lower insert surface having respective upper and lower rake surfaces and respective upper and lower bearing regions;
• side relief surfaces between said upper and lower insert surfaces;
• upper and lower cutting edges defined respectively between said side relief surfaces and upper and lower rake surfaces;
• insert corners defined between pairs of adjacent side relief surfaces and upper and lower cutting edges adjacent to said pairs, said insert corners being indexable into an operative position presenting thereby an adjacent pair of operative upper cutting edges and an adjacent pair of inoperative lower cutting edges;
• chip forming grooves respectively formed in said upper and lower rake surfaces adjacent said cutting edges;
• and insert support recesses formed respectively on said upper and lower rake surfaces, and being respectively disposed adjacent to said insert corners, each insert support recess being located inwardly of an adjacent deflection wall of said chip forming groove so as to ensure that generated chips are deflected from the insert support recess;
• (c) a shim substantially corresponding in shape to said cutting insert, said shim formed with an upper shim surface and shim corners, said upper shim surface being provided with an insert supporting projection adjacent to one of said shim corners and adapted to fit contactingly into any of said insert support recesses;
• and
• (d) clamping means for retaining said cutting insert and said shim in said cutting insert retaining pocket so that the lower surface of the insert is firmly supported, at the operative cutting corner, by said insert supporting projection and, on either side thereof, by adjacent bearing regions which bear on said upper surface of the shim, said adjacent pair of inoperative lower cutting edges being spaced from said upper surface of the shim.

A cutting tool assembly comprising:

• (a) an indexable double-sided cutting insert having a substantially prismatic shape, said insert comprising an upper and a lower insert surface having respective upper and lower rake surfaces and respective upper and lower bearing surfaces;
• side relief surfaces between said upper and lower insert surfaces;
• upper and lower cutting edges defined respectively between said side relief surfaces and respective said upper and lower rake surfaces;
• insert corners defined between pairs of adjacent side relief surfaces and said upper and lower cutting edges adjacent to said pairs, said insert corners being indexable into an operative position presenting thereby an adjacent pair of operative upper cutting edges and an adjacent pair of inoperative lower cutting edges;
• chip forming grooves respectively formed in said upper and lower rake surfaces adjacent said cutting edges;
• and insert support recesses formed respectively on said upper and lower rake surfaces and being relatively disposed adjacent to said insert corners, each insert support recess being located inwardly of an adjacent deflection wall of said chip forming groove so as to ensure that generated chips are deflected from the insert support recess;
• (b) a tool holder formed with a cutting insert retaining pocket having an insert supporting surface, and an insert supporting projection formed on said insert supporting surface, said insert supporting projection adapted to fit contactingly into any one of said insert support recess;
• and
• (c) clamping means for retaining said cutting insert in said cutting insert retaining pocket so that the lower surface of the insert is firmly supported, at the operative corner of the cutting insert, by said insert supporting projection and, on either side thereof, by adjacent regions of the bearing surface which bear on said insert supporting surface, said adjacent pair of inoperative lower cutting edges being spaced from said upper surface of the insert supporting surface.