Indexable cutting insert and holder therefor

Claim 2

An insert adapted to be supported on a flat platform on a cutter body and crowded edgewise against walls upstanding from a corner of such platform, said insert comprising a flat and generally rectangular block of cutting material having a center hole conically countersunk at opposite ends to receive a screw for securing the block to said platform and crowding the block edgewise into said corner and having parallel surfaces on opposite sides and faces along opposite side edges constituting the cutting faces of four main cutting edges defined by the intersections of said side surfaces and side edges, each end of said block having clearance faces extending along such end and each defining at opposite ends the finish cutting edge for two of said main cutting edges along the respective side edges of said block, said clearance faces sloping in opposite directions across the block end from said finish cutting edges and being separated from each other by a surface extending across the block and adapted for abutment with one of said corner walls to locate the block endwise relative to said platform.

Claim 3

A cutting insert as defined in claim 1 in which Said clearance faces at the ends of said block are of generally trapezoidal shape.

Claim 4

A cutting insert as defined in claim 2 in which said abutment surface at each end of said insert extends diagonally across the end.

Claim 5

A cutting insert as defined in claim 1 in which said abutment surfaces on said block ends are disposed in parallel planes normal to said sides of said block.

Claim 6

A cutting insert as defined in claim 2 in which said end abutments are flat with generally parallel side edges.

Claim 7

A cutting insert as defined in claim 1 in which said abutment surfaces at opposite ends of said block are disposed in parallel planes and extend diagonally across the block ends in opposite directions so as to lie in longitudinal planes of said block which cross each other.

Claim 8

A cutting insert as defined in claim 1 in which said side edges of said block parallel each other, are perpendicular to said block sides, and form main cutting faces whose clearance faces are formed by said block sides.

Claim 9

A cutting insert as defined in claim 1 including additional abutment surfaces disposed in parallel planes perpendicular to said block sides and extending across and longitudinally of said side edges of said block.

Claim 10

A cutting insert as defined in claim 2 in which the cutting faces of said main cutting edges are disposed at acute included angles relative to the adjacent one of said side faces.

Claim 11

A cutting insert as defined in claim 1 including flats disposed in parallel planes perpendicular to said block sides, the areas of said block edges on opposite sides of said flats being disposed below the planes of said flats and constituting the cutting faces of said main cutting edges whereby the width of said block between said flats remains fixed after successive sharpenings of said main cutting edges by grinding away the cutting faces thereof formed by said edge faces of said block.

Claim 12

A cutter comprising a body having a pocket defined by a platform and side walls upstanding therefrom and defining a corner of the pocket, an insert as defined in claim 1 resting on said platform and crowded into said corner by a screw extending through the center hole of said insert, one of said end abutment surfaces of the insert engaging one of said corner walls and the adjacent side edge of the insert engaging the other corner wall.

Claim 13

A cutter as defined in claim 11 including a groove extending along said other corner wall in the plane of said platform and opposite the main cutting edge so as to avoid engagement of such edge with said other corner wall.

Claim 14

A cutting insert adapted to be supported on a flat platform on a cutter body and crowded edgewise against walls upstanding from a corner of such platform, said insert comprising a flat and generally rectangular block of cutting material having a hole adapted to receive a fastener for securing the block to said platform and crowding the block edgewise into said corner, said block having parallel surfaces (16, 17) on opposite sides and also having faces (23a to 26a) along opposite side edges (18, 19) constituting the cutting faces of four main cutting edges (23 to 26) defined by the intersections of said parallel surfaces and said side edges, each end of said block having clearance faces (21, 22) extending along such end and each defining at one end the finish cutting edge (29, 32) for one of said main cutting edges, said clearance faces sloping in opposite directions across the block end from said finish cutting edges and being separated from each other by a surface (27) extending across the block and adapted for abutment with one of said corner walls to locate the block endwise relative to said platform.

Claim 15

A cutting insert adapted to be supported on a flat platform on a cutter body and crowded edgewise against walls upstanding from a corner of such platform, said insert comprising a flat and generally rectangular block of cutting material having a hole adapted to receive a fastener for securing the block to said platform and crowding the block edgewise into said corner, said block having parallel surfaces (16, 17) on opposite sides and also having faces (23a to 26a) along opposite side edges (18, 19) constituting the cutting faces of four main cutting edges (23 to 26) defined by the intersections of said parallel surfaces and said side edges, each end of said block having clearance faces (21, 22) extending along such end and each defining at one end the finish cutting edge (29, 32) for one of said main cutting edges, said clearance faces sloping in opposite directions across the block end from said finish cutting edges and being separated from each other by a surface (27) extending across the block and adapted for abutment with one of said corner walls to locate the block endwise relative to said platform.