US 4,059,363 AGranted

Cutting plates with rounded cutting edges and concave frustoconical cutting surfaces

AssigneeUgine Carbone

InventorGerard Romagnolo

Life of this patent

Estimating the term…

Loading patent…

Abstract

A new cutting plate with a chip-breaker on at least one of the working faces, the plate being triangular or quadrilateral, with a preferably zero or positive back clearance and with a cutting angle which may generally be of any size but preferably positive. The plate is characterized in that the back clearance angle .delta. and cutting angle .eta. are obtained from cutting surfaces which are portions of conical surfaces with axes perpendicular to the plane Q.sub..gamma. containing the main cutting points, that the cutting edge comprises at least one arc of a curve, representing the intersection between at least one cone and the plane Q .alpha., and that the cutting surface adjoining a cutting point, comprising two consecutive surface elements joined along an arc of a curve in the plane bisecting the cutting point, causing discontinuity in the lines of level, is such that the cutting angle decreases as the plane No approaches the cutting point.

Claims16

Dependent claims

A cutting plate of polygonal cross-sectional shape and including a chip-breaker on at least one of its working faces, said plate having an upper surface, a lower surface and a plurality of side surfaces defining said polygonal shape, at least one cutting point on a cutting point plane generally parallel to and below said upper surface, at least two cutting surfaces each defined by at least one conical surface with an axis perpendicular to said cutting point plane, said cutting point including a cutting edge at said cutting plane and comprising a surface generated by an arc of a curve adjacent an intersection between two of said side surfaces, two of said cutting surfaces in the region of said cutting point being joined along an arc of a curve bisecting said cutting point in a plane perpendicular to said cutting point plane wherein a discontinuity is provided by the angle of said two cutting surfaces decreasing as each of said conical cutting surfaces approaches said arc of a curve bisecting said cutting point, and the juncture of said side surfaces and said cutting surfaces comprising a cutting edge defined by a plane Q.alpha. connecting two cutting points, which plane Q.alpha. defines a portion of said polygonal shape.

Dependencies are inferred from the claim text.