Cutting insert with chip control
AssigneeGTE Valenite Corporation
InventorDaniel R. Stashko
Life of this patent
Estimating the term…
Abstract
A cutting tool for improved material removal efficiency at relatively high feed rates is disclosed. In a preferred form of an indexable polygonal cutting insert, an edge land and chip contacting ramp surfaces in at least a top face of the insert are advantageously arranged for reduced cutting forces and friction, ample cutting edge strength and inducement of free chip flow. In order to overcome deleterious chip convergence and resultant high pressures in the vicinity of the nose radius of the cutting corner of the insert, a recessed control surface is positioned in each corner portion of the polygonal insert.
Claims14
In a tool for cutting chip forming materials having a cutting corner defined by the intersection of a chip-breaker surface and two flank surfaces and a cutting edge extending from the cutting corner along a boundary of one of the flank surfaces, the improvement comprising:
- a land surfaces extending inwardly from the cutting corner and the cutting edge;
- a first ramp control surface extending continuously along the cutting edge and the cutting corner from an inner boundary of the land surface downwardly at a first angle to the plane of the chipbreaker surface;
- a corner control surface lying adjacent the first ramp control surface so as to partially interrupt the first ramp control surface only in the cutting corner and extending inwardly from an intersection with the first ramp control surface only in the cutting corner;
- a [second] third ramp control surface lying adjacent the corner control surface only in the cutting corner extending from an intersection with the corner control surface downwardly at a second angle to the plane;
- and
- a [third] second ramp control surface extending parallel to the cutting edge and adjacent the first ramp control surface except in the cutting corner wherein an intersection of the first and [third] second ramp control surfaces is interrupted by the [second] third ramp control surface the third ramp control surface extending downwardly at a third angle to the plane, the corner control surface and the [second] third ramp control surface thereby narrowing the width of the first ramp control surface only at the cutting corner.
A cutting insert comprising a polygonal body having opposed top and bottom faces lying in substantially parallel planes and a polygonal peripheral surface formed by side surfaces substantially perpendicular to the planes and joining conjunctively at cutting corners of the polygon, wherein at least one of the top and bottom faces includes:
- a substantially planar land extending continuously about the entire periphery of the polygon and intersecting each of the side surfaces to define peripheral cutting edges extending between cutting corners;
- a substantially planar first ramp surface extending continuously along an intersection with the land and downwardly at a first angle to the planes from an inner boundary of the land;
- a substantially planar [third] second ramp surface extending downwardly at a second angle to the planes from an inner boundary of the first ramp surface;
- substantially planar corner control surfaces, one positioned only at each cutting corner so as to interrupt a portion of the first ramp surface thereby narrowing the width of the first ramp surface in each cutting corner region;
- and
- substantially planar [second] third ramp surfaces, one of each connecting an inner boundary of a corresponding corner control surface to the [third] second ramp surface and interrupting an intersection of the first and [third] second ramp surfaces in each cutting corner region.
Dependencies are inferred from the claim text.