Cutting insert

DETAILED DESCRIPTION With reference to FIG.
1, there is illustrated a cutting insert 11 in accordance with the preferred embodiment of the present invention.
As shown, the cutting insert 11 comprises a polygonal body having substantially parallel surfaces 15, 17 in the form of respective upper and lower surfaces and peripheral side surfaces 19 substantially normal to the upper and lower surfaces 15, 17.
The side surfaces 19 meet to form corners 20 at the ends of the side surfaces 19.
At least one of the parallel surfaces 15, 17 has chip control channels or grooved recesses 21 merging at and descending from each of the respective corners 20 of the polygon.
Channels 21 extend adjacent the peripheral side surfaces 19.
Although the insert 11 shown in the drawings is triangular in shape, it is contemplated that the insert 11 may be in the shape of any polygon such as square, diamond or rectangular.
As further illustrated in FIG.
1, the insert 11 includes a plurality of planar outer land portions 25 associated with and forming at least a pair of cutting edges 26, 28 with each side surface 19.
Cutting edges 26, 28 are formed by the intersection of each of the outer land portions 25 with a respective side surface 19.
Each of the outer land portions 25 forms an angle less than 90.
degree.
or an acute angle with an adjacent peripheral side surface 19.
This first direction is downwardly toward the interior of the insert 11 with a plane normal to a peripheral side surface 19.
The slope of the outer lands 25 in the first direction imparts a positive rake angle to the cutting edges 26, 28.
Each of the outer lands 25 descend downwardly in a second direction from one of the corners 20 along respective peripheral sides surfaces 19 toward an adjacent one of the corners 20.
When the outer land portions 25 are observed from a planar view as illustrated in FIG.
3, each of the outer land portions 25 extends downwardly in the second direction at an acute angle from a respective corner 20.
This angle is shown as angle a in FIG