Kennametal Inc.

Scott W Vogel

Robert L Shomaker

Kenneth G DeRoche

Earl L Griffin

Jeffrey E Hartshorn

William E Smith

Craig S Adcock

Jeremy L Fowler

An adjustable lead angle toolholder is disclosed for selectively cutting a workpiece at 30.degree., 45.degree., or 60.degree. angles. The toolholder may have a rotatable, cylindrical endmill body that includes a radially-oriented wall or a stationary, square shank having a planar wall on its distal end. The toolholder further includes a cutting insert having at least one linear cutting edge, and a mounting assembly for pivotally mounting the insert onto the wall of the endmill body such that a lead angle of the linear cutting edge is adjustable with respect to the outer periphery of the toolholder body. The mounting assembly includes a plate-shaped insert holder, and a fastener for pivotally connecting the insert holder to the wall of the toolholder body. A locking screw secures the plate-shaped insert holder at a selected pivoted position on the wall of the toolholder body. The invention allows a single toolholder to cut or chamfer a workpiece at different angles.

Adjustable lead angle chamfering toolholder

A cutting insert for use in a rotary milling tool is provided. The cutting insert includes an insert body including a bottom face, a top face, and a side face. A stepped cutting edge is formed at the intersection of the top face and the side face for engaging a workpiece and removing a chip from it. The stepped cutting edge includes at least two offset edge portions which produce distinct, transversely-spaced chip segments during the cutting operation. The offset edge portions are connected by transition edge portions which are disposed at an obtuse angle with respect to the offset edge portions. The angle of the transition edge portions tends to spread the individual chip segments apart during the machining operation to effect a thinning of the chip between the individual chip segments. The entire cutting edge is helically curved so that the cutting edge lies on the surface of a circumscribing cylinder defined by the rotation of the cutting edge about the axis of the milling cutter.

Helical cutting insert with offset cutting edges

An insert for use in a ball nose end mill is provided that includes an insert body having a top wall, a bottom wall, and at least one arcuate side wall. An arcuate cutting edge is defined at an intersection between the top and side walls that includes a plurality of sinusoidal undulations for reducing cutting forces, and vibration, and enhancing the breaking and removal of chips removed from a workpiece during a cutting operation. An end portion of the insert crosses the axis of rotation when the insert is mounted in the seat of an end mill body, and the undulations reduce the considerable shear forces applied to the cutting edge at this location. The cutting edge has a profile which follows the contour of a sphere to permit machining a rounded cut. The side wall of the insert body includes an upper relief portion disposed directly under the cutting edge, with a relief angle for preventing the undulations from making unwanted striations or tool marks in the sidewalls of the rounded cut.

Insert for ball nose end mill

Insert having sinusoidal undulations for ball nose end mill

A milling cutter for cutting a workpiece in both right and left-handed rotary directions is provided that comprises a rotatable cutter body having at least one pair of right and left-handed insert seats disposed on its periphery, an indexable wedge for each pair of right and left-handed insert seats, and a mounting screw for each of the wedges for securing the wedges in a clamping position with respect to a right or left-handed insert seat. Each of the wedges may be used to secure an insert in the right or left-handed seat of its respective seat pair by loosening or removing the mounting screw, and turning the wedge 180.degree.. Each wedge includes a front end for wedgingly engaging an insert in either the right or left-handed seat, and a back end for wedgingly engaging an opposite surface of the unused insert seat in order to more securely clamp the insert in place. The back end of each wedge includes an offset portion that is receivable in and semi-complementary in shape to the unused insert seat for still more stability.

Growing community of inventors

Raleigh, NC, United States of America

Scott W Vogel