Tool holder having a clamp plate for transmitting clamping forces from a clamping arm to a cutting insert
AssigneeSandvik AB
InventorsSture Sjoo, Per Hansson
Life of this patent
Estimating the term…
Abstract
A cutting insert is clamped in a pocket of a holder by a top clamp assembly which includes a clamp arm screwed to the holder, and a clamp plate interposed between the insert and a front part of the clamp arm. The clamp plate is formed of a harder and more wear-resistant material than the clamp arm and transmits clamping forces from the clamp arm to the cutting insert. The hard clamp plate shields the clamp arm from being impacted by chips generated during a machining operation, thereby minimizing wearing of the clamp arm.
Claims15
A tool comprising:
- a holder including an insert pocket comprised of a bottom surface and at least one side surface upstanding therefrom;
- a cutting insert seated in the pocket against the bottom surface and the at least one side surface, the insert including a top face;
- a clamp plate seated on the cutting insert, the clamp plate including:
- a planar underside engaging the top face of the insert, and
- a through-hole extending upwardly through the underside and completely through the clamp plate, the through-hole having a cross section decreasing downwardly toward the underside;
- a top clamp comprising a clamp arm mounted on the holder and defining a longitudinal axis extending in a direction defining a front/rear direction, the clamp arm including a downwardly projecting rear protrusion engaging a rear portion of the holder, and a downwardly protecting front protrusion extending into the through-hole of the clamp plate and engaging a wall thereof, the clamp plate formed of a harder and more wear resistant material than the clamp arm;
- and
- a clamp screw extending downwardly through the clamp arm and threadedly engaged in a bore formed in the holder for drawing the rear protrusion into engagement with the rear portion of the holder and the front protrusion into contact with the wall of the through-hole.
A clamp plate adapted to transmit downward pressure from a clamp arm to a cutting insert disposed in a pocket of a holder, the clamp plate including top and bottom faces and side faces interconnecting the top and bottom faces, a through-hole extending through the clamp plate from the top face to the bottom face, one of the side faces being wedge shaped, the wedge shape narrowing in a direction away from the through-hole, another of the side faces being convexly curved, a portion of the clamp plate having the wedge-shaped side face being thicker than a portion of the clamp plate having the convexly curved side face.
A method of clamping a cutting insert to a holder, comprising the steps of:
- A) positioning the cutting insert in a pocket of the holder;
- and
- B) mounting a clamp assembly on the holder, whereby a rear portion of a clamp arm of the assembly is attached by a screw to the holder, and a front portion of the clamp arm extends downwardly into a recess formed in a clamp plate of the assembly, the clamp plate formed of a harder and more wear-resistant material than the holder and interposed between the cutting insert and the front portion of the holder to transmit clamping forces from the clamp arm to the insert.
Dependencies are inferred from the claim text.