This invention relates to a cutter for a shaper and, more particularly, to a cutter for cutting irregular shapes such as the teeth of a gear. Customarily, such cutters include a body with a plurality of teeth spaced angularly around the periphery of the body. The ends, sides and roots of the teeth are inclined radially inwardly from the face of the body so that the edges of the teeth constitute the cutting edges of the cutter. Frequently, the cutter is surface coated as with a thin film of titanium nitride.
When the cutting edges of most present commercially used shaper cutters become dull, they are resharpened by grinding the face of the tool and hence the faces of the teeth. Such grinding presents a number of difficulties. For one thing, because the ends, sides and roots of the teeth are inclined, the grinding changes the relationship between the cutter and the workpiece and thus the original set-up of the cutter and the work must be adjusted to compensate for this. Also, it is difficult to achieve a high quality of sharpening as compared with the sharpening performed at the point of manufacture. In addition, where the cutter is coated, the cutting edges and surfaces are no longer coated after grinding.
My prior U.S. application Ser. No. 615,775, filed May 31, 1984, now U.S. Pat. No. 4,576,527 discloses a shaper cutter which overcomes the foregoing problems. In the cutter disclosed in that patent, teeth with cutting edges are formed on a thin flexible wafer which is attached to and conforms with the teeth and face of a tool holder, the latter being basically the same as the cutting body of prior cutters and serving to back the cutting teeth of the wafer. When the cutting edges become dull, the thin wafer is simply removed and replaced with a new one. To attach the wafer to the tool holder in conformity with the teeth and face thereof, provision is made of a clamping ring adapted to lie against the end face of the wafer. When a fastener is tightened, the clamping ring flexes the thin wafer into conformity with the tool body and clamps the wafer and the body in assembled relationship.
In the cutter of my patent, the clamping ring projects ahead of the wafer and creates a potential source of axial interference when the cutter is advanced through its cutting stroke. In addition, the clamping ring is not capable of preventing lateral deflection of an extremely thin wafer when heavy cutting forces are exerted on the wafer.
USPTO Backgrounds
USPTO Backgrounds