Method and apparatus for knurling a workpiece, method of molding an article with such workpiece, and such molded article
Assignee3M Innovative Properties Company
InventorsTimothy L. Hoopman, Stanley B. Collins, James A. Servatius
Life of this patent
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Abstract
A method and apparatus for knurling a workpiece in which the knurl pattern has an oblique helix angle relative to the longitudinal axis of the cylindrical workpiece. Also disclosed is a method of molding a molded article with the knurled workpiece to impart the inverse of the knurl pattern onto the molded article, such a molded article, a method of forming a structured abrasive article with the molded article, and such an abrasive article.
Claims35
A method of knurling a workpiece, the workpiece having a longitudinal axis, the method comprising the steps of:
- a) imparting a first plurality of grooves to the workpiece, wherein the first plurality of grooves have a first groove helix angle with respect to a reference plane normal to the longitudinal axis of the workpiece;
- b) imparting a second plurality of grooves to the workpiece, wherein the second plurality of grooves have a second groove helix angle with respect to the reference plane, the second plurality of grooves intersecting the first plurality of grooves, thereby imparting a knurl pattern to the outer surface of the workpiece, wherein the pattern is continuous and uninterrupted around the circumference of the workpiece, and wherein the first and second groove helix angles are of substantially unequal magnitude.
A knurled workpiece having a knurled, cylindrical outer surface, the knurled workpiece comprising:
- a cylindrical body having a longitudinal axis and an outer cylindrical surface, said outer surface having a knurl pattern thereon;
- wherein said knurl pattern comprises
- a first plurality of grooves, said first plurality of grooves having a first groove helix angle with respect to a reference plane normal to said longitudinal axis of said workpiece;
- a second plurality of grooves, said second plurality of grooves having a second groove helix angle with respect to said reference plane, said second plurality of grooves intersecting said first plurality of grooves;
- and
- wherein said knurl pattern is continuous and uninterrupted around the circumference of said workpiece, and wherein said first and second groove helix angles are of substantially unequal magnitude.
A method of cut knurling a workpiece, the workpiece having a longitudinal axis, the method comprising the steps of:
- a) rotating the workpiece in a first rotational direction about its longitudinal axis,
- b) engaging the workpiece with a first knurling wheel, wherein the first knurling wheel includes a plurality of teeth on a working surface of the knurling wheel, the teeth each including a cutting edge on a first end thereof, and wherein the first knurling wheel is configured so as to engage the workpiece with the cutting edge of the teeth;
- c) traversing the first knurling wheel in a direction parallel to the longitudinal axis of the workpiece, thereby forming a first plurality of grooves in the workpiece;
- d) disengaging the first knurling wheel form the workpiece;
- e) rotating the workpiece in a second rotational direction opposite to the first rotational direction;
- f) engaging the workpiece with a second knurling wheel, wherein the second knurling wheel includes a plurality of teeth on a working surface of the knurling wheel, the teeth each including a cutting edge on a first end thereof, and wherein the second knurling wheel is configured so as to engage the workpiece with the cutting edge of the teeth;
- and
- g) traversing the second knurling wheel in a direction parallel to the longitudinal axis of the workpiece, thereby forming a second plurality of grooves in the workpiece, the second plurality of grooves intersecting the first plurality of grooves, thereby imparting a pattern to the outer surface of the workpiece, wherein the pattern is continuous and uninterrupted around the circumference of the workpiece.
Dependencies are inferred from the claim text.