Patent ID: 6893354

Claim:
A method of manufacturing cold-forged wing nuts comprising the following steps: (a) rolling and compressing material into linear columns, each said column comprising a plurality of wing material units connected to each other, and each said column of wing material units having an intermediate portion formed as a bulky flat column with opposing projecting wings; (b) shearing said linear columns so that said plurality of wing material units are separated into individual independent wing material units, said shearing being achieved by scissors controlled by a shearing mold and a cam of a shearing machine, each said wing material unit becoming a roughly-shaped material unit after shearing; (c) flattening by forging two sheared uneven sides of each said material unit, each said material unit maintaining an intermediate portion in the form of a flat column with opposing projecting wings; (d) forming insert grooves by compressing opposite sides of a center of said intermediate portion inward to form a recessed groove with an obtuse angle on a first side, and a roughly-shaped insert groove on a second side, said roughly-shaped insert groove then being pressed toward said recessed groove to form trapezoidal insert grooves; (e) compressing and trimming each said material unit so that said opposing projecting wings are compressed inward and forged with two symmetrical recessed grooves, said two recessed grooves respectively formed with an obtuse angle, said two recessed grooves each having a circumferential edge forged outward and trimmed, each said material unit thereby becoming a half-finished product; (f) punching said two recessed grooves of said half-finished product so as to form a through hole in said material unit; (g) forging said opposing projecting wings into two curved wings; and, (h) cutting threads into said through hole to form a finished wing nut.