METHOD OF MAKING BALL STUDS FROM METAL RODS

• US 3,644,973 A
• Filed: 04/07/1970
• Issued: 02/29/1972
• Est. Priority Date: 04/07/1970
• Status: Expired due to Term

• Current Assignee: Michio Abe
• Original Assignee: Michio Abe
• Inventors: Abe, Michio
• Primary Examiner(s): Eager, Thomas H.
• Application Number:
  US05/026,202
• Time in Patent Office: 693 Days
• Field of Search: 29/149.5B,424,441,421 72/256
• US Class Current: 29/898.052
• CPC Class Codes: B21C 23/03 by both direct and backward extrusion
• CPC Class Codes: B21D 41/04 Reducing; Closing
• CPC Class Codes: B21K 1/44 bolts, studs, or the like making screw-thread B21K1/56; making U-bolts B21K1/74
• CPC Class Codes: Y10T 29/49664 Ball making
• CPC Class Codes: Y10T 29/49805 Shaping by direct application of fluent pressure
• CPC Class Codes: Y10T 29/49812 Temporary protective coating, impregnation, or cast layer
• CPC Class Codes: Y10T 29/49853 of sphere, i.e., ball, in socket

Abstract

A method of making a ball stud from a metal rod, comprising the steps of cutting from the metal rod, a blank having generally the same volume and outer diameter as that of a finished ball stud, forwardly extruding one end of the blank positioned within a die cavity to form a taper, stem and shank portions, forming a preliminary cylindrical shape with a shallow cavity on the other end of the blank, the diameter of said preliminary cylindrical portion being smaller than the outer diameter of a finished spherical head, backwardly extruding the other end to form a preliminary cylindrical shape having a wall of generally the same thickness as that of a finished spherical head portion, and upsetting the preliminary cylindrical shape to form a spherical hollow head portion in the die cavity, whereby the upsetting operation is achieved with an application of a mixture of oil and air to pressurize the inner space of the spherical hollow head portion.

Claims

1. A method of making a ball stud from a metal rod, comprising the steps of:

1. cutting from said metal rod, a blank having generally the same volume and outer diameter as that of a finished ball stud, 2. forwardly extruding one end of said blank positioned within a die cavity to form a taper, stem and shank portions, 3. forming a preliminary cylindrical shape with a shallow cavity on the other end of said blank, the diameter of said preliminary cylindrical portion being smaller than the outer diameter of a finished spherical head, 4. backwardly extruding said other end to form a preliminary cylindrical shape having a wall of generally the same thickness as that of a finished spherical head portion, and 5. upsetting said preliminary cylindrical shape to form a spherical hollow head portion in the die cavity.

2. A method of making ball studs as specified in claim 1 wherein the upsetting operation comprises the step of applying a mixture of oil and air into the cavity of the head portion to pressurize the inner space of the spherical hollow head portion.

3. forming a preliminary cylindrical shape with a shallow cavity on the other end of said blank, the diameter of said preliminary cylindrical portion being smaller than the outer diameter of a finished spherical head,

4. A method of making a ball stud from a metal rod, comprising the steps of:

cutting from said metal rod, a blank having generally the same volume and outer diameter as that of a finished ball stud, forwardly extruding one end of said blank positioned within a die cavity to form a taper, stem and shank portions, forming a preliminary cylindrical shape with a shallow cavity on the other end of said blank, the diameter of said preliminary cylindrical portion being smaller than the outer diameter of a finished spherical head, backwardly extruding said other end to form a preliminary cylindrical shape having a wall of generally the same thickness as that of a finished spherical head portion, and upsetting said preliminary cylindrical shape to form a spherical hollow head portion in the die cavity and to leave a relatively small top hole at the upper end of the finished spherical head.

5. upsetting said preliminary cylindrical shape to form a spherical hollow head portion in the die cavity.