Claims
- 1. A process for forming a fastening element, comprising the steps of:
- providing a cylindrical steel stock;
- cutting a cylindrical piece of steel having a predetermined length from said steel stock;
- bending said cylindrical piece of steel to form a U-shaped body having a first bar-shaped member extending longitudinally along an axial direction, and second and third bar-shaped members extending in parallel to each other along a direction normal to the axial direction of said first bar-shaped member;
- positioning said U-shaped body in a main die such that said second and third bar-shaped members are oriented vertically downward of said first bar-shaped member, wherein said second and third bar shaped members extend through respective holes defined in said main die and respective ends of said second and third bar-shaped members contact an auxiliary die disposed below said main die, such that said first bar-shaped member is disposed a predetermined distance above an upper surface of said main die thereby leaving a gap between said first bar-shaped member and said upper surface of said main die;
- pressing said first bar-shaped member forcibly downward with an upper pressing die, thereby flattening said first bar-shaped member while folding and forcing respective sides thereof outwardly along the axial direction of said first bar-shaped member to form first and second ribs extending outwardly beyond respective connecting positions between said first bar-shaped member and said second and third bar-shaped members; and,
- after pressing commences but before said upper pressing die has completed pressing said first bar-shaped member, lowering said auxiliary die thereby allowing said second and third bar-shaped members to yield while the first bar-shaped member is being pressed.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3-010784 |
Jan 1991 |
JPX |
|
Parent Case Info
This is a continuation-in-part of U.S. application Ser. No. 07/843,888, filed Jan. 31, 1992, now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (4)
Number |
Date |
Country |
110996 |
May 1899 |
DEX |
514092 |
Jan 1938 |
GBX |
855647 |
Dec 1960 |
GBX |
1364159 |
Aug 1974 |
GBX |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
843888 |
Jan 1992 |
|