Production of threaded metal rods for making U-bolts
US4936131A · kind A · utility
Inventor
Key dates
| Filing date | Jun 2, 1989 |
| Grant date | Jun 26, 1990 |
| Priority date | — |
| Expiry date | Jun 2, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB21K1/74
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
Elongated straight cylindrical metal rods are threaded along opposite end portions, and the cylindrical outer surface of the center portion of each rod is marked to form a visual indicator of the longitudinal center of the rod. The straight rods are successively inserted into a rod bending machine having a mandrel with a mark indicating the center plane of the bending operation. The mid-point mark on each rod is aligned with the center plane mark on the machine, and the rod is bent to form a precision U-bolt. Preferably, the mark identifying the center of each rod extends circumferentially around the metal rod and is formed by a stripe of color contrasting ink directly on the rod or on a label attached to the rod to provide a permanent mark which does not require rotating the rod to find the mark.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.