Patents by Inventor Dewey D. Rigg

Dewey D. Rigg has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Security gratings and methods of making bars therefor
    Patent number: 5133123
    Abstract: A security grating of the type comprising an openwork grid is described. It comprises horizontal bars and vertical rods. The rods pass through openings in the bars. At the each intersection between a bar and rod, a set of tabs locks the bars against movement relative to the rod. A method is described for making these rods from common, rolled round rod stock. A four element punch is employed to displace, or swage, the rod material outwardly to form the tabs in an economical manner.
    Type: Grant
    Filed: September 19, 1990
    Date of Patent: July 28, 1992
    Assignee: Stewart-Decatur Security Systems, Inc.
    Inventor: Dewey D. Rigg