Patents by Inventor Robert J. Marquardt

Robert J. Marquardt 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).

  • Roller assembly for sliding doors
    Patent number: 3959849
    Abstract: A roller assembly for sliding doors having a pair of housings one within the other with a coil spring yieldingly urging the inner housing in a direction away from the outer housing, the inner housing supporting a wheel that extends beyond the housing. Tabs are struck on the side walls of the outer housing limiting the outer movement of the inner housing and for the securing of the assembly in a sliding door frame.
    Type: Grant
    Filed: August 8, 1975
    Date of Patent: June 1, 1976
    Assignee: Miller Industries, Inc.
    Inventor: Robert J. Marquardt