Patents Assigned to Columbia Manufacturing Corp.
  • Patent number: 7121004
    Abstract: A security door for a gate or building opening is formed of a metal frame that defines a pair of hollow stile frame members and upper and lower hollow transverse rail frame members. Each of the frame members has an inner face with an attachment flange projecting therefrom. Security receiving apertures are defined in the inner faces of the frame members. In the fabrication of the door a plurality of metal security bars are positioned relative to the hollow frame member so that the ends of the security bars project through the security bar receiving apertures and into the hollow frame members. The security bars pass over and reside in contact with the attachment flanges. The security bars are spot welded to the attachment flanges so as to permanently secure them to the door frame. Also, the frame itself is preferably formed from a single, elongated strip of metal that is roll formed and then bent at mitered corner cuts to create and delineate the stile and rail members.
    Type: Grant
    Filed: June 3, 1999
    Date of Patent: October 17, 2006
    Assignee: Columbia Manufacturing Corp.
    Inventor: Curtis C. Shoup
  • Patent number: 5979137
    Abstract: A security door for a gate or building opening is formed of a metal frame that defines a pair of hollow stile frame members and upper and lower hollow transverse rail frame members. Each of the frame members has an inner face with an attachment flange projecting therefrom. Security receiving apertures are defined in the inner faces of the frame members. In the fabrication of the door a plurality of metal security bars are positioned relative to the hollow frame member so that the ends of the security bars project through the security bar receiving apertures and into the hollow frame members. The security bars pass over and reside in contact with the attachment flanges. The security bars are spot welded to the attachment flanges so as to permanently secure them to the door frame. Also, the frame itself is preferably formed from a single, elongated strip of metal that is roll formed and then bent at mitered corner cuts to create and delineate the stile and rail members.
    Type: Grant
    Filed: November 24, 1997
    Date of Patent: November 9, 1999
    Assignee: Columbia Manufacturing Corp.
    Inventor: Curtis C. Shoup