Patents Assigned to Hetherington, Inc.
  • Patent number: 5157242
    Abstract: Six curved hanging electrical heater panels made of tungsten or molybdenum are arranged to form a hollow cylinder, and are supported at their upper ends by electrical connectors. The hanging panels are electrically interconnected at adjacent lower corners by removable links. Six phase electrical current is applied to the hanging panels through the respective upper connectors, with phases of opposite polarities being applied to diametrically opposed panels. The net current flow through the removable links is zero, enabling the links to be designed to fail electrically and/or mechanically before the panels, thereby protecting the panels from electrical burnout and mechanical damage. Each removable link includes a unique arrangement of a link member, two pins, and a wedge which tightly interlocks the pins, link member and panel corners together.
    Type: Grant
    Filed: October 29, 1990
    Date of Patent: October 20, 1992
    Assignee: Hetherington, Inc.
    Inventors: James S. Hetherington, Mark D. Mahone