Patents by Inventor Robert D. Thorson

Robert D. Thorson 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).

  • Patent number: 5003159
    Abstract: A food service system for serving meals that include hot foods. The system comprises at least one generally circular dish having a top surface for holding the foods that are to be served warm, and a bottom surface, an electrical heating element in the dish for heating the foods on the top surface of the dish, and first and second electrical contacts on the bottom surface of the dish for supplying electrical energy to the heating element. The system further comprises at least one tray, having at least one generally circular well therein for receiving one of the generally circular dishes, and at least one aperture in the well for exposing the first and second electrical contacts on the bottom surface of the dish when the dish is seated in the well. The dish includes at least one foot and the well in the tray includes at least one stop for orienting the dish in the tray to orient the first and second contacts with respect to the aperture.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: March 26, 1991
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: Robert D. Thorson
  • Patent number: 4063068
    Abstract: A portable food serving receptacle capable of heating chilled or frozen food to cooking or serving temperatures and automatically maintaining food at serving temperature. The receptacle consists of thin metallic walls and utilizes a flexible heating element of electrical and thermal insulating material. The heating element is adhered to the metallic walls of an inner dish of the receptacle. The insulating material of the heating element forms a laminated structure in which the electrical resistor is embedded. The walls of the receptacle have a substantially higher thermal conductivity than the laminate. The rate of heat flow from the heating element to the interface of the food and metallic walls of the receptacle is controlled by the thermal insulating characteristics of the laminate so that gradients of heat entering any given point of the food are substantially equal and are maintained at temperature levels below the scorching temperature of the food.
    Type: Grant
    Filed: August 12, 1976
    Date of Patent: December 13, 1977
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: David G. Johnson, Robert D. Thorson