Patents by Inventor Annette M. Schmidt

Annette M. Schmidt 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).

  • Method and apparatus for detecting low refrigerant charge
    Patent number: 5150584
    Abstract: In an air conditioning system, thermistors measure evaporator inlet and outlet temperatures and compressor body temperature. When the differential between inlet and outlet temperatures is below a first threshold and the compressor temperature is above a second threshold, very low refrigerant charge is indicated and the compressor is turned off. Also, if compressor temperature reaches a critical value, the compressor is turned off regardless of the temperature differential across the evaporator.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: September 29, 1992
    Assignee: General Motors Corporation
    Inventors: Glenn E. Tomasov, Annette M. Schmidt