Patents by Inventor Frederick J. Keller

Frederick J. Keller 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 for determining refrigerant charge
    Patent number: 8290722
    Abstract: A method for determining the adequacy of the refrigerant charge in an air conditioning system based upon both the instantaneous degree of subcooling present in the liquid refrigerant in the refrigerant line at a location whereat only liquid refrigerant is present and a calculated average subcooling value based upon accumulated instantaneous subcooling values. The adequacy of the refrigerant charge in the system may be indicated by an alert indicating “check charge” or by a series of lights including a first indicator light indicating that the refrigerant charge is low, a second indicator light indicating that the refrigerant charge is high, and a third indicator light indicating that the refrigerant charge is correct.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: October 16, 2012
    Assignee: Carrier Corporation
    Inventors: Don A. Schuster, Sathish R. Das, Frederick J. Keller, Jr.
  • METHOD FOR DETERMINING REFRIGERANT CHARGE
    Publication number: 20100088046
    Abstract: A method for determining the adequacy of the refrigerant charge in an air conditioning system based upon both the instantaneous degree of subcooling present in the liquid refrigerant in the refrigerant line at a location whereat only liquid refrigerant is present and a calculated average subcooling value based upon accumulated instantaneous subcooling values. The adequacy of the refrigerant charge in the system may be indicated by an alert indicating “check charge” or by a series of lights including a first indicator light indicating that the refrigerant charge is low, a second indicator light indicating that the refrigerant charge is high, and a third indicator light indicating that the refrigerant charge is correct.
    Type: Application
    Filed: December 20, 2006
    Publication date: April 8, 2010
    Applicant: CARRIER CORPORATION
    Inventors: Don A. Schuster, Sathish R. Das, Frederick J. Keller, JR.
  • Run time criteria to control indoor blower speed
    Patent number: 5647533
    Abstract: A method is described of selectively varying the speed of the indoor blower of a heat pump for heating a building or other indoor area when ambient temperature drops below a predetermined level, in order to reduce the cold blow effect of air entering the building. The operating run time fraction of a heating cycle is determined, and the speed of the indoor blower is adjusted when the run time fraction crosses a predetermined threshold value, except that the speed of the indoor blower is maintained when the run time fraction is sufficiently changed compared with a previous run time fraction.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: July 15, 1997
    Assignee: Carrier Corporation
    Inventors: Don A. Schuster, Larry J. Burkhart, Hongmei Liang, Frederick J. Keller, Jr.
  • High to low side bypass to prevent reverse rotation
    Patent number: 5167491
    Abstract: Rotary compressors such as screw compressors and scroll compressors are capable of reverse operation at shutdown as the system pressure seeks to equalize through the running gear. The present invention provides a valved bypass which is opened responsive to the initiation of stopping the compressor. The valve bypass may be located internally or externally with respect to the compressor.
    Type: Grant
    Filed: September 23, 1991
    Date of Patent: December 1, 1992
    Assignee: Carrier Corporation
    Inventors: Frederick J. Keller, Jr., Louis E. Chaump
  • Self-contained solid fuel boiler system
    Patent number: D263417
    Type: Grant
    Filed: November 26, 1979
    Date of Patent: March 16, 1982
    Assignee: Energy Resource Systems, Inc.
    Inventors: Frederick J. Keller, Walter G. Horton
  • Top cover with discharge orifice for the outdoor unit of an air conditioning split system
    Patent number: D349565
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: August 9, 1994
    Assignee: Carrier Corporation
    Inventors: Larry D. Burns, Frederick J. Keller, Jr.