Patents by Inventor Fang C. Chen

Fang C. Chen 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: 6868678
    Abstract: A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is under-charged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: March 22, 2005
    Assignee: Ut-Battelle, LLC
    Inventors: Viung C. Mei, Fang C. Chen, Esher Kweller
  • Publication number: 20030182950
    Abstract: A non-intrusive refrigerant charge level indicator includes a structure for measuring at least one temperature at an outside surface of a two-phase refrigerant line section. The measured temperature can be used to determine the refrigerant charge status of an HVAC system, and can be converted to a pressure of the refrigerant in the line section and compared to a recommended pressure range to determine whether the system is undercharged, properly charged or over-charged. A non-intrusive method for assessing the refrigerant charge level in a system containing a refrigerant fluid includes the step of measuring a temperature at least one outside surface of a two-phase region of a refrigerant containing refrigerant line, wherein the temperature measured can be converted to a refrigerant pressure within the line section.
    Type: Application
    Filed: March 26, 2002
    Publication date: October 2, 2003
    Inventors: Viung C. Mei, Fang C. Chen, Esher Kweller
  • Patent number: 6467284
    Abstract: A heat pump system having an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant and further having a compressor, an interior heat exchanger, an exterior heat exchanger, a heat pump reversing valve, an accumulator, a thermal expansion valve having a remote sensing bulb disposed in heat transferable contact with the refrigerant piping section between said accumulator and said reversing valve, an outdoor temperature sensor, and a first means for heating said remote sensing bulb in response to said outdoor temperature sensor thereby opening said thermal expansion valve to raise suction pressure in order to mitigate defrosting of said exterior heat exchanger wherein said heat pump continues to operate in a heating mode.
    Type: Grant
    Filed: September 17, 2001
    Date of Patent: October 22, 2002
    Assignee: UT-Battelle, LLC
    Inventors: Fang C. Chen, Viung C. Mei
  • Publication number: 20010032475
    Abstract: An improved non-stratified heat pump water heater wherein the condenser assembly of the heat pump has at least one non-vertical section and is inserted into the water tank through an existing opening in the top of the tank. The condenser assembly has either a tube-in-a-tube style or U-tube style elongated heat exchanger construction. As the refrigerant condenses along the interior surface of the condenser assembly, the heat from the refrigerant is transferred to the water. Two embodiments of the invention include a water heater having a separate sacrificial anode rod and a water heater wherein the condenser assembly acts not only as a heat exchanger but also as the sacrificial anode in the water tank by being constructed of a metal which is more likely to corrode than the metal of the tank.
    Type: Application
    Filed: May 17, 2001
    Publication date: October 25, 2001
    Inventors: Fang C. Chen, Ronald E. Domitrovic, Viung C. Mei, John J. Tomlinson
  • Patent number: 6250090
    Abstract: An apparatus and method for warm-liquid defrosting of the evaporator of a refrigeration system. The apparatus includes a first refrigerant expansion device that selectively expands refrigerant for cooling the evaporator, a second refrigerant expansion device that selectively expands the refrigerant after the refrigerant has passed through the evaporator, and a defrosting control for the first refrigerant expansion device and second refrigerant expansion device to selectively defrost the evaporator by causing warm refrigerant to flow through the evaporator.
    Type: Grant
    Filed: September 15, 1999
    Date of Patent: June 26, 2001
    Assignee: Lockheed Martin Energy Research Corp. Oak Ridge National Laboratory
    Inventors: Viung C. Mei, Fang C. Chen, Ronald E. Domitrovic
  • Patent number: 6233958
    Abstract: An improved heat pump water heater wherein the condenser assembly of the heat pump is inserted into the water tank through an existing opening in the top of the tank, the assembly comprising a tube-in-a-tube construction with an elongated cylindrical outer body heat exchanger having a closed bottom with the superheated refrigerant that exits the compressor of the heat pump entering the top of the outer body. As the refrigerant condenses along the interior surface of the outer body, the heat from the refrigerant is transferred to the water through the outer body. The refrigerant then enters the bottom of an inner body coaxially disposed within the outer body and exits the top of the inner body into the refrigerant conduit leading into the expansion device of the heat pump. The outer body, in a second embodiment of the invention, acts not only as a heat exchanger but also as the sacrificial anode in the water tank by being constructed of a metal which is more likely to corrode than the metal of the tank.
    Type: Grant
    Filed: September 15, 1999
    Date of Patent: May 22, 2001
    Assignee: Lockhead Martin Energy Research Corp.
    Inventors: Viung C. Mei, John J. Tomlinson, Fang C. Chen
  • Patent number: 5845502
    Abstract: A heat pump system includes, in an operable relationship for transferring heat between an exterior atmosphere and an interior atmosphere via a fluid refrigerant: a compressor; an interior heat exchanger; an exterior heat exchanger; an accumulator; and means for heating the accumulator in order to defrost the exterior heat exchanger.
    Type: Grant
    Filed: July 22, 1996
    Date of Patent: December 8, 1998
    Assignee: Lockheed Martin Energy Research Corporation
    Inventors: Fang C. Chen, Viung C. Mei, Richard W. Murphy
  • Patent number: 5622055
    Abstract: A refrigeration system having a vapor compression cycle utilizing a liquid over-feeding operation with an integrated accumulator-expander-heat exchanger. Hot, high-pressure liquid refrigerant from the condenser passes through one or more lengths of capillary tubing substantially immersed in a pool liquid refrigerant in the accumulator-expander-heat exchanger for simultaneously sub-cooling and expanding the liquid refrigerant while vaporizing liquid refrigerant from the pool for the return thereof to the compressor as saturated vapor. The sub-cooling of the expanded liquid provides for the flow of liquid refrigerant into the evaporator for liquid over-feeding the evaporator and thereby increasing the efficiency of the evaporation cycle.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: April 22, 1997
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Viung C. Mei, Fang C. Chen
  • Patent number: 5293130
    Abstract: Apparatus for detecting an electronegative species comprises an analysis chamber, an inlet communicating with the analysis chamber for admitting a sample containing the electronegative species and an ionizable component, a radioactive source within the analysis chamber for emitting radioactive energy for ionizing a component of the sample, a proportional electron detector within the analysis chamber for detecting electrons emitted from the ionized component, and a circuit for measuring the electrons and determining the presence of the electronegative species by detecting a reduction in the number of available electrons due to capture of electrons by the electronegative species.
    Type: Grant
    Filed: July 2, 1991
    Date of Patent: March 8, 1994
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Steve L. Allman, Fang C. Chen, Chung-Hsuan Chen
  • Patent number: 5245833
    Abstract: A refrigeration air conditioning system utilizing a liquid over-feeding operation is described. A liquid refrigerant accumulator-heat exchanger is placed in the system to provide a heat exchange relationship between hot liquid refrigerant discharged from condenser and a relatively cool mixture of liquid and vaporous refrigerant discharged from the evaporator. This heat exchange relationship substantially sub-cools the hot liquid refrigerant which undergoes little or no evaporation across the expansion device and provides a liquid over-feeding operation through the evaporator for effectively using 100 percent of evaporator for cooling purposes and for providing the aforementioned mixture of liquid and vaporous refrigerant.
    Type: Grant
    Filed: May 19, 1992
    Date of Patent: September 21, 1993
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Viung C. Mei, Fang C. Chen
  • Patent number: 5184015
    Abstract: A method for analyzing a gaseous electronegative species comprises the steps of providing an analysis chamber; providing an electric field of known potential within the analysis chamber; admitting into the analysis chamber a gaseous sample containing the gaseous electronegative species; providing a pulse of free electrons within the electric field so that the pulse of free electrons interacts with the gaseous electronegative species so that a swarm of electrically charged particles is produced within the electric field; and, measuring the mobility of the electrically charged particles within the electric field.
    Type: Grant
    Filed: September 27, 1991
    Date of Patent: February 2, 1993
    Assignee: Martin Marietta Energy Systems, Inc.
    Inventors: Steve L. Allman, Chung-Hsuan Chen, Fang C. Chen