Patents by Inventor H. Michael Hughes

H. Michael Hughes 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).

  • Hydrofluorocarbon refrigerants for use in centrifugal chillers
    Patent number: 6576153
    Abstract: This invention relates to hydrofluorocarbons useful in refrigeration and heat pump applications. The invention provides hydrofluorocarbons selected from the group of 1,1,2,3,3-pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,1,2,3-pentafluoropropane, and mixtures thereof that are environmentally suitable replacements for chlorofluorocarbons in refrigeration applications such as multi-stage centrifugal chillers.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: June 10, 2003
    Assignee: AlliedSignal Inc.
    Inventors: H. Michael Hughes, Mark W. Spatz, Rajiv Ratna Singh
  • Hydrofluorocarbon refrigerants for use in centrifugal chillers
    Publication number: 20020003224
    Abstract: This invention relates to hydrofluorocarbons useful in refrigeration and heat pump applications. The invention provides hydrofluorocarbons selected from the group of 1,1,2,3,3-pentafluoropropane, 1,1,1,3,3-pentafluoropropane, 1,1,1,2,3-pentafluoropropane, and mixtures thereof that are environmentally suitable replacements for chlorofluorocarbons in refrigeration applications such as multi-stage centrifugal chillers.
    Type: Application
    Filed: April 23, 2001
    Publication date: January 10, 2002
    Inventors: H. Michael Hughes, Mark W. Spatz, Rajiv Ratna Singh
  • Method and apparatus to reduce fractionation of fluid blend during storage and transfer
    Patent number: 6234352
    Abstract: A method and apparatus for storing and dispensing in liquid form a blend of fluids which normally fractionate upon boiling. The apparatus includes a container having an internal bladder dividing the container into two chambers. The first chamber contains the liquid blend, and the second chamber contains a pressurizing fluid in sufficient quantity to maintain the pressure on the other side of the bladder in the first chamber above the bubble point pressure of the liquid blend. In this manner, the vapor space above the fluid blend is eliminated, and thus the effect of fractionation caused by vaporization is essentially eliminated during dispensing or leakage of the blend from the package.
    Type: Grant
    Filed: August 10, 1999
    Date of Patent: May 22, 2001
    Assignee: AlliedSignal Inc.
    Inventors: Robert G. Richard, Rajiv Ratna Singh, H. Michael Hughes