Patents by Inventor Jee S. Cha

Jee S. Cha 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).

  • Multistage pulse tube coolers
    Patent number: 9714776
    Abstract: A cryocooler may comprise a first stage, a second stage and a phase control device. The first stage may define a first volume. The second stage may define a second volume. The phase control device may be positioned between the first stage and the second stage to receive a flow of working fluid between the first stage and the second stage. The phase control device may comprise a flange and a plunger. The flange may be positioned along a longitudinal axis parallel a direction of the working fluid flow. The plunger may be translatable along the longitudinal axis at least partially within the flange. The plunger and the flange may be sized such that the plunger and the flange define a gap there between and a dimension of the gap is determined by a position of the plunger along the longitudinal axis.
    Type: Grant
    Filed: July 1, 2013
    Date of Patent: July 25, 2017
    Assignee: THE AEROSPACE CORPORATION
    Inventors: Sidney W. K. Yuan, Jee S. Cha
  • MULTISTAGE PULSE TUBE COOLERS
    Publication number: 20130283823
    Abstract: A cryocooler may comprise a first stage, a second stage and a phase control device. The first stage may define a first volume. The second stage may define a second volume. The phase control device may be positioned between the first stage and the second stage to receive a flow of working fluid between the first stage and the second stage. The phase control device may comprise a flange and a plunger. The flange may be positioned along a longitudinal axis parallel a direction of the working fluid flow. The plunger may be translatable along the longitudinal axis at least partially within the flange. The plunger and the flange may be sized such that the plunger and the flange define a gap there between and a dimension of the gap is determined by a position of the plunger along the longitudinal axis.
    Type: Application
    Filed: July 1, 2013
    Publication date: October 31, 2013
    Inventors: Sidney W. K. Yuan, Jee S. Cha
  • Multistage pulse tube coolers
    Patent number: 8474272
    Abstract: Various embodiments are directed to multistage pulse tube coolers. In some embodiments, one or more stages of the pulse tube cooler may comprise a control valve positioned between the hot end of the pulse tube and the reservoir. Also, in various embodiments, one or more inter-stage control valves may be positioned between the pulse tubes of consecutive stages.
    Type: Grant
    Filed: November 3, 2009
    Date of Patent: July 2, 2013
    Assignee: The Aerospace Corporation
    Inventors: Sidney W. K. Yuan, Jee S. Cha
  • MULTISTAGE PULSE TUBE COOLERS
    Publication number: 20110100024
    Abstract: Various embodiments are directed to multistage pulse tube coolers. In some embodiments, one or more stages of the pulse tube cooler may comprise a control valve positioned between the hot end of the pulse tube and the reservoir. Also, in various embodiments, one or more inter-stage control valves may be positioned between the pulse tubes of consecutive stages.
    Type: Application
    Filed: November 3, 2009
    Publication date: May 5, 2011
    Applicant: The Aerospace Corporation
    Inventors: Sidney W. K. Yuan, Jee S. Cha