Patents by Inventor Stephen C. Jardin

Stephen C. Jardin 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: 4687617
    Abstract: The inductively formed spheromak plasma can be maintained in a highly stable and controlled fashion. Steady-state operation is obtained by forming the plasma in the linked mode, then oscillating the poloidal and toroidal fields such that they have different phases. Preferably, the poloidal and magnetic fields are 90.degree. out of phase.
    Type: Grant
    Filed: February 20, 1985
    Date of Patent: August 18, 1987
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Alan C. Janos, Stephen C. Jardin, Masaaki Yamada
  • Patent number: 4654184
    Abstract: For toroidal magnetic confinement devices the second region of stability against ballooning modes can be accessed with controlled operation. Under certain modes of operation, the first and second stability regions may be joined together. Accessing the second region of stability is accomplished by forming a bean-shaped plasma and increasing the indentation until a critical value of indentation is reached. A pusher coil, located at the inner-major-radius side of the device, is engaged to form a bean-shaped poloidal cross-section in the plasma.
    Type: Grant
    Filed: August 30, 1984
    Date of Patent: March 31, 1987
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Morrell S. Chance, Stephen C. Jardin, Thomas H. Stix, Ray C. Grimm, deceased, Janardhan Manickam, Michio Okabayashi
  • Patent number: 4476085
    Abstract: This invention relates to passive conducting loops for stabilizing a plasma ring against unstable tilting and/or shifting modes. To this end, for example, plasma ring in a spheromak is stabilized by a set of four figure-8 shaped loops having one pair on one side of the plasma and one pair on the other side with each pair comprising two loops whose axes are transverse to each other.
    Type: Grant
    Filed: February 26, 1982
    Date of Patent: October 9, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Stephen C. Jardin, Uffe R. Christensen
  • Patent number: 4436691
    Abstract: An inductive method and apparatus for forming detached spheromak plasma using a thin-walled metal toroidal ring, with external current leads and internal poloidal and toroidal field coils located inside a vacuum chamber filled with low density hydrogen gas and an external axial field generating coil. The presence of a current in the poloidal field coils, and an externally generated axial field sets up the initial poloidal field configuration in which the field is strongest toward the major axis of the toroid. The internal toroidal-field-generating coil is then pulsed on, ionizing the gas and inducing poloidal current and toroidal magnetic field into the plasma region in the sleeve exterior to and adjacent to the ring and causing the plasma to expand away from the ring and toward the major axis. Next the current in the poloidal field coils in the ring is reversed. This induces toroidal current into the plasma and causes the poloidal magnetic field lines to reconnect.
    Type: Grant
    Filed: March 24, 1981
    Date of Patent: March 13, 1984
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Stephen C. Jardin, Masaaki Yamada, Harold P. Furth, Mitcheo Okabayashi