Patents by Inventor Fredric F. Ehrich

Fredric F. Ehrich 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: 6392313
    Abstract: The invention overcomes limitations of conventional power and thermodynamic sources by with micromachinery components that enable production of significant power and efficient operation of thermodynamic systems in the millimeter and micron regime to meet the efficiency, mobility, modularity, weight, and cost requirements of many modern applications. A micromachine of the invention has a rotor disk journalled for rotation in a stationary structure by a journal bearing. A plurality of radial flow rotor blades, substantially untapered in height, are disposed on a first rotor disk face, and an electrically conducting region is disposed on a rotor disk face. A plurality of stator electrodes that are electrically interconnected to define multiple electrical stator phases are disposed on a wall of the stationary structure located opposite the electrically conducting region of the rotor disk.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: May 21, 2002
    Assignee: Massachusetts Institute of Technology
    Inventors: Alan H. Epstein, Stephen D. Senturia, Ian A. Waitz, Jeffrey H. Lang, Stuart A. Jacobson, Fredric F. Ehrich, Martin A. Schmidt, G. K. Ananthasuresh, Mark S. Spearing, Kenneth S. Breuer, Steven F. Nagle
  • Patent number: 5932940
    Abstract: The invention provides a micro-gas turbine engine and associated microcomponentry. The engine components, including, e.g., a compressor, a diffuser having diffuser vanes, a combustion chamber, turbine guide vanes, and a turbine are each manufactured by, e.g., microfabrication techniques, of a structural material common to all of the elements, e.g., a microelectronic material such as silicon or silicon carbide. Vapor deposition techniques, as well as bulk wafer etching techniques, can be employed to produce the engine. The engine includes a rotor having a shaft with a substantially untapered compressor disk on a first end, defining a centrifugal compressor, and a substantially untapered turbine disk on the opposite end, defining a radial inflow turbine. The rotor is preferably formed of a material characterized by a strength-to-density ratio that enables a rotor speed of at least about 500,000 rotations per minute.
    Type: Grant
    Filed: November 15, 1996
    Date of Patent: August 3, 1999
    Assignee: Massachusetts Institute of Technology
    Inventors: Alan H. Epstein, Stephen D. Senturia, Ian A. Waitz, Jeffrey H. Lang, Stuart A. Jacobson, Fredric F. Ehrich, Martin A. Schmidt, G. K. Ananthasuresh, Mark S. Spearing, Kenneth S. Breuer, Steven F. Nagle
  • Patent number: 5214585
    Abstract: A low-speed balancing method is provided for balancing a rotor to introduce balance corrections for reducing unbalance due to operation of the rotor at or near critical speeds without actually balancing the rotor at such critical speeds. The method is applicable for balancing a rotor in three, four or more correction planes by utilizing combinations of generic unbalance distributions of the rotor and predetermined mode shapes of the rotor at critical speeds. A simple method is presented which allows an operator using a low-speed balancing machine to determine measured corrections applicable to two planes of the rotor and then the operator effects at least a third correction to the rotor which is proportional to the measured corrections and the unbalance/mode shape combination. The operator then repeats the low-speed balancing sequence to determine final corrections at the two planes, which are then made for finally balancing the rotor.
    Type: Grant
    Filed: June 30, 1989
    Date of Patent: May 25, 1993
    Assignee: General Electric Company
    Inventor: Fredric F. Ehrich