Patents by Inventor Robert K. Stevens

Robert K. Stevens 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: 8019559
    Abstract: A flow meter and method for measuring flow in liquids which may have entrained bubbles or foreign matter. The meter performs alternate transit time and Doppler measurements. The transit time measurements are used to calculate flow so long as they are successful. If the transit time measurements are not successful, the Doppler measurements are used.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: September 13, 2011
    Assignee: Racine Federated, Inc.
    Inventors: Robert K. Stevens, Richard L. Little, William W. Roeber
  • Patent number: 7130750
    Abstract: A variable area flow meter has a magnet carried by a piston which is moved to a position representing fluid flow. An array of magnetoresistive bridge sensors adjacent the path of magnet movement senses the magnet position. The bridges are unbalanced by the magnet field. The analog unbalance signals are read and processed in digital form to develop a flow signal. The flow meter circuits are powered from a 4–20 MA current loop or a remote power supply. Each bridge sensor is powered only when the bridge unbalance signal is being read, to minimize the power requirement.
    Type: Grant
    Filed: March 22, 2005
    Date of Patent: October 31, 2006
    Assignee: Racine Federated, Inc.
    Inventors: Robert K. Stevens, Jonathan Ray McClain, Richard Little
  • Patent number: 6780818
    Abstract: The present invention concerns a quantitative organic vapor-particle sampler which can efficiently sample both semi-volatile organic gases and particulate components through the use of a unique sorbent resin coating and process. The sampler of the present invention comprises in its broadest aspect a tubular device having an inlet at one end through which organic vapor/particles are introduced, an outlet at the other end through which gases exit, at least one annular denuder interposed there between which is coated on the inside surface of the annulus with a specially prepared resin absorbent, which selectively absorbs organic vapors contained in the gases introduced into the inlet, and a filter which traps and collects particles.
    Type: Grant
    Filed: April 10, 2001
    Date of Patent: August 24, 2004
    Assignee: The Regents of the University of California
    Inventors: Lara Gundel, Joan M. Daisey, Robert K. Stevens
  • Publication number: 20010045000
    Abstract: The present invention concerns a quantitative organic vapor-particle sampler which can efficiently sample both semi-volatile organic gases and particulate components through the use of a unique sorbent resin coating and process.
    Type: Application
    Filed: April 10, 2001
    Publication date: November 29, 2001
    Inventors: Lara A. Gundel, Joan M. Daisey, Robert K. Stevens
  • Patent number: 6226852
    Abstract: A method for fabricating a quantitative organic vapor-particle sampler for efficient sampling, detection and quantitation of semi-volatile organic gases, vapors and particulate components. The sampler comprises a diffusion chamber and at least one annular denuder of which surface is coated with a macroreticular resin agglomerates which selectively absorbs organic gases, vapors or particulate matter present in tested samples.
    Type: Grant
    Filed: June 2, 1998
    Date of Patent: May 8, 2001
    Assignee: The Regents of the University of California
    Inventors: Lara Gundel, Joan M. Daisey, Robert K. Stevens
  • Patent number: 5763360
    Abstract: A quantitative organic vapor-particle sampler for sampling semi-volatile organic gases and particulate components. A semi-volatile organic reversible gas sorbent macroreticular resin agglomerates of randomly packed microspheres with the continuous porous structure of particles ranging in size between 0.05-10 .mu.m for use in an integrated diffusion vapor-particle sampler.
    Type: Grant
    Filed: April 28, 1995
    Date of Patent: June 9, 1998
    Assignee: The Regents of the University of California
    Inventors: Lara Gundel, Joan M. Daisey, Robert K. Stevens
  • Patent number: 4961966
    Abstract: An inlet apparatus for gas-aerosol sampling comprises an elutriator column and an impactor member. The elutriator column comprises an inlet and an impact accelerator jet outlet, and the inner surface of the column is provided with a coating of polytetrafluoroethylene-containing polymer. The impactor member includes a housing which surrounds the impact accelerator jet outlet and an impactor surface arranged within the housing and opposite the impact accelerator jet outlet. The inner surface of the housing is also provided with a polytetrafluoroethylene-containing polymer coating.
    Type: Grant
    Filed: February 9, 1990
    Date of Patent: October 9, 1990
    Assignee: The United States of America as represented by the Administrator of the Environmental Protection Agency
    Inventors: Robert K. Stevens, Charles Stone
  • Patent number: 4902318
    Abstract: An inlet apparatus for gas-aerosol sampling comprises an elutriator column and an impactor member. The elutriator column comprises an inlet and an impact accelerator jet outlet, and the inner surface of the column is provided with a coating of polytetrafluoroethylene-containing polymer. The impactor member includes a housing which surrounds the impact accelerator jet outlet and an impactor surface arranged within the housing and opposite the impact accelerator jet outlet. The inner surface of the housing is also provided with a polytetrafluoroethylene-containing polymer coating.
    Type: Grant
    Filed: May 25, 1988
    Date of Patent: February 20, 1990
    Assignee: The United States of America as represented by the Administrator of the Environmental Protection Agency
    Inventors: Robert K. Stevens, Charles Stone