Patents by Inventor Ronald T. Keen

Ronald T. Keen 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: 10374527
    Abstract: A circuit for delivering electrical energy to an AC mains connection is disclosed. The circuit includes a voltage source and a switch connected between the voltage source and the AC mains connection. The switch operates to transfer current from the voltage source to the AC mains. The circuit further includes a controller to control the switch. The controller operates to generate a simulated signal that represents a waveform of the AC mains without any distortion present on the waveform of the AC mains.
    Type: Grant
    Filed: December 29, 2014
    Date of Patent: August 6, 2019
    Assignee: Beckman Coulter, Inc.
    Inventors: Jason L. Hessler, Ronald T. Keen
  • Patent number: 9246432
    Abstract: A centrifuge includes a regenerative braking safety system including an electrical system reversibly coupled to a power source. A motor is coupled to the electrical system. The motor is capable of driving a rotor using power delivered through the electrical system, and is further capable of supplying the electrical system with recovered energy. The recovered energy is electrical energy converted from kinetic energy of the rotor during regenerative braking of the motor. The safety system includes a power cut-off configured to disable the effect of regenerative braking of the motor when the electrical system is decoupled from the power source.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: January 26, 2016
    Assignee: Beckman Coulter, Inc.
    Inventors: Ronald T. Keen, Jason L. Hessler
  • Publication number: 20150194913
    Abstract: A circuit for delivering electrical energy to an AC mains connection is disclosed. The circuit includes a voltage source and a switch connected between the voltage source and the AC mains connection. The switch operates to transfer current from the voltage source to the AC mains. The circuit further includes a controller to control the switch. The controller operates to generate a simulated signal that represents a waveform of the AC mains without any distortion present on the waveform of the AC mains.
    Type: Application
    Filed: December 29, 2014
    Publication date: July 9, 2015
    Inventors: Jason L. Hessler, Ronald T. Keen
  • Publication number: 20120206071
    Abstract: A centrifuge includes a regenerative braking safety system including an electrical system reversibly coupled to a power source. A motor is coupled to the electrical system. The motor is capable of driving a rotor using power delivered through the electrical system, and is further capable of supplying the electrical system with recovered energy. The recovered energy is electrical energy converted from kinetic energy of the rotor during regenerative braking of the motor. The safety system includes a power cut-off configured to disable the effect of regenerative braking of the motor when the electrical system is decoupled from the power source.
    Type: Application
    Filed: February 8, 2012
    Publication date: August 16, 2012
    Inventors: Ronald T. Keen, Jason L. Hessler
  • Patent number: 5619276
    Abstract: Adjustment and maintenance of a phase relationship between a video signal and a scan synchronizing signal to assure proper horizontal centering is provided in a horizontal deflection system. A first phase locked loop generates a first timing signal at a first frequency, synchronously with a horizontal synchronizing component in a video signal. A presettable counting circuit operates synchronously with the first timing signal for dividing a clock signal to generate a second timing signal at a second frequency. A second phase locked loop generates a scan synchronizing signal from the second timing signal. A microprocessor may supply different numbers to a register, the output of the register being coupled to the presettable counting circuit. Different numbers change the relative phase between the first and second timing signals by incremental steps.
    Type: Grant
    Filed: March 29, 1993
    Date of Patent: April 8, 1997
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Todd J. Christopher, Ronald T. Keen
  • Patent number: 5339114
    Abstract: A video input signal to be displayed is applied to an offset clamp circuit which effects a DC offset of blanking and active video portions of each video line. The DC offset or shift is of an amount and in a polarity sense to place the black level of the active portion of an NTSC color standard signal at a level corresponding to blanking level of the NTSC color standard. Advantageously, subsequent clamping at the shifted level enables contrast control without altering the black level of displayed images.
    Type: Grant
    Filed: July 29, 1992
    Date of Patent: August 16, 1994
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: William A. Lagoni, Ronald T. Keen, Charles B. Neal
  • Patent number: 5241375
    Abstract: Baseband chrominace components are time division multiplexed and subjected to vertical and horizontal recursive filtering thereby providing color component noise reduction in which vertical streaking characteristic of the vertical recursive filtering is effectively visually cancelled by horizontal streaking characteristic of the horizontal recursive filter thereby providing the benefits of (1) noise reduced baseband chrominance components (2) with minimal visual artifacts, (3) without requiring duplication of filtering elements whereby (4) reliability is increased and with a minimimum of filtering elements and (5) costs are proportionately reducted.
    Type: Grant
    Filed: June 26, 1991
    Date of Patent: August 31, 1993
    Assignee: Thomson Consumer Electronics, Inc.
    Inventor: Ronald T. Keen
  • Patent number: 5237398
    Abstract: Two transistors are operated individually as emitter follower buffer amplifiers for R-Y and B-Y input signals and are operated together as an inverting summing matrix for deriving a G-Y output signal from the R-Y and B-Y input signals. All three output signals are "buffered" (i.e., provided by low impedance sources) and are subject to substantially equal delays. Advantageously, the circuit implementation requires only two transistors and three resistors to provide output signals which are (1) buffered, (2) matrixed and (3) delay compensated and which features improved reliability (due to reduced "parts count") and an economic implementation of the buffering, delay compensation and matrixing functions.
    Type: Grant
    Filed: May 28, 1991
    Date of Patent: August 17, 1993
    Assignee: Thomson Consumer Electronics, Inc.
    Inventors: Ronald T. Keen, Robert L. O'Brien, William A. Lagoni
  • Patent number: 4660084
    Abstract: A television receiver is arranged to selectively display either information from a broadcast television signal or information from an auxiliary video signal, in accordance with the position of a switching network to which the signals are capacitively coupled via respective capacitors. Similar black reference levels are established for the television and auxiliary signals by means of respective clamping circuits, including the coupling capacitors, which operate at different times but with respect to the same clamping reference voltage.
    Type: Grant
    Filed: September 25, 1985
    Date of Patent: April 21, 1987
    Assignee: RCA Corporation
    Inventors: Paul D. Filliman, Leopold A. Harwood, Ronald T. Keen, Robert P. Parker
  • Patent number: 4660085
    Abstract: A television receiver is arranged to selectively display either information from a broadcast television signal, or information from an auxiliary video signal. The black image reference level associated with the broadcast signal information is sampled and used to automatically establish the black image reference level of the auxiliary video signal.
    Type: Grant
    Filed: September 25, 1985
    Date of Patent: April 21, 1987
    Assignee: RCA Corporation
    Inventors: Leopold A. Harwood, Paul D. Filliman, Ronald T. Keen
  • Patent number: 4612577
    Abstract: A television receiver includes an interface network for selectively coupling either a standard broadcast television signal, or auxiliary analog or digital video signals, to an image display device. The interface network includes a keyed circuit for clamping the auxiliary signals. A pulse for keying the clamping circuit exhibits one timing characteristic when analog auxiliary signal are selected for display, and a different timing characteristic when a digital auxiliary signal is selected for display.
    Type: Grant
    Filed: June 26, 1985
    Date of Patent: September 16, 1986
    Assignee: RCA Corporation
    Inventor: Ronald T. Keen
  • Patent number: D679409
    Type: Grant
    Filed: September 1, 2011
    Date of Patent: April 2, 2013
    Assignee: Beckman Coulter, Inc.
    Inventors: Ronald C. Johnson, Katherine Chu, Bradley D. Carstens, Brandon L. Reese, Ronald T. Keen