Patents by Inventor Frank Cathell

Frank Cathell 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: 5342497
    Abstract: The invention provides an electrophoresis system which separates charged chemical substances by means of applying an electrical potential across a buffer solution which includes those chemical substances. The system of the invention includes a power supply and control system which has a wide dynamic range of constant voltage, current and power which may be supplied, and is therefore particularly suited to the needs of the electrophoresis system. In the invention, the power supply includes a flyback topology and a control system which allows an operator to specify a wide range of constant voltage, current or power supply requirements for the electrophoresis system.
    Type: Grant
    Filed: April 8, 1991
    Date of Patent: August 30, 1994
    Assignee: Stratagene Cloning Systems
    Inventors: Frank Cathel, Robert Leshofs
  • Patent number: 5055172
    Abstract: The invention provides an electrophoresis system which separates charged chemical substances by means of applying an electrical potential across a buffer solution which includes those chemical substances. The system of the invention includes a power supply and control system which has a wide dynamic range of constant voltage, current and power which may be supplied, and is therefore particularly suited to the needs of the electrophoresis system. In the invention, the power supply includes a flyback topology and a control system which allows an operator to specify a wide range of constant voltage, current or power supply requirements for the electrophoresis system.
    Type: Grant
    Filed: March 23, 1990
    Date of Patent: October 8, 1991
    Assignee: Stratagene Cloning Systems
    Inventors: Frank Cathel, Robert Leshofs
  • Patent number: 4912597
    Abstract: A capacitor bank includes first and second spaced opposite polarity DC bus bars and first and second spaced printed circuit boards that extend between the bus bars. A single face of the printed circuit boards includes first and second mutually insulated metal cladding segments. Plural first and second main capacitors have first and second opposite polarity electrodes extending from a single face thereof.
    Type: Grant
    Filed: August 9, 1989
    Date of Patent: March 27, 1990
    Assignee: Qualidyne Systems
    Inventors: Ronnie L. Carpenter, Frank Cathell
  • Patent number: 4720775
    Abstract: A high frequency switching regulator drives plural loads by way of an output transformer. The transformer includes plural secondary windings connected to plural loads. One of the secondary windings is connected to a main output channel including a circuit for maintaining the current in the main channel above a predetermined minimum required for proper voltage regulation of the other channels. The circuit includes a current transformer in a line of the main channel. The current transformer contains a saturating core that saturates in response to a main channel current slightly above the predetermined minimum main channel current. An impedance responsive to current in the current transformer loads the main channel so that the main channel current is never less than the predetermined value regardless of the impedance between load terminals of the main channel. This assures proper inverter operation to maintain full voltage regulation of the other output channels.
    Type: Grant
    Filed: June 3, 1986
    Date of Patent: January 19, 1988
    Assignee: Qualidyne Systems, Inc.
    Inventor: Frank Cathell
  • Patent number: 4270165
    Abstract: A plurality of conventional, parallel a.c. to d.c. to a.c. to d.c. converters are driven by a common a.c. source supply current to a common load. Each of the converters includes a controller for a pulse width modulated chopper; the controller determines the amplitude of d.c. current at the output terminals of the particular converter. Input terminals of each controller are responsive to the output voltage of the particular converter with which the controller is associated. A common controller for the controllers of the individual converters is responsive to the load voltage. The common controller varies the impedance of a single variable impedance connected in parallel to remote sense input terminals of the controller of each of the converters.
    Type: Grant
    Filed: April 24, 1979
    Date of Patent: May 26, 1981
    Assignee: Qualidyne Systems, Inc.
    Inventors: Ronnie L. Carpenter, Frank Cathell
  • Patent number: 4105957
    Abstract: A full bridge inverter includes four bipolar transistors of like conductivity type, connected in a bridge circuit including an apex to which a load is connected. During a first time interval, emitter collector paths of a first pair of transistors are connected betwen a DC source and the apex so that current flows in a first direction through the apex while the transistors are forward biased. The emitter collector paths of a second pair of transistors are connected with the source and the apex so that current flows in a second direction through the apex during a second interval while the transistors of the second pair are forward biased. A first transformer has first and second windings respectively connected in series with the emitters of the transistors of the first pair, such that voltages at the emitters of the transistors of the first pair have a tendency to vary in the same direction.
    Type: Grant
    Filed: September 21, 1977
    Date of Patent: August 8, 1978
    Assignee: Qualidyne Systems, Inc.
    Inventor: Frank Cathell