Patents by Inventor Gilbert I. Cardwell

Gilbert I. Cardwell 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).

  • Publication number: 20020047623
    Abstract: A starter circuit particularly suitable for a plasma of an ion engine for a spacecraft includes a power supply having an output inductor with a tap. A switch is coupled to the tap. The switch has a control input. A pulse control logic circuit is coupled to said control input, said pulse control logic circuit controlling said switch to an off state to generate a high voltage discharge.
    Type: Application
    Filed: August 22, 2001
    Publication date: April 25, 2002
    Applicant: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Thomas K. Phelps
  • Publication number: 20020047622
    Abstract: A starter circuit particularly suitable for a plasma of an ion engine for a spacecraft includes a power supply having an output inductor with a tap. A switch is coupled to the tap. The switch has a control input. A pulse control logic circuit is coupled to said control input, said pulse control logic circuit controlling said switch to an off state to generate a high voltage discharge.
    Type: Application
    Filed: August 22, 2001
    Publication date: April 25, 2002
    Applicant: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Thomas K. Phelps
  • Patent number: 6369521
    Abstract: A starter circuit particularly suitable for a plasma of an ion engine for a spacecraft includes a power supply having an output inductor with a tap. A switch is coupled to the tap. The switch has a control input. A pulse control logic circuit is coupled to said control input, said pulse control logic circuit controlling said switch to an off state to generate a high voltage discharge.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: April 9, 2002
    Assignee: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Jr., Thomas K. Phelps
  • Patent number: 6369520
    Abstract: A starter circuit particularly suitable for a plasma of an ion engine for a spacecraft includes a power supply having an output inductor with a tap. A switch is coupled to the tap. The switch has a control input. A pulse control logic circuit is coupled to said control input) said pulse control logic circuit controlling said switch to an off state to generate a high voltage discharge.
    Type: Grant
    Filed: August 22, 2001
    Date of Patent: April 9, 2002
    Assignee: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Jr., Thomas K. Phelps
  • Patent number: 6304040
    Abstract: A starter circuit particularly suitable for a plasma of an ion engine for a spacecraft includes a power supply having an output inductor with a tap. A switch is coupled to the tap. The switch has a control input. A pulse control logic circuit is coupled to said control input, said pulse control logic circuit controlling said switch to an off state to generate a high voltage discharge.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: October 16, 2001
    Assignee: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Jr., Thomas K. Phelps
  • Patent number: 6181585
    Abstract: A power supply circuit for an ion engine suitable for a spacecraft is coupled to a bus having a bus input and a bus return. The power supply circuit has a first primary winding of a first transformer. An upper inverter circuit is coupled to the bus input and the first primary winding. The power supply circuit further includes a first lower inverter circuit coupled to the bus return and the first primary winding. The second primary winding of a second transformer is coupled to the upper inverter circuit. A second lower inverter circuit is coupled to the bus return and the second primary winding.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: January 30, 2001
    Assignee: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, Jr., Thomas K. Phelps
  • Patent number: 6154383
    Abstract: A power supply circuit for an ion engine suitable for a spacecraft has a voltage bus having input line and a return line. The power supply circuit includes a pulse width modulation circuit. A plurality of bridge inverter circuits is coupled to the bus and the pulse width modulation circuit. The pulse width modulation circuit generates operating signals having a variable duty cycle. Each bridge inverter has a primary winding and a secondary winding. Each secondary winding is coupled to a rectifier bridge. Each secondary winding is coupled in series with another of the plurality of rectifier bridges.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: November 28, 2000
    Assignee: Hughes Electronics Corporation
    Inventor: Gilbert I. Cardwell, Jr.
  • Patent number: 6111358
    Abstract: A traveling wave tube incorporates a collector having a plurality of collector electrodes, one or more of which is operated at a potential below that of the cathode so as to collect electrons having associated energies greater than the cathode potential (E.sub.K), and thereby act as a high impedance current source. The current from the collector electrode operated below the cathode potential (E.sub.K) is converted by a power converter to an alternating current signal that can be either magnetically coupled to the high voltage transformer (T.sub.1) of the traveling wave tube power supply, or coupled to an external load with a transformer (T.sub.2), thereby improving the operating efficiency of the traveling wave tube system.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: August 29, 2000
    Assignee: Hughes Electronics Corporation
    Inventors: Gilbert I. Cardwell, John A. Collins, Thomas K. Phelps, Xiaoling Zhai
  • Patent number: 5218522
    Abstract: An unregulated D.C. input voltage (V.sub.IN) is processed by a high power chopper (34,36) to produce a first chopped signal having the same voltage as the input (V.sub.IN), and by a low power chopper (56,58) to produce a second chopped signal in synchronism with and having a lower voltage than the first chopped signal. The first and second chopped signals are algebraically combined by transformers (52,54) to produce an A.C. output signal which may be converted to D.C. (V.sub.OUT). The second chopped signal may be controlled to have the same polarity relative to the first chopped signal in which case the voltages add to increase the output voltage (V.sub.OUT), or to have the opposite polarity relative to the first chopped signal in which case the voltages subtract to decrease the output voltage (V.sub.OUT). The periods of addition and subtraction are alternated within the period of the first chopped signal.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: June 8, 1993
    Assignee: Hughes Aircraft Company
    Inventors: Thomas K. Phelps, Khanh T. Le, Gilbert I. Cardwell, Jr.
  • Patent number: 4943903
    Abstract: Regulation of an AC or DC voltage is achieved by processing a major portion of the prime power through a square wave inverter and a small portion of the prime power through a pulse width modulated switching regulator. The methods of regulation generally comprises the steps of: processing the unregulated input voltage to provide an output voltage; regulating an unregulated portion of the input voltage in response to a feedback signal indicative of the output voltage to provide a regulating voltage; and combining the regulating voltage with the output voltage to generate a regulated output voltage. The regulator circuit includes a square wave inverter circuit that produces a voltage in an output transformer, while a pulse width modulator regulates the output voltage in response to a feedback signal.
    Type: Grant
    Filed: March 14, 1989
    Date of Patent: July 24, 1990
    Inventor: Gilbert I. Cardwell, Jr.
  • Patent number: 3962626
    Abstract: An inverter circuit having drive transistors which are turned on by logic signal inputs, the drive transistors supply base current to output transistors, when these output transistors are turned on, current is permitted to flow through a current feedback transformer to supply regenerative base current to drive the output transistors into saturation. By using this current feedback technique, the efficiency of the inverter is greatly increased because no more base drive current is being delivered to the output transistors than is required. The inverter of the present invention also uses feedback loops from the base of the output transistors to the secondary of the current feedback transformer to sink the stored charge from the base emitter region of the output transistors so as to turn the transistors off rapidly.
    Type: Grant
    Filed: November 26, 1974
    Date of Patent: June 8, 1976
    Assignee: Hughes Aircraft Company
    Inventor: Gilbert I. Cardwell
  • Patent number: 3956638
    Abstract: An indefinite number of batteries is connected in parallel to provide current to share a load. Each individual battery current is compared to an average value to regulate each battery controller so that each battery supplies its share of the current.
    Type: Grant
    Filed: December 20, 1974
    Date of Patent: May 11, 1976
    Assignee: Hughes Aircraft Company
    Inventors: Allan F. Ahrens, Gilbert I. Cardwell