Patents by Inventor Joel A. Donahue

Joel A. Donahue 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).

  • DC-to-DC converter using SCRS with natural commutation
    Patent number: 5216683
    Abstract: A DC-to-DC converter using an SCR bridge receives a first DC power signal and generates a current pulse train in response thereto. The current pulse train is supplied to a rectifying bridge which generates the second DC power signal in response thereto. A single capacitor means is placed between the leads of the output rectifier bridge to aid the commutation of the SCR bridge.
    Type: Grant
    Filed: November 13, 1991
    Date of Patent: June 1, 1993
    Assignee: Coherent, Inc.
    Inventor: Joel A. Donahue
  • Method and apparatus for controlling the power supply of a laser operating in a pulse mode
    Patent number: 5142544
    Abstract: An electronics controller for controlling the power supply of a laser operating in a pulse mode is disclosed. The power supply is of the type having resonant DC converter, charging a capacitive storage means with an inverter stage driving the laser discharge tube. The current supplied to the laser discharge tube is monitored. In addition, the voltage of the capacitive storage means is also measured. Set points for the current, the voltage, and on/off are provided to the electronics controller as the comparison points for the controller. Based upon the voltage and current detected, and the set points provided, the controller controls the on/off of the converter and its frequency, and the on/off of the inverter.
    Type: Grant
    Filed: September 9, 1991
    Date of Patent: August 25, 1992
    Assignee: Coherent, Inc
    Inventors: Joel A. Donahue, Alan M. Neech
  • Method and apparatus for controlling the power supply of a laser operating in a pulse mode
    Patent number: 5048033
    Abstract: An electronics controller for controlling the power supply of a laser operating in a pulse mode is disclosed. The power supply is of the type having a resonant DC converter, charging a capacitive storage means with an inverter stage driving the laser discharge tube. The current supplied to the laser discharge tube is monitored. In addition, the voltage of the capacitive storage means is also measured. Set points for the current, the voltage, and on/off are provided to the electronics controller as the comparison points for the controller. Based upon the voltage and current detected, and the set points provided, the controller controls the on/off of the converter and its frequency, and the on/off of the inverter.
    Type: Grant
    Filed: September 4, 1990
    Date of Patent: September 10, 1991
    Assignee: Coherent, Inc.
    Inventors: Joel A. Donahue, Alan M. Neech