Patents by Inventor Douglas C. Fortner

Douglas C. Fortner 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: 20100271006
    Abstract: The present invention is a method and system for monitoring the continuous flow of power delivered by multiple DC Direct current operated starter motors used to start engine driven electrical generators. The method and system comprise the closing of a starter battery system and an associated starter control switch, causing the starter battery system to discharge through a shunt whereby current is fed into a starter motor. The shunt is optionally provided as a precision resistor with a pre-calibrated voltage drop in millivolts DC proportional to a current passing through it. The shunt directs current to a meter relay, which is calibrated by establishing two set points, or desired trigger ranges, for the meter relay. If the current falls outside a range established by the two set points, then a meter relay alarm output is activated; and, if the current remains within the range, then the meter relay alarm output is not activated.
    Type: Application
    Filed: April 28, 2010
    Publication date: October 28, 2010
    Applicant: Darby Group Inc.
    Inventor: DOUGLAS C. FORTNER
  • Patent number: 5250904
    Abstract: A stationary battery testing device as provided for measuring imminent battery failure while the battery is in a float mode. The device includes a circuitry for measuring the internal resistance changes of a battery and then comparing them over a predetermined duration of time so as to provide audible or visual discernable signals to indicate an imminent battery failure after the expiration of said predetermined period of time. An additional temperature monitoring component may be provided for the device to monitor internal changes within the battery with respect to temperature. This can also be combined in a temperature compensated automatic adjustment of voltage and alarm thresholds in an active feedback loop to augment and broaden the basis of stationary battery applications where the battery testing device can be used.
    Type: Grant
    Filed: December 16, 1992
    Date of Patent: October 5, 1993
    Assignee: Advanced Power Technology Inc.
    Inventors: Arthur B. Salander, Douglas C. Fortner