Patents Assigned to William P. Ketcham
  • Countdown timer
    Patent number: 4451158
    Abstract: A countdown timer designed for counting down predetermined intervals of time and periodically announcing the progressive elapse of the countdown period thru the use of a voice synthesizer. The time interval between the spoken announcements is decreased as the end of the period approaches. An automatic restart period is incorporated which recycles to a predetermined time to begin the countdown again the number of the restart cycle being counted down is displayed.
    Type: Grant
    Filed: January 20, 1983
    Date of Patent: May 29, 1984
    Assignee: William P. Ketcham
    Inventors: Stephen Selwyn, William P. Ketcham