Speed Measuring Apparatus for Indicating Percentage of Nominal Full Speed, Acceleration and Deceleration.
Patent, Filed 20 May 81, patented 27 Jul 82,
DEPARTMENT OF THE NAVY WASHINGTON DC
Pagination or Media Count:
A speed measuring apparatus is provided for indicating a percentage of nominal full speed RPM of a jet engine and also for indicating time required for accelerating and decelerating the engine. A generator output is converted to a square wave and a time interval measurement is made between zero crossings of the square wave. The square wave controls the starting and stopping of a time period counter and measured time is converted to percent RPM which is displayed on a digital incandescent display. Similar time periods are measured when the engine is advanced from idle to full power, and also when the engine is retarded from full power to idle.
- Test Facilities, Equipment and Methods