Timing devices for clocks or watches for comparing the rate of the

Official title: Timing devices for clocks or watches for comparing the rate of the oscillating member with a standard {(supporting devices for clocks with built-in recording apparatus G04D1/063; measuring short time intervals G04F10/00; frequency measuring in general H04B, G01R)}

G04D7/12 (Timing devices for clocks or watches for comparing the rate of the) appears on 101 US grants and 63 published applications in this corpus.