Abstract: A cumulative running time indicator for use with an engine has a ceramic resonator-controlled oscillator that drives an electronic divider, a multiplexer, and a stepping motor which is connected through a gear train to a mechanical display showing elapsed time. The running time indicator operates only when an electrical generator, which is mechanically coupled with the engine, produces sufficient voltage to operate the indicator circuits. Sufficient voltage is produced at all engine speeds above a threshold speed which is less than engine idling speed. The generator supplies ac voltage to doubler circuit that has two separate outputs -- one for supplying large pulses of current for the stepping motor, and a partially isolated second output for other electronic loads. A tachometer output signal is provided at an auxiliary output terminal and is buffered to prevent disablement of the running time indicator by short circuits and externally applied voltages at the auxiliary output terminal.

Abstract: A digital clock having time display drums, shift pinions to regulate these time display drums, an electric motor, a plurality of gears for transmitting the rotating movement of the electric motor to the time display drums and timer members related to the rotating movement of the time display drum, these components being attached to a frame, in which a plastic mounting and a plastic holding plate, these being a side wall of the frame and arranged in parallel each other, are provided with a plurality of shafts being integrally molded on these plates and rotatably supporting the gears for driving the time display drum, and means being integrally molded on these plates for supporting and guiding the timer member.