euclid The Time Traveler's Clock, User Manual

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must be periodically measured to determine if winding is required. As the chronometer
runs down, the winding input stem must be allowed to rotate backwards, so the
chronometer may continue operation. Finally, provision must be made for manually
winding the chronometer.
The successful winding mechanism uses a titanium-geared radio-control servo motor
fitted with a drive pinion. The drive pinion is driven alternately clockwise and
counterclockwise by the servo motor. The Servo Drive Pinion is constantly meshed with
the Winding Rack, which is driven back and forth by the Servo Motor. The Winding Rack
engages a Winding Gear. The Winding Gear rides on the Sinding Spindle, which has a
square opening on its upper end to engage the winding stem of the chronometer.
In order that the back-and-forth motion of the Winding Rack does not force the Winding
Spindle backwards (which would damage the chronometer), a One-way Clutch is
pressed into the Winding Gear and rides on the hardened surface of the Winding
Spindle. When each winding cycle is completed, the Winding Rack is returned to its
“home” position. In the home position, the rack has a portion of its teeth removed to
disconnect it from the Winding Gear, allowing it to turn backwards as the chronometer
unwinds.
The State-of-wind Potentiometer, coupled to the Winding Spindle by a timing belt,
measures the degree to which the chronometer is currently wound. Complete winding
requires approximately eight turns, so a 10-turn potentiometer is used to follow the
Winding Spindle in a 1:1 ratio. This potentiometer is read by a microcontroller which
controls the winding process.
The bottom end of the Winding Spindle has a 3mm square shaft protruding to allow the
user to apply a manual winding key.
Every hour, the condition of the State-of-wind Potentiometer is measured by the
microcontroller and the Servo Motor is actuated back-and-forth until the chronometer
is fully wound.