- Apr 4, 2006
Perhaps this will make it clearer (or clear as ink). In the photo "W" are wheels and "P" are pinions. W5 and P5 are at the escape wheel. CTR is the center wheel on the minute shaft. The RED line shows the geared path between the center shaft and the escape wheel. If the final ratio of the train of wheels and pinions along the red path is changed, then the escape wheel (W5) will turn more times or fewer times every time CTR (the minute hand) advances 1 turn. Note that W5, the escape wheel is not part of the gear train. The number of teeth on W5 and the length of the pendulum are selected as needed to regulate the speed of the escape wheel so the minute hand rotates exactly once in 60 seconds.so the pendulum lentgh is determined by those 3 wheels plus the escapement? nothing to do with the winding arbor, 2nd 3rd wheels? I could change (theoreticallly) those tooth counts and wouldnt affect the regulation?
The BLUE line (main wheel and 2nd. wheel) is the path where power from the weight enters the system. Notice that the 2nd. wheel and the CTR wheel both mesh with the same 3rd. wheel pinion P3, but the 1st and 2nd wheels are NOT in the train of gears between CTR and W5. Therefore, changing the tooth count on the 1st or 2nd wheel will have NO effect on the timing of the clock. However, altering the 1st and/or 2nd wheels and pinions will change how many times the cord spool will rotate in 24 hours and thus how far the weights are required to drop in 24 hours.