Clock Theory - purpose of strike warning

[nan11580]

I have not been able to find an answer to the question "what is the purpose of the warning?" What would happen if there was no warning? When and why did warning begin to be used in striking clocks?

Steven G. Conover's book "Striking Clock Repair Guide" page 42, says that the purpose is that "the "train is 'set' or made ready to begin striking exactly on the hour or half hour . . . the locking of the train is transferred from a slow moving wheel to a faster moving wheel, higher up in the train."

The above explanation does not quite answer my question(s). Bob, I liked the pendulum theory part of your clock videos. Maybe you or someone else can educate me about warning theory, or tell me where to look for an answer. Thank you in advance.

[willofiam]

Good question nan11580 . Studying the theory will be a great advantage in clock repair....Hope this makes sense...For a strike or chime train to function it needs power.... to keep it from running all the time it has to be locked somehow...if it didnt have another lever or function besides the locking then there is really no way to release it to run and then stop it again...at least accurately. That would mean introducing other components so that the locking lever stays out of the way for the proper amount of time...cams, count wheels, racks, ect.... The function of the warning is to advance the strike or chime train a little bit and put one of these other components into play.... keeping the locking lever out of the way until the proper time for it to lock again.....if there is no warning OR very little warning then the locking lever will re-lock the chime or strike train and it wont run....depending on the chime or strike train system will determine how much warning is needed...alot of them are set up with 180 degree warning and others only have a few degrees BUT the concept is the same...enough to advance the train so it wont re-lock....Hope this helps some.

[disciple_dan]

Hello all, I wanted to offer an explanation of this function. Please let me know if I have missed something. Thanks, disciple_dan
As the strike movement sets in its locked state, the time movement continues forward in time. As it advances, the hour cam is lifting the locking levers respectively. When the stop lever is lifted it releases the locking pin and the train begins to move forward, therefore, moving the stop pin ahead of its stop lever. As the pin moves forward a few degrees, it is stopped by the warning lever located deeper in the strike train. As the time train advances further it continues to lift the warning lever and then releases the train allowing it to runs its course. At the end of its run, the appropriate cams drop the stop lever arresting the travel of the stop pin, therefore, locking the train.
If not for this small movement of the stop pin, (warning) when the hour cam releases the stop lever it would (or could) simply drop back down in front of the stop pin and again prevent the strike to occurring.
I hope this is correct and helps some to better understand this function.