Re: [time-nuts] The pendulum problem...
Mike- Yes, I was wrong. The idea of constant driving power was around. Sadly most of these early American tall clocks with often sand filled weights used a simple design since as you noted cost was important and raw metals such as brass was hard to produce locally and often imported from Europe. I think the best I can do is to use the basic design from the article that David noted and will have to adjust the clock once a week after winding. -Brian, WA1ZMS/4 iPhone On Jan 31, 2014, at 4:33 AM, mike cook michael.c...@sfr.fr wrote: Le 31 janv. 2014 à 06:06, Brian, WA1ZMS a écrit : snip Modern pendulum clocks have a modified gear drive where the escapement is still being driven while the main wheel is being advanced to wind the weight cable. Not the case for 200+ year old clocks. It is not so much the case that it wasn't available as not always implemented . The problem, and its solution maintaining power had been addressed by many since Christian Huygens in the 17th C. and also John Harrison , the inventor if the marine chronometer in the mid 18th C. Similarly the principle exists for spring wound clocks, but is often omitted to keep the price down. Regards, -Brian, WA1ZMS/4 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Le 31 janv. 2014 à 06:06, Brian, WA1ZMS a écrit : snip Modern pendulum clocks have a modified gear drive where the escapement is still being driven while the main wheel is being advanced to wind the weight cable. Not the case for 200+ year old clocks. It is not so much the case that it wasn't available as not always implemented . The problem, and its solution maintaining power had been addressed by many since Christian Huygens in the 17th C. and also John Harrison , the inventor if the marine chronometer in the mid 18th C. Similarly the principle exists for spring wound clocks, but is often omitted to keep the price down. Regards, -Brian, WA1ZMS/4 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Brian, It would seem that while you are winding the clock, the pendulum could be measured by the use of the same coil that syncs it. That way you would sense the run down and over a short period after the clocks been wound speed up to re-align the tick. I could imagine a coil below the pendulum and perhaps every other second it senses the pendulum and the next second it pulse the pendulum to realign and power the clock. If you feed energy to the pendulum why do you need weights? (May have just gotten into trouble here). Regards Paul WB8TSL On Fri, Jan 31, 2014 at 7:23 AM, Brian, WA1ZMS wa1...@att.net wrote: Mike- Yes, I was wrong. The idea of constant driving power was around. Sadly most of these early American tall clocks with often sand filled weights used a simple design since as you noted cost was important and raw metals such as brass was hard to produce locally and often imported from Europe. I think the best I can do is to use the basic design from the article that David noted and will have to adjust the clock once a week after winding. -Brian, WA1ZMS/4 iPhone On Jan 31, 2014, at 4:33 AM, mike cook michael.c...@sfr.fr wrote: Le 31 janv. 2014 à 06:06, Brian, WA1ZMS a écrit : snip Modern pendulum clocks have a modified gear drive where the escapement is still being driven while the main wheel is being advanced to wind the weight cable. Not the case for 200+ year old clocks. It is not so much the case that it wasn't available as not always implemented . The problem, and its solution maintaining power had been addressed by many since Christian Huygens in the 17th C. and also John Harrison , the inventor if the marine chronometer in the mid 18th C. Similarly the principle exists for spring wound clocks, but is often omitted to keep the price down. Regards, -Brian, WA1ZMS/4 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
wa1...@att.net said: I think the best I can do is to use the basic design from the article that David noted and will have to adjust the clock once a week after winding. How far off does it drift while you are winding? I haven't wound a pendulum clock since watching my grandfather (and maybe helping) when I was a small child. I think it was basically lift the weight with one hand and pull down gently on the other end of the chain with the other hand. I assume there was ratchet in there. Is that the way your clock works? Can you wind it a little bit while the pendulum is swinging and then let go so the weight does its thing when the pendulum gets to the end? Repeat ... -- I assume you are familiar with the Scientific American article from many years ago. They put a magnet on the pendulum and used that to kick the pendulum at the right time. As well as keeping good time, it also supplied power so you didn't have to wind it. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
The escapement wheel needs to have a little torque on it so it will turn as the pendulum swings. Regards. Max. K 4 O DS. Email: m...@maxsmusicplace.com Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Woodworking site http://www.angelfire.com/electronic/funwithtubes/Woodworking/wwindex.html Music site: http://www.maxsmusicplace.com To subscribe to the fun with transistors group send an email to. funwithtransistors-subscr...@yahoogroups.com To subscribe to the fun with tubes group send an email to, funwithtubes-subscr...@yahoogroups.com To subscribe to the fun with wood group send a blank email to funwithwood-subscr...@yahoogroups.com - Original Message - From: Hal Murray hmur...@megapathdsl.net To: Discussion of precise time and frequency measurement time-nuts@febo.com Cc: hmur...@megapathdsl.net Sent: Friday, January 31, 2014 12:49 PM Subject: Re: [time-nuts] The pendulum problem... wa1...@att.net said: I think the best I can do is to use the basic design from the article that David noted and will have to adjust the clock once a week after winding. How far off does it drift while you are winding? I haven't wound a pendulum clock since watching my grandfather (and maybe helping) when I was a small child. I think it was basically lift the weight with one hand and pull down gently on the other end of the chain with the other hand. I assume there was ratchet in there. Is that the way your clock works? Can you wind it a little bit while the pendulum is swinging and then let go so the weight does its thing when the pendulum gets to the end? Repeat ... -- I assume you are familiar with the Scientific American article from many years ago. They put a magnet on the pendulum and used that to kick the pendulum at the right time. As well as keeping good time, it also supplied power so you didn't have to wind it. -- These are my opinions. I hate spam. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] The pendulum problem...
Not know much about the clock in question... ...how about replacing the weight and cable with an endless cable and motor to constantly 'pull' on the thing... You might have to remove a few parts, but may be able to make the changes so you can always restore the clock to original condition later. ...maybe put the motor on a spring pivot mount, and 'wind' the spring mount between two sepoints. (If you can even follow what I mean! :) ) Dan On 1/31/2014 3:28 AM, time-nuts-requ...@febo.com wrote: Has anyone addressed the issue of trying to keep a pendulum clock locked to an external reference (i.e.: via electro-magnet, etc.) and yet can work around the problem that very old pendulum clocks have an issue with the escapement drive stopping while such a typical 8-day antique clock is being wound? ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Thanks for all the ideas and replies. Let me see if I can address all points in just one e-mail. 1) The clock(s) in question are very costly and to modify them in any way would instantly kill the value. These are part of history collection in 100% original condition. 2) These clocks wind with a crank handle and winding rolls the cable back onto the main-wheel drum. (Chain drive clocks were a ~100 year later design in America) 3) The pendulum is 1 meter long and takes a full second to travel from one end to the other. So 1PPS or 0.5PPS synching is easy to do with a magnet, etc... 4) The escapement is of the anchor type, and as such when you wind the running weight you are driving the main wheel backwards. Such an escapement will run backwards during the winding and so I lose about 20 seconds or so during the winding. The speed of the wind also can allow for a typical forward second to happen between the clicks on the drum. Sometimes I get a loss of 15 seconds, sometimes 20, etc... 5) The pendulum is still swinging during the wind. It's a 1kg weight on a 1m rod. Takes lots of energy to stop it. 6) The escapement shaft comes through the front dial to a small second hand and so you can see the second hand either pause, run forward, run backwards during a wind. I am concluding that without a fancy way to wind such a clock, it will only be locked to an external source during a typical 7-day run. I'm asking for a solution to a problem that exists only as a want, not a need. Nevertheless, it is still very satisfying to hear the tick of such an old clock as the trigger LEDs on a 5370B blink at the same rate. It was TVB that pointed out to me the idea of just how many of our Rb's, Cs's, and OCXOs will still be running 200 years from now. That thought still gives me pause. -Brian, WA1ZMS ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Hi: The Zendulum uses a magnetic ball as the pendulum (it rides on a curved track rather that from a string like the first version) and there's a coil in the base. Each pass over the coil causes the coil to output a pulse that drives a circuit that in turn sends a power pulse to the coil repelling the magnet. I would think this same circuit (maybe a higher power version) could be used to keep a pendulum going. If so the drive train could be removed. BUT . . . the quality of the time keeping is determined by the pendulum, this is just how it's powered. http://www.prc68.com/I/GeekStuff.html#Zendulum If you want to retain the existing drive system then I like Paul's idea. i.e. a micro controller, coil and small magnet so that you could speed up or slow down the pendulum to bring it back into phase after winding quickly. The DS3231 is a fairly accurate real time clock that could be used to discipline the pendulum. Have Fun, Brooke Clarke http://www.PRC68.com http://www.end2partygovernment.com/2012Issues.html paul swed wrote: Brian, It would seem that while you are winding the clock, the pendulum could be measured by the use of the same coil that syncs it. That way you would sense the run down and over a short period after the clocks been wound speed up to re-align the tick. I could imagine a coil below the pendulum and perhaps every other second it senses the pendulum and the next second it pulse the pendulum to realign and power the clock. If you feed energy to the pendulum why do you need weights? (May have just gotten into trouble here). Regards Paul WB8TSL On Fri, Jan 31, 2014 at 7:23 AM, Brian, WA1ZMS wa1...@att.net wrote: Mike- Yes, I was wrong. The idea of constant driving power was around. Sadly most of these early American tall clocks with often sand filled weights used a simple design since as you noted cost was important and raw metals such as brass was hard to produce locally and often imported from Europe. I think the best I can do is to use the basic design from the article that David noted and will have to adjust the clock once a week after winding. -Brian, WA1ZMS/4 iPhone On Jan 31, 2014, at 4:33 AM, mike cook michael.c...@sfr.fr wrote: Le 31 janv. 2014 à 06:06, Brian, WA1ZMS a écrit : snip Modern pendulum clocks have a modified gear drive where the escapement is still being driven while the main wheel is being advanced to wind the weight cable. Not the case for 200+ year old clocks. It is not so much the case that it wasn't available as not always implemented . The problem, and its solution maintaining power had been addressed by many since Christian Huygens in the 17th C. and also John Harrison , the inventor if the marine chronometer in the mid 18th C. Similarly the principle exists for spring wound clocks, but is often omitted to keep the price down. Regards, -Brian, WA1ZMS/4 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Count the period where the counterweight is disconnected from the movement using a microswitch and then program the controller to speed up the clock to make up the difference until the next time the clock needs to be rewound. Sort of like the way my bank just recalculated my escrow fund:-) -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida jleik...@leikhim.com 407-982-0446 WWW.LEIKHIM.COM ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] The pendulum problem...
Joe- You might be on to a good idea. If I could use a pair of optical sensors to watch the escapement wheel when winding, then I could count any movement in either direction or no movement at all and know how much to slew the timing pulses say over the next hour or two to get the clock back on time. The nice thing is I can clip the opto sensors and remove them just as quickly with no change to the mechanism itself. Again...what a great bunch the Time Nut crowd is! -Brian, WA1ZMS/4 iPhone On Jan 31, 2014, at 4:00 PM, Joe Leikhim jleik...@leikhim.com wrote: Count the period where the counterweight is disconnected from the movement using a microswitch and then program the controller to speed up the clock to make up the difference until the next time the clock needs to be rewound. Sort of like the way my bank just recalculated my escrow fund:-) -- Joe Leikhim Leikhim and Associates Communications Consultants Oviedo, Florida jleik...@leikhim.com 407-982-0446 WWW.LEIKHIM.COM ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] The pendulum problem...
Now that I have exposed myself as being an antique time-nut as well as a modern one, (I'm a man of extremes!) I have a question to the group.. Has anyone addressed the issue of trying to keep a pendulum clock locked to an external reference (i.e.: via electro-magnet, etc.) and yet can work around the problem that very old pendulum clocks have an issue with the escapement drive stopping while such a typical 8-day antique clock is being wound? I can understand and deal with syncing the pendulum to an external reference.. but you end up with a time offset when the clock's main wheel is being wound once a week. The pendulum does keep swinging however the drive power to the 2nd gear is being removed while the clock is being wound. Modern pendulum clocks have a modified gear drive where the escapement is still being driven while the main wheel is being advanced to wind the weight cable. Not the case for 200+ year old clocks. Regards, -Brian, WA1ZMS/4 ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
