BTW for those who are interested, I may not have done a decent job describing the mechanism, so here goes (some photos below as well) ...
As the clock ticks a few things happen with each tick (it is mechanical)
Two contacts which complete the electromagnet circuit get closer to connecting
A...
I have a related question to all this which someone might be able to point me in the right direction on. I had to unwind one of the coils to repair a break. To the extent that the looped, closed circuit wire isn't effective or serving much of a function (I am suppressing arcing with more...
Empirically, arcing across the contacts which activate the circuit & electromagnets is a definite problem (not to mention some questionable metallurgical choice, which combined are probably one of the reasons this clock maker quickly disappeared), even with this second looped winding.
I have a...
So if I am understanding the emerging consensus here (plus the reference, etc.) it seems like the looped, closed circuit wire may not serve any real purpose, so I could rewind that coil with just the wire connected to the circuit and have a perfectly serviceable electromagnet?
Cheers in advance...
First off, thank you again to everyone for engaging - I suspect this isn't the normal fare for this forum and my ability to describe it accurately is clearly challenged!
Now to a few additional bits of information
- recall this is a old application, circa 1905, early on in low voltage...
Just want to be clear on terminology, I worry I might be confused by what you mean by "2nd coil" above
- there are 2 coils around solid cores
- wired in parallel (though some examples are apparently in series)
- each with 8 windings
- of the 2 different cotton sheathed copper wires
- the larger...
Not sure I can, but I'll give it a go at some point.
In words
- The thicker wire winds up & down the core 8 times and the two ends are connected to the circuit, exiting though 2 separate holes in the bottom
- The thinner wire winds up & down the core 8 times as well, in layers with the wire...
edit: missed the link on the pdf originally!
#159 on page 274 (page 303 in this pdf) perhaps? Discovered by a co-conspirator last night.
The “unconnected” wire does have its two ends connected together.
(Not saying this theory is correct, but presumably this book represents current thinking...
No timing circuit here per se - completely mechanical operation which completes the circuit, causing the electromagnets to fire and "wind" the clock (about once every 2 minutes ... it makes a bit of a racket frankly).
Not sure about the testing, frankly I think they were wining it rather a lot...
FWIW, I’ve been designing (OpenSCAD) & 3D printing replacement parts for this clock ...
Additional detail
- manufactured in 1905 (so no useful part number)
- connected to 3V dry cell battery
- spool has some sort of steel core (a bit rusty these days)
- was connected in parallel with another...
I have a bit of a mystery with a circa 1905 solenoid and not sure where to turn, hoping someone here might have some insight.
The particulars
Circa 1905 solenoid
(application is an electromagnet in a self-winding clock)
8 layers of windings of 2 different cotton sheathed copper wires
paper in...