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Actually really heavy motors transformers etc use square most of the time and the lead from the buss may be ribbons stacked to give the flexibility a heavy bar doesn't have. All I was saying (I love your thread and don't wish to hijack it) was that the reasoning behind using ribbon in a vc and using it in a rheostat are different so while one may have come from the other, it may not have. I guess if ribbon wire was already a commodity there may not even be a patent for using it in a vc, but I'd sure like to know who's idea it was and if the original reason was the reason that they have sold all these years.
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Found it! The patent specifically for edgewound voice coils in loudspeakers, not only for flat wire, but triangular wire as well;
OSCILLATING COIL FOR ELECTRODYNAMIC LOUDSPEAKERS
Patent number: 1935404
Filing date: Feb 19, 1932
Issue date: Nov 1933
Inventor: Joachim Leopold
Assignee: Telefunken Gesellschaft fur Drahtlose Telegraphic
Only a few months later, Wente refers to the use of an edgewound voice coil in a familiar Bell patent;
ACOUSTIC DEVICE
Patent number: 1930915
Filing date: Jul 13, 1932
Issue date: Oct 1933
Inventor: Edward C. Wente
Assignee: Bell Laboratories
Hmmmmm...:hmm:
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I'm impressed. I don't even have time to completely read what you've found. Let alone, research it. I wonder if anyone produced any speakers with no bobbin. I bet someone has patented hex wire at some point as it would allow the most conductor in a multilayer. I've got to go to the start of this thread and try to follow your step by step.
How do I mark a thread so I don't have to search for it when I want it?
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This patent is for the Altec Acousta-Voicing Process. Specific embodiment as yet undetermined, could span several product models of equalizers and related items.
SOUND-IMPROVING MEANS AND METHOD
Patent number: 3624298
Filing date: Mar 5, 1969
Issue date: May 1972
Inventors: Arthur C Davis, Donald B Davis, Tustin; James J Noble
Assignee: LTV Ling Altec
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There have been voice coils without supporting bobbins. L.G. Bostwick's 596A tweeter used an unsupported edgewound aluminum coil which was glued directly to the aluminum diaphragm. Smith and Selsted used (I think) a two layer round wire aluminum voice coil similarly glued to an aluminum diaphragm. In both these instances the goal was to minimize mass to extend the high frequency response.
The Western Electric 555W compression driver used an edgewound aluminum voice coil, and was in large scale production by 1926 or 1927. I believe this was the first use of a ribbon wire voice coil in a loudspeaker. The U.S. Patents #1,707,544 (A.L. Thuras) and 1,707,545 (E.C. Wente) describe the driver in detail. The particulars of the voice coil design and construction are discussed in depth in Mr. Thuras' patent.