US Patent: 1,053,940
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Universal motor
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Patent Dates:
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Applied: |
Sep. 09, 1909 |
Granted: |
Feb. 18, 1913 |
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Jeff Joslin Vintage Machinery entry for Independent Pneumatic Tool Co. Vintage Machinery entry for Burke Electric Co. Vintage Machinery entry for Chicago Pneumatic Tool Co.
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Description: |
"This invention relates to electric motors, and more particularly relates to an electric motor which is adapted to be actuated by either single phase alternating currents or direct currents, and to a method of varying the speed and changing the direction of rotation of the motor when supplied with alternating current of the same voltage."A 1919 advertisement for handheld electric drills and grinders from Independent Pneumatic Tool Co. carries the phrase, "Licensed Under Burke Universal Motor Patent". A condensed catalog for Duntley (a brand for Chicago Pneumatic Tool Co.) shows their "Universal Electric Drills". "This type of tool is fully covered by letters patent granted February 18, 1913." |
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