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Manufacturers Index - Duplex Rotary Engine Co.

Duplex Rotary Engine Co.
Chicago, IL; Minneapolis, MN, U.S.A.
Manufacturer Class: Steam and Gas Engines

Patents
This page contains information on patents issued to this manufacturer.

Submitting Patent Information

If you find a patent number or patent date by this manufacturer that is not on this list, please contact the Site Historian.


Key to Links for Patent Information

USPTO = U.S. Patent Office . Images of the actual patent can be viewed on the U.S. Patent Office web site but a special TIFF viewer must be installed with your browser in order properly work. More information on how to configure your computer to view these patents can be found at TIFF image Viewers for Patent Images.
DATAMP = Directory of American Tool And Machinery Patents . A sister site to VintageMachinery.org with information on patents related to machinery and tools. A much easier user interface than the USPTO's for finding information on machinery patents.

Patent Number Date Title Name City Description
461,161 Oct. 13, 1891 Rotary Steam Engine Frederick Meyer Englewood, Cook County, IL Application renewed, 16 Mar. 1891.
    Rotary Steam Engine Joseph S. Kiehl Chicago, Cook County, IL  
    Rotary Steam Engine Alexander Grant Riverdale, Cook County, IL  
464,285 Dec. 01, 1891 Rotary Steam Engine Frederick Meyer Chicago, Cook County, IL
905,476 Dec. 01, 1908 Rotary Engine Fredrick Stoehr Minneapolis, Hennepin County, MN
    Rotary Engine Elmer W. Gragert Minneapolis, Hennepin County, MN