Dopyera, National & Dobro patents

If you know of any others please let us have the patent nos and we'll look them up.

Note G.D.Beauchamp's name on the single cone patent. His name also appears on several others including the electric frypan.

These patents are listed in order of the date they were granted on. However it is far more informative to observe the date 'filed', which is often 4 or 5 years earlier than the 'granted' date.

If you want to read the full text of these patents, or see higher resolution printable copies, please visit the US Patent Office Site HERE. Use the patent number itself as the item to search for. US patents there are stored in TIFF format, so if your browser does not display the images you will need to install a helper application. There are links to downloadable ones at the US Patent site HERE.

We used the one called AlternaTIFF which worked fine on my PC running IE/Win XP.


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