Thomas Edison
Thomas Edison at his Iron Mine, Ogden, New Jersey, 1895
We all know Thomas Edison as one of the greatest inventors of all time including the electric light bulb and all other components of electrical generation and distrbution. All of Edison’s electical inventions were bundled to develop the industry under the company nme “Edison General Electric Company” of which Edison was well placed. But Edison was generally considered a poor businessman and did not get along with his business associates. So in 1892, he sold all his interest for approximately $2 million and the Edison name was removed as we know it today as “General Electric”.
Edison returned to a previous venture in iron ore processing. Having high hopes for what he could achieve Edison said: "I'm going to do something now so different and so much bigger than anything I've ever done before people will forget that my name ever was connected with anything electrical." His New Jersey mining operation (Ogden, NJ) was built to address an iron ore shortage. His business strategy was developed around his new rock-crushing technology and an electromagnetic ore separator to extract low-grade ore from crushed boulders. The final product -- a briquette made of powdered iron ore. Completed in 1889, the building was one of the world's largest ore-crushing mills in the world at the time and contained three giant electromagnets intended to process up to 1200 tons of iron ore every day. He signed a 3 year contract to supply Bethlehem Steel in nearby Pennsylvania. But soon after Edison started his operation, high grade ore was discovered around Lake Superior and his product didn't do well commercially. In 1899, Edison closed his mine and left the industry having lost all of the $2 million from General Electric. Edison commented about the financial losses, "it's all gone, but we had a hell of a good time spending it."
But Edison realized the potential application of his technologies to the cement industry and formed the Edison Portland Cement Company that same year.
A Belt Conveyor Pioneer
Thomas Edison’s low grade iron ore mine in New Jersey where he developed his rock-crushing and electromagnetic ore separator operation required the processing of large volumes of rock to supply his contract. As with many of Edison’s ventures, there were no known methods to move and handle such high volumes which required more innovations. One area was the need for better belt conveyors. Prior, belt conveyors were mostly (if not only) used in grain handling and consisted of flat canvas belts on single flat idler rolls with full length skirting. Since this configuration could not carry the required tonnage, troughed idler roll configurations and rubber covered belts (see Thomas Robins Jr Blog) as well many other things were developed.
Most of us familiar with the differences in conveying grain vs. iron ore would easily see the problems Edison and Robins faced. A patent search from this period will find many patents assigned to Thomas Edison including two for transfer chutes. Obviously they were not as successful as some inventions as transfer hutes are still problematic.
