Edwards’ design for Foos
Albert Y. Edwards’ 1918 patent for an enclosed, water-cooled engine featured only two main castings, the crankcase and the engine base.
In the early days of gas engine manufacturing, legions of fledgling engineers got their start toiling away at drawing boards tucked away in the poorly lit drawing rooms of established companies like Fairbanks-Morse, IHC and Stover.
Albert Y. Edwards was one of those junior engineers, and he spent at least a few of his early working years crafting engine designs for Foos Engine Co., Springfield, Ohio.
The patent illustrated here, no. 1,257,469, shows Edwards' 1917 design for a horizontal engine. Mechanically, there's nothing particularly novel about Edwards' engine: It's just a simple, horizontal, single-cylinder unit.
What makes Edwards' design interesting is the approach he took for the water hopper and engine castings, as a close inspection shows that Edwards' engine is made from only two main castings; a support base that doubles as a fuel tank and the main crankcase.
In Edwards' design, the crankcase and the water hopper are a single casting, with cooling water surrounding not only the cylinder (as on a standard hopper-cooled engine), but the crankshaft area, as well. Edwards' patent claimed that extending the cooling reservoir rearward to at least partially encompass the crankshaft would result in not only a cooler-running engine, but a stronger and better balanced engine.
In his patent, Edwards claimed his design focused the engine's center of gravity closer to the engine's physical center, concentrating the engine's weight on the engine base, thereby allowing greater engine speeds with less vibration. Evidently not immune to engine aesthetics, he also claimed the design would give "more symmetrical lines" to the engine.
Edwards' patent was awarded on Feb. 26, 1918, to Foos Engine Co., and the design found its way into production in the form of the Foos Type K, which was evidently produced in very small numbers around this time. It's likely it was a manufacturing nightmare, as a casting flaw in, say, a crankshaft bearing saddle would require pitching the entire casting - cylinder, water hopper and all - onto the scrap metal pile. No examples are known to have survived.
Two years after he penned this unique design, Edwards launched the Edwards Motor Co., first in Springfield and later Sandusky, Ohio. Engines produced there featured a centrally located water hopper and a unique, two-piston design yielding a dual rating of 1-1/2 HP and 6 HP, depending on whether it was run on one cylinder or two.
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