Henry Stoltenberg’s 1906 patent for a “Cylinder Cooling Device for Gasolene Engines,” a flywheel-mounted cooling fan. (Photo courtesy of Gas Engine Magazine Archives).
On its face, Henry Stoltenberg's design for an auxiliary cooling fan for stationary engines made perfect sense, especially for a stationary air-cooled engine manufactured specifically, at least initially, to run a washing machine. In practice, it must have been a somewhat fearsome device.
Working for the White Lily Washer Co., Davenport, Iowa, Stoltenberg's 1906 patent, No. 828,867, spelled out the design and construction of a simple cooling scheme, a set of metal fan blades clamped to the rim of an engine's flywheel that, when the engine was running, would effectively push cooling air across the engine's cylinder.
The fan blades were set at an angle and riveted to a large, shouldered band clamp that was wrapped around an engine’s flywheel. The clamp was drawn tight to the flywheel rim with a bolt and nut, and the clamp's shoulders prevented any lateral movement of the fan blade apparatus. Stoltenberg's cooling fan was a signature component of both the White Lily and Schmidt Chilled Gasoline Engines, both manufactured in Davenport, Iowa (and likely in the same factory, given the odd machinations of the two companies, which had a convoluted relationship that included multiple transfers of ownership back and forth).
Presumably, the scheme was motivated by the simple expediency of need, as the air-cooled White Lily engine likely ran hot, especially in the summer in a stationary semi-indoor or weather-protected setting running a washing machine. Early applications of the design left the fan blades completely exposed, but in apparent response to consumer unease with working around the spinning fan blades White Lily (and later – or at the same time – Schmidt Bros. Co. Engine Works) began equipping engines with a simple but sturdy wire mesh guard to prevent possible operator injury.
The concept and execution were laudably simple, but the advent of better options, notably Maytag's simple and reliable air-cooled 2-stroke washing machine engines, saw White Lily and Schmidt both disappear from the market.
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