Parris-Dunn Manufacturing Co.




Founded by William Dunn (1883-1968) in 1917, the Dunn Manufacturing Company began operations in the back of a hardware store in Clarinda, Iowa. William Dunn, a prolific inventor who would ultimately be awarded 49 U.S. patents, began by producing a counterbalance system for Ford’s Model T and a luggage carrier mounted to the running boards of automobiles. In 1925, he was awarded a patent for the automotive “unibody” which Nash was the first to adopt after the patents expired. The majority of automobiles use this method today. In 1928, he designed, built, and licensed a high-wing, three-seat, monoplane which he sold but never produced.

By 1934, his interest turned to wind-driven generators based on his “gyroscopic governor” using the famous “slip the wind” principle. The innovative  governor scheme would tilt the rotor and generator up in high winds to reduce the rotor area from a circular disc to an ellipse with a smaller intake area and thus reduce the power. The rotor and generator could also turned up 90 degrees to the off position by a cable that ran to a crank handle at the base of the tower. In 1936, he joined up with C. L. Parris, a marketing specialist, to form Parris-Dunn Corporation to manufacture wind chargers to power radios and lights on farms and in remote places. They found a ready market for the innovative radio charger design and between 1934 and 1941 shipped 37,000 units to all 48 states and 93 foreign countries. Two small 6 and 12 volt models rated at 135 and 150 watts with a 6 foot diameter two blade propellor direct connected to the generator were offered initially.  Three mid-size 12 and 32 volt models rated at 400 and 650 watts and three larger 32 and 110 volt models rated at 1,000 to 1,250 watts would be added with time. These were all direct-drive, two-blade designs based on the original radio charger design. Two extra large, three-bladed, direct-drive models rated 2,500 to 3,000 watts would be produced in the later years.

During World War II, lagging sales due to the federal rural electrification program were offset by fulfilling their patriotic duty, like so many others, by manufacturing more than 2 million training rifles for the Army and Navy. At its peak, Parris-Dunn had 250 employees and was a great source of local pride. In 1949, Parris-Dunn closed down and the manufacturing plant was acquired by Winpower, formerly the Wind Power Light Co. Winpower continued to manufacture and market the small Parris-Dunn 6 and 12 volt radio chargers increasing the propellor diameter to 7 feet and the raising the power rating to 200 watts. The small gyroscopic radio charger developed by William Dunn would continue to be produced along with the larger Winpower 32 volt wind generators until the late 1950’s.