The field of the invention relates to windmills having counterbalancing mechanisms for allowing effective operation under minimal wind velocities.
Windmills have for many years been used for pumping water to supply the needs of rural residents, farmers and communities where surface water is not readily accessible. Their advantages are their simplicity in construction and economical operation.
The disadvantages of commercially available windmills have been their unreliability (due to dependence on a considerable gust of wind to start vane rotation) and the limited depth from which they could pump. The latter problem is particularly serious in areas where the water table is deep or has dropped considerably over a period of years. For these reasons, many users have turned to diesel, gas or electrically powered pumps to provide water for domestic and livestock consumption or irrigation.
In addition to the relatively high initial expenditures for pumps of this type, their cost of operation has increased dramatically over the past few years due to rising energy costs. They are also infeasible in parts of the world where power is unavailable and where the technical expertise for maintaining or operating the pumps is absent.
Attempts have been made to provide a windmill which will be actuated without the need of a sizable gust of wind. U.S. Pat. No. 3,782,222 is an example of a windmill having a counterbalancing system. Other pumping devices, such as disclosed in U.S. Pat. Nos. 1,019,142 and 1,632,322 have also employed counterweights in various manners.