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US 4,729,261 AGranted
Stepless transmission
OwnerPentti J. Tervolainventor
Life of this patent
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OwnerPentti J. Tervolainventor
Estimating the term…
A stepless transmission including a fixed displacement rotary pump and an adjustable pressure compensated flow control valve which adjustably limits the output of the pump to any selected value between a predetermined maximum and a predetermined minimum whereat the pump housing and the pumping unit therein are locked against relative rotation. In the case of coaxial shafts fixed to the pump housing and pumping unit respectively, the driving shaft drives the driven shaft at the same speed less the speed corresponding to the adjusted limit of the pump even under varying load conditions on the driven shaft. In the case of an epicyclic train having input and output shafts fixed to selected gears of the train, the pump-valve assembly adjustably limits the speed of rotation of another gear of the train, thereby establishing a desired speed of the output shaft under varying load conditions. In addition, a variable speed belt drive between the input shaft and the another gear of the train adjusts the pump-valve assembly responsive to increased load on the output shaft to avoid overloading of the belt drive.
In combination, a fixed displacement rotary pump comprising a housing having inlet and outlet ports, and a pumping unit in said housing operative upon relative rotation of said housing and unit to pump fluid from said inlet port to said outlet port;
In combination, a fixed displacement rotary pump comprising a housing having inlet and output ports, and a pumping unit in said housing operative upon relative rotation of said housing and unit to pump fluid from said inlet port to said outlet port;
In combination, a fixed displacement rotary pump comprising a housing having inlet and outlet ports, and a pumping unit in said housing operative upon relative rotation of said housing and unit to pump fluid from said inlet port to said outlet port;
Dependencies are inferred from the claim text.