Bullwheel

A bullwheel is a large wheel on which a rope turns, such as in a chairlift. In that application, the bullwheel that is attached to the is called the drive bullwheel, with the other known as the return bullwheel.

Originally, bullwheel was an oil field term applied to the large wheel that turns the drum upon which the drilling line is wound in percussion drilling.

The bullwheel (or bull wheel) began use in farm implements with the reaper. The term was commonly used to describe the traveling wheel, traction wheel, drive wheel, or harvester wheel. The bullwheel powered all the moving parts of these farm machines including the reciprocating knives, reel, rake, and self binder. The bull wheel's outer surface provided traction against the ground and turned when the draft animals or tractor pulled the implement forward.Cyrus McCormick used the bullwheel to power his 1834 reaper and until the early 1920s when small internal combustion engine gasoline engines like the Cushman Motor began to be favored.

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