Patent ID: 6800045
Filing Date: 2004-10-05
Classification: F16H

Abstract:
A device for transmitting power from a rotary drive source to a driven load and automatically changing gear ratio therebetween in response to resistance at the driven load, comprising an input/output gear set having a central axis and further comprising:an input gear, mounted coaxial with the central axis, the input gear for being driven by the rotary drive source; an output gear, mounted coaxially with the central axis, for driving the driven load; an upper motion transfer gear, mounted coaxial with the central axis and shaft linked to the input gear for rotation therewith; a lower motion transfer gear, mounted coaxial with the central axis and shaft linked to the output gear for rotation therewith; a variance gear, mounted coaxial with the central axis but not linked with either the input or output gear along said central axis, an upper variance determining gear located on a variance determining axis located on the variance gear radially outwardly from the central axis, the upper variance determining gear in mesh with the upper motion transfer gear; a lower variance determining gear located on the variance determining axis and shaft linked thereon to the upper variance gear for rotation with the upper variance determining gear, the lower variance determining gear in mesh with the lower motion transfer gear; wherein during typical operation the input gear shaft drives the upper motion transfer gear, the upper motion transfer gear mesh drives the upper variance determining gear, the upper variance determining gear shaft drives the lower variance determining gear, the lower variance determining gear mesh drives the lower motion transfer gear, and the lower motion transfer gear shaft drives the output gear and thereby drives the driven load; and wherein when resistance to rotation is presented to the output gear by the driven load the lower variance determining gear begins forward planetary motion around the central axis whereby the lower variance gear revolves in mesh around the lower motion transfer gear and thereby begins rotation of the variance gear in the same direction as the output gear, the lower variance gear still rotating the lower motion transfer gear but at a slower speed than in typical operation, to lower the effective gear ratio between the input and output gear such that the output gear rotates slower and with more torque than during typical operation.