Patent ID: 7707721
Filing Date: 2010-05-04
Classification: F16H,H02K,Y10T

Abstract:
1. A method of manufacturing multiple transmission units having individually selectable gear ratios that vary from unit to unit, said method comprising: providing a multiplicity of interchangeable gear pairs, each gear pair comprising a crown wheel carried on a first shaft and a pinion gear carried on a second shaft, said gear pairs having differing tooth configurations and providing differing gear ratios; providing a housing having therein first and second bearing sections configured respectively to support, within said housing, bearings that are rotably mounted on the first and second shafts of a gear pair selected from said multiplicity of interchangeable gear pairs; selecting, from among said multiplicity of interchangeable gear pairs, a gear pair having a desired transmission ratio; and installing the selected gear pair in the first and second bearing sections in said housing; wherein said first and second bearing sections are configured such that, for every gear pair that may be selected from among said multiplicity of interchangeable gear pairs, said first and second bearing sections support said first and second shafts in such a position and orientation that i) teeth of the pinion gear engage with teeth on a face of said crown wheel, ii) a longitudinal axis of said first shaft is offset by a fixed distance from a longitudinal axis of said second shaft, and iii) said fixed distance is maintained at a constant value which does not vary with or depend on the tooth configuration of the gear pair that is selected; said multiplicity of interchangeable gear pairs includes i) gear pairs with a crown wheel having longitudinally curved tooth flanks and a cylindrical, oblique toothed pinion, and ii) gear pairs in which said crown wheel and said pinion have a spiroplan configuration; said bearing sections are configured to accept gear pairs having gear ratios that vary throughout a range of approximately 1-200, the respective gear pairs in said multiplicity of interchangeable gear pairs are dimensioned and configured such as to permit said selected gear pair to be exchanged for a different gear pair chosen from among said multiplicity of interchangeable gear pairs, for installation in said first and second bearing sections in place of said selected gear pair.