WHEEL DRIVE TRANSMISSION UNIT

摘要

Structural arrangements of wheel drive components facilitate the use of robust main roller bearings that are widely spaced apart from one another. This wide spacing minimizes the torque borne by the bearings for a given external load, because at least one bearing is placed closer to the expected load application point (e.g., the center of gravity of the wheel attached to the wheel hub of the drive unit). The present wheel drive bearings can support a heavy external load without expanding the overall size and configuration of a given wheel drive application.

主权项

1. A wheel drive transmission unit comprising:
a spindle defining a longitudinal spindle axis, said spindle configured to affix to a vehicle frame at an input side of the transmission unit; a hub defining a longitudinal hub axis, said hub rotatable with respect to said spindle about said longitudinal hub axis and configured to affix to a driven wheel at an output side of the transmission unit; a planetary stage functionally interposed between said spindle and said hub, said planetary stage comprising:
an input component positioned and configured to receive power from a vehicle power source;a plurality of planet gears in splined engagement with said input component;a planet gear carrier rotatably attached to each of said plurality of planet gears; anda ring gear in splined engagement with each of said plurality of planet gears, one of said planet gear carrier and said ring gear comprising a output component operably coupled to said hub such that said hub rotates at a rotational speed slower than said input component when said input component receives power; an input-side bearing mounted to an outer wall of said spindle and occupying a first space between said outer wall of said spindle and an inner wall of said hub, such that said input-side bearing rotatably supports said hub; and an output-side bearing mounted to said outer wall of said spindle at a location spaced axially from said input-side bearing by a bearing spacing distance, said output-side bearing occupying a second space between said outer wall of said spindle and an inner wall of said ring gear, said second space larger than said first space whereby said output-side bearing has a larger overall cross-section as compared to said input-side bearing.