US Patent 8186887 Double row tapered roller bearing unit

Both outer-side inner ring elements 14 apply preload to respective tapered rollers 16 by being pressed from both sides in an axial direction by an outwardly-directed, flange-like collar 30, formed on an outer circumferential surface of one end among both ends in the axial direction of an inner-side outer ring member 22, and by a holding ring 31, mounted on the other end of the inner-side outer ring member 22, or by a pair of holding rings 31, mounted on both ends in the axial direction of the inner-side outer ring member 22. A double row tapered roller bearing unit having good assembly precision, being easy to process, and enabling preload control and preload readjustment to be performed with ease is thereby provided.