The Timken Company

Ronald P Dickerhoff

Gary E Kreider

Harold E Hill

An aluminum transmission or transaxle case contains a steel shaft which is supported in the case on two directly mounted tapered roller bearings, so that the two bearings confine the shaft both radially and axially. To compensate for the differences in expansion and contraction between the aluminum case and the steel shaft as the transmission or transaxle experiences variations in temperature, a race of at least one of the bearings is fitted with a compensating ring having a coefficient of thermal expansion greater than that of the case or shaft. As a consequence, the bearings operate at a generally uniform setting over a wide range of temperature variations.

Machine with thermally compensated bearings

A roller-type rock bit has a body which fits into a drill hole and is provided with inwardly directed spindles about which cone-shaped cutters revolve. Between each spindle and its cutter is a tapered roller bearing, a flat thrust bearing, and a sleeve-type radial bearing arranged in that order from the large end of the cutter. The raceways of the tapered roller bearing converge toward the small end of the cutter, and that bearing is unitized by a thrust rib located on the spindle opposite the small ends of the rollers and a rib ring which fits into the cutter opposite the large diameter ends of the rollers. Thus, a major portion of the radial load encountered in drilling is taken by the tapered roller bearing, as well as a significant portion of the thrust load, with both of those loads being transferred between the raceways generally transversely through the tapered rollers. Any thrust loading in the opposite direction is transferred between the rib ring and the thrust rib generally axially through the rollers. The rib ring further closes the end of the cutter and, together with a stream of air that flushes the interior of the cutter, prevents rock cuttings from entering the cutter and damaging the bearings.

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Louisville, OH, United States of America

Ronald P Dickerhoff