Schaeffler Group USA Inc. (parent of INA/FAG bearings, a division of Schaeffler Holding, Germany) has been nominated for a 2007 Automotive News PACE Award [website]. PACE is an acronym for Premier Automotive suppliers' Contribution to Excellence. 2007 is the 13th year for the awards, this year sponsored by Microsoft, SAP, and Transportation Research Center Inc.

The nomination recognizes Schaeffler's Tandem Ball Bearings, for use in automotive pinion support applications, paired with ring gear shaft single-row angular contact ball bearings installed in place tapered roller bearings.

Differential cutaway view from top TRBs in blue, Tandem ball bearings in red (courtesy Schaeffler)

Other than a few high-maintenance off-road and racing applications, pinion and differential bearings had become exclusively the realm of tapered roller bearings -- particularly in standard production vehicles and applications.

Schaeffler's Tandem bearing packages, however, are angular contact ball bearings. The Tandem pinion shaft bearings are double-row angular contact ball bearings; the ring gear shaft bearings are single-row angular contact ball bearings.

Schaeffler said testing proves ball bearings in those positions have less sliding friction, higher efficiency, lower NVH (Noise, Vibration and Harshness) levels, while at the same time improving fuel economy and the overall axle assembly performance.

Tandem bearing (courtesy Schaeffler)

Asked by eBearing to describe a tandem bearing, a Schaeffler spokesman describes it as, "a type of double row ball bearing that can take radial loads and axial load in one direction (same as a tapered roller bearing). The rings separate for assembly. Both rows can have different pitch diameters, ball diameters, contact angles, etc. It all depends on application requirements for stiffness, efficiency and life."

The first illustration is a cross-section view looking down from the top of a differential. The standard tapered roller bearings are shown in blue, equivalent Tandem bearing positions in red. This second drawing is a cutaway to better illustrate the varying pitch.

Automotive News PACE Awards, "honor superior innovation, technological advancement and business performance among automotive suppliers." Awards will be announced April 16, 2007 during ceremonies at the Detroit Music Center.