The sheer diversity of linear bearing products can be confusing to those who want to use the products in their machine designs. To help clarify things, a report from the Bearing Specialists Association identifies basic machine functions and the linear bearing features each function requires.

Published by the BSA’s Educational Services Committee, “Linear Bearings” uses straightforward, informative charts to look at a number of linear guidance systems, including flat cage assemblies, recirculating roller bearings, recirculating roller systems, recirculating linear ball systems (six, four, and two-row), recirculating ball units, track roller systems, and round shaft systems. It also discusses qualities such as rigidity, accuracy, speed, and friction.

The report can be downloaded for free from the BSA Web site at www.bsahome.org.

SMALL MOTORS EXPERIENCE BIG GROWTH

The North and South American small motor market has seen major growth, with some suppliers having experienced as much as a 40% increase in motor sales in the first quarter of this year, says IMS Research.

IMS Research believes the recent prosperity of the semiconductor end-equipment industry has had the most significant impact on growth rates, especially for stepper motors. Doubledigit growth in medical devices has also boosted small motor sales. While IMS Research expects the growth to continue well into 2005, it cautions manufacturers to be aware that increased outsourcing of OEM facilities and rising raw material prices will have negative effects in the short and long-term.

IMS Research data estimates the North and South American small motor market was worth $1.24 billion last year. The brushed dc motor segment comprises the largest proportion of the market, valued at about $930 million in 2003. But the coreless dc market is projected to experience the greatest growth, with a forecasted market size of $83.7 million in 2008.