Linear bushings provide extended travel

Edited by the Engineeringtalk editorial team May 11, 2004

THK linear bushings provide machine builders with the opportunity to create extended travel linear motion systems at low cost.

THK linear bushings provide machine builders with the opportunity to create extended travel linear motion systems at low cost.

Perhaps as importantly the product provides low levels of friction and high positional accuracy, making it ideal for a wide range of applications including packaging, materials handling and printing equipment, machine tool equipment and high precision coordinate measuring systems and instrumentation.

Called the LM linear bushing, the product comprises a specially hardened and ground shaft onto which the linear bushing is mounted.

Each linear bushing consists of an outer sleeve, manufactured from hardened and ground steel, and a retainer mechanism within which are a series of between four and six raceways.

These take the form of recirculating tracks, running in the shaft longitudinal direction and each holding a sequence of high precision steel balls to provide effective limitless linear motion.

The overall construction has been designed to reduce the point contact between the shaft and the steel balls to a minimum.

This minimises rolling resistance, thereby eliminating problems associated with friction heat and wear, while enabling the new linear bushing to provide extremely good positional accuracy, with reasonable capacity.

The linear bushing is available in a number of configurations.

These include a standard circular guide, with or without synthetic rubber seals; an open bearing, allowing the shaft to be located by pillars or supporting bases; a version with an adjustable inner diameter; and an extended bearing for use in applications with higher moment loads.

In addition a choice of flanged linear bushings are available.

THK will be supplying the linear bushing as an integrated solution, including shaft, shaft end supports and fittings.

A variety of shaft is available within a degree of precision and accuracy which can be custom machined to order.

Shaft is available in a variety of sizes and material types, such as stainless steel, and can be fully or partially supported if required.