Rack and Pinion Drive System
The Item Rack and Pinion drive system offers many unique advantages over conventional bolt-on designs.
The rack itself is designed to sit unobtrusively entirely within the T-slot groove of any Line 8 aluminium extrusion which allows compact linear slides to be constructed without an unsightly bolt-on driving mechanism. No part of the rack projects above the surface of the profile. Additionally, the groove ensures that the rack is aligned parallel to the guide mechanism without unwanted snaking that is often experienced with alternative racks.
Racks of varying length can be built up using any number of individual rack segments. This alone is a very innovative development. Manufacturing in 80mm pieces allows higher degrees of accuracy to be achieved than longer lengths, where pitch errors can be significant, and reduces wastage where much longer racks would have to be cut down to suit the application.
Assembly couldn't be simpler, or quicker. An end section is secured in place with a single dowel screw, and a patented spring clip reliably secures consecutive pieces without the requirement for further machining. Finally, a second end section is fitted and secured in place with a further dowel screw.
The matching 18 tooth pinion is mounted via double ball-bearings in a housing which is neatly secured to the underside of the moving carriage plate. A coupling module is attached to the pinion housing and the pinion's keyed shaft engages with the coupling set contained within. The housing is adjusted to eliminate backlash before being fixed securely in position. The housing is machined according to requirements for the purpose of attaching the drive motor.
The only maintenance required is the application of a few drops of light oil to the pinion housing which contains a pair of felt discs for transferring the lubricant to the pinion.
The rack and pinion drive system is designed for applications with a driving force of up to 1,000N, maximum motor torque of 23Nm and for speeds of up to 3m/s.
Complementing the Item range of belt, ballscrew and chain driven linear slides, the rack and pinion system can be delivered from stock at our Ripley factory, where free design assistance is available from the experienced project engineering team.