IN THE NEWS
Linear Drive Systems Enabling Precision Parts Production
Featured in the September issue of Motion System Design
Differences abound between traditional rack and pinion twin drives, split-pinion-based designs, and roller-pinion systems.
From aerospace to machine tooling, glass cutting, medical and more, manufacturing processes depend on reliable motion control. Delivering the speed and precision required by these applications are various servo-controlled linear drive systems.
One common setup combines servo controls with a traditional involute rack and pinion. The latter can require clearance between rack and gear teeth to prevent jams and excessive wear, or else environmental changes (such as a 10° temperature shift) can lock up the system as gear teeth expand. On the other hand, clearance results in backlash, which is equivalent to error.
Linear Actuators Achieve Precision Motion Control With Little to No Backlash
Featured in the June issue of Machine Design
Roller-pinion systems are a better option than rack and pinions where accuracy and a minimum of friction are important. Consider a traditional rack-and-pinion system. It consists of a toothed circular pinion that engages the teeth on a flat rail, converting rotary to linear motion. Now consider what’s called a roller-pinion system. It still has the pinion/rack combination, but the teeth on the pinion are replaced with bearing-supported rollers that engage a unique tooth profile. Each tooth is precisely measured relative to the first, eradicating cumulative error and maintaining high positional accuracy. The result is accurate positioning up to ±30 µm (±0.00118 in.) — within half the diameter of a human hair — at speeds up to 11 m/sec (36.1 fps).Learn more