“How much do you trust your linear bearing technology?” That is the type of question PBC Linear asks design engineers on multiple different projects demanding reliable performance, long product life, and simple integration. On a bed-of-nails lift table application, the question becomes more to the point. For linear ball-bearings, any slight contamination of the bearing cages can lead to breakage, stalling or total machine failure; which results in a low rate of confidence when lying on a spiky table. CW Shaw Inc, a designer and fabrication firm that specializes in bringing interactive, fun and educational museum exhibits to life was posed with this problem. After considering the design, load, environment and necessary long-term operation, CW Shaw opted for Simplicity pillow block housings to guide the support rails on the bed-of-nails lift table.
To demonstrate the full effect of the exhibit, the lift table needed to be raised/lowered by 3", handle loads up to 1000 lbs (for safety) and move at a moderate speed of 5 ft/minute. Potential contamination was also a factor CW Shaw considered. Any trace of dust or particulate posed a risk of system failure; raising safety concerns. Therefore, CW Shaw sought a linear motion system that would not fail under contamination (dust and carpet fibers). Since most museums operate on fixed budgets, CW Shaw also held maintenance-free operation as a crucial design pre-requisite; which is why he turned to Simplicity linear plane bearings and pillow block assemblies.
Simplicity products are a proven solution when requiring maintenance-free, worry-free linear motion. Designed and refined for over 25 years, Simplicity technology has been successfully applied in some fo the most extreme environments: temperature extremes, high contamination and shock vibration. The bearings travel using a proprietary Frelon liner which transfers the load and glides over dust and other particulate without damaging the shaft. Also, since they are composed of no rolling elements, Simplicity pillow block housings will NOT catastrophically fail; allowing for reliable and safe linear guidance of the support rails.
Two Simplicity pillow block assemblies were installed at each end of the lift table to support load and guide the lift rails. CW Shaw noted no problems in performance and, over time, has implemented the design for several nail bed exhibits throughout the country—some of which have been running without fail for 5-10 years.