Challenges of Miniaturizing a Precision Gear

Abstract

Miniaturization offers two options to come closer to the micro and nano scale: bottom-up or top-down. Each method has its own and unique benefits, although in practice the top down approach is more common, as most companies find the top down approach to be the simpler method. So can similar processes use the top-down method to reduce the size of a precision gear? In our first attempt, a plant gear similar to a harmonic drive gearbox is to be made it smaller, lighter and cheaper using a 3D printing method. Then industry 4.0 lab is used to see how the production process meets I 4.0 requirements. Working on RP4 gears, which have been patented by TU Vienna, nearly no backlash can be expected due to the use of radial ball bearings. If the RP4 gear is miniaturized to one tenth of the original size, functionality issues can be expected because of the smaller auxiliary parts, and no matching radial ball bearings are available in the official market. Thus, our focus is on redesigning the existing gear which will have the same functionality. Furthermore, the geometric tolerances of the existing are compared with the new gears produced by additive manufacturing to understand the functional and metrological problems. Possible solutions may lie in modifying those bearings or in creating a new generative design instead.