Fundamental Studies on Pressurized and Thermal Contraction Microscopic Plastic Gears. lst Report: Principle of Processing and Accuracy.

Abstract

This paper describes the manufacture of microscopic plastic gears by making use of pressurized and thermal contraction. Making a mechanical system microscopic enables the mechanical system to perform more microscopic motion. While it has many merits, the plastic used for gears has several defects. In the experiment, a plastic plate was made film-shaped by the multispindle drawing method. and machined for gear cutting. A high-precision gear is obtained by machining. Then, a microscopic gear is obtained by pressurized and thermal contraction. Since the gear uniformly shrinks in all directions over mutiple shafts, the machining accuracy can be maintained. As a result of the experiment, it has become possible to manufacture gears of 0.05 in module and of 1mm or less in outside diameter. Being high in both tooth profile accuracy and dimensional accuracy, we were able to manufacture gears with the highest accuracy we have seen so far. Since gears with a large face width can be manufactured, widespread applications are foreseen.