Abstract
Recently, low noise gears without lubrication are required for business machines and robots, because they
are used in open space. The present article provides a new type gear consisting of steel and resin (called
Delrin-100), which has good lubrication characteristics. Our gear has profile shifted steel gear teeth.
Delrin-100 resin is inserted in a grove, which is cut around the gear teeth of the steel gear so as to have
strong gear teeth. Hence, the tooth made of Delrin resin is supported at both sides. This means that only
resin gear tooth contacts to the follower gear tooth, but steel gear tooth does not contact. Production
processes are presented for the gear, and its characteristics are investigated. It is ascertained that the
strength of our gear is greater than that of a plastic gear, and noise of our gear is small in comparison with
plastic gears. The design method is presented, and effects of frictions on the position control are also
investigated.
