Development of High Response Linear Motor which Reduced Magnet Volume

Abstract

In applications such as semiconductor and liquid crystal substrate processing, a linear motor drive is widely used because of its high response and high acceleration rate. A linear motor using rare earth magnets with iron cores is used for realizing large thrust and for downsizing. Recently, the material cost for rare earth magnets has increased sharply. In order to realize a higher acceleration rate and to reduce the magnet mass, we have developed a novel linear motor, in which the stator consists of several armature cores, and a single winding wound around the plurality armature cores commonly. We call this motor a “phase concentrated winding linear motor”. Owing to its unique structure, it has various advantages such as reduced flux leakage and improved productivity. In this paper, the new structure and the advantages of the phase concentrated winding linear motor are discussed. We also show the experimental results obtained with its prototype, such as an acceleration rate of approximately 70G in high acceleration driving.