| 摘要 |
<p>The device comprises a smooth cylindrical shaft (52) and a movable body (57) placed on this shaft. The rotation of the shaft (52) causes the longitudinal displacement of the body (57). Balls (50, 51) placed in the body (57) are guided in order to describe a helix (26) on the shaft (52). Two rollers (56, 60) and a ball pusher (65), which elements are integral with the body (57), guide and retain each ball (50) on the shaft (52). Two assemblies, each comprising three balls arranged at 120 DEG about the shaft (52), are situated in two separate planes which are mutually parallel and perpendicular to the axis of the shaft (52). Applications to micro-lithography. <IMAGE></p> |
