| 摘要 |
PURPOSE:To aim at high accuracy and high speed of leftward and rightward swing of an output shaft by fitting a groove screw gear providing an annular ball track groove, the half circle of which is wound normally and the other half circle is wound reversely, slantly crossing to an input shaft in an axial direction, providing a ball track grove at the circumferential face of a wheel fitted to the output shaft and interposing steel balls therein. CONSTITUTION:An annular ball track groove 4 at the half circle 4a of which is wound normally and the other half circle 4b in an axial direction in a groove screw gear 3 fitted to an input shaft 1. A single ball track groove 6 is provided on the circumferential face of the wheel 5 of an output shaft 2 and steal balls are interposed in the grooves 4, 6. Accordingly, the output shaft 2 is reciprocatively moved in an angle alpha equivalent to the half pitch of the track groove 4 with being rotated by the rotation of the input shaft 1 and the output shaft 2 is swung in the area of the angle alpha. |
