Mechanism for transforming rotational into linear motion.

摘要

A motion transforming mechanism comprises a rotation shaft (11) having a center axis (CA11) and formed with at least three cranked shaft portions (11a, 11b and 11c) having respective eccentric axes (CA11a, CA11b and CA11c) in parallel relationship to one another and to the center axis (CA11), the eccentric axes of the cranked shaft portions (11a, 11b and 11c) being displaced from and arranged equiangularly around the center axis (CA11). The motion transforming mechanism further comprises a plate assembly (12) constituted by at least three rotation plates (13 to 15) having a plurality of teeth (13b, 14b and 15b) and formed with cranked through bores (13c, 14c and 15c), respectively. The cranked shaft portions (11a, 11b and 11) of the rotation shaft (11) are rotatably received in the cranked through bores (13c, 14c and 15c) of the rotation plates (13 to 15), respectively. The motion transforming mechanism further comprises an annular toothed rail (19) having a mid-circumferential plane (MP) perpendicularly intersected by the center axis (CA11) of the rotation shaft (11) and having an inner surface configured to have a plurality of teeth (19b) held in mesh with the teeth (13b, 14b and 15b) of the rotation plates (13, 14 and 15). The rotational motion of the rotation shaft (11) causes each of the rotation plates (13 to 15) to be rotated with respect to the center axis (CA11) of the rotation shaft (11) and being transformed into a relative curvilinear motion between the annular toothed rail (19) and the plate assembly (12).