Cycloid gear

Abstract

A housing () with a cylindrical inner housing wall () that is disposed concentrically about a cylinder axis () and is provided with an inner set of teeth (). It further includes an input shaft (), supported rotatably about the cylinder axis (), having at least two eccentric portions () of identical eccentricity () that are disposed rotationally about the longitudinal axis () of the input shaft (). Moreover, it includes an output shaft (), supported rotatably about the cylinder axis (), and the longitudinal axes () of the input shaft () and output shaft () coincide with the cylinder axis (). Furthermore, it includes at least two cycloid disks (), of which each cycloid disk () is disposed rotatably about its own central rotary axis () on an eccentric portion () and has an outer set of teeth (), meshing with the inner set of teeth ()/ The rotary axis () of each cycloid disk () is offset by the eccentricity () to the cylinder axis (), and the diameter of the cycloid disks () is dimensioned such that their outer set of teeth () in one direction comes to mesh with the inner set of teeth (), in which direction the eccentric portion (), on which a cycloid disk () is disposed, is pointing at the moment. Conversely, in the opposite direction, the outer set of teeth () is free of an engagement with the inner set of teeth (), and the cycloid disks () each have reference faces (). Additionally, it includes at least one output device (), supported rotatably about the cylinder axis (), which output device is operatively connected to at least one cycloid disk () such that the motions of one or more cycloid disks (), as they roll in the housing (), are converted into a rotary motion of the output shaft (). The cycloid gear () is distinguished by an even-numbered gear ratio i. The outer sets of teeth () of the cycloid disks () each have an even number of teeth. The inner set of teeth () of the housing () has a number of teeth N+Z or N−Z that is higher or lower than a (whole) number Z.