| 摘要 |
A device for transmitting accurate translational and rotary movements includes a rotary input shaft on which is mounted a rotary driving cam which is engaged with a pivotal follower carried on a lever which is pivotally mounted at its one end and has said follower intermediate its length so that the lever is moved backwardly and forwardly. The lever carries a drive roller at its outer end which engages in an annular slot of a disc carried on an output shaft and oscillation of the lever by movement of the cam causes a back and forward axial displacement of the output shaft. Rotary movement is imparted to the output shaft after it first moves through a path in which it is constrained against rotary movement by two roller members which are carried on a fixation piece affixed to the shaft and which are guided on respective sides of an elongated keyway of the housing. The rollers move out of engagement with the keyway after a pinion gear carried on the shaft is moved into meshing engagement with a rack which is carried on a slide which is mounted for movement backwardly and forwardly on one or more guide rods. The slide also carries a follower which is moved by a different cam part and, when it is in meshing engagement with the pinion gear, it produces a controlled rotation of the output shaft. A ribbed barrel cam is employed for effecting accurate rotational movement of the output shaft through the use of two roller followers arranged on respective sides of the ribbed cam and which are preloaded against the cam. The rack is arranged so that it is at a slight angle in respect to the horizontal so that it provides an easy entry of the sliding rotatable pinion gear and meshes therewith without interference after engagement.
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