| 摘要 |
A linear actuator of the threaded shaft actuator type comprising a rotary threaded shaft and a special bearing unit secured to the member to be moved linearly, in which the bearing unit comprises a plurality of rollers each having a plurality of radial right flanges intermediate their ends spaced apart and scheduled to complement the pitch of the shaft threading for rolling engagement herewith, which rollers at their ends are formed with bearing surfaces that are oblique relative to their axes that ride on spaced apart raceways defined by an outer race structure which in turn is secured to the member to be moved linearly. When shock loads are to be resisted, the bearing unit includes a nut threaded on the shaft and formed to receive the rollers without journaling same and be rotated by the rollers, and the bearing unit is resiliently mounted for cooperation with a stop fixed relative to the member (that is to be moved linearly) from which the nut is normally spaced, such that the nut normally serves no load bearing or transmitting functions, but when shock loads are occasioned, the nut engages the stop to transmit the shock loads thereto in bypassing relation to the rollers and the surfaces they cooperate with. |
