| 摘要 |
<p>The invention relates to a servosystem for driving a shaft in rotation, especially a steering column of a motor vehicle. According to the invention, the servo device (100) comprises an epicyclic reduction train (103) interposed between two shaft portions (104, 106) arranged coaxially and rotating in a stationary housing (101) forming a receptacle for said servo device; the reduction train (103) comprises a satellite carrier (108) fixed to the driving shaft portion (104), a central pinion (111) fixed to the driven shaft portion (106) and a crown (112) mounted loosely on said driven shaft portion; actuating means (116), for example taking the form of electromagnets (117, 119), making it possible to couple the crown (112) selectively either to the stationary housing (101) or to the driven shaft portion (106), in order respectively to provide or to cancel the assistance according to a predetermined criterion. The invention is used for the production of power-assisted steering systems of motor vehicles, with assistance provided when the vehicle speed is below a predetermined low speed. <IMAGE></p> |
