| 摘要 |
A twist action roller friction drive comprises a rotatable drive bar 18 which drives roller means about an axis which is inclined relative to the axis of a rotationally fixed, linearly movable driven member 26. The inclined roller means comprises a single annular roller 30,32 urged from the inside into driving contact with the driven member 26 by one or more hydrostatic pads 34. The driven member 26 comprises a tube and the skewed annular roller is in frictional engagement with the bore of the tube. In a typical use, the tube is fixed to the carriage of a machine tool and is aligned with the machine axis. Oil for the hydrostatic pads acting on the roller is supplied through the drive bar along the axis thereof. Axial movement of the driven member is principally determined by the angle of skew of the roller so that if this angle is made very small, similarly small precise movements of the driven member can be achieved. |
