摘要 |
<p>To centre optical lenses for mechanical clamping, especially during bevelling and facetting, a device is used which has a housing (10) in which a split drive shaft (14, 14') with a torque divider (50) is mounted. Two centring spindles (18, 18') in alignment in the axial direction (A) are thereby motor-driven. The spindle ends facing one another carry bell-shaped clamping elements (20, 20') between which a lens (L) can be orientated and clamped. There is an air bearing at least for the lower clamping spindle. Compressed air can be admitted to the air bearing via axially parallel and/or index-ring-shaped passages (90) with control ports (A, B). In particular, pressure can be applied to two diametrically opposite air-cushion zones. The clamping spindle (18) is then axially movable in a free-running manner, in the course of which a diaphragm piston (32) permits infeed proportioned in very fine steps. …<IMAGE>… </p> |