Video disc reproducer centring and drive - has upper centring disc on drive motor shaft with magnetisable disc in bore for clamping in stabilised position

摘要

A drive system for a video disc reproducer has aerodynamic stabilisation of the disc (1) over a supporting disc (9) under a stabilising disc (3). An upper centering disc (4) is held on the shaft (2) of the drive motor and a magnetisable disc (4a) is seated in a bore (4b) of the centering disc. The disc also has a conical centering face (4c) with a concentric flat face (4d) with regularly distributed radial apertures (4e). The conical surface holds the disc centrally against the upper disc. A lower disc (6) can rotate about and slide along the shaft (5/. It has a flat face (6a) formed of regularly distributed sections (6b) with an elastic central part (7) and a magnetic section (6c) which matches the bore (4b). A lifting device (8) allows the disc to be lifted and centered so that it is clamped between the magnetised faces (4d,6a).