DEVICE FOR GRINDING OPHTHALMIC LENSES COMPRISING IMPROVED MEANS OF CLAMPING THE GLASS BLANK FOR GRINDING

摘要

The device comprises a carriage (10), a two-piece shaft (12A, 12B), one piece (12B) of which can be displaced axially for clamping a glass blank (14), and clamping means with a drive (66) and control means for said drive for varying the drive effort thereof and thus the clamping effort as a function of a control variable (F), at least two complementary transmission bodies (28, 74) which can respectively exert an axial force on the mobile piece of the shaft and a reactionary axial force on a support surface fixed to the carriage. The support surface is a stop fixed with relation to the carriage and the control variable (F) is derived from the axial pressure measured by a pressure gauge placed on the fixed stop.