Abstract: A method for grooving or counter-beveling the periphery of an opthamalic lens in a grinding machine is provided. The grinding machine includes a lens support with a mechanism configured to rotate the lens about a first axis, a grooving or counter-beveling wheel rotatable about a second axis which can be tilted relative to the first axis, and a mechanism to adjust the angle of tilt of the second axis relative to the first axis. Initially, a profile for the groove is determined. A single treatment angle corresponding to the profile is calculated, and the angle of tilt of the second axis is adjusted to the value of the single treatment angle. A groove or counter-bevel is ground into the periphery of the lens with the angle of tilt remaining constant throughout the grinding.

Abstract: The apparatus (10) comprises a turret (50), rotatable about a first axis (B-B?), a slide (52) mounted on the turret (50) and a sensor (30) mounted for sliding in the slide (52) along a third axis (C-C?) substantially parallel to the first axis (B-B?). It comprises means (34) for displacement of the sensor for displacing a contact surface (42) of the sensor along the mount (14) during the sensing of the mount. The displacement means (34) comprise means (70) for driving the turret (50) in rotation about the first axis (B-B?). The apparatus comprises control means (82) for controlling means (72) for displacement of the turret in a plane perpendicular to the first axis (B-B?) and suitable for displacing the turret (50) in said plane when the turret is driven in rotation about the first axis (B-B?) during the sensing of the mount.

Abstract: The apparatus (10) comprises a turret (50), rotatable about a first axis (B-B?), a slide (52) mounted on the turret (50) and a sensor (30) mounted for sliding in the slide (52) along a third axis (C-C?) substantially parallel to the first axis (B-B?). It comprises means (34) for displacement of the sensor for displacing a contact surface (42) of the sensor along the mount (14) during the sensing of the mount. The displacement means (34) comprise means (70) for driving the turret (50) in rotation about the first axis (B-B?). The apparatus comprises control means (82) for controlling means (72) for displacement of the turret in a plane perpendicular to the first axis (B-B?) and suitable for displacing the turret (50) in said plane when the turret is driven in rotation about the first axis (B-B?) during the sensing of the mount.

Abstract: The invention relates to a calibration tool (40) for a machine for milling an ophthalmic lens, comprising two lens holder shafts supported on a carriage, and means for moving said shafts. The calibration tool (40) includes a holder (68) mountable on the lens holder shafts, at least one piezoelectric element (92) attached to the holder (68), and at least one sensor member (72) supported on the holder (68) and comprising a sensing area (124) and at least one bearing surface (132, 134) for exerting pressure on the piezoelectric element (92) when the sensing area (124) contacts a surface of the milling machine (2) so that said element generates a contact detection signal. The invention is useful for calibrating milling machines.

Abstract: The invention relates to a machine comprising a train of grinding stones (21), mounted to rotate about a first axis (A–A?), a lens support (15), provided with means (37), for rotating the lens (35) about a second axis (B–B?) parallel to the first axis (A–A?), means (13, 39) for relative radial and axial positioning of the lens support (15) with relation to the train of grinding (21) and a tool carrier unit (17) with a tool (81; 83; 85) fixed to a tool support shaft (75) rotating about a third axis (C–C?). In an active position the tool is adjacent to the second axis (B–B?) and the third axis (C–C?) with a variable angle with relation to the second axis (B–B?). The tool support unit (17) further comprises means (79) for controlling the angle of inclination of the third axis (C–C?) with relation to the second axis (B–B?), when the tool (81, 83, 85) is at a distance from the lens (35). Of application to the grinding of ophthalmic lenses.

Abstract: The method is implemented in a grinding machine comprising a lens support provided with means for driving the lens (15) in rotation about the first axis (A-A?), and a grooving or counter-beveling wheel (51, 53) that is tiltable relative to the first axis (A-A?). The method comprises steps of determining (101) a profile (109) for the groove or the counter-bevel, calculating (103) a single treatment angle (?0) corresponding to said profile (109), adjusting (105) the angle of tilt of the axis (C-C?) of the grooving or counter-beveling wheel (51, 53) to the value of the single treatment angle (?0), and grinding (107) the groove (131) or the counter-bevel in the lens (15) while maintaining the angle of tilt (?0) constant. The invention is applicable to grooving and to counter-beveling lens that present a high degree of curvature.

Abstract: The invention relates to a machine comprising a train of grinding stones (21), mounted to rotate about a first axis (A-A?), a lens support (15), provided with means (37), for rotating the lens (35) about a second axis (B-B?) parallel to the first axis (A-A?), means (13, 39) for relative radial and axial positioning of the lens support (15) with relation to the train of grinding stones (21) and a tool carrier unit (17) with a tool (81; 83; 85) fixed to a tool support shaft (75) rotating about a third axis (C-C?). In an active position the tool is adjacent to the second axis (B-B?) and the third axis (C-C?) with a variable angle with relation to the second axis (B-B?). The tool support unit (17) further comprises means (79) for controlling the angle of inclination of the third axis (C-C?) with relation to the second axis (B-B?), when the tool (81, 83, 85) is at a distance from the lens (35). Of application to the grinding of ophthalmic lenses.