Abstract: A machine for grinding opthalmic glasses including a carriage, a clamping shaft carried by the carriage and composed of two shaft parts for clamping therebetween an opthalmic glass blank, and a clamp cooperative with at least one of the shaft parts for exerting an axial force thereon. The clamp includes a motor-speed reducer unit having a motor, transmission elements for transmitting the driving force of the motor to at least one of the shaft parts, a housing enclosing the motor and the transmission elements and mounted relative to the carriage to pivot about a pivot axis, a reaction spring connecting the housing to the carriage, and a control unit associated with the motor and with the spring for varying the driving force of the motor as a function of the variation in the length of the spring.

Abstract: Machine for grinding and bevelling ophthalmic lenses of the type comprising a carriage movable in translation and in oscillation in directions parallel to and perpendicular to a shaft carrying grinding wheels for edge trimming (4) and bevelling, and a follower (7) for measuring the distance between the plane tangent to the pole of the convex surface of the lens and the edge of the surface and for measuring the value which corresponds to the width of the edge surface (12) of the lens (3). The follower (7) has a surface (8) having a convex curvature identical to that of the grinding wheel and which comprises a matrix of detection elements which cooperate with the edge surface (12) of the lens. Each of the detection elements is connected to a corresponding portion of a sensor (14) to which it transmits a signal representing the passage of a part of the edge surface (12) of the lens in front of the corresponding detection element.

Abstract: The apparatus comprises a device which explores without contact the inner contour of the frame rim (16) and employs an optical device (30) for sensing the image of characteristic points of the rim inner contour, an analyzer for analyzing the sensed images for determining the spatial coordinates of the characteristic points, and a calculating device for reconstituting the shape and/or the profile of the contour of the frame rim from these spatial coordinates.

Abstract: Device for mounting an adapter (18) on a lens blank (12), in particular for a lens centering machine (10). The device is of the type comprising a housing (22) in which is slidably mounted a mounting shaft (24) having an end (26) which is adapted to receive the adapter (18). The housing (22) is mounted to be movable between a position for loading the adapter (18) at the end (26) of the slidable shaft (24) and a position for mounting the adapter (18) in which the slidable shaft (24) extends in a direction (X--X) perpendicular to a support surface (P) for the lens blank (12). The device further comprises a frame (11) on which the housing (22) is mounted to be pivotable about a first pivot pin (34,Z--Z) parallel to the support surface (P) between the adapter-loading position and the adapter-mounting position, and an arrangement (50,64,72) for consecutively actuating the pivoting of the housing (22) and the sliding of the slidable shaft (24).

Abstract: In a method employed by the device, the distance between a shaft (14) of a grinding wheel (13) and a shaft (5) carrying a finished glass (7) in contact with the grinding wheel, is measured by means of a microprocessor (18) controlling a shifting device (11), by bringing a tracer member (9) in contact with a template (8) mounted on the shaft (5), a standard disk (20) being mounted on the shaft (14) coaxial with the grinding wheel (13) for measuring the distance between the shaft (14) and the shaft (5) by bringing the standard disk in contact with the finished glass.

Abstract: A machining and bevelling tool, which is adaptable to a standard grinding machine for ophthalmic glasses, includes a metal body (1) having in its periphery a V shaped groove (2) and at least two teeth (3) each in the form of a small inserted plate (4) presenting a notch of corresponding V shape which protrudes in said groove (2), a shallow adjacent recess (8) being provided in front of each tooth (3), considering the direction of rotation of the tool. The diameter of the tool is larger than that of an ophthalmic glass, and substantially equal to that of a standard grinding wheel for ophthalmic glasses.

Abstract: The device comprises a grille (9) by multiple slats (11) which are inclined in the manner of slats of Venetian blinds, in the direction of rotation of the grinding wheel, and are disposed obliquely relative to the horizontal between two upright plates (10,10') to which the slats are fixed by the ends of the slats. Openings (12) are provided in one plate (10') of the plates which carries the lowermost ends of the slats 11, in the region of these ends.

Abstract: The machine for grinding ophthalmic glasses comprises a housing (1) open in its upper part and housing a grinding wheel (7) driven in rotation on a first horizontal shaft (6), a U-shaped carriage (13) pivotally mounted on a second horizontal shaft (11) and located above and at the rear of the first horizontal shaft (6) and carrying between the wings of the carriage a shaft (14) in two parts which clamp therebetween a work piece (15) to be machined, the carriage being movable about and along the second shaft. The machine further comprises a hood (2) having a pivotal upper panel (5) and mounted in the housing (1) to be pivotable between an upper closing position and a lower opening position, a motor (20) for driving the hood, and a first device (26, 27) and a second device (24, 25) for raising the carriage and the panel respectively when the hood moves from its upper position to its lower position.

Abstract: This machine comprises a carriage movable in translation and in oscillation in a direction parallel to and perpendicular to a shaft carrying trimming and bevelling grinding wheels, and further comprises a tracer (7) adapted to come in contact with the edge of a trimmed blank (3) of the glass in a direction perpendicular to this edge, and adapted to measure the distance L1 of the edge of the front side of the glass (3) relative to the edge of a planar glass in respect of which L1=0, and the value L2 which corresponds to the thickness of the edge of the glass. The tracer (7) has a curvature which is identical to and concentric with the curvature of the grinding wheel (4, 11) and formed by a plurality of parallel elements (9) acting on a sensor (10).