Machine for edging and bevelling ophthalmic lenses

Claim 1

In a machine for edging and bevelling ophthalmic lenses, in which a templet and a lens to be edged in accordance with the contour of said templet are supported by a spindle rotating at a low speed and having an axis of rotation parallel to a fixed direction, said spindle being rotatably mounted in a movable carrier operatively connected to a frame structure of the machine through coupling means allowing movements of said carrier both in a first direction parallel to said fixed direction and in a second direction perpendicular to said first direction, a feeler carried by the frame structure and cooperating with said templet to limit the penetration of a grinding wheel carried by the frame structure and rotating at a high speed into the edge of the lens, and in which guide means are provided for guiding the movements of said movable carrier in accordance with a predetermined curvature, said guide means comprising a guide member carried by said frame structure and a bearing member carried by said movable carrier urged for engagement with said guide member, one of said guide member and bearing member being adjustable in said first direction, the improvement comprising: (a) the guide member is connected to the frame structure of the machine by means of a pair of parallel links of same length forming a parallel motion coupling, (b) a pair of antagonistic springs constantly urge the assembly consisting of said guide member and of said pair of links to a stable position in which the longitudinal axes of said links form a predetermined angle with the axis of said spindle; (c) one of said guide member and bearing member comprises a bar extending parallel to said second direction, said bar having coupling means engageable with the other of said guide member and bearing member for preventing any relative movement between the guide member and the bearing member in said second direction.