Abstract: In a method of reading off the cross-section of the bezel of an eyeglass frame rim or surround at one point at least on the latter, a mobile feeler the position of which can be defined in a given system of coordinates is moved into line with the bezel. The head of the feeler successively sights at least two different points of at least one of the flanks of the bezel in order to deduce the coordinates of these points. The cross-section of the bezel read off in this way is used in trimming the lens to be mounted in the bezel.

Abstract: Method for renewing grinding wheel surfaces in a machine for grinding ophthalmic lenses, comprising one or more diamond wheels (2,3,4,5), gripping members (7,8) capable of receiving an ophthalmic lens, and control. Once wheel wear is detected, the surface is renewed using an abrasive disk (9) fitted to the grinding machine in place of a lens in the gripping members. The invention also concerns a disk (9) for carrying out the method, with at least the peripheral surface consisting of abrasive material. A machine for gripping ophthalmic lenses and carrying out the method is also described.

Abstract: A contour follower device suitable for reading off the contour of eyeglass frame rims or surrounds includes a support table with holding means for supporting the article whose contour is to be read off. A feeler has a rotatable contact head adapted to be applied to the article and is carried by a carriage which is movable relative to the support table. The contact head is rotated by rotational drive means such as a motor-gearbox unit.

Abstract: In a method for bevelling an ophthalmic lens, the lens is rotated about its own axis and is also displaced parallel to its axis as a function of its angle of rotation. Simultaneously, the edge of the lens is kept in contact with a grinding wheel. Thus the point of contact of the lens with the grinding wheel is constrained to follow a specific path. The specific path to be followed by the point of contact is an intermediate path selected between two paths resulting from a comparison between a collection of predetermined paths and two reference paths. The reference paths are each obtained from a plotting operation carried out prior to the bevelling operation on the ophthalmic lens using feelers. This method is used in grinding machines such that trimming and bevelling of ophthalmic lenses can be automatically performed.