초록 ▼

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 grindi

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.

대표청구항 ▼

Apparatus for forming the edge of an ophthalmic lens by bevelling or grooving, said apparatus comprising a grinding wheel mounted for rotation about a first axis, means for mounting the ophthalmic lens for rotation about a second axis parallel to said first axis, means for maintaining said grinding

Apparatus for forming the edge of an ophthalmic lens by bevelling or grooving, said apparatus comprising a grinding wheel mounted for rotation about a first axis, means for mounting the ophthalmic lens for rotation about a second axis parallel to said first axis, means for maintaining said grinding wheel in contact with the edge of the lens, means for displacing the lens axially and radially relative to said first axis as a function of angular position of the lens with respect to said second axis, means for plotting first and second reference paths in a zone of a front face of the lens and in a zone of a rear face of the lens respectively, control means including means for storing a collection of predetermined bevelling or grooving paths and means for comparing first and second reference paths with the collection of predetermined paths and for selecting one of the bevelling or grooving paths which is intermediate the first and second reference paths from the collection of predetermined paths whereby said control means controls the displacement of said lens in accordance with the selected intermediate path to form the edge of the lens.