Method for verifying the accurate mounting of molding inserts to a tooling plate of an injection-molding apparatus for molding ophthalmic lens molds
AssigneeAlcon Inc.
InventorsJan Bernard, Michael Stutz, Thomas Tonn
Life of this patent
Estimating the term…
Abstract
To achieve molding insert is properly mounted to the tooling plate of the injection molding machine, a sensor head comprising confocal sensors is used. The sensor heads are placed on the tooling plate at the respective position to determine whether the desired mold insert has been mounted to that position and whether the desired mold insert has been precisely and accurately mounted to the tooling plate.
Claims11
A method for verifying whether a molding insert (1a, 1b) is accurately mounted to a tooling plate (2a, 2b) of an injection-molding apparatus for molding ophthalmic lens molds, the tooling plate (2a, 2b) having a mounting axis (21a, 21b) for the molding insert (1a, 1b), the method comprising the steps of:
- a) providing a confocal sensor (3a, 3b) having a measurement beam (31a, 31b);
- b) arranging the confocal sensor (3a, 3b) relative to the tooling plate (2a, 2b) such that a reference plane (32a, 32b) of the confocal sensor (3a, 3b) as well as a reference plane (22a, 22b) of the tooling plate (2a, 2b) are normal to the mounting axis (21a, 21b), with the reference plane (32a, 32b) of the confocal sensor (3a, 3b) being spaced from the reference plane (22a, 22b) of the tooling plate (2a, 2b) by a predetermined first distance (d1, e1);
- c) with the aid of the measurement beam (31a, 31b) of the confocal sensor (3a, 3b), measuring a second distance (d2, e2) between the reference plane (32a, 32b) of the confocal sensor (3a, 3b) and a central impingement location (11a, 11b) of the measurement beam (31a, 31b) on a molding surface (12a, 12b) of the molding insert (1a, 1b);
- d) based on the measured second distance (d2, e2) as well as based on the predetermined first distance (d1, e1), determining a third distance (d3, e3) of the central impingement location (11a, 11b) on the molding surface (12a, 12b) of the molding insert (1a, 1b) relative to the reference plane (22a, 22b) of the tooling plate (2a, 2b);
- e) comparing the determined third distance (d3, e3) with a predetermined target distance, and
- f) determining that the molding insert (1a, 1b) is accurately mounted to the tooling plate (2a, 2b) if the difference between the determined third distance (d3, e3) and the predetermined target distance is less than a predetermined threshold difference.
A system for verifying whether a molding insert (1a, 1b) is accurately mounted to a tooling plate (2a, 2b) of an injection-molding apparatus for molding ophthalmic lens molds, the system comprising:
- a confocal sensor (3a, 3b) having a measurement beam (31a, 31b) and a confocal sensor reference plane (32a, 32b);
- a tooling plate (2a, 2b) having a mounting axis (21a, 21b) for a molding insert (1a, 1b) and a tooling plate reference plane (22a, 22b) normal to the mounting axis (21a, 21b);
- wherein the confocal sensor reference plane (32a, 32b) and the tooling plate reference plane (22a, 22b) are arranged parallel to each other normal to the mounting axis (21a, 21b) and spaced from one another by a predetermined first distance (d1, e1);
- a molding insert (1a, 1b) mounted to the tooling plate (2a, 2b) and having a molding surface (12a, 12b), and
- a processor (5) configured to determine, based on a measured second distance (d2, e2) between the confocal sensor reference plane (32a, 32b) and a central impingement location (11a, 11b) of the measurement beam (31a, 31b) on the molding surface (12a, 12b) of the molding insert (1a, 1b) as well as based on the predetermined first distance (d1, e1) between the confocal sensor reference plane (32a, 32b) and the tooling plate reference plane (22a, 22b), a third distance (d3, e3) of the central impingement location (11a, 11b) on the molding surface (12a, 12b) of the molding insert (1a, 1b) relative to the tooling plate reference plane (22a, 22b), and further configured to determine that the molding insert (1a, 1b) is accurately mounted to the tooling plate (2a, 2b) if the difference between the determined third distance (d3, e3) and a predetermined target distance is less than a predetermined threshold difference.
Dependencies are inferred from the claim text.