METHOD FOR DETECTING AN IDENTIFICATION MARK INVISIBLE TO THE NAKED EYE ON THE SURFACE OF A VALUABLE ARTICLE A METHOD FOR POSITIONING IT OVER THE COURSE OF DETECTION AND A DETECTOR FOR PROCESS IMPLEMENTATION

摘要

This detection method is performed in the following manner. Article 3 is placed and secured on positioning tool (PT) 4 so as to ensure that center 5 of the surface in question (SIQ), 2, lines up with optical axis 6 of the viewing tool. PT 4 is secured in the axial direction relative to optical system (OS) 8. The backlighting of SIQ 2 by light beam 9 from source 10 is arranged. During the last step, the user views and observes mark 1 in the reflected light beams, 11, by means of adjusting the viewing tool (for example, eyepiece 12) of OS 8. A self-centering clamping device with two reciprocally moving jaws, 14 and 15, that have retaining surfaces, 16 and 17, and seating surfaces, 18 and 19, respectively, is used as PT 4. Over the course of positioning, surface 2 of article 3 bearing mark 1 is placed in the plane of seating surfaces 18 and 19 of the clamping device�s jaws 14 and 15. The distance from the center of SIQ 2 of article 3 to focal point F of eyepiece 12 ensures a constant value for a predetermined range of standard sizes of the articles, 3, undergoing detection. To this end, the mutual spatial immobilization of PT 4 and OS 8 in the axial plane is accomplished in the same position for which the one-time adjustment of the eyepiece is also ensured. The following are distinctive features of the positioning method. Before article 3 is placed and secured on PT 4, the article 3 surface bearing mark 1 is lined up with independent reference plane 20. Seating surfaces 18 and 19 of jaws 14 and 15 in the separated position are then brought into contact with plane 20, thereby ensuring the capture of article 3 by retaining surfaces 16 and 17, and it is secured. Thereafter, PT 4 and OS 8 are secured in the predetermined position. This detector is envisioned for the implementation of the methods. 3 independent claims (i.c.), 5 illustration (il.)