Installation and process for controlling the centering of a laser beam passing through a laser nozzle

摘要

The installation for laser cutting or welding of materials e.g. metallic plates, comprises a machining head having a nozzle (1) with a central opening to allow the passage of laser beam, a system for determining a relative position of the nozzle with respect to a laser beam axis (A-A), a unit (3) for lighting a part of the nozzle, a unit for memorizing image, and a unit (6) for displaying images acquired before and/or after processing. The system comprises a unit for activating the alignment of the laser beam through the opening, and a unit to acquire an image of the external region. The installation for laser cutting or welding of materials e.g. metallic plates, comprises a machining head having a nozzle (1) with a central opening to allow the passage of laser beam, a system for determining a relative position of the nozzle with respect to a laser beam axis (A-A), a unit (3) for lighting a part of the nozzle, a unit for memorizing image, and a unit (6) for displaying images acquired before and/or after processing. The system comprises a unit for activating the alignment of the laser beam through the opening, a unit to acquire an image of the external region of the nozzle before and after activation of a laser beam alignment, and a unit for processing and analyzing the designed images. The images are compared before and after alignment of the beam to obtain a correct centering or decentering of the nozzle with respect to the axis of the laser beam. The acquisition unit comprises a video camera (2) equipped with optical filters and/or mechanical obturator. The image processing unit, the comparison unit and the memorizing unit are incorporated into a computer (5) and/or in an electronic card for acquisition and/or for processing. A unit is arranged for counting the number and/or duration of laser shots operated with the given nozzle. The image acquisition unit is controlled using a unit, when the counting unit determines more than a number-threshold value and/or threshold duration of shots or missed shots. A unit is used for analyzing a zone or circular-shaped region in the form of crown, which is determined and bounded around the central opening. An independent claim is included for a process of determining a relative position of the nozzle according to an axis (A-A) of the laser beam.