Patent DE-102012221218-A1 (DE)
Title: Device, useful for quality assurance of products manufactured by laser beam processing, includes laser beam processing apparatus, laser beam source, deflecting unit, and unit for determining and recording temperature at processing position
Inventor: HOFFMANN VOLKER
IPC: B23K26/03
Filed: 2012-11-20
Abstract: The device comprises a laser beam processing apparatus, a laser beam source, a unit for deflecting a laser beam (5), a unit for determining and recording a temperature at a processing position and coordinates of the processing position of the laser beam, where the processing position is an incidence locus of the laser beam on the product to be processed, and a unit for controlling laser beam parameters on the basis of a determined data from temperature- and processing position determination in the form of a digital logical circuit. The device comprises a laser beam processing apparatus, a laser beam source, a unit for deflecting a laser beam (5), a unit for determining and recording a temperature at a processing position and coordinates of the processing position of the laser beam, where the processing position is an incidence locus of the laser beam on the product to be processed, and a unit for controlling laser beam parameters on the basis of a determined data from temperature- and processing position determination in the form of a digital logical circuit. The determining and recording unit: is an optical sensor and a beam splitter arrangement; comprises a unit for transferring and evaluating control signals; and determines the coordinates of the control signals in a real time. Sensor datas are recorded by a data memory. The digital logical circuit detects and corrects chromatic mistakes, spectral effects and geometric influences of optical components of the device for the laser beam processing. The optical sensor and the beam splitter arrangement decouple IR radiation in a real time from an optical path. A desired value for controlling the laser beam parameters, which are adjusted by the laser beam processing apparatus, and is compared by the control unit in real time with the determined and recorded temperature values and with determined, corrected and recorded coordinates of the processing position. The laser beam parameters are corrected in real time with deviations of the desired value over the control unit. The laser beam processing apparatus comprises a laser with a laser beam power of 100 W. The optical sensor is present in the form of two-beam pyrometers or multi-beam pyrometers. The IR radiation emitted by the beam splitter arrangement from the processing position is decoupled from a beam path of the laser beam at an angle of 40-50[deg] with respect to the laser beam. The deflecting unit contains a mirror, which comprises a coating reflected on a front side of the mirror to the processing position of an incoming laser radiation and on a back side of the mirror to the processing position, where the coating reflects the incoming emitted IR radiation. The determining and recording unit emits the IR radiation arriving from the processing position, and is recorded with the data memory. The determined values for the temperature at the processing position and the coordinates of the processing position are compared with the desired values. The recording unit comprises units for graphical and/or three-dimensional representation and storage of the determined data.