Analysis device and method for monitoring the condition of a protective glass of a production plant and production system for producing a workpiece
The analysis device addresses contamination and damage in protective glasses by directly detecting and localizing issues, improving manufacturing quality through precise evaluation and integration into existing systems, enabling timely maintenance and enhanced optical production processes.
Patent Information
- Application Number
- DE102022112524
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-05-18
- Publication Date
- 2025-09-25
- Estimated Expiration
- 2042-05-18
AI Technical Summary
Existing manufacturing systems face issues with contamination and damage to protective glasses, leading to reduced precision and quality in optical production processes due to passive measurement techniques that only detect optical properties and not the contaminants themselves, and are not easily integrated into existing installations.
An analysis device comprising an optical sensor and exposure device that directly detects and localizes contamination, damage, and aging on protective glasses, allowing for precise evaluation and integration into existing production facilities without interference.
Enables precise, non-invasive detection and evaluation of protective glass states, facilitating timely maintenance and improving manufacturing quality by predicting cleaning or replacement times, thus enhancing the efficiency and accuracy of optical production processes.
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Abstract
Description
[0001] The present invention relates to an automatable manufacturing system based on optical interaction, in particular a manufacturing system for selective laser melting (SLM), and an integrable analysis device in which the contamination, damage, and / or aging state of one or more protective glasses integrated into the manufacturing system is determined by optical detection and analysis of an object plane assigned to the manufacturing system. Furthermore, the present invention relates to a manufacturing system for the automated production of workpieces by irradiating a material to be processed, which enables an assessment of the condition and / or service life of the protective glass with the aid of signal exchanges between the integrated analysis device. Background of the invention
[0002] Due to increasingly complex work processes and the resulting requirement to be able to manufacture as precisely, automatically and on a large scale as possible, the production and processing of workpieces based on optical interaction processes has become established.
[0003] Manufacturing systems known from the prior art and based on optical interaction, such as laser-induced and / or additive manufacturing steps, such as selective laser melting, usually comprise one or more high-intensity light sources which are coupled to a plurality of finely adjusted optical elements (lenses, mirrors, filters, etc.) which can be controlled automatically via a computer system and thus allow a plastic effect on a desired workpiece or a desired material by generating a condensed light beam focused on a specific manufacturing point.For example, a manufacturing plant using the selective laser melting process has at least one laser light source which, by means of software-supported optics, can focus a bundled laser beam onto powdered layers of materials to be processed and thus create an extremely effective, three-dimensional manufacturing process through local, layer-by-layer fusions.
[0004] Despite the continuous development of such manufacturing systems, the problem still arises in most such systems: due to contamination or processing residues arising during the manufacturing process, the components required to transmit the optical processing beam can become contaminated or even damaged. This leads to a reduction in exposure precision and, consequently, a deterioration in the quality of the workpiece during ongoing manufacturing processes. For example, such manufacturing systems have at least one (e.g., translucent) protective glass, which is positioned between the light-conducting optics or the light source and a processing station used to manufacture the workpiece to protect the optical elements and can therefore inevitably come into contact with the aforementioned process emissions.Contamination or damage to the protective glass, however, poses a variety of problems: Firstly, clouding of the protective glass can occur, which adversely affects the light path, for example, reducing the intensity of the processed light beam. Furthermore, it is also possible that individual light scatterings occurring in areas of contamination or damage can lead to a shift in the beam profile, which not only leads to noticeable quality fluctuations within the production line, but also causes the deflected or absorbed energy of the light source to generate further damage (e.g., melting, breakage, or cracking) within the protective glass.Accordingly, it is critical for optical manufacturing plants to develop the most precise analysis possible for identifying any abnormal conditions, such as contamination and damage, which is capable of both enabling an assessment of the degree of contamination or damage of a protective glass implemented in the manufacturing plant within existing manufacturing processes and integrating this assessment mechanism into the manufacturing plant as non-invasively and efficiently as possible.
[0005] DE 10 2014 203 798 A1 relates to a method for monitoring the contamination and / or damage status of a protective glass of a laser processing head attached to a robot, for which purpose the robot moves the laser processing head into the field of view of a stationary camera device.
[0006] EP 1 354 664 A1 also relates to a device for monitoring an optical element of a processing head of a machine configured for thermal processing, in particular a laser processing machine. Said device comprises, in particular, a separate light source for coupling a light beam onto a side of a protective glass surface facing away from a workpiece, as well as a detector for detecting beams reflected from the surface.
[0007] Furthermore, DE 101 13 518 A1 also relates to a method for measuring the degree of contamination of a protective glass within a laser processing head, wherein a first radiation detector arrangement arranged outside the laser beam used detects an area of the protective glass penetrated by the laser and compares any reflection beam intensities with a predefined reference intensity value.
[0008] However, known methods and devices have the problem that, due to their purely passive measurement techniques (the methods measure the effects of "contamination," but not the contamination itself), no direct statement can be made about the degree of contamination of a protective glass in use. Instead, only optical properties of the protective glass, which can therefore also be influenced by other sources (bending, aging processes within the material), can be identified. Furthermore, known devices are neither capable of spatially localizing contamination accumulations (since the measured scattered light can potentially originate from any part of the illuminated area), nor can they be meaningfully integrated into existing production systems, since any scattered light measurements require a system geometry specifically designed for this purpose.
[0009] An object of the present invention is to provide an optimized manufacturing system for additive manufacturing with which improved manufacturing quality can be achieved. Furthermore, an object is to provide an integrable analysis device with which the status of the manufacturing system can be efficiently monitored and a manufacturing method for the optimized production of workpieces using additive manufacturing.A further object is to remedy the problems of the prior art mentioned and, in particular, to provide an analysis device for detecting conditions, in particular conditions of contamination, damage and / or aging, on one or more protective glasses of a production plant based on optical interactions, which can detect even local changes in condition, such as individual contamination and / or damage structures, and thus make the assessment of degrees of contamination, damage or aging even more precise and effective.Furthermore, it is an object of the present invention to provide an analysis device that can be integrated as easily as possible into the process flow of existing production plants, which can use the additional information obtained by the condition localization to determine predefined evaluation parameters, as well as to monitor and predict possible cleaning and / or replacement times of a protective glass. Detailed description of the invention
[0010] To achieve the above-mentioned object, the features of the independent claims are proposed. The dependent claims relate to preferred embodiments of the present invention.
[0011] The analysis device of the present invention can preferably comprise at least one optical sensor device for detecting an object plane belonging to the protective glass or the protective glasses of the production plant, i.e. lying directly on the protective glass, as well as an exposure device for exposing the object plane (in the preferred case detected by the sensor device), which are preferably set up to determine existing protective glass conditions using the exposure device, especially by exposing structures occurring on a protective glass, such as contamination, damage or aging structures (e.g. contamination: process by-products such as smoke particles, melts, but also residues of improper cleaning such as streaks, fibers and / or (dust) particles; damage: scratches, chipping, burns or damaged coatings and aging phenomena such as e.g.Bleaching within the protective glass) for the above-mentioned optical sensor device and to localize the mentioned structures accordingly using the optical sensor device. The present analysis device thus preferably forms at least a two-part device system which, with the help of the first device (the optical sensor device), is capable of directly and spatially resolving identifying abnormal conditions on one or more protective glasses, such as contamination and damage, whereas the second device (the exposure device) ensures the most precise and uniform visualization of the above-mentioned structures, designed for the optical sensor device.Consequently, the present invention makes it possible to provide an analysis device which can determine the condition of one or more protective glasses not by given optical (and thus influenceable) secondary effects, but in particular by the direct identification of individual bodies and / or malformations found on the protective glass, thereby realizing a far more precise and error-resistant detection mechanism.
[0012] Possible alternative embodiments of the present invention may also include, in particular, further simplifications of the above-mentioned analysis device. For example, it may equally be possible for an external illumination source, for example a build space light integrated within the corresponding production facility, to be used in addition to or instead of the previously described illumination device in order to detect any anomalies of the above-mentioned protective glass, whereby, in particular, an even more compact and thus easier to integrate analysis device into a production facility can be provided. Accordingly, in a further, particularly preferred embodiment, the analysis device may, for example, also be designed at least in such a way that it only comprises the above-mentioned sensor device, but not the illumination device, and the condition of the protective glass to be assessed, e.g.due to the externally or otherwise generated exposure, can be analyzed solely by this sensor device.
[0013] The optical sensor device itself comprises at least one optical sensor, such as a photodiode, a CCD sensor, a CMOS sensor, or a sensor system connected to an optical sensor, which can be coupled to correspondingly controllable optics, such as focus or scattering lenses, mirrors or optical filters, in order to detect the above-mentioned object plane belonging to the protective glass / protective glasses and is thus able, depending on the optical properties of the above-mentioned elements, to focus on at least one arbitrary three-dimensional point within the given system to be measured.Accordingly, in a preferred case, the detection of the object plane described above can also be understood at least as signal detection, in which a signal emanating from the focal plane of the optical sensor device can be guided to the respective sensor (image plane) and thus identified and evaluated in further process steps.
[0014] Based on these properties, the optical sensor device is accordingly configured, in particular, to generate an at least one-dimensional image of the respective detected object plane from the above-mentioned signals. The optical sensor of the optical sensor device is also designed, in particular, as an imaging sensor, for example, by implementing a sensor based on a single or multiple pixels and / or a coupled, scannable lens system, so that each point of the object plane detected by the optical sensor device can be identified as an element of a spatially resolved, at least one-dimensional, but in particularly preferred cases, primarily two-dimensional image.Subsequently, with the aid of the optical sensor device, it is possible, depending on the selected orientation of the implemented optics, to focus preferably any plane connected to one or more protective glasses (object plane) and to reproduce it spatially resolved as a one- or two-dimensional, signal-dependent image.
[0015] In order to ensure the most accurate identification possible of existing structures found on the protective glass, such as the above-mentioned contamination, damage and / or aging structures, the aforementioned object plane of the sensor device can also preferably be positioned parallel to and at the level of the contaminated optical surface (in particular an outer surface of the protective glass facing the process area) for the precise assessment of the condition of a protective glass, whereby maximum image sharpness can be achieved with regard to particle identification.Alternatively, however, it may equally be possible to define several object planes, for example located at different heights or in different cross-sectional axes of the protective glass, which can be approached, preferably one after the other, by preferably automatic control of the optical elements located in the sensor device and thus used to generate further measurement data.
[0016] Accordingly, for example, in addition to the above-mentioned two-dimensional images of the contamination, damage, and / or aging structures located on a protective glass, a three-dimensional representation of the elements located in the detected object planes, based on multiple imaging planes, can also be generated, which enables additional information, such as the shape or height of the structures accumulating on a protective glass. Likewise, the optical sensor device can preferably also be configured to detect only individual, local areas within a specific plane, in particular to allow maximum resolution within the individual images generated by the sensor device. This allows, for example, the pixel-to-image rate to be increased as desired in sensor devices based on pixel sensors.For this purpose, the sensor device can also preferably be equipped with further image-enhancing mechanisms, such as an autofocus, dichroic filters or filters defined on specific wavelengths, or software-based image processing processes, which preferably automatically adjust the sharpness and information content of the recorded images both during and after the recording process and thus enable optimal detection of the contamination state.
[0017] The signal to be detected by the optical sensor device can, as already mentioned above, preferably be generated by illuminating at least the object plane to be detected by the illumination device implemented in the analysis device or by an external illumination source. In a particularly preferred embodiment, the illumination device can emit monochromatic or multichromatic light at a predefined angle of incidence onto a protective glass to be analyzed or the object plane associated with the protective glass. The interaction of the light irradiated by the illumination device with the contamination, damage, and / or aging structures adhering to the protective glass can generate a signal field dependent on the latter structures.
[0018] Thus, in a first preferred embodiment, the exposure device can furthermore preferably be arranged, in particular, as an incident light source oriented with respect to the previously described sensor device. Accordingly, in this case, the exposure device is configured to generate the light generated for illuminating at least one protective glass from the side of the protective glass facing the optical sensor device and to allow it to strike the protective glass, so that, given a completely clean or defect-free surface of the protective glass, the exposure emanating from the exposure device can pass through the protective glass completely, i.e., essentially without reflection, and thus cannot strike the optical sensor device.Based on this structure, the scattered light generated by the respective contamination, damage, and / or aging structures can be used as the sensor signal of this exemplary embodiment, for example, to efficiently and locally identify the structures and thus the contamination, damage, or aging state of the protective glass, since any light (naturally) emanating from the exposure device can be effectively kept away from the optical sensor device. Consequently, the detection process of the analysis device in this embodiment of the exposure device provides for the illumination of the object plane or area to be detected by the optical sensor device to be as homogeneous as possible by the exposure device.of at least one protective glass belonging to the object plane and to detect the scattering patterns thus generated on the contamination, damage and / or aging structures of the protective glass in order to localize the individual structures on the sensor device.
[0019] To improve the aforementioned process, the exposure device can, in addition to an exposure light source required for exposure, such as an LED, a light-emitting diode system, or a laser, also comprise further elements, such as additional polarization, intensity, or color filters, focus and scattering lenses, or condensers suitable for beam homogenization (e.g., honeycomb condensers), which are preferably coupled to the exposure light source and can be controlled both manually and automatically. Accordingly, in a preferred case, the optical elements of the optical sensor device and the exposure device of the present invention can also act in a coordinated manner and, depending on the selected settings within one device, bring about automatic adjustment of the elements of the other device.For example, the exposure device can be configured to change the light intensity generated by the exposure light source, for example depending on external parameters, or to adapt its spectral bandwidth by introducing additional filters, whereby filter or optical elements located in the optical sensor device are automatically added or removed for improved analysis.
[0020] To further improve the exposure quality, the exposure device can also be configured to illuminate the object plane detected by the optical sensor device continuously or in pulsed mode, or to efficiently adjust the angle of incidence of the light used for illumination at least by mechanically reorienting the exposure device. Similarly, multiple exposure light sources or optical elements coupled to them can be provided, or, equivalent to the optical sensor device, only predefined partial areas of the detected object plane can be illuminated by the exposure device, thereby enabling particularly high exposure intensities.
[0021] Further embodiments of the exposure device can also preferably also comprise the use of other types of exposure. For example, in a second preferred embodiment, the exposure device can also be set up, contrary to the incident light process of the above-mentioned first embodiment, to implement transmitted light illumination to be used for detecting the contamination, damage and / or aging structures. For this purpose, the exposure device can, for example, in a particularly preferred case, be mounted at least on the side of the at least one protective glass to be detected that faces away from the optical sensor device (and at a distance from the protective glass), so that the protective glass illumination generated by the exposure device in the error- orIn a contaminant-free state, the light reaches the protective glass and illuminates it without reflection, and also hits the individual pixels of the sensor device located behind the protective glass.
[0022] Accordingly, in this embodiment it is equally possible to detect individual soiling, damage and / or aging structures on one or more protective glasses, in that in this case not the scattered light emanating from the structures can be localized, but, vice versa, the loss of intensity of the light arriving at the sensor device caused by the scattering of the transmitted light at the structures.Consequently, the previously described embodiments of the exposure device can differ, in addition to the positioning of the exposure device per se, in particular in that the contamination, damage and / or aging structures to be detected in the first embodiment are expressed in the image generated by the optical sensor device as geometries with a much higher intensity compared to the detected background radiation, whereas the detected image background of the second embodiment generally has strong signals due to the additionally detected transmitted light illumination, but shows a significant signal reduction at supposed structural locations.Thus, both of the aforementioned embodiments can realize an efficient and at the same time precise methodology for the spatially resolved identification of any protective glass states, which can further take into account both preferred device positions and exposure types to be used.
[0023] Further embodiments of the above-mentioned exposure device can also preferably also comprise a combination of the aforementioned types of exposure, for example by introducing light sources in a space located in front of and behind the protective glass with respect to the position of the optical sensor device, by attaching the exposure device directly to the optical sensor device or even by omitting the exposure device and exposing the protective glass solely by external exposure sources, such as a room light present within the associated production plant, whereby in particular an extremely compact form of the analysis device can be generated.In a further embodiment, which can be identified as the third, the exposure device can also preferably be mounted laterally on the surface of a protective glass to be detected (in particular, as LEDs arranged laterally on the narrow side of the respective protective glass or LEDs arranged in a ring shape), so that, in comparison to the previously mentioned cases, radial exposure, i.e., exposure from the outside of a protective glass to its center, can be realized. The latter makes it possible to generate, in particular, lateral irradiation of the protective glass structures to be analyzed, thereby resulting in further advantageous effects for the detection processes to be carried out by the optical sensor device.
[0024] Accordingly, it is evident that the detection mechanism to be generated using the present analysis device enables an effective and at the same time more precise analysis of the conditions existing on at least one protective glass. Furthermore, it should be noted that the aforementioned simple design of the present analysis device, consisting of only one or two device elements (the optical sensor device and (optionally) the exposure device), allows for much more flexible adaptation to the respective conditions occurring within different production plants.
[0025] For example, due to the direct analysis of the at least one protective glass by the sensor device (and thus independent of any elements introduced into the production facilities), the analysis device of the present invention can, in a preferred case, also be designed as an analysis unit that can be integrated into already existing production facilities, whereby in particular the technical added value of the present invention is further increased.
[0026] As a result, it may also preferably be possible in the present invention to incorporate the previously described device elements of the analysis device, in particular without interference, into the structure of a respective production plant based on optical interactions.
[0027] For this purpose, the analysis device can preferably be configured to be integrated or positioned at least along the light path of the production system created by the manufacturing light source, so that not only can the shortest possible detection distance be established between the above-mentioned optical sensor device and the at least one protective glass to be analyzed, but equally, corresponding free spaces existing in the production system can be utilized for the integration of the respective device elements. For example, due to the optical properties and the resulting working distances of the optical production elements defining the light path, recesses exist in production systems based on optical interactions that are solely used for beam manipulation (focusing, scattering, expansion, etc.).) of the light beam used for production and can thus potentially be used to integrate further devices. Accordingly, in a particularly preferred case, the analysis device of the present invention can be designed in particular to use precisely such free spaces within a production plant and to incorporate its existing device elements, or at least the optical sensor device, into these free spaces for efficient integration without damaging the production process. Consequently, the above-mentioned positioning results in the advantages that the optical sensor device can be arranged not only in a particularly space-saving manner, but equally also in a manner that is particularly independent of the usual production processes, whereby the former can be effectively protected, at least additionally, from any contamination and / or damage.
[0028] Consequently, in a particularly preferred embodiment, the optical sensor device of the present analysis device can be configured to be arranged at least between the light source and the protective glass of the production plant for efficient integration of the analysis device into the production plant, so that the free spaces existing along the light path of the production plant can be effectively utilized.
[0029] In a preferred embodiment, the optical sensor device can preferably be configured to be integrated at least between the light source and the optical manufacturing elements of the manufacturing system configured to modify the finished light beam, thereby enabling the free spaces between the optical manufacturing elements to be effectively utilized. Likewise, in this case, it may also preferably be possible for the optical sensor device to be integrated into the light path of the optical manufacturing elements, for example, by implementing additional mirror axes, so that existing parts of the manufacturing system can also be effectively utilized for the detection of the protective glass or the object plane associated with the protective glass, enabled by the sensor device.
[0030] In a further preferred embodiment, the optical sensor device can also be configured, in particular, to be arranged between the above-mentioned optical production elements and the at least one protective glass of the production plant. Accordingly, the optical sensor device can preferably be designed to be positioned in the free space of the production plant used for the ultimate focusing of the manufacturing light beam onto the material to be manufactured, which preferably enables the sensor device to detect the protective glass to be analyzed directly, i.e. without the aid of further optics present within the production plant. In this respect, the sensor device in this embodiment has the particular advantage of realizing an equally precise and independent detection of potential protective glass states by directly measuring the one or more protective glasses.
[0031] Furthermore, as already mentioned above, the exposure device of the present analysis device can also be configured to be arranged in one of the previously described positions or free spaces of the production facility. Preferably, the exposure device can be positioned, in particular, in a free space to be occupied jointly with the sensor device, so that the analysis device can be integrated into the production facility as a whole, i.e., as a physically identifiable object.
[0032] However, in order to ensure functionality in different production plants, the precise positioning of the corresponding device elements of the present analysis device can be adapted depending on the design of the production plant to be equipped. For this purpose, it can be achieved by means of additional, preferably mechanical structures attached to the device elements, such as adjustable springs, rails, or angle mechanisms, by shifting and reorienting the device elements. To ensure the highest possible safety and detection quality, the previously described device elements can also preferably be attached to a permanently installed and preferably displacement-free structure, such as a framework structure, so that any influences acting on the analysis device and impairing its process quality can be reduced to a minimum.
[0033] In a particularly preferred embodiment, the analysis device can also comprise at least one independent protective housing for this purpose, in which the optical sensor device and / or the exposure device can be incorporated and which equally protects the latter from any process emissions occurring in the production plant, such as dust, smoke, or material residues. Accordingly, the aforementioned protective housing can preferably be configured to enclose the previously described device elements at least laterally, but in particularly preferred embodiments also completely, i.e., from all sides, so that a preferably inert space can be created by the protective housing.
[0034] The determination of the respective condition of the protective glass or glasses to be examined by the analysis device can preferably be made possible by evaluating the information generated by the optical sensor device, such as the signal values or the intensity values of the above-mentioned image of the respective detected object plane belonging to the protective glass.
[0035] In this respect, the analysis device can preferably be configured to initially transfer the previously described information, at least as digital information files, to a storage device provided and connected to the sensor device, in which storage device the information can be stored permanently or for a predefined period of time and thus made available for further evaluation processes. The connection between the sensor device and the storage device can be established via a physical connection, such as a cable or direct integration of the storage device, for example, as an integrated memory chip or hard disk, or also via wireless communication, such as Bluetooth, Wi-Fi, or infrared signals, so that, depending on the selected embodiment, extremely efficient data transfer can be enabled at all times.
[0036] For further evaluation of the information files stored in this way, the analysis device can then, in a first embodiment, be configured to send predefined components of current or previously acquired or processed information to a preferably optical output unit, such as a screen present on the production line, and thus to allow at least a manual assessment of the current protective glass condition by existing specialist personnel.Accordingly, it may be possible, for example, in the case of an imaging sensor device, for the image of the detected object plane generated by the optical sensor device (and consequently the (contamination, damage, and / or aging) conditions visible thereon) to be generated as a visual, at least two-dimensional image on the output unit, which can subsequently be used to estimate the current protective glass condition through the assessment of expert personnel or automatically by a corresponding computer program. Likewise, the output unit can also preferably be configured to receive information data from various recording steps and / or times and to present the specialist personnel with corresponding temporal progressions or changes in recorded, selected signals.
[0037] In a further embodiment, the present analysis device can also, in addition to or instead of outputting acquired information for manual analysis of existing protective glass conditions, preferably also comprise at least one evaluation unit for automated evaluation of the above-mentioned information. The evaluation unit itself can preferably be arranged as an independent computing unit, for example as a processor connected to the other device elements of the analysis device, and in particular can be configured to use the information generated by the sensor device to evaluate the protective glass condition by means of computing rules implemented or programmed in the evaluation unit.
[0038] For this purpose, in a preferred case, the evaluation unit can also be connected at least to the above-mentioned storage device of the analysis device, thereby enabling the latter to access the information data stored within the storage device and potentially incorporate both newly generated information and information generated by previous analysis processes into the evaluation process. In a particularly preferred case, the evaluation unit can also be configured to incorporate further parameters, such as predefined limit values, physical constants, or information generated by the generation of the information files, such as metadata, into the process, thereby enabling, in particular, complex evaluation mechanisms based on multiple conditions.
[0039] The evaluation process itself carried out by the evaluation unit can preferably initially comprise at least the determination and output of a condition degree defining the condition, in particular the contamination, damage and / or aging condition, of the at least one protective glass, hereinafter also referred to as the degree of damage, contamination or aging, which is particularly designed to represent the current condition of one or more protective glasses and the associated measures in a simple manner. Accordingly, the condition degree can be represented in a preferred form, for example, as a simple number, for example in a scale format from 1 to 100, in which a low (condition degree) number represents an inferior condition and a high one a good, i.e.preferred, fault-free and / or high-quality condition of a current protective glass, whereby, in particular, a given specialist personnel, upon identification of the output, current condition level of the respective protective glass, can be effectively guided both in the assessment of the current protective glass condition and the subsequent measures to be taken, such as cleaning or replacing at least one protective glass. In addition to or instead of the above-mentioned scale format, the condition level calculated by the evaluation unit can also contain more discrete information, such as the type of protective glass condition (e.g. physical damage to the protective glass, identified contamination layers, streaks, etc.) or an assessment given by the analysis device for the further process flow (e.g.“Continuation of the process”, “required cleaning” or “required replacement of the protective glass”) so that even unskilled personnel can identify existing problem sources and initiate further maintenance processes efficiently.
[0040] Accordingly, the calculation and output of the above-mentioned degree of condition by the analysis device can be used in particular to generate an automated and at the same time easily understandable assessment of the current condition of at least one protective glass detected by the optical sensor device, so that on the one hand a time required for the restoration / cleaning of the protective glass can be estimated with the greatest possible precision, but on the other hand also the quality of the latter restoration processes can be efficiently checked, especially for the subsequent problem-free recommissioning of the corresponding production plant.For example, it may equally be possible for the analysis device to be set up, in particular after a corresponding cleaning and / or replacement process of a protective glass, to check the condition of the processed protective glass again and to alert the current operator of the production plant to possible inefficient cleaning steps or an error that occurred during the renewed protective glass integration by issuing a discrete statement based on this check (e.g. a message such as "cleaning successful / completed", "protective glass still faulty", "streaks / damage detected"), whereby any process sequences carried out within the production plant can be further improved.
[0041] In order to determine the above-described current protective glass condition or the degree of condition to be used for this purpose, the evaluation unit can preferably be set up both to extract and evaluate predefined information from the signal values generated by the optical sensor device and to compare this with a plurality of reference information stored in the storage device, such as signal values from previous analysis processes or the additional parameters already mentioned above, so that the degree of condition to be calculated can preferably be identified at least as a comparison value between the currently detected condition of at least one protective glass and a previous point in time, for example a point in time at which the protective glass was condition-free, i.e. for example free of damage and / or contamination.In a particularly preferred embodiment, for this purpose, for example, an already predefined information file can be stored in the storage device, which shows the protective glass condition specifically directly after installation in the production machine or a cleaning process, and thus allows the evaluation unit, by using this information, to calculate the degree of condition, in particular as a comparison between the current and an optimal condition.
[0042] As information preferably to be used to determine the degree of condition and obtained from the optical sensor device, the evaluation unit can also be configured to calculate said degree of condition at least on the basis of the intensity values present in the images of the sensor direction.
[0043] For example, in a first exemplary embodiment, the evaluation unit can be configured to analyze at least the intensity values within the given image of the sensor device and subsequently calculate the desired state level at least by forming a relative difference value between the above-mentioned intensity value of the current image (for example, by calculating image-related averages) and that of a previous protective glass state, such as the previously described optimal state. This has the particular advantage that, due to the given correlation between the light intensity recorded by the sensor device and the strength of contamination orDamage or signs of aging on the detected at least one protective glass (the greater the contamination / damage / aging fading, the greater the intensity differences caused by the scattering effects), a simple and efficient measure of the damage, contamination, or aging of the given protective glass can be generated and thus used as a basis for the condition level to be calculated. Accordingly, the determination of the condition level in this first exemplary embodiment can at least provide for calculating the above-mentioned difference intensity value and subsequently converting it into the desired condition level using further process steps, such as comparison with predefined limit values or the implementation of further parameters.
[0044] In a particularly preferred embodiment, the evaluation unit can also be configured to include, in particular, any two-dimensional information within the generated images enabled by the imaging sensor device in the calculation. For example, the evaluation unit can be capable of using, in addition to or instead of the above-mentioned intensity values, the number and / or size of the contamination, damage, and / or aging structures depicted in the images to determine the degree of condition, thereby generating an analysis process that is independent of any optical values and thus more precise than the prior art.
[0045] For this purpose, the calculation of the state level based on this second exemplary embodiment can initially comprise at least the detection of any structural outlines or geometries found in the respective image, which can preferably be carried out equally depending on the intensity values found in the image. For example, the detection process for this purpose can comprise a segmentation step in which the evaluation unit extracts the intensity values of individual pixels from the image to be analyzed and identifies connected bodies, such as adjacent pixel groups, which, for example, have a predefined intensity value or exceed a certain threshold, as one of the aforementioned structural geometries.Accordingly, the additional information thus obtained, such as the pixel positions of the pixels belonging to a specific pixel group / structure or a specific intensity value, can be used to generate precise information about the size, geometry or any agglomeration areas of the contamination, damage and / or aging structures captured in the image, which can equally be incorporated into the calculation of the degree of condition and subsequently enable a very precise condition evaluation based on direct, i.e. actually existing, properties of the protective glass.
[0046] Based on these circumstances, the evaluation unit can therefore preferably be set up to integrate at least one of the above-mentioned properties of the detected damage, contamination and / or aging structures in addition to or instead of the aforementioned intensity values of the image into the subsequent determination of the condition level. For example, the condition level can be defined, at least partially, as a function of the area occupied by the detected structures (preferably relative to the total area of the generated image), so that the condition level becomes qualitatively lower with increasing wetting of the at least one protective glass. Alternatively, the number of detected structures, their size, shape or even the structure density orthe position of the individual structures identified within the image are included in the calculation and combined with each other using various calculation methods, such as predefined weightings, so that the final condition level can also be understood as an evaluation of various events occurring on at least one protective glass.
[0047] In this respect, the above-mentioned two-dimensional identification process and the calculation of the condition level based thereon have the particular advantage that an automated assessment of the protective glass condition can be produced, which not only uses any effects caused by contamination, damage and / or aging of a protective glass, but can also include explicit properties of the structures located on one or more protective glasses (process emissions, damage sites, local bleaching, etc.).
[0048] Further potential advantages may also arise from additional process and / or analysis steps. For example, it may preferably be possible for the evaluation device, after locating any structures on a protective glass, to also label the latter with a predefined structure type (e.g., "dust residue," "smoke deposits," "scratches," "crack," "fading," etc.) (e.g., by comparing the previously mentioned structure geometries) and to adapt the degree of protection according to the respective analyzed structure types. For example, in the case of structures identified primarily as dust, the evaluation device can generate an output to clean the protective glass, whereas if a majority of cracks are identified, the replacement of a respective protective glass can be suggested.Accordingly, it is evident that the additional two-dimensional information of at least one protective glass obtained with the aid of the imaging sensor device can also enable much more specific condition analyses (and corresponding treatment steps) to be realized.
[0049] In a particularly preferred embodiment, the evaluation device can also be configured to divide the image of the detected object plane generated by the optical sensor device into a plurality of different evaluation regions, which in particular makes it possible to separately consider any local influences acting on a protective glass and to include them for a more precise assessment of the degree of condition or the general manufacturing process. For example, it may be possible that, particularly in heatable manufacturing systems, any structural agglomerations caused by temporary temperature differences can form on a protective glass, which can lead to a local increase in the structural density within the generated image, but can have little influence on the overall manufacturing quality of the manufacturing plant due to the merely spatially limited structural distribution.In this sense, a further process step of the evaluation unit may preferably at least comprise identifying the above-mentioned local differences in the structural distribution by dividing the image to be analyzed into a plurality of evaluation areas and, in order to include the previously described circumstances in the determination of the degree of condition, evaluating the individual evaluation areas at least independently of one another.
[0050] In a further preferred embodiment, the evaluation unit can also be configured to initially compare the images to be analyzed with previous protective glass states, similar to the intensity value analysis already mentioned above, before locating the individual protective glass structures. For this purpose, the latter image can preferably first be compared, for example, with a predefined image which, under the same optical conditions, can show an optimal protective glass state, so that possible signal values unrelated to the structures to be identified, such as intensity gradients or background signals generated by the settings of the analysis device, can be effectively excluded from the further analysis steps.Accordingly, it may preferably be possible for the evaluation unit, before a respective structure localization step, to first convert the image to be analyzed, for example, into a difference image based on subtracting the pixel intensity values of the optimal image from the image to be analyzed, and thus to further increase the evaluation precision of the previously described state degree calculation.
[0051] Furthermore, as already described above, the condition degree calculation itself can preferably be carried out after the respective object plane has been measured by the optical sensor device. The information thus obtained, be it the calculated condition degree or any protective glass properties derived from the images, can be stored in the storage device after analysis by the evaluation unit. Subsequently, it may be equally possible to use the above-mentioned process sequence to create a condition history of one or more existing protective glass units in the storage device. This history, in addition to the advantage of re-utilizing any data, for example, for the aforementioned differential image calculation, can also be used to predict future protective glass properties.
[0052] Thus, in a further preferred embodiment, the analysis device can be configured to determine the contamination, damage, and / or aging state of at least one protective glass, in particular continuously or at predefined time intervals, whereby a precisely defined series of measurements from determined data regarding the contamination, damage, and / or aging state can be generated and stored in the storage device for the analysis of further protective glass parameters. The series of measurements can preferably be temporal profiles, such as the changes in the protective glass condition or the degree of condition recorded per unit of time, as well as any properties of the system present around the protective glass, e.g.manufacturing steps carried out over time, recorded temperatures or mechanical / optical influences on the protective glass, so that, depending on the circumstances within the respective manufacturing plant, a specific data library tailored to the manufacturing plant can be created.
[0053] In this respect, the analysis device can preferably be configured, in particular, to utilize the above-mentioned measurement series from past analysis processes within this data library to generate assessments regarding preferred procedures with regard to the current protective glass condition. For example, in a preferred case, the analysis device can be configured to compare existing measurement series, in particular measurement series recorded under the same or similar manufacturing conditions, with the currently calculated protective glass conditions or condition levels and, for example, by extrapolating the condition level curves identified in the measurement series, to calculate a remaining service life of at least one protective glass based on these past measurement series.Alternatively, other parameters, such as a preferred time until cleaning, repair or replacement of a protective glass is required, can also be determined, preferably in addition to the service life.
[0054] It can be seen below that with the aid of the above-mentioned and claimed analysis device, a wide range of preferred advantages can be generated compared to conventional protective glass analysis devices of the prior art, which, due to the device elements of the analysis device which can be integrated simply and efficiently into existing production plants, can be introduced extremely effectively into preferably any type of production plant based on optical interactions.
[0055] In the following, a manufacturing system based on the exposure of workpiece materials and / or workpiece elements is also claimed, which equally has the above-mentioned advantages and is thus to be distinguished from conventional manufacturing systems.
[0056] The claimed manufacturing system can at least equally comprise one or a plurality of manufacturing systems based on optical interactions, according to the definition described above, as well as one or more embodiments of the analysis device already defined above and implemented in the manufacturing system. In this respect, the manufacturing system of the claimed manufacturing system can initially be regarded equally as at least one device comprising at least one light source for processing the said workpiece materials and / or workpiece elements, one or more light paths generated by the light source and used to illuminate the workpiece, and one or more protective glasses arranged to protect the light source from possible damage and / or contamination, and can thus preferably be identified with any conventional optical manufacturing system.
[0057] In a preferred embodiment, however, the corresponding manufacturing facility of the manufacturing system can also be configured in particular to be usable at least for the additive manufacturing of workpieces, such as by means of selective laser melting (“Selective Laser Melting” - SLM).
[0058] In particular, the optical interaction-based manufacturing system can preferably comprise at least one process chamber for this purpose, into which the workpiece materials and / or workpiece elements required for workpiece production can be introduced and processed by exposure using the light source. The process chamber itself can preferably be designed to be completely sealable, particularly in order to be able to meet the atmospheric conditions required for the SLM process, and in particular can be equipped with a number of chemical and / or mechanical control elements that enable the process chamber of the manufacturing system to dynamically adjust the pressure or the chemical components of the atmosphere existing within the process chamber during any manufacturing processes, thereby enabling an extremely stable and error-free manufacturing process to be realized.Specifically, the process chamber may, for example, also comprise various inlet and outlet valves for the introduction of required process chemicals, such as argon, and may at least be configured to hermetically seal the production space defined within the process chamber so that the above-mentioned conditions are met at all times.
[0059] In a preferred embodiment, the one or more protective glasses of the production system can also be part of the process chamber. For example, it may be possible for the at least one protective glass to be integrated into the housing of the process chamber or at least to be formed in contact with the latter housing, so that the at least one light source can guide the manufacturing light path(s) emanating from it through the protective glass and / or the protective glasses into the process chamber. Accordingly, the structure of the production system can also be configured at least in such a way that the light source can guide a light beam emanating from it through the at least one protective glass directly or via any preferably controllable optical elements, and thus allow it to strike the workpiece material and / or element to be processed.
[0060] The at least one light source itself can, as already mentioned, preferably be designed as a radiation source, such as a laser, designed for plastically deforming the workpiece elements. It can preferably be capable of moving and / or focusing the light path generated by the light source, preferably in any three-dimensional direction, via controllable optical elements (lenses, filters, mirrors, condensers, etc.) integrated into the radiation source or positioned externally. Further alignments of the beam system thus generated can also be achieved mechanically, for example by moving one or more exposure housings containing the optical elements and / or the light source of the production system, so that the material can be focused both mechanically and optically.
[0061] The at least one analysis device of the manufacturing system can, however, as described, be designed to be integrated into the manufacturing facility of the manufacturing system, preferably in one of the free spaces existing in the manufacturing facility. Thus, for example, in the present manufacturing system, the at least one analysis device can preferably be positioned at least between the light source or the exposure housing enclosing the light source and / or the optical elements of the light source and the above-mentioned process chamber, so that the analysis device can be designed, in particular, as a unit to be inserted between these two elements. In a particularly preferred embodiment, the at least one analysis device can also be positioned between a plurality of light sources or exposure housings and the process chamber.
[0062] The various device elements of the one or more analysis devices, but at least the optical sensor device, can furthermore, analogously to the embodiments described above, equally preferably be positioned between the process chamber and the at least one light source of the manufacturing system and, for example, be enclosed by the protective housing of the analysis device.
[0063] The specific position of the exposure device of a respective analysis device can also preferably vary depending on the preferred type of exposure: For example, in the case of a preferred incident light exposure, as described, the exposure device can preferably be attached along the side of a protective glass to be analyzed that faces the optical sensor device, so that it is possible to position both the optical sensor device and the exposure device in a common space, for example the protective housing of the respective analysis device. In the case of transmitted light illumination, on the other hand, the exposure device can preferably be positioned on the other side of the aforementioned protective glass or the introduced protective glasses, for example in a separate space within the process chamber, which makes it possible, in particular, to also protect the surfaces that are free from any contamination orTo directly expose the side of the at least one protective glass to be detected that is affected by damage. As a third preferred embodiment, it may also be possible, in particular in order to equally realize the most uniform possible illumination emanating from the side of a respective protective glass, for the exposure device to be incorporated into the structure of the process chamber, for example, into the housing or its outer wall, thus achieving not only an extremely space-saving but also equally stable integration of the exposure device.
[0064] Further advantages of the manufacturing system can also arise from possible interactions between the manufacturing facility and the at least one integrated analysis device. Specifically, the analysis device can, for example, be configured to exchange processing and / or process signals with the optically interacting manufacturing facility, so that corresponding analysis processes of the one or more analysis devices can be efficiently coordinated with existing production steps of the manufacturing facility.Accordingly, the at least one analysis device can be configured, for example, to receive at least information relating to existing work processes of the production plant and / or to send it back to the plant, so that the determination of the contamination, damage, and / or aging state of the at least one protective glass panel carried out by the analysis device can be carried out, in particular, automatically, after predefined production processes, for example before the start or after the end of workpiece production or during predefined waiting times. Conversely, however, the production plant can also be configured to adapt its production process to the designs of the analysis device(s) based on information received from the analysis device, thereby enabling an extremely efficient and, in particular, dynamic interaction of a respective analysis device with the existing production processes of the production plant.
[0065] Accordingly, it may be possible, for example, for the production plant to receive information regarding the current state of a protective glass implemented in the production plant regularly, for example at predefined intervals, through the at least one analysis device and to dynamically align the current and / or a future production process according to the above-mentioned information. For example, the production plant can preferably be configured to avoid any light paths potentially interacting with the detected problem after receiving a negative protective glass assessment (for example, after detecting a local burn or a crack).by changing the light path geometries used) or automatically redistributing a current processing process to other light sources or light paths unaffected by the previously described problem, so that a permanently constant processing quality can be ensured even during an ongoing production process. Analogous to the above-mentioned or general device elements, individual production steps and / or process parameters, such as the intensity or diameter of the producing light beam, can also preferably be adjusted based on individual information generated by the at least one analysis device, thereby achieving maximum adaptability of the production system with regard to occurring protective glass conditions.
[0066] Further interaction steps between a respective analysis device and the production plant can also preferably be designed in such a way that, in particular, the accuracy and comparability of the information generated by the analysis device can be optimized as best as possible, for example in order to allow an assessment that is as error-free as possible in the above-mentioned comparison of images of current protective glass states and those of an optimal protective glass state.For this purpose, the manufacturing system can be configured in particular to carry out the analyses carried out by the at least one analysis device at least under constant, identical conditions prevailing in the manufacturing system, such as existing background lighting, workpiece positions or manufacturing process times, which reduces any interference signals within the recorded images to a minimum, in particular after generation of the previously described difference images.
[0067] In order to avoid, in particular, the backlighting of the protective glass generated by the light source or within the process chamber of the production system, the production system can preferably also be configured to detect the respective protective glass object plane using an optical sensor device only when the light source is switched off or covered. In this respect, a process step of the production system preceding the analysis by the at least one analysis device can at least comprise switching off and / or covering the light source or any other light-emitting objects, in order, in particular, to enable consistent optical conditions incident on the optical sensor device.
[0068] In a particularly preferred embodiment, the production system can also comprise further device elements for the above-mentioned purpose, such as a flap or sliding element mounted in the production facility for shielding one or a plurality of analysis devices, or at least their optical sensor devices, from light emanating from the production facility. Specifically, this flap or sliding element can be designed, for example, as an object that can be moved or pivoted in at least one direction and is, if possible, non-reflective or highly absorbent, such as a black anodized plate or an optical filter element, which can be moved in front of the respective analysis device, the at least one protective glass, or the optical device, thus allowing, in particular, interfering light paths normally detected by the optical sensor devices to be separated from the latter.Accordingly, the flap or sliding element can preferably be designed to be movable at least from a first position for shielding said at least one analysis device to a second position for re-exposure of said analysis device at least from the side of the process chamber and / or the light source and back, whereby both the above-mentioned constant condition during detection by the analysis device and the re-opening of any light paths closed by the flap or sliding element for the general manufacturing process can be realized. Preferred positions of the flap or sliding element can also preferably be selected depending on the respective exposure type of the exposure device, but include at least the positioning of the flap or sliding element in the process chamber or the analysis device.
[0069] The respective process sequences carried out to determine the contamination and / or damage status of the at least one protective glass in the production facility of the production system can furthermore preferably be similar to those of the previously described functions of the aforementioned analysis device. Accordingly, the process steps equally claimed here and generated by the at least one analysis device of the present invention can comprise at least one of the following steps: - Detecting an object plane of the protective glass of the production plant by an optical sensor device; - Exposing the object plane using an exposure device; - evaluating information obtained by detecting the object plane of the protective glass by an evaluation unit, wherein the evaluation of the information comprises at least the analysis of detected light intensity values; - Detecting the condition, in particular the state of contamination, damage and / or aging, of at least one protective glass by the analysis device between predefined production processes of the production plant; - Determining a degree of contamination, damage and / or aging of a protective glass by comparing the information obtained by detecting the object plane by the optical sensor device with predefined reference information, such as limit values; - Determining service lives of the at least one protective glass used on the basis of a plurality of information determined by the at least one analysis device regarding the contamination and / or damage state of the protective glass. Short description of the characters Fig. 1: shows a two-dimensional view of a manufacturing system based on optical interactions, specifically an SLM system; Fig. 2: shows a two-dimensional view of a manufacturing system of the present invention; Fig. 3A: shows a detailed view of a first embodiment of the analysis device in a vertical cross-section, in which the exposure devices are positioned within the protective housing of the analysis device; Fig. 3B: shows the embodiment of the Fig. 3A as a detailed view in a horizontal cross-section; Fig. 4A: shows a detailed view of a second embodiment of the analysis device in a vertical cross-section, in which the exposure devices are positioned in the process chamber; Fig. 4B: shows the embodiment of the Fig. 4A as a detailed view in a horizontal cross-section; Fig. 5A: shows a detailed view of a third embodiment of the analysis device in a vertical cross-section, in which the exposure devices are integrated into the structure of the process chamber; Fig. 5B: shows the embodiment of the Fig. 5A as a detailed view in a horizontal cross-section; Fig. 6A: shows the detailed view of the analysis device of the Fig. 3A, wherein a movable flap or sliding element is additionally arranged within the process chamber; Fig. 6B: shows the embodiment of the Fig. 6A as a detailed view in a horizontal cross-section; Fig. 7A shows another embodiment of the analysis device in which the protective glass is analyzed by several independent sensor devices; Fig. 7B shows the embodiment of the Fig. 7A as a detailed view in a horizontal cross-section; Fig. 8A shows another embodiment of the analysis device in which the sensor device is arranged coaxially with the protective glass; Fig. 8B shows the embodiment of the Fig. 8A as a detailed view in a horizontal cross-section; Fig. 9A shows a further embodiment of the analysis device in which an additional mirror element is arranged in the analysis device for coaxial analysis of the protective glass; Fig. 9B shows the embodiment of the Fig. 9A as a detailed view in a horizontal cross-section. Detailed description of preferred embodiments
[0070] In the following, exemplary embodiments of the present invention are described in detail with reference to exemplary figures. The features of the exemplary embodiments can be combined in whole or in part, and the present invention is not limited to the described exemplary embodiments.
[0071] Fig. 1 shows a schematic embodiment of a manufacturing plant 1 based on optical interactions, specifically a manufacturing plant for selective laser melting in which a material 18 to be processed is applied layer by layer on a movable base plate 16 and is locally remelted by means of focused laser irradiation in such a way that a three-dimensional workpiece 26 can be generated by continuously applying, exposing and fusing further material layers 24 (additive manufacturing).
[0072] For this purpose, the production system 1 provides at least one (laser) light source 4, which, via a control system 6 coupled to the production system 1, generates a light beam modified for interaction with the material layers 24. This light beam is focused via a light path 14 onto the material layer to be processed with the aid of various optical elements integrated in a scan head 2, such as focus or scattering lenses, mirrors, optical filters, etc. The scan head 2 itself is in this case a standalone, rigid housing, in which the latter optical elements are aligned in a manner that can be controlled manually and / or automatically, and thus generate a three-dimensionally positionable light path 14 depending on their current orientation and the optical properties assigned to them (e.g., focus lengths or filter frequencies).
[0073] In order to also ensure suitable protection of the optical elements described above from any process emissions, the scan head 2 in the present embodiment is initially designed as a closed or lockable system in which the light path 14 can only be led out of the scan head 2 through an exit hole provided with a scan head glass 3. In further embodiments, however, it may also be possible to design the optical elements as a freestanding device system or to integrate the latter at least partially into other units of the production system 1, such as the light source 4. The representation of the light source 4 in this case also serves only visual purposes, so that the latter can equally be integrated into the scan head 2 or other elements of the production system 1.
[0074] Due to the above-mentioned working distances of the optical elements implemented in the scan head 2, the light path 14 used to manufacture the workpiece 26 also leads through the scan head glass 3 into a process chamber 12 spaced from the scan head 2 by a free space 5, in which process chamber the various material layers 24 to be processed are applied to a movable base plate 16 and focused by the producing light beam to produce the workpiece 26. The precise manufacturing process, as described above, provides for an iterative coating and exposure process: To manufacture any three-dimensional workpiece 26, the material to be processed is first applied in powder form in a thin layer 24 to a base plate 16 and by at least vertically moving the base plate 16 by means of controllable lifting devices 20 (e.g.pneumatic, electrical or mechanical cylinder or scissor lifting devices) to a processing height corresponding to the light path 14. In order to guarantee a material layer 24 that is as uniform and, in particular, dense as possible, the corresponding powdered material 18 in this exemplary embodiment is also previously compacted with at least one roller 22 that can be moved parallel to the material layer 24 being processed (alternatively with further devices such as integrated silicone lips), brought to a predefined layer height, and excess material 18 is removed from the base plate 16, so that, in particular, consistent material conditions can be ensured within each iteration process.
[0075] The processed powdered material layer 24 is then locally remelted using the aforementioned light beam focused through the light path 14, and after solidification, forms a solid material layer. Subsequently, the base plate 16 is lowered by a predefined layer thickness of the material layer 24, and a new material layer 24 is applied to the base plate 16, so that, through repeated processing and the addition of new material layers 24, a fused, three-dimensional material shape (the workpiece) 26 can be formed.
[0076] In order to enable the atmospheric conditions suitable for the above-mentioned SLM manufacturing process, the process chamber 12 of the manufacturing plant 1 is further designed as a completely closable processing housing equipped with any regulatory elements, such as pressure regulators or valves for the introduction or removal of required processing chemicals (e.g. argon, neon, etc.), which housing in particular completely encloses the above-mentioned base plate 16 by integration into the process chamber structure 11 (i.e. at least the process chamber outer wall) and can thus provide a manufacturing area sealed off from external influences.In order to also enable the contact of the light path 14 with the various material layers 24, a protective glass 10 is also introduced into the process chamber housing 11, which, due to its optical properties, is at least designed to allow the light beam emanating from the light source 4 or controlled by the scan head 2 into the process chamber 12 and to shield the elements of the production system 1 mounted in the scan head 2 or otherwise from any process emissions 28 (powder residues, smoke, sparks, etc.) that may occur during production.
[0077] Accordingly, as already mentioned above, the problem arises in conventional manufacturing systems 1 based on optical interactions according to the state of the art that due to the simultaneous protective and transmission function of the protective glass 10 introduced into the process chamber 12, the manufacturing quality of the manufacturing system 1 can deteriorate noticeably due to emission particles 28 accumulating on the protective glass 10 (and thus interacting with the manufacturing light path 14).On the other hand, however, in most cases, any cleaning and / or replacement processes involving the protective glass 10 are associated with extremely high costs and downtimes of the production facility 1, so it is of utmost importance for current production facilities 1 to implement a method for identifying any (contamination and / or damage) conditions and thus generate the most accurate information possible about the required maintenance measures. For this purpose, the analysis device D of the present invention is proposed.
[0078] Fig. 2 shows a first schematic representation of the production system of the present invention, in which the analysis device D is integrated into the production plant 1 of the Fig. 1 is shown integrated. As can be seen, the analysis device D is specifically designed to be implemented in the free space 5 required by the optical properties of the production system 1, whereby the latter is positioned in particular directly along the light path 14 and is preferably detachably connected to both the scan head 2 and the process chamber 12 of the production system. In this respect, this embodiment of the production system has the advantage that, by utilizing already existing free spaces within the production system 1, no further (for example, optical) adjustments to the production system 1 are necessary during the implementation of the analysis device D, whereby the analysis device D can thus be extremely easily and efficiently integrated into an existing production process.
[0079] Fig. 3A and Fig. 3B also show a schematic detailed representation of a first embodiment of the Fig. 2 and integrated into the production system 1, each in a horizontal and a vertical cross-section. As mentioned above, the analysis device D in this case is implemented in the free space 5 between the scan head 2 and the process chamber 12 and thus requires only unused areas of the production system 1 for analyzing the protective glass condition. The analysis device D itself comprises at least the optical sensor device S, which is designed as an imaging sensor provided with optics (focus lenses, mirrors, filters, condensers, etc.), in any case also as any camera device, as well as a plurality of exposure devices L1 - L4 for exposing the protective glass 10 to be analyzed by the optical sensor device S.In order to further shield the above-mentioned device elements of the analysis device D from external influences, such as dust or harmful light exposures, the optical sensor device S and the exposure devices L1 - L4 are additionally arranged in a protective housing 7 of the analysis device D, for example, which is tubular in shape. The outer wall of the housing is connected to both the scan head 2 and the outer process chamber structure 11, thus forming a closed system enabled by this connection. Furthermore, by positioning the protective housing 7, the outward-facing side of the scan head glass 3 and the protective glass 10 of the process chamber 12 are equally integrated into the area enclosed by the analysis device D, whereby these elements can also be additionally protected by the implementation of the analysis device D.
[0080] The exact positioning of the optical sensor device S and / or the exposure devices L1 - L4 of the analysis device D can also vary depending on the structure of the production plant 1 to be analyzed, but is in the Fig. 3A or 3B, the optical sensor device S is arranged above the exposure devices L1 - L4, for example, on the inside of the protective housing 7, and thus enables a problem-free continuation of any manufacturing processes due to a possible positioning outside the light path 14 generated by the light source 2. The exposure devices L1 - L4 used to expose the protective glass 10 are furthermore arranged at regular intervals, for example, symmetrically (see Fig. 3B), positioned within the protective housing 7 and similarly oriented such that the protective glass surface exposed in any manufacturing processes of the production plant 1 is not impaired in any way. In this respect, the implementation of the above-mentioned device elements defined by the analysis device D can, in particular, generate a device system that enables both efficient and extremely precise detection of the protective glass condition to be analyzed and, through the interaction-free positioning of the latter elements, allows for a simple protective glass evaluation that can be implemented in any manufacturing process.
[0081] The evaluation process of the protective glass 10 carried out by the analysis device D also takes place in the Fig. 3A and Fig. 3B by evaluating the incident light images generated by the optical sensor device S: The optical elements of the optical sensor device S used for focusing and adjustment as well as the exposure devices L1 - L4 and / or the general alignment of the latter device elements are first oriented in such a way that a specific plane, the object plane 30 (see Fig. 3B), of the protective glass 10 is focused by the optical sensor device S and exposed using the exposure devices L1 - L4, whereby any contamination, damage and / or aging structures 28 (material residues, smoke, scratches, bleaching, etc.) accumulated on the side of the protective glass 10 facing the process chamber 12 are uniformly illuminated from the outside of the process chamber 12 and the scattered light thus generated by the structures can be fed back to the imaging sensor of the optical sensor device S as a location-dependent signal.Accordingly, in the optical sensor device S, an at least one-dimensional signal, but in preferred cases in particular a two-dimensional image of the previously focused object plane 30 is generated, in which the respective contamination, damage and / or aging structures 28 located in the object plane and illuminated by the exposure devices L1 - L4 are represented as bodies equipped with comparatively high signal or intensity values and can thus be analyzed for further condition assessments.
[0082] The determination of the protective glass condition is carried out, as already mentioned above, by evaluating the information obtained in the generated image, specifically by calculating a degree of condition that is dependent on a plurality of imaging parameters and describes the quality condition of the protective glass 12, which degree of condition can be generated in the present invention either manually, e.g. by outputting and assessing the image by trained specialist personnel, or automatically on the basis of an evaluation unit (not shown) implemented in the analysis device D.Suitable examples of the above-mentioned imaging parameters can in particular be properties specifically related to the recorded structures 28, such as the number, size, shape or density of the contamination, damage and / or aging structures 28 located along the object plane 30 (and thus along the protective glass 10), but also parameters based on optical influences, such as the intensity values associated with the structures 28 within the image generated or to be analyzed, and thus allow the assessment of the protective glass condition, in particular depending on factors directly related to the contamination or damage.
[0083] To determine the properties described above, the evaluation unit of the analysis device D is also equipped with a series of image analysis and processing programs, which allow the evaluation unit, for example, to identify individual structural bodies within the generated image and to extract the desired parameters from them using various pixel segmentation and evaluation processes. Furthermore, to improve the identification of any structures, the evaluation unit can previously adapt the image to be analyzed using a variety of processing mechanisms, such as background corrections, edge filtering, and / or blur correction, or convert the former into another image format, for example by creating the previously described difference image, thereby making the analysis of the protective glass 10 even more precise.
[0084] In a final step, the evaluation unit is also set up to convert the above-mentioned imaging parameters into an easily understandable condition level, such as a percentage that decreases with the condition of the protective glass 10, a normative quality statement (e.g. "protective glass clean", "protective glass damaged", "protective glass dirty") or a suggested treatment step ("cleaning necessary", "replacement necessary", etc.), so that, by outputting the condition level by the analysis device D, selected specialist personnel can be quickly and effectively informed about the protective glass processing steps to be carried out. In the case of the above-mentioned statements orIn the proposed treatment steps, this can be done by comparing the identified imaging parameters with any limit values adapted to the parameters, so that the evaluation unit issues a request to clean or replace the respective protective glass 10, for example after a certain number, density or size of identified damage, contamination and / or aging structures has been exceeded. In the case of a plurality of imaging parameters to be integrated for calculating the degree of condition, the former can also initially be summarized via a previous combination step, for example through weighted and / or previously relativized averaging processes, so that in the present invention it is equally possible to include various parameters to be identified in the generated image for determining the protective glass condition.
[0085] Accordingly, the Fig. 3A and Fig. 3B, an integrable protective glass examination unit is provided which can be easily and extremely efficiently introduced into existing production plants 1 and can also determine the current state of the protective glass 10 to be analyzed by including primary parameters, ie parameters explicitly existing on the protective glass 10.
[0086] Fig. 4A and Fig. 4C also show a further embodiment of the previously described analysis device D, in which, instead of the Fig. 3A and Fig. 3B, a transmitted light illumination is implemented for identifying any contamination, damage, and / or aging structures 28. Compared to the previously described embodiment, the analysis device D of these figures differs in particular in the positions of the exposure devices L6-L9 used to illuminate the protective glass 10, which in this example are mounted within the process chamber 12 and thus on the other side of the protective glass 10 compared to the optical sensor device S.
[0087] In this respect, the exposure devices L6 - L9 of this exemplary embodiment are set up to detect the particles 28 located on the protective glass 10 by the optical sensor device S, illuminating the protective glass 10 in particular from the wetted / soiled side, whereby a large part of the light emanating from the exposure devices L6 - L9 equally passes through the protective glass 10 into the beam path of the optical sensor device S and is only reflected or scattered at points containing particles 28. Accordingly, within the image generated by the optical sensor device S in this case, an image is produced which is the opposite of the previous embodiment, in which unaffected portions of the detected protective glass 10 are shown as signal orhigh-intensity background, however, positions associated with respective contamination, damage, and / or aging structures 28 are represented as low-signal bodies. Consequently, in this exemplary embodiment, the condition of the protective glass 10 to be analyzed can also be effectively determined by the aforementioned calculation of the degree of condition, since the analysis device D in this case also realizes a spatially resolved representation of any contamination, damage, and / or aging structures 28.
[0088] Fig. 5A and Fig. 5B also shows a further embodiment of the present analysis device D, in which the exposure device L5, in contrast to the previous examples, is shown integrated into the process chamber housing 11 and thus allows the protective glass 10 to be uniformly illuminated, in particular from the outside of the protective glass radially inward, by an exposure beam 32 oriented parallel to the protective glass 10. For this purpose, the exposure device L5 in this case is designed as an integrated illumination ring (which preferably completely encloses the protective glass laterally) around the protective glass 10, which is also shown as circular, but can also be present in other embodiments in other geometries, in particular adapted to the structure of the protective glass 10.In this respect, such an integrated design of the exposure device L5 into the production system 1 offers the advantages that the latter device element can be incorporated extremely efficiently and in a space-saving manner within the production system, while the aforementioned type of exposure equally allows an evaluation of the protective glass according to the aforementioned image analysis and condition degree calculation process. Furthermore, there is the positive effect that the lateral exposure of the protective glass 10 (lateral scattering of light into the protective glass, in particular via LEDs arranged in a ring shape) illuminates both the side of the protective glass 10 facing the process chamber 12 and the analysis device D from the inside, thereby effectively preventing any error-generating processes, such as back reflections, on the outer sides of the protective glass.
[0089] Fig. 6A and Fig. 6B also show again the embodiment of the Fig. 3A and Fig. 3B, in which, in addition to the exposure devices L1 - L4 and the optical sensor device S, a flap or sliding element 36, shown here as a black-anodized and thus reflection-free plate, which can be moved along the longitudinal axis of the protective glass 10, has been inserted into the process chamber 12. The flap or sliding element 36 comprises, in particular, a controllable movement mechanism 34 (e.g., a pneumatic, electrical, or mechanical motor element) which is coupled to the production process of the production system 1 and which allows the flap or sliding element 36 to move parallel to the alignment of the protective glass 10 at least from a first position for shielding the protective glass 10 from any exposure sources located in the process chamber 12 to a second position for re-opening the light path 14 between the scan head 2 and the process chamber 12 and back.Accordingly, the flap or sliding element 36, which is additionally implemented in the production system 1, can prevent any light emanating from the process chamber 12 and also penetrating the analysis device D in the first position. This efficiently blocks any interfering background signals, especially for the image capture of the aforementioned object plane 30 by the optical sensor device S, and thus realizes far more consistent conditions for the aforementioned recordings. In this respect, the protective glass evaluation process carried out by the analysis device D is as described in the . Fig. 6A and Fig. 6B, the embodiment shown also at least additionally provides for moving the flap or sliding element 36 into the first position whenever the protective glass 10 is to be examined by the analysis device D, and returning the flap or sliding element to the second position when the light path 14 defined by the protective glass 10 should be left open, for example, for the production of a workpiece 26 by the production system 1. As a result, an improvement of the protective glass analysis process can also be made possible in this case without having to modify and / or adjust existing production mechanisms of the aforementioned production system 1.
[0090] The Fig. 7A and Fig. 7B also shows a further detailed representation of an embodiment of the claimed manufacturing system, in which the present manufacturing system 1, in comparison to the previous embodiments, is equipped with a plurality of scanning heads 2A & 2B and protective glasses 10A & 10B and is consequently capable of processing one or a plurality of workpieces 26 to be manufactured using preferably independently controllable light paths 14. In order to enable the most accurate detection and evaluation of the introduced protective glasses 10A & 10B even in such multi-scanner systems, in the present embodiment, a plurality (in this case two) of analysis devices D1 & D2 adapted to the number of protective glasses 10A & 10B are likewise introduced into the manufacturing system 1, so that each of the implemented protective glasses 10A & 10B can preferably be individually analyzed and checked to improve any manufacturing processes.The analysis devices D1 & D2 themselves are located in the . Fig. 7A and Fig. 7B, analogous to the previous embodiments, positioned between one of the respective scanning heads 2A & 2B and one of the shown protective glasses 10A & 10B and have, as in the example already shown in Fig. 3A and Fig. 3B, a plurality of exposure devices L10-L17 and at least one sensor device S1 & S2 are provided in each case to precisely expose any contamination, damage, and / or aging structures 28 occurring on the protective glass 10A & 10B assigned to them and to detect and analyze them using the detection mechanisms already mentioned above. Furthermore, the analysis devices D1 & D2 in this case are each equally equipped with a protective housing 7A & 7B formed at least laterally of the aforementioned device elements and separating the interior of the analysis device D1 & D2, which can both individually protect the latter from any process emissions (dust particles, smoke, etc.) and maintain existing protective glass analysis conditions constant, for example, by blocking certain background radiation also generated by the respective other analysis device D1 & D2.
[0091] Accordingly, the exemplary embodiment shown demonstrates that the present invention can also be optimally used in a production plant characterized by multiple scanning heads 2A & 2B, protective glass 10A & 10B, or other devices required for workpiece production, in particular since a plurality of individually acting and independently positionable analysis devices D1 & D2 can be integrated for this purpose, at least to the same extent. In this respect, the above-mentioned embodiment offers the particular advantage that each protective glass 10A & 10B implemented in the production plant 1 can also be analyzed and subsequently assessed by an analysis device D1 & D2 directed solely at this protective glass 10A & 10B, thereby enabling extremely precise condition detection.
[0092] The Fig. 8A and Fig. 8B also show a further embodiment of the claimed analysis devices D, in which the production plant 1 is equipped analogously with a plurality of scanning heads 2A - 2C as well as with the scanning head glasses 3A - 3C connected thereto and required for forwarding the light beam 14 emanating from the scanning heads 2A - 2C, and the analysis device 1 comprises an exposure device L5 according to the embodiment of Fig. 5A and Fig. 5B. In this case, the scan head glasses 3A - 3C themselves are incorporated in an independent base plate 34 that is (at least thermally) decoupled from the analysis device D and / or the scan heads 2A - 2C, which makes it possible, in particular, to prevent any displacements / relocations of the scan heads 2A - 2C or the device elements of the analysis device D due to expansions within the production system 1 that occur during production and are based at least on thermal fluctuations, thereby ensuring a consistently accurate and thus less prone to errors machining or analysis process.
[0093] Fig. 8B further shows a schematic plan view of the inside of the previously described base plate 34, shown along the viewing plane A. Here, the scan head glasses 3A - 3C are shown as circular components, but in other cases can also be identified by other geometries and have possible optical properties (e.g., wavelength-specific absorptions / reflections), which are positioned concentrically at predefined intervals, preferably, for example, around a predetermined point, and thus enable processing of the workpiece 26 to be manufactured by a plurality of light beams or distinguishable light paths. In this case, the sensor device S is also mounted in the center of the concentrically arranged scan head glasses 3A - 3C, which, due to its central positioning, which is preferably aligned equally with the protective glass 10, both generates a maximum detection area and, due to the Fig. 8A, an extremely space-saving integration can be realized. Furthermore, this arrangement makes it possible to align the sensor device S, in particular coaxially with the respective protective glass 10 present (e.g., the longitudinal axis of the sensor device S is parallel to at least one longitudinal axis of the protective glass 10), so that the image plane to be captured can coincide with the protective glass surface 28 affected by damage, contamination and / or aging structures (in particular the inner side of the protective glass 10 present in the process chamber 12) simply by suitable mechanical alignment of the sensor device S.Accordingly, the above-mentioned arrangement of the sensor device S and the exposure device L5 primarily generates an embodiment of the analysis device D which not only realizes the most space-saving positioning of the respective device elements, but equally also enables an optically preferred alignment of the optical sensor device S.
[0094] As an alternative to the last-described embodiment, the aforementioned coaxial alignment of the sensor device S can also be realized by additional optical elements, such as a fully or semi-transparent mirror. For this purpose, the Fig. 9A and Fig. 9B shows an example of a further embodiment of the Fig. 8A and Fig.8B, in which the sensor device S, contrary to the aforementioned central positioning, is inserted laterally, for example in the structure of the protective housing 7, and can coaxially receive the scattered and reflected radiation emanating from the structures 28 of the protective glass 10 to be detected via a further mirror device 36 additionally mounted in the analysis device D. The advantage of the embodiment shown here can be seen in particular in the extremely space-saving introduction of the required device elements, since the additional implementation of the mirror device 36 allows the sensor device S, although still optically coaxially connected to the protective glass 10, to be potentially integrated at any desired position within the analysis device D, so that the analysis device D can also be installed in particularly small installation spaces.Furthermore, it may preferably also be possible to design the mirror device 36 in particular in such a way that its orientation can be dynamically adapted at any time to the current position or arrangement of a selected sensor device S, so that with the aid of the first-mentioned device not only the position of the corresponding sensor device S within the analysis device D can be freely selected, but also several sensor devices S can be used by means of the mirror device 36.
Claims
[1] Analysis device (D) for determining and / or monitoring a condition, in particular a condition of contamination, damage and / or aging, of at least one protective glass (10) of a production plant (1) based on optical interaction, wherein the protective glass (10) is provided for protecting a light source (4) configured for producing a workpiece (26) and optical elements of the production plant (1); wherein the analysis device (D) comprises: - at least one optical sensor device (S) for detecting an object plane (30) associated with the protective glass (10) of the optical manufacturing system (1); wherein the analysis device (D) is designed to be integrable into the production plant (1) and is configured to be positioned in the region of or along a light path (14) of the light source (4); the optical sensor device (S) is configured to be arranged between the light source (4) and the protective glass (10) of the production plant (1) and / or at a distance from the protective glass (10), on the side of the protective glass (10) facing the light source (4); and wherein the optical sensor device (S) comprises an imaging sensor element; and the imaging sensor element is configured to generate an at least one-dimensional image of the detected object plane (30) of the protective glass (10). [2] Analysis device (D; D1; D2) according to claim 1, wherein the analysis device (D; D1; D2) additionally comprises at least one exposure device (L1 - L17) for exposing the object plane. [3] Analysis device (D; D1, D2) according to at least one of the preceding claims, wherein the analysis device (D; D1; D2) comprises a protective housing (7; 7A; 7B) into which the optical sensor device (S; S1, S2) and / or the exposure device (L1 - L4; L10 - L17) are integrated; and the protective housing (7; 7A; 7B) is designed to enclose the optical sensor device (S; S1; S2) and / or the exposure device (L1 - L4; L10 - L17) at least laterally. [4] Analysis device (D) according to at least one of the preceding claims, wherein the analysis device (D) additionally comprises at least one evaluation unit for evaluating information obtained by detecting the object plane (30) using the optical sensor device (S); wherein the evaluation unit is connected to a storage device for obtaining additional information; and the evaluation unit is configured to extract reference information from the storage device in order to determine the state of contamination, damage and / or aging of the protective glass (10) and to compare the information obtained by the optical sensor device (S) with the reference information of the storage device and, depending on the differences in the compared information, to determine a degree of damage, contamination or aging. [5] Analysis device (D) according to at least claim 4, wherein the information obtained by the optical sensor device (S) comprises at least intensity values of an image recorded by the optical sensor device (S); the intensity values can be assigned to individual pixel positions of the recorded image; and the evaluation unit is configured to identify damage, contamination and / or aging structures within the image using intensity values of the recorded image. [6] Analysis device (D) according to at least one of the preceding claims, wherein the analysis device (D) is designed to determine the damage, contamination and / or aging state of the protective glass (10) continuously or at predefined time intervals; and to at least partially use a series of measurements of determined data regarding the state of damage, contamination and / or aging of the protective glass (10) in order to determine a remaining service life of the protective glass (10). [7] Manufacturing system for manufacturing a workpiece (26) by exposing workpiece material (18) and / or workpiece elements, comprising: - a manufacturing system (1) based on optical interaction, comprising at least one light source (4) for processing the workpiece materials (18) and / or workpiece elements, at least one light path (14) generated by the light source (4), and one or more protective glasses (10) for protecting at least the light source (4) from damage and / or contamination; and - at least one analysis device (D) according to at least one of the preceding claims, which is integrated into the production plant (1). [8] Manufacturing system according to claim 7, wherein the optical interaction-based manufacturing system (1) additionally comprises a process chamber (12) in which the workpiece (26) is manufactured by exposure using the light source (4); wherein the at least one protective glass (10) is integrated into the housing of the process chamber (12), and the analysis device (D) is arranged such that the light source (4) can guide the generated light path (14) through the analysis device (D) into the process chamber (12). [9] Manufacturing system according to at least one of claims 7 and 8, wherein the exposure device (L5) of the at least one analysis device (D) is integrated into the housing of the process chamber (12) such that the protective glass (10) of the production plant (1) is illuminated from the side by the exposure device (L5), in particular by direct light irradiation into the side surfaces of the protective glass (10), and wherein the manufacturing system is in particular an SLM system. [10] Manufacturing system according to at least one of claims 7 to 9, wherein the analysis device (D) is designed to determine the contamination, damage and / or aging state of the protective glass (10) according to predefined manufacturing processes or process steps of the manufacturing plant (1), in particular in an automated manner, and / or wherein the analysis device (D) is configured to monitor the condition of the protective glass (10) during component production by the manufacturing plant (1). [11] Manufacturing system according to at least one of claims 7 to 10, wherein the production plant (1) additionally comprises at least one flap or sliding element (36) for shielding the analysis device (D) from exposures emanating from the production plant (1); wherein the flap or sliding element (36) is designed to be movable at least from a first position for shielding the analysis device (D) to a second position for exposing the analysis device (D) at least from the side of the process chamber (12) and back. [12] Method for determining a condition, in particular a condition of contamination, damage and / or aging, of at least one protective glass (10; 10A; 10B) of a manufacturing plant (1) based on optical interactions with at least one light source (4) configured to manufacture a workpiece (26) and a light path (14) generated by the light source (4), by an analysis device (D; D1; D2) according to at least one of claims 1 to 6, comprising: - detecting the object plane (30) associated with the at least one protective glass (10; 10A; 10B) of the production plant (1) by the optical sensor device (S; S1; S2); - exposing the object plane (30) by an exposure device (L1 - L17); - evaluating the information obtained by detecting the object plane (30) of the protective glass (10; 10A; 10B) by an evaluation unit, wherein the evaluation of the information comprises at least the analysis of detected intensity values. [13] The method according to claim 12 further comprising: - detecting the condition, in particular the state of damage, contamination and / or aging, of the protective glass (10; 10A; 10B) by the analysis device (D; D1; D2) between production processes of the production plant (1); - Determining a degree of damage, contamination or aging of the protective glass (10; 10A; 10B) by comparing the information obtained by detecting the object plane (30) by the optical sensor device (S; S1; S2) with predefined reference information; - Monitoring the condition of the at least one protective glass (10; 10A; 10B) and / or determining the service life of the protective glass (10; 10A; 10B) on the basis of a plurality of items of information determined by the analysis device (D; D1; D2) regarding the state of damage, contamination and / or aging of the protective glass (10; 10A; 10B).
Citation Information
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