Apparatus and method for inspecting object based on sensor

Abstract

The invention relates to a device for inspecting, in particular plate-shaped or strip-shaped, physical objects on the basis of sensors, comprising: a transport device for transporting the physical objects to be inspected along a transport path; an image sensing device having at least one image sensor for image-sensing detection of the object during a continuous movement of the object along the transport path relative to the image sensing device by the transport device; an illumination device for illuminating a surface to be inspected of the object in a wavelength range that can be detected by the image sensing means such that the image sensing means can detect the surface at least partially in the illuminated surface region by means of an image sensing technique; and a shielding device for shielding the image sensing mechanism from radiation not originating from the illumination device. The image sensor has N digital line scanning cameras, N > = 1, each having a plurality of camera pixels arranged in rows, the rows of the line scanning cameras each extending transversely, in particular orthogonally, to the transport path. The device or the method which can be carried out by the device can be used in particular for inspecting electrodes of galvanic cells or precursors thereof.

Description

Technical Field

[0001] The invention relates to a device and a method for the sensor-based inspection of physical objects, wherein in particular (at least macroscopically) substantially flat surfaces of the objects, for example the surfaces of plate-like or strip-like objects, can be inspected. The invention also relates to a specific application of the device and / or method for the inspection of electronic substrates of electrodes of galvanic cells or the coating of such electronic substrates with anodic or cathodic materials. Background Art

[0002] In the production or use of various physical objects (i.e. objects that take up space and mass), in particular intermediate or end products in industrial production processes, it is of great importance to ensure the high quality of the objects. In this case, the quality requirements may in particular relate to the integrity or purity of one or more surfaces of the object. An example of such an object is an electrode for a primary cell (e.g. a lithium-ion battery), which is used in a variety of electronic devices and in particular in the context of electric vehicles for the energy supply of vehicles (e.g. passenger vehicles) or for the intermediate storage of electrical energy in stationary devices. It is particularly important here that the electrodes are essentially free of contamination, since such contamination, in particular particulate contamination, in addition to reducing the performance of the primary cell, can also lead to electrical short circuits and thus to failures of the primary cell or even to dangerous situations.

[0003] In the known technical solution, the battery (which may have one or more galvanic cells) is checked as soon as it leaves the factory within the framework of the quality assurance process to determine whether an electrical short circuit exists. The check is performed statically, i.e. the battery to be checked is stationary relative to the test device used to perform the check. Summary of the invention

[0004] The object of the present invention is to provide an improved technical solution for quality control of physical objects, in particular electrodes of galvanic cells or preforms thereof.

[0005] The object of the invention is achieved by the teaching of the independent claim. Various embodiments and developments of the invention are given by the dependent claims.

[0006] The first aspect of the technical solution proposed here relates to a device for inspecting a physical object, in particular a plate-shaped or strip-shaped physical object, based on a sensor. The device comprises:

[0007] (i) a transport device, in particular having one or more conveyor belts, for transporting the physical objects to be inspected along a transport path;

[0008] (ii) an image sensor device having at least one image sensor for detecting the object at least partially by image sensing technology during its continuous, i.e. non-stop, but not necessarily constant, movement relative to the image sensor device along the transport path by the transport device;

[0009] (iii) an illumination device for illuminating any macroscopically planar surface of the object to be examined in a wavelength range detectable by the image sensor device, in particular in the visible range (VIS) of the electromagnetic spectrum, so that the image sensor device can at least partially detect the surface in the thus illuminated surface region by sensor technology; and

[0010] (iv) shielding means for shielding the image sensing means from radiation not originating from the illumination means, in particular radiation in said wavelength range.

[0011] In this case, the image sensor system has a number N (N≧1) of digital line scan cameras, each of which has a plurality of camera pixels arranged in rows, wherein the rows of the line scan cameras each extend transversely, in particular orthogonally, to the transport path.

[0012] The term "physical object" as used herein refers to an object that occupies space and has mass. Thus, in particular, an industrial product having mass is a physical object. This includes in particular electrodes of primary cells, in particular lithium-ion cells or lithium-ion rechargeable batteries, or precursors of such electrodes, membranes coated with catalysts, gas diffusion layers or membrane electrode assemblies (MEAs) as precursors for fuel cells.

[0013] The term "line scan camera" as used herein refers to an image sensor or camera of the digital camera type having a digital image resolution of M×K camera pixels, where (i) M≥1000·K and K≤256, and / or (ii) M>K, where K=1. In this context, M denotes the number of camera pixels per row and K denotes the number of rows. In particular, in contrast to a two-dimensional sensor having a plurality of rows, a line scan camera can therefore also have only one (K=1) radiation-sensitive row (row sensor). The camera pixels can each have a plurality of sub-pixels of different colors, for example according to the RGB color model or other color models.

[0014] As used herein, the terms "comprises," "including," "involving," "having," "having," "with," or any other variation thereof, shall encompass a non-exclusive inclusion. Thus, for example, a method or apparatus that comprises or has a list of elements is not necessarily limited to those elements but may include other elements not expressly listed or inherent to the method or apparatus.

[0015] In addition, unless otherwise expressly stated, "or" should be understood as an inclusive or, not an exclusive "or". For example, condition A or B satisfies one of the following conditions: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); and both A and B are true (or exist).

[0016] As used herein, the terms “a” or “an” should be understood as “one / one or more.” The terms “another” and “another” and any other variations thereof should be understood as “at least one other.”

[0017] The term "plurality" as used herein should be understood as "two or more".

[0018] The term "configured" or "designed" as used herein to fulfill a certain function (and its corresponding variants) is to be understood as meaning that the relevant device or its components already exist in an embodiment or setting that can perform this function, or that they are at least adjustable, i.e. configurable, so that they can perform this function after corresponding adjustments. The configuration can be carried out here, for example, by corresponding adjustments of process parameters or switches for activating or deactivating functions or adjustments. In particular, the device can include a plurality of preset configurations or operating modes, so that the configuration can be carried out by selecting one of these configurations or operating modes.

[0019] The device according to the technical solution allows the physical object to be inspected based on the sensor while being continuously transported by the transport device. The object therefore does not need to stop at a specific station and then move again, and since such a stop is eliminated during the inspection process, higher process efficiency can be achieved in a shorter operating time. In addition, if the object is a device, such as a primary cell or an entire battery pack with multiple such cells, the components of the device, especially the electrodes, can be inspected without the entire device being completed. On the contrary, the intermediate product can be inspected. If it is identified as defective here, it can be screened out before the device is completed. With regard to the mass production of such devices, the overall required material input can be reduced, because when a defect is identified, only the component identified as defective needs to be removed or repaired as scrap, rather than the completed device. Therefore, on the whole, the technical solution helps to identify errors in production as early and efficiently as possible and thus deal with quality defects.

[0020] However, the advantages are not only in terms of efficiency, in particular, special image sensor systems can also be used in combination with N-line scan cameras, lighting devices and shielding devices to achieve high image quality and resolution, so that very small disturbances, such as the smallest particles present on the surface to be inspected, can be detected particularly well. This is mainly because: line scan cameras can usually achieve a particularly high effective resolution; the lighting device provides good lighting conditions and in particular can also provide projections that can be well detected due to recognizable disturbances (especially particles present on the surface); the shielding device ensures that the image provided by the image sensor system is particularly low-noise, because interfering influences from radiation outside the lighting device are at least largely eliminated.

[0021] These advantages are particularly evident when using the device according to the technical solution for the production of electrodes for galvanic cells, where it is important to avoid even small disturbances, in particular particles on the electrode, or to detect these disturbances in good time within the framework of the inspection of the electrode or its preform, if necessary before using the electrode to produce a finished galvanic cell. In addition, a problem that often exists in the production of such electrodes is that processes are used within the scope of the production of such electrodes, in which there is a possibility or risk of releasing small particles, in particular small carbon particles. This is especially the case when punching electrodes from larger substrates, when applying cathode or anode materials (for example carbon powder) in layers to an electrode substrate (for example copper foil), or when the applied layers are subsequently calendered. In particular, there may be situations in which very small particles, in particular black carbon particles, need to be detected within the scope of the inspection on the surface of an object of essentially the same color (for example a calendered carbon layer).

[0022] Various exemplary embodiments of the device will be described below. Unless explicitly excluded or technically infeasible, these embodiments can be arbitrarily combined with each other and with other aspects of the further description of the technical solution of the present invention.

[0023] In some embodiments, the transport device is configured to move the object relative to the image sensor device so that at least two mutually opposite sides of the object can be detected by the image sensor device simultaneously or sequentially using image sensor technology, in particular in the case of plate-shaped, cuboid or strip-shaped objects. In this case, the image sensor device can have one or more line scan cameras, in particular for each of the two sides to be detected. This makes it possible to inspect both sides with the same device.

[0024] In some embodiments, the transport device has: (i) a first transport device (which can in particular have a vacuum conveyor) which is configured to transport the object lying flat while a first side of the object is at least partially detected by the image sensor device; and (ii) a second transport device (which can in particular have a vacuum conveyor) which is configured to transport the object suspended while a second side of the object opposite the first side is at least partially detected by the image sensor device. For example, the transport device can be configured to first transport the object lying flat on the first transport device and check the first side, then transfer the object to the second transport device in a transfer area, for example by suction at the bottom side of the second transport device, and then check the second side, which is now freely accessible, from below. As a result, turning over the object can be omitted and a very efficient, time-saving inspection process can be achieved for both sides at the same time.

[0025] In other embodiments, the transport device comprises a turning device for turning over the object, which is configured to turn over the object between at least partially detecting a first side of the object using image sensing technology and at least partially detecting a second side of the object opposite the first side using image sensing technology. This makes it possible, in particular, to use the image sensing means on only one side of the transport device, despite the inspection of both sides. This allows the device to be particularly compact, in particular with a low overall height.

[0026] In other embodiments, the transport device comprises two conveying devices separated from each other by a gap (they can in particular each have a vacuum conveyor belt), each of which is configured to transport the object lying flat or suspended. The image sensor is configured to detect two mutually opposite sides of the object using image sensing technology, while the parts of the object detected on both sides by image sensing technology pass through the gap when the transport device is running. Therefore, these two sides can be inspected in particular simultaneously or in inspection periods that partially overlap in time, which is particularly advantageous for high process efficiency or achievable high throughput.

[0027] In some embodiments, the device also has a separation device connected to the image sensor mechanism upstream of the transport path for separating the object from the initial object, in particular the initial substrate (such as an arc, plate or strip). Thus, the inspection can be carried out on the basis of the already separated object, which is particularly advantageous for turning the objects in the process sequence or as a preparatory step to individually screen out objects identified as defective during the inspection. In particular, in those embodiments including separation, the transport device can also be configured to pause the transport before the next separated object is fed again to the image sensor mechanism for inspection.

[0028] In some embodiments, the transport device has: a transport platform connected to the separation device upstream of the transport path; and at least two asynchronously working fixing devices, each movable along the direction of the transport path, for temporarily fixing the object on the transport platform. The device is configured to coordinately control the movement of the fixing devices so that the fixing devices act in coordination to supply the initial object to the separation device step by step, so that the initial object is stationary relative to the transport device, and each step realizes a separation of the object from the initial object.

[0029] In some embodiments, the device also has at least one line scan camera connected to the image sensor device upstream of the transport path, in particular a cleaning device for cleaning the object arranged between the separation device and the image sensor device with respect to the transport path. In this way, not only can undesirable disturbances of the surface of the object to be inspected be detected, but the occurrence of such disturbances can also be reduced in advance, in particular if the disturbance is caused by particles loosely located on the surface.

[0030] In some embodiments, the image sensor device is configured such that at least one of its line scan cameras has an optical axis, the direction of which defines an acute angle φ <90° that can be fixedly or variably adjusted, in particular time-variably adjusted, relative to a support surface on the transport device for accommodating the object during the image sensing detection. Due to the acute angle φ, in particular, potential interferences with the image quality detection by scattered light reflected on the object at orthogonal incidence, in particular from radiation sources outside the lighting device, can be substantially avoided. In general, it can be expressed as follows: the optical axis(es) of the line scan camera(s) are oriented so that they do not extend coaxially with the irradiation direction defined by the illumination direction and / or the main direction of incidence of the beam of another irradiation source. In addition, the shadows cast by the object that may appear due to the acute angle φ are easier to detect and use for subsequent image analysis, so that interferences indicated by the shadow projection on the surface of the object to be inspected can be more easily identified. In addition, in the case of a variable adjustment of the angle φ, the field of view of the at least one line scan camera can also be changed, in particular dynamically changed, in particular according to the transport speed of the transport device for transporting the object to be inspected. Thus, surface parts of the object can be detected from different viewing directions within the framework of its examination using image sensing technology, which in particular allows the detection and evaluation of changes that may occur in the detected image material due to a changing angle φ, in particular for disturbances that can only be detected based on these changes.

[0031] In some embodiments, the image sensor device has at least one reflector and is configured such that at least one line scan camera has an optical axis pointing toward the reflector, so that the line scan camera can detect the image of at least one part of the object generated by the reflector by image sensing technology. This allows in particular a particularly compact, in particular flat, design, since the extension of the image sensor device in a direction orthogonal to the transport direction can be particularly small.

[0032] In some embodiments, in addition to the line scan camera, the image sensor device also has at least one further camera, whose field of view extends beyond the cumulative field of view of the line scan camera in a direction transversely, in particular orthogonally to the transport direction. As a result, it is particularly possible to inspect such regions of the object that extend beyond the cumulative field of view of the line scan camera, in particular projections. In particular, in the case of electrodes, in particular for lithium-ion batteries, such electrodes usually have a so-called discharge lug (Ableiterfahne) for conducting current from the electrode, which extends transversely beyond the electrochemically active surface of the electrode as a projection. If such an electrode is now transported by a transport device so that the discharge lug extends from the active surface of the electrode in a direction extending transversely, in particular orthogonally to the transport direction, the discharge lug can be inspected by the further camera even if it extends completely or partially beyond the cumulative field of view of the line scan camera. In particular, it is possible to inspect any transition between the electrode coating and the discharge lug. In many cases, the discharge lug is completely uncoated (i.e., not coated with the active material of the electrode), and there is a coating edge in the transition between the discharge lug and the electrode. In particular, not only particles but also coating defects and flaking of the coating, for example, can be detected as disturbances.

[0033] In some embodiments, the image resolution of the at least one line scan camera is at least 6.8 μm per pixel, preferably at least 2.0 μm per pixel. Thus, even very small disturbances, in particular particles of a considerable size (e.g., disturbances imaged on at least one pixel), can still be detected and detected by image sensing technology. Such sizes have proven to be particularly advantageous, at least with regard to the identification of carbon particles and other particles, in the context of electrode inspection during or after its production, in order to be able to identify disturbances that endanger the quality and / or safety of the electrode well, if necessary.

[0034] In some embodiments, the image sensor device has an optical device in its optical path, which has a magnification factor in the range of -0.675x to -0.875x, in particular a lens optical device with at least one optical lens. It has been shown that this magnification value is particularly advantageous for achieving a large field of view (FoV) in a compact structural form of the device. In particular, the optical device can here have at least one spacer ring for determining the magnification factor. This means that the magnification factor can remain particularly stable at the distance between the image sensor (in particular a line scan camera) and the optical device, which is (jointly) determined by one or more of the spacer rings. The distance between the optical device and the object is thus also clearly defined, at least in the sense of a minimum distance. Therefore, the desired field of view and the desired resolution can be achieved by using specific spacer rings, in particular in order to adjust the relationship between the defined distance of the optical device to the object and the distance of the optical device to the image sensor. In this case, the diameter of the spacing ring is preferably selected to be large enough to be able to keep the intensity of the radiation to be detected (in particular the light) incident on the sensor at least approximately uniform.

[0035] In some embodiments, the shielding device has one or more darkrooms, in which a total of N line scan cameras are placed to protect them from radiation that does not originate from the illumination device. Thus, it is possible to effectively prevent possible damage to the image quality provided by the image sensor mechanism and, therefore, to prevent possible damage to the quality of the inspection based thereon.

[0036] In some embodiments, the device is configured to control or regulate the recording frame rate of the image sensor device as a function of the transport speed of the object during continuous transport of the object by the transport device. Thus, according to a defined dependency (which can be defined in particular by a mathematical function), in particular (i) a change in the extension of the field of view of the image sensor device in the transport direction is regulated as a function of the transport speed, or (ii) the extension can also remain constant for different transport speeds. For this purpose, a measuring device (e.g. an encoder) can be provided in particular, which can be connected to the image sensor device and the drive of the transport device.

[0037] In some embodiments, the lighting device has one or more light-emitting diodes as radiation sources for illuminating each surface of the object to be inspected. This allows a very compact design with low energy consumption and / or at least essentially monochromatic illumination (and therefore particularly high image resolution).

[0038] In some embodiments, the lighting device has a main radiation direction and is configured to illuminate the surface of the object to be inspected, so that the main radiation direction extends during the image sensing technology detection at a fixed or time-varying acute angle α relative to the support surface for accommodating the object on the transport device, α<90°. Due to the acute angle α, any shadow projection caused by the object is caused and used for the subsequent image evaluation, so that disturbances on the surface of the inspected object indicated by the shadow projection can be more easily identified.

[0039] In some embodiments, the lighting device is configured to provide diffuse illumination of each object surface to be inspected. This makes it particularly easy to make visible interference that is not recognizable or difficult to recognize when directional lighting is only used from one illumination direction. In particular, when using diffuse illumination, shadow projections of particles or many other types of interference can be formed in different directions, and differences in the direction-dependent reflection of the incident beam on the object can also be recognized. Overall, this increases the probability of detecting interferences, especially very small interferences.

[0040] In some embodiments, the transport device is configurably configured so that its position is adjustable in a direction extending transversely, in particular orthogonally, to the transport path. This allows the transport path to be adjustable relative to the image sensor device, which can be used in particular to optimally bring the object to be examined into the field of view of the image sensor device.

[0041] In some embodiments, the device further comprises an image analysis device for analyzing image material acquired by the image sensor mechanism so as to identify possible deviations of an object imaged in the image material from a reference state of the object, in particular a predefined target state, by image processing.

[0042] A second aspect of the invention relates to a method for the sensor-based inspection of a physical object, in particular a plate-shaped or strip-shaped object, wherein the method is performed using a device according to any of the above-mentioned embodiments. The object can in particular be an electrode of a galvanic cell, in particular a lithium-ion battery cell or a lithium-ion battery, or a precursor of such an electrode, for example an electrode substrate (for example a copper foil) which has not yet been coated with an anode or cathode material or an electrode substrate which has been coated before or after calendering (rolling of the anode or cathode material) and / or separation.

[0043] A third aspect of the invention relates to the use of the device according to the first aspect or the method according to the second aspect, respectively, for checking an electrode substrate, in particular a plate-shaped or strip-shaped electrode substrate, or a coating of such an electrode substrate with an anodic or cathodic material, of an electrode of a galvanic cell. Such use can be carried out in particular within the framework of a process for manufacturing such an electrode, in particular enabling disturbances on the electrode surface, such as undesired particle deposits, to be detected early and defective products or prefabricated parts to be rejected as scrap or to be removed from the process for reprocessing before their manufacture is completed.

[0044] The features and advantages described in connection with the first aspect of the present invention are also applicable to the other aspects of the present invention accordingly. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Other advantages, features and applications of the present invention are described in detail below with reference to the accompanying drawings.

[0046] Figure 1 A first embodiment of a device for sensor-based inspection of one or more physical objects, in particular electrodes, is shown;

[0047] Figure 2 A second embodiment of the device is shown;

[0048] Figure 3 A third embodiment of the device is shown;

[0049] Figure 4 A fourth embodiment of the device is shown;

[0050] Figure 5 A first variation for arranging the image sensing mechanism is shown;

[0051] Figure 6 A second variation for arranging the image sensing mechanism is shown;

[0052] Figure 7 A third variation for arranging the image sensing mechanism is shown;

[0053] Figure 8 A fourth variation for arranging the image sensing mechanism is shown;

[0054] Fig. 9 A side view showing an arrangement of multiple line scan cameras of an image sensing mechanism;

[0055] Fig.10 A top view of a plurality of electrodes to be inspected located on a transport device and the position of the field of view of the camera of the image sensing mechanism relative to them is shown; and

[0056] Fig.11 It is shown that by means of the device, in particular Figure 1A flow chart of one embodiment of a method for inspecting an object in a device. DETAILED DESCRIPTION

[0057] In the accompanying drawings, the same reference numerals represent the same, similar or corresponding elements. The elements shown in the accompanying drawings are not necessarily drawn to scale. On the contrary, the various elements shown in the accompanying drawings are reproduced in a manner that those skilled in the art can understand their functions and general purposes. Unless otherwise clearly stated, the connection and coupling between the functional units and elements shown in the drawings can also be implemented as indirect connections or couplings. The functional units can be implemented in particular as hardware, software, or a combination of hardware and software.

[0058] exist Figure 1 A first embodiment 100 of a device for inspecting one or more physical objects O based on sensors is shown in FIG. In principle, various objects O having mutually opposing, substantially flat surfaces can be inspected. The object O can be in particular in the form of a strip, film, sheet or plate. The object O will be discussed below by way of example, wherein the object O is a film-shaped or plate-shaped electrode E of a primary cell, in particular a lithium-ion cell, but is not limited thereto.

[0059] The device 100 has a transport device, which includes a first vacuum conveyor belt 105a and a second vacuum conveyor belt 105b, which are each configured to transport an object O along a transport path at a speed v along a transport direction x, which speed v can be constant or change over time. Here, the two vacuum conveyor belts 105a and 105b are arranged relative to each other so that the object O can first be transported flat on the first vacuum conveyor belt 105a and then be further transported suspended by the second vacuum conveyor belt 105b (and vice versa, not shown). For this purpose, the two vacuum conveyor belts overlap in a transfer area and are spaced apart from each other there, so that the object O can be moved into the gap thus formed in the transfer area and can be sucked up there by the second vacuum conveyor belt so that the object can be further transported suspended on the second vacuum conveyor belt.

[0060] Thus, in the region of the first vacuum conveyor 105a, the first (upper) main surface of the respective object O is accessible while the object is placed on the first vacuum conveyor 105a with its second main surface lying opposite the first main surface. In the region of the second vacuum conveyor 105b, the object is placed suspended on the second vacuum conveyor 105b with its first main surface, while its second (lower) main surface is accessible.

[0061] In order to enable image sensing of the two main surfaces, the device 100 has an image sensing arrangement with two independent image capture units 110 a and 110 b, each of which has N digital line scan cameras 160, where N ≥ 1, in particular a group of a plurality of line scan cameras 160 arranged coaxially (in the Z direction) and therefore transversely, in particular orthogonally, to the transport direction x and adjacent to each other (see Fig. 9 and Fig.10 ). It will be exemplarily assumed below that each image sensing unit 110a or 110b has a plurality of line scan cameras 160, that is, N>1.

[0062] These line scan cameras 160 are configured to be able to scan the objects O transported along the image detection units 110a or 110b during their transport using image sensing technology in order to generate corresponding image material (image data), which at least partially represents the scanned surface and can serve as a basis for subsequent image analysis by the image analysis device 150 to identify disturbances at or on the corresponding surface, in particular possible particles. The image analysis device 150 can in particular be configured at the same time as a control device for the device 100, in particular for controlling its individual functional components and their interactions.

[0063] Each image sensing unit 110a and 110b is equipped with a shielding device 115a or 115b in the form of a darkroom, which is configured to provide extensive shielding for the field of view of the line scan camera 160 to prevent radiation, in particular scattered light, from outside the respective shielding device 115a or 115b. In order to illuminate the surface of the object O to be scanned by the line scan camera 160, an illumination device 120a or 120b is provided in each darkroom, which illumination device can in particular have one or more light-emitting diodes as radiation sources. Figures 5 to 10 More details of the lighting devices of the image sensing units 110a and 110b are described.

[0064] Each of the two image capture units 110a and 110b is connected upstream (with respect to the transport direction x) to a respective cleaning device 125a or 125b. Each cleaning device 125a or 125b is configured to clean, in particular to rinse contactlessly, the surface of the object O to be scanned by the subsequent image capture unit 110a or 110b. In this way, in particular deposited particles can be removed and the yield of defect-free objects can be increased as a result of the inspection results subsequently generated.

[0065] After the inspection part of the device 100 has been explained, the preparation part of the device 100 will be discussed next, which is connected upstream of the inspection part and is used to supply and separate the objects O to be inspected. In the preparation part, the device 100 has a supply roll (Vorratsrolle) 140 for providing a strip-shaped or film-shaped initial substrate B, in particular an electrode substrate (for example, a metal film, which may have been coated with an anode or cathode material). In addition, the device 100 also has a separation device 130 in the preparation part, which can be designed in particular as a punching machine, such as a roller punching machine, for separating individual objects O, in particular electrodes E (optionally with discharge lugs A) from the initial substrate B, in particular cutting or punching.

[0066] In particular, the separation device 130 may include a lower tool and an upper tool. The upper tool may include an eccentric drive shaft for cyclically moving the cutting blade or punch toward the initial substrate B. The separation device 130 may also have a clamping device that enables clamping of the individual objects O to be cut or punched from the initial substrate B before and / or during the cutting process or punching process. This enables particularly positionally accurate cutting or punching of the objects O. The clamping device may be mechanically connected to the upper tool.

[0067] The supply of the initial substrate B from the supply roll 140 to the separation device 130 is realized in particular by a plurality of guide rollers 135, one or more of which, in particular a pair of rollers, can be driven. In addition, a transport table 145 can be arranged in the preparation section, which has two associated fixtures 145a and 145b, which are mounted on the transport table 145 so as to be translationally movable at least along the transport direction x. The transport table 145 and its fixtures 145a and 145b are configured to supply the initial substrate B to the separation device 130 in a stepwise manner.

[0068] In particular, the configuration can be designed such that during the operation of the transport platform 145, the initial substrate B is first grasped by the fixture 145a and pulled or pushed in the direction of the separation device 130, while the fixture 145b is released, that is, the initial substrate B is not fixed. The feeding (Vorschub) is designed to bring the initial substrate B to a preset cutting or punching position relative to the separation device 130, so that when the fixture 145b fixes the initial substrate B in the next step and the fixture 145a returns to its initial position, the initial substrate B can be separated into individual objects O or electrodes by the separation device 130, and the initial substrate is held in place by the fixture 145b. Therefore, the continuous transportation of the transport device here only involves the objects O that have been separated. On the other hand, the initial substrate B is transported in a step-by-step manner as described above, with pauses between steps, during which separation occurs. Alternatively, the initial substrate B can be fixed on the support (Auflage) of the transport platform 145 under negative pressure. In some embodiments, the transport table 145 can be connected upstream (with respect to the transport direction x) to a storage section, ie a belt buffer (not shown), for at least temporary intermediate storage of the initial substrates B. This allows the initial substrates B to be fed continuously upstream of the transport table 145 .

[0069] Figure 2 A second embodiment 200 of the device is shown, which is a variant of embodiment 100. This is obtained by pivoting the second vacuum conveyor belt 105b about the z direction by a fixed angle relative to the first vacuum conveyor belt 105a. The units assigned to the second vacuum conveyor belt 105b, in particular the cleaning device 120b, the shielding device or the darkroom 115b and the image detection unit 110b and the lighting device 120b located therein are also pivoted accordingly. In this way, the device can especially realize a particularly compact structural form. The device 200 can especially have a preparation part corresponding to the device 100 (in Figure 2 Only part of it is shown).

[0070] Figure 3 A third embodiment 300 of the device is shown, which is also a variant of embodiment 100. The difference is that the two vacuum conveyors 105a and 105b are arranged here so that there is a gap between them along the transport direction x, through which the object O can pass and be detected by image sensing technology on both sides by the image detection units 110a and 110b, which are arranged opposite each other here. Another difference is that the object O is placed on the two vacuum conveyors 105a and 105b on the same side, in particular lying flat as shown in the figure. A variant of this embodiment is also conceivable, in which the object is transported suspended.

[0071] In particular, the device 300 may also have a preparation part (in Figure 3), which corresponds to the preparation part of device 100. Embodiment 300 in particular allows simultaneous image sensing detection of object O on both sides and, due to the relative arrangement of the two image capture units 110a and 110b, also allows a particularly compact design.

[0072] Figure 4 A fourth embodiment 400 of the device is shown, which is likewise a variant of embodiment 100. The difference is that only one vacuum conveyor belt 105 and one image sensing unit 110 as well as the associated shielding device 115 and lighting device 120 are provided here. In order to be able to detect the object using image sensing technology on both sides here as well, the device 400 has a flipping device 155, which is configured to flip the object O placed on the vacuum conveyor belt 105 with a first side so that it is placed on the same vacuum conveyor belt 105 with a second side opposite to the first side. In this way, the same image sensing unit 110 can be used to detect the first side using image sensing technology before flipping and to detect the second side using image sensing technology after flipping. There are many possible embodiments of the flipping device 155, in particular in addition to Figure 4 In addition to the configuration shown, it is also conceivable that the objects are fed to the image capture unit 110 again from the front after being turned over, ie from the end of the vacuum conveyor belt 105 facing the separating device 130 .

[0073] The device 400 may also have a preparation part corresponding to the device 100 (in Figure 4 Embodiment 400 in particular allows simultaneous image sensing of both sides of object O by one image capture unit 110 and thus enables a particularly compact design.

[0074] Figure 5A first variant 500 of the arrangement of an image sensor device or its components assigned to the corresponding image acquisition unit 110 (or 110a, b) is shown. The shielding device 115 is not shown here. The image acquisition unit 110 has at least one line scan camera 160, in particular (as mentioned above) a group of multiple coaxially arranged line scan cameras 160. Each line scan camera 160 is combined with an optical device 180, which has at least one first lens 170, which is separated from the line scan camera 160 by a first spacing ring 165. This spacing is particularly important for (together) determining the magnification factor of the optical device 180. The magnification factor can be in particular in the range of -0.675x to -0.875x. In addition, the optical device 180 can also have a second spacing ring 175, in which a second lens (or multiple lenses) can also be arranged. Overall, the optical device 180 therefore defines an optical imaging of a surface portion of the object O currently located in the field of view along the optical axis 185 of the image capture unit 110 onto the line scan camera 160 corresponding to the optical device 180 .

[0075] The lighting device 120 here has at least one light source, in particular two light sources as shown in the figure, which illuminate the surface portion of the object to be detected by the image sensing technology from above at a corresponding angle α from different sides, which angle can be an acute angle (α<90°). In the case of multiple light sources, the individual angles α can be different depending on the light source, or they can be the same as shown in the figure, in order to achieve the most uniform illumination possible. The use of such oblique incidence is particularly advantageous for avoiding reflections of the radiation of the lighting device 120 on the surface of the object O along the optical axis 185. Due to the acute angle α, shadow projections caused by the object O can also occur and be used for subsequent image analysis, so that disturbances indicated by shadow projections on the surface of the inspected object can be more easily identified.

[0076] The image capture unit 110 is translationally movable along the y direction and / or the z direction. As a result, on the one hand, the size of the field of view can be adjusted, and on the other hand, its relative position relative to the vacuum conveyor 105 or the object O transported thereby can be adjusted along the z direction extending orthogonally to the transport direction x. Adjustability along the x direction is also conceivable, which can be used in particular to adapt the position of the image capture unit 110 to different product sizes. The image capture unit 110a or 110b or the shielding device 115a or 115b can in particular be arranged on rails that are translationally movable along the z direction and can be removed from the shielding device 115, for example, for maintenance.

[0077] Figure 6A second variant 600 of the arrangement of image sensors or components thereof associated with the respective image acquisition unit 110 (or 110a, b) is shown. Variant 600 is a variation of first variant 500, in which the image acquisition unit 110 is tilted with respect to the transport direction x or the perpendicular to the surface of the vacuum conveyor belt 105 (or 105a, b) and thus encloses an (acute) angle φ, φ<90°.

[0078] Figure 7 A third variant 700 of the arrangement of the image sensor arrangement is shown, which is particularly applicable to Figure 3 A particularity of the third variant 700 is that the two image detection units 110a and 110b are arranged so that their respective optical axes extend parallel to the transport direction x and point to the respective reflectors 190a and 190b, respectively, which deflect the surface portion of the respective side of the object O to be scanned in the direction of the respective optical axis, respectively, so as to allow image sensing technology detection by the corresponding line scan camera 160. Therefore, in particular, a particularly flat (with respect to the y direction) structural form can be achieved.

[0079] Figure 8 A fourth variant 800 of the arrangement of the image sensing mechanism is shown, which is a variant of the variant 700 and can be applied to Figure 3 Compared with variant 700, variant 800 has a plurality of Figure 8 The upper and lower parts of the apparatus 160 each have at least one further image detection unit 110c or 110d, which are arranged such that their respective optical axes extend parallel to the transport direction x and point to the respective reflectors 190a or 190b, which deflect the surface portion of the respective side of the object O currently to be scanned in the direction of the respective optical axis, in order to allow image sensing detection by the respective line scan camera 160. Thus, in particular, the device can be of flat construction (with respect to the y direction).

[0080] Fig. 9A detailed view 900 of the image capture unit 110 in a side view opposite to the transport direction (x direction) is shown. The image capture unit 110 has a plurality of line scan cameras 160, each of which has at least one row of K camera pixels, where K>1, which as a whole cooperate with the optical device 180 (not shown here) to (jointly) define the field of view 195a to 195f of the respective line scan camera 160. The value of K can be different for different line scan cameras 160. Here, the line scan cameras 160 are coaxially arranged along the z direction so that their respective fields of view 195a to 195f overlap with the adjacent fields of view, so that an uninterrupted scanning area oriented along the z direction is obtained as a whole. In addition, a further camera 111 with its own field of view 196 can be provided, which can also be a line scan camera or a 2D or 3D camera. In the present example, it is particularly used to extend the cumulative field of view of the image sensing unit 110 laterally in the z-direction in order to be able to detect lateral protrusions of the object O which extend outwards from the cumulative field of view of the line scan camera 160 .

[0081] This is Fig.10 , which shows an application example 1000 in a top view of an object located on a vacuum conveyor belt 105, wherein electrodes E of a galvanic cell are used as the object O to be inspected, wherein each electrode E has a lateral projection A, which serves to conduct current from the electrode when the electrode is later used in a galvanic cell, and is generally referred to as a discharge lug. The further camera 111 is used to specifically inspect the discharge lugs, while the line scan camera 160 is used to inspect the main surface of the electrode E that is chemically active in subsequent operations. In particular, the dimensions of the discharge lugs and, for example, the coating transition between the active main surface and the discharge lug can also be inspected.

[0082] In one embodiment, the single-sided or double-sided inspection of the discharge lug using the camera 111 can be performed upstream of the separation device 130, that is, before or after the inspection using the image sensor mechanism 110 in terms of time. For example, the surface quality of the discharge lug can be determined by dark field illumination (approximately 45 degree illumination). During the inspection, one or more different illumination patterns can also be generated on the surface of the discharge lug and used to illuminate the surface. Since the discharge lug usually does not have a coating with active material, it usually has good light reflectivity, which may require additional lighting. Therefore, it is also conceivable to have a line scan camera 160 and another camera 111 with local Separate fields of view (FoV) from each other.

[0083] A possible advantage of inspecting the lugs upstream of separation is that the transport speed there can be lower.

[0084] Checking the discharge lugs can be performed in particular when the speed of the initial substrate B is lower than the speed of the individual objects O during their inspection by the image sensing mechanism 110 .

[0085] Fig.11 A flow chart showing an exemplary embodiment 1100 of a method for sensor-based inspection of a physical object, which method may be performed in particular using a device according to the technical solution of the present invention, for example according to an embodiment of the device described herein. Figure 1 The embodiment 100 is shown for illustration.

[0086] The method comprises a process 1105 of supplying an initial substrate B, in particular an electrode substrate, to a separation device 130 of the apparatus. In a next process 1110, the separation device 130 is used to separate individual electrodes E (or their precursors) from the initial substrate B, in particular by cutting or punching.

[0087] Next, in the next process 1115, the separated electrode E is received by a first transport device, in particular a first vacuum conveyor 105a, and is continuously transported during the subsequent operation of the method 1100. During the transport, the electrode is guided by the first transport device through a cleaning device 125a, where the first main surface of the electrode E is cleaned, in particular by suction and / or blowing (optionally using ionized blowing), before the electrode is detected by the first image detection unit 110a in the next process 1125 using image sensing technology.

[0088] Subsequently, the electrode E is transferred to a second transport device, in particular a second vacuum conveyor belt 105b, more precisely in such a way that the second main surface of the electrode E, which is opposite to the first main surface, becomes accessible for inspection. Figure 1 As explained, this can be achieved in particular by the electrode E being transported further suspended from now on on the second vacuum conveyor belt 105 b .

[0089] Next, the cleaning process 1140 is carried out again, this time for the second main surface, and then the second main surface is detected by the second image detection unit 110b using image sensing technology 1145. The digital image material, in particular the video material, detected by the two image detection units 110a and 110b is provided to the image analysis unit 150 of the device, in which the image material is analyzed. This analysis can be carried out in particular by comparing the image material with a reference image material, which can in particular correspond to an undisturbed surface of the electrode, so that if necessary, the deviation of the surface shown in the image material from the corresponding surface of the reference image material can be identified and analyzed, in particular classified, by an image comparison method, in particular an automatic image comparison method. It is also conceivable to use an analysis method based on machine learning for this purpose. This analysis provides a check result, which at least indicates whether a disturbance has been identified. In more complex classifications, it is also conceivable that the check result additionally or alternatively indicates the frequency and / or type of the identified disturbance.

[0090] Finally, the inspection results can be used in the next process 1155 to further process the inspected electrode based on the inspection results, for example combining it into a galvanic cell through at least one separator and another electrode with opposite polarity, or to remove it as a defect, thereby saving time and material for further processing, which are no longer valid at that time.

[0091] Although at least one exemplary embodiment has been described above, it should be noted that a large number of variations are possible. In this case, it should also be noted that the exemplary embodiments described are only non-limiting examples, which should not limit the scope of protection, applicability or configuration of the devices and methods described herein in any way. On the contrary, the foregoing description will provide those skilled in the art with instructions for implementing at least one exemplary embodiment, wherein it should be understood that various changes may be made to the functions and arrangements of the elements described in the exemplary embodiments without departing from the subject matter respectively identified in the attached claims and their legal equivalents.

[0092] Reference numerals list

[0093] 100 A first embodiment of a device for detecting one or more physical objects, in particular electrodes, based on a sensor

[0094] Implementation

[0095] 105, 105a, b Vacuum conveyor belt, corresponding components of the transport device

[0096] 110, 110a-d image detection unit

[0097] 111 Additional cameras, especially for checking discharge lugs A

[0098] 115, 115a, b Shielding device, especially darkroom

[0099] 120, 120a, b lighting device with light emitting diode

[0100] 125a, b cleaning device

[0101] 130 Separation device, especially punching device

[0102] 135 Guide roller for strip electrode substrate B

[0103] 140Supply roll for strip electrode substrate B

[0104] 145 transport platform

[0105] 145a, b Fixing device

[0106] 150 Image analysis device, optionally also controlling the device

[0107] 155 Flipping device

[0108] 160 Single Line Scan Camera

[0109] 165 First spacer ring

[0110] 170 First lens

[0111] 175 A second spacer ring having a second lens

[0112] 180 Optics

[0113] 185 linescan camera 160 optical axis

[0114] 190a, b reflector

[0115] 195a-f Field of view of each line scan camera 160

[0116] 196 Field of view of another camera 111

[0117] 200 Second Implementation of the Device

[0118] 300 Third embodiment of the device

[0119] 400 Fourth embodiment of the device

[0120] 500 First Variation of Arrangement of Image Sensing Mechanism

[0121] Second variation of the arrangement of the image sensing mechanism 600

[0122] Third variation of arrangement of image sensing mechanism 700

[0123] 800 Fourth variant of the arrangement of the image sensor mechanism 900 Detailed view of the image acquisition unit 110 900

[0124] Application example of 1000 electrode inspection

[0125] A Discharge Ear

[0126] B initial object, especially a flat initial substrate

[0127] E (separated) electrode

[0128] O Object to be inspected, in particular electrode with / without discharge lug A v Transport speed

[0129] x, y, z are the axes of a Cartesian coordinate system.

Claims

1. A device (100; 200; 300; 400) for inspecting a physical object (O) based on a sensor, wherein the device (100; 200; 300; 400) has: A transport device (105; 105a, 105b) for transporting a physical object (O) to be inspected along a transport path; An image sensing device (110; 110a, 110b) having at least one image sensor (160) for detecting the object (O) at least partially by image sensing technology during the continuous movement of the object along the transport path relative to the image sensing device (110; 110a, 110b) by the transport device (105; 105a, 105b); an illumination device (120; 120a, 120b) for illuminating respective surfaces to be inspected of the object (O) within a wavelength range detectable by the image sensing means (110; 110a, 110b), so that the image sensing means (110; 110a, 110b) can detect the surface at least partially in the area of ​​the surface thus illuminated using image sensing technology; and Shielding means (115; 115a, 115b) for shielding the image sensing mechanism (110; 110a, 110b) from radiation not originating from the illumination device (120; 120a, 120b); in, The image sensor system (110; 110a, 110b) has a number N of digital line scan cameras (160), wherein N≥1, each of which has a plurality of camera pixels arranged in a row, wherein the rows of the line scan cameras (160) each extend transversely to the transport path.

2. The device (100; 200; 300; 400) according to claim 1, wherein The transport device (105; 105a, 105b) is configured to move the object (O) relative to the image sensing mechanism (110; 110a, 110b) so that at least two mutually opposite sides of the object (O) can be detected simultaneously or sequentially by the image sensing mechanism (110; 110a, 110b) using image sensing technology.

3. The device (100; 200) according to claim 2, wherein: The transport device (105; 105a, 105b) comprises: A first transport device configured to transport the object (O) lying flat while a first side of the object (O) is at least partially detected by the image sensing mechanism (110; 110a, 110b); and A second transport device is configured to transport the object (O) in a suspended manner while a second side of the object (O) opposite to the first side is at least partially detected by the image sensor mechanism (110; 110a, 110b).

4. The device (400) according to claim 2, wherein: The transport device (105; 105a, 105b) has a flipping device (155) for flipping the object (O), and the flipping device is configured to flip the object (O) between a first side of the object (O) at least partially detected by image sensing technology and a second side of the object (O) opposite to the first side at least partially detected by image sensing technology.

5. The device (300) according to claim 2, wherein: The transport device (105; 105a, 105b) comprises two conveying devices separated from each other by a gap, the conveying devices being respectively configured to transport the object (O) in a flat or suspended state, and the image sensing mechanism (110; 110a, 110b) being configured to detect two mutually opposite sides of the object (O) using image sensing technology, and the parts of the object (O) detected on both sides using image sensing technology pass through the gap when the transport device (105; 105a, 105b) is running.

6. The device (100; 200; 300; 400) according to any one of the preceding claims also has a separation device (130) connected to the image sensing mechanism (110; 110a, 110b) upstream of the transport path, for separating the object (O) from the initial object (B).

7. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The transport device (105; 105a, 105b) comprises a transport platform (145) connected to the separation device (130) upstream of the transport path and at least two asynchronously working fixing devices (145a, 145b) movable along the direction of the transport path, respectively, for temporarily fixing the object (O) on the transport platform (145); Wherein, the device (100; 200; 300; 400) is configured to coordinately control the movement of the fixing devices (145a, 145b) so that the fixing devices act in cooperation to supply the initial object (B) step by step to the separation device (130), thereby achieving a separation of the object (O) from the initial object (B) in each step while the initial object (B) is stationary relative to the transport device (105; 105a, 105b).

8. The device (100; 200; 300; 400) according to any of the preceding claims also has a cleaning device (125a; 125b) of at least one line scan camera (160) connected to the image sensing mechanism (110; 110a, 110b) upstream of the transport path, for cleaning the object (O).

9. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The image sensing device (110; 110a, 110b) is configured so that at least one of its line scan cameras (160) has an optical axis (185), the direction of which defines an acute angle φ that can be fixedly or variably adjusted relative to a support surface on the transport device (105; 105a, 105b) for accommodating the object (O) during detection using image sensing technology, wherein φ<90°.

10. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein The image sensing mechanism (110; 110a, 110b) has at least one reflector (190a; 190b) and is configured so that at least one of the line scan cameras (160) has an optical axis (185) pointing toward the reflector (190a; 190b), thereby enabling the line scan camera (160) to detect a mirror image of at least a portion of the object (O) generated by the reflector (190a; 190b) using image sensing technology.

11. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: In addition to the N line scan cameras (160), the image sensing device (110; 110a, 110b) also has at least one other camera (111), the field of view (196) of which extends beyond the cumulative field of view (195a, ..., 195f) of the N line scan cameras (160) in a direction extending transversely to the transport direction (x).

12. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The image resolution of at least one of the line scan cameras (160) is at least 6.8 μm per pixel, preferably at least 2.0 μm per pixel.

13. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The image sensor device (110; 110a, 110b) has an optical device (180) in its optical path, the magnification factor of which is in the range of -0.675x to -0.875x.

14. The device (100; 200; 300; 400) according to claim 13, wherein The optical system (180) has at least one spacing ring (165; 175) for determining the magnification factor.

15. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein The shielding device (115; 115a, 115b) has one or more darkrooms, in which a total of N line scan cameras (160) are placed to protect the line scan cameras from radiation that does not originate from the lighting device (120; 120a, 120b).

16. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The device (100; 200; 300; 400) is configured to control or adjust the shooting frame rate of the image sensing mechanism (110; 110a, 110b) according to the transportation speed of the object (O) during the continuous transportation of the object by the transportation device (105; 105a, 105b).

17. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The lighting device (120; 120a, 120b) has one or more light-emitting diodes as radiation sources for illuminating each surface of the object (O) to be inspected.

18. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The lighting device (120; 120a, 120b) has a main radiation direction and is configured to illuminate the surface to be inspected of the object (O) so that the main radiation direction extends at a fixed or time-varying acute angle α relative to a supporting surface for accommodating the object on the transport device (105; 105a, 105b) during detection using image sensing technology, wherein α<90°.

19. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein: The illumination device (120; 120a, 120b) is configured to provide diffuse illumination for each corresponding surface of the object (O) to be inspected.

20. The device (100; 200; 300; 400) according to any one of the preceding claims, wherein The transport device (105; 105a, 105b) is configurably designed so that its position is adjustable along a direction extending transversely to the transport path.

21. The device (100; 200; 300; 400) according to any of the preceding claims also has an image analysis device (150) for analyzing the image material detected by the image sensing mechanism (110; 110a, 110b) so as to identify possible deviations of the object (O) imaged in the image material from a reference state of the object by image processing.

22. A method for sensor-based inspection of a physical object (O), wherein: The method is performed using a device (100; 200; 300; 400) according to any one of the preceding claims.

23. Use of the device (100; 200; 300; 400) according to any one of claims 1 to 21 or the method according to claim 22 for checking an electrode substrate of an electrode (E, A) of a galvanic cell or a coating of the electrode substrate with an anode or cathode material.

Images