Method for automatically regulating a machine for applying lubricants and device for automatically regulating a machine for applying lubricants

Abstract

The invention relates to a method for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate, in particular a metal plate (2). The machine (1) comprises at least one coating unit (3), at least one pump unit (5) connected to the at least one coating unit (3) via at least one conveyor line (4), at least one sensor unit (7) for performing a spatially resolved optical or spectroscopic measurement method, a control unit and a data processing unit (9). Furthermore, it relates to a device for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate. With the method according to the invention and the device according to the invention, the object of achieving a fully automated and continuous process flow is achieved, taking into account the process quality and, if necessary, adjusting the control parameters.

Description

Technical Field

[0001] The invention relates to a method for automatically regulating a machine for applying a lubricant to one or both sides of a substrate, in particular a metal sheet, and a device for regulating a machine for applying a lubricant.

[0002] In the sense of the present invention, the term "substrate" may include a large number of workpieces, machine parts or components on which or on whose surface the lubricant is applied. In particular, in the sense of the present invention, a "substrate" may refer to a flat article extending on a plane, such as a metal plate. Background Art

[0003] The metal sheet may be subjected to a series of mechanical loads or external influences (temperature fluctuations, humidity, etc.) during its handling, processing, storage or transportation. In order to increase the resistance of the metal sheet to this type of loads or influences, the metal sheet can be coated with a liquid anti-corrosion oil (pre-lubricant) or a lubricating oil or a dry lubricant (hot melt adhesive). Dry lubricants can also have anti-corrosion properties. The difference between pre-lubricants and hot melt adhesives is that pre-lubricants are liquid at room temperature, while hot melt adhesives are solid or paste-like at room temperature. In addition to certain special properties (for example, anti-corrosion), the lubricant also has other properties and contains additives formulated with it. If one of the above-mentioned substances does not have a lubricating function, it is still covered by the present invention. Within the scope of the disclosure herein, the term "lubricant" is not limited to the above-mentioned substances. For example, it can also include oils suitable for use in the food industry or agriculture. For example, vegetable oils and fatty acid esters.

[0004] Anticorrosion oils are used in particular to protect metal sheets (e.g. sheet metal) from corrosion during storage or transportation. This type of oil can also protect the metal sheets from mechanical damage (e.g. scratches) or friction oxidation. In addition, such oils can support the forming of the metal sheets in a punching machine.

[0005] Often, metal sheets are subjected to forming or stamping processes during their production. Here, prior to processing, the metal sheets, which may also be in the form of metal strips, are coated with a lubricant. The applied lubricant reduces the friction that occurs during the forming or stamping process. It should also be noted that tensile loads that can lead to fractures of the metal sheet may occur during processing, for example. In order to reduce this risk, the metal sheet can be coated with a lubricant.

[0006] The lubricant coating and / or oiling of the metal sheet is carried out by so-called oilers. In particular, contact oilers and non-contact oilers are known. The contact oiler applies the lubricant or oil to the metal sheet by means of a roller (e.g., a brush roller or a felt roller), whereas in non-contact lubricant coating, the lubricant is applied by spraying onto the metal sheet.

[0007] To this end, the oiler comprises a coating unit which generates a spray under the action of compressed air or an electric field. Here, the lubricant passes through the discharge opening of the coating unit in the direction of the substrate. Here, the spray coating can be carried out in a spray chamber belonging to the oiler, into which the metal sheet is introduced and led out after oiling. The discharge opening can be arranged above and below the metal sheet. An electric field can be placed downstream of the discharge opening to form a uniform oil layer. Then, during spraying, there are lubricant droplets that form a spray under the action of the electric field. In addition to the oiler provided with a spray chamber as described, a spray bar system is also known. The spray bar system is used in particular in electrostatic oiling. Systems for performing point oiling are also known, that is, locally applying the lubricant to the substrate. Here, oiling can be carried out by passing the lubricant through one or more discharge openings. In this variant, it is also conceivable to distribute the lubricant by the action of compressed air or by applying an electric field.

[0008] When applying lubricants, it is crucial to check the quality of the lubricant applied on the substrate or metal sheet. It is crucial for a sufficient lubricant application that the lubricant is evenly distributed on the metal sheet without dry areas. Therefore, complete lubricant coating and avoidance of uncoated (dry) areas are desired. In addition, it is important to determine possible mixtures with external lubricants. The oil coating, for example, is a parameter from which information about a uniform lubricant distribution can be derived, which is preferably expressed in g / m 2 In addition, the layer thickness of the oil film as well as the layer thickness distribution also play a decisive role. This is because an inhomogeneous layer thickness distribution can indicate undesired lubricant indentations on the metal sheet. The parameters can be varied according to customer requirements.

[0009] Different investigation methods are known for detecting the oil coating, layer thickness or layer thickness distribution, lubricant purity and the homogeneity of the lubricant applied to the metal sheet. In addition to visual inspection by the human eye, spectroscopic and optical, in particular camera-based analysis methods are particularly suitable for this. As spectroscopic methods, fluorescence spectroscopy and infrared spectroscopy are particularly relevant. When inspecting metal sheets with lubricant droplets applied, fluorescence spectroscopy measurements show advantages over infrared spectroscopy. For inspection by fluorescence spectroscopy, the oil film does not need to be pre-homogenized. Determining the oil coating thickness by fluorescence spectroscopy has been well known for a long time, for example in EP 1 287 310 B1 and DE 10 2015 007 054 A1. The latter disclosure also describes the possibility of determining the layer thickness using measurements based on infrared spectroscopy.

[0010] DE 195 07 119 A1 discloses a laser-induced fluorescence spectroscopy method, by means of which contaminants in fluid systems can be detected. Laser-induced fluorescence spectroscopy is already used in industry to examine metal surfaces to which lubricants have been applied.

[0011] DE 10 2008 050 598 A1 discloses a method for detecting faulty oil loading of steel strips (so-called steel coils). The detection is based on the principle of UV fluorescence. After irradiation of the oiled steel strip, the reflected part of the UV light is focused, preferably by means of a convex lens. Its spectrum is recorded by an additional sensor. An evaluation device calculates possible process errors based on the sensor data, in particular by means of the spectral ratio of the emitted and reflected UV light. Process errors are oil-free (i.e. dry and uncovered) areas and the ingress of external lubricants. Although oil coverage errors can be detected using the method described above, a disadvantage is that, for example due to incorrect oil loading, automatic control of process parameters together with regulation cannot be achieved using the method. The method described is not very suitable for continuous process management or fully automatic process control.

[0012] In the method known from DE 198 47 258 A1, the oil layer applied to the metal sheet is not sensed directly, but the spray sprayed out of the nozzle of the oiler is sensed (a CCD camera detects the reflection trajectory of the laser beam passing through the spray). However, a good / bad decision is made on the basis of the measurement results regarding the coating process. Depending on this, control variables such as temperature, voltage or volume flow can be changed or readjusted. The disadvantage here is that the directly existing oil coating of the metal sheet cannot be determined, but the spray spray is checked indirectly (i.e., measured indirectly). Inhomogeneities due to material unevenness of the metal sheet cannot be detected or are only detected inadequately with this method.

[0013] WO 00 / 22421 A1 discloses a fluorescence-based method for determining the type of oil or the oil load on a surface before cleaning the surface. The measuring steps performed here are automated. In addition, in response to the measurement results, a warning signal can be automatically generated or a parameter check can be initiated (e.g., checking the composition of the cleaning agent solution before the actual measurement process). However, fully automatic control of the checking system is not disclosed.

[0014] The method for lubricant coating or the method for checking and controlling lubricant coating can also be used for other workpieces such as metal sheets. Therefore, DE 600 26 599 T2 discloses a lubricant control system for a system for machine parts. The system here also includes a lubricant film thickness measuring device and a control device. The measuring device can be based on a fluorescence measurement method. The supply amount of lubricant can be adjusted according to the measurement results.

[0015] None of the above-mentioned disclosures relates to a fully automatic control of an oiling machine which takes into account the local lubricant situation on the metal sheet coated with lubricant on the one hand and the operating parameters of the machine on the other hand. Summary of the invention

[0016] The object of the present invention is therefore to provide a method for controlling a machine for applying a lubricant to metal sheets which allows a fully automated and continuous process sequence while taking into account the process quality and, if necessary, the adjustment of control and regulation parameters.

[0017] As described above, the present invention relates to a method for automatically regulating a machine for applying a lubricant to one or both sides of a substrate, in particular a metal sheet. The machine comprises at least one coating unit, at least one pump unit connected to the at least one coating unit via at least one conveying line, at least one sensing unit for performing a spatially resolved optical or spectroscopic measurement method, a regulation unit and a data processing unit. The method according to the invention comprises the following steps:

[0018] a. using at least one pump unit: delivering lubricant via at least one delivery line in the direction of at least one coating unit;

[0019] b. measuring at least one first analysis parameter using at least one measuring unit assigned to the at least one pump unit, or determining the at least one first analysis parameter according to a machine parameter;

[0020] c. using the at least one coating unit: applying a lubricant to at least one side of the substrate or metal plate;

[0021] d. measuring at least one second analysis parameter using a sensing unit;

[0022] e. using a data processing unit: calculating at least one first quality parameter based on the at least one first analysis parameter and the at least one second analysis parameter;

[0023] f. using a data processing unit: comparing the at least one quality parameter with at least one first default parameter, wherein, as a result of the comparison, a positive or negative determination is made;

[0024] g. In case of a negative decision: automatically checking and / or changing at least one setting parameter by the control unit; and in case of a positive decision: executing a control loop and / or releasing the substrate or metal plate.

[0025] The invention also relates to a device for automatically regulating a machine for applying a lubricant to one or both sides of a substrate, in particular a metal plate. The machine comprises:

[0026] a. at least one coating unit for coating the lubricant on at least one side of the substrate or metal plate,

[0027] b. at least one pump unit, which is connected to the at least one coating unit via at least one conveying line and is used to convey lubricant in the direction of the at least one coating unit via at least one conveying line,

[0028] c. at least one measuring unit assigned to the pump unit for measuring at least one first analysis parameter, or a unit for determining the at least one first analysis parameter from a machine parameter,

[0029] d. at least one sensing unit for performing a spatially resolved optical or spectroscopic measurement method and for measuring at least one second analysis parameter,

[0030] e. A data processing unit, which is constructed as

[0031] i. calculating at least one first quality parameter based on the at least one first analysis parameter and the at least one second analysis parameter,

[0032] ii. comparing the at least one quality parameter with at least one first default parameter, and

[0033] iii. make an affirmative or negative determination as a result of the comparison, and

[0034] f. A control unit, which is constructed as

[0035] i. in the case of a negative decision, automatically checking and / or changing at least one setting parameter by the data processing unit, and

[0036] ii. In case of a positive determination, the control loop is traversed and / or the substrate or metal sheet is released for further processing.

[0037] With the method or the device for automatically controlling a lubricant application machine, on which the invention is based, the current and local lubricant situation on the metal sheet is taken into account directly after the lubricant has been applied to the substrate or the metal. In particular, flat products extending in a plane are suitable as substrates in the sense of the invention. In practice, for example when producing metal sheets for new customers, it often happens that the type of lubricant in the oiling machine is changed. Residues of previously used lubricants can lead to the undesired application of lubricants that are mixed with one another. The method according to the invention and the device according to the invention make it possible to detect the presence of mixed lubricants on the substrate and to control the machine in accordance with the result of the detection.

[0038] With the method on which the invention is based, it is possible to determine an indication of the presence of a mixed lubricant on a substrate or metal sheet. For example, with the method or device described herein, it is possible to detect whether the amount of the lubricant mixture is above or below a still acceptable limit value. In addition, the lubricant mixture can be detected spatially. For example, it can be determined whether the mixed lubricant has been applied to the metal strip within the first few meters. As a result of these determinations, a process determination is performed in a closed control circuit, which process determination can be accompanied by, for example, a check or change of operating parameters and measurement parameters. It can also be automatically determined whether the lubricant application is continued, paused or terminated. As a result of this determination, the metal sheet can be released for further transport or further processing. Alternatively, it can also be declared as waste or reprocessed. The same applies to the detection of a dry (i.e., unlubricated) position of a substrate or metal sheet. With the method according to the invention or using the device according to the invention, this "dry" position can also be detected, for example, also with spatial resolution. As a result of this determination, a process determination can be performed in a closed control circuit, which process determination can be accompanied by an automatic check or change of operating parameters and measurement parameters.

[0039] The lubricant condition on the substrate or metal plate, in particular the lubricant mixture or the dry position detection, is detected by one or more sensing units. A spatially resolved optical or spectroscopic measurement process is performed using the sensing units. In this case, spatial resolution can be performed by moving the sensing unit relative to the substrate surface, wherein measurements are performed at a large number of positions. In addition, similar to imaging measurement methods including fixed sensors, spatially resolved measurements can be performed by arranging one or more sensing units in a fixed position and the measuring method itself is suitable for spatial resolution. For example, fluorescence spectroscopy or infrared spectroscopy is considered as an optical or spectroscopic method. These methods can be used in combination with backscattering methods. Ellipsometry is also considered as a measuring method. Camera-based measurement methods can also be used within the scope of the present invention. However, within the scope of the present invention, a particularly advantageous measuring method is laser-induced fluorescence spectroscopy.

[0040] Within the scope of the invention, optical or spectroscopic measurements, in particular laser-induced fluorescence spectroscopy measurements, are performed on the substrate surface or metal surface, which measurements reflect the local lubricant situation. An analysis parameter can be extracted from the measurement results by data processing, which analysis parameter is referred to as the second analysis parameter hereinafter. The second analysis parameter describes the lubricant position after the lubricant has been applied to the metal plate. The following second analysis parameters can be determined based on the measurement results of at least one sensing unit: absolute lubricant coverage, spatially averaged lubricant coverage, spatially resolved lubricant distribution, average layer thickness of the applied lubricant, spatially resolved layer thickness distribution of the lubricant or a parameter proportional thereto. This list is not exhaustive. These values ​​can be determined mathematically, empirically using an evaluation algorithm or with the aid of an evaluation program.

[0041] A particular advantage of the invention results from the fact that not only the local lubricant situation on the base plate or metal plate but also internal process parameters or operating parameters of the machine are taken into account when regulating the machine.

[0042] For example, the machine comprises at least one pump unit, which is connected to at least one coating unit via at least one conveyor line. The pump unit can be assigned at least one measuring unit, which can be arranged directly on the pump unit or alternatively in the region of the conveyor line. At the same time, a plurality of interacting sensors can also form the measuring unit. The individual sensors can be arranged at different locations of the at least one pump unit or at least one conveyor line.

[0043] By means of at least one measuring unit, a first analysis parameter can be determined, which is used to characterize the flow of the lubricant in the direction of the coating unit. Alternatively, the first analysis parameter can be determined based on machine parameters (e.g., the set speed of the pump unit). The machine parameters can be determined either by a separate unit or by a control unit or a data processing unit. For example, when input by a user, the machine parameters can be directly converted into the corresponding second analysis parameters. Units or microcontrollers for determining machine parameters and converting them into first analysis parameters can also be provided in different machine components. These first analysis parameters can then be transmitted to the data processing unit. The data processing unit can also calculate the first analysis parameters directly based on the machine parameters. The first analysis parameter can be the following parameters: the absolute flow of the lubricant, the time or space average flow of the lubricant, the volume flow of the lubricant, the flow velocity of the lubricant, the viscosity of the lubricant, the pump pressure, the pump rate or a parameter proportional thereto. This list is not exhaustive.

[0044] The second analysis parameter is characterized in that it is measured on the one hand to control the process performance and on the other hand it can be at least partially adjusted (i.e. regulated) by the control unit. In contrast, since the second analysis parameters reflect the local lubricant situation on the substrate or metal sheet, they cannot be adjusted directly by the control unit. These indicators can only be influenced indirectly.

[0045] The consideration of the local lubricant situation on the substrate or metal sheet and the internal machine parameters is expressed as follows: Using the data processing unit, at least one quality parameter is calculated from at least one first analysis parameter and at least one second analysis parameter. The quality parameter thus takes into account both the local lubricant situation and the measured values ​​of the pump unit or the machine parameters, thereby providing a reliable basis for the assessment of the process quality and ultimately the quality of the lubricant coating on the substrate or metal sheet. Insufficient lubricant coating can often be due to local inhomogeneities of the substrate or metal sheet or to certain control or regulation parameters of the machine that cannot be adequately adapted to the requirements of the lubricant coating on the respective substrate or metal sheet. This fact is taken into account when calculating the quality parameter by taking into account the first and second analysis parameters.

[0046] At least one quality parameter calculated in this way is compared with at least one first default parameter. The default parameter can be an absolute value. The default parameter can also include a limit range or a tolerance range in which the quality parameter is allowed to move, so the default parameter can include a value range. If the determined quality parameter deviates from the default parameter (the deviation may come from the deviation of the quality parameter relative to the absolute value or from the quality parameter falling outside the value range), a negative determination is made as a result of the comparison. Due to the negative determination, one or more setting parameters of the machine can be checked and / or changed by the control unit. The check is preferably performed in an automated manner, but can also be performed semi-automatically or manually. As part of the check, for example, the following setting parameters can be checked and compared with the set values: the gap width of the discharge port, the strength or orientation of the electric field, the duty cycle of the electric field, the absolute flow rate of the lubricant, the time or space average flow rate of the lubricant, the volume flow rate of the lubricant, the flow rate of the lubricant, the pump pressure, the pump rate, and the coating temperature of the lubricant.

[0047] It should be noted that some of the setting parameters listed here may also represent first analysis parameters at the same time. These parameters can therefore be simultaneously changed by the control unit and can be measured by the measuring unit assigned to the pump unit. Internal system errors of the machine can also be detected by the check. In the case of a system error, it may be necessary to check the machine manually. In the case of a system error, the function of the machine can also be realized by the check routine. If there is no system error, this is signaled to the control unit and the lubricant application is continued or a positive decision is made.

[0048] After the inspection (depending on the inspection results), the lubricant application can be continued on other substrates or metal sheets without changing the parameters. If the lubricant is applied to a metal strip which is wound into a coil after the lubricant application, the locations where the lubricant application is insufficient can be marked or declared as scrap. It is also possible to declare the entire metal strip as scrap. In the case of partial marking of insufficient lubricant application, the lubricant application can be repeated manually or automatically at this location.

[0049] Within the scope of the method according to the invention, the coating process can also be interrupted in order to automatically or manually change certain setting parameters. The parameter change can be carried out using an algorithm and, if necessary, can be repeated. As a result of the change, the lubricant coating can be repeated on the same substrate or metal sheet (if necessary with prior cleaning), or the lubricant coating can be carried out on new substrates or metal sheets introduced into the machine.

[0050] When making an affirmative determination, the calculated quality parameter corresponds to a default parameter or falls within the value range used to define the default parameter. In order to further improve reliability and accuracy in the assessment of process quality, another control loop can be traversed even in the case of an initial affirmative determination. However, the method can also be designed not to pass through the control loop. In the latter case, the substrate or metal plate is released after the affirmative determination and can be further transported in the conveying direction. If the control loop is traversed, another first and / or second analysis parameter is compared with the second default parameter. Here, preferably, the spatially resolved lubricant distribution determined by an optical or spectroscopic measurement method (e.g., laser induced fluorescence spectroscopy) is compared with the second default parameter. The spatially resolved lubricant distribution of different lubricants can also be compared with the second default parameter. The second default parameter can also include an absolute value or a value range. Alternatively, the second default parameter can include one or more data curves, such as a lubricant distribution as a function of position, wherein the position in this case includes a position axis extending laterally along the substrate or metal plate or relative to the substrate or metal plate.

[0051] After traversing the control loop, another negative or positive decision is made. In the case of a positive decision, the metal sheet is released. In the case of a negative decision, the substrate or metal sheet is declared as waste, or it is not released for further processing or further conveying, or the substrate or metal sheet is cleaned and then reintroduced into the machine for lubricant application.

[0052] The method according to the invention is therefore a closed loop in terms of control technology. Depending on whether a positive or negative decision is made in step f of the method according to the invention, the method automatically runs through the control loop, checks internal machine parameters and / or setting parameters and, if necessary, changes them before executing a new method cycle. The process is therefore suitable for automatic control of the machine and in this case takes into account the current process performance in terms of lubricant application (e.g., type and purity of the applied lubricant) and machine parameters.

[0053] The measuring unit assigned to the pump unit can be, for example, a flow sensor. In particular, direct volume flow meters (e.g. drum flow meters, oval gear flow meters, piston flow meters), indirect volume flow meters (e.g. propeller flow meters), float flow meters, magnetic induction flow meters, inductive flow meters, ultrasonic flow sensors, Coriolis mass flow meters, vortex flow meters, correlation flow meters, laminar flow meters, flow probes, thermal mass flow meters, laser Doppler and spectroscopy systems come into consideration. As a spectroscopic measuring method, for example, flow measurements based on nuclear magnetic resonance come into consideration. A pressure meter can also form the measuring unit.

[0054] As described above, the second analysis parameter is determined by at least one sensing unit. The at least one sensing unit is suitable for performing an optical or spectroscopic measuring method, for example for performing spatially resolved laser induced fluorescence spectroscopy. The sensing unit can be integrated into the machine. Preferably, a plurality of sensing units are integrated into the machine, wherein the sensing units are advantageously arranged above and / or below the metal plate. When using a measuring method based on laser induced fluorescence spectroscopy, at least one sensing unit is equipped with a solid-state laser, by which up to 10,000 laser pulses per second can be generated. The use of such short pulses or the use of such a pulse frequency is advantageous because a higher spatial resolution is thereby produced compared to longer pulses used when the belt is moved at a constant belt speed.

[0055] The energy of the laser pulse is transmitted via a quartz fiber bundle in the direction of the measurement position, i.e. in the direction of the substrate surface or metal surface. The individual photons of the fluorescence signal emitted from the substrate surface or metal surface with lubricant are detected by a photomultiplier tube and a second quartz fiber bundle. After the measurement or at defined time intervals, the probe of the sensing unit is purged with compressed air. This is because, since the sensing unit is directly mounted on the machine, the quartz fiber bundle or the probe can be contaminated by the spray coming out of the spray chamber. After purging, a reference measurement of the calibration sample can be performed. For laser-induced fluorescence measurements, the sensing unit must maintain a working distance that is as constant as possible relative to the substrate surface or metal surface. In this case, a tolerance range of ±20 mm has proven to be sufficient.

[0056] Furthermore, the sensing unit can include a counting system which detects individual photon times in the nanosecond range. The data detected in this way can be evaluated using a data processing unit. For this purpose, the data processing unit is connected to the sensing unit in terms of signal transmission. The sensing unit can also include a microcontroller, by means of which a preliminary evaluation of the detected measured values ​​can be performed. Parameters which can be quantitatively determined using laser-induced fluorescence spectroscopy are, for example, the weight per unit area of ​​the lubricant coating in g / m 2 The LIFS measurement depends on the lubricant type. This is an important property in order to determine the presence of a lubricant mixture or multiple lubricants on a substrate or metal sheet and resolve them spatially. Other optical or spectroscopic measurement methods may also be applicable to determine the weight per unit area of ​​the lubricant coating and provide an indication of the presence of multiple lubricants on a substrate or metal sheet.

[0057] The spatial resolution of various measurement parameters, such as a lubricant coating on a substrate or metal sheet, can also be detected by means of the sensing unit. For this purpose, the sensing unit is arranged on a traversing unit which extends beyond the metal sheet transversely with respect to the conveying direction of the metal sheet. The sensing unit is moved along the traversing unit to different measuring positions and records measurement signals at the different positions. The spatially resolved measurement signals are transmitted to a data processing unit.

[0058] Other advantages of the present invention will be described in more detail below.

[0059] According to an advantageous embodiment of the invention, the machine is integrated in a production line and / or a conveyor line for substrates or metal sheets, for example in a rolling mill or a punching machine. By integrating the machine into a production line or a conveyor line for substrates or metal sheets, it is not necessary to remove it from the production line or conveyor line for the application of lubricant. Thus, the process can be carried out continuously. This is particularly advantageous for longer metal strips. Process and production costs can be saved by this integrated design. In addition, the quality of the lubricant application can therefore be determined immediately after the lubricant has been applied to the substrate or metal sheet, thereby avoiding the lubricant melting during the transport to the sensing unit and influencing the measurement result.

[0060] According to another embodiment of the present invention, the coating unit includes an upper coating module and / or a lower coating module, wherein each coating module includes at least one discharge port through which the lubricant passes in the direction of the substrate or metal plate. It is determined on which side the lubricant is applied to the substrate or metal plate according to customer requirements. For metal strips, since the metal plate contacts the other surfaces of the metal strip on both sides when it is wound into a coil, it is advantageous to apply lubricants on both sides thereof. Therefore, mechanical damage to the metal plate (for example, due to friction) can be reduced on both sides. If the lubricant is applied to the upper and lower sides of the substrate or metal plate, the machine is provided with at least one coating unit arranged above the substrate or metal plate and at least one coating unit arranged below the substrate or metal plate. Therefore, when applying the lubricant, the substrate or metal plate can be arranged between the upper coating module and the lower coating module.

[0061] The types of coating units can be divided essentially into different coating types. This division can be divided into pneumatic coating, i.e. spraying the substrate with the lubricant under the action of compressed air, and electrostatic coating. In the case of electrostatic lubricant coating, an electric field is applied to the lubricant before, during or after it passes through the outlet opening. Thus, depending on the type of coating, the lubricant droplets are formed by the action of compressed air in combination with a corresponding adjustment of the gap width of the outlet opening or by the action of an electric field.

[0062] In order to apply the lubricant, the machine can include a spray chamber, into which the coating unit is integrated. The individual coating modules can be spray bars in which at least one outlet for the lubricant is provided. The spray bar can be integrated into the spray chamber. In addition, such a spray bar can also be designed without a spray chamber. In the case of electrostatic oiling, the lubricant is not supplied by compressed air, but is applied by an electric field. In the case of compressed air-based oiling, the lubricant is transported through the corresponding outlets under compressed air. In principle, both methods (electrostatic oiling, pneumatic oiling) can be considered to be carried out in a spray chamber or without a spray chamber. In addition, corresponding spray bars can be provided for both methods.

[0063] The coating unit can also be designed for spot application of oil. For this purpose, the coating module belonging to the coating unit can only include a single outlet through which the spot application of oil can be carried out. However, spot application of oil can also be carried out by providing a plurality of outlets in the coating module. With the method according to the invention, the individual outlets can be controlled and the control parameters can be adjusted for the individual outlets.

[0064] According to an advantageous embodiment, the application module can be a nozzle system in which at least one outlet opening for the lubricant is provided in the form of a nozzle. Depending on the type of lubricant application, the nozzle system can be combined with a compressed air supply or an external electric field.

[0065] Furthermore, it is advantageous to apply the lubricant to the substrate or metal plate in the form of a spray, either by electrostatic lubricant application or by pneumatic lubricant application.

[0066] For the application of lubricant, the substrate or metal sheet is guided through at least one coating module of a coating unit, whether electrostatic or pneumatic.

[0067] In the case of electrostatic lubricant coating, the lubricant droplets are charged when they emerge from the discharge opening and are accelerated in the direction of the substrate surface or metal surface. The electric field can be variably adjusted, for example in terms of its orientation, strength or propagation time.

[0068] According to another embodiment of the present invention, the temperature of the lubricant can be increased to the coating temperature in a stepped waterfall manner before coating. It is also conceivable to increase the temperature linearly or once before the lubricant is input into the pipeline system. This temperature increase may be advantageous in that the fluidity of the lubricant is increased in a temperature-increasing manner. The increased fluidity can promote the delivery of the lubricant from a storage container via a pipeline system connected to a pump to at least one coating unit. As the temperature increases, the dynamic viscosity of the lubricant decreases according to the Arrhenius-Andrade relationship. The increase in the temperature of the lubricant can also promote the fine distribution of the spray on the coating unit or on a coating module including a discharge port.

[0069] According to another embodiment of the present invention, multiple discharge ports or nozzles can be arranged above and / or below the substrate or metal plate, so that complete spraying can be achieved over the entire width of the metal plate. The number of discharge ports or nozzles provided can vary depending on the size of their spray area. If a discharge port or nozzle with a smaller spray area is used (the spray area defines the size of the area of ​​the substrate or metal plate that can be exposed to the lubricant from a single discharge port or nozzle), a larger number of discharge ports or nozzles must be used to coat the substrate or metal plate over the entire width of the substrate or metal plate compared to the case of using a discharge port or nozzle with a larger spray area. The gap width of the discharge port or nozzle can be changed mechanically, for example by a small slide, a bolt assembly, a metal hoop or a solenoid valve.

[0070] According to a further advantageous embodiment of the method according to the invention or of the device according to the invention, the lubricant can be applied to the substrate or metal plate in the form of a spray.

[0071] In the case of pneumatic lubricant application, the lubricant can be mixed with the gaseous fluid under pressure as it passes through the discharge port, or shortly before or after. For example, as a fluid, consider compressed air or CO 2 .

[0072] The spray quantity or spray fineness can be adjusted by changing the gap width of the discharge port. The larger the gap width, the more lubricant can pass through the nozzle per unit time. The smaller the gap width, the finer the distribution of the lubricant, i.e., the smaller the gap width, the smaller the droplet size. This adjustment works not only in electrostatic lubricant application, but also in pneumatic lubricant application.

[0073] As described above, the lubricant can be exposed to an electric field before and / or after passing through at least one discharge port, wherein the spray volume or spray fineness is adjusted by the intensity or orientation of the electric field. In the case of an electric field or an electrostatic field when coating a substrate or a metal plate with lubricant droplets, these droplets are electrostatically charged. When they hit the metal surface, droplets that are uniformly distributed but spaced apart from each other are formed on the metal surface. The spacing of the droplets is caused by the droplets charged with the same sign of charge and the particle repulsion that accompanies it. Since all droplets with the same charge try to repel each other, the electrostatic charge is preferably located on the droplet surface when the droplets are sprayed. Using the electric field, the droplets can be evenly and finely distributed on the metal surface. In addition, the electrostatic charge causes a strong bond between the particles and the metal plate surface. The metal plate can be grounded and therefore has a polarity opposite to the polarity of the charge on the droplets. In addition, the electrostatic charge causes a strong bond between the particles and the metal plate surface. The metal plate can be grounded and therefore has a polarity opposite to the polarity of the charge on the droplets. In addition, the electrostatic charge causes a strong bond between the particles and the metal plate surface. The metal plate can be grounded and therefore has a polarity opposite to the polarity of the charge polarity of the droplets.

[0074] According to another advantageous embodiment of the present invention, the control unit is connected to the coating unit, the pump unit and the sensing unit in terms of signal transmission. It is thereby ensured that the central control unit of the machine can transmit control commands to the coating unit, the pump unit and the sensing unit. For example, in step g) of the method according to the present invention, after a negative determination, a command for changing a setting parameter (e.g., a change in the pump rate or the gap width of the discharge port) is output to the pump unit or the coating unit. At the same time, the signal connection ensures that data is transmitted between the various components of the machine. The control unit can also receive signals and data from the coating unit, the pump unit and the sensing unit.

[0075] Within the scope of the present invention, it may be advantageous to integrate the data processing unit into the control unit. Alternatively, the data processing unit can be designed to be separated from the control unit and connected to the control unit in terms of signal transmission. The integrated design of the data processing unit and the control unit saves space on the one hand, and on the other hand, there is no need to provide a signal connection between the two components, or the signal connection can be realized on a common printed circuit board. In addition, a microcontroller is arranged on various components of the machine (i.e., for example on a pump unit, a coating unit, and a measuring unit and a sensing unit), which are connected to the control unit signal, receive signals from the control unit and execute commands. At the same time, the microcontroller can send signals in the direction of the control unit.

[0076] Furthermore, it is advantageous if the data processing unit and / or the control unit are connected to the measuring unit and the sensing unit in terms of signal transmission. This is because the measuring unit and the sensing unit must also be controlled to perform the measurement. At best, this is done in coordination with other process parameters. Because in the idling state of the machine, for example, optical or spectroscopic measurements do not have to be performed. Similarly, when the lubricant application is stopped and no lubricant is supplied to the application unit, it is not necessary to perform flow measurements with the measuring unit. Such process events are controlled by the control unit or the data processing unit and transmitted to the measuring unit and the sensing unit. In particular, the start, end and duration of the measurement to be performed are controlled by the data processing unit and / or the control unit. This can also be done in conjunction with a microcontroller provided on the sensing unit and the measuring unit.

[0077] According to another advantageous embodiment of the invention, at least one sensing unit is arranged on a traversing device so as to be movable relative to the metal plate, the traversing device being arranged above and / or below the substrate or the metal plate. This enables spatially resolved optical or spectroscopic measurements, such as laser induced fluorescence spectroscopy. Here, the surface of the substrate or the metal plate can be scanned by moving the sensing unit on the traversing device, in the case of laser induced fluorescence spectroscopy, the measuring range corresponding to the focus of the laser spot emitted from the quartz fiber bundle. The traversing device can be designed as a single axis or multi-axis. Preferably, a single-axis embodiment enables the sensing unit to be moved transversely relative to the conveying direction of the substrate or the metal plate. The traversing device can include a holding element for the sensing unit, by which the sensing unit can be moved along a running track extending transversely relative to the metal plate. Thus, the sensing unit is preferably movable over the entire width of the metal plate. In principle, additional movability in the conveying direction of the metal plate and additional height adjustability can also be considered. The sensing unit or the holding element can be guided along the running track of the traversing device by a track device or a roller device. An arrangement on a linear unit is also possible. Furthermore, the holding element of the traversing device can be designed as a carriage supporting the sensing unit. The traversing speed is preferably 0.5-1 m / s. This makes it possible to have a spatial measurement resolution of 5 mm. Alternatively, the sensing unit can be arranged above or below the substrate or metal plate in a fixed position, i.e., there is no movable device on the traversing device. In this case, the sensing unit can detect the entire width of the substrate in a metered manner.

[0078] As already described elsewhere, the first analysis parameter according to a further advantageous embodiment of the invention is selected from the following group: absolute flow of lubricant, time- or space-averaged flow of lubricant, volume flow of lubricant, flow velocity of lubricant, viscosity of lubricant, pump pressure, pump rate or a parameter proportional thereto. This list is not exhaustive. The listed analysis parameters can be determined using a measuring unit arranged in the area of ​​the pump unit or the conveyor line. It is also possible to provide a plurality of measuring units for measuring different first analysis parameters. Furthermore, the first analysis parameter can be determined or derived from the first machine parameter.

[0079] As has also been described elsewhere, the second analysis parameter can be selected from the group consisting of the absolute lubricant coverage, the spatially averaged lubricant coverage, the spatially resolved lubricant distribution, the average layer thickness of the applied lubricant, the spatially resolved layer thickness distribution of the lubricant or a parameter proportional thereto. The second analysis parameter is determined optically or spectroscopically (e.g. by laser induced fluorescence spectroscopy). The sensor unit provided for this purpose is moved over the substrate or metal sheet by means of a traversing device and records the measurement data at different positions. For the spatial representation, the measurement data recorded at different positions or the values ​​extracted therefrom can be plotted on a position axis (e.g. the width of the substrate or metal sheet).

[0080] According to another embodiment of the invention, the first and / or second analysis parameter can represent a spatially or temporally resolved data curve or a value extracted from a data curve. The second analysis parameter is preferably sensed in a spatially resolved manner, i.e. by a sensing unit that can be moved relative to the substrate or metal plate via a traversing device. Thus, the data determined in this way can be represented spatially resolved in the form of a data curve with a relatively small amount of effort, for example as a lubricant coverage or layer thickness displayed over the entire width of the substrate or metal plate. Thus, the distribution function of certain parameters can be determined in a relatively simple manner. With regard to the first analysis parameters, it may be useful to record them within a specific time range, for example during the application of the lubricant to the substrate or metal plate.

[0081] According to an advantageous embodiment of the invention, the quality parameter is calculated based on the sum, difference, product, quotient or other of the first and second analysis parameters. In particular, it has proven to be advantageous to calculate the quality parameter based on the quotient between the first and second analysis parameters. In particular, the quotient determined by the spatial average lubricant coverage and the flow rate or a value proportional thereto can prove to be a meaningful quality parameter. According to the invention, the quality parameter of step f) of the method on which the invention is based is compared with a first default parameter. This has been described in detail above. The first default parameter can be determined mathematically or empirically, for example based on empirical values ​​or machine characteristic data. Here, the type, size and thickness of the substrate or metal plate and the lubricant can also be taken into account.

[0082] Furthermore, a first default parameter can be manually specified, wherein it preferably assumes the value 1. In particular, when using a quotient determined from the spatially averaged lubricant coverage and the flow rate or a value proportional thereto, it has been shown that a default parameter of 1 is advantageous. If the quotient deviates greatly from the default value 1, i.e., outside a tolerance range or a limit range, this may indicate that there is too much or too little lubricant on the metal sheet. In this case, as described above, at least one setting parameter is automatically checked and / or changed by the control unit. If the determined quality parameter corresponds to the default parameter, an additional control loop can be passed and / or the metal sheet can be released for further conveying or further processing.

[0083] Of decisive importance for the adequate determination of a quality parameter, for example the ratio of the lubricant coating based on the amount of lubricant applied (which can be determined, for example, from the flow rate in process step b) to the measured coating value (which can be determined, for example, by optical or spectroscopic measurement using a sensing unit in process step d), is that the amount of oil determined in the flow reaches the belt as completely as possible. Here, edge losses (overspray) caused by the curved field lines of the electrostatic field must be taken into account. For different widths of the substrate or metal sheet, such losses can be reduced by means of segmented oil beams adapted to the corresponding bandwidth. According to an advantageous embodiment of the invention, the side losses can be numerically estimated and corrected accordingly. Such a correction factor can be included in the calculation of the quality parameter.

[0084] According to another embodiment of the invention, the setting parameter is selected from the following group: gap width of the discharge port, strength or orientation of the electric field, duty cycle of the electric field, air pressure, absolute flow rate of lubricant, time or space average flow rate of lubricant, volume flow rate of lubricant, flow rate of lubricant, pump pressure, pump rate, application temperature of lubricant. This list is not exhaustive and may include other setting parameters of the machine. The setting parameter can be changed depending on the type of lubricant application (e.g. electrostatic or pneumatic). In the case where the lubricant coverage is determined to be too high by the quality parameters and the default parameters, for example, the pump rate as a setting parameter can be reduced (i.e., modified). In contrast, if the lubricant coverage is too low, the pump rate as a setting parameter can be increased.

[0085] According to a further advantageous embodiment of the invention, when executing the control loop, a further first or second analysis parameter is compared with the second default parameter. Thereby, an additional evaluation of the current lubricant situation on the metal sheet can be performed. For example, after comparing the quality parameter with the first default parameter, additional information about the current lubricant situation on the substrate or metal sheet can be obtained. In particular, it may be useful not to take into account spatially resolved values ​​(e.g. lubricant coverage) when comparing the quality parameter with the first default parameter, but only average values. The spatial distribution of certain first analysis parameters can then also be taken into account by the control loop.

[0086] According to another advantageous embodiment of the invention, the second default parameter can be a mathematically, empirically or metrologically determined nominal value or a nominal curve for the first or second analysis parameter. For example, a characteristic nominal value or a nominal curve for the first or second analysis parameter can be considered for a specific type, size and desired lubricant loading. This can be based on empirical values ​​or calibration measurements. The results of the calibration measurements or the nominal values ​​or nominal curves can be stored in an electronic data directory and retrieved by the data processing unit or the control unit when necessary.

[0087] According to another embodiment of the invention, after executing the control loop, another negative or positive decision is made, wherein, in the case of a positive decision, the substrate or metal sheet is released. The advantages of this aspect have already been explained above. In the case of a negative decision, the substrate or metal sheet is preferably declared as waste, or the substrate or metal sheet is cleaned and coated with lubricant again. In the case of a positive decision, the substrate or metal sheet is released for further transport or further processing.

[0088] The method according to the invention and the device according to the invention can be used with all the advantageous configurations described above, wherein the features described can be present individually or in any combination.

[0089] In addition, it should be pointed out that terms such as "comprising", "having" or "with" do not exclude other features or steps. Furthermore, the terms "a" or "the" indicating an individual step or feature do not exclude a plurality of features or steps, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0090] Further advantages of the invention are explained by the use of exemplary embodiments based on individual aspects of the method according to the invention and of the device according to the invention.

[0091] Figure 1 A perspective view showing a detail of a sensing unit as part of a machine for applying lubricant to metal sheets.

[0092] Figure 2A schematic diagram showing the main components of a machine for applying lubricant.

[0093] Figure 3 A schematic diagram of the process flow according to the present invention is shown. Specific embodiments

[0094] For example, the invention is explained by using the example of a metal plate 2 as a substrate. However, the method according to the invention and the device according to the invention are not limited to use with metal plates. In addition, the following is also based on the example of electrostatic application of a lubricant. However, this does not limit the invention to this type of lubricant application.

[0095] Figure 1 A detail of a sensing unit 7 is shown in a perspective view, which belongs to a machine 1 for applying a lubricant 10 to a substrate or metal sheet 2. This type of machine 1 is also called an oiler or oiler. Such an oiler 1 can be integrated into a production line and / or a conveyor line for metal sheets 2, for example in a rolling mill or a punching machine. In such a production line and / or a conveyor line, the metal sheets 2 (and additionally also metal strips) move along a conveying axis A.

[0096] For the application of lubricant 10, the metal sheet 2 passes through a chamber of the machine 1. The chamber may be a spray chamber 11. The metal sheet 2 is introduced into the machine 1 or the spray chamber 11 from one side. After the lubricant 10 has been applied to the metal sheet 2, the metal sheet 2 is led out of the chamber 11. The transport of the metal sheet 2 along the transport axis A may be carried out, for example, by a conveyor belt or conveyor rollers.

[0097] In the spray chamber 11, a coating module comprising a coating unit with one or more discharge openings, through which the lubricant 10 is conveyed in the direction of the metal sheet 2, can be arranged above and / or below the metal sheet 2. Preferably, an electric field is located downstream of the discharge opening, by which a uniform droplet distribution of the lubricant 10 on the surface of the metal sheet 2 is ensured.

[0098] As explained later, the lubricant loading or the homogeneity of the applied lubricant 10 can be checked on the surface of the metal sheet 2 by means of the sensor unit 7 when exiting the spray chamber 11. In this case, analysis parameters such as the absolute lubricant coverage, the spatially averaged lubricant coverage, the spatially resolved lubricant distribution, the average layer thickness of the applied lubricant 10, the spatially resolved layer thickness distribution of the lubricant 10 or parameters proportional thereto can be determined.

[0099] The sensing unit 7 is an optical or spectroscopic system for performing optical or spectroscopic measurements. For example, it may be a system for performing laser induced fluorescence spectroscopy, to which reference will be made further below. Figure 1As shown, the sensing unit 7 can be arranged above and below the metal plate 2. The sensing unit 7 can be moved transversely relative to the conveying axis A of the metal plate 2 by a traversing device 12. The traversing device 12 may include a holding element 13 for the sensing unit 7 and a running track 14, along which the holding element 13 can be moved. In order to measure the above parameters, the sensing unit 7 is moved transversely relative to the conveying axis A of the metal plate 2 and fluorescence spectroscopy measurements are performed at multiple positions. The traversing device 12 and the sensing unit 7 are arranged on the machine 1 outside the spray chamber 11. Due to the ubiquitous electric field, an arrangement inside the spray chamber 11 should be avoided.

[0100] Figure 2 The main components of a machine 1 used within the scope of the method according to the invention are shown in a schematic diagram. The machine 1 thus comprises a pump unit 5, by means of which a lubricant 10 is conveyed via a conveyor line 4 (indicated by an arrow) in the direction of a coating unit 3. The pump unit 5 can be connected to a lubricant reservoir, for example a lubricant tank. The pump unit 5 can also be connected to a plurality of lubricant reservoirs. Via these mutually separate lubricant reservoirs, different lubricants 10 can be applied successively to one or more substrates or metal sheets 2. The lubricant 10 is applied to the metal sheet 2 via a coating unit 3, which can, for example, comprise a nozzle system or a coating module consisting of a plurality of outlet openings. Here, due to the application of the lubricant, a film of lubricant 10 is formed on the metal sheet 2. As shown in FIG. Figure 2 It is also shown that the measuring unit 6 can be connected to the pump unit 5 or the delivery line 4 or can be arranged on these components in order to carry out flow measurement.

[0101] Furthermore, the machine 1 is provided with a sensor unit 7, by means of which the application of lubricant to the metal sheet 2 can be checked. Preferably, the sensor unit 7 is a device for performing laser induced fluorescence spectroscopy. In this way, for example, the lubricant loading or the layer thickness of the applied lubricant 10 can be measured. The pump unit 5, the application unit 3, the measuring unit 6 and the sensor unit 7 exchange signals with a control unit 8. The components can also exchange signals with a data processing unit 9. The control unit 8 and the data processing unit 9 can be designed as a common component.

[0102] exist Figure 3 The main method steps of the method according to the invention are schematically described in FIG. First, certain default parameters are set or determined by the user or automatically. Thereafter, starting from the pump unit 5, at least one lubricant 10 is conveyed or pumped in the direction of at least one coating unit 3 (step a). The conveying of the lubricant 10 can take place via one or more conveying lines 4.

[0103] In method step b, a first analysis parameter is measured by at least one measuring unit 6 arranged on the pump unit 5 or the conveying line 4, or the first analysis parameter is determined according to a machine parameter. The first analysis parameter can be determined by at least one measuring unit 6, which is used to characterize the flow of the lubricant 10 in the direction of the coating unit 3. The first analysis parameter can be the following parameters: the absolute flow rate of the lubricant 10, the time or space average flow rate of the lubricant 10, the volume flow rate of the lubricant 10, the flow rate of the lubricant 10, the viscosity of the lubricant 10, the pump pressure, the pump rate or a parameter proportional thereto. This list is not exhaustive. After starting the pumping process, the measuring unit 6 can continuously record the measured values ​​during pumping. Alternatively, the first analysis parameter can be determined according to a machine parameter (for example, the rotation speed of the pump unit 5).

[0104] In method step c, the lubricant 10 conveyed in the direction of the coating unit 3 is applied to at least one side of the metal sheet 2, but preferably to both sides of the metal sheet 2. For this purpose, preferably, a discharge opening or a nozzle is provided in the coating unit 3, through which the lubricant 10 is applied to the metal sheet 2 in the form of droplets in the sense of a spray.

[0105] According to method step d, at least one second analysis parameter is measured with the sensing unit 7. The second analysis parameter reflects the lubricant position after the lubricant 10 has been applied to the metal sheet 2. The following second analysis parameters can be determined based on the measurement results of the at least one sensing unit 7: absolute lubricant coverage, spatially averaged lubricant coverage, spatially resolved lubricant distribution, average layer thickness of the applied lubricant 10, spatially resolved layer thickness distribution of the lubricant 10 or a parameter proportional thereto. This list is not exhaustive.

[0106] In the subsequent method step e, at least one quality parameter is calculated from the at least one first analysis parameter and the at least one second analysis parameter using the data processing unit 9. The quality parameter takes into account not only the local lubricant situation but also the measured values ​​of the pump unit 5 and thus provides a reliable basis for the assessment of the process quality and ultimately the quality of the lubricant application on the metal sheet 2. Lubricant losses such as overspray can also be taken into account.

[0107] In method step f, the calculated at least one quality parameter is compared with at least one first default parameter. If the determined quality parameter deviates from the default parameter, a negative decision is made as a result of the comparison. Due to this negative decision, one or more setting parameters of the machine can be checked and / or changed by the control unit (step g).

[0108] The inspection is preferably performed in an automated manner, but can also be performed semi-automatically or manually. As part of the inspection, for example, the following setting parameters can be checked and compared with the rated values: the gap width of the nozzle, the electric field strength, the duty cycle of the electric field, the absolute flow rate of the lubricant 10, the time or space average flow rate of the lubricant 10, the volume flow rate of the lubricant 10, the flow rate of the lubricant 10, the pump pressure, the pump rate, the coating temperature of the lubricant. After checking or changing the setting parameters, the lubricant can continue to be applied to a new metal plate 2, or the lubricant can be repeatedly applied to a previously coated metal plate 2 after cleaning. The inspected metal plate 2 can also be declared as waste and removed from the conveying or production process. Thus, a closed control circuit (closed loop) is ensured, which automatically continues after the process steps have been performed and can be flexibly adapted to the current conditions, which to a certain extent means a self-learning process.

[0109] When a positive determination is made (also in step f), the calculated quality parameter corresponds to a default parameter or falls within the range of values ​​used to define the default parameter. Here, a tolerance range can be taken into account. In order to further improve reliability and accuracy in the assessment of process quality, even in the case of an initial positive determination, another control loop can be traversed (step g). However, the method can also be designed not to traverse this control loop. In the latter case, the metal sheet 2 is released after the positive determination (step g) and can be further conveyed in the conveying direction. If the control loop is traversed, another first and / or second analysis parameter is compared with the second default parameter.

[0110] After traversing the control loop, a further negative or positive decision (not shown) is made. A positive decision can also be made if a further first and / or second analysis parameter does not completely correspond to the second default parameter, but is within a predetermined tolerance range or limit range. In the case of a positive decision, the metal sheet 2 is released. In the case of a negative decision, the metal sheet 2 is declared as waste and is not released for further processing or further transport, or the metal sheet 2 is cleaned and subsequently fed back into the machine 1 for lubricant coating.

[0111] Reference numerals list

[0112] 1 Machine

[0113] 2 Metal Plates

[0114] 3 coating units

[0115] 4Conveyor lines

[0116] 5 pump units

[0117] 6 measuring units

[0118] 7 Sensing Unit

[0119] 8 control units

[0120] 9Data processing unit

[0121] 10. Lubricant

[0122] 11Spray Room

[0123] 12 Traverse device

[0124] 13. Holding element

[0125] 14 Running Tracks

[0126] A conveying axis

Claims

1. A method for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate, wherein: The machine (1) comprises at least one coating unit (3), at least one pump unit (5) connected to the at least one coating unit (3) via at least one conveying line (4), at least one sensing unit (7) for performing a spatially resolved optical or spectroscopic measurement method, and a data processing unit (9), the method comprising the following steps: a. using the at least one pump unit (5): conveying the lubricant (10) via the at least one delivery line (4) in the direction of the at least one coating unit (3); b. measuring at least one first analysis parameter by means of at least one measuring unit (6) assigned to the at least one pump unit (5), or determining the at least one first analysis parameter as a function of a machine parameter, wherein the at least one measuring unit (6) is arranged directly at the at least one pump unit (5) or alternatively in the region of the at least one conveying line (4), and wherein the first analysis parameter characterizes the flow of the lubricant towards the coating unit (3); c. using the at least one coating unit (3): applying the lubricant (10) to at least one side of the substrate; d. measuring at least one second analysis parameter related to the lubricant distribution using the sensing unit (7), wherein the sensing unit (7) is arranged above and / or below the substrate; e. using the data processing unit (9): calculating at least one quality parameter; f. using the data processing unit (9): comparing the at least one quality parameter with at least one first default parameter, wherein, as a result of the comparison, a positive or negative determination is made; g. in the case of a negative determination: automatically checking and / or changing at least one setting parameter via a control unit (8) included in the machine (1); and in the case of a positive determination: executing a control loop and / or releasing the substrate, wherein, in step e, the at least one quality parameter is calculated based on the at least one first analysis parameter and the at least one second analysis parameter, Wherein, during the automatic checking process in step g, system errors of the machine are detectable.

2. The method according to claim 1, characterized in that The coating unit (3) has a lower coating module and / or an upper coating module, wherein each coating module comprises at least one discharge opening through which the lubricant (10) passes in the direction of the substrate.

3. The method according to claim 2, characterized in that When applying the lubricant (10), the substrate is arranged between the lower coating module and the upper coating module.

4. The method according to claim 1, characterized in that The first analysis parameter is selected from the following group: the absolute flow rate of the lubricant (10), the time- or space-average flow rate of the lubricant (10), the volume flow rate of the lubricant (10), the flow rate of the lubricant (10), the viscosity of the lubricant (10), the pump pressure, the pump rate, or a parameter proportional to the absolute flow rate of the lubricant (10), the time- or space-average flow rate of the lubricant (10), the volume flow rate of the lubricant (10), the flow rate of the lubricant (10), the viscosity of the lubricant (10), the pump pressure, or the pump rate.

5. The method according to claim 1, characterized in that The second analysis parameter is selected from the following group: absolute lubricant coverage, spatially averaged lubricant coverage, spatially resolved lubricant distribution, average layer thickness of the applied lubricant (10), spatially resolved layer thickness distribution of the lubricant (10), or a parameter proportional to the absolute lubricant coverage, the spatially averaged lubricant coverage, the spatially resolved lubricant distribution, the average layer thickness of the applied lubricant (10), or spatially resolved layer thickness distribution of the lubricant (10).

6. The method according to any one of claims 1 to 5, characterized in that The first analysis parameter and / or the second analysis parameter represent a spatially or temporally resolved data curve or values ​​extracted from the data curve.

7. The method according to any one of claims 1 to 5, characterized in that The quality parameter is calculated based on the sum, difference, product, or quotient of the first analysis parameter and the second analysis parameter.

8. The method according to claim 1, characterized in that The first default parameter is determined mathematically or empirically.

9. The method according to claim 1, characterized in that: The first default parameters are manually specified.

10. The method according to claim 9, characterized in that The first default parameter value is 1.

11. The method according to claim 2 or 3, characterized in that: The setting parameters are selected from the following groups: the gap width of the discharge port, the strength or orientation of the electric field applied to the lubricant, the duty cycle of the electric field, the air pressure, the absolute flow rate of the lubricant (10), the time or space average flow rate of the lubricant (10), the volume flow rate of the lubricant (10), the flow rate of the lubricant (10), the pump pressure, the pump rate, and the coating temperature of the lubricant (10).

12. The method according to any one of claims 1 to 5, characterized in that When executing the control loop, a further first analysis parameter or a further second analysis parameter is compared with a second default parameter.

13. The method according to claim 12, characterized in that The second default parameter is a mathematically, empirically or metrologically determined desired value or desired curve of the first analysis parameter or the second analysis parameter.

14. The method according to claim 12, characterized in that After executing the control loop, another negative determination or a positive determination is made as a result of comparing the another first analysis parameter or the another second analysis parameter with the second default parameter, wherein in case of a positive determination, the substrate is released.

15. The method according to any one of claims 1 to 5, characterized in that The substrate is a metal plate (2).

16. A device for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate, wherein: The machine (1) comprises: a. at least one coating unit (3) for coating the lubricant (10) on at least one side of the substrate; b. at least one pump unit (5) connected to the at least one coating unit (3) via at least one conveying line (4), for conveying the lubricant (10) in the direction of the at least one coating unit (3) via the at least one conveying line (4); c. at least one measuring unit (6) assigned to the pump unit (5) for measuring at least one first analysis parameter, or a unit for determining the at least one first analysis parameter as a function of a machine parameter, wherein the at least one measuring unit (6) is arranged directly at the at least one pump unit (5) or alternatively in the region of the at least one conveying line (4), and wherein the first analysis parameter characterizes the flow of the lubricant towards the coating unit (3); d. at least one sensing unit (7) for performing a spatially resolved optical or spectroscopic measurement method and measuring at least one second analysis parameter related to the lubricant distribution, wherein the sensing unit (7) is arranged above and / or below the substrate; e. A data processing unit (9), which is configured as follows: i. calculating at least one quality parameter, ii. comparing the at least one quality parameter with at least one first default parameter, and iii. making an affirmative determination or a negative determination as a result of the comparison; f. A control unit (8), which is constructed as follows i. in the case of a negative decision, automatically checking and / or changing at least one setting parameter by the data processing unit (9), and ii. in case of a positive determination, traversing a control loop and / or releasing the substrate for further processing, And therefore, the data processing unit (9) is configured to calculate the at least one quality parameter based on the at least one first analysis parameter and the at least one second analysis parameter, Therein, the control unit (8) is designed to detect system errors of the machine during the automatic inspection of the machine.

17. The device according to claim 16, characterized in that The substrate is a metal plate (2).

18. The device according to claim 16, characterized in that The device is designed for use in a method according to any one of claims 1 to 15 .

19. A method for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate, wherein: The machine (1) comprises at least one coating unit (3), at least one pump unit (5) connected to the at least one coating unit (3) via at least one conveying line (4), at least one sensing unit (7) for performing a spatially resolved optical or spectroscopic measurement method, and a data processing unit (9), the method comprising the following steps: a. using the at least one pump unit (5): conveying the lubricant (10) via the at least one delivery line (4) in the direction of the at least one coating unit (3); b. measuring at least one first analysis parameter by means of at least one measuring unit (6) assigned to the at least one pump unit (5), or determining the at least one first analysis parameter as a function of a machine parameter, wherein the at least one measuring unit (6) is arranged directly at the at least one pump unit (5) or alternatively in the region of the at least one conveying line (4), and wherein the first analysis parameter characterizes the flow of the lubricant towards the coating unit (3); c. using the at least one coating unit (3): applying the lubricant (10) to at least one side of the substrate; d. measuring at least one second analysis parameter related to the lubricant distribution using the sensing unit (7), wherein the sensing unit (7) is arranged above and / or below the substrate; e. using the data processing unit (9): calculating at least one quality parameter; f. using the data processing unit (9): comparing the at least one quality parameter with at least one first default parameter, wherein, as a result of the comparison, a positive or negative determination is made; g. in the case of a negative determination: automatically checking and / or changing at least one setting parameter via a control unit (8) included in the machine (1); and in the case of a positive determination: executing a control loop and / or releasing the substrate, wherein, in step e, the at least one quality parameter is calculated based on the at least one first analysis parameter and the at least one second analysis parameter, wherein, during the automatic checking in step g, a system error of the machine is detectable, Wherein, in step g, areas of the substrate where the amount of lubricant applied is insufficient are marked.

20. The method according to claim 19, characterized in that The substrate is a metal plate (2).

21. A device for automatically controlling a machine (1) for applying a lubricant to one or both sides of a substrate, wherein: The machine (1) comprises: a. at least one coating unit (3) for coating the lubricant (10) on at least one side of the substrate; b. at least one pump unit (5) connected to the at least one coating unit (3) via at least one conveying line (4), for conveying the lubricant (10) in the direction of the at least one coating unit (3) via the at least one conveying line (4); c. at least one measuring unit (6) assigned to the pump unit (5) for measuring at least one first analysis parameter, or a unit for determining the at least one first analysis parameter as a function of a machine parameter, wherein the at least one measuring unit (6) is arranged directly at the at least one pump unit (5) or alternatively in the region of the at least one conveying line (4), and wherein the first analysis parameter characterizes the flow of the lubricant towards the coating unit (3); d. at least one sensing unit (7) for performing a spatially resolved optical or spectroscopic measurement method and measuring at least one second analysis parameter related to the lubricant distribution, wherein the sensing unit (7) is arranged above and / or below the substrate; e. A data processing unit (9), which is configured as follows: i. calculating at least one quality parameter, ii. comparing the at least one quality parameter with at least one first default parameter, and iii. making an affirmative determination or a negative determination as a result of the comparison; f. A control unit (8), which is constructed as follows i. in the case of a negative decision, automatically checking and / or changing at least one setting parameter by the data processing unit (9), and ii. in case of a positive determination, traversing a control loop and / or releasing the substrate for further processing, And therefore, the data processing unit (9) is configured to calculate the at least one quality parameter based on the at least one first analysis parameter and the at least one second analysis parameter, The control unit (8) is configured to detect system errors of the machine during the automatic inspection of the machine. And wherein the regulating unit (8) is configured to mark areas of the substrate where an insufficient amount of lubricant is applied.

22. The device according to claim 21, characterized in that The substrate is a metal plate (2).

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