WEIGHING SYSTEM, MANUFACTURING DEVICE AND METHOD FOR OPERATING A MANUFACTURING DEVICE FOR WORKPIECES

Description

[0001] The present invention relates to a weighing system for workpieces according to the preamble of claim 1, a manufacturing device according to the preamble of claim 12 and methods for operating a manufacturing device according to the preamble of claim 17.

[0002] In the prior art, methods and systems for producing workpieces and products from fiber material or with portions of fiber material from a pulp are known.

[0003] For example, WO 2021 / 73674 A2 discloses such a manufacturing device with a preforming station for forming, a preforming station for preforming, and a hot forming station for final forming of a workpiece made of environmentally friendly degradable fiber material in a fiber forming process.

[0004] WO 2021 / 073672 A1 discloses an improved manufacturing device and a manufacturing process, in which a functional layer or a layer system comprising several functional layers and / or a further layer of fiber material is additionally applied to a surface of the molded part to be coated.

[0005] With these fundamentally very suitable manufacturing devices and processes, it has been shown that it is sometimes very complex to ensure a defined quality of the products and workpieces, especially at high outputs.

[0006] It is the object of the present invention to propose a manufacturing device and manufacturing method which are improved with regard to the adjustability of the quality of the workpieces and products.

[0007] This object is achieved according to the invention by a weighing system according to the features of claim 1, a manufacturing device according to the features of claim 12 and a method according to the features of claim 17.

[0008] Advantageous embodiments are specified in the respective subclaims. Further relevant prior art is disclosed in EP 2 171 394 A1.

[0009] According to this, the object is achieved by a weighing system for a product manufacturing device, comprising at least one electronically evaluable scale, comprising at least one support element for positioning at least one workpiece or workpiece stack, in particular a group of horizontally adjacent workpieces and / or workpiece stacks, and an evaluation unit connected to the scale for receiving and evaluating recorded weighing data. The scale, in cooperation with the evaluation unit, is designed to detect the total weight and the horizontal weight distribution of at least one workpiece or workpiece stack placed on the support element.

[0010] The evaluation unit can advantageously be an evaluation unit integrated into the scale and, if necessary, comprise data storage and / or be connected to at least one data storage device. Furthermore, the evaluation unit can be connected to a control unit for the manufacturing device or represent an integral part of the control device of the manufacturing device. Furthermore, the evaluation unit can comprise conventional (micro)electronic components required for operation and for measured value conversion and / or processing, such as analog-to-digital converters, processor units, interface units to adjacent local or mobile receiving units and / or communication networks, in particular to a control unit.

[0011] In this case, the support element can be designed, in particular, as a plate or shell. In one embodiment, the support element can have a support structure, frame, or the like that accommodates the support element and / or be connected thereto.

[0012] Furthermore, the term "workpiece" is not to be understood in a restrictive sense and means any preliminary or final stage of a product manufactured by means of the manufacturing device in a single- or multi-stage forming process, so that in the present case, a product is a workpiece in its final production stage.

[0013] In an advantageous embodiment, it can be provided that the carrier element 202 is formed from two or more individual carrier elements.

[0014] Although the term "one workpiece" is often used for simplification purposes, this should always be understood to refer to a group of two or more workpieces, unless otherwise stated. It is generally advantageous if, during all treatment steps, a plurality of workpieces are formed simultaneously, acted upon, and / or detected by sensors.

[0015] An advantage for the weighing system can be that the scale, in cooperation with the evaluation unit, is designed to record the respective individual weight of at least two adjacent workpieces and / or workpiece stacks as a weight distribution.

[0016] The weight distribution and the individual weights are recorded by determining the actual center of gravity and / or the vector of the actual center of gravity shift to a theoretical target center of gravity or target vector of a theoretical, expected center of gravity shift.

[0017] Advantageously, in one embodiment, it can be provided that the scale has one or two support columns which directly or indirectly support the support element for storage, which have at least one torsion sensor and / or are connected thereto, in particular have two or more torsion sensors, for at least partially determining the weight distribution.

[0018] The support columns are advantageously rigidly connected to the support element, so that a shift in the center of gravity on the support element leads to the introduction of a measurable bending moment on the support column and / or in the support element, whereby the corresponding bending moments are detected by means of suitable sensors.

[0019] If more than two support columns are provided, they are advantageously aligned in a lane or a row so that a measurable bending moment can develop in most of the partial surfaces of the support element.

[0020] In a further improved embodiment, it can be provided that the scale has at least three support elements for the carrier element, wherein the support elements have or represent force measuring sensors, wherein the at least three support elements are connected to the carrier element in a contact pattern with three contact points that are not in a row, and wherein the at least three support elements and / or their force measuring sensors are designed to send measured values ​​to the evaluation unit, which determines the total weight and the weight distribution based thereon.

[0021] The contact pattern is formed by the contact points of the support elements with the supporting element and the area enclosed thereby. In the simplest case, this is a non-rigid connection, a triangle, or a quadrilateral, whereby the polygonal designation is not to be understood as restrictive in the mathematical sense. A "corner" of this contact pattern, for example, is equivalent to the contact surface of a support element.

[0022] In a further improved embodiment, it can be provided that the weighing system and / or the evaluation unit comprises at least one input interface for receiving sensor data and / or production data, wherein the sensor data, in particular recorded geometric measured values, and the production data, in particular defined target values of at least one workpiece or at least one workpiece stack.

[0023] Therefore, the weighing system ideally includes a sensor unit.

[0024] Advantageously, the A sensor that detects the geometry of the workpiece is a sensor that detects a two-dimensional shadow area of ​​the workpiece and / or the workpiece stack, such as a CCD camera, a line scan camera, etc., or that detects a topography of the workpiece and / or the workpiece stack, such as a 3D laser scanner. Furthermore, it may be advantageous to provide at least one sensor that detects a target value of the workpiece and detects at least one other material value, such as a heat sensor, a humidity sensor, a radiation and / or a light sensor, etc.

[0025] In order to be able to derive conclusions from the weighing data for the manufacturing process and the manufacturing device, it is advantageous to evaluate the weighing data. This can be achieved, as described above, by using a sensor unit that records different values ​​of the workpiece mass. Because the masses determined from the weighing data of the scale are of central importance for the evaluation of the workpieces and the control of the manufacturing process and method, a further improved embodiment of the weighing system can be provided that includes an additional scale connected to the evaluation unit. In particular, this should be an additional scale that, in addition to the first scale, has the following: a different arrangement of the at least one support column or a different contact pattern of the support elements or, instead of the at least one support column of the first scale, at least three support elements in a contact pattern.

[0026] In this case, the connections to one or the same evaluation unit and / or other elements, in particular a sensor unit as described above, are to be provided in an analogous manner. In other words, it may be advantageous if the second scale differs from the first scale in terms of scale type and / or design with regard to the contact pattern of the contact points and / or the arrangement of the support columns.

[0027] Thus, a different contact pattern can be used to achieve a different resolution of the position of the actual center of gravity and thus to verify the real actual center of gravity and / or the load distribution on the individual support columns or support elements.

[0028] A further improvement of the weighing system can be that in a further embodiment it is provided that the at least one scale is integrated into a conveyor unit, wherein the conveyor unit ▪ comprises a conveyor belt as a conveying means, wherein the scale is integrated into the conveyor belt in such a way that the carrier element is covered by at least one belt layer and / or ▪ comprises a conveying means by means of which the scale can be transported at least partially, in particular a transport robot or a linear drive, in particular an electromagnetic linear drive.

[0029] If the scale is integrated into a conveyor unit, it can be advantageous if at least one support element is covered or draped over by only one layer of belt. Especially with very light workpieces whose weight is significantly less than the weight of the support element, it has been found that the influence of the belt position has a strong impact on the weighing data, with this influence decreasing as the weight of the workpieces or workpiece stack increases. Therefore, it can be advantageous if the belt tension and belt drive are controllable, so that the belt of the conveyor unit can be relaxed during the weighing step and / or stopped briefly while the weighing is taking place.

[0030] In an alternative embodiment, it may be advantageous for the support element to be a support structure attached to the frame of a weighing conveyor belt belonging to the scale. This weighing conveyor belt is ideally integrated into the conveyor unit. In this embodiment, the weighing conveyor belt and the support structure are recorded as the tare weight. Furthermore, in this embodiment, it is advisable to apply very high tension to the belt of the weighing conveyor belt and / or to provide a very inflexible belt material in order to minimize the deformation in the belt material that cannot be measured by the scale.

[0031] In a further advantageous embodiment, it can be provided that the scale comprises at least two drivable support elements in the form of rollers, in particular rollers equipped with or forming a tubular motor. In this case, the rollers are arranged at least on one side on at least one support element, so that the weight and / or the weight progression of the workpieces can be recorded when resting on a roller, in particular when traveling over it. This embodiment can be improved by having a plurality of drivable rollers form the support element, each of which is arranged on both sides of a support element. The support elements are connected to the evaluation unit, which is equipped to determine the weight of an individual workpiece and / or the actual center of gravity of at least one workpiece and / or at least one stack of workpieces from the individual weighing data of the evaluation units.

[0032] The evaluation unit is particularly equipped to determine the weight of a horizontally arranged group of workpieces and / or workpiece stacks and the actual center of gravity from the individual weighing data of the evaluation units.

[0033] In a further improved embodiment, it can be provided that the at least one scale is designed as a dynamic scale and comprises corresponding components in order to carry out a dynamic measurement, wherein the workpieces are conveyed relative to the scale during the measurement and / or is designed as a static scale and comprises corresponding components in order to carry out a static measurement, wherein the workpieces are stationary relative to the scale during the measurement and are not conveyed in order to carry out a static measurement.

[0034] In other words, dynamic weighing is understood to mean a weighing step in which the workpieces are moved simultaneously and, in particular, exhibit a speed relative to the scale, the support elements, and / or the support columns. Similarly, static weighing is understood to mean a weighing step in which the workpieces are at rest simultaneously and, in particular, exhibit no relative speed relative to the scale, the support elements, and / or the support columns. Thus, a weighing step in which the workpieces are transported parallel to the scale constitutes a special form of static weighing.

[0035] In a further improved embodiment, it can be provided that at least one support element is mounted displaceably relative to the carrier element, advantageously drivable, in particular motor-driven, and / or the carrier element is mounted displaceably relative to at least one support element, advantageously drivable, in particular motor-driven.

[0036] By changing the position of the support elements relative to the carrier element, the target center of gravity is changed in a defined manner, allowing an initial measurement tailored to the workpieces or workpiece stack and / or a subsequent, controlling measurement step to be performed. Especially with very light workpieces and / or when depositing the first group or layer of workpieces that will subsequently be covered to form a stack, it can be advantageous to redundantly monitor the center of gravity position and / or weight distribution early on. This can be done alone or in conjunction with other measured values.

[0037] In this case, it may be advantageous if a linear guide is arranged between the carrier element and the free end of the support element, in which the free end of the support element can be guided. In particular, it may be advantageous if the carrier element has at least one linear guide on its side facing the support elements, in which the free end of at least one support element is displaceably mounted. The linear guide is not to be understood as restrictive and can be a path of any shape, in particular with at least one straight and / or curved path section.

[0038] In a further improved embodiment, it can be provided that the at least one scale is arranged on or at an electromagnetic direct drive with at least one drive rail and at least two movers that can be driven and controlled independently of one another and / or is formed thereby.

[0039] The drive rail of the direct drive is specifically designed as a drive oval, along which the movers can rotate continuously. Ideally, the drive oval has a straight, short-free measuring section (back section), two deflections, and a return section (return section). The measuring section is defined in particular by the fact that the weighing step can be performed there, regardless of the conveying speed and conveying direction during the measuring step.

[0040] In a further improvement of this embodiment, it can be provided that at least one first mover or a first drive unit has at least one support element and at least one further mover or a further drive unit has at least one further support element.

[0041] It is particularly advantageous if two pairs of movers are provided, i.e., a total of four movers, each with a support element that can be driven from one another, form the balance, which supports the support element in a defined manner. If the support element has a linear guide on at least one side of the underside, the relative position of the support elements can be changed, and thus the desired center of gravity can be changed in a defined manner. In other words, by moving the support elements closer together or further apart from one another, a change in the desired center of gravity and thus the resolution of the actual center of gravity relative to the desired center of gravity can be initiated.

[0042] In a further improved embodiment, it can be provided that at least one support element can be deactivated and / or removed vertically from the respective contact point.

[0043] In this case, contactless means that the contact between the support element and the carrier element is released and the two elements are separated for at least a short time. This also allows for a variation of the target center of gravity, thus verifying the actual center of gravity, even with more than three support elements.

[0044] Although the primary focus here is on determining a "center of gravity," this is intended to be synonymous with "determining the weight shares" of individual support columns and / or individual support elements, because the "center of gravity" (target center of gravity and / or actual center of gravity) is derived from this. The target center of gravity can, in particular, be a theoretically defined data set or value that can be expected under ideal conditions.

[0045] The invention further comprises a manufacturing device for workpieces comprising a material feed unit, a forming unit and a discharge unit, wherein the forming unit has at least one forming station with at least one forming tool and at least one pressing device, wherein the at least one forming tool is held on the pressing device and can be moved by a motor drive thereof and wherein at least one control unit is provided by means of which at least one unit and / or one device can be controlled and / or regulated. In this case, a weighing system for determining weighing data of at least one workpiece and / or at least one stack of workpieces according to one of the preceding embodiments and variants is advantageously included, wherein the weighing system is arranged in particular in the forming unit and / or downstream of the forming unit.

[0046] The production device can further comprise a material feed unit for starting materials such as a fibrous pulp or other consumables. This material feed unit is advantageously connected to a supply unit and / or a feed unit. Advantageously, the pressing device has support and fastening elements for at least one molding tool, which can in particular be a heated molding tool.

[0047] Here, "aggregate" means any controllable and adjustable component and "device" means any actuator and / or sensor, whereby a "device" can also be an "aggregate".

[0048] The manufacturing device is designed and has corresponding means for releasing workpieces from a molded part, in particular by means of compressed air. A particular advantage is that the molding tool and / or a device holding and / or driving the molding tool is designed to position a workpiece or a group of workpieces from the molding tool directly onto the scale, in particular onto the support element.

[0049] In an improved embodiment of the manufacturing device, it can be provided that the at least one forming station and / or its at least one forming tool is designed for the pressing forming of workpieces from a starting material and / or is designed for the pressing and hot forming of workpieces from a starting material and / or a preform of a workpiece, in particular comprising two forming stations, each with at least one forming tool.

[0050] Furthermore, a preforming station can be provided upstream of the first forming station. This preforming station comprises a movement unit, such as an articulated-arm robot, with a suction tool. The suction tool is designed and movable so that the provided free-flowing or flowable starting material can be sucked in and a preform of the workpiece can be formed. This preform, which usually has a very high moisture content, is then further formed in a forming station.

[0051] Furthermore, it may be advantageous if a finishing unit for the workpieces and / or workpiece stacks is provided downstream of the forming station, in particular downstream of the second forming station, which is advantageously designed as a hot-forming station. The finishing unit may comprise a cutting station, a coating station, a stacking station, and / or a packaging station. In the cutting station, the workpieces are finished by removing material, and in the coating station, a gas- and / or liquid-barrier layer is applied, in particular to the inside of the workpieces, to at least one partial surface.

[0052] In a further improved embodiment, it can be provided that the weighing system comprises a scale which is arranged downstream of the at least one forming tool for the pressing forming of workpieces and in particular is arranged downstream of the forming tool for the pressing and hot forming of workpieces.

[0053] Here, "downstream" also means that the scale can be integrated into the mold and can carry out the weighing step in the associated mold after forming.

[0054] In a further improved embodiment, it can be provided that the evaluation unit and the control unit are connected in such a data-conducting manner and are functionally designed, in particular using corresponding software programs, so that the control unit can control and / or regulate at least one unit and / or one device at least in two ways based on the weighing data received from the evaluation unit, in particular evaluated weighing data (evaluation data), in particular at least one unit and / or one device upstream of the scale can be controlled and / or regulated at least in two ways.

[0055] In this context, "evaluation data" refers to any data that the evaluation unit forwards and / or stores after evaluation. Evaluation data can, in particular, consist of a selection of weighing data, parameters, or characteristic curves for controlling units or actuators, particularly units and actuators located upstream of the scale. Furthermore, evaluation data can also include data relating to supplementary and / or modified recording using sensors, for example, to verify weighing data and / or other measurement data.

[0056] The evaluation data can be determined and processed in particular using AI-based software (artificial intelligence), in particular by jointly considering other measured values ​​and measurement data.

[0057] Evaluation data may also include data that may represent a warning or signal indication on a human-machine interface (HMI) and / or be emitted by another signaling device, such as a lamp, an LED display and / or a sound emitter.

[0058] In a further improved embodiment, it can be provided that at least one forming station and / or at least one forming tool is designed to form a group of two or more workpieces and comprises and / or is designed to release and / or hold individual workpieces and / or groups of workpieces in a controlled manner, in particular to release them directly onto the scale and / or the support element of the scale.

[0059] As a release mechanism, the suction tool and / or the forming tool can, for example, have internal channels or chambers that can be controlled individually or as a subgroup and subjected to a vacuum and / or a pressure pulse. In this way, workpieces can be ejected and deposited at staggered times. The suction tool and / or the forming tool and the associated internal channels and chambers are designed and controllable in such a way that workpieces can be released in rows, columns, or subgroups.

[0060] Advantageously, the workpieces of a row, column or subgroup are then weighed one after the other until the entire group that a tool can hold is completely deposited and weighed.

[0061] Furthermore, the invention comprises a method for operating a manufacturing device, comprising the steps: Providing a starting material, introducing a starting material into a forming unit, wherein the forming unit has at least one forming station with at least one forming tool and at least one pressing device, ideally two pressing devices, and forming at least one workpiece, in particular a group of workpieces, by means of the forming tool.

[0062] In this case, downstream of the forming station, the total weight and the horizontal weight distribution of at least one workpiece or stack of workpieces positioned on the carrier element are recorded in a weighing step by means of a scale of a weighing system; in particular, a group of two or more positioned workpieces or stacks of workpieces is recorded.

[0063] The starting material is supplied as a flowable or pourable material and is made available, for example, in an open storage container for a suction tool for preforming.

[0064] In an improved embodiment, the workpiece is positioned directly on the scale by the forming tool and / or the pressing device. The ejection of a workpiece from a tool can be achieved in any suitable manner, in particular via at least one gas pressure pulse, i.e. by blowing out the workpieces. In an improved version of the method, the workpieces of a group are not all ejected simultaneously, but rather as rows, columns, or subgroups. For this purpose, for example, a pressure pulse can be exerted on only a number of the workpieces and / or another subgroup that is not yet to be ejected can be held in the tool by introducing a vacuum.

[0065] In an improved method variant, it can be provided that after the joint forming of a group of two or more workpieces, a step-by-step weighing is carried out for a number (subgroup) of workpiece layers greater than or equal to 2, in particular a layer-by-layer weighing of the workpieces is carried out.

[0066] A further advantage can be achieved if the group of workpieces that a tool can hold simultaneously is ejected in only one row or column of workpieces, stacked one after the other, and weighed after each ejection. In other words, from each group of workpieces from n rows and m columns that a tool can hold simultaneously, only a single row with n layers or only a single column with m layers formed.

[0067] In the present case, a "row" is understood to mean a subgroup or row of adjacent workpieces or positions for workpieces that are aligned transversely to the main transport direction and, analogously, a "column" is understood to mean a subgroup or row of workpieces or positions of workpieces that are aligned parallel to the main transport direction.

[0068] The great advantage is that it is possible to differentiate the individual workpiece positions of a tool in a very simple way if a positioned subgroup of workpieces has a different weight or weight distribution than other subgroups.

[0069] It will be understood by those skilled in the art that these process variants can be carried out not only row-by-row or column-by-column, but also combinations are conceivable. If a total stack to be formed on the scale consists of n rows, m columns, and k layers, a partial stack consisting of n rows, m columns, and k-3 layers could be formed row-by-row in the first weighing steps. Subsequently, the last three layers of the total stack could be positioned one after the other, column-by-column, and weighed individually.

[0070] This process variant can also be carried out in an analogous manner for subgroups of workpieces that are not ejected in rows or columns and positioned on the support element of the scale.

[0071] A further improvement of the method can be that after the joint forming of a group of two or more workpieces, a multiple weighing is carried out before the next forming of a next group of workpieces by independently weighing a partial number of workpieces of the jointly formed group in partial weighings.

[0072] A method analogous to step-by-step weighing can be used here, in particular the ejection of subgroups of workpieces from a forming tool and positioning them on the carrier element.

[0073] A further improvement of the process may be that the weighing step takes place after the first forming and a further forming.

[0074] Thus, at least one scale is arranged between a preforming station and a first forming station and / or a first forming station and a downstream second forming station for workpieces.

[0075] A further improvement of the method can be that in the weighing step, weighing data are determined and sent to an evaluation unit, wherein the evaluation unit sends the weighing data, in particular the evaluation data, to a control unit and based thereon at least an aggregate and / or a device is controlled and / or regulated at least temporarily and / or an information and / or warning signal is sent to an output unit, in particular a HMI, an optical or acoustic signal device.

[0076] "Based" here means that these weighing data or evaluation data are used solely or in addition to the control, which can occur immediately or with a time delay. Control is also carried out with the integration of target value specifications, especially algorithms, value tables, and / or AI.

[0077] Overall, it may be advantageous if the weighing system is designed according to one of the aforementioned embodiments and variants. It may also be advantageous if methods are used for a manufacturing device that are designed according to one of the aforementioned embodiments and variants.

[0078] All advantages, aspects and features as well as combinations of features mentioned above for one category, such as the weighing system, the manufacturing device or the (manufacturing) process, shall apply analogously to the other category(ies), unless technically impossible.

[0079] Furthermore, no distinction should be made here between measured values ​​and measured data and, unless otherwise stated, these terms should be used synonymously, since the person skilled in the art knows how processed measured data, in particular digital measured data, can be derived from the raw and possibly analogue measured values, for example from a sensor and, furthermore, the type and extent of the measured values ​​and measured data transmitted by a sensor depends on the design and range of functions of a sensor.

[0080] Further details and advantages of the invention will now be explained in more detail with reference to an embodiment shown in the drawings.

[0081] They show: Fig. 1 is a schematic view of a manufacturing device with the weighing system, Fig. 2 is the weighing system in a first embodiment, Fig. 3 is the weighing system in a second embodiment, Fig. 4 is the weighing system in a third embodiment, Fig. 5 is the weighing system in a fourth embodiment, Fig. 7 is the weighing system in a fifth embodiment and Fig. 8 is the weighing system in a sixth embodiment.

[0082] The Figure 1 shows, by way of example, a schematic structure of a manufacturing device 500 for producing workpieces 150 from a fiber material. Here, the weighing system 100 is shown in context and in a possible installation position in a manufacturing device 500 after a second forming station 508.

[0083] The manufacturing device 500 comprises a material feed unit 502, a preforming station 518, a first forming station 506, a second forming station 508, a finishing unit 522, and a discharge unit 512. A feed tank 520 is included as part of the preforming station 518. The first forming station 506 comprises a movement unit 524, designed as a multi-axis robot, on which a suction tool 510 preforming the workpieces is arranged and guided. The finishing unit 522 can, if required, comprise one or more functions and corresponding stations, such as coating, cutting, stacking, and / or packaging. A discharge unit 512 is also provided.The material feed unit 502 forms a production line with the forming unit 504 and the assembly unit 522, wherein the discharge conveyor 512 connects the scale 200 of the weighing system 100, the second forming station 508 and the assembly unit 522 or is connected downstream of the assembly unit 522 for the discharge of the workpieces in the respective batch sizes and / or packaging units.

[0084] The scale 200 of the weighing system 100 is part of a conveyor unit 160 and structurally integrated into the conveyor 162, which in the illustrated embodiment is designed as an endlessly circulating conveyor belt 164. The carrier element 202 rests on three support elements 210, as shown in the left-hand detail, and is covered by a belt layer 166. In the weighing step, the workpieces 150 or workpiece stacks 152 are weighed together with the portion of the belt layer 166 that rests on the carrier element 202. The assembly unit 522 or the discharge unit 512 is connected to the conveyor 162.

[0085] The scale 200 is connected to the evaluation unit 300 and the control unit 320 via data lines, which are shown by the dashed lines as data lines 304. The data lines 304 can be multi-wire. In particular, the data lines 304 can be combined data and power lines, such as in an IO-Link or SPE with DoPL (Single Pair Ethernet with Data over Powerline). The control unit 320 is connected to other units and devices, as shown by the dashed lines.

[0086] To preform workpieces 150, the suction tool 510 is lowered into the feed tank 520 filled with a pulp containing fiber material as the aqueous phase, and a defined layer of moist fiber material is sucked onto the contour of the sieve-like suction tool 510 by means of the vacuum pump 142. A pressure sensor 210 can be provided in the line between the vacuum pump 142 and the suction tool 510, via which the pressure in the suction line and thereby also the degree of contamination of the suction tool 510 can be detected, in particular in conjunction with and in correlation with the line consumption of the vacuum pump 142, which can be detected via an integrated sensor. This defined layer is then dewatered and pre-pressed in the first forming station 506. This takes place at a temperature in the range of 30°C to 80°C and a pressure in the range of 0.2 N / mm 2 to 0.3 N / mm 2 .Subsequently, after the preformed workpieces have been transferred to a hot pressing tool 134 of the second forming station 508, the final forming of the workpieces 150 takes place. This second forming station 508 is designed as a main or hot forming station.

[0087] The forming process in the second forming station 508 takes place at a (main) pressure in the range of 0.5 N / mm 2 to 2.0 N / mm 2 and a temperature of 100 °C to 250 °C. This process is generally known. In a variant of the process (not shown), the final forming of the workpieces takes place in a single hot and pressing step, which is generally very energy-intensive.

[0088] The control unit 320 controls and regulates the manufacturing device in a manner not shown in detail and, likewise in a known manner, receives and evaluates measurement and / or status data from the assemblies, actuators, sensors, and sensor units. This reception and evaluation of measurement and status data can occur in parallel with the reception and evaluation of measurement and status data from the evaluation unit 300.

[0089] As can be seen in the left-hand detailed drawing, the support element 202 of the scale 200 is arranged on three support elements 210, whose three contact points 220 form a triangular contact pattern 222 with the support element. The main transport direction is from right to left in the image plane, so that the group of workpieces forms an arrangement of 3 rows and 4 columns, which corresponds to the 12 forming elements of the associated forming tool 516. By distributing the weight among the three support elements 210 and / or the position of the actual center of gravity 238 relative to the desired center of gravity 236, the weight of an individual workpiece 150 can be estimated or specifically determined, as will be explained in more detail in the following figures.

[0090] As can also be seen in the left-hand detail, the control loop 254 consists of weighing the group of workpieces 150, possibly weighing them from a layer on top of previously weighed workpieces 150, and then performing referencing 214. Referencing 214 consists of calculating the tare and / or zeroing the already loaded support element. Subsequently, the next group of workpieces 150 is positioned and weighed until the final height of the workpiece stack 152 with the desired number of layers is reached. Subsequently, the workpieces are rejected by the reject unit 512 and / or transferred to the assembly unit 522.

[0091] In the Figure 2The scale 200 is shown schematically in a plan view of the support element 202. The support element 202 is arranged on four support elements 210, which form a rectangle as a contact pattern 222. Also positioned on the support element 202 are 12 workpieces 150, which, due to the main transport direction 252, form a group of workpieces 150 consisting of 3 rows and 4 columns.

[0092] Due to the geometry of the support element 202 as a rectangular plate and the symmetrical support of the support element 202 on the four support elements 210 and due to the ideal, symmetrical positioning of the 12 workpieces 150, the desired center of gravity 236 during a weighing step is in the center of the support element 202, i.e. at the intersection point of the diagonals of the support element and / or the connecting lines of the contact points 220, since the contact points 220 are also arranged symmetrically distributed below the support element 202.

[0093] For a better understanding, the Figure 2 and other figures, dashed auxiliary lines are drawn, such as the diagonals or the center line, although these auxiliary lines are not provided with reference symbols.

[0094] As soon as at least one workpiece 150 has a different weight than the other workpieces 150, the weight distribution on the four support elements 210 changes and thus also the resulting actual center of gravity 238, which in this case always means the actual center of gravity position. In the exemplary embodiment shown, for example, the total weight of the group of workpieces 150 has decreased and the actual center of gravity 238 has shifted downwards to the left along the diagonal. It can therefore be concluded that the workpiece 150 in the upper right corner has too little material. Since the workpieces 150 are pre-formed in discrete sections of the suction tool 510, it can be concluded with a high statistical probability that the workpiece 150 in the upper right corner is lighter by essentially this weight fraction.Furthermore, it can be concluded with a high degree of probability that there is increased contamination in this area of ​​the suction tool 510.

[0095] In an analogous manner, a multitude of estimates can be derived from the position of the actual center of gravity 238 relative to the expected target center of gravity 236, which relate to the weight of the individual workpieces 150 and also to the condition of individual tools and / or process parameters.

[0096] If, for example, the total weight of the group increases over time, i.e. the total weight of a group relative to previous groups of workpieces, it can be concluded that either the dewatering in the first forming station 506 is not of the desired quality and / or the heating line in the second forming station 508 is defective. From the gradient of the change, it can also be deduced whether the manufacturing process and thus the manufacturing device must be stopped immediately or whether continued production under possibly adapted conditions, such as an extended treatment in one or both forming stations, is sufficient until a desired batch of workpieces is completed and the manufacturing device is subjected to a routine cleaning process.

[0097] In the Figure 2further comprises a sensor unit 310 having two sensors 312, 314. This sensor unit 310 or the two sensors 312, 314 are connected to the evaluation unit 300 and / or the control unit 320 in a data-conducting manner.

[0098] In the example shown, the first sensor 312 is a 3D laser scanner, by means of which the topology of the workpiece 150 can be detected and / or the surface roughness or surface flatness can be detected. These measured values ​​provide information, in particular but not exclusively, about the mechanical influences of the previous tools. The second sensor 314 is a thermal imaging camera, whose measured values ​​provide information, in particular but not exclusively, about the area-specific heating power of the second forming station 508 and the forming tools 516 there. From these measured values, for example, when viewed together with the electrical power consumed for the heating and any characteristic curves, estimates can be derived as to whether a high degree of contamination is present in the tool 516, so that the entire amount of heat is no longer transferred to the workpiece 150.

[0099] In the Figure 3The position of the different centers of gravity on the support element 202 of the scale 100 is shown in three partial images. For illustration purposes, two workpieces 150 of very different sizes and therefore correspondingly different weights, which are made of the same starting material, are placed on top. The rectangular support element 202 has a center of gravity 230, which lies at the intersection of the diagonals and / or the intersection of the center lines of the sides. In the example shown, the contact points 220 form an arbitrary triangle as a contact pattern 222, whose center of gravity 232 lies, in a known manner, at the intersection of the lines running from the side centers to the respective opposite corners.

[0100] Thus, a resulting center of gravity 235 from the support element 202 and the triangular contact pattern 222, which lies on the connecting line of these two centers of gravity, results as a theoretical target center of gravity for an empty support element 202, as shown in the upper part of the Figure 3 is shown.

[0101] The upper and middle partial images further show that the group of the two workpieces 150 has a common center of gravity 234, which lies on the connecting line between the centers of gravity of the individual workpieces 150 and is arranged significantly closer to the left, larger workpiece 150.

[0102] Finally, the target center of gravity 236, which results after the ideal positioning of the ideally weighted workpieces 150 on the support element 202, lies on the connecting line between the resulting center of gravity 235 and the center of gravity 234 of the group of workpieces 150, as shown in the middle part of the figure.

[0103] As shown in the lower partial image, the target center of gravity 236 results from the weight proportions represented as double arrows, which are measured by the support elements 210 at the three contact points 220. The weight proportion correlates with the length of the respective double arrow. If, for example, the larger workpiece 150 has a greater mass and / or the smaller workpiece 150 has an insufficient mass, the detected actual center of gravity 238 shifts toward the larger workpiece 150, the case shown in the lower partial image. From the total weight and the position of the actual center of gravity 238, the weight of both workpieces 150 can be clearly determined for these two workpieces 150.

[0104] In the Figure 4 In the upper part of the picture there is a Figure 3An identical arrangement is shown, whereby not all centers of gravity are shown, only the center of gravity 230 of the support element 202 and the measured actual center of gravity 238, which results from the measured weight proportions of the three support elements 210. In the lower part of the image, the support element 202 has been rotated by 180° and the three support elements 210 of the scale 200 or another scale 200 have been arranged as an equilateral triangle. Thus, a review of the previous measurement can be carried out in a further measuring step, because with the known, identical total weight of the two workpieces 150 and the determined actual center of gravity 238, a second target center of gravity 236 based on the measured actual center of gravity 234 from the first measuring step is available for this second measuring step, and the changed positions of the contact points 220 lead to a different spread and thus a new distribution of the detectable weight proportions for the three support elements 210.Such a second measurement step can be used to identify, in particular, randomly occurring, opposing effects.

[0105] This could, for example, be an increase in weight for a subset of workpieces 150 with a simultaneous decrease in weight for another subset of workpieces 150, which, due to a symmetry of the support elements 210 and the symmetry of the group of workpieces 150, leads to no or only an insignificant shift of the actual center of gravity 238. This case is also not unlikely because, for example, the closure in sub-areas of the suction tool 510 during the accumulation of starting material leads to an increased suction of starting material in other sub-areas of the suction tool 510 if the sub-areas are pneumatically connected via a common interior space or internal channels.

[0106] In the Figure 5An embodiment is shown in which the scale 200 is carried and driven by a linear drive 180 or the scale 200 is also formed by components of the linear drive 180 or is completed thereby. The linear drive has four individual movers 184, which are guided and driven on parallel drive rails 182. The movers 184 are simultaneously the support elements 210 of the scale 210 or carry the support elements 210, wherein the contact points 220 with the support element 202 are provided in an analogous manner, as described above. The support element 202 is designed as a conveyor panel. The support element 202 is analogous to Figure 3 or 4supported by three support elements 210, via which the weight components are measured, which together form a triangular contact pattern 222. Two of the movers 184 have a single support element 210, and a pair of movers 184 are rigidly connected via a support element 186, in the center of which the third support element 210 is arranged. The scale 200 is thus designed and usable as a static scale 200, wherein in the weighing step the workpieces 150 are not moved and the workpieces are moved 150 and / or at least temporarily, wherein the workpieces 150 have no relative speed to the scale 200.

[0107] The movers 184 can be driven in various ways, whereby in an advantageous embodiment, which is provided here as an alternative, the linear drive 180 is an electromagnetic linear drive 180, which is formed, for example, as a vertically formed, oval section on two parallel sections. The movers 184 are independently controllable. In the illustrated embodiment of the two partial images of the Figure 5 the support element 210 shown top left is in a fixed position below the carrier element 202. The right, middle support element 210 and the lower, central support element 210 are both mounted and guided in parallel guide curves 188, which are also arranged below the carrier element 202, so that the relative position of the support elements 210 to one another can be changed.

[0108] In the embodiment of the Figure 6The scale 200 of the weighing system 100 is included, which is connected to a unit that includes the control unit 320 and the evaluation unit 300. Furthermore, the transport element 202 of the scale 200 is formed from a plurality of transport rails 203 that are mounted on a common support element (not shown). In the example shown, the support element rests on four support elements 210. Between and to the side of the support rails 203 of the transport element 202 are arranged five narrow conveyor belts 526, which can be driven individually or jointly. If workpieces 150 are ejected from the forming unit 504 and positioned on the scale 200 or a preceding transport means and transferred to the transport element 202 of the scale 200, weighing can take place in the weighing step, as described above.In an alternative embodiment, the transport rails 203 or the entire transport element 202 are mounted so as to be movable in the vertical direction and / or the individual or the entire group of narrow conveyor belts 526 are mounted so as to be movable in the vertical direction, so that the workpieces 150 can be brought out of contact with the narrow conveyor belts 526. In this way, the influence of a conveyor belt during the weighing step can be prevented.

[0109] The group of narrow conveyor belts 526 may be part of the rejection unit 512, part of the scale 200 and / or part of another adjacent unit, such as the forming unit 504 or the packaging unit 522.

[0110] In the embodiment of the Figure 7the scale 200 is designed as a conveyor unit 160 or integrated into a conveyor unit 160, in that the support element 202 is formed from a plate-like carrier 167, which has lateral holding sections 165, to which a conveyor belt 164 with two deflection rollers 168, which can be driven endlessly by means of a motor 169, is suspended. In the weighing step, the workpieces 150 standing or being transported on the belt are weighed together with the support element 202 and the conveyor belt 164, as explained herein. In an alternative embodiment, the carrier can, for example, be analogous to Figure 2 have displaceably mounted support elements 210 or be connected thereto. Furthermore, the scale 200 is connected in an analogous manner to a control unit 320 and / or an evaluation unit 300.

[0111] Figure 8shows an embodiment in two partial images, in which the support elements 202 of the scale 200 are arranged between the rear run (upper run) and return run (lower run) of a conveyor belt 164. The upper partial image shows a vertical section and the lower partial image a bottom view of the support element 202 and the support element 210 there. In this embodiment, the upper belt layer 166 (upper run) rests on the support element 202 and is weighed in the weighing step together with the respective workpieces 150, wherein it can be provided that at least one deflection roller 168 is movably mounted for belt relaxation.

[0112] Here, the scale 200 and the conveyor belt 164 can be attached to a common support structure or the scale 200 is attached to its own support structure 218, as in the example shown. List of reference symbols

[0113] 100Weighing system 140Starting material 142Vacuum pump 150Workpiece, product 152Workpiece stack, product stack 154Support surface 160 Conveyor unit 162 Conveying means 164 Conveyor belt 165 Holding section 166 Belt layer 167 Carrier 168 Deflection roller 169 Motor 180Linear drive 182Drive rail 184Mover 186Support element 188Guide curves 200Scale 202Support element 203Support rail 210Support element 216Referencing 218Supporting structure 220Contact Point 222Contact Pattern 230Focus of 202 232Focus of 228 234Center of gravity of 150 235Center of gravity, resulting 236Target center of gravity 238Actual center of gravity 252Main transport direction 254Control loop 300Evaluation unit 302Input interface 304Data line 310Sensor unit 312Sensor, 3D laser scanner 314Sensor, thermal imaging camera 320Control unit 500 Manufacturing device 502 Material feed unit 504 Forming unit 506 First forming station 508 Second forming station 510 Suction tool 512 Rejection unit 516 Forming tool 518 Preforming station 520 Feed tank 522 Finishing unit 524 Movement unit 526 Conveyor belt

Claims

1. A weighing system (100) for a manufacturing device (500) for products, comprising at least one electronically evaluable scale (200) comprising at least one carrier element (202) for positioning at least one workpiece (150) or workpiece stack (152), in particular a group of horizontally adjacent workpieces (150) and / or workpiece stacks (152), and an evaluation unit (300) connected to the scale (200) for receiving and evaluating recorded weighing data, characterized in that the scale (200) is designed to detect, in cooperation with the evaluation unit (300), the total weight and the horizontal weight distribution of at least one workpiece (150) or workpiece stack (152) placed on the carrier element (202), the scale (200) being designed to quantify and differentiate, in cooperation with the evaluation unit (300), the respective individual weight of at least two adjacent workpieces (150) and / or workpiece stacks (152) as a weight distribution.

2. The weighing system (100) according to claim 1, characterized in that the scale (200) has one or two support columns which directly or indirectly support the support element (202) for placement, each of which has at least one torsion sensor, in particular two or more torsion sensors, for determining the weight distribution at least partially.

3. The weighing system (100) according to any one of the preceding claims, characterized in that the scale (200) has at least three support elements (210) for the carrier element (202), wherein the support elements (210) have or constitute force-measuring sensors, wherein the at least three support elements (210) are connected to the carrier element (202) in a contact pattern (222) with three contact points (220) that are not in a row, and wherein the at least three support elements (210) and / or the force-measuring sensors thereof are designed to send measured values to the evaluation unit (300) which determine, based thereon, the total weight and the weight distribution.

4. The weighing system (100) according to any one of the preceding claims, characterized in that the evaluation unit (300) comprises at least one input interface for receiving sensor data and / or production data, wherein - the sensor data relate, in particular, to recorded geometric measured values and - the production data relate, in particular, to defined target values of the at least one workpiece (150) or of the at least one workpiece stack (152).

5. The weighing system (100) according to any one of the preceding claims, characterized in that an additional scale is included which is connected to the evaluation unit (300), the additional scale having, relative to the first scale (200), - a different arrangement of the at least one support column or a different contact pattern (222) of the support elements (210) or, - instead of the at least one support column, at least three support elements (210) in a contact pattern (222).

6. The weighing system (100) according to any one of the preceding claims, characterized in that the at least one scale (200) is integrated into a conveyor unit (160), wherein the conveyor unit (160) comprises - a conveyor belt (164) as a conveying means (162), the scale (200) being integrated into the conveyor belt (164) such that the carrier element (202) is covered by at least one belt layer (166) and / or - a conveying means (162) by means of which the scale (200) can be transported at least partially, in particular a transport robot or a linear drive (180), in particular an electromagnetic linear drive (180).

7. The weighing system (100) according to any one of the preceding claims, characterized in that the at least one scale (200) is embodied - as a dynamic scale and comprises corresponding components for carrying out a dynamic measurement, the workpieces being conveyed relative to the scale (200) during the measurement and / or - as a static scale and comprises corresponding components for carrying out a static measurement, the workpieces being positioned relative to the scale (200) during the measurement and not being conveyed in order to carry out a static measurement.

8. The weighing system (100) according to any one of the preceding claims, characterized in that - at least one support element (210) is displaceably mounted and drivable relative to the carrier element (202) and / or - the carrier element (202) is displaceably mounted and drivable relative to at least one support element (210).

9. The weighing system (100) according to any one of the preceding claims, characterized in that the at least one scale (200) is arranged on or at an electromagnetic direct drive (180) with at least one drive track (182) and at least two independently drivable and controllable movers (184) and / or is formed by the same.

10. The weighing system (100) according to claim 9, characterized in that - at least one first mover (184) or one first drive unit (186) has at least one support element (210), and - at least one additional mover (184) or one additional drive unit (186) has at least one additional support element (210).

11. The weighing system (100) according to any one of preceding claims 3 to 10, characterized in that at least one support element (210) can be deactivated and / or removed vertically from the respective contact point (220).

12. A manufacturing device (500) for workpieces (150), comprising a material feed unit (502), a forming unit (504), and a discharge unit (512), wherein the forming unit (504) has at least one forming station (506) with at least one forming tool (508) and at least one pressing device (510), wherein the at least one forming tool (508) is held on the pressing device (510) and is movable by means of a motor drive, and wherein at least one control unit (320) is provided by means of which at least one unit and / or one device can be controlled and / or regulated, characterized in that a weighing system (100) for determining weighing data of at least one workpiece (150) and / or of at least one workpiece stack (152) according to any one of the preceding claims is included, the weighing system being arranged particularly in the forming unit (504) and / or downstream from the forming unit (504).

13. The manufacturing device according to claim 12, characterized in that the at least one forming station (506) and / or the at least one forming tool (508, 510) thereof is designed - for the pressing-type formation of workpieces (150) from a starting material (140) and / or - for the pressing and hot forming of workpieces (150) from a starting material (140) and / or from a preform of a workpiece (150), in particular comprising two forming stations (506), each with at least one forming tool (508, 510).

14. The manufacturing device according to any one of claims 12 or 13, characterized in that the weighing system (100) comprises a scale (200) which is arranged downstream from the at least one forming tool (508, 510) for the press-forming of workpieces (150) and, in particular, downstream from the forming tool (510) for the press-forming and hot forming of workpieces (150).

15. The manufacturing device according to any one of claims 12 to 14, characterized in that the evaluation unit (300) and the control unit (320) are connected in a data-conducting manner, are functionally designed, and interact, in particular use corresponding software programs, so that the control unit (320) at least one unit and / or one device can be controlled and / or regulated at least intermittently based on the weighing data received from the evaluation unit (300), in particular at least one unit and / or one device upstream from the scale (200) can be controlled and / or regulated at least intermittently.

16. The manufacturing device according to any one of claims 12 to 15, characterized in that at least one forming station (506) and / or at least one forming tool (508, 510) is designed to form a group of two or more workpieces (150) and comprises release means and / or is designed to release and / or hold individual workpieces (150) and / or groups of workpieces (150) in a controlled manner.

17. A method for operating a manufacturing device (500) according to claim 12, comprising the steps: - providing a starting material (140) - introducing a starting material (140) into a forming unit (504), the forming unit (504) having at least one forming station (506) with at least one forming tool (508) and at least one pressing device (510), - forming at least one workpiece (150), in particular a group of workpieces (150), by means of the forming tool (508), characterized in that, downstream from the forming station (506), the total weight and the horizontal weight distribution of at least one workpiece (150) or workpiece stack (152) positioned on the carrier element (202) is detected by means of a scale (200) of a weighing system (100) in a weighing step, a group of two or more positioned workpieces (150) or workpiece stacks (152) being detected in particular, wherein, in the weighing step, weighing data are determined and sent to an evaluation unit (300), the evaluation unit (300) sending the weighing data to a control unit (320) and, based thereon and the use and / or integration of target value specifications, in particular algorithms, value tables, and / or Al, - at least one unit and / or one device is controlled and / or regulated at least intermittently and / or - at least one informational and / or warning signal is sent to an output unit, in particular an HMI, a visual or acoustic signal generator.

18. The method according to claim 17, characterized in that, after the joint forming of at least two workpieces (150), step-by-step weighing is carried out for a number of workpiece layers greater than or equal to 2, a layer-by-layer weighing of the workpieces (150) being carried out in particular.

19. The method according to claim 17, characterized in that after the joint forming of a group of at least two workpieces (150), multiple weighing is carried out before a next forming of a next group of workpieces (150) by independently weighing a subset of workpieces (150) of the jointly formed group (154) in partial weighings.

20. The method according to any one of claims 17 to 19, characterized in that the weighing step takes place after the first forming and an additional forming.

21. The method according to claims 19 to 20, characterized in that the weighing system (100) is designed according to any one of claims 1 to 11.