Method and apparatus for visualizing or evaluating process status

Abstract

The invention relates to a method for evaluating and / or visualizing a process state of a production plant (1) comprising at least one periodically operating forming machine (2), in which values of a plurality of selected process variables are determined in a time-continuous or time-discrete manner, and comparing the respective current value of each selected process variable or the variable derived therefrom with one or more reference values by means of the computing unit (4) and determining a deviation or rate of change, each selected process variable being assigned to at least one logic group by means of the computing unit (4), at least two different logic groups being provided, and for each logical group, evaluating and / or visualizing the state of the logical group by means of a computing unit (4) on the basis of the process variables associated with the logical group and by means of a display device (5).

Description

[0001] This application is a divisional application of the invention patent application with the application date of February 28, 2019, application number 201980027165.9, international application number PCT / AT2019 / 060066, and invention name “Method and device for visualizing or evaluating process status”. Technical Field

[0002] The invention relates to a method for visualizing or evaluating a process state, a computer program product, a visualization device for a production plant, an evaluation device for a production plant, and a production plant comprising such a visualization device and / or evaluation device. Background Art

[0003] Current visualization and evaluation devices for production plants of this type offer the possibility of displaying and / or monitoring hundreds of process variables determined from measured values ​​in the form of characteristic factors.

[0004] Such a characteristic factor can be, for example, a minimum value, a maximum value, a mean value or an integral of a measurement curve recorded within a periodic production process (production cycle).

[0005] Such a curve is typically a function of time. Other characteristic factors may also be the time (from the start of the measurement) at which the curve has a certain characteristic, i.e. the time of a maximum / minimum, the time when the integral exceeds a certain value, reaches, exceeds or falls below a limit value, etc.

[0006] Characteristic factors can also be derived from a combination of measurements with different sensors. If, for example, the screw position, injection pressure and mold pressure are measured during injection in a plastic injection molding machine, characteristic factors such as the screw position at which the maximum injection pressure is reached, the mold pressure in the first screw position, etc. can be determined by connecting the parameter "time".

[0007] For characteristic factors, first of all (in contrast to the case where actual values ​​of the assigned theoretical values ​​are usually given), no expected values ​​are given, but they are often derived from a number of factors. An example is the maximum injection pressure in plastic injection molding machines, which is derived primarily from the injection speed, the geometry of the mold gap, the melt viscosity and the mold temperature. This is why these variables are so interesting, because they can be used to infer influencing variables or their changes that cannot be measured or not directly measured.

[0008] The setpoint value is a setpoint value for a production device that is predetermined by an operator, simulation software, a setting aid or a process optimization system. It is typically a digital value (e.g. setpoint temperature, setpoint position, setpoint speed), a Boolean value (yes / no), a string or a related selection from a list.

[0009] Such a method and such a visualization device for a production plant including a cyclically operating molding machine in the form of a plastic injection molding machine are disclosed in DE 10 2007 013 044 B4. The plastic injection molding machine described therein has a machine control device which is designed so that in the operating state, different process parameters of the current injection molding cycle are compared with corresponding process parameters of at least one preceding injection molding cycle, wherein a stability parameter is formed from the changes in the different process parameters and a warning signal is displayed on a display device when the stability parameter exceeds a threshold value. Preferably, a warning system is used which is implemented by a visualized traffic light.

[0010] A disadvantage of this prior art is that, when a problem occurs, it is difficult to clarify the cause of the problem.

[0011] US 2004 / 148136 A1 teaches the visualization of data for a production site by means of a plurality of logical groups (cf. Figure 6 ), where each logical group contains a production machine. The data of the components of the production machine (cyclically operating molding machines and peripheral equipment) cannot be visualized or evaluated. Summary of the invention

[0012] The object of the present invention is to provide a method, a computer program product, a visualization device, an evaluation device and / or a production plant, in which the cause of a problem can be better evaluated and / or is easier to understand for an operator.

[0013] The method according to the invention allows a simple visualization and / or evaluation of process variables of a production plant by an operator or by a computing unit, wherein the production plant in a minimal configuration only comprises a cyclically operating molding machine, but in practice often also machines, devices and apparatuses (generally: peripherals) connected upstream and downstream of the molding machine or operating in parallel are provided. The factory-preset configuration of process variables to specific logical groups already provides a person skilled in the art with information about the causes of changes, which in turn facilitates troubleshooting.

[0014] It can be provided that the logical group is formed according to at least one criterion listed in the following list:

[0015] - equipment areas or components of a production plant (e.g. closing units, injection units, moulds, return locks, etc.),

[0016] - process steps or states of the production process,

[0017] - the characteristics of the forming material processed by the forming machine,

[0018] - the characteristics of the shaped parts produced by the forming machine,

[0019] - potential disruptions or failures in the production process,

[0020] - the existence of the desired state (e.g. "closing characteristics of the locking device are normal"),

[0021] - the productivity and economy of a production plant or process or its components,

[0022] - Environmental conditions of production equipment or processes or their components.

[0023] The grouping in logical groups can be done, for example, as follows:

[0024] - process steps of the production cycle,

[0025] - functional units of production equipment, in particular forming machines,

[0026] - physical variables of the production process or measures for preparation of the production process (e.g. preheating of components of a molding machine).

[0027] Particularly adapted to plastic injection molding machines, the logical groups can be formed or arranged as follows with respect to process steps, functional units or physical variables:

[0028] Logical groups of process steps regarding the production cycle may be (alone or in any combination):

[0029] - a logical grouping of the process step "drying and conveying the plastic material into at least one plasticizing unit of a plastic injection molding machine", for example called "drying and conveying",

[0030] a logical grouping of the process step "plasticizing the delivered plastic material in at least one plasticizing unit of a plastic injection molding machine", for example designated "plastic melting",

[0031] - a logical grouping of the process step "injecting plasticized plastic material into at least one cavity of a plastic injection molding machine", for example called "filling the mold",

[0032] - a logical grouping of the process step "cooling and removal and / or ejection of the shaped part produced by coagulation of the plasticized plastic material injected into the at least one cavity", for example designated "shaping and removal",

[0033] A logical grouping of the process step “closing and opening at least two mold parts of a plastic injection molding machine which are fastened to a molding platen and can form the at least one mold cavity” is called, for example, “closing and opening”.

[0034] The logical group “drying and conveying” can contain, for example, the process variables “temperature of plastic material”, “moisture content of plastic material”.

[0035] The logical group "plastic melting" can, for example, contain the process variables "temperature of the plasticized plastic material", "power of the temperature control device of the plasticizing unit", "dynamic pressure head in the screw front space of the plasticizing screw", "speed and / or torque of the plasticizing screw".

[0036] The logical group "Filling the mold" can contain, for example, the process variables "Injection pressure", "Screw feed speed of the plasticizing screw".

[0037] The logical group “forming and removal” may contain, for example, the process variables “pressure inside the mold”, “mold temperature”, “hot runner temperature”, “performance of the temperature control device of the mold”.

[0038] The logical group "Closing and opening" can, for example, contain the process variables "Closing force with which the mold parts can be pressed against one another by the forming platen during injection", "Closing force distribution", "Tear-off force with which the mold parts move away from one another after the shaped part has solidified", "Embossed stroke when using an embossing mold".

[0039] Logical groups of functional units concerning production equipment may be (alone or in any combination):

[0040] - logical group about "Plastic injection molding machine",

[0041] - a logical group about "Shutdown unit of a plastic injection molding machine",

[0042] - a logical group about "injection unit of a plastic injection molding machine",

[0043] - logical group about "Quick lifting device for closing unit",

[0044] - a logical group about the "closing mechanism of the closing unit",

[0045] - logical groups about "molds",

[0046] -Logical group about "mold ejection device",

[0047] - logical group about "temperature control device of mold",

[0048] - logical group about "Plasticizing unit of injection unit",

[0049] - logical group "Metering drive for plasticizing unit",

[0050] - logical group about "jet drive for plasticizing unit",

[0051] -Logical group concerning "Handling device for plastic injection molding machines".

[0052] Since it is clear to those skilled in the art how the variables discussed above with respect to logical groups for process steps can be configured with respect to logical groups for functional units, the corresponding explanation is omitted.

[0053] Logical groups of physical variables concerning the production process can be (alone or in any combination):

[0054] -Logical groups for "temperature", "pressure", "stroke", "volume", "speed", "velocity", "force", "time", "power", "torque", etc.

[0055] With regard to the method according to the invention, each selected process variable is assigned to at least one logical group, wherein at least two different logical groups are provided and for each logical group a state of the logical group is evaluated and / or visualized based on the process variable assigned to the logical group.

[0056] With regard to the visualization device or evaluation device setting according to the present invention, different logical groups can be visualized and / or evaluated, and each selected process variable is assigned to at least one of the logical groups, and for each logical group, the state of the logical group can be visualized and / or evaluated based on the process variable assigned to the logical group.

[0057] The visualization device or evaluation device according to the invention is preferably designed to implement the method according to the invention. It should be pointed out that, in order to keep the disclosure concise, all of the measures described with respect to the method according to the invention can of course also be provided in the visualization device or evaluation device according to the invention, either individually or in any combination.

[0058] The visualization device or evaluation device can exist as a single structural unit (and then preferably be arranged in the production plant) or in a decentralized form. In the latter case, individual or all components of the visualization device or evaluation device can be arranged at different locations remote from the production plant, for example in the form of a cloud solution. In this case, the visualization device or evaluation device must of course also have access to the process variables of the production plant, for example via a data teleconnection.

[0059] The visualization device may, for example, have a display device formed by a mobile device (smartphone, tablet computer, etc.) or a display device provided on the production system, a computing unit provided by a server in the cloud, and a storage medium formed in the cloud, the mobile device or the production system. This applies analogously to the evaluation device.

[0060] A molding machine which preferably operates in a cycle mode is understood within the meaning of the present invention to be a plastics injection molding machine.

[0061] Protection is also claimed for a production plant which comprises at least one cyclically operating forming machine and which has a visualization or evaluation device according to one of the described embodiments or which can be connected in data connection thereto.

[0062] That is, each production equipment has (preferably only one) periodically working forming machine. Periodically working forming machines can certainly have multiple periodically working subunits, especially multiple periodically working plasticizing and / or injection units. In this case, the cycle of the production equipment is understood as the following time period, which is generated when considering all periodically working subunits. Optionally, the production equipment also has machines, devices and instruments connected to the upstream and downstream of the forming machine or running in parallel, which can provide process variables respectively and are preferably equipped with sensors for determining measurement data. Examples for this are instruments and equipment (cooling and temperature regulators, material conveyors, metering and mixing equipment) for supplying forming machines or forming molds, instruments and equipment (dryers, dust collectors) for preparing raw materials, instruments (robots, conveyor belts, separation switch machines) for manipulating formed parts, equipment (optical image processing, balances, measuring devices) for quality inspection, equipment for further processing or processing formed parts, or systems for measuring additional process variables (pressure in the mold, temperature, mold permeability or stretching) from molds or environments.

[0063] By way of example, it is provided that an actual value, a setpoint value, a characteristic factor, a measured value curve, a variable calculated from a plurality of preceding values ​​such as a drift, a slope or a variance or an operating state is used as at least one selected process variable. Different examples can be used for different selected process variables.

[0064] The reference value may be any value which is used for comparison with the process variable. A specific reference value may be set for a plurality of process variables or a separate reference value may be set for each process variable. Preferably, at least one reference value is selected from the following list, wherein at least two or even all of the following list items may also be combined:

[0065] one or more temporally preceding values ​​of a selected process variable, for example an immediately temporally preceding value or a drift or a variance of a selected process variable,

[0066] - the value of the selected process variable stored by the operator at a specific time,

[0067] - values ​​calculated from multiple process variables,

[0068] - theoretical values ​​for the selected process variables,

[0069] - ideal values ​​for selected process variables determined by an expert system,

[0070] A variable, such as a drift or a variance, calculated from the current value of the selected process variable and / or from one or more temporally preceding values ​​of the process variable.

[0071] The combination of the above listed items can be called the reference state of the production process.

[0072] That is, according to the invention, the process variables of the current working cycle do not necessarily have to be compared with the process variables of the previous working cycle, but the process variables (which do not necessarily have to relate to the working process) can also be determined at certain time intervals. This makes it possible, for example, to observe heating processes in which no working cycles are running at all. In this case, the values ​​determined for the temperature or the volume flow of the temperature control medium are suitable bases for the characteristic factor, which is determined, for example, every 10 seconds.

[0073] Preferably, it is provided that the time-discrete determination of the values ​​of the plurality of selected process variables is performed in one of the following ways:

[0074] - for a series of periodic production processes, preferably in each periodic production process,

[0075] - determining a new value upon the occurrence of a predefined event, for example upon each occurrence of a predefined event,

[0076] - at predetermined intervals (e.g. a new value every x seconds).

[0077] The measures defined in the previous paragraphs may also be provided with respect to determining a deviation or a rate of change.

[0078] The following questions can be asked in the assessment of the process status:

[0079] -Does the process variable change, especially in the more recent past, in the form of a drift or abrupt change, or does it remain constant?

[0080] - Has the process variable changed since the reference value stored at the defined time?

[0081] - Are process variables changed by intervention by the user, process setter, process optimization system or by external influences?

[0082] - A certain process variable, in particular a setpoint value, should be changed because a certain characteristic factor is unfavorable based on stored expert knowledge or based on a comparison with the past?

[0083] The quality of the production process (process quality) is not directly related to the quality of the produced molded parts. However, it can be considered that good process quality forms the basis for the constant quality of molded parts. By observing the process quality, faults can be detected early, and in the event of deterioration, quality checks of the molded parts can be initiated, the results of which can be correlated with specific changes in the process quality for future evaluation. From these relationships, connections can be learned or provided as input to self-learning systems (machine learning).

[0084] It is particularly preferred that the logical groups are arranged on at least two hierarchical levels, so that at least one logical group on a lower hierarchical level is assigned to another logical group on a higher hierarchical level. By grouping and accumulating information, the method for a production system (including a molding machine of peripheral devices) can be universally extended to production cells, production plants or production sites.

[0085] For example, you can set

[0086] - in a (preferably uppermost) hierarchical level, selecting logical groups with respect to the process steps of a production cycle,

[0087] - in the lower (preferably next) hierarchical level, selecting logical groups according to functional units of the production plant,

[0088] In a further (preferably the lowest) hierarchical level, logical groups are selected according to physical variables.

[0089] That is, a logical group at an upper level may contain one or more logical groups at a lower level.

[0090] For example, it can be specially adapted to the plastic injection molding machine:

[0091] - The hierarchical level contains logical groups of choices regarding "process steps in the production cycle",

[0092] a lower hierarchical level for each logical group of the upper hierarchical level contains logical groups which are selected with regard to the “functional units of the production plant” but only for the functional units of the production plant which are involved in the corresponding process step,

[0093] A further lower hierarchical level for each logical group of an upper hierarchical level contains logical groups which are selected with regard to the “physical variables of the production process”, but only for physical variables which are relevant with regard to the selected functional unit.

[0094] It can be provided that, when a deviation of a group of characteristic factors exceeds a predetermined value, an action is triggered, such as, for example, a report is sent to an operator regarding the associated logical group.

[0095] The combination of the evaluations of the individual process variables at a plurality of hierarchical levels results in an overall overview of the state of the process, from which the operator can obtain the desired information along the hierarchical structure at different levels down to the individual process variables, or the visualization device can automatically display this information to the operator. The advantage of the evaluation with or without visualization is that the actions to be automatically carried out can be better defined.

[0096] Different algorithms can be used to determine the deviation or rate of change for a selected process variable. Example:

[0097] - moving average, filtering, smoothing of multiple values,

[0098] - variance of multiple values,

[0099] - maximum and minimum values ​​and the times of their occurrence,

[0100] - average value, integral,

[0101] - median,

[0102] - calculation of slopes for multiple values,

[0103] - detection of inflection points in the signal profile,

[0104] -Difference between the value and the reference value.

[0105] The results of the algorithm can be tested for relevance using thresholds. The thresholds can be, for example:

[0106] (a) stored as the result of an expert system or

[0107] (b) Obtained by a self-learning system

[0108] (c) Fixed pre-defined

[0109] (d) Determined based on machine variables or process variables according to calculation rules

[0110] (e) Based on empirical values

[0111] (f) Predetermined by user input.

[0112] Numerical examples for cases (a) and (b):

[0113] When calculating the slope of the cylinder temperature signal, a slope of 0.5 Kelvin / second is determined.

[0114] (a) The stored limit value for the correlation of the cylinder temperature slope is 0.3 K / s, so the rate of change is classified as a correlation.

[0115] (b) The rate of change of the storage temperature that occurs during running production. In 99% of the observed cases, the rate of change is less than 0.4 Kelvin / second, so that the currently determined value is classified as relevant.

[0116] In one embodiment of the invention, instructions are given to the operator for process optimization or error correction. These instructions can be stored as results of the expert system. Alternatively, the method can store actions set by the operator for correcting the detected deviations, i.e. learn them and make them available to the same operator or other operators for subsequent use or as recommendations to make them known.

[0117] In one embodiment of the invention, process optimization or fault elimination is automatically performed by automatically changing the settings of the production process and / or the production system (e.g. setpoint values) and / or interrupting production and / or triggering a spare parts order and / or notifying customer service.

[0118] A further dimension in the visualization and / or evaluation can be introduced in the form of observation planes, wherein the observation planes show the situation of the process state of the production process and / or the production system and more precisely show it over the limits of the logical groups.

[0119] In one embodiment of the invention, it is provided that the deviation or rate of change is determined and / or displayed along the observation plane. Only when one observation plane is normal (the process variable assigned to this observation plane is verified to be normal in terms of the deviation or rate of change with respect to the at least one reference value) is the deviation or rate of change determined and / or displayed with respect to the process variable of the next plane. Suitable observation planes may be:

[0120] - Status (heating, temperature control circuit connected?)

[0121] - Confidence of the actual value (is a plausible value provided? If not, the sensor may be faulty.)

[0122] - the (controlled) actual value reaches a steady state, i.e. approaches the associated setpoint value?

[0123] -Characteristic factor enters steady state?

[0124] - Characteristic factors similar to those in the reference state?

[0125] - Set quality (are there expert system based suggestions for improving process quality by changing the theoretical values?).

[0126] Furthermore, an observation plane can also be specified, with respect to which a deviation or a rate of change with respect to a process variable is determined and / or displayed, independently of how high or low the observation plane is set to be evaluated.

[0127] It is preferably provided that the result of the determination of the deviation or the rate of change is made available on a display device, for example a display on the production plant, a mobile device or a production control system, and is further processed and / or visualized there.

[0128] It is preferably provided that the general overview of the process states contains the starting point of the screen pages of the subject configuration of the control device, the production control system, the mobile device, etc. The starting point is a connection part, which enables a fast switch ("jump") between the screen pages. It is also preferably provided that the logical groups at the hierarchical level are selected so that each logical group can be configured with a screen page that can be visualized by means of a display device. When the screen pages that can be visualized by means of a display device correspond to a division into functional units (for example, the screen pages "injection", "metering", "mass cylinder heating", "mold opening", etc.), this is given, for example, in the above-mentioned logical group "functional units of the production plant". As an alternative to the "jump" relative to the connected view, it is of course also possible to integrate the detailed information that is relevant in the respective case into the overview view.

[0129] Preferably, it is provided that an automatic assessment is made as to whether a reference value should be written by the operator in the current state with respect to the selected process variable. This can depend on which observation plane has confirmed that the logic group is normal. This can apply to all logic groups or only to the logic groups involved by the determined reference value.

[0130] Preferably, it is provided that different reference values ​​and / or correlation values ​​are used depending on the instantaneous situation of the production plant (eg molding machine ready for production start, production start, molded part ready for use, etc.).

[0131] It can be provided that in the event of a predetermined deviation or rate of change, the operator is advised of the action to be taken or that the action to be taken is immediately and automatically implemented. The produced molded parts can be evaluated as rejects.

[0132] It can be arranged that in the event of a process change being identified in the future, the user can select a communication (alarm report, alarm light, SMS, e-mail, etc.).

[0133] It can be provided that the evaluation and / or visualization of the process profile of the last cycle of the production process is performed relative to one or more preceding cycles of the production process and / or relative to a process variable record stored at a user-defined time (the process variable naturally remains constant in time until it is changed or deleted, also referred to below as a reference value), preferably grouped according to process steps. The visualization can be performed, for example, in the form of a traffic light display or a target plate display.

[0134] The comparison of the process variable with the process variable of the last cycle or the last cycles can be carried out, for example, in such a way that a drift, a variance, a change in the variance, etc. is displayed. No user action is required for this. The monitored parameters and monitoring limits are predefined at the factory and / or are learned independently during the production process. Adaptation by the user is possible, but not necessary.

[0135] The comparison with the process variable (reference value) stored at a user-defined time can be performed, for example, in the following way: In order to be able to carry out the comparison, the user must determine the current or selected previous cycle of the production process as a reference cycle. The reference cycle can be set for all groups / parameters or for selected groups / parameters. Alternatively, the reference value can be entered manually. Before setting the reference value, the user can be informed whether the time is favorable or unfavorable for this. The time is favorable when no process change is detected based on the previous value.

[0136] The reference value can be stored, for example, in a partial data record of the production system or, more precisely, of the molding machine, so that it can be read in again the next time the same mold is equipped.

[0137] It can be provided that, in addition to the visualization of process changes, also the actual setpoint value changes or the system stops caused by the operating mode change are visualized.

[0138] With regard to the visualization displayed on a target board, it can be provided that a quadrant is assigned to each logical group of logic to be visualized in the coordinate system of the visualization target board.

[0139] Preferably, the deviations from the previous values ​​stored as a reference are shown together in the following form:

[0140] The standardized distance of a parameter from its associated stored value is symbolically represented in the target disk by the distance from the center point.

[0141] The parameter deviating from the stored reference value is more or less away from the midpoint according to the degree of its deviation. If the parameter does not change at this moment, it is visualized as a point. If the parameter changes at this moment, it is not visualized as a point, but as an arrow and more precisely in such a way that the direction of change relative to the stored reference value is visualized by the direction of the arrow relative to the midpoint. BRIEF DESCRIPTION OF THE DRAWINGS

[0142] Figure 1 A first embodiment of the present invention is shown for determining and visualizing changes in the value of a process variable relative to the more recent past;

[0143] Figure 2 A second embodiment of the invention for determining and visualizing deviations from a reference value is shown;

[0144] Figure 3 A third embodiment of the invention is shown which uses the knowledge of an expert system;

[0145] Figure 4 and Figure 5 A fourth embodiment of the present invention is shown, which filters information in an observation plane. Figure 4 The situation before the start of production on a plastic injection molding machine is shown by way of example, and Figure 5 Shows possible states during production;

[0146] Figures 6 to 9 A fifth embodiment of the present invention is shown. Figure 6 Traffic light display showing process changes, Figure 7 Target plate display showing process variations, Figure 8a Showing the change process diagram without curve, Figure 8b Explanation Figure 8a The meaning of the symbols can be seen in Fig. 9 Shown relative to Figure 8a Graph of the change process;

[0147] Fig.10 A production plant comprising a forming machine and a processing device is schematically shown. DETAILED DESCRIPTION

[0148] The first embodiment of the present invention ( Figure 1 ) - Determine and visualize changes in the value of a process variable relative to the more recent past:

[0149] The molding machine is called a plastic injection molding machine. However, the following embodiments are also applicable to other forms of molding machines.

[0150] The visualization program is structured hierarchically. The highest hierarchical level contains the logical group "process stability". In the lower hierarchical levels, the logical groups "machine", "granulate", "melt", "filling", "mold" and "molded part" are provided for evaluating the process stability. Each logical group of the upper hierarchical level is assigned at least one further logical group in the next lower hierarchical level. For example, the logical group "mold" contains the subgroups "heating", "temperature control", "movement" and "demolding".

[0151] The logic group "temperature control" is mainly configured with the characteristic factor Delta_T_1. This value describes the temperature difference between the forward flow and the return flow in the temperature control medium channel of the mold. This process variable is measured in each working cycle (cycle number). The slope is calculated by comparing each current value with the previous value. If the slope exceeds the reference value in the form of a stored limit value, this is evaluated as unstable and the logic group "temperature control" is provided with a warning symbol (shown here as an exclamation mark by way of example). Since the logic group "temperature control" is a grouping of the superordinate logic group "mold", the superordinate logic group also receives the warning exclamation mark symbol. The topmost hierarchical level contains the logic group "process stability" here, which is now also marked with an exclamation mark. The logic groups that are confirmed to be normal based on the process variables configured thereto are marked with a check mark.

[0152] In this way, changes compared to the more recent past, such as drifts, abrupt changes or increased variances, can be evaluated.

[0153] In the illustrated embodiment, color coding can also be provided in addition to the illustrated symbols for the check mark and the exclamation mark, i.e. the color green is associated with the check mark and the color red is associated with the exclamation mark. As an alternative to using symbols for marking, color coding can also be provided. Alternatively, only symbols, plain text prompts or a combination of symbols and text instructions (with additional color coding if necessary) can be provided. These embodiments are generally applicable to the present invention.

[0154] The second embodiment of the present invention ( Figure 2 ) - Determination and visualization of deviations from reference values:

[0155] The molding machine is a plastic injection molding machine. However, the following embodiments are also applicable to other forms of molding machines.

[0156] In this exemplary embodiment, a comparison is made with a reference state determined by the operator. The medium flow in the two temperature control circuits changes here.

[0157] The third embodiment of the present invention ( Figure 3 ) - Using the knowledge of expert systems:

[0158] The molding machine is a plastic injection molding machine. However, the following embodiments are also applicable to other forms of molding machines.

[0159] In this exemplary embodiment, the process variable “cushion” (=frontmost screw position during injection and re-extrusion) is compared with the lowest value stored in the form of knowledge of the expert system as a reference value and classified as too small.

[0160] The fourth embodiment of the present invention ( Figure 4 and 5 ) - Filter by viewing plane information:

[0161] The molding machine is a plastic injection molding machine. However, the following embodiments are also applicable to other forms of molding machines.

[0162] exist Figure 4 From left to right in the diagram, defined hierarchical logical groups ("machine", "granulate", "melt", "filling", "mold" and "molded part") are entered, to which defined setpoint values, actual values, state variables and characteristic factors are assigned. From bottom to top, viewing planes are shown, in which they are evaluated in sequence (from bottom to top) and different process states of the production process or the production system that may be of interest to the operator are evaluated and visualized.

[0163] Figure 4 The situation before the start of production on a plastic injection molding machine is shown by way of example. The heating is switched on, but the setpoint temperature has not yet been reached. The actual temperature values ​​of the machine (cylinder heating) and the mold move in the direction of the setpoint value. Only when the setpoint value is reached does the next step of evaluation - stabilization of the configured process variables - take place. The logical groups "granules", "melt", "filling" and "molded part" can only be evaluated in this state until the setpoint value does not change relative to the reference.

[0164] exist Figure 5 It is shown in the figure that during production (i.e. Figure 4 One or more process variables of the evaluation logic group "melt" move away from the value determined at the time of determining the corresponding reference value.

[0165] The process variable suitable for evaluating the logical group "filling" has a higher variance compared to the reference. The process variable suitable for evaluating the quality of the logical group "formed part" drifts in the direction of the reference value stored at the time of referencing.

[0166] The molding machine in the fifth embodiment of the present invention ( Figure 6-9 ) is constituted as a plastic injection molding machine. However, the following embodiments are also applicable to other forms of molding machines.

[0167] exist Figure 6 In the exemplary embodiment of the present invention, a traffic light display of the process changes of the last cycle in relation to the immediately preceding cycle (left diagram) and in relation to reference values ​​stored at a user-defined time (right diagram) is provided. Six logical groups are evaluated and visualized. They are grouped according to process steps (here, for example, "Drying and conveying", "Melting plastic", "Filling mold", "Cooling component", "Forming and removal", "Quality inspection"). The "Show process" button allows you to view the time course of each process individually (as in the Figure 8a, switching to the corresponding page). In this example, changes have been made with respect to the filling of the circle shown (e.g. in yellow). The "Settings" button allows you to select the display options for the visualization. For example, you can choose how many past cycles the evaluation and visualization should be based on. With the "Messaging" button, the user can select messaging (alarm report, alarm light, SMS, e-mail, etc.) for situations in which a process change is determined in the future. With the "Stored Values" button, you can enter, change or clear reference values ​​based on the comparison shown on the right. With the small boxes shown in the top row of the figure, you can select the visualization options by setting the check marks (in this case, two visualization options are selected). Figure 6 The visualization shows that in this example there are deviations from the previous values ​​(only) with respect to the logical group "molten plastic". A more precise analysis is available to the user by selecting the "Show process" button, by means of which the user switches to the Figure 8a on the page shown in .

[0168] exist Figure 7 In the embodiment of the invention, a target display of the process variation of the last cycle of the production process relative to the preceding and stored values ​​is selected. Four logical groups are visualized, wherein a quadrant is assigned to each logical group in the coordinate system shown.

[0169] In this example, deviations from the preceding values ​​stored as a reference are optionally shown together in the form described below:

[0170] The standardized distance of a parameter from its associated stored value is symbolically represented in the target disk by the distance from the center point.

[0171] The parameter deviating from the stored reference value is more or less away from the midpoint according to the degree of its deviation. If the parameter does not change at this moment, it is visualized as a point (two such points can be seen in the figure by way of example). If the parameter changes at this moment, it is not visualized as a point, but as an arrow and more precisely in such a way that the direction of change relative to the stored reference value is visualized by the arrow relative to the direction of the midpoint (four such arrows can be seen in the figure by way of example).

[0172] The comparison with the preceding value is therefore carried out in such a way that the parameter visualized as a point shows no deviation from the value it had in the preceding period or in the preceding periods.

[0173] A factory-preset and / or predefinable “tolerance” determines the deviation from a stored reference value starting at which the visualization takes place.

[0174] The summary and extent of the deviations are shown in the following format:

[0175] Parameters that are less than the permissible tolerance from the stored reference value are in the innermost circle of the target disk. If the parameter is in the target area and does not change, it is not shown for reasons of clarity. Each other circular ring symbolizes a distance with a predetermined tolerance. That is, if the parameter is in the outer white ring, it is out of tolerance by a factor of 3-4.

[0176] Instead of showing each parameter individually, in this example they are grouped in the following manner. In the process step "filling the mold", for example, 5 parameters are out of tolerance by a factor of 3-4. These values ​​are stable, i.e. do not change at this instant and are therefore visualized as points. The other three parameters are further away from their stored reference values ​​in this circle segment and are therefore visualized as arrows with a direction away from the center point. Of course, any other way of grouping is possible.

[0177] By pressing one of the "Show process" buttons, a diagram of the course of events is obtained within a defined time interval or over a defined number of cycles.

[0178] In this embodiment, only a comparison with a previous value can be selected. In such a case, all parameters are visualized as points.

[0179] exist Figure 8a In the embodiment of , a curve diagram without curves is shown: the course change relative to the previous value is shown over the last 40 cycles (of course, another number can also be set). Events that can involve multiple logical groups are shown as symbols in the top bar (on the common x-axis).

[0180] It can be seen that, for example, an operating mode change has occurred between cycle number 18539 and cycle number 18549 (visualized by a star). Between cycle number 18559 and cycle number 18569, the user has caused a target value change (visualized here by way of example by a smiley face).

[0181] The hierarchical logical grouping is carried out according to: process step - functional unit - physical variable. The hierarchy for the group "melting plastic" (as process step) is shown by way of example, including the groups "cylinder heating" and "metering" (as functional units) and the corresponding other groups "temperature" and "power" or "time" and "torque" (as physical variables). It can be seen that the setpoint value changes shown in the top bar are carried out with respect to the temperature of the cylinder heating. The shaded areas in "temperature" and "power" show alarms, which are generated based on the changes that occur. The same applies to the right area in the groups "time" and "torque" of the group "metering", while the left shaded area in the group "time" is a series of operating mode changes.

[0182] Figure 8b Explanation Figure 8aThe meaning of the symbols can be seen in .

[0183] You can set automatic preselection:

[0184] If the user switches to this page, only those logical groups or parameters are displayed which have changed within the set observation time interval (here 40 cycles). This means that an automatic preselection of the information that is relevant at this moment takes place. By activating the "Show all parameters" function, the user can also view the parameters that were stable within the observation time interval.

[0185] In the example, a process change is shown. Here, the parameter is compared with its recent past in each cycle. If, for example, the temperature changes from 220° C. to 230° C., the transition time interval is marked until a new stable temperature is reached.

[0186] The course change relative to the stored reference value is shown similarly. However, the difference is that the marking of the time range is only terminated when the state at the user-defined stored time is reached again.

[0187] The “Limits” button can be used to set or (if it was predefined at the factory) change the acceptable tolerances.

[0188] Fig. 9 The embodiment shows relative to Figure 8a The change process diagram includes the expanded curve area of ​​the physical variable "temperature":

[0189] The curve profile is shown with tolerances (limits) plotted as dashed lines. The tolerances are predefined at the factory but can be changed by the user. The tolerances can be determined for individual parameters or for parameter types (eg all temperatures, all cylinder temperatures, etc.).

[0190] The parameter selection can be arranged in such a way that a set of parameters to be monitored is predefined at the factory, but the monitoring of each parameter can be deactivated by the user.

[0191] exist Figures 6 to 9 The measures described in connection with the exemplary embodiments of the present invention may also be provided individually or in any combination.

[0192] The embodiments discussed above with respect to the visualization device apply equally with respect to the evaluation device if the visualization is not regarded as mandatory.

[0193] Fig.10 The schematic diagram shows a production plant 1 comprising a forming machine 2 and a processing device 3. A computer unit 4 and a storage medium 6 are connected to a display device 5 via a data connection 7 in order to form an evaluation device and / or a visualization device.

[0194] The display device 5 can be designed, for example, in the form of a screen of a machine control of the molding machine 2 and / or in the form of a web portal and / or in the form of a body-carrying visualization device, for example a handheld device such as a tablet or VR glasses.

[0195] Of course, the computing unit 4 and the storage medium 6 can also be part of the molding machine 2 other than as shown, for example part of a machine control system.

[0196] An evaluation program is stored in the storage medium 6 , wherein different logical groups can be formed by the evaluation program and each selected process variable is assigned to at least one of the logical groups, and for each logical group a state of the logical group can be evaluated based on the process variable assigned to the logical group.

[0197] Furthermore, a visualization program is stored in the storage medium 6 , wherein different logic groups can be visualized by means of the visualization program, each selected process variable is assigned to at least one of the logic groups, and for each logic group the state of the logic group can be visualized by means of the display device 5 based on the process variable assigned to the logic group.

[0198] List of reference numerals and terms used:

[0199] 1. Production Equipment

[0200] 2 Molding Machine

[0201] 3. Processing device

[0202] 4 Computing Units

[0203] 5 Display device

[0204] 6 Storage Media

[0205] 7Data Connection

[0206] Measured value: A value of a physical variable of a production plant, one of its components or of the material to be processed that is provided by a sensor or that is determined based on a signal provided by a sensor.

[0207] Process variable: A variable determined by a measurement, which can be expressed in the form of one or more characteristic factors.

[0208] Characteristic factor: a variable determined by a process variable, such as the characteristic of a measurement curve; the moment at which the measurement variable has a certain value, etc.

[0209] Theoretical value: The set value used for production equipment

[0210] Reference value: The value used to compare with the process variable

[0211] Reference state: A combination of reference values ​​that characterizes the state of a production device or its components at a certain moment in time.

[0212] Reference value: A special form of reference value, i.e. a process variable stored at a user-defined time for comparison with one or more process variables.

[0213] Tolerance: Specifies the value from which the deviation should be visualized and / or evaluated (eg in the form of a band around the curve).

Claims

1. A method for evaluating and / or visualizing process states of a production plant (1), the production plant comprising at least one cyclically operating forming machine (2), wherein: The values ​​of a plurality of selected process variables are determined continuously or discretely in time, and the respective current value of each selected process variable or a variable derived therefrom is compared with one or more reference values ​​by a calculation unit (4) and a deviation or a rate of change is determined, characterized in that each selected process variable is assigned to at least one logic group by the calculation unit (4), wherein at least two different logic groups are provided, and for each logic group, the state of the logic group is evaluated by the calculation unit (4) based on the process variable assigned to the logic group and / or the state of the logic group is visualized by means of a display device (5).

2. The method according to claim 1, wherein: As at least one selected process variable, an actual value, a setpoint value, a characteristic factor, a measured value curve, a variable calculated from a plurality of preceding values, such as a drift, a slope or a variance, or an operating state is used.

3. The method according to at least one of the preceding claims, wherein: When determining the deviation or change by the computer unit ( 4 ), it is taken into account whether a change has occurred by an operator, a process controller, a process optimization system or by external influences.

4. The method according to at least one of the preceding claims, wherein: Select at least one reference value from the following list, wherein at least two or all of the following list items can be combined: one or more temporally preceding values ​​of a selected process variable, for example an immediately temporally preceding value or a drift or a variance of a selected process variable, - the value of the selected process variable stored by the operator at a specific time, - values ​​calculated from multiple process variables, - theoretical values ​​for the selected process variables, - ideal values ​​for selected process variables determined by an expert system, A variable, such as a drift or a variance, calculated from the current value of the selected process variable and / or from one or more temporally preceding values ​​of the process variable.

5. The method according to at least one of the preceding claims, wherein: The time-discrete determination of the values ​​of the plurality of selected process variables and / or the determination of the deviation or the rate of change is performed in one of the following ways: - for a series of periodic production processes, preferably in each periodic production process, -When a pre-defined event occurs, - At predetermined time intervals.

6. The method according to at least one of the preceding claims, wherein: The logical group is formed according to at least one criterion listed in the following list: - equipment areas or components of a production plant (1), - process steps or states of the production process, - the properties of the shaped material processed by the shaping machine (2), - the characteristics of the shaped part produced by the shaping machine (2), - potential disruptions or failures in the production process, - the existence of a desired state, - Productivity and economy, - Environmental conditions.

7. The method according to at least one of the preceding claims, wherein: The logical groups are arranged in at least two hierarchical levels such that at least one logical group at a lower hierarchical level is assigned to another logical group at a higher hierarchical level.

8. The method according to the preceding claim, wherein: - in a preferably uppermost hierarchical level, selecting logical groups with respect to the process steps of a production cycle, - in a lower, preferably next, hierarchical level, selecting logical groups according to functional units of the production plant (1), In a further, preferably the lowest, hierarchical level, logical groups are selected according to physical variables.

9. The method according to at least one of the two preceding claims, wherein: The hierarchical logical groups are selected such that each logical group is assigned a screen page that can be visualized by means of a display device (5).

10. The method according to at least one of the preceding claims, wherein: At least two observation planes are used, one of which shows the situation of the production process and / or the process state of the production system and / or shows it beyond the limits of the logical group.

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