Quality estimation method, quality estimation device, and computer program

Abstract

To provide a quality estimation method capable of estimating the quality of a molded article by capturing the transition of time-series physical quantity data related to the operation of an injection molding machine.SOLUTION: Time-series physical quantity data related to the operation of an injection molding machine, the data being obtainable in an injection molding step of a molded article by using the injection molding machine, is acquired; the acquired physical quantity data is stored in a storage unit for each shot; quality data indicating the quality of the molded article obtained by injection molding when the acquired physical quantity data is acquired is stored in association with the physical quantity data; the quality of the molded article is calculated on the basis of physical quantity data acquired during estimation of the quality of the molded article and the physical quantity data and quality data stored in the storage unit; and prescribed processing is executed when the quality of the molded article becomes lower than prescribed quality.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present invention relates to a quality estimation method, a quality estimation apparatus, and a computer program.

Background Art

[0002] An injection molding machine that monitors the state of resin in an injection cylinder, detects the energy consumed for plasticizing the resin, and estimates the state of the resin in the injection cylinder based on the consumed energy to determine the molding quality is disclosed (for example, Patent Document 1). Specifically, the injection molding machine compares the detected consumed energy with a reference power amount that is a standard power amount consumed to produce a molded product of appropriate quality, and determines that there is a problem with the quality of the molded product when the difference exceeds a predetermined value.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in Patent Document 1, what is monitored to estimate the quality of a molded product is the upper and lower limit values of the consumed energy, and the transition thereof is not monitored. Although changes due to quality abnormalities of the molded product may appear in the transition of the monitored values, these changes may not be captured, and quality abnormalities of the molded product may not be detected.

[0005] An object of the present disclosure is to provide a quality estimation method, a quality estimation apparatus, and a computer program capable of capturing the transition of time-series physical quantity data related to the operation of an injection molding machine and estimating the quality of a molded product.

Means for Solving the Problems

[0006] A quality estimation method according to an aspect of the present disclosure acquires time-series physical quantity data related to the operation of an injection molding machine obtained in an injection molding process of a molded product using the injection molding machine, stores the acquired physical quantity data in a storage unit for each shot, and stores quality data indicating the quality of the molded product injection molded when the acquired physical quantity data is obtained in association with the physical quantity data. Based on the physical quantity data acquired during the quality estimation of the molded product, the physical quantity data and the quality data stored in the storage unit, the quality of the molded product is calculated. When the quality of the molded product is less than a predetermined quality, a predetermined process is executed.

[0007] A quality estimation device according to an aspect of the present disclosure is a quality estimation device including a processing unit. The processing unit acquires time-series physical quantity data related to the operation of an injection molding machine obtained in an injection molding process of a molded product using the injection molding machine, stores the acquired physical quantity data in a storage unit for each shot, and stores quality data indicating the quality of the molded product injection molded when the acquired physical quantity data is obtained in association with the physical quantity data. Based on the physical quantity data acquired during the quality estimation of the molded product, the physical quantity data and the quality data stored in the storage unit, the quality of the molded product is calculated. When the quality of the molded product is less than a predetermined quality, a predetermined process is executed.

[0008] A computer program according to an aspect of the present disclosure causes a computer to execute a process of acquiring time-series physical quantity data related to the operation of an injection molding machine obtained in an injection molding process of a molded product using the injection molding machine, storing the acquired physical quantity data in a storage unit for each shot, storing quality data indicating the quality of the molded product injection molded when the acquired physical quantity data is obtained in association with the physical quantity data, calculating the quality of the molded product based on the physical quantity data acquired during the quality estimation of the molded product, the physical quantity data and the quality data stored in the storage unit, and executing a predetermined process when the quality of the molded product is less than a predetermined quality.

Advantages of the Invention

[0009] According to the present disclosure, it is possible to provide a quality estimation method, a quality estimation apparatus, and a computer program that can capture the transition of time-series physical quantity data related to the operation of an injection molding machine and estimate the quality of a molded product.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Modes for Carrying Out the Invention

[0011] A quality estimation method, a quality estimation apparatus, and a computer program according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, and is intended to be indicated by the claims and to include all modifications within the meaning and scope equivalent to the claims. Also, at least a part of the embodiments described below may be arbitrarily combined.

[0012] FIG. 1 is a schematic diagram showing a configuration example of an injection molding system according to Embodiment 1. The injection molding system according to Embodiment 1 includes an injection molding machine 1, a logging device 6, and an information processing device (quality estimation device) 7.

[0013] <Injection molding machine 1> The injection molding machine 1 includes a mold clamping device 2 for clamping a mold 21, an injection device 3 for melting and injecting a molding material, a plurality of sensors 4, and a control device 5.

[0014] The mold clamping device 2 includes a fixed platen 22 fixed on a bed 20, a mold clamping housing 23 slidably provided on the bed 20, and a movable platen 24 that similarly slides on the bed 20. The fixed platen 22 and the mold clamping housing 23 are connected by a plurality of, for example, four tie bars 25, 25,.... The movable platen 24 is configured to be slidable between the fixed platen 22 and the mold clamping housing 23. A mold clamping mechanism 26 is provided between the mold clamping housing 23 and the movable platen 24. The mold clamping mechanism 26 is composed of, for example, a toggle mechanism. Note that the mold clamping mechanism 26 may be a direct pressure type mold clamping mechanism, that is, constituted by a mold clamping cylinder. A fixed mold 28 and a movable mold 27 are provided on the fixed platen 22 and the movable platen 24, respectively, and when the mold clamping mechanism 26 is driven, the mold 21 is opened and closed. Further, the mold clamping device 2 includes an ejector pin for taking out a molded product from the mold 21 and a drive motor for driving the ejector pin.

[0015] The injection device 3 is provided on a base 30. The injection device 3 includes a heating cylinder 31 having a nozzle 31a at its tip, and a screw 32 rotatably arranged in the heating cylinder 31 in the circumferential direction and the axial direction. A heater for melting the molding material is provided inside or on the outer periphery of the heating cylinder 31. The screw 32 is driven in the rotational direction and the axial direction by a drive device 35.

[0016] Near the rear end of the heating cylinder 31, a hopper 33 into which the molding material is charged is provided. Further, the injection molding machine 1 includes a nozzle touch device 34 that moves the injection device 3 in the front-rear direction (the left-right direction in FIG. 1). When the nozzle touch device 34 is driven, the injection device 3 advances so that the nozzle 31a of the heating cylinder 31 touches the contact portion of the stationary platen 22.

[0017] The plurality of sensors 4 are elements and circuits that detect physical quantities related to the quality of the molded product. In other words, the plurality of sensors 4 are elements and circuits that detect time-series physical quantities related to the operation of the injection molding machine 1 obtained in the injection molding process of the molded product using the injection molding machine 1.

[0018] The sensors 4 include those provided in the injection molding machine 1 as necessary for the operation control of the injection molding machine 1 and those separately provided for estimating the state of the injection molding machine 1. All or part of the plurality of sensors 4 are connected to the logging device 6, and the sensors 4 output signals indicating the detected physical quantities to the logging device 6. The information processing device 7 described later acquires physical quantity data from the sensors 4 via the logging device 6. The physical quantity data is data of time-series sensor values indicating the detected physical quantities. Also, a part of the plurality of sensors 4 is connected to the control device 5, and the information processing device 7 can also acquire physical quantity data from the sensors 4 via the control device 5.

[0019] The physical quantities include temperature, position, velocity, acceleration, current, voltage, pressure, time, image data, torque, force, strain, power consumption, weight, etc. These physical quantities can be measured using a thermometer, position sensor, velocity sensor, acceleration sensor, ammeter, voltmeter, pressure gauge, timer, camera, torque sensor, wattmeter, weighing scale, etc.

[0020] The plurality of sensors 4 include, for example, a velocity sensor that detects the velocity of the screw 32, a velocity sensor that detects the velocity of the movable platen 24, and a velocity sensor that detects the velocity of the ejector pin. The plurality of sensors 4 includes, for example, a torque sensor that detects the torque of the motor driving the screw 32, a torque sensor that detects the torque of the motor driving the movable platen 24, and a torque sensor that detects the torque of the motor driving the ejector pin. The plurality of sensors 4 includes, for example, a pressure sensor that detects the pressure in the screw 32 or the heating cylinder 31, and a pressure sensor that detects the pressure applied to the mold 21. The plurality of sensors 4 includes a load cell that detects the pressure applied in the longitudinal direction to the screw 32. The plurality of sensors 4 includes, for example, a position sensor that detects the position of the screw 32, a position sensor that detects the position of the movable platen 24, and a position sensor that detects the position of the ejector pin. The plurality of sensors 4 includes, for example, a rotational speed sensor that detects the rotational speed of the motor driving the screw 32, a rotational speed sensor that detects the rotational speed of the motor driving the movable platen 24, and a rotational speed sensor that detects the rotational speed of the motor driving the ejector pin. The plurality of sensors 4 includes a load sensor that detects the clamping force by the clamping device 2. The plurality of sensors 4 includes a temperature sensor that detects the temperature of the hopper 33, a temperature sensor that detects the temperature at one or more locations in the heating cylinder 31, and a temperature sensor that detects the temperature at one or more locations in the nozzle 31a.

[0021] In addition, the sensor 4 further includes any detector that can detect a physical quantity contributing to the estimation of the quality of the molded product.

[0022] The control device 5 is a computer that performs the operation control of the injection molding machine 1. The molding conditions for operating the injection molding machine 1 are set in the control device 5. The control device 5 outputs a command signal to the injection molding machine 1 and operates the injection molding machine 1 based on various set values indicated by the molding conditions and the detection values of the sensors 4.

[0023] The control device 5 also includes a communication unit (not shown) for transmitting and receiving information to and from the information processing device 7, an operation panel, and the like. Specifically, the control device 5 transmits data related to the molding conditions set in the injection molding machine 1 to the information processing device 7. The data related to the molding conditions is, for example, the name of the molding conditions for identifying the molding conditions set in the injection molding machine 1. The data related to the molding conditions may be the content of the molding conditions itself. The data related to the molding conditions is not particularly limited as long as the content of the molding conditions is reflected. Also, during the injection molding process, the control device 5 outputs a signal related to the command value based on the molding conditions to the logging device 6.

[0024] Furthermore, the control device 5 receives the estimation result regarding the quality of the molded product transmitted from the information processing device 7 and displays the received estimation result. Also, the control device 5 outputs an alert according to the estimation result of the quality of the molded product. Also, the control device 5 receives the information indicating the method of changing the set value related to the molding conditions transmitted from the information processing device 7 and displays the method of changing the set value.

[0025] The logging device 6 is, for example, a PLC (Programmable Logic Controller). The logging device 6 samples and AD-converts the analog signals output from the plurality of sensors 4 at a predetermined cycle, and stores them in the built-in memory as physical quantity data indicating the time-series physical quantities. Also, the logging device 6 samples and AD-converts the signal of the command value output from the control device 5 at a predetermined cycle, and stores it in the built-in memory as time-series command value data. For example, the logging device 6 stores the physical quantity data and the command value data as a CSV file. The logging device 6 transfers the file of the logged physical quantity data and command value data to the information processing device 7 every injection molding cycle. The physical quantity data is data related to the operation of the injection molding machine 1 and the quality of the molded product obtained in the injection molding process of the molded product using the injection molding machine 1.

[0026] <Information processing device 7> The information processing device 7 is a computer that estimates the quality or defect degree of a molded product manufactured by the injection molding machine 1. Further, when the quality of the molded product falls below a predetermined quality, the information processing device 7 performs an alert notification and executes a process of presenting a method for changing the set value of the molding conditions. The information processing device 7 executes a process of performing an alarm notification or proposing a change in the set value of the molding conditions when the quality of the molded product falls below a predetermined quality. The information processing device 7 includes a processing unit 71, a storage unit 72, an operation unit 73, an acquisition unit 74, a display unit 75, etc. as a hardware configuration. Note that the information processing device 7 may be a server device connected to a network. Further, the information processing device 7 may be configured by a plurality of computers for distributed processing, may be realized by a plurality of virtual machines provided in one server, or may be realized using a cloud server.

[0027] The processing unit 71 is a processor having an arithmetic circuit such as a CPU (Central Processing Unit), a multi-core CPU, a GPU (Graphics Processing Unit), a GPGPU (General-purpose computing on graphics processing units), a TPU (Tensor Processing Unit), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), an NPU (Neural Processing Unit), an internal storage device such as a ROM (Read Only Memory) and a RAM (Random Access Memory), an I / O terminal, a timing unit, etc. The processing unit 71 implements the quality estimation method according to the first embodiment by executing a computer program (program product) 72a stored in the storage unit 72 described later. Note that each functional unit of the information processing device 7 may be realized software-wise or partially or entirely may be realized hardware-wise.

[0028] The storage unit 72 is a non-volatile memory such as a hard disk, an EEPROM (Electrically Erasable Programmable ROM), or a flash memory. The storage unit 72 stores a computer program 72a for causing a computer to execute processes such as estimating the quality of a molded product. In addition, the storage unit 72 stores the time-series physical quantity data obtained from the injection molding machine 1 for each shot. The storage unit 72 stores a folder (hereinafter, the temporary storage folder 72b) for temporarily storing files of the physical quantity data acquired for each shot via the logging device 6, and a folder (hereinafter, the sorting folder 72c) for sorting the temporarily stored files according to the molding conditions and the data collection period.

[0029] The computer program 72a according to the first embodiment may be recorded on a recording medium 8 in a computer-readable manner. The storage unit 72 stores the computer program 72a read from the recording medium 8 by a reading device. The recording medium 8 is a semiconductor memory such as a flash memory. Further, the recording medium 8 may be an optical disc such as a CD (Compact Disc)-ROM, a DVD (Digital Versatile Disc)-ROM, or a BD (Blu-ray (registered trademark) Disc). Furthermore, the recording medium 8 may be a magnetic disk such as a flexible disk or a hard disk, or a magneto-optical disk. Still further, the computer program 72a according to the first embodiment may be downloaded from an external server connected to a communication network and stored in the storage unit 72.

[0030] The operation unit 73 is an input device such as a touch panel, soft keys, hard keys, a keyboard, or a mouse.

[0031] The acquisition unit 74 is a communication circuit that acquires physical quantity data output from the logging device 6 and command value data based on molding conditions. The acquisition unit 74 also communicates with the control device 5 to acquire data related to molding conditions and other data necessary for estimating the quality of the molded product.

[0032] The display unit 75 is a liquid crystal panel, an organic EL display, an electronic paper, a plasma display, or the like. The display unit 75 displays various information according to the image data given from the processing unit 71.

[0033] FIG. 2 is a flowchart showing a procedure for collecting reference data according to Embodiment 1. The processing unit 71 of the information processing apparatus 7 collects time-series physical quantity data and command value data related to the operation of the injection molding machine 1 obtained by detecting with a plurality of sensors 4 during the injection molding process of a molded product using the injection molding machine 1 (step S111). The physical quantity data is information for estimating the quality of the molded product. The process of step S111 is repeatedly executed, and physical quantity data over a plurality of injection molding cycles is collected.

[0034] FIG. 3 is a flowchart showing a data collection processing procedure according to Embodiment 1, FIG. 4 is a conceptual diagram showing a data collection method according to Embodiment 1, FIG. 5 is a conceptual diagram showing the content of a file stored by the data collection method according to Embodiment 1, and FIGS. 6 and 7 are charts showing an example of items of logging data.

[0035] When the molding process by the injection molding machine 1 is started, the logging device 6 starts logging time-series physical quantity data and command value data obtained by detecting with the sensor 4 (step S131). That is, the logging device 6 starts a process of storing a signal indicating a physical quantity output from a plurality of sensors 4 as time-series physical quantity data. The specific content of the physical quantity data will be described later. Further, the logging device 6 starts a process of storing a command value signal for operating the injection molding machine 1 as time-series command value data together with the physical quantity data.

[0036] Next, the logging device 6 determines whether or not the molding of one injection molding cycle has been completed (step S132). If it is determined that the one injection molding cycle has not been completed (step S132: NO), the logging device 6 continues logging the physical quantity data. If it is determined that the one injection molding cycle has been completed (step S132: YES), the logging of the physical quantity data and the command value data is terminated (step S133).

[0037] Then, the logging device 6 transfers the time-series physical quantity data for one shot to the information processing device 7 (step S134).

[0038] The information processing device 7 receives the files of the physical quantity data and the command value data transferred from the logging device 6, and saves the files including the received physical quantity data and command value data in the temporary storage folder 72b (step S151). Specifically, as shown in FIG. 4, when the information processing device 7 saves the files including the physical quantity data and the command value data in the temporary storage folder 72b, it starts saving the physical quantity data and the command value data as files with the first extension. When the saving of the physical quantity data and the command value data is completed, the extension of the files stored in the temporary storage folder 72b is changed from the first extension to the second extension. For example, the second extension is "csv", and the first extension has a name different from the second extension.

[0039] The file name of the file including the time-series physical quantity data and command value data for one shot is not particularly limited, but it is preferably to include the shot number. The physical quantity data and the command value data are stored in, for example, csv format. As shown in FIG. 5, as data items, the serial number "No." indicating the logging point, the date and year of logging, the time of logging, the elapsed time from the previous logging point to the current logging point (the unit is, for example, μs), and various command values and monitor values (physical quantities) output from the control device 5 to the injection molding machine 1 are associated and recorded.

[0040] Examples of the various command values, command values, and monitored values of physical quantities saved in the file include the data as shown in FIGS. 6 and 7. The "Command / Monitor Item" in the left column indicates the content of the command value output to the injection molding machine 1 and the content of the physical quantity detected. "Injection" and "Measurement" in each column indicate the command values and monitored values related to the operation of the screw 32, "Platen" indicates the command values and monitored values related to the operation of the mold clamping device 2, and "Eject" indicates the known position and monitored value related to the operation of the ejector pin for taking out the molded product from the mold 21. The items with a check indicate that there are command values or monitored values to be recorded.

[0041] Next, the processing unit 71 of the information processing apparatus 7 constantly monitors whether a file is stored in the temporary storage folder 72b, and determines whether a file with a second extension exists in the temporary storage folder 72b (step S152). If it is determined that there is no file with a second extension in the temporary storage folder (step S152: NO), the processing unit 71 continues to monitor the files stored in the temporary storage folder 72b.

[0042] If it is determined that there is a file with a second extension in the temporary storage folder (step S152: YES), the processing unit 71 acquires the current molding condition data from the injection molding machine 1 (step S153). The molding condition data is data indicating the molding conditions limitedly set in the injection molding machine 1, the molding condition name given to the molding conditions, and other data representing the molding conditions. The molding conditions set in the injection molding machine 1 vary depending on the molded product, and when the molding conditions are different, the content of the physical quantity data collected from the injection molding machine 1 also changes. The information processing apparatus 7 acquires the molding condition data in order to separately store the physical quantity data for each molding condition.

[0043] Next, the processing unit 71 determines whether a separate folder 72c having a folder name including a character string reflecting the molding conditions and the collection period of the physical quantity data has been created as a folder for storing the physical quantity data in the temporary storage folder 72b (step S154).

[0044] When it is determined that the separate folder 72c has not been created (step S154: NO), the processing unit 71 creates a folder having a folder name including a character string reflecting the molding conditions and the collection period of the physical quantity data as a folder for storing the physical quantity data (step S155). For example, the folder name may be "molding condition name / YYYY / MM / DD / collection start time - collection end time". "Molding condition name" is the name given to the molding conditions set in the injection molding machine 1. "YYYY", "MM", and "DD" indicate the year, month, and day when the physical quantity data was collected. "Collection start time" and "collection end time" indicate the times (start time and end time) when the physical quantity data to be stored in the folder was collected. The time interval between the collection start time and the collection end time is not particularly limited. The collection end time may be set as follows, for example. In the first example, the processing unit 71 sets the timing when the molding conditions are changed as the collection end time. In the second example, when 30 minutes or more have elapsed since the most recent shot, the processing unit 71 sets the time point 30 minutes after the start as the collection end time. In the third example, the processing unit 71 sets a predetermined collection period such as 30 minutes. In the first and third examples, since the collection end time is not determined during the collection of the physical quantity data, it is advisable to use a temporary name for the folder name. For example, the processing unit 71 may use a folder with a temporary name such as "curent", or may leave only the collection end time blank. The method of naming the temporary name is not particularly limited.

[0045] Here, an example in which the molding condition name is included as the name of the separate folder 72c has been described, but it may be configured to include characters reflecting the molding conditions set in the injection molding machine 1. For example, instead of the molding condition name, characters representing the content of the molding conditions may be used. In short, it is sufficient if the molding conditions set in the injection molding machine 1 can be identified.

[0046] When it is determined in step S154 that the sorting folder 72c has been created (step S154: YES), or when the processing unit 71 has completed the process of step S155, the processing unit 71 moves the files with the second extension stored in the temporary storage folder 72b to the sorting folder 72c corresponding to the molding conditions and the data collection period (step S156), and ends the process. That is, the processing unit 71 moves and stores the physical quantity data obtained when injection molding is performed under the molding conditions included in the folder name of the sorting folder 72c for each shot to the sorting folder 72c according to the collection period included in the folder name of the sorting folder 72c. Note that the process of step S156 is an example of a process of storing the acquired physical quantity data in the storage unit 72 in association with the molding conditions set in the injection molding machine 1 for each shot.

[0047] Returning to FIG. 2, the processing unit 71 acquires quality data indicating the quality of the molded product manufactured by the injection molding machine 1 (step S112). The method of acquiring the quality data is not particularly limited. The operator may visually determine the quality of the molded product and input the determination result into the information processing apparatus 7, or the computer may be configured to determine the quality of the molded product using a camera, a position sensor, a weight sensor, or the like.

[0048] Then, the processing unit 71 stores in association with the file of the physical quantity data the quality data indicating the quality of the molded product injection molded when the stored physical quantity data was obtained (step S113). For example, the processing unit 71 stores a quality data file associating the shot number and the quality data in the sorting folder 72c. Note that the method of associating each file stored in the sorting folder 72c with the quality data is an example, and the method of associating the data is not particularly limited. The quality data may be recorded in the file of the physical quantity data, or the quality data may be recorded as the properties or other attribute information of the file.

[0049] FIG. 8 is a flowchart showing the processing procedure of quality estimation according to Embodiment 1. The processing unit 71 of the information processing apparatus 7 collects time-series physical quantity data related to the operation of the injection molding machine 1 obtained by detection with a plurality of sensors 4 during the injection molding process of a molded product using the injection molding machine 1 (step S171).

[0050] Then, the processing unit 71 reads out reference data at the time of good products, for which the molding conditions are common when the collected physical quantity data is obtained, from the storage unit 72 (step S172). The reference data at the time of good products is physical quantity data in which the quality indicated by the quality data is equal to or higher than a specific standard indicating good products among the files stored in the sorting folder 72c.

[0051] Next, the processing unit 71 compares the time-series waveform indicated by the physical quantity data acquired during the quality estimation of the molded product with the time-series waveform indicated by the read reference data, and calculates the difference between the time-series waveforms as the quality of the molded product (step S173). The difference is, for example, the sum of squared errors of the time-series waveforms. More preferably, it is advisable to compare the time-series waveforms during a period in which the processes constituting the injection molding cycle are common. The processing unit 71 can specify the time in one cycle of each process constituting the injection molding process by referring to the molding conditions. The processing unit 71 can extract the time-series waveform corresponding to the specified time of each process from the time-series waveforms in one cycle. The processing unit 71 can estimate the quality of the molded product more accurately by comparing the time-series waveforms of the same process.

[0052] Next, the processing unit 71 determines whether the calculated quality is less than a predetermined quality (step S174). When it is determined that the quality of the molded product is less than the predetermined quality (step S174: YES), an alarm notification process (predetermined process) is executed (step S175). That is, the processing unit 71 notifies the operator by voice, lighting, etc. that the quality of the molded product has deteriorated. The alert method is not particularly limited, and the processing unit 71 may transmit a signal for notifying the alert to the control device 5. Further, the processing unit 71 may be configured to transmit a signal for notifying the alert to the terminal possessed by the operator.

[0053] Next, the processing unit 71 specifies a method for changing the set value related to the molding conditions based on the physical quantity data acquired during quality estimation and the physical quantity data stored in the storage unit 72 (step S176), and displays the specified method for changing the set value on the display unit 75 (step S177). For example, the time-series waveform of the physical quantity data detected during quality control and the time-series waveform of the reference data are compared for each item of the detected physical quantity, the physical quantity with a large difference is specified, and it is displayed on the display unit 75 that the physical quantity is larger or smaller than the reference data, or it is displayed via the control device 5. Note that the processing unit 71 may be configured to transmit the method for changing the set value of the molding conditions to the control device 5 and display it on the display of the control device 5.

[0054] Note that the process shown in FIG. 8 shows a process of estimating the quality of one molded product based on the physical quantity data for one shot. However, the processing unit 71 can monitor the quality of the molded products mass-produced by repeating the process shown in FIG. 8 during the molding process by repeating the injection molding cycle.

[0055] As described above, according to the injection molding system according to the first embodiment, the physical quantity data obtained for each shot in the injection molding process can be stored in association with the molding conditions and the data collection period. By associating with the molding conditions and the data collection period, the physical quantity data can be easily utilized.

[0056] In addition, by creating a sorting folder 72c having a folder name indicating a character string related to molding conditions and a data collection period, and saving the file of the physical quantity data corresponding to the sorting folder 72c, it becomes easier to search for and refer to the physical quantity data that is the result of injection molding performed in the past, and it is possible to more efficiently utilize the physical quantity data.

[0057] As for utilization, for example, by comparing the physical quantity data obtained during quality control with the past physical quantity data collected under the same conditions and in a similar period, similar physical quantity data can be identified. If the quality data of the molded product is associated with the past physical quantity data, the quality of the molded product can be estimated by comparing the physical quantity data.

[0058] In addition, the information processing apparatus 7 of the first embodiment can more accurately identify similar physical quantity data and estimate the quality of the molded product by comparing the time-series waveforms of the parts common to the processes constituting the injection molding cycle among the time-series waveforms indicated by the physical quantity data.

[0059] In addition, since the command value is associated with the monitor value and saved in the file, when the molding conditions and the physical quantity data are similar and the quality data is good, the file at that time can be specified, and based on the command value at this time, the method of changing the set value based on the current molding conditions can also be estimated.

[0060] Furthermore, by comparing the physical quantity data, when the quality of the molded product falls below a predetermined quality, an alert can be output to notify the operator of an abnormality in the molding.

[0061] In addition, when transferring the file of the logged physical quantity data to the information processing device 7, saving it in the temporary storage folder 72b, and sorting it into the sorting folder 72c, it is possible to reliably perform file movement by changing the extension. Specifically, it is possible to determine whether the physical quantity data is being transferred based on the file extension, and after confirming that the file transfer is completed, the file in the temporary storage folder 72b can be moved to the sorting folder 72c.

[0062] In addition, in the first embodiment, an example of logging command value data together with physical quantity data has been described, but it may be configured to log and save only the physical quantity data and estimate the quality of the molded product.

[0063] (Second Embodiment) The injection molding system according to the second embodiment has a quality estimation processing procedure different from that of the first embodiment. Since the other configurations of the injection molding system are the same as those of the injection molding system according to the first embodiment, the same reference numerals are given to the same parts, and detailed descriptions are omitted.

[0064] FIG. 9 is a flowchart showing the processing procedure of quality estimation according to the second embodiment. The processing of steps S271 to S272 and steps S274 to S277 shown in FIG. 9 is the same as the processing of steps S171 to S172 and steps S174 to S177 of the first embodiment, and only the quality estimation processing is different.

[0065] The processing unit 71 of the information processing device 7 according to the second embodiment determines the quality of the molded product by comparing the increase / decrease or periodic change of the feature amount based on the physical quantity data obtained during quality control collected in step S271 with the increase / decrease or periodic change of the feature amount based on the reference data (step S273). For example, the processing unit 71 calculates the similarity of the increase / decrease or periodic change of the feature amount as the quality of the molded product. The quality of the molded product may be calculated such that the higher the similarity with the reference data at the time of a good product, the higher the quality of the molded product, and the lower the similarity, the lower the quality of the molded product.

[0066] According to the injection molding system according to Embodiment 2 configured as described above, in the same manner as in Embodiment 1, it is possible to estimate the quality of the molded product by utilizing past physical quantity data.

[0067] Means for solving the problems of the present disclosure are appended. (Appendix 1) Acquire time-series physical quantity data related to the operation of the injection molding machine obtained in the injection molding process of the molded product using the injection molding machine, Store the acquired physical quantity data in the storage unit for each shot, Associate and store quality data indicating the quality of the molded product injection molded when the acquired physical quantity data is obtained with the physical quantity data, Calculate the quality of the molded product based on the physical quantity data acquired during the quality estimation of the molded product, the physical quantity data stored in the storage unit, and the quality data, When the quality of the molded product is less than a predetermined quality, execute a predetermined process Quality estimation method. (Appendix 2) Calculate the quality of the molded product based on the difference between the time-series waveform indicated by the physical quantity data acquired during the quality estimation and the time-series waveform indicated by the physical quantity data stored in the storage unit The quality estimation method described in Appendix 1. (Appendix 3) Calculate the quality of the molded product based on the difference between the time-series waveforms indicated by a plurality of physical quantity data common to the processes constituting the injection molding cycle The quality estimation method described in Appendix 1 or Appendix 2. (Appendix 4) Store the physical quantity data in the storage unit in association with the molding conditions set in the injection molding machine, Calculate the quality of the molded product based on the difference between the time-series waveforms indicated by a plurality of physical quantity data with common molding conditions The quality estimation method described in any one of Appendices 1 to 3. (Appendix 5) Create a folder having a folder name including a character string reflecting the molding conditions set in the injection molding machine and the collection period of the physical quantity data, For the collection period included in the folder name, the physical quantity data obtained when injection molding is performed under the molding conditions included in the folder name is saved in the folder for each shot. The quality estimation method according to any one of Appendices 1 to 4. (Appendix 6) Save the physical quantity data as a file that associates the date when injection molding was performed, the time, the time information for specifying the detection time point of the physical quantity data, the acquired physical quantity data, and the command value related to the operation of the injection molding machine when the physical quantity data was acquired. The quality estimation method according to any one of Appendices 1 to 5. (Appendix 7) Based on the physical quantity data acquired during quality estimation and the physical quantity data stored in the storage unit, specify a method for changing the set value related to the molding conditions. The quality estimation method according to any one of Appendices 1 to 6. (Appendix 8) The predetermined process includes a process related to alarm notification. The quality estimation method according to any one of Appendices 1 to 7. (Appendix 9) Estimate the quality of the molded product by comparing the increase or decrease or periodic change of the feature quantity calculated based on the physical quantity data acquired during quality estimation with the increase or decrease or periodic change of the feature quantity calculated based on the physical quantity data stored in the storage unit. The quality estimation method according to any one of Appendices 1 to 8.

Explanation of Signs

[0068] 1: Injection molding machine 2: Mold clamping device 3: Injection device 4: Sensor 5: Control device 6: Logging device 7: Information processing device 8: Recording medium 20: Bed 21: Mold 22: Fixed platen 23: Mold clamping housing 24: Movable plate 25: Tyre 26: Molding clamping mechanism 27: Movable mold 28: Fixed mold 30: Base 31: Heating cylinder 31a: Nozzle 32: Screw 33: Hopper 34: Nozzle touch device 35: Driving device 71: Processing unit 72: Memory unit 72a: Computer program 72b: Temporary storage folder 72c: Sorting folder 73: Operation unit 74: Acquisition unit 75: Display unit

Claims

1. Obtaining time-series physical quantity data related to the operation of the injection molding machine, which is obtained in the injection molding process of a molded product using an injection molding machine, Storing the obtained physical quantity data in a storage unit for each shot, Associating and storing quality data indicating the quality of the molded product injection-molded when the obtained physical quantity data is obtained with the physical quantity data, Calculating the quality of the molded product based on the physical quantity data obtained during the quality estimation of the molded product, the physical quantity data stored in the storage unit, and the quality data, When the quality of the molded product is less than a predetermined quality, executing a predetermined process A quality estimation method.

2. Calculating the quality of the molded product based on the difference between the time-series waveform indicated by the physical quantity data obtained during the quality estimation and the time-series waveform indicated by the physical quantity data stored in the storage unit The quality estimation method according to Claim 1.

3. Calculating the quality of the molded product based on the difference between the time-series waveforms indicated by a plurality of physical quantity data common to the processes constituting the injection molding cycle The quality estimation method according to Claim 2.

4. Storing the physical quantity data in the storage unit in association with the molding conditions set in the injection molding machine, Calculating the quality of the molded product based on the difference between the time-series waveforms indicated by a plurality of physical quantity data with common molding conditions The quality estimation method according to Claim 2.

5. Creating a folder having a folder name including a character string reflecting the molding conditions set in the injection molding machine and the collection period of the physical quantity data, Saving the physical quantity data obtained when injection molding is performed under the molding conditions included in the folder name in the folder for each shot during the collection period included in the folder name The quality estimation method according to Claim 4.

6. Store the physical quantity data as a file that associates the date of injection molding, the time, the time information for specifying the detection time of the physical quantity data, the acquired physical quantity data, and the command value related to the operation of the injection molding machine when the physical quantity data was acquired. The quality estimation method according to claim 5.

7. Based on the physical quantity data acquired during quality estimation and the physical quantity data stored in the storage unit, specify a method for changing the set value related to the molding conditions. The quality estimation method according to any one of claims 1 to 6.

8. The predetermined process includes a process related to alarm notification. The quality estimation method according to claim 1 or claim 2.

9. By comparing the increase or decrease or periodic change of the feature quantity calculated based on the physical quantity data acquired during quality estimation with the increase or decrease or periodic change of the feature quantity calculated based on the physical quantity data stored in the storage unit, estimate the quality of the molded product. The quality estimation method according to claim 1 or claim 2.

10. A quality estimation device including a processing unit, The processing unit, Acquire time-series physical quantity data related to the operation of the injection molding machine obtained in the injection molding process of the molded product using the injection molding machine, Store the acquired physical quantity data in the storage unit for each shot, Store the quality data indicating the quality of the molded product injection molded when the acquired physical quantity data was obtained in association with the physical quantity data, Calculate the quality of the molded product based on the physical quantity data acquired during quality estimation of the molded product, the physical quantity data and quality data stored in the storage unit, When the quality of the molded product falls below a predetermined quality, execute a predetermined process. Quality estimation device.

11. Acquire time-series physical quantity data related to the operation of an injection molding machine obtained in the injection molding process of a molded product using the injection molding machine, Store the acquired physical quantity data in a storage unit for each shot, Associate and store quality data indicating the quality of the molded product injection molded when the acquired physical quantity data was obtained with the physical quantity data, Calculate the quality of the molded product based on the physical quantity data acquired during the quality estimation of the molded product, the physical quantity data stored in the storage unit, and the quality data, When the quality of the molded product is less than a predetermined quality, execute a predetermined process A computer program for causing a computer to execute the process.

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