Injection molding control device and injection molding machine

Abstract

An injection molding control device according to one embodiment of the present disclosure is used for controlling a heater in an injection molding machine having a cylinder, one or more heaters for heating the cylinder, and one or more detectors for detecting a state value, the injection molding control device comprising: a data set storage unit; the storage unit stores a plurality of data sets each including one or more limit setting values for limiting the maximum output of the heater. An information acquisition unit that acquires operation information, which is at least one of information indicating the state of the injection molding machine and information input by a user; a dataset selection unit that selects one dataset from the plurality of datasets on the basis of the one or more pieces of operation information acquired by the information acquisition unit; and a heater control unit that limits the output of the heater in accordance with the data set selected by the data set selection unit.

Description

Technical Field

[0001] The invention relates to an injection molding control device and an injection molding machine. Background Art

[0002] Injection molding machines are widely used. A screw is installed inside a barrel (a material barrel). The rotation of the screw melts the resin while conveying it through the barrel. The molten resin is then injected into a mold, forming a resin molded object. Injection molding machines, a heater is typically used to heat the barrel to a temperature suitable for the process.

[0003] Heaters used in injection molding machines have a lifespan, and as the temperature of the heater increases, the lifespan of the heater tends to shorten. Therefore, a method of limiting the output of the heater so that the temperature of the heater does not exceed a set temperature has been proposed (for example, see Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2012-236349 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] Providing a sensor to monitor heater temperature to ensure heater life increases costs. Furthermore, simply setting a maximum heater temperature limit prevents optimal control under various conditions. For example, the presence or absence of insulation to insulate the barrel can affect heater wear and injection molding quality. Therefore, a technology that can appropriately control heaters under various conditions is desired.

[0009] Solutions for solving problems

[0010] An injection molding control device according to one embodiment of the present disclosure is used to control the heater in an injection molding machine having a barrel, one or more heaters for heating the barrel, and one or more detectors for detecting status values. The injection molding control device includes: a data set storage unit that stores a plurality of data sets each including one or more limit setting values ​​for limiting the maximum output of the heater; an information acquisition unit that acquires operating information, the operating information being at least either information indicating the status of the injection molding machine or information input by a user; a data set selection unit that selects one data set from the plurality of data sets based on the one or more operating information acquired by the information acquisition unit; and a heater control unit that limits the output of the heater according to the data set selected by the data set selection unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram showing the structure of the injection molding machine according to the first embodiment of the present disclosure. DETAILED DESCRIPTION

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Figure 1 1 is a schematic diagram showing the structure of an injection molding machine 1 according to an embodiment of the present disclosure. The injection molding machine 1 includes a molding machine body 10 and an injection molding control device 20, which is itself an embodiment of the present disclosure.

[0013] The molding machine body 10 includes: a barrel (material barrel) 11; one or more screws 12 arranged in the barrel 11; a nozzle 13, which is arranged at the front end of the barrel 11; a supply feeder 14, which is arranged on the base end side of the barrel 11; one or more heaters 15 for heating the barrel 11 and the nozzle 13; one or more temperature sensors 16 for detecting the temperature of the barrel 11 and the nozzle 13 as a status value indicating the status of the injection molding machine 1; one or more removable heat-insulating parts 17 covering the barrel 11; and one or more installation detectors 18 for detecting whether the heat-insulating part 17 is installed as a status value other than the temperature indicating the status of the injection molding machine 1.

[0014] The barrel 11 has an inner cavity 111, which accommodates the screw 12 and serves as a flow path for the resin. The barrel 11 has a main supply port 112, to which the resin as the main raw material is supplied from the supply feeder 14. The barrel 11 may also have a supply port (not shown) for supplying auxiliary raw materials, additives, etc. The screw 12 is driven to rotate by the motor 121, and the resin supplied to the inner cavity 111 is pressurized to move it to the nozzle 13. The nozzle 13 defines a flow path for injecting resin into a mold not shown. The supply feeder 14 supplies granular resin to the inner cavity 111 through the main supply port 112. The heater 15 can be formed by a resistive heating element. In order to individually control the output of the heater 15, it is preferred to provide a temperature sensor 16 corresponding to each heater. The heat insulating member 17 can be used to suppress the diffusion of heat from the barrel 11 to the environment. The heat insulating member 17 can be divided into a plurality of parts for arrangement. The installation detector 18 independently detects the installation of the heat insulating member 17. The installation detector 18 can be formed of, for example, a limit switch or the like.

[0015] The injection molding control device 20 controls the screw 12, the feeder 14, the heater 15, etc. of the molding machine body 10. The injection molding control device 20 can be composed of one or more computer devices having a processor, a memory, etc. and executing an appropriate control program.

[0016] The injection molding control device 20 includes a dataset storage unit 21, an information acquisition unit 22, a dataset selection unit 23, a heater control unit 24, a dataset synthesis unit 25, and a dataset creation unit 26. The injection molding control device 20 is also connected to an input device 27 for user input.

[0017] The dataset storage unit 21 stores a plurality of datasets each including one or more limit setting values ​​for limiting the maximum output of the heater 15 during operation. Examples of limit setting values ​​include an output upper limit value, an output rate (ratio relative to a rated value) upper limit value, a current upper limit value, a resistance upper limit value, and an output density upper limit value. Furthermore, the dataset may include PID parameters and the like as limit setting values. In addition to limiting the direct upper limit values ​​described above, PID parameters can also limit the maximum actual output value by specifying an allowable degree of overshoot, etc. The dataset storage unit 21 can store datasets input via the input device 27, datasets created by the dataset synthesis unit 25, and datasets created by the dataset creation unit 26.

[0018] As shown in Table 1, the multiple datasets stored in the dataset storage unit 21 include datasets with different limit setting values ​​(output rates), for example, high-output datasets with relatively large maximum outputs based on the limit setting values, and datasets for extending the life of the machine based on relatively small maximum outputs based on the limit setting values. It is particularly preferred that the multiple datasets stored in the dataset storage unit 21 include an open-time dataset (dataset 0), which is one or more high-output datasets selectable when the barrel 11 is not equipped with a heat-insulating element 17, and one or more heat-insulating datasets (dataset 1), which are datasets for extending the life of the machine based on a heat-insulating element 17. A limit setting value may also be set for each heater 15 (three barrel heaters are set in Table 1). The maximum output based on the limit setting value of the heat-insulating dataset is smaller than the maximum output based on the limit setting value of the open-time dataset. In other words, the heat-insulating dataset is a dataset for extending the life of the machine based on a relatively small maximum output based on the limit setting value.

[0019] [Table 1]

[0020]

[0021] The dataset storage unit 21 may include selection criteria that determine the conditions for selecting a dataset, or may separately store a reference table that associates each dataset with the dataset selection criteria. Furthermore, the dataset storage unit 21 may store, as part of the dataset or as external data, the priority of the datasets that should be selected when multiple dataset selection criteria are met. The multiple datasets stored in the dataset storage unit 21 may include a first dataset that can be selected when a first selection criterion is met, and a second dataset that can be selected when a second selection criterion is met. Preferably, the multiple datasets also include a standard dataset that is selected when neither the first nor the second selection criteria are met. In Table 1, dataset 0 can be the standard dataset, dataset 1 can be the first dataset, and dataset 2 can be the second dataset. In this case, the standard dataset includes a limit setting value that maximizes the maximum output in actual use, and the first and second datasets include limit setting values ​​that reduce the maximum output below the maximum output of the standard dataset. The first and second selection criteria are conditions for relatively reducing the maximum output based on the limit setting values. As an example, assume that the first selection criterion is the installation of the heat insulation unit 17, and the second selection criterion is the selection of the power reduction mode based on input from the input device 27.

[0022] The information acquisition unit 22 acquires operating information, which is at least one of information indicating the state of the injection molding machine and information input by the user. Examples of operating information indicating the state of the injection molding machine include the detection value of the temperature sensor 16, the presence or absence of the heat insulating material detected by the installation detector 18, and the output value of the heater 15 (output of the heater control unit 24). Examples of operating information input by the user include the operating mode selected by input using the input device 27.

[0023] The dataset selection unit 23 selects one dataset from the multiple datasets based on the one or more pieces of operating information acquired by the information acquisition unit 22. Specifically, the dataset selection unit 23 selects a dataset associated with a selection criterion that matches the operating information. If multiple datasets meet the selection criterion, the dataset selection unit 23 may be selected based on a pre-set priority or the dataset with the smallest maximum output value determined by the limit setting value.

[0024] In addition, the data set selection unit 23 can also be configured to select a data set based only on the operating information input by the user. The data set selection unit 23 can also be configured to display the operating information that the user can select so that the user can input the operating information. In the case of selecting the data set of Table 1, the data set selection unit 23 can be configured to request the user to select any one of the three modes of "high output", "with insulation" and "power suppression". In addition, when the insulation 17 is installed, the temperature of the heater 15 is likely to rise, and it is likely to become overheated and shorten the life. Therefore, the data set selection unit 23 is preferably configured to select the data set 1 for long life in which the limit set value is set in a manner that reduces the maximum output when the insulation 17 is installed, so as to prevent degradation caused by the heat of the heater 15.

[0025] The dataset selection unit 23 may also be configured to select a dataset based only on information indicating the state of the injection molding machine. In addition, the dataset selection unit 23 may select a dataset based not only on current operating information but also on historical records of operating information. The selection criteria for a dataset may also be, for example, the satisfaction of a certain condition for a certain period of time or longer. As a specific example, when the output of the heater 15 is above a certain value and continues to be above a certain value, the dataset 1 having a limit setting value that makes the maximum output relatively small may be selected to reduce the rate of increase of the surface temperature of the heater 15. In addition, for example, the selection criteria for a dataset may be set based on the rate of change of operating information such as the temperature rise rate of the temperature sensor 16.

[0026] The heater control unit 24 controls the output of the heater 15 to maintain the temperature of the barrel 11 at the set temperature. Furthermore, the heater control unit 24 limits the output of the heater 15 according to the data set selected by the data set selection unit 23. Specifically, the heater control unit 24 controls the input to the heater 15 so that the output of the heater 15 does not exceed the maximum output determined by the selected data set. By limiting the maximum output of the heater 15 according to the data set selected based on the operating information, the heater control unit 24 can suppress degradation of the heater 15 based on the thermal history and extend the life of the heater 15.

[0027] The data set synthesis unit 25 generates a new data set that is calculated based on the first and second data sets and selected when both the first and second selection criteria are satisfied. In the case where the limit setting value is an output rate, for example, the data set synthesis unit 25 can be configured to set the limit setting value of the new data set to the output rate calculated as the product of the output rate of the first and second data sets, or a value corresponding to the output rate. Alternatively, the data set synthesis unit 25 can set the new data set to the smaller value obtained by combining the limit setting values ​​of the first and second data sets, converted to the output of the heater 15. In this way, by providing the data set synthesis unit 25 to generate a new data set based on the first and second data sets, the maximum output of the heater 15 can be more appropriately limited according to the operating conditions. The data set synthesis unit 25 can also generate a new data set each time as needed according to the operating conditions, but it is preferable to store the generated new data set in the data set storage unit 21 for reuse.

[0028] The dataset creation unit 26 creates a new dataset based on user input. The dataset creation unit 26 can be configured to provide a user interface that displays the contents of each dataset element and allows input of values ​​for each element. By providing the dataset creation unit 26 that allows the user to create new datasets, the maximum output of the heater 15 can be optimized for various operating conditions. The new datasets created by the dataset creation unit 26 are preferably stored in the dataset storage unit 21 for reuse.

[0029] The input device 27 can be any device such as a keyboard, a mouse, a touch panel, etc. The input device 27 may be integrated with the injection molding control device 20 or connected to the injection molding control device 20 via a network.

[0030] As described above, the injection molding machine 1 equipped with the injection molding control device 20 can suppress thermal degradation of the heater 15 to achieve a longer life of the heater 15. The injection molding control device 20 has a data set selection unit 23, which selects an appropriate data set from multiple data sets including a limit setting value for limiting the maximum output of the heater 15 based on operating information.

[0031] The following supplementary notes are further disclosed regarding the above-mentioned embodiment and modification examples. (Supplementary Note 1) An injection molding control device (20) is used to control a heater (15) in an injection molding machine (10) having a barrel (11), one or more heaters (15) for heating the barrel (11), and one or more detectors (16, 18) for detecting a state value, the injection molding control device (20) comprising: a data set storage unit (21) storing a plurality of data sets each including one or more limit setting values ​​for limiting a maximum output of the heater (15); an information acquisition unit (22) acquiring operating information, the operating information being at least one of information indicating a state of the injection molding machine (10) and information input by a user; a data set selection unit (23) selecting a data set from the plurality of data sets based on the one or more operating information acquired by the information acquisition unit (22); and a heater control unit (24) controlling the output of the heater (15) according to the data set selected by the data set selection unit (23).

[0032] (Note 2) In the injection molding control device (20) of Note 1, the plurality of data sets may include one or more open-time data sets that can be selected when a heat-insulating component is not installed in the barrel (11) and one or more heat-insulating data sets that can be selected when a heat-insulating component is installed in the barrel (11), and the maximum output based on the limit setting value of the heat-insulating data set is smaller than the maximum output based on the limit setting value of the open-time data set.

[0033] (Note 3) The injection molding control device (20) of Notes 1 and 2 may also be such that the plurality of data sets include a first data set that can be selected when a first selection criterion is satisfied and a second data set that can be selected when a second selection criterion is satisfied, and the injection molding control device (20) further includes a data set synthesis unit (25) that generates a new data set that is selected when both the first selection criterion and the second selection criterion are satisfied based on the first data set and the second data set.

[0034] (Supplementary Note 4) In the injection molding control device (20) of Supplementary Note 3, the data set storage unit (21) may store the data set produced by the data set synthesis unit (25).

[0035] (Supplementary Note 5) The injection molding control device (20) of Supplementary Notes 1 to 4 may also be provided with a data set creation unit (26) that creates a new data set according to user input.

[0036] (Supplementary Note 6) In the injection molding control device (20) of Supplementary Note 5, the data set storage unit (21) may store the data set created by the data set creation unit (26).

[0037] (Supplementary Note 7) The injection molding machine (1) comprises: the injection molding control device (20) of Supplementary Notes 1 to 5; a barrel (11); one or more heaters (15) for heating the barrel (11); and one or more detectors (16, 18) for detecting status values.

[0038] The present disclosure has been described in detail above, but the present disclosure is not limited to the above-described embodiments. These embodiments can be supplemented, replaced, changed, partially deleted, etc., without departing from the scope of the present disclosure, or without departing from the scope of the present disclosure derived from the contents described in the claims and their equivalents. In addition, these embodiments can also be implemented in combination. For example, in the above-described embodiments, the order of each action and the order of each process are shown as an example and are not limited to these orders.

[0039] Description of Reference Numerals

[0040] 1 Injection molding machine 10 Molding machine body 11 Barrel 12 Screw 13 Nozzle 14 Feeder 15 Heater 16 Temperature sensor 17 Insulation 18 Mounting detector 20 Injection molding control device 21 Data set storage unit 22 Information acquisition unit 23 Data set selection unit 24 Heater control unit 25 Data set synthesis unit 26 Data set creation unit 27 Input device 111 Inner cavity 112 Main supply port 121 Motor

Claims

1. An injection molding control device for controlling a heater in an injection molding machine having a barrel, one or more heaters for heating the barrel, and one or more detectors for detecting a state value, the injection molding control device comprising: a data set storage unit storing a plurality of data sets each including one or more limit setting values ​​for limiting a maximum output of the heater; an information acquisition unit acquiring operating information, the operating information being at least one of information indicating a state of the injection molding machine and information input by a user; a data set selection unit configured to select one of the plurality of data sets based on the one or more pieces of operation information acquired by the information acquisition unit; and a heater control unit that limits the output of the heater according to the data set selected by the data set selection unit.

2. The injection molding control device according to claim 1, wherein: The multiple data sets include one or more open-time data sets that can be selected when the barrel is not equipped with a heat-insulating component and one or more heat-insulating data sets that can be selected when the barrel is equipped with a heat-insulating component, and the maximum output based on the limit setting value of the heat-insulating data set is smaller than the maximum output based on the limit setting value of the open-time data set.

3. The injection molding control device according to claim 1 or 2, wherein: The multiple data sets include a first data set that can be selected when a first selection criterion is satisfied and a second data set that can be selected when a second selection criterion is satisfied. The injection molding control device also has a data set synthesis unit, which produces a new data set based on the first data set and the second data set that is selected when the first selection criterion and the second selection criterion are simultaneously satisfied.

4. The injection molding control device according to claim 3, wherein: The dataset storage unit stores the dataset generated by the dataset synthesis unit.

5. The injection molding control device according to any one of claims 1 to 4, wherein: The system further includes a data set creating unit that creates a new data set according to a user input.

6. The injection molding control device according to claim 5, wherein: The dataset storage unit stores the dataset created by the dataset creation unit. 7 . An injection molding machine comprising: the injection molding control device according to claim 1 ; a barrel; one or more heaters for heating the barrel; and one or more detectors for detecting a state value.

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