Control device and program for injection molding machine

Abstract

Provided is a control device and program for an injection molding machine that can improve the accuracy of a calculated heat release amount of a heater. The control device for the injection molding machine includes an operation information acquisition section (12) that acquires a heater output of a heater (102) and a set temperature of the heater (102) in a prescribed period immediately before a prescribed time as operation information, a surface temperature acquisition section (15) that acquires a surface temperature of the heater (102) in the prescribed period included in the acquired operation information, a characteristic information acquisition section (21) that acquires characteristic information regarding heat release of the heater (102), an achievement information acquisition section (14) that acquires achievement of a change in a ratio of the surface temperature of the heater (102) to the set temperature with respect to a change in the heater output of the heater (102) as achievement information, an estimation section (17) that estimates the surface temperature of the heater (102) at the prescribed time based on the operation information, the achievement information, and the acquired surface temperature, and a heat release amount calculation section (22) that calculates a heat release amount from the surface of the heater (102) to the environment based on the characteristic information and the estimated surface temperature.

Description

Technical Field

[0001] The present disclosure relates to a control device and a program for an injection molding machine. Background Art

[0002] Conventionally, an injection molding machine is known that melts pellets fed into a hopper in a cylinder and then injects them into a mold. A heater is disposed on the periphery of the cylinder of the injection molding machine. The heater heats the cylinder to melt the pellets.

[0003] Monitoring the surface temperature of a heater is useful for monitoring heater status and calculating heat release. Therefore, methods such as installing temperature measurement sensors on the heater surface, measuring temperature using thermal imaging, and estimating surface temperature using equations are being implemented. Furthermore, an injection molding machine has been proposed that calculates the temperature at any location on the cylinder by taking into account the flow of heat from the heat source used to heat the cylinder (see, for example, Patent Document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2014-46488 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] When estimating surface temperature using equations, the temperatures at temperature control points and detection points obtained by additional sensors are used to estimate the temperature at arbitrary locations in the cylinder's axial and radial directions. However, in actual cylinders, sensor holes and openings exist. Therefore, the cylinder's surface temperature is not uniformly distributed. Consequently, errors may occur between the estimated temperature and the actual temperature.

[0009] Furthermore, considering the heat release of the heating source, as described in Patent Document 1, is useful for suppressing energy loss. However, Patent Document 1 assumes a uniform temperature distribution on the surface of the heating source. Therefore, errors in the heat release calculations in Patent Document 1 are likely to exist. Therefore, it would be desirable to improve the accuracy of the calculated heat release of the heater.

[0010] Solutions for solving problems

[0011] (1) The present disclosure relates to a control device for an injection molding machine, wherein the injection molding machine has a cylinder and a heater arranged around the cylinder, and the control device for the injection molding machine is used to calculate the heat release of the heater at a specified time. The control device for the injection molding machine includes: an action information acquisition unit, which acquires the heater output of the heater and the set temperature of the heater within a specified period immediately before the specified time as action information; a surface temperature acquisition unit, which acquires the surface temperature of the heater within the specified period included in the acquired action information; a characteristic information acquisition unit, which acquires characteristics related to the heat release of the heater, that is, characteristic information; an actual performance information acquisition unit, which acquires the performance of the change in the ratio of the surface temperature of the heater to the set temperature relative to the change in the heater output of the heater as performance information; an estimation unit, which estimates the surface temperature of the heater at the specified time based on the action information, the actual performance information, and the acquired surface temperature; and a heat release calculation unit, which calculates the heat release from the surface of the heater to the environment based on the characteristic information and the estimated surface temperature.

[0012] (2) In addition, the present disclosure relates to a program that causes a computer to function as a control device of an injection molding machine, wherein the injection molding machine has a cylinder and a heater arranged around the cylinder, and the control device of the injection molding machine is used to calculate the heat release of the heater at a specified time, and the program causes the computer to function as the following parts: an action information acquisition part that acquires the heater output of the heater and the set temperature of the heater within a specified period immediately before the specified time as action information; a surface temperature acquisition part that acquires the surface temperature of the heater within the specified period included in the acquired action information; a characteristic information acquisition part that acquires characteristics related to the heat release of the heater, that is, characteristic information; a performance information acquisition part that acquires the performance of the change in the ratio of the surface temperature of the heater to the set temperature relative to the change in the heater output of the heater as performance information; an estimation part that estimates the surface temperature of the heater at the specified time based on the action information, the performance information, and the acquired surface temperature; and a heat release calculation part that calculates the heat release from the surface of the heater to the environment based on the characteristic information and the estimated surface temperature.

[0013] Effects of the Invention

[0014] According to the present disclosure, it is possible to provide a control device and a program for an injection molding machine that can improve the accuracy of the calculated heat release amount of a heater. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1This is a schematic diagram showing an injection molding machine including a control device according to one embodiment of the present disclosure.

[0016] Figure 2 This is a table showing an example of performance information learned by the control device according to one embodiment.

[0017] Figure 3 This is a schematic diagram showing the relationship between the amount of heat generated and the amount of heat released by a heater of an injection molding machine including a control device according to one embodiment.

[0018] Figure 4 This is a block diagram showing the configuration of a control device according to one embodiment.

[0019] Figure 5 This is a schematic diagram showing an example of operation information of a control device according to one embodiment.

[0020] Figure 6 This is a schematic diagram showing an example of performance information of a control device according to one embodiment.

[0021] Figure 7 This is a screen diagram showing a screen displayed on a display unit of a control device according to one embodiment.

[0022] Figure 8 This is a flowchart showing the flow of operations of the control device according to one embodiment.

[0023] Figure 9 This is a screen diagram showing a screen displayed on a display unit of a control device according to a modified example.

[0024] Figure 10 This is a screen diagram showing a screen displayed on a display unit of a control device according to another modified example.

[0025] Figure 11 This is a screen diagram showing a screen displayed on a display unit of a control device according to still another modified example.

[0026] Figure 12 This is a screen diagram showing a screen displayed on a display unit of a control device according to still another modified example. DETAILED DESCRIPTION

[0027] Refer to the following Figures 1 to 8 Next, a description will be given of a control device 1 and a program of an injection molding machine 10 according to an embodiment of the present disclosure.

[0028] First, the injection molding machine 10 controlled by the control device 1 of this embodiment will be described.

[0029] The injection molding machine 10 is a device that performs molding by melting pellets and injecting them into a mold (not shown). Figure 1 As shown, the injection molding machine 10 includes, for example, a cylinder 101 , a heater 102 , and a safety cover 103 .

[0030] The cylinder 101 is, for example, a cylindrical body. One end of the cylinder 101 in the axial direction is tapered toward the end. A screw (not shown) is provided in the cylinder 101 along the axial direction. The screw stirs the melted particles while moving them toward one end of the cylinder 101.

[0031] The heaters 102 are arranged around the cylinder 101. For example, multiple heaters 102 are arranged along the axial direction of the cylinder 101. Specifically, multiple heaters 102 are arranged from the nozzle portion at the axial front end to the base end of the cylinder 101. In this embodiment, five heaters 102 are arranged along the axial direction, and each heater 102 is arranged so as to cover the outer circumference of the cylinder 101. The heaters 102 heat the cylinder 101 to, for example, 200 degrees Celsius or higher.

[0032] The safety cover 103 is a concave body arranged around the heater 102. The safety cover 103 is arranged to prevent the heater 102 from coming into contact with the heater 102 which has reached a high temperature.

[0033] According to the above injection molding machine 10, pellets are melted inside the cylinder 101 heated to above 200 degrees Celsius by the heater 102. The screw injects the melted pellets into the mold from one end of the cylinder 101. Thus, the injection molding machine 10 molds, for example, plastic products.

[0034] Here, the safety cover 103 is arranged around the heater 102, so it is difficult to directly measure the surface temperature of the heater 102 from the outside. On the other hand, it is known that there is a correlation between the actual surface temperature of the heater 102, the set temperature set for the heater 102, and the heater output of the heater 102. Specifically, it is known that there is a correlation between the ratio of the surface temperature of the heater 102 to the set temperature and the average heater output of the heater 102. For example, Figure 2 As shown, the set temperature and screw speed of heater 102 were set to: (1) 220°C, 50 rpm; (2) 180°C, 100 rpm; and (3) 180°C, 50 rpm. The results showed that the surface temperature / set temperature ratios were 1.19, 0.792, and 0.919, respectively, and the average heater outputs were 46.6%, 6.62%, and 14.5%, respectively. The correlation coefficient between the surface temperature / set temperature ratio and the heater output was 0.991. Therefore, it can be seen that there is a strong correlation between the surface temperature / set temperature ratio and the heater output.

[0035] In addition, if Figure 3 As shown, the heat generation E of the heater 102 Hi Able to release heat E through convectionCi , radiant heat E Ri , heat taken away by cooling water E W , heat transferred to the machine body (hopper side) E0, heat received by the resin E M , and shear energy E S Here, i (i=1, 2, ..., k) is a natural number and represents a number for identifying k heaters 102. For example, the amount of heat released to the air (convection heat release + radiation heat release) can be expressed by the following number 1.

[0036] [Number 1]

[0037]

[0038] The control device 1 of the injection molding machine 10 according to the following embodiment uses the above-mentioned correlation to estimate the surface temperature of the heater 102 from the outside. As a result, the control device 1 of the injection molding machine 10 according to the following embodiment can estimate the surface temperature of the heater 102 with higher accuracy compared to the case where the surface temperature of the heater 102 is estimated based on the temperature control point and the detection point such as the additional sensor using an equation. In addition, the control device 1 of the injection molding machine 10 according to the following embodiment improves the accuracy of the estimated heat release amount by calculating the heat release amount based on the surface temperature of the heater 102. In addition, in the following embodiment, "in operation" refers to the moment when the injection molding machine 10 is currently operating. In addition, in the following embodiment, "predetermined time" refers to the moment when the surface temperature of the heater 102 is estimated.

[0039] Next, refer to Figures 1 to 8 A control device 1 of an injection molding machine 10 according to an embodiment of the present disclosure will be described.

[0040] The control device 1 is a device for controlling the injection molding machine 10. Specifically, the control device 1 is a device for controlling the molding conditions of the injection molding machine 10. Figure 1 As shown, the control device 1 is connected to the injection molding machine 10, for example. The control device 1 specifies and controls the molding conditions such as the injection molding speed, pressure, temperature of the cylinder 101, mold temperature, and injection amount of the melted pellets. The control device 1 in this embodiment is a device that calculates the heat release of the heater 102 at a specified time. Figure 4 As shown, the control device 1 includes an action information storage unit 11, an action information acquisition unit 12, a characteristic information storage unit 20, a characteristic information acquisition unit 21, a performance information storage unit 13, a performance information acquisition unit 14, a surface temperature acquisition unit 15, a shift calculation unit 16, an estimation unit 17, a heat release calculation unit 22, an output unit 18, and an output control unit 19.

[0041] The action information storage unit 11 is, for example, a storage medium such as a hard disk. The action information storage unit 11 stores action information related to the set temperature of the heater 102 of the injection molding machine 10 and the heater output of the heater 102 in operation. In addition, the action information storage unit 11 stores, for example, the content of instructions related to the action of the injection molding machine 10 as action information. The action information storage unit 11 stores, for example, the above-mentioned molding conditions as action information. Figure 5 As shown, the operation information storage unit 11 sets the start time of operation to 0 and the predetermined time to T. It then stores heater outputs y_0, y_1, ..., y_T-1 at each sampling period t_1 (s) until t_T-1 immediately before the predetermined time. Furthermore, the operation information storage unit 11 stores S (°C) as the set temperature.

[0042] The motion information acquisition unit 12 is implemented, for example, by a CPU. The motion information acquisition unit 12 acquires the heater output of the heater 102 and the set temperature of the heater 102 during a predetermined period immediately before a predetermined time as motion information. In this embodiment, the motion information acquisition unit 12 acquires motion information from the motion information storage unit 11. For example, the motion information acquisition unit 12 acquires the heater output of the heater 102 and the set temperature of the heater 102 during the period from the start of operation of the injection molding machine 10 to immediately before the predetermined time as motion information. For example, the motion information acquisition unit 12 acquires the heater output represented by a predetermined sampling period until immediately before the predetermined time.

[0043] The characteristic information storage unit 20 is, for example, a storage medium such as a hard disk. The characteristic information storage unit 20 stores characteristic information related to the heat dissipation of the heater 102. The characteristic information storage unit 20 stores information unique to the heater 102 as characteristic information. For example, the characteristic information storage unit 20 stores the surface area, emissivity, and Stefan-Boltzmann coefficient of the heater 102 as characteristic information.

[0044] The characteristic information acquisition unit 21 is realized by, for example, the operation of a CPU. The characteristic information acquisition unit 21 acquires characteristic information of the heater 102 including the surface area of ​​the heater 102 .

[0045] The performance information storage unit 13 is, for example, a storage medium such as a hard disk. The performance information storage unit 13 stores the performance of the transition of the ratio of the surface temperature of the heater 102 to the set temperature relative to the transition of the heater output of the heater 102 as performance information. The performance information storage unit 13 stores, for example, the transition of the heater output of the heater 102 measured in advance as input data, and stores the transition of the ratio of the surface temperature of the heater 102 to the set temperature of the heater 102 (surface temperature / set temperature) measured at the same time as performance information. The performance information storage unit 13 stores performance information obtained in advance by learning teaching data with the heater output as input. The performance information storage unit 13 can, for example, store in advance performance information obtained by using a temperature sensor (not shown) in contact with the surface of the heater 102 and by learning the performance information. Figure 2 The performance information storage unit 13 stores, for example, a plurality of performances as performance information. Figure 6 As shown, the performance information storage unit 13 sets the measurement number to M (M is a natural number), the measurement start time (action start time) to 0, and the time when the heater output is obtained to t_N (N is a natural number) for each measured result, and saves the performance information with the value of the heater output as x_MN and the value of the surface temperature / set temperature as R_MN.

[0046] The performance information acquisition unit 14 is implemented, for example, by a CPU. The performance information acquisition unit 14 acquires performance information from the performance information storage unit 13. For example, the performance information acquisition unit 14 acquires, as performance information, the performance of the ratio of the surface temperature of heater 102 to the set temperature relative to the change in heater output of heater 102. Specifically, the performance information acquisition unit 14 acquires, for each past heater output, the ratio of the past set temperature to the past surface temperature (surface temperature / set temperature) as performance information.

[0047] The surface temperature acquisition unit 15 is implemented, for example, by a CPU. The surface temperature acquisition unit 15 acquires the surface temperature of the heater 102 during the period included in the acquired operation information. For example, the surface temperature acquisition unit 15 acquires the surface temperature estimated by the estimation unit 17 (described later) during the period included in the acquired operation information. Alternatively, the surface temperature acquisition unit 15 acquires the surface temperature actually measured or provided externally, instead of the estimated surface temperature. For example, the surface temperature acquisition unit 15 acquires the surface temperature TP_A (°C) every sampling period t_1 (A = 1, 2, ..., t-1).

[0048] The transition calculation unit 16 is implemented, for example, by a CPU. Based on the acquired operation information and the acquired surface temperature, the transition calculation unit 16 calculates the transition of the ratio of the surface temperature to the set temperature relative to the transition of the heater output included in the operation information. For example, the transition calculation unit 16 calculates the value of surface temperature / set temperature for each heater output included in the operation information. In this embodiment, the transition calculation unit 16 calculates (TP_A / S) (A = 1, 2, ... t-1) every sampling period t_1.

[0049] Estimation unit 17 is implemented, for example, by a CPU. Estimation unit 17 estimates the surface temperature of heater 102 at a predetermined time based on the operation information, performance information, and the acquired surface temperature. Specifically, estimation unit 17 estimates the surface temperature at the predetermined time using performance data included in the performance information that is similar or consistent with the operation information and the calculated ratio. Estimation unit 17 estimates the surface temperature at the predetermined time based on the ratio of the set temperature to the surface temperature at the time corresponding to the predetermined time, as indicated by the performance data that is similar or consistent with the transition of the heater output and the ratio of the set temperature to the surface temperature included in the operation information within a predetermined period immediately before the predetermined time. Estimation unit 17 then acquires the ratio of the set temperature to the surface temperature at the next time (corresponding to the predetermined time) after the similar or consistent period, as included in the identified performance data. Estimation unit 17 then estimates the surface temperature at the predetermined time by multiplying the acquired ratio by the set temperature included in the operation information.

[0050] The heat release calculation unit 22 is implemented by, for example, a CPU. The heat release calculation unit 22 calculates the amount of heat released from the surface of the heater 102 to the environment based on the characteristic information and the estimated surface temperature. In other words, the heat release calculation unit 22 calculates the sum of the convective heat release and the radiant heat release of the k heaters 102 as the amount of heat released to the air. Here, the heat release calculation unit 22 assumes that the heat release (J) from the heater 102 to the environment is E Ai , let the convection heat release (J) be E Ci , let the radiation heat (J) be E Ri , the surface temperature (K) of the heater 102 is set to T H , the surface area of ​​the heater 102 (m 2 ) is set to A i 、The thermal conductivity (W / m 2 K) is h, emissivity is ε, and the Stefan-Boltzmann coefficient (W / m 2 K 4) is set as σ, the numbers used to identify k heaters 102 are set as i=1, 2...k, and the heat release E is calculated using the following number 2 Ai .

[0051] [Number 2]

[0052] E Ai =E Ci +E Ri

[0053]

[0054]

[0055] Alternatively, the heat release calculation unit 22 may calculate E using the thermal conductivity h as a function of the temperature difference between the surface temperature of the heater 102 and the ambient temperature. Ci .

[0056] The output unit 18 is a display unit such as a display. The output unit 18 outputs the calculated heat release to the outside. Figure 7 As shown, the output unit 18 displays, for example, the position of the heater 102 relative to the cylinder 101 , the set temperature, the heater output, and the amount of heat released.

[0057] The output control unit 19 is realized by, for example, the operation of a CPU, and causes the output unit 18 to output the calculated heat release amount.

[0058] Next, refer to Figure 8 Next, the flow of processing performed by the control device 1 will be described.

[0059] First, the performance information acquisition unit 14 acquires performance information (step S1 ). The performance information acquisition unit 14 acquires a plurality of performance information from the performance information storage unit 13 , for example.

[0060] Next, the characteristic information acquisition unit 21 acquires characteristic information (step S2). The characteristic information acquisition unit 21 acquires characteristic information stored in the characteristic information storage unit 20 in advance, for example.

[0061] Next, the motion information acquisition unit 12 acquires motion information (step S3). The motion information acquisition unit 12 acquires motion information stored in advance in the motion information storage unit 11, for example.

[0062] Next, the surface temperature acquisition unit 15 acquires the surface temperature corresponding to the operation information (step S4 ).

[0063] Next, the transition calculation unit 16 calculates the transition of the ratio of the surface temperature to the set temperature relative to the transition of the heater output included in the operation information based on the acquired operation information and the acquired surface temperature (step S5). Next, the estimation unit 17 estimates the surface temperature of the heater 102 based on the operation information, the surface temperature, and the performance information (step S6).

[0064] In step S7, the heat release calculation unit 22 calculates the heat release amount based on the characteristic information and the estimated surface temperature of the heater 102. The heat release calculation unit 22 calculates the heat release amount for each heater 102, for example.

[0065] In step S8, the output control unit 19 outputs the calculated heat release amount to the output unit 18. The output unit 18 displays the calculated heat release amount, for example.

[0066] Next, it is determined whether the calculation of the heat release is repeated (step S9). If the calculation is repeated (step S9: "Yes"), the process returns to step S3. On the other hand, if the calculation is completed (step S9: "No"), the process of this flow ends.

[0067] Next, the procedure of this embodiment will be described.

[0068] Each component included in the control device 1 of the injection molding machine 10 can be realized by hardware, software, or a combination thereof. Here, realization by software means that the control device 1 is realized by a computer reading and executing a program.

[0069] The program can be stored and supplied to the computer using various types of non-transitory computer readable media. Non-transitory computer readable media include various types of tangible recording media (tangible storage media). Examples of non-transitory computer readable media include magnetic recording media (such as floppy disks, magnetic tapes, hard disk drives), optical magnetic recording media (such as optical magnetic disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / Ws, semiconductor memories (such as mask ROMs, PROMs (Programmable ROMs), EPROMs (Erasable PROMs), flash ROMs, and RAMs (random access memory). In addition, the program can also be supplied to the computer via various types of transitory computer readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. Transitory computer readable media can supply the program to the computer via wired communication paths such as electric wires and optical fibers, or wireless communication paths.

[0070] As described above, the control device 1 and the program according to one embodiment can provide the following effects.

[0071] (1) An injection molding machine 10 includes a cylinder 101 and a heater 102 disposed around the cylinder 101. A control device 1 of the injection molding machine 10 is configured to calculate the amount of heat released by the heater 102 at a predetermined time. The control device 1 of the injection molding machine 10 includes: an operation information acquisition unit 12 for acquiring, as operation information, the heater output of the heater 102 and the set temperature of the heater 102 within a predetermined period immediately before the predetermined time; and a surface temperature acquisition unit 15 for acquiring the surface temperature of the heater 102 within the predetermined period included in the acquired operation information. A characteristic information acquisition unit 21 acquires characteristics related to heat release of the heater 102, i.e., characteristic information; a performance information acquisition unit 14 acquires the performance of the change in the ratio of the surface temperature of the heater 102 to the set temperature relative to the change in the heater output of the heater 102 as performance information; an estimation unit 17 estimates the surface temperature of the heater 102 at a specified time based on the action information, the performance information, and the acquired surface temperature; and a heat release calculation unit 22 calculates the amount of heat released from the surface of the heater 102 to the environment based on the characteristic information and the estimated surface temperature.

[0072] In addition, the program causes the computer to function as a control device 1 of an injection molding machine 10, the injection molding machine 10 having a cylinder 101 and a heater 102 arranged around the cylinder 101. The control device 1 of the injection molding machine 10 is used to calculate the amount of heat released by the heater 102 at a predetermined time. The program causes the computer to function as the following units: an operation information acquisition unit 12 that acquires the heater output of the heater 102 and the set temperature of the heater 102 within a predetermined period immediately before the predetermined time as operation information; a surface temperature acquisition unit 15 that acquires the surface temperature of the surface ... the surface temperature of the heater 102; a characteristic information acquisition unit 21, which acquires characteristics related to the heat release of the heater 102, that is, characteristic information; a performance information acquisition unit 14, which acquires the performance of the change in the ratio of the surface temperature of the heater 102 to the set temperature relative to the change in the heater output of the heater 102 as performance information; an estimation unit 17, which estimates the surface temperature of the heater 102 at a specified time based on the action information, the performance information, and the acquired surface temperature; and a heat release calculation unit 22, which calculates the amount of heat released from the surface of the heater 102 to the environment based on the characteristic information and the estimated surface temperature.

[0073] As a result, the accuracy of the estimated surface temperature of the heater 102 can be improved regardless of the shape (concavity) around the cylinder body 101. In addition, there is no need to set a physical sensor or the like on the surface of the heater 102, so the cost can be suppressed. Moreover, the heat release of each heater 102 can be calculated based on the estimated surface temperature. Therefore, the heat release from the surface of the heater 102 to the air can be calculated with further high accuracy. As a result, by setting the operating and molding conditions that minimize the heat release, the life of the heater can be extended and the driving power of the injection molding machine 10 can be suppressed.

[0074] (2) The control device 1 of the injection molding machine 10 further includes a transition calculation unit 16. The transition calculation unit 16 calculates the transition of the ratio of the surface temperature to the set temperature relative to the transition of the heater output included in the action information based on the acquired action information and the acquired surface temperature. The estimation unit 17 estimates the surface temperature at a predetermined time using the results included in the performance information that are similar to or consistent with the action information and the calculated transition of the ratio. In this way, the surface temperature can be easily estimated by acquiring the heater output and the set temperature.

[0075] (3) The surface temperature acquisition unit 15 acquires the surface temperature of the heater 102 as a ratio of the surface temperature of the heater 102 to the set temperature. The estimation unit 17 estimates the surface temperature at a predetermined time using the performance information included in the performance information that is similar to or consistent with the operation information and the change in the acquired ratio. Thus, the surface temperature can be easily estimated by directly acquiring the ratio of the set temperature to the surface temperature.

[0076] (4) The heat release calculation unit 22 calculates the heat release using the parameters calculated based on the surface temperature as part of the characteristic information. This makes it possible to further improve the accuracy of the calculated heat release by using the estimated surface temperature.

[0077] While preferred embodiments of the control device and program for the injection molding machine of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments and can be modified as appropriate.

[0078] For example, in the above embodiment, the performance information acquisition unit 14 may acquire performance information at multiple points on the surface of one heater 102. Thus, the estimation unit 17 may estimate the surface temperature at multiple points on the surface of one heater 102. Then, the heat release calculation unit 22 may calculate the heat release at multiple points on the surface of one heater 102. In this case, the heat release calculation unit 22 may calculate the convection heat release E. Ci and radiation heat E Ri , the surface temperature (K) of the heater 102 at each measurement point is set to T Hm , the occupied area (m 2 ) is set to A im , let the number representing each measurement point be m = 1, 2, ..., and calculate the heat release by calculating the following number 3.

[0079] [Number 3]

[0080]

[0081]

[0082] In addition, in the above embodiment, if Figure 9 As shown in FIG. 1 , the output control unit 19 may also cause the output unit 18 to display the heat release amount in the form of a bar graph for each heater 102. Figure 10 As shown, the output control unit 19 may also cause the output unit 18 to separately display the convective heat release and the radiant heat release. This makes it possible to easily grasp the difference in heat release between the heaters 102.

[0083] In addition, in the above embodiment, if Figure 11As shown, the output control unit 19 may cause the output unit 18 to display a scatter diagram summarizing the heat release amount at each predetermined time. This allows the heat release amount of the heater 102 to be displayed in time series, making it easy to monitor abnormal heat release amount of the heater 102.

[0084] In addition, in the above embodiment, if Figure 12 As shown, the output control unit 19 may cause the output unit 18 to display, at each predetermined time, a list of the heat release amounts of the heaters 102. For example, the output control unit 19 may cause the output unit 18 to display, for each heater 102, the maximum value, minimum value, average value, difference between the maximum value and the minimum value, and standard deviation.

[0085] In the above embodiment, the action information acquisition unit 12 acquires action information after the performance information acquisition unit 14 acquires performance information. However, the present invention is not limited thereto and the action information acquisition unit 12 may acquire action information before the performance information acquisition unit 14 acquires performance information.

[0086] In the above embodiment, the injection molding machine 10 may be either a coaxial reciprocating screw type or a plunger type. Furthermore, in the above embodiment, the surface temperature of the heater 102 included in the performance information may be measured directly by a temperature sensor (not shown) or indirectly by a thermal imager (radiation thermometer, not shown).

[0087] In the above embodiment, the output unit 18 may be configured independently of the control device 1 (injection molding machine 10). Furthermore, the control device 1 may manage multiple injection molding machines 10. Furthermore, in the above embodiment, the output control unit 19 may cause the output unit 18 to display the surface temperature of the heater 102 in addition to the heat release amount.

[0088] In the above embodiment, the heat release calculation unit 22 may calculate the heat release amount per unit time or per cycle time, or a predetermined time period. In the above embodiment, the heat release calculation unit 22 may calculate the total heat release amount or the heat release amount per unit time period for a predetermined time period. In addition, the heat release calculation unit 22 may calculate the average heat release amount per fixed time period or the heat release amount at a specific time period.

[0089] In the above embodiment, the operation information acquisition unit 12 may use the detected temperature (or estimated surface temperature) detected at the temperature control point instead of the set temperature. In the above embodiment, the estimation unit 17 may estimate the surface temperature of the heater 102 by setting the surface temperature of the heater 102 at the start of operation of the injection molding machine 10 to E% (E is an arbitrary constant or variable) of the detected temperature at the control point of the heater 102. For example, the estimation unit may estimate the surface temperature by setting the variable E = 95 when the detected temperature is below 50 degrees Celsius and E = 90 when the detected temperature is above 50 degrees Celsius.

[0090] In the above embodiment, the predetermined time is not limited to the current time, but may be a time in the past or future. If the predetermined time is in the past, the operation information acquisition unit 12 acquires the heater output and setting information for the predetermined period immediately before the predetermined time. If the predetermined time is in the future, the operation information acquisition unit 12 acquires the estimated heater output and setting information for the predetermined period immediately before the predetermined time.

[0091] In the above embodiment, the surface temperature acquisition unit 15 may acquire the ratio of the set temperature to the surface temperature instead of the surface temperature. In this case, the control device 1 may not include the shift calculation unit 16.

[0092] Description of Reference Numerals

[0093] 1: Control device; 10: Injection molding machine; 12: Action information acquisition unit; 14: Performance information acquisition unit; 16: Transition calculation unit; 17: Estimation unit; 21: Characteristics information acquisition unit; 22: Heat release calculation unit; 101: Cylinder; 102: Heater.

Claims

1. A control device for an injection molding machine, the injection molding machine comprising a cylinder and a heater disposed around the cylinder, the control device for the injection molding machine being configured to calculate a heat release amount of the heater at a predetermined time, the control device comprising: an operation information acquisition unit that acquires, as operation information, a heater output of the heater and a set temperature of the heater within a predetermined period immediately before the predetermined time; a surface temperature acquisition unit that acquires a surface temperature of the heater within a predetermined period included in the acquired operation information; a characteristic information acquisition unit that acquires characteristic information related to heat release of the heater; a performance information acquisition unit that acquires, as performance information, a performance of a change in a ratio of a surface temperature of the heater to a set temperature relative to a change in a heater output of the heater; an estimating unit that estimates, based on the performance information and from the transition of the heater output in the operation information, a ratio of the surface temperature to the set temperature at the predetermined time, and calculates an estimated value of the surface temperature of the heater at the predetermined time by multiplying the estimated ratio of the surface temperature to the set temperature by the set temperature of the heater at the predetermined time in the operation information; as well as A heat release calculation unit calculates a heat release amount from the surface of the heater to the environment based on the characteristic information and the estimated surface temperature.

2. The control device for an injection molding machine according to claim 1, wherein: further comprising a transition calculation unit that calculates, based on the acquired operation information and the acquired surface temperature, a transition of the ratio of the surface temperature to the set temperature relative to a transition of the heater output included in the operation information, The estimation unit estimates the surface temperature at the predetermined time using, among the performance information included in the performance information, performance that matches the operation information and the transition of the ratio calculated by the transition calculation unit.

3. The control device for an injection molding machine according to claim 1, wherein: The surface temperature acquisition unit acquires the surface temperature of the heater as a ratio of the surface temperature of the heater to a set temperature. The estimation unit estimates the surface temperature at the predetermined time using, among the performance information included in the performance information, performance that matches the operation information and the transition of the ratio acquired by the performance information acquisition unit.

4. The control device for an injection molding machine according to claim 2, wherein: The estimation unit estimates the surface temperature at the predetermined time based on the ratio of the surface temperature at the predetermined time corresponding to the predetermined time and the set temperature, as indicated by actual results consistent with the transition of the ratio calculated by the transition calculation unit.

5. The control device for an injection molding machine according to claim 3, wherein: The estimation unit estimates the surface temperature at the predetermined time based on a ratio of the surface temperature at a time corresponding to the predetermined time, which is indicated by actual results consistent with a change in the ratio acquired by the actual results information acquisition unit, to a set temperature.

6. The control device for an injection molding machine according to any one of claims 1 to 5, wherein: The heat release calculation unit calculates the heat release amount by using a parameter calculated based on the surface temperature for a part of the characteristic information.

7. A computer-readable medium, a non-transitory computer-readable medium storing a program, the program causing a computer to function as a control device for an injection molding machine, the injection molding machine comprising a cylinder and a heater disposed around the cylinder, the control device for the injection molding machine being configured to calculate a heat release amount of the heater at a predetermined time, the program causing the computer to function as the following units: an operation information acquisition unit that acquires, as operation information, a heater output of the heater and a set temperature of the heater within a predetermined period immediately before the predetermined time; a surface temperature acquisition unit that acquires a surface temperature of the heater within a predetermined period included in the acquired operation information; a characteristic information acquisition unit that acquires characteristic information related to heat release of the heater; a performance information acquisition unit that acquires, as performance information, a performance of a change in a ratio of a surface temperature of the heater to a set temperature relative to a change in a heater output of the heater; an estimating unit that estimates, based on the performance information and from the transition of the heater output in the operation information, a ratio of the surface temperature to the set temperature at the predetermined time, and calculates an estimated value of the surface temperature of the heater at the predetermined time by multiplying the estimated ratio of the surface temperature to the set temperature by the set temperature of the heater at the predetermined time in the operation information; as well as A heat release calculation unit calculates a heat release amount from the surface of the heater to the environment based on the characteristic information and the estimated surface temperature.

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