Control device and program for injection molding machine

Abstract

The invention provides a technology capable of mastering the plasticization state in a cylinder in detail in an injection molding machine provided with a plurality of heaters. A control device (10) of an injection molding machine (1) is provided with: an operation information acquisition unit (11) that acquires operation information relating to the operation of heaters (24a-24d) and a screw (23); a characteristic information acquisition unit (12) that acquires characteristic information relating to characteristics of the injection molding machine (1); a calculation unit (15) that, on the basis of the acquired operation information and characteristic information, calculates the amount of heat transfer (ETi) from the heaters (24a-24d) to the molding material for each of the areas of the plurality of heaters (24a-24d) divided in the axial direction, and calculates the amount of shear heat (ES) received by the molding material due to the operation of the screw (23); and an output unit (20) that executes a process for displaying the heat transfer amount (ETi) and the shear heat generation amount (ES) on a display device (6) in such a manner that the heat transfer amount (ETi) and the shear heat generation amount (ES) are distinguished by each of a plurality of regions divided in the axial direction as the calculation results of the calculation unit (15).

Description

Technical Field

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

[0002] Injection molding machines are known that melt pellets placed in a hopper within a barrel and inject them into a mold. A heater is placed around the outer periphery of the barrel of the injection molding machine. The heater heats the barrel, melting the pellets (molding material). Furthermore, the molding material is mixed and plasticized by rotating a screw within the barrel. In this way, the molding material is plasticized by heat transfer from the heater and shear heat generated by the shear action of the screw's rotation.

[0003] In this type of injection molding machine, the following technology is known (for example, refer to Patent Document 1): estimating the heater surface temperature based on the set temperature and operating rate of the heater, calculating the heater heat transfer amount transferred from the heater to the material and the shear heat generation based on the screw, and displaying them in the form of numerical values, pie charts, bar charts, etc.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2021 / 246524 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] The technology described in Patent Document 1 can determine the relationship between the amount of heat transferred by a heater and the amount of shear heat generated. However, while this display can reveal the proportion of heat transfer and shear energy in the total energy received by the molding material during the plasticization process, it is difficult to determine the relationship between heat transfer and shear energy for each heater when multiple heaters are used for heating. This existing technology leaves room for improvement in terms of providing a more detailed understanding of the plasticization state within the barrel.

[0009] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a technology capable of grasping the plasticization state inside a cylinder in detail in an injection molding machine equipped with a plurality of heaters.

[0010] Solutions for solving problems

[0011] The present invention discloses a control device for an injection molding machine, wherein the injection molding machine includes a barrel, a plurality of heaters axially arranged on the barrel, and a screw arranged inside the barrel, the control device for the injection molding machine includes: an action information acquisition unit, which acquires action information related to the actions of the heater and the screw; a characteristic information acquisition unit, which acquires characteristic information related to the characteristics of the injection molding machine; a calculation unit, which calculates the amount of heat transferred from the heater to the molding material for each of the plurality of heater areas divided along the axial direction based on the acquired action information and the characteristic information, and calculates the amount of shear heat generated by the molding material due to the action of the screw; and an output unit, which performs processing to display the heat transfer and the shear heat generated as calculation results of the calculation unit on a display device in a manner differentiated according to each of the plurality of areas divided along the axial direction.

[0012] In addition, the present disclosure is a program that enables a computer that controls an injection molding machine having a barrel, multiple heaters arranged axially on the barrel, and a screw arranged inside the barrel to perform the following functions: an action information acquisition function for acquiring action information related to the action of the heater and the screw; a characteristic information acquisition function for acquiring characteristic information related to the characteristics of the injection molding machine; an operation function for calculating the amount of heat transferred from the heater to the molding material for each of the multiple heater areas divided along the axial direction based on the acquired action information and the characteristic information, and calculating the amount of shear heat generated by the molding material due to the action of the screw; and an output function for performing processing to display the amount of heat transferred together with the shear heat generated as the operation results of the operation function on a display device in a manner that is distinguished for each of the multiple areas divided along the axial direction.

[0013] Effects of the Invention

[0014] According to the present disclosure, it is possible to provide a technology capable of grasping the plasticization state inside a cylinder in detail in an injection molding machine equipped with a plurality of heaters. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram showing the structure of the injection molding machine according to the first embodiment.

[0016] Figure 2 It is a perspective view showing a heater disposed in the cylinder according to the first embodiment.

[0017] Figure 3 This is a functional block diagram of the control device for the injection molding machine according to the first embodiment.

[0018] Figure 4This is a schematic diagram illustrating the thermal balance during molding execution.

[0019] Figure 5 This is a schematic diagram illustrating the thermal balance when molding is stopped.

[0020] Figure 6 This is a diagram showing an example of the energy flow inside the cylinder displayed on the display device by the output unit of the first embodiment.

[0021] Figure 7 This is a diagram showing an example of a table displayed on the display device by the output unit according to the first embodiment.

[0022] Figure 8 This is a diagram showing an example of a bar graph displayed on a display device by the output unit according to the first embodiment.

[0023] Figure 9 This is a diagram showing an example of a pie chart displayed on the display device by the output unit according to the first embodiment.

[0024] Figure 10 This is a diagram showing an example of the energy flow inside the cylinder and the calculation results displayed on the display device by the output unit of the first embodiment.

[0025] Figure 11 This is a flowchart showing an example of the flow of display processing by the control device of the injection molding machine according to the first embodiment.

[0026] Figure 12 This is a diagram showing an example of the energy flow inside the cylinder displayed on the display device by the output unit according to the second embodiment.

[0027] Figure 13 This is a diagram illustrating heat balance taking heat dissipation into consideration.

[0028] Figure 14 This is a diagram showing an example of the energy flow inside the cylinder displayed on the display device by the output unit according to the third embodiment.

[0029] Figure 15 This is a diagram showing an example of the energy flow inside the cylinder and the calculation results displayed on the display device by the output unit of the fourth embodiment.

[0030] Figure 16 This is a diagram showing an example of a table displayed on a display device by an output unit according to the fourth embodiment.

[0031] Figure 17 This is a diagram showing an example of a bar graph displayed on a display device by the output unit according to the fourth embodiment.

[0032] Figure 18 This is a table showing conditions of a calculation example of the control device of this embodiment.

[0033] Figure 19 It is a bar graph showing the calculation results of the control device of this embodiment. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the description of the second embodiment and thereafter, the same reference numerals are given to the same components as those of the first embodiment, and their descriptions are omitted as appropriate.

[0035] [First embodiment]

[0036] Figure 1 It is a schematic diagram showing the structure of the injection molding machine 1 according to the first embodiment. Figure 2 This is a perspective view showing heaters 24a to 24d disposed in the cylinder 22 of the injection molding machine 1 according to the first embodiment. The injection molding machine 1 of this embodiment includes an injection unit 2 , a mold clamping unit 3 , a control device 10 , and a display device 6 .

[0037] The injection unit 2 is an injection device comprising a hopper 21, a barrel 22, a screw 23, and a cooling jacket 26. The barrel 22 is, for example, cylindrical. Resin stored in the hopper 21 is supplied to the barrel 22. The screw 23 is disposed within the barrel 22 and rotates to convey the resin toward the front end of the barrel 22. A screw head 30 is disposed at the front end of the screw 23 to prevent backflow during injection. The cooling jacket 26 cools the interior of the barrel 22 (for example, the base portion of the barrel 22). Cooling water circulates through the cooling jacket 26.

[0038] like Figure 2 As shown, the plurality of heaters 24a to 24d are arranged, for example, along the axial direction of the barrel 22. Specifically, the plurality of heaters 24a to 24d are arranged in a region from the nozzle portion 25 at the axial front end of the barrel 22 to the base end.

[0039] In the present embodiment, four heaters 24a to 24d are arranged along the axial direction in a manner covering the outer periphery of the barrel 22. Heater 24a is one of the front end side heaters arranged at the nozzle portion 25. Heaters 24b to 24d are located upstream of the nozzle portion 25 in the conveying direction of the particles. Heater 24b is one of the front end side heaters located closest to the nozzle portion 25 and is located in the metering portion. Heater 24c is located between heater 24b and heater 24d and is located in the compression portion inside the barrel 22. Heater 24d is located at the position farthest from the nozzle portion 25 and is located in the supply portion inside the barrel 22. In addition, the number and position of heaters 24a to 24d are not limited to the structure of the present embodiment.

[0040] The pellets are melted by heating the cylinder 22 with the heaters 24 a to 24 d . The melted pellets are conveyed toward the nozzle 25 by the screw 23 and injected into the mold 5 .

[0041] The mold clamping unit 3 is a device for clamping the mold 5. By clamping the mold 5 by the mold clamping unit 3, a molded product is molded.

[0042] Next, the control device 10 will be described. The control device 10 of the injection molding machine 1 according to the first embodiment is configured using, for example, a computer comprising memory such as ROM (read only memory) and RAM (random access memory), a CPU (control processing unit), and a communication control unit interconnected via a bus. The functions and operations of the various functional units of the control device 10, described below, are implemented through the cooperation of the CPU, memory, and control programs stored in the memory, mounted on the computer.

[0043] The display device 6 is, for example, an output device such as a liquid crystal display or a touch panel display.

[0044] Next, refer to Figure 3 The functions of the control device 10 will be described. Figure 3 This is a functional block diagram of the control device 10 of the injection molding machine 1 according to the first embodiment. The control device 10 includes a motion information acquisition unit 11 (motion information acquisition function), a characteristic information acquisition unit 12 (characteristic information acquisition function), a calculation unit 15 (calculation function), and an output unit 20 (output function) as functional units, which are executed by a CPU.

[0045] The operation information acquisition unit 11 acquires operation information related to the operation of the heaters 24a-24d. In this embodiment, the operation information related to the heaters 24a-24d is the operating rate of each heater 24a-24d. The operating rate is, for example, an indicator of the operating status expressed as 0-100%. The operating rate is determined based on, for example, the output of the heaters 24a-24d, such as the voltage.

[0046] Furthermore, the motion information acquiring unit 11 acquires, as motion information, information related to the motion of the screw 23. The information related to the motion of the screw 23 includes, for example, the motor current during measurement and the rotational angular velocity of the screw 23.

[0047] The characteristic information acquisition unit 12 acquires characteristic information indicating the characteristics of the injection molding machine 1. The characteristic information is, for example, the capacity of the heaters 24a to 24d. The capacity of the heaters 24a to 24d mentioned here is a rated capacity of 1500W at 200V.

[0048] The characteristic information acquisition unit 12 also acquires, as characteristic information, information related to the characteristics of the screw 23. Examples of the information related to the characteristics of the screw 23 include a reduction ratio between the screw 23 and a motor that rotates the screw 23, mechanical efficiency, and a torque constant of the motor that rotates the screw 23.

[0049] The calculation unit 15 calculates the calorific value, heat transfer value, and shear heat value of the heaters 24 a to 24 d based on the acquired operation information and characteristic information.

[0050] The calculation of the heat amount by the calculation unit 15 will be described. For example, the calculation unit 15 calculates the heat amount generated by each of the heaters 24a to 24d within a predetermined time while the cylinder 22 is maintained at a preset temperature.

[0051] An example of a method for calculating the calorific value by the calculation unit 15 is described. The calorific value can be calculated by, for example, the following formula (1). Hi Indicates the heat output, t1 indicates the calculation start time, t2 indicates the calculation end time, W i Indicates the heater capacity, r i Indicates the heater operation rate. i includes a number (i=0, 1, 2, 3) for identifying heaters 24a to 24d.

[0052] [Number 1]

[0053]

[0054] In addition, the heater rated capacity indicates a specific voltage V R (For example, 220V) power consumption. However, the voltage supplied to the injection molding machine 1 may actually be different from the specified voltage. Therefore, as shown in the following formula (2), the calculation unit 15 may also calculate the power consumption of the heater 24a~24d based on the rated voltage V R The calorific value is calculated by correcting the value of the actual power supply voltage V of the injection molding machine 1 .

[0055] [Number 2]

[0056]

[0057] The calculation of the heat transfer amount by the calculation unit 15 is described. The calculation unit 15 calculates the heat transfer amount from each heater 24a to 24d to the resin based on the calculated heat generation amount. An example of the method of calculating the heat transfer amount by the calculation unit 15 is described. The heat transfer amount from the heaters 24a to 24d to the resin is represented by E Ti When the cylinder 22 is maintained at a predetermined set temperature, the heat generated during molding is set to E Hi , the heat generated when molding is stopped is set as E' Hi, the heat transfer becomes the relationship of the following formula (3). As shown in the following formula (3), the heat generated during molding can be calculated based on the heat generated during molding. Hi The heat generated when molding stops E' Hi The difference is used to calculate the heat transfer E Ti In addition, the calculated heat transfer E Ti When the value is negative, heat is not transferred from the heaters 24 a to 24 d to the resin. Therefore, the heat transfer amount is set to 0 in this case.

[0058] [Number 3]

[0059]

[0060] Reference Figure 4 and Figure 5 Explain formula (3). Figure 4 and Figure 5 In the description, heater 24b (i=1) is taken as an example.

[0061] Figure 4 This is a schematic diagram illustrating the thermal balance during molding execution. Figure 4 As shown, if the thermal balance during molding is considered, the heat generation E during molding with the cylinder 22 maintained at the set temperature is H1 Add the moving heat E from the front (nozzle 25 side) A0 The results are related to the heat transfer E of the resin Ti Add the heat dissipation E from the heater 24b to the outside of the cylinder 22 Ri and the heat transfer amount E to the rear (opposite side of the nozzle 25) A1 The results are consistent.

[0062] Figure 5 This is a schematic diagram illustrating the thermal balance when molding stops. Figure 5 As shown in FIG, if the thermal balance when molding is stopped is considered, the resin inside the barrel 22 is in a stagnant state where the screw 23 is stopped and the resin does not flow, unlike when molding is in progress. In this state, it can be considered that the resin temperature is the same as the temperature of the barrel 22, so the heat generated by the heater 24b is not transferred to the resin. Figure 5 As shown, the heat generation E' when the molding is stopped while the cylinder 22 is maintained at the set temperature H1 Add the moving heat E from the front (nozzle 25 side) A0 The result is the heat dissipation E outside the barrel 22 Ri Add the heat transfer E to the rear (opposite side of the nozzle 25) A1 The results are consistent.

[0063] Therefore, the heat generated by E H1 Subtract calorific value E′H1 To offset various heat dissipation equations (3). As shown in equation (3), it is possible to calculate the heat generated during molding based on the heat generated during molding. Hi and the heat generation E' when molding stops Hi To calculate the heat transfer E Ti .

[0064] The calculation of shear heat generation by the calculation unit 15 will be described. The calculation unit 15 calculates the shear heat generation caused by the rotation of the screw 23 based on the motion information acquired by the motion information acquisition unit 11 and the characteristic information acquired by the characteristic information acquisition unit 12. The shear heat generation is the amount of heat generated by shearing caused by the rotation of the screw 23.

[0065] An example of a method for calculating the shear heat value by the calculation unit 15 is described. The calculation unit 15 integrates the torque of the screw 23 during the metering operation based on the motor operation information and characteristic information to calculate the energy E for rotating the screw 23. D For example, the energy E of the rotational drive screw 23 is calculated by the following formula (4): D In addition, E in formula (4) D represents the energy of the rotary drive screw 23, K T represents the torque constant of the rotary motor that rotates the screw 23 , r represents the motor current during measurement, R represents the reduction ratio between the motor and the screw 23 , ω represents the rotational angular velocity of the screw 23 , and η represents the mechanical efficiency.

[0066] [Number 4]

[0067]

[0068] If all the energy calculated by equation (4) is the shear heat of the resin, the energy E that drives the screw 23 is D Directly the shear heat E S (E D =E S However, when excessive heat is generated by the rotation of the screw 23, the temperature inside the barrel 22 becomes higher than the temperature outside the barrel 22, and the amount of heat transferred by the heater E Ti There is a negative value (heat transfer from the inside to the outside). This heat is due to the energy E of the rotational drive screw 23. D , so E D =E S Therefore, as shown in formula (5), it is necessary to use the amount of negative heat transfer value (negative heater heat transfer E Ti The sum of the shear heating value is corrected. This means that E D Part of the heat is dissipated. In formula (5), E Ti Negative values ​​only.

[0069] [Number 5]

[0070]

[0071] In addition, the calculation unit 15 calculates the amount of heat transferred E from the heaters 24a to 24d. Ti and shear heat E S To calculate the total heat E of the molding material M Total heat E M For example, the following formula (6) can be used for calculation. Ti If there is a negative value, it is treated as 0 and used in calculations.

[0072] [Number 6]

[0073]

[0074] The above describes the calculation of the calorific value, the heat transfer value, and the shear heat value by the calculation unit 15. Next, the output unit 20 that outputs the calculation results of the calculation unit 15 will be described.

[0075] The output unit 20 performs processing for displaying information based on the calculation results of the calculation unit 15 on the display device 6. The output unit 20 may be configured to output the calculation results of the calculation unit 15 to a computer connected to the outside of the injection molding machine 1 separately from the display device 6 of the injection molding machine 1.

[0076] then, Figure 6 This is a diagram showing an example of the energy flow inside the cylinder 22 displayed on the display device 6 by the output unit 20 according to the first embodiment. Figure 7 This is a diagram showing an example of a table displayed on the display device by the output unit 20 according to the first embodiment.

[0077] exist Figure 6 The shear heat E is shown together with the position of the screw 23 inside the barrel 22. S In addition, the corresponding heat transfer E is shown at the position of heater 24a. T0 , the corresponding heat transfer E is shown at the position of heater 22b T1 , the corresponding heat transfer E is shown at the position of heater 22c T2 , the corresponding heat transfer E is shown at the position of heater 24d T3 In addition, the total heat received E is displayed at the position of the nozzle 25. m .

[0078] exist Figure 7 The shear heat value E is shown in the table S The calculation results and heat transfer E T0 The calculation results and heat transfer ET1 The calculation results and heat transfer E T2 The calculation results and heat transfer E T3 The calculation result, total heat E m In this table, the heat transfer amount of each area of ​​heater 24a to heater 24d is displayed separately.

[0079] The output unit 20 executes, for example, Figure 6 Images of the content shown, Figure 7 The image of the content shown is displayed on the display device 6 at the same time or selectively by switching operation. Figure 6 The content shown, Figure 7 The content shown here can help us understand the heat transfer E of each area of ​​heater 24a to heater 24d. Ti , shear heat E S Total heat E m .

[0080] Next, refer to Figures 8 to 10 , different display examples are explained. Figure 8 FIG. 1 is a diagram showing an example of a bar graph displayed on the display device 6 by the output unit 20 of the first embodiment. Figure 8 In the bar graph, the heat transfer E of the heater 22b is displayed in a manner that visually distinguishes the display area. T1 , the heat transfer E of heater 22c T2 , the heat transfer E of heater 24d T3 , shear heat E S In addition, the heat transfer amount E of the heater 24a at the nozzle portion 25 is T0 The contribution of is very small and is therefore omitted.

[0081] Figure 9 FIG. 1 is a diagram showing an example of a pie chart displayed on the display device 6 by the output unit 20 of the first embodiment. Figure 9 In the pie chart, the heat transfer E of the heater 22b is also displayed in a manner that visually distinguishes the display area. T1 , the heat transfer E of heater 22c T2 , the heat transfer E of heater 24d T3 , shear heat E S In addition, the heat transfer amount E of the heater 24a at the nozzle portion 25 is T0 The contribution of is very small and is therefore omitted.

[0082] Figure 10 : is a diagram showing an example of the energy flow and calculation results inside the cylinder 22 displayed on the display device 6 by the output unit 20 of the first embodiment. Figure 10 Shown in Figure 6The same inside of the barrel 22, the positions of the heaters 24a to 24d, and the shear heat value E are displayed. S Heater heat transfer E T0 Heater heat transfer E T1 Heater heat transfer E T2 Heater heat transfer E T3 Total heat E m The user confirms the result of the operation. Figure 10 The content shown can intuitively grasp the heat transfer amount of the heaters 24a to 24d in each area.

[0083] Next, refer to Figure 11 A series of flow of display processing will be described. Figure 11 This is a flowchart showing an example of the flow of display processing by the control device 10 of the injection molding machine 1 according to the first embodiment.

[0084] First, the characteristic information acquisition unit 12 acquires characteristic information indicating the characteristics of the injection molding machine 1 (step S10), and the operation information acquisition unit 11 acquires the operating rate related to the operation of the heaters 24a to 24d as operation information (step S11). The operation information and characteristic information are acquired from, for example, various sensors, a storage unit (not shown) of the control device 10, an external computer (not shown), and the like.

[0085] The calculation unit 15 calculates the heating value of the heaters 24a to 24d based on the acquired operation information and characteristic information (step S12). The calculation unit 15 calculates the heating value of each heater 24a to 24d when the cylinder 22 is maintained at a predetermined set temperature based on, for example, the operating rate of the heaters 24a to 24d and the capacity of the heaters 24a to 24d.

[0086] Next, the calculation unit 15 calculates the amount of heat transferred from the heaters 24a to 24d to the resin (step S13). For example, the calculation unit 15 calculates the amount of heat generated by the heaters 24a to 24d during molding. Hi and the heat generation E′ of the heaters 24a to 24d when molding is stopped Hi Substituting into the above formula (2), we can calculate the heat transfer E from heaters 24a to 24d to the resin. Ti .

[0087] Next, the calculation unit 15 calculates the shear heating value based on the motion information acquired by the motion information acquisition unit 11 and the characteristic information acquired by the characteristic information acquisition unit 12 (step S14 ).

[0088] Next, the output unit 20 performs processing for displaying information based on the calculation result of the calculation unit 15 on the display device 6 (step S15). In this processing, the output unit 20 performs processing for displaying numerical values, characters, symbols, graphs, pictures, or a combination thereof representing the calculation result of the calculation unit 15. For example, the output unit 20 displays Figures 6 to 10 The image of the displayed content is output to the display device 6 .

[0089] After the output unit 20 processes step S15, the control device 10 returns to step S11 to continue the molding process and re-executes the processes from step S11 onward (step S16: Yes). On the other hand, if the control device 10 detects that the molding process has stopped, it executes a process to stop the molding process and ends the flow (step S16: No). Whether to continue or stop the molding process is determined by the control device 10, for example, based on user operations and whether the plasticization state meets predetermined conditions.

[0090] According to the control device 10 of the injection molding machine 1 involved in the first embodiment described above, the following effects are achieved. That is, the injection molding machine 1 includes a barrel 22, a plurality of heaters 24a to 24d arranged in the barrel 22 along the axial direction, and a screw 23 arranged inside the barrel 22. The control device 10 of the injection molding machine 1 includes: an action information acquisition unit 11, which acquires action information related to the action of the heaters 24a to 24d and the screw 23; a characteristic information acquisition unit 12, which acquires characteristic information related to the characteristics of the injection molding machine 1; and a calculation unit 15, which calculates the amount of heat transferred E from the heaters 24a to 24d to the molding material for each of the plurality of heaters 24a to 24d divided along the axial direction based on the acquired action information and characteristic information. Ti , and calculate the shear heat E that the molding material receives due to the action of the screw 23 S And an output portion 20, which performs the heat transfer E Ti and shear heat E S Together, the calculation results of the calculation unit 15 are displayed separately for each of the plurality of regions divided in the axial direction on the display device 6. The functions of the control device 10 are implemented by programs stored in the storage unit (storage medium).

[0091] Therefore, the shear heat E S and the heat transfer E of each area TiThe information is displayed on the display device 6, allowing the user to accurately grasp the plasticization state within the barrel 22. This grasped plasticization state can be used as an indicator for adjusting injection molding conditions. For example, if there is a recommended optimal distribution of various energies based on the material used, the molding conditions can be adjusted so that the output energy details approximate this optimal distribution. Furthermore, the information output by the output unit 20 can be used to identify the cause of molding defects.

[0092] In this embodiment, the calculation unit 15 calculates the heating value E of the heaters 24a to 24d when the molding is performed while the cylinder 22 is maintained at a predetermined set temperature. Hi and the heat generation E′ of the heaters 24a to 24d when the molding is stopped while the cylinder 22 is maintained at a predetermined set temperature. Hi Calculate the heat transfer E from heaters 24a~24d to the molding material Ti Therefore, even in continuous molding, the user can accurately grasp the plasticization state of the resin without the need for special sensors. There is no need to add sensors to the barrel 22, and the heat transfer E can be calculated based on the information originally collected and owned by the injection molding machine 1. Ti .

[0093] In addition, in this embodiment, the output unit 20 displays at least one of a table, a bar graph, a pie chart, a bar graph, and an energy flow diagram on the display device 6. Thus, the plasticization state (shear heat value E) in the barrel 22 is displayed in a visually easy-to-understand form. S , heat transfer E Ti ), so users can grasp the plasticizing status intuitively and more easily.

[0094] The structure of the first embodiment has been described above. Hereinafter, an embodiment having a structure different from the first embodiment will be described.

[0095] [Second embodiment]

[0096] The energy balance around the barrel 22 during plasticization can be expressed by the following equation (7). The input energy on the left is the calorific value E of each heater 24a to 24d used for plasticization of the material. Hi The total of the energy E of the rotating drive screw 23 D The right side shows the heat transfer E of each heater 24a~24d as effective energy. Ti The total and shear calorific value E S Add the heat dissipation E of each heater 24a to 24d which is not used for plasticization of the resin and is ineffective energy. RiIn addition, there is also energy that moves between the areas of each heater inside the cylinder 22, but this moving energy does not appear in the overall energy balance and is therefore not included in the formula (7).

[0097] [Number 7]

[0098]

[0099] Figure 12 This is a diagram showing an example of energy flow inside the cylinder 22 displayed on the display device 6 by the output unit 20 of the second embodiment. The output unit 20 of the second embodiment performs the heat generation E of the heater as input energy. Hi and the energy E of the rotational drive screw 23 D The calculation result is displayed on the display device 6. As described in the first embodiment, the calculation unit 15 calculates the calorific value E. Hi and the energy E of the rotational drive screw 23 D .

[0100] The heat value E calculated by the calculation unit 15 Hi The calculation results of each of the heaters 24a to 24d are displayed on the display device 6. For example, the heat generation E at the heater 24a H0 , Heat E generated at heater 24b H1 , Heat E generated at heater 24c H2 , Heat E generated at heater 24d H3 It is displayed as the calculation result.

[0101] Heat generation E of heaters 24a to 24d Hi For example, Figure 7 table, Figure 8 Column chart, Figure 9 The output unit 20 displays each of the plurality of regions divided along the axial direction as in a pie chart. Figure 12 The energy flow shown is displayed on the display device 6 together with these calculation results. Figure 10 As shown in Figure 12 The numerical values ​​of the calculation results are displayed in parallel in the energy flow.

[0102] As described above, the calculation unit 15 of the second embodiment calculates the energy used to rotate the screw 23. Consequently, the input energy during the plasticizing process is output as the calculation result to the display device 6, allowing the user to fully grasp the energy balance. The ratio of input energy to effective energy is easily understood, allowing the user to easily assess energy efficiency. The user can search for optimal conditions while considering the balance between the plasticizing state (quality) and energy efficiency.

[0103] [Third embodiment]

[0104] Figure 13 is a diagram illustrating the heat balance taking into account the amount of heat dissipated. Figure 13 , the heat balance when molding is being executed and when molding is stopped is shown in a table format for each of the heaters 24 a to 24 d. Figure 14 This is a diagram showing an example of the energy flow inside the cylinder 22 displayed on the display device 6 by the output unit 20 according to the third embodiment.

[0105] The calculation unit 15 of the third embodiment calculates the ineffective energy during plasticization, that is, the amount of heat dissipated E from each area of ​​the heaters 24a to 24d to the outside of the cylinder 22. Ri .

[0106] The calculation unit 15 calculates the heat transfer amount E in the cylinder 22 using Fourier's law based on the temperature gradient in the axial direction of the cylinder 22, the cross-sectional area of ​​the cylinder 22, and the thermal conductivity. Ai The axial temperature gradient of the barrel 22 can be calculated based on the position of each control point and the set temperature. In addition, when the set temperature of adjacent areas is the same, the moving heat E Ai It is 0 and calculation is unnecessary. In addition, the direction from the front end side (injection side) toward the rear end side (base end side) of the cylinder 22 is defined as positive.

[0107] exist Figure 13 In the table, the moving heat E A0 The amount of heat transfer between the area of ​​the heater 24a at the nozzle portion 25 and the area of ​​the heater 24b adjacent to the rear end side of the heater 24a is shown. A1 The amount of heat transferred between the area of ​​heater 24b and the area of ​​heater 24c adjacent to the rear end of heater 24b is shown. A2 The amount of heat transfer between the area of ​​the heater 24 c and the area of ​​the heater 24 d adjacent to the rear end side of the heater 24 c is indicated.

[0108] The calculation unit 15 calculates the amount of heat E Ai and the heat generation E' when molding stops Hi Calculate the heat dissipation E from each area to the outside of the barrel 22 Ri When using Figure 13 When the heat balance formula shown in the table is used, the heat dissipation E in the area of ​​the heater 24a at the nozzle portion 25 is R0 The heat generated when the molding stops can be measured by E' H0 Subtract the moving heat E A0 The heat dissipation E R0 In addition to the amount of heat dissipated from the surface of the heater 24a to the atmosphere, the amount of heat dissipated to the contacting mold is also included.

[0109] Similarly, the heat dissipation E in the area of ​​the heater 24b is R1 The heat generated when the molding stops can be measured by H1 Plus moving heat E A0 The value obtained minus the transfer heat E A1 The heat dissipation E in the area of ​​heater 24c is calculated. R2 The heat generated when the molding stops can be measured by H2 Plus moving heat E A1 The value obtained minus the transfer heat E A2 The heat dissipation E in the area of ​​heater 24d is calculated. R3 The heat generated when molding stops E' H3 Plus moving heat E A2 The heat dissipation E R3 In addition to the amount of heat dissipated from the surface of the heater 24d to the atmosphere, the amount of heat dissipated to the cooling water and the machine body is also included.

[0110] The output unit 20 will Figure 14 The energy flow shown is displayed on the display device 6, and the heat dissipation E is displayed using a table, a bar graph, a pie chart, etc. Ri The calculation result of is displayed in a manner that can be distinguished for each of the multiple regions divided along the axial direction. Figure 14 In addition to showing the shear heat E S Heater heat transfer E Ti Total heat E m , the energy E of the rotational drive screw 23 D , calorific value E Hi In addition, the heat dissipation E is also shown Ri The output portion 20 may also be as follows Figure 10 As shown in Figure 14 The energy flow including the heat dissipation E is shown in parallel Ri The numerical value of the operation result.

[0111] As described above, the calculation unit 15 of the third embodiment calculates the amount of heat transferred within the cylinder 22 E for each of the plurality of regions divided in the axial direction. Ai .

[0112] In this embodiment, the calculation unit 15 calculates the transfer heat E in the cylinder 22 based on the cross-sectional shape of the cylinder 22, the position and temperature of each cylinder temperature control point, and the thermal conductivity. Ai This makes it possible to calculate the transfer energy without performing complicated processing.

[0113] Furthermore, in this embodiment, the calculation unit 15 calculates the amount of heat dissipated to the outside of the barrel 22 for each of the multiple axially divided regions. This allows the ineffective energy during the plasticizing process to be displayed as a calculation result by the calculation unit 15. Therefore, by adding the ineffective energy to the display on the display device 6, a more comprehensive understanding of the energy balance can be achieved.

[0114] In this embodiment, the calculation unit 15 calculates the amount of heat transferred E in the cylinder 22. Ai and the heat generation E of the heaters 24a to 24d when the molding is stopped while the cylinder 22 is maintained at a predetermined set temperature. Hi , to calculate the heat dissipation E outside the barrel 22 Ri Therefore, the heat dissipation E can be calculated without adding sensors or performing complex processing. Ri .

[0115] [Fourth embodiment]

[0116] Figure 15 This is a diagram showing an example of the energy flow and calculation results inside the cylinder 22 displayed on the display device 6 by the output unit 20 of the fourth embodiment. In addition to displaying the heat dissipation E described in the third embodiment, the output unit 20 of the fourth embodiment Ri In addition, it will move heat E Ai The calculation result is displayed on the display device 6.

[0117] exist Figure 15 In the case of shear heat E S Heater heat transfer E Ti Total heat E m , the energy E of the rotational drive screw 23 D , calorific value E Hi 、Heat dissipation E Ri , moving heat E Ai The calculation results (numerical values) of each heat quantity are displayed together with the energy flow. The calculation method of each heat quantity is the same as that of the above embodiment.

[0118] The output unit 20 can also be Figure 15 Various heat quantities are displayed on the display device 6 in different forms. Figure 16 This is a diagram showing an example of a table displayed on the display device 6 by the output unit 20 according to the fourth embodiment.

[0119] exist Figure 16 In the table, the calorific value E Hi The numerical value of the calculation result, the energy E of the rotation drive screw 23 D The numerical value of the calculation result and the total value of the calculation result are expressed as input energy. Heater heat transfer E Ti, shear heat E S And the total heat E m The numerical value of the calculation result is expressed as effective energy. Heat dissipation E Ri The numerical value of the calculation result and the total value of the calculation result are expressed as invalid energy. Hi Heater heat transfer E Ti And the heat dissipation E Ri The numerical value of the calculation result is shown for each area of ​​each heater 24a to 24d. Ai The heat transfer E of each heater is shown as the transfer energy Ti The position between heaters 24a~24d can be determined.

[0120] Figure 17 FIG. 1 is a diagram showing an example of a bar graph displayed on the display device 6 by the output unit 20 of the fourth embodiment. Figure 17 The heat generation E of each area of ​​heater 24a~heater 24d is Hi The energy E of the rotating drive screw 23 D The composition ratio of the input energy is expressed by dividing the strip area into quadrilateral areas. Figure 17 The lower part shows the effective energy of each heater 24a ~ heater 24d Heat transfer E Ti and shear heat E S The composition ratio and the heat dissipation E as ineffective energy Ri The composition ratio of . Also, the transfer heat E as transfer energy is shown between the upper and lower bars. Ai .

[0121] The output unit 20 can, for example, Figure 16 table, Figure 17 The bar chart with Figure 15 Energy flow from Figure 15 The energy flow of the calculation result is omitted. Figure 1 The display device 6 displays the information.

[0122] [Fifth embodiment]

[0123] In the fifth embodiment, the heat transfer capacity E of each heater 24a to 24d is Ti The total heat E M The output unit 20 outputs the heat transfer E of the heater 24a. T0 Relative to the total heat E M The ratio of the heat transfer E of the heater 24b T1 Relative to the total heat E M The ratio of the heat transfer E of the heater 24c T2Relative to the total heat E M The ratio of the heat transfer E of the heater 24d T3 Relative to the total heat E M The ratio is output to the display device 6.

[0124] In the fifth embodiment, the calculation unit 15 calculates the amount of heat transferred E from the heaters 24a to 24d. Ti and shear heat E S Calculate the total heat E of the molding material M The output unit 20 outputs the heat transfer E from at least the heaters 24a to 24d in the calculation result of the calculation unit 15. Ti and shear heat E S The total heat E M The ratio used as a reference is outputted. This makes it easier to grasp the ratio of the contribution of the heat transfer amount and the shear heat amount from each heater during plasticization.

[0125] Example

[0126] Next, an example will be described in which injection molding is actually performed using the control device 10 of the above-described embodiment. Figure 18 is a table showing conditions of a calculation example of the control device 10 of this embodiment. Figure 18 The table shows multiple conditions for injection molding. Condition 1 in the table includes a set temperature of 220°C for heater 24a, a set temperature of 220°C for heater 24b, a set temperature of 220°C for heater 24c, a set temperature of 220°C for heater 24d, a set temperature of 50°C under the hopper, a rotation speed of 50 rpm, and a cycle time of 30 s. Condition 2 includes a set temperature of 220°C for heater 24a, a set temperature of 220°C for heater 24b, a set temperature of 220°C for heater 24c, a set temperature of 220°C for heater 24d, a set temperature of 50°C under the hopper, a rotation speed of 300 rpm, and a cycle time of 15 s. Condition 3 includes a set temperature of 220°C for heater 24a, a set temperature of 220°C for heater 24b, a set temperature of 200°C for heater 24c, a set temperature of 180°C for heater 24d, a set temperature of 50°C under the hopper, a rotation speed of 50 rpm, and a cycle time of 30 s. Condition 4 sets the temperature of heater 24a at 220°C, heater 24b at 220°C, heater 24c at 200°C, and heater 24d at 180°C. The temperature below the hopper is set at 50°C, the rotation speed is 300 rpm, and the cycle time is 15 seconds. Conditions 1 through 4 share a common screw diameter of 32 mm, polypropylene (PP) resin, a metering stroke of 64 mm, and a back pressure of 2 MPa.

[0127] Figure 19It is a bar graph showing the calculation results of the control device 10 according to the present embodiment. Figure 19 The figure shows the Figure 18 The calculation results when injection molding was performed under conditions 1 to 4 are shown in the table. In addition, the contribution of the heat transfer of the heater 24a in the nozzle portion 25 is very small and is therefore omitted.

[0128] Figure 19 The height of the vertical axis represents the total heat received by the resin (molding material). Since the set temperature of the front end side of the barrel 22 is the same, it can be seen that the total heat received is not much different, but the proportion of each heat is greatly different.

[0129] In condition 1, the resin is fully preheated by heater 24d located on the upstream side of the flow path, and a lot of heat is also obtained in heater 24c. Since only a small amount of heat is obtained at heater 24b located downstream of the flow path, when it reaches this area (metering section), it can be read that the resin temperature is roughly the same as the setting. In addition, the supply amount is difficult to control, and the heat generated by shearing is small, which is unstable in each cycle. Therefore, it can be seen that this is a condition that can obtain very good plasticization quality. In conditions 2 and 3, the preheating received by heater 24d becomes less, and the heat caused by shearing becomes more, so it can be seen that the plasticization quality deteriorates compared to condition 1. However, condition 3 compensates for the reduction in preheating in heater 24d by heater 24c, so it can be seen that the plasticization quality is better than condition 2. In condition 4, there is almost no preheating in heater 24d, and the heat supply based on shearing accounts for the majority. Therefore, it can be seen that condition 4 is a condition where the plasticization quality is likely to become unstable. Furthermore, the amount of heat generated by heater 24b located downstream in the flow path is also quite high, so it is believed that heat supply was insufficient, and the resin temperature in the metering section was significantly lower than the set temperature. This situation is believed to cause poor filling within the mold, and the load applied to screw 23 and screw head 30 during metering increases, increasing the possibility of damage. Thus, this example demonstrates that the control device 10 of this embodiment can accurately grasp the plasticization state.

[0130] The above series of processes can be executed by hardware or by software. In other words, the above functional structure is just an example and is not particularly limited. That is, as long as the computer has the function of executing the above series of processes as a whole, the function blocks used to implement the function are not particularly limited to the above examples. In addition, the location of the function blocks is not particularly limited and can be arbitrary. For example, a function block can be composed of a hardware unit, a software unit, or a combination of them. In the case of executing a series of processes by software, the program constituting the software is installed from a network or a recording medium to a computer, etc. The computer can also be a computer assembled on dedicated hardware. In addition, the computer can also be a computer that can execute various functions by installing various programs, such as a general-purpose smartphone or personal computer other than a server.

[0131] The recording medium containing such a program may include not only removable media (not shown) that is separately disposed from the device body in order to provide the program to a user, etc., but also recording media that is provided to the user, etc., pre-assembled in the device body. Since the program can be distributed via a network, the recording medium may also be a recording medium that is mounted on or accessible to a computer connected to or capable of being connected to a network. Furthermore, the steps describing the program recorded on the recording medium naturally include processing that is performed in a time-series manner according to the order in which they are performed, as well as processing that is not necessarily performed in a time-series manner but can be executed in parallel or independently.

[0132] The present disclosure has been described in detail, but the present disclosure is not limited to the above-mentioned embodiments. These embodiments can be variously added, 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 recorded in the claims and their equivalents. In addition, these embodiments can also be implemented in combination. For example, in the above-mentioned embodiments, the order of each action and the order of each processing are shown as an example and are not limited to this. In addition, the same applies to the case where numerical values ​​or formulas are used in the description of the above-mentioned embodiments.

[0133] The following supplementary notes are also disclosed regarding the above-mentioned embodiment and modifications.

[0134] (Note 1)

[0135] A control device (10) for an injection molding machine (1), the injection molding machine (1) comprising a barrel (22), a plurality of heaters (24a-24d) arranged axially in the barrel (22), and a screw (23) arranged inside the barrel (22), wherein the control device (10) for the injection molding machine (1) comprises:

[0136] an action information acquisition unit (11) for acquiring action information related to the actions of the heaters (24a-24d) and the screw (23);

[0137] a characteristic information acquisition unit (12) for acquiring characteristic information related to the characteristics of the injection molding machine;

[0138] a calculation unit (15) for calculating the amount of heat transferred from the heaters (24a-24d) to the molding material for each of the plurality of heaters (24a-24d) divided along the axial direction based on the acquired motion information and characteristic information, and calculating the amount of shear heat generated by the molding material due to the motion of the screw (23); and

[0139] An output unit (20) performs processing for displaying the heat transfer amount and the shear heat amount as calculation results of the calculation unit (15) on a display device (6) in a manner that is differentiated for each of a plurality of areas divided in the axial direction.

[0140] (Note 2)

[0141] In the control device (10) of the above-mentioned injection molding machine (1),

[0142] The calculation unit (15) calculates the amount of heat transferred from the heater (24a~24d) to the molding material based on the heat generated by the heater (24a~24d) when molding is executed while maintaining the barrel (22) at a specified set temperature and the heat generated by the heater (24a~24d) when molding is stopped while maintaining the barrel (22) at a specified set temperature.

[0143] (Note 3)

[0144] In the control device (10) of the above-mentioned injection molding machine (1),

[0145] The calculation unit (15) calculates the energy for rotationally driving the screw (22).

[0146] (Note 4)

[0147] In the control device (10) of the above-mentioned injection molding machine (1),

[0148] The calculation unit (15) calculates the amount of heat transferred within the barrel (22) between each of a plurality of areas divided in the axial direction.

[0149] (Note 5)

[0150] In the control device (10) of the above-mentioned injection molding machine (1),

[0151] The calculation unit (15) calculates the amount of heat transferred within the barrel (22) based on the cross-sectional shape of the barrel (22), the position and temperature of each barrel temperature control point, and thermal conductivity.

[0152] (Note 6)

[0153] In the control device (10) of the above-mentioned injection molding machine (1),

[0154] The calculation unit (15) calculates the amount of heat dissipated to the outside of the barrel (22) for each of a plurality of areas divided along the axial direction.

[0155] (Note 7)

[0156] In the control device (10) of the above-mentioned injection molding machine (1),

[0157] The calculation unit (15) calculates the amount of heat dissipated outside the barrel (22) based on the amount of heat transferred within the barrel (22) and the amount of heat generated by the heaters (24a-24d) when molding is stopped while maintaining the barrel (22) at a predetermined set temperature.

[0158] (Note 8)

[0159] In the control device (10) of the above-mentioned injection molding machine (1),

[0160] The calculation unit (15) calculates the total heat received by the molding material based on the heat transfer from the heaters (24a-24d) and the shear heat.

[0161] The output unit (20) outputs, among the calculation results of the calculation unit (15), at least the heat transfer amount and the shear heat amount from the heaters (24a to 24d) in a ratio based on the total heat reception amount.

[0162] (Note 9)

[0163] In the control device (10) of the above-mentioned injection molding machine (1),

[0164] The output unit (20) displays at least one of a table, a column chart, a pie chart, a bar chart, and an energy flow chart on the display device (6).

[0165] (Note 10)

[0166] A computer for controlling an injection molding machine (1) having a barrel (22), a plurality of heaters (24a to 24d) arranged in the barrel (22) along the axial direction, and a screw (23) arranged inside the barrel (22) is caused to execute the following functions:

[0167] An action information acquisition function for acquiring action information related to the actions of the heaters (24a-24d) and the screw (23);

[0168] a characteristic information acquisition function for acquiring characteristic information related to the characteristics of the injection molding machine;

[0169] a calculation function for calculating, based on the acquired motion information and characteristic information, the amount of heat transferred from the heater (24a-24d) to the molding material for each of the plurality of heater (24a-24d) regions divided along the axial direction, and calculating the amount of shear heat generated by the molding material due to the motion of the screw (23); and

[0170] The output function performs processing for displaying the heat transfer amount and the shear heat amount as the calculation results of the calculation function on a display device (6) in a manner that is divided into each of the plurality of areas divided in the axial direction.

[0171] Description of Reference Numerals

[0172] 1: injection molding machine; 10: control device; 11: motion information acquisition unit; 12: characteristic information acquisition unit; 15: calculation unit; 20: output unit.

Claims

1. A control device for an injection molding machine, comprising: a barrel, a plurality of heaters arranged axially along the barrel, and a screw arranged inside the barrel, the control device for the injection molding machine comprising: an operation information acquiring unit configured to acquire operation information related to the operation of the heater and the screw; a characteristic information acquiring unit that acquires characteristic information related to characteristics of the injection molding machine; a calculation unit for calculating, based on the acquired motion information and characteristic information, an amount of heat transferred from the heater to the molding material for each of a plurality of zones of the heater divided along the axial direction, and calculating an amount of shear heat generated by the molding material due to the motion of the screw; as well as The output unit performs processing for displaying the heat transfer amount and the shear heat amount as calculation results of the calculation unit on a display device in a manner separate from each of the plurality of areas divided in the axial direction.

2. The control device for an injection molding machine according to claim 1, wherein: The calculation unit calculates the amount of heat transferred from the heater to the molding material based on the amount of heat generated by the heater when molding is executed while the cylinder is maintained at a predetermined set temperature and the amount of heat generated by the heater when molding is stopped while the cylinder is maintained at a predetermined set temperature.

3. The control device for an injection molding machine according to claim 1 or 2, wherein: The calculation unit calculates energy for rotationally driving the screw.

4. The control device for an injection molding machine according to any one of claims 1 to 3, wherein: The calculation unit calculates the amount of heat transferred within the cylinder between each of a plurality of regions divided in the axial direction.

5. The control device for an injection molding machine according to claim 4, wherein: The calculation unit calculates the amount of heat transferred within the barrel based on a cross-sectional shape of the barrel, positions and temperatures of each barrel temperature control point, and thermal conductivity.

6. The control device for an injection molding machine according to any one of claims 1 to 5, wherein: The calculation unit calculates the amount of heat dissipated to the outside of the barrel for each of a plurality of regions divided in the axial direction.

7. The control device for an injection molding machine according to claim 6, wherein: The calculation unit calculates the amount of heat dissipated outside the cylinder based on the amount of heat transferred within the cylinder and the amount of heat generated by the heater when molding is stopped while the cylinder is maintained at a predetermined set temperature.

8. The control device for an injection molding machine according to any one of claims 1 to 7, wherein: The calculation unit calculates the total heat received by the molding material based on the heat transferred from the heater and the shear heat. The output unit outputs at least the heat transfer amount and the shear heating amount from the heater, among the calculation results of the calculation unit, at a ratio based on the total heat reception amount.

9. The control device for an injection molding machine according to any one of claims 1 to 8, wherein: The output unit displays at least one of a table, a bar graph, a pie chart, a bar graph, and an energy flow graph on the display device.

10. A program for causing a computer that controls an injection molding machine including a barrel, a plurality of heaters arranged in the barrel along an axial direction, and a screw arranged inside the barrel to execute the following functions: An action information acquisition function for acquiring action information related to the actions of the heater and the screw; a characteristic information acquisition function for acquiring characteristic information related to the characteristics of the injection molding machine; a calculation function for calculating, based on the acquired motion information and characteristic information, the amount of heat transferred from the heater to the molding material for each of the plurality of heater regions divided along the axial direction, and calculating the amount of shear heat generated by the molding material due to the screw motion; and The output function performs processing for displaying the heat transfer amount and the shear heat amount as calculation results of the calculation function on a display device in a manner separate from each of the plurality of areas divided in the axial direction.

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