Kneading device and kneading method

Abstract

To provide a kneading device and a kneading method capable of suppressing failure of kneading.SOLUTION: A kneading device 1 for obtaining a kneaded product by mixing resin and a filler by a rotor includes a kneader 10 having a temperature sensor 101 capable of detecting temperature of the kneaded product and a rotation sensor 102 capable of detecting the number of rotations of the rotor, and a kneader control portion 11 for controlling the kneader 10. The kneader control portion 11 includes: a tensile strength estimation processing portion 24 for estimating tensile strength of the kneaded product at the present point of time on the basis of temperature of the kneaded product detected by the temperature sensor 101 and the number of rotations of the rotor detected by the rotation sensor 102; and a kneading condition control processing portion 25 for obtaining a deviation from target tensile strength at the present point of time and the tensile strength of the kneaded product at the present point of time estimated by the tensile strength estimation processing portion 24 on the basis of the target tensile strength, which is a preset target value for time change in tensile strength of the kneaded product from a start of kneading, and controlling the kneading condition of the kneader 10 so as to reduce the deviation.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a kneading device and a kneading method. [Background technology]

[0002] For example, the desired material is produced by mixing (kneading) viscous resins such as rubber or plastic before crosslinking with various additives and compounding agents (fillers) using a kneading device such as a batch mixer kneader.

[0003] Patent Document 1 discloses flow analysis of a kneaded material. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-161853 Summary of the Invention [Problem to be solved by the invention]

[0005] However, if the kneading conditions are not properly controlled, the kneading may not go well and may fail.

[0006] Therefore, an object of the present invention is to provide a kneading device and a kneading method that can prevent kneading failures. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides a kneading device that mixes a resin and a filler to obtain a kneaded product, comprising: a kneading machine having a temperature sensor that can detect the temperature of the kneaded product and a rotation sensor that can detect the rotor rotation speed; and a kneading machine control unit that controls the kneading machine, wherein the kneading machine control unit has: a tensile strength estimation processing unit that estimates the tensile strength of the kneaded product based on the temperature of the kneaded product detected by the temperature sensor and the rotor rotation speed detected by the rotation sensor; and a kneading condition control processing unit that controls the kneading conditions of the kneading machine so as to reduce the deviation between the tensile strength estimated by the tensile strength estimation processing unit and a target tensile strength, which is a preset target value for the change in tensile strength of the kneaded product over time from the start of kneading.

[0008] Furthermore, in order to solve the above-mentioned problems, the present invention provides a kneading method for mixing a resin and a filler to obtain a kneaded product, which uses a kneading machine having a temperature sensor capable of detecting the temperature of the kneaded product and a rotation sensor capable of detecting the rotor rotation speed, estimates the tensile strength of the kneaded product based on the temperature of the kneaded product detected by the temperature sensor and the rotor rotation speed detected by the rotation sensor, and controls the kneading conditions of the kneading machine so as to reduce the deviation between the estimated tensile strength and a target tensile strength, which is a preset target value for the change in tensile strength of the kneaded product over time from the start of kneading. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a kneading device and a kneading method that can suppress kneading failures. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic configuration diagram of a kneading device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram illustrating the kneading process. [Figure 3] 1 is a graph showing both the measured values ​​of tensile strength S and the calculated values ​​of tensile strength S. [Figure 4]1 is a flow diagram of a kneading method according to an embodiment of the present invention. [Figure 5] 10A is a flow diagram of the test manufacturing data acquisition process, FIG. 10B is a flow diagram of the relationship derivation process, and FIG. 10C is a flow diagram of the prerequisite data acquisition process. [Figure 6] FIG. 10 is a flow diagram of a tensile strength estimation process. [Figure 7] FIG. 10 is a flowchart of a kneading failure determination process. [Figure 8] FIG. 10 is a flow diagram of a kneading condition control process. [Figure 9] FIG. 10 is a graph showing an example of setting a target tensile strength and the change in the tensile strength of the kneaded material over time when this setting example is used. DETAILED DESCRIPTION OF THE INVENTION

[0011] [Embodiment Mode] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0012] Fig. 1 is a schematic diagram of a kneading device 1 according to the present embodiment. As shown in Fig. 1, the kneading device 1 according to the present embodiment is a device that mixes a resin and a filler with a rotor to obtain a kneaded product, and includes a kneader 10 and a kneader control unit 11 that controls the kneader 10.

[0013] The kneader 10 is, for example, a batch kneader, and is configured to mix the resin and filler with a rotor that rotates in a kneading chamber. The kneader 10 is configured so that the temperature of the kneaded material and the rotor rotation speed, which is the rotation speed of the rotor, can be set, and is configured to be driven according to the set values ​​of the temperature of the kneaded material and the rotor rotation speed.

[0014] The kneading machine 10 also has a temperature sensor 101 capable of detecting the temperature of the material to be kneaded and a rotation sensor 102 capable of detecting the rotor rotation speed. The temperature of the material to be kneaded can be substituted by the temperature of the kneading chamber. In this embodiment, a sensor that detects the temperature of the kneading chamber is used as the temperature sensor 101.

[0015] The mixer control unit 11 has a control unit 2, a storage unit 3, a display unit 4, and an input device 5. In this embodiment, the mixer control unit 11 is configured by a personal computer.

[0016] The control unit 2 is realized by appropriately combining a processing element such as a CPU, a memory, an interface, software, a storage device, etc. In this embodiment, the control unit 2 has a setting processing unit 21, a data acquisition processing unit 22, a relationship derivation processing unit 23, a tensile strength estimation processing unit 24, a kneading condition control processing unit 25, and a kneading failure determination processing unit 26. Details of each unit will be described later.

[0017] The storage unit 3 is realized by a predetermined storage area of ​​a memory or a storage device. The display unit 4 is, for example, a liquid crystal display, and the input device 5 is, for example, a keyboard or a mouse. The display unit 4 may be configured as a touch panel and may also serve as the input device 5. The display unit 4 and the input device 5 may be configured separately from the kneader control unit 11 and configured to be able to communicate with the kneader control unit 11 via wireless communication or the like. In this case, the display unit 4 or the input device 5 may be configured as a mobile terminal such as a tablet or a smartphone.

[0018] (Materials to be mixed) Although details will be described later, this embodiment formulates a process in which, as the kneading proceeds, the powdered filler gradually disperses in the resin, which is a fluid material, to form a uniform kneaded mixture. Therefore, this embodiment basically assumes the case in which a resin (polymer) and a powdered filler are mixed together.

[0019] According to the results of the inventors' investigations, it was found that better mixing results could be obtained when a material containing a flame retardant as a main component was used as the filler. In other words, the present invention is particularly effective when a material containing a flame retardant as a main component is used as the filler. Examples of flame retardants include antimony oxide, aluminum hydroxide, magnesium hydroxide, and zinc borate.

[0020] Furthermore, according to the results of investigations by the present inventors, it was found that better kneading results can be obtained when 150 to 300 parts by mass of filler is used per 100 parts by mass of resin (plastic material). In other words, the present invention is particularly effective when 150 to 300 parts by mass of filler is used per 100 parts by mass of resin.

[0021] The materials used for kneading may contain a cross-linking aid such as trimethylolpropane acrylate (TMPT).

[0022] (Parameters that serve as indicators of the progress of kneading) As a result of investigations, the inventors of the present invention have found that there is a very strong correlation between the progress of kneading and the tensile strength of the kneaded product. For example, when kneading is not progressing, the resin and powder (filler) are mixed in a mottled state, resulting in a low tensile strength of the kneaded product. Furthermore, as kneading progresses, the powder (filler) is crushed into smaller pieces, increasing the contact area between the powder (filler) and the resin, and increasing the tensile strength of the kneaded product. When the powder (filler) is completely and uniformly dispersed in the resin through kneading, the tensile strength reaches its maximum value and saturates. Therefore, in this embodiment, the tensile strength of the kneaded product is used as a parameter that serves as an indicator of the progress of kneading.

[0023] As shown in Figure 2, the kneading process can be divided into two stages: a mixing process and a dispersion process. In the mixing process, after preheating the kneader 10, only the resin (polymer) is added and melted. Then, powdered filler is added in two batches and stirred until a predetermined temperature or time is reached, and the resin and filler are integrated. In the subsequent dispersion process, the mixture is kneaded until it becomes uniform. The filler is then finely crushed and dispersed into the resin, resulting in a uniform distribution of the filler within the resin.

[0024] In this embodiment, the progress of kneading in the dispersion process (that is, how uniformly the filler is dispersed in the resin) in the above two-stage process is estimated from the change in tensile strength of the kneaded product.

[0025] (Formulation of tensile strength of kneaded material) The inventors have formulated the tensile strength of a kneaded material based on thermo-fluid dynamics and structural mechanics. More specifically, in this embodiment, the tensile strength S is calculated by the formula (1) shown in [Mathematical Expression 1]. The derivation of this formula (1) will be described below.

[0026]

number

[0027] During the dispersion process, the domain size L of the filler-rich phase is reduced by the force F applied by the fluid (resin). Therefore, the amount of reduction in the filler domain size ΔL is assumed to be proportional to the force F applied by the fluid. The filler-rich phase refers to a region containing 10% or more of filler (metal powder), and can be obtained by analysis such as EDX. The domain size L of the filler-rich phase is the characteristic length of the filler-rich phase, for example, the maximum width of the filler-rich phase. The amount of reduction in the filler domain size ΔL refers to the amount of reduction in the domain size L per kneading time Δt.

[0028] Here, it is known that the force F is proportional to the product of the shear stress τ and the square of the domain size L. The shear stress τ is expressed as the product of the material viscosity η and the shear rate γ. As the kneading progresses, the domain size L decreases, but there is a limit to how small the domain size L can be, and there is a minimum domain size L. min To summarize the above, the change in domain size dL(t) / dt can be expressed by equation (2) shown in [Mathematical Expression 2].

[0029]

number

[0030] Here, the tensile strength S of the kneaded product is determined by the surface area (L2 is proportional to the volume of the domain (L 3 Then, as shown in the following equation (3), the tensile strength S of the kneaded material is inversely proportional to the domain size L(t), where a is a constant. S(t)=a / {L(t)} (3) As shown in the above formula (3), the more uniformly the filler is distributed and dispersed, and the smaller the domain size, the greater the tensile strength S of the kneaded product. min The tensile strength S of the kneaded material when max Then, the relationship of the following equation (4) is obtained. S max =a / L min ···(4) By substituting the relationship between these equations (3) and (4) into the above equation (2), we obtain equation (5) shown in [Mathematical formula 3].

[0031]

number

[0032] Here, the material viscosity η in the above equation (5) is expressed by equation (6) shown in [Equation 4]. When calculating the material viscosity η, the power law is used, taking into account the non-Newtonian nature of the material flow. Furthermore, the relationship between the shear rate γ and the rotor rotation speed can be expressed by equation (7) shown in [Equation 5]. The shear rate coefficient k in equation (7) is a coefficient that depends on the shape of the kneading machine 10 (shapes of the kneading chamber and rotor, clearance between the kneading chamber and rotor, etc.), and can be determined in advance by conducting experiments.

[0033]

number

[0034]

number

[0035] Substituting these equations (6) and (7) into the above equation (5) and rearranging, we obtain equation (1) shown in [Mathematical formula 6].

[0036]

number

[0037] The coefficient A in the above formula (1) is determined in advance by carrying out test production of a kneaded product under different kneading conditions, and performing fitting using the various data obtained. In this case, the viscosity constant η0, temperature coefficient α, and power exponent n can be obtained by measuring the viscosity of the kneaded product using a capillary rheometer or the like (the power exponent n may be a fixed value based on experimentation or experience). The temperature T of the kneaded product may be obtained by actual measurement, or by solving the equations of thermo-fluid dynamics. The tensile strength S of the kneaded product can be obtained by taking out a portion of the kneaded product, forming it into a sheet, and conducting a tensile test. The largest tensile strength S obtained after sufficient kneading is called the maximum tensile strength S. max This becomes:

[0038] By determining the coefficient A in advance through fitting, it becomes possible to use the above formula (1) to determine the current tensile strength S of the kneaded material based on the actual measured values ​​of the rotor rotation speed N and the temperature T of the kneaded material, and the initial value of the tensile strength S, and to estimate the progress of kneading.

[0039] FIG. 3 is a graph showing both the measured values ​​of tensile strength S (black circles) and the calculated values ​​of tensile strength S (solid line) obtained from the above formula (1). In the example of FIG. 3, 100 parts by mass of ethylene vinyl acetate was used as the resin, and 200 parts by mass of magnesium hydroxide was used as the filler. The kneader 10 was a small kneader with a mixing capacity of 6 liters and a two-blade rotor. During kneading, the resin alone was first kneaded and melted, and then the filler was added in two batches and pre-mixing was performed. Pre-mixing was terminated when the temperature T of the kneaded product reached 100°C. The rotor rotation speed N was then set to a predetermined value, and kneading was continued until the temperature T of the kneaded product reached 150°C.

[0040] Then, samples of the kneaded material were taken from the kneading chamber when the temperature T of the kneaded material was 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, and 150°C, and the taken samples were pressed into a sheet shape and irradiated with an electron beam at a dose of 7 Mrad to crosslink the polymer.Then, the sheet-shaped samples (1 mm thick) were punched into the shape of a No. 6 dumbbell and a tensile test (tensile speed: 250 mm / min) was carried out, and the tensile strength S was measured.

[0041] As shown in Figure 3, the measured and calculated values ​​of tensile strength S are in good agreement, and it can be said that the tensile strength S can be evaluated with high accuracy using the above formula (1). More specifically, the squared value R of the coefficient of determination (correlation coefficient) that indicates the magnitude of the correlation between the measured and calculated values ​​of tensile strength S is 2 The value of the squared coefficient of determination (correlation coefficient) R for the measured value of tensile strength S is 0.995, which is very large. 2 was 0.598, which was small. From this, it can be said that the present embodiment can evaluate the tensile strength S with higher accuracy than the conventional method. Furthermore, as shown in FIG. 3, the tensile strength S becomes saturated as the kneading progresses, and it can be seen that the progress of the kneading can be estimated depending on how close the tensile strength S is to its maximum value.

[0042] (Setting processing unit 21) Returning to Fig. 1, each part of the control unit 2 will be described in detail. The setting processing unit 21 performs setting processing for making various settings of the mixer control unit 11. The setting processing unit 21 can set information related to various controls, such as the method of data acquisition by the data acquisition processing unit 22 and the setting of the data acquisition date and time. The setting processing unit 21 can also register, update, delete, etc., various pieces of information stored in the memory unit 3. The input device 5 or the like can be used to input various pieces of information.

[0043] (Data acquisition processing unit 22) The data acquisition processing unit 22 performs a test production data acquisition process (see FIG. 5(a)) to acquire various data obtained in test production (sometimes collectively referred to as test production data) and store it in the storage unit 3. The data acquisition processing unit 22 associates the acquired various data for each sample and registers them in the test production database 31. In this embodiment, the data includes kneading condition data 61, which is data on kneading conditions including the rotor rotation speed N; temperature data 62, which is data on temperature including the temperature T of the kneaded material; viscosity data 63, which is data on viscosity including the viscosity constant η0, the temperature coefficient α, the power exponent n, etc.; tensile strength S and its maximum value S max The tensile strength data 64 including the above is acquired by the data acquisition processing unit 22. These various data may be input by the input device 5 or may be input from an external device via a network or the like, and some of the data may be acquired directly from the kneading machine 10. Note that the data acquisition processing unit 22 may receive data other than those mentioned above, and the test production database 31 may contain data other than those mentioned above. Furthermore, the data acquisition processing unit 22 may have a function of presenting missing data among the various data, for example, by displaying missing data on the display 4.

[0044] The data acquisition processing unit 22 also performs a prerequisite data acquisition process (see FIG. 5(c)) that receives data including initial value data 33, target tensile strength data 34, and failure judgment threshold data 35. These data are prerequisites for the tensile strength estimation process and the kneading condition control process, which will be described later, and are therefore sometimes collectively referred to as prerequisite data. Here, the initial value data 33 is data on the set values ​​of the temperature T of the kneaded material and the rotor rotation speed N, and the initial value of the tensile strength S of the kneaded material. The target tensile strength data 34 is data on the target tensile strength Si, which is a preset target value for the time change in the tensile strength S of the kneaded material from the start of kneading, and is used by the kneading condition control processing unit 25, which will be described later. The failure judgment threshold data 35 is data on the failure judgment threshold, which is an allowable value for the deviation ΔS between the tensile strength S and the target tensile strength Si, and is used by the kneading failure judgment processing unit 26, which will be described later, to determine whether kneading has failed.

[0045] (Relationship derivation processing unit 23) The relationship derivation processing unit 23 performs a relationship derivation process (see FIG. 5(b)) to determine the relationship between the kneading conditions and the change in tensile strength S of the kneaded product based on the actual measured values ​​obtained in the test production, i.e., various data registered in the test production database 31.

[0046] More specifically, the relationship derivation processing unit 23 applies each piece of data in the test production database 31 to the above equation (1) to derive the coefficient A in the equation (1). The obtained coefficient A is stored in the storage unit 3 as coefficient data 32.

[0047] (Tensile strength estimation processing unit 24) The tensile strength estimation processing unit 24 performs a tensile strength estimation process (see FIG. 6(a)) to estimate the tensile strength S of the kneaded material at the current time based on the temperature T of the kneaded material detected by the temperature sensor 101 during kneading and the rotor rotation speed N detected by the rotation sensor 102. In the tensile strength estimation process, the tensile strength S of the kneaded material at the current time is calculated in real time according to the above formula (1) using the actual measured values ​​of the temperature T of the kneaded material and the rotor rotation speed N when kneading is actually performed. The actual measured values ​​of the temperature T of the kneaded material and the rotor rotation speed N, together with the time at which the actual measurements were performed (i.e., the kneading time), are stored in the memory unit 3 as actual measurement data 36. The tensile strength S calculated in the tensile strength estimation process is stored in the memory unit 3 together with the kneading time as estimated tensile strength data 37. Note that the "current time" means the time point of the current kneading time t. Furthermore, the measurement intervals of the temperature T of the kneaded material and the rotor rotation speed N, that is, the time intervals for estimating the tensile strength S, may be, for example, 10 seconds or more and 20 seconds or less.

[0048] (Kneading condition control processing unit 25) The kneading condition control processing unit 25 calculates a deviation ΔS between the current target tensile strength Si and the tensile strength S of the kneaded product estimated by the tensile strength estimation processing unit 24 based on a preset target tensile strength Si (stored in the storage unit 3 as target tensile strength data 34 in this embodiment), and performs a kneading condition control process (see FIG. 6(b)) to control the kneading conditions of the kneader 10 so as to reduce the deviation ΔS. The deviation ΔS is the absolute value of the difference between the current tensile strength S obtained by the tensile strength estimation processing unit 24 and the current target tensile strength Si. In this embodiment, the kneading condition control processing unit 25 controls the set values ​​of the temperature T of the kneaded product and the rotor rotation speed N as the kneading conditions.

[0049] In this embodiment, the kneading condition control processing unit 25 determines whether the deviation ΔS is equal to or smaller than a preset deviation threshold value ΔS th If the deviation ΔS is less than the deviation threshold ΔS, the current kneading conditions are maintained. th The kneading conditions of the kneader 10 are controlled so that the deviation ΔS becomes smaller when the deviation ΔS is greater than ΔS. This is because the response when the kneading conditions (the set values ​​of the temperature T of the kneaded material and the rotor rotation speed N) are changed is relatively slow, and therefore, if the kneading conditions are controlled too finely, the tensile strength S of the kneaded material may conversely deviate significantly from the target tensile strength Si. Note that, since the response is particularly slow when the set value of the temperature T of the kneaded material is changed (it takes time for the actual temperature of the kneaded material to become equal to the set value (temperature T)), it is desirable to configure the kneading condition control processing unit 25 so that the set value of the rotor rotation speed N is given priority in control.

[0050] The kneading condition control processor 25 may control the kneading conditions (set values ​​of the temperature T of the kneaded material and the rotor rotation speed N) by PID control. PID control is a control that combines proportional control (P), integral control (I), and differential control (D), and is capable of suppressing vibrations and overshoots of the tensile strength S based on the target tensile strength Si, thereby enabling high-speed, stable control.

[0051] It should be noted that if the set value of the kneaded material temperature T or the set value of the rotor rotation speed N is set too high, it is conceivable that the load on the heater and rotor of the kneader 10 will increase, shortening their lifespan. For this reason, allowable maximum values ​​may be set for the set values ​​of the kneaded material temperature T and the rotor rotation speed N, and only values ​​smaller than the maximum values ​​may be set. In other words, settable numerical ranges may be set in advance for the set values ​​of the kneaded material temperature T and the rotor rotation speed N. The kneading condition control processing unit 25 stores the set values ​​of the kneaded material temperature T and the rotor rotation speed N determined by PID control or the like in the memory unit 3 as set value data 38, and outputs them to the kneader 10 to control the kneader 10.

[0052] In this embodiment, the kneader control unit 11 is provided separately from the kneader 10 and is capable of communicating with each other, but this is not limiting, and the kneader control unit 11 may be provided integrally with the kneader 10. In this case, the kneading condition control processing unit 25 may be configured to directly control the heater and the rotor so that the temperature T of the kneaded material and the rotor rotation speed N reach the set values ​​determined by PID control or the like.

[0053] (Kneading failure determination processing unit 26) The kneading failure determination processing unit 26 performs a kneading failure determination process (see FIG. 8) for determining a kneading failure. In the kneading failure determination process, the kneading failure is determined by comparing the deviation ΔS between the current tensile strength S and the target tensile strength Si with a failure determination threshold previously set as failure determination threshold data 35. In this embodiment, the kneading failure determination processing unit 26 determines a kneading failure when the deviation ΔS remains greater than the previously set failure determination threshold for a predetermined period of time. More specifically, the kneading failure determination processing unit 26 determines that the kneading has failed when the number of times that the deviation ΔS is continuously determined to be greater than the previously set failure determination threshold is equal to or greater than the previously set failure determination count. The failure determination count can be set, for example, in the range of 3 to 10 times. This kneading failure determination process is based on the inventors' finding that if the deviation ΔS remains relatively large for a long period of time, there is a high possibility that the kneaded material will not reach the desired tensile strength (the tensile strength Sg at which kneading is determined to be complete (see FIG. 9)).

[0054] In this embodiment, the failure determination threshold is set to a deviation threshold ΔS th However, the threshold for failure judgment is set to the same value as the deviation threshold ΔS th In this case, the failure determination threshold may be a value different from the deviation threshold ΔS th It is recommended to set it to a value greater than

[0055] Furthermore, when the kneading failure determination processing unit 26 determines that kneading has failed, it issues an alarm (alert) and stops the kneader 10 to stop kneading. There are no particular limitations on the specific method for issuing the alarm, but for example, the alarm may be issued by light or sound, or by sending an email to an administrator or displaying an alarm screen on the display unit 4. The alarm can be stopped by pressing a reset button (not shown) or by sending a predetermined reset signal.

[0056] (Kneading method) Fig. 4 is a flow diagram of the kneading method according to this embodiment. As shown in Fig. 4, first, in step S1, a setting process is performed. In the setting process, for example, setting value data 38 is input from the input device 5 or the like, and the setting processing unit 21 performs various settings according to the input setting value data 38, data update processes associated with the various settings, and the like.

[0057] In this embodiment, prior to kneading, a test production is carried out in which a kneaded product is produced by changing the kneading conditions, and the relationship between the tensile strength S and the kneading conditions is derived based on the results of the test production. First, kneading condition data 61, temperature data 62, viscosity data 63, and tensile strength data 64 obtained in the test production are input as test production data from the input device 5 or the like (step S21).

[0058] In step S2, the control unit 2 determines whether test production data has been input. If the determination in step S2 is No (N), the process returns (returns to step S1). If the determination in step S2 is YES (Y), the process performs test production data acquisition processing in step S3. In the test production data acquisition processing, as shown in FIG. 5(a), in step S31, the data acquisition processing unit 22 receives the kneading condition data 61, temperature data 62, viscosity data 63, and tensile strength data 64 that have been input as test production data, and in step S32, registers each received data in the test production database 31 and stores it in the memory unit 3. Thereafter, the process returns and proceeds to step S4 in FIG. 4.

[0059] In step S4, a relationship derivation process is performed. In the relationship derivation process, as shown in FIG. 5(b), first, in step S41, each piece of data in the test production database 31 is applied to the above formula (1) to perform fitting, and the coefficient A is derived. Then, in step S42, the derived coefficient A is stored in the storage unit 3 as coefficient data 32. Then, the process returns, and proceeds to step S5 in FIG. 4. Note that the above steps S2 to S4 can be omitted if the coefficient A is known.

[0060] Next, when actually performing kneading, first, the initial value data 33, the target tensile strength data 34, and the failure judgment threshold data 35 are input as prerequisite data from the input device 5 or the like (step S22). Then, in step S5, the control unit 2 determines whether the prerequisite data has been input. If the determination in step S2 is No (N), the process returns to step S5 (waits until the prerequisite data is input). If the determination in step S5 is YES (Y), the process proceeds to step S6.

[0061] In step S6, a prerequisite data acquisition process is performed. In the prerequisite data acquisition process, as shown in Fig. 5(c), first, in step S61, the data acquisition processing unit 22 receives the initial value data 33, the target tensile strength data 34, and the failure judgment threshold data 35 input as prerequisite data, and in step S62, stores the received data in the storage unit 3. Note that the prerequisite data may include various data such as the maximum values ​​of the temperature T of the kneaded material and the rotor rotation speed N, the measurement interval, the number of failure judgments, etc. Thereafter, the process returns and proceeds to step S7 in Fig. 4.

[0062] In step S7, a mixing process is performed. The mixing process is a step of mixing and integrating the resin and filler before kneading (see FIG. 2). The control unit 2 preheats the kneader 10 and stirs the charged resin and filler at a predetermined temperature for a predetermined time to integrate the resin and filler. In this embodiment, after only the resin is charged and melted, the filler is charged in two batches. After the mixing process in step S7 is completed, kneading begins, and an initial value of 0 (zero) is assigned to a variable n for determining whether kneading has failed (step S8), and then the process proceeds to step S9.

[0063] In step S9, a tensile strength estimation process is performed. In the tensile strength estimation process, as shown in Fig. 6, first, in step S91, the tensile strength estimation processing unit 24 receives actual measurement data 36, ​​which are actual measurement values ​​of the temperature T and rotor rotation speed N of the kneaded product, from the temperature sensor 101 and the rotation sensor 102 of the kneader 10, and in step S92, stores the received actual measurement data 36 in the memory unit 3 together with the time of actual measurement. Thereafter, in step S93, based on the actual measurement data 36, ​​the tensile strength S of the kneaded product at the current time (at the time when the temperature T and the rotor rotation speed N were actually measured) is calculated using the above formula (1). Thereafter, in step S94, the calculated tensile strength S of the kneaded product is stored in the memory unit 3 as estimated tensile strength data 37 together with the kneading time. Thereafter, the process returns and proceeds to step S10 in Fig. 4.

[0064] In step S10, it is determined whether kneading is completed. In this embodiment, the tensile strength S is a predetermined tensile strength Sg (for example, a maximum tensile strength S max When the value of the kneading temperature reaches or exceeds 99% of the value of the kneading temperature, the kneading is judged to be completed. If the result of the judgment in step S10 is Yes (Y), the kneader is stopped in step S11, and the process is then terminated. If the result of the judgment in step S10 is No (N), the process proceeds to step S12.

[0065] In step S12, the deviation ΔS between the tensile strength S of the kneaded material at the current time and the target tensile strength Si at the current time is calculated. After that, in step S13, a kneading failure determination process is performed. In the kneading failure determination process, as shown in FIG. 7, first, in step S131, the deviation ΔS is compared with a failure determination threshold (here, ΔS th If the determination in step S131 is No (N), 0 (zero) is substituted for the variable n (variable n is reset) in step S132, and then the process returns to step S14 in FIG. 4. If the determination in step S131 is Yes (Y), the variable n is incremented in step S133, and the variable n is set to the preset failure determination count n in step S134. th It is determined whether the value is greater than the specified value. If the determination in step S134 is No (N), the process returns and proceeds to step S14 in FIG. 4. If the determination in step S134 is Yes (Y), it is determined that mixing has failed in step S135, an alarm is issued in step S136, and then the mixer 10 is stopped and the process is terminated (interrupted) in step S137. The alarm can be stopped by pressing a reset button (not shown) or by sending a predetermined reset signal.

[0066] In step S14, a kneading condition control process is performed. In the kneading condition control process, as shown in FIG. 8, first, in step S141, the current deviation ΔS is compared with the deviation threshold value ΔS thIf the determination in step S141 is Yes (Y), then in step S142, the set value of the temperature T of the kneaded material and the set value of the rotor rotation speed N are determined by PID control or the like according to the deviation ΔS, and are stored in the memory unit 3 as set value data 38, and then the process proceeds to step S144. If the determination in step S141 is No (N), then in step S143, the current set value of the temperature T of the kneaded material and the set value of the rotor rotation speed N are stored in the memory unit 3 as set value data 38, and then the process proceeds to step S144. In step S144, the set value data 38 is output to the kneader 10, and each set value of the kneader 10 is controlled. Then, the process returns to step S9 in FIG. 4.

[0067] (Example of target tensile strength Si and tensile strength S) FIG. 9 is a graph showing an example of setting the target tensile strength Si (dashed line) and the time change in the tensile strength S of the kneaded product when this setting example is used (solid line). As shown in FIG. 9, the tensile strength S of the kneaded product calculated based on the actually measured temperature T of the kneaded product and the rotor rotation speed N closely follows the target tensile strength Si, and it can be seen that kneading is performed efficiently. The graph of the target tensile strength Si in FIG. 9 corresponds to target tensile strength data 34. The graph of the time change in the tensile strength S of the kneaded product in FIG. 9 corresponds to estimated tensile strength data 37.

[0068] (Actions and Effects of the Embodiments) As described above, the kneading device 1 according to this embodiment includes a tensile strength estimation processing unit 24 that estimates the tensile strength S of the kneaded material at the current time (the time when the temperature T and the rotor rotation speed N are detected) based on the temperature T of the kneaded material detected by the temperature sensor 101 and the rotor rotation speed N detected by the rotation sensor 102, and a kneading condition control processing unit 25 that calculates the deviation ΔS between the current target tensile strength Si and the current tensile strength S of the kneaded material estimated by the tensile strength estimation processing unit 24 based on a predetermined target tensile strength Si, and controls the kneading conditions of the kneader 10 so as to reduce the deviation ΔS.

[0069] This makes it possible to control the kneading conditions so that the change over time in the tensile strength S of the kneaded product (that is, the progress of kneading) becomes a desired change, and it becomes possible to suppress kneading failures.

[0070] (Variation) Although not mentioned in the above embodiment, a plurality of patterns of time-dependent changes in the target tensile strength Si may be stored as the target tensile strength data 34, and the user may select which pattern to use. Also, the time-dependent changes in the target tensile strength Si may be automatically generated by appropriately setting conditions such as the type of resin and the kneading time.

[0071] The mixer control unit 11 may further include a display control unit capable of displaying each piece of data, such as actual measurement data 36, ​​estimated tensile strength data 37, and set value data 38, on the display 4. In this case, the display control unit may be configured to display the target tensile strength data 34 and the estimated tensile strength data 37 together, as shown in Fig. 9, for example.

[0072] Furthermore, in the above embodiment, the kneader control unit 11 is a personal computer, but the present invention is not limited to this. For example, the kneader control unit 11 may be configured as a network device such as a server. In this case, the kneader control unit 11 transmits and receives data to and from the kneader 10 via the network. Also, for example, a terminal for controlling the kneader 10 may be provided, and communication may be performed between the terminal and the kneader control unit 11 via the network. In this case, the terminal acquires actual measurement values ​​from the kneader 10 and controls the kneader 10 based on the setting values ​​received from the kneader control unit 11.

[0073] The number of kneaders 10 controlled by the kneader control unit 11 is not limited to one, and one kneader control unit 11 may be configured to control a plurality of kneaders 10.

[0074] Furthermore, in the above embodiment, the case where the mixer control unit 11 is configured by one personal computer or the like has been described, but this is not limiting, and for example, some of the functions of the mixer control unit 11 may be installed in another personal computer, etc. In other words, the mixer control unit 11 does not need to be configured by one piece of hardware, and may be configured by multiple pieces of hardware.

[0075] In the above embodiment, the deviation threshold value ΔS th is set to a constant value, but is not limited to this, and the deviation threshold value ΔS may be set to change depending on the kneading time t. th For example, there may be a case where the variation in kneading is large at the beginning of kneading, and kneading is judged to have failed even though it has not failed. th is set to a relatively large value (for example, the deviation threshold value ΔS when the kneading is stable (for example, when the tensile strength S of the kneaded material is 80% or more of the tensile strength Sg at which kneading is judged to be completed) th By setting the value larger than , such a problem can be prevented.

[0076] In the above embodiment, the number of failure determinations n th However, the number of failure judgments n is set to a constant value, and is not limited to this. th The number of failure judgments in the initial stage of kneading n may be set. th is set to a relatively large value (for example, the number of failure judgments n when the kneading is stable (for example, when the tensile strength S of the kneaded material is 80% or more of the tensile strength Sg at which kneading is judged to be completed) is set to a relatively large value (for example, when the tensile strength S of the kneaded material is 80% or more of the tensile strength Sg at which kneading is judged to be completed) th By setting the value larger than the above, it is possible to prevent the problem of determining that kneading has failed even though kneading has not failed.

[0077] (Summary of the embodiment) Next, the technical ideas grasped from the above-described embodiments will be described by using the reference numerals and the like in the embodiments. However, the reference numerals and the like in the following description do not limit the components in the claims to the members and the like specifically shown in the embodiments.

[0078] [1] A kneading device (1) for mixing a resin and a filler with a rotor to obtain a kneaded material, comprising: a kneader (10) having a temperature sensor (101) capable of detecting the temperature of the kneaded material and a rotation sensor (102) capable of detecting the rotor rotation speed, which is the rotation speed of the rotor; and a kneader control unit (11) for controlling the kneader (10), wherein the kneader control unit (11) controls the kneader (10) based on the temperature of the kneaded material detected by the temperature sensor (101) and the rotor rotation speed detected by the rotation sensor (102). a tensile strength estimation processing unit (24) that estimates the tensile strength of the kneaded material at the current time based on the rotor rotation speed, and a kneading condition control processing unit (25) that calculates the deviation between the target tensile strength at the current time and the tensile strength of the kneaded material estimated by the tensile strength estimation processing unit (24) based on a target tensile strength that is a preset target value for the change in tensile strength of the kneaded material over time from the start of kneading, and controls the kneading conditions of the kneader (10) so as to reduce the deviation.

[0079] [2] The kneading device (1) described in [1], wherein the kneading condition control processing unit (25) maintains the current kneading conditions when the deviation is equal to or less than a preset deviation threshold, and controls the kneading conditions of the kneader (10) so as to reduce the deviation when the deviation is greater than the deviation threshold.

[0080] [3] The kneading device (1) according to [1], wherein the tensile strength estimation processing unit (24) estimates the tensile strength of the kneaded material using equation (1) shown in [Mathematical Expression 7].

[0081]

number

[0082] [4] The kneading device (1) according to [1], wherein the kneading machine (10) is configured to be able to set the temperature of the kneaded material and the rotor rotation speed, and the kneading condition control processing unit (25) controls the set values ​​of the temperature of the kneaded material and the rotor rotation speed as the kneading conditions.

[0083] [5] The kneading device (1) according to [1], wherein the kneading condition control processing unit (25) controls the kneading conditions by PID control.

[0084] [6] The kneading machine control unit (11) has a kneading failure determination processing unit (26) that determines whether kneading has failed, and the kneading failure determination processing unit (26) determines whether kneading has failed when the deviation remains greater than a preset failure determination threshold for a predetermined period of time. The kneading device (1) described in [1].

[0085] [7] A kneading method for mixing a resin and a filler with a rotor to obtain a kneaded product, comprising: using a kneader (10) having a temperature sensor (101) capable of detecting the temperature of the kneaded product and a rotation sensor (102) capable of detecting the rotor rotation speed, which is the rotation speed of the rotor; estimating the tensile strength of the kneaded product at the current time based on the temperature of the kneaded product detected by the temperature sensor (101) and the rotor rotation speed detected by the rotation sensor (102); determining the deviation between the target tensile strength at the current time and the estimated tensile strength of the kneaded product based on a target tensile strength, which is a preset target value for the time change in the tensile strength of the kneaded product from the start of kneading; and controlling the kneading conditions of the kneader (10) so as to reduce the deviation.

[0086] (Addendum) Although the embodiments of the present invention have been described above, the invention according to the claims is not limited to the above-described embodiments. It should be noted that not all of the combinations of features described in the embodiments are necessarily essential to the means for solving the problems of the invention. Furthermore, the present invention can be appropriately modified and implemented within the scope of its spirit. [Explanation of symbols]

[0087] 1...Kneading device 10...Kneading machine 101...Temperature sensor 102...Rotation sensor 11...Kneader control unit 2...Control unit 21...Settings processing unit 22...Data acquisition processing unit 23...Relationship derivation processing unit 24...Tensile strength estimation processing section 25...Kneading condition control processing section 26...Kneading failure determination processing unit

Claims

1. A kneading device that mixes a resin and a filler with a rotor to obtain a kneaded product, a kneading machine having a temperature sensor capable of detecting the temperature of the kneaded material and a rotation sensor capable of detecting a rotor rotation speed, which is the rotation speed of the rotor; a mixer control unit that controls the mixer, The kneading machine control unit a tensile strength estimation processing unit that estimates a current tensile strength of the kneaded material based on the temperature of the kneaded material detected by the temperature sensor and the rotor rotation speed detected by the rotation sensor; a kneading condition control processing unit that calculates a deviation between a current target tensile strength and a current tensile strength of the kneaded material estimated by the tensile strength estimation processing unit based on a preset target tensile strength, which is a target value of a time change in the tensile strength of the kneaded material from the start of kneading, and controls the kneading conditions of the kneader so as to reduce the deviation. Kneading equipment.

2. the kneading condition control processing unit maintains the current kneading conditions when the deviation is equal to or smaller than a preset deviation threshold, and controls the kneading conditions of the kneader when the deviation is greater than the deviation threshold so as to reduce the deviation. The kneading device according to claim 1 .

3. The tensile strength estimation processing unit estimates the tensile strength of the kneaded material using equation (1) shown in [Mathematical Expression 1]. [Equation 1] The kneading device according to claim 1 .

4. the kneader is configured to be able to set a temperature of the kneaded material and a rotor rotation speed, the kneading condition control processing unit controls set values ​​of the temperature of the kneaded material and the rotor rotation speed as the kneading conditions; The kneading device according to claim 1 .

5. The kneading condition control processing unit controls the kneading conditions by PID control. The kneading device according to claim 1 .

6. The kneading machine control unit has a kneading failure determination processing unit that determines a kneading failure, the kneading failure determination processing unit determines that the kneading has failed when the state in which the deviation is greater than a preset failure determination threshold continues for a predetermined period of time. The kneading device according to claim 1 .

7. A kneading method for obtaining a kneaded product by mixing a resin and a filler with a rotor, comprising: a kneading machine having a temperature sensor capable of detecting the temperature of the kneaded material and a rotation sensor capable of detecting the rotor rotation speed, which is the rotation speed of the rotor; estimating a current tensile strength of the kneaded material based on the temperature of the kneaded material detected by the temperature sensor and the rotor rotation speed detected by the rotation sensor; based on a target tensile strength which is a preset target value of the change in tensile strength of the kneaded material over time from the start of kneading, a deviation between the target tensile strength at the current time and the estimated tensile strength of the kneaded material at the current time is calculated, and the kneading conditions of the kneader are controlled so as to reduce the deviation. Mixing method.

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