Method for calculating control parameters of powder / granular material supply device and powder / granular material supply device

Abstract

To provide a method for calculating a control parameter of a powder / granular material supply device capable of improving supply accuracy in constant feeding of a powder / granular material, and a powder / granular material supply device.SOLUTION: There is provided a method for calculating a control parameter to be used for controlling the discharge amount of a powder / granular material G in a powder / granular material supply device 100 comprising a hopper 11 in which the powder / granular material G is charged and a feeder 12 for discharging the powder / granular material G to the outside of the device. The method comprises: filling step S12 of filling up the feeder 12 with the powder / granular material G without generating a non-filling region therein by conveying the powder / granular material G first charged in an operation initial stage at a predetermined speed in the feeder 12; compacting step S13 of compacting the powder / granular material G in the feeder 12 by conveying the charged powder / granular material G at a speed higher than the predetermined speed in the feeder 12; and parameter calculating step S16 of calculating a control parameter by using the discharge amount of the compacted powder / granular material G.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a method for calculating control parameters of a powder or granular material supplying device and the powder or granular material supplying device. [Background technology]

[0002] Powder and granular material supplying devices, also known as feeders, that supply powder and granular material in fixed quantities are already widely known. This type of powder and granular material supplying device includes a hopper into which the powder and granular material is fed, and a feeder that transports the powder and granular material from the hopper using a screw and discharges it outside the device.

[0003] The fixed-quantity supply of powder or granular material is achieved by controlling the amount of powder or granular material discharged outside the device (discharge mass per hour). Specifically, the discharge amount of powder or granular material is feedback-controlled in accordance with the difference between the discharge amount of powder or granular material obtained by monitoring the discharge mass of powder or granular material and a preset discharge amount. An example of a powder or granular material supply device equipped with a means for performing such control is disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-003898 Summary of the Invention [Problem to be solved by the invention]

[0005] In the powder / granular material supplying device described in Patent Document 1, when powder / granular material is first introduced into the feeder, skill is required to make the powder / granular material flow uniform and ensure stable supply in a short time. Specifically, a state in which there is a gap between the powder / granular material and the screw, or between the powder / granular material and the inner circumferential surface of the feeder, is not considered to be a stable state. Whether or not a gap occurs depends on the operating conditions and procedures of the device.

[0006] Furthermore, when a user uses powder or granular material for the first time, the control parameters used to control the powder or granular material discharge amount must be adjusted. This is because different types of powder or granular material have different characteristics of the system to be controlled, and therefore different optimal control parameters. Adjustment of the control parameters must be performed when a stable supply of powder or granular material is possible. If the control parameters are adjusted in an unstable state, the accuracy of the obtained parameters will be low.

[0007] Adjusting the control parameters requires trial and error, which in itself requires skill. If adjustments are not made by an experienced technician, the accuracy of the control parameters will be low. This deterioration in the accuracy of these control parameters will lead to a decrease in the quantitative supply accuracy of the powder / granular material supply device, which in turn will lead to a loss of powder / granular material.

[0008] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for calculating control parameters for a powder or granular material supplying device, and a powder or granular material supplying device, which can improve the precision of quantitative supply of the powder or granular material supplying device. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, the first invention provides a method for calculating control parameters for a powdered or granular material supplying device, which is a method for calculating control parameters used to control the discharge amount of powdered or granular material in a powdered or granular material supplying device having a hopper into which powdered or granular material is fed and a feeder that transports the powdered or granular material from the hopper using a screw and discharges it outside the device, and includes a filling step in which the powdered or granular material that is fed for the first time at the beginning of operation is filled into the feeder at a predetermined speed without creating any unfilled areas in the feeder, a consolidation step in which the filled powdered or granular material is brought into a consolidating state in the feeder by transporting the filled powdered or granular material through the feeder at a speed faster than the predetermined speed, and a parameter calculation step in which the control parameters are calculated using the discharge amount of the powdered or granular material in the consolidated state.

[0010] In addition, in the method for calculating control parameters of a powder or granular material supplying device according to the second invention, the parameter calculation step calculates a control gain constant using a dead time and a time constant obtained from the time-axis waveform of the discharge amount of the powder or granular material in the compacted state, and further corrects the gain constant using the maximum discharge amount of the powder or granular material in the compacted state.

[0011] Furthermore, a powdered or granular material supplying device according to a third aspect of the present invention is a powdered or granular material supplying device comprising: a hopper into which powdered or granular material is input; a feeder that transports the powdered or granular material from the hopper using a screw and discharges it outside the device; and a controller that controls the discharge amount of the powdered or granular material, wherein the controller has a speed control unit that controls the rotational speed of the screw to transport the powdered or granular material within the feeder; and a parameter calculation unit that calculates a control parameter based on the discharge amount of the powdered or granular material, wherein the speed control unit controls the rotational speed of the screw to a predetermined rotational speed to fill the powdered or granular material within the feeder without creating any unfilled areas, and controls the rotational speed to be faster than the predetermined rotational speed to compact the filled powdered or granular material within the feeder, and the parameter calculation unit calculates the control parameter using the discharge amount of the powdered or granular material in the compacted state.

[0012] Furthermore, in the powdered or granular material supplying device of the fourth invention, the parameter calculation unit calculates a control gain constant using a dead time and a time constant obtained from the time-axis waveform of the discharge amount of the powdered or granular material in the compacted state, and further corrects the gain constant using the maximum discharge amount of the powdered or granular material in the compacted state. [Effects of the Invention]

[0013] As a result of research by the inventors, it was found that in order to stably discharge powder and granular materials from the equipment, in addition to there being no voids, the powder and granular materials must be in a consolidated state inside the feeder. Here, consolidation refers to the behavior of powder and granular materials that reduces their volume due to pressure, without destroying the particles. After further research, the inventors discovered a method to stabilize the flow state and achieve a consolidated state. Based on this, they made it possible to calculate the control parameters as a series of sequences.

[0014] Therefore, according to the method for calculating the control parameters of a powder or granular material supplying device and the powder or granular material supplying device of the present invention, the control parameters are calculated after the powder or granular material is stabilized in a consolidated state, thereby improving the accuracy of the control parameters and thereby improving the quantitative supply accuracy of the powder or granular material supplying device. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a diagram schematically illustrating a configuration of a powder / granular material supplying device according to an embodiment of the present invention. [Figure 2] 4 is a flowchart showing steps of a method for calculating control parameters of the powder / granular material supplying device. FIG. [Figure 3A] 4 is a partial cross-sectional view showing a raw material charging step in the method for calculating the control parameters of the powder / granular material supplying device. FIG. [Figure 3B] 4 is a partial cross-sectional view showing a filling step in the method for calculating the control parameters of the powder / granular material supplying device. FIG. [Figure 3C] 10 is a partial cross-sectional view showing a consolidation step in the method for calculating the control parameters of the powder / granular material supplying device. FIG. [Figure 4] 4 is a flowchart showing the content of a parameter calculation step in the method for calculating control parameters of the powder / granular material supplying device. FIG. [Figure 5] 4 is a diagram showing the content of a parameter calculation step in the calculation method of control parameters for the powder / granular material supplying device. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference characters, and description thereof will not be repeated.

[0017] [Configuration of powder and granular material supply device] First, with reference to FIG. 1, the configuration of a powder or granular material supplying device 100 according to an embodiment of the present invention will be described.

[0018] 1 is a schematic diagram showing the configuration of a powdered or granular material supplying apparatus 100. The powdered or granular material supplying apparatus 100 includes at least a hopper 11 into which powdered or granular material is introduced, a feeder 12 that conveys the powdered or granular material G from the hopper 11 to a discharge section 12b by a screw 12a and discharges it outside the apparatus, and a motor 13 that drives the screw 12a.

[0019] The powder / granular material supplying device 100 further includes a weighing unit 14 that monitors the mass of the powder / granular material supplying device 100, a mass conversion unit 20 that converts the monitored mass of the powder / granular material supplying device 100 into a powder / granular material discharge amount (mass of powder / granular material discharged per unit time), a setting unit 30 that sets the powder / granular material discharge conditions, and a controller 40 that controls the powder / granular material discharge amount. The powder / granular material discharge amount is controlled by PI control using the current value of the monitored powder / granular material discharge amount. The mass conversion unit 20 is included in the controller 40.

[0020] The mass conversion unit 20 converts the mass of the powder / granular material supplying device 100 into a discharge amount. Specifically, the mass conversion unit 20 uses the mass of the powder / granular material supplying device 100 monitored by the weighing unit 14 to determine the discharge amount of powder / granular material from the difference per unit time. The setting unit 30 is equipped with a user interface such as an LCD and operation keys. The user operates these to communicate with the controller 40 and set operating conditions, etc. In the fixed quantity supply operation that is the subject of the present invention, a discharge amount is set as an operating condition (hereinafter, the set discharge amount will be referred to as the set discharge amount Fr).

[0021] The controller 40 includes at least a speed control unit 41 that controls the rotational speed of the motor 13 connected to the screw 12a so that the current value of the powder discharge amount becomes the set discharge amount Fr, a motor drive unit 42 that drives the motor 13 based on a command value from the speed control unit 41, and a clock 43.

[0022] The controller 40 further includes a parameter calculation unit 44 that calculates control parameters, an amount calculation unit 45 that calculates the amount of powder or granular material G required for calculating the parameters, and a storage unit 46.

[0023] The parameter calculation unit 44 calculates a proportional gain Kp and an integral gain Ki as gain constants used in PI control. The parameter calculation unit 44 also calculates a correction coefficient k for correcting the gain constants. The gain constants corrected by the correction coefficient k are referred to as a corrected proportional gain Kp' and a corrected integral gain Ki', respectively. The calculation method for each parameter will be described in detail later.

[0024] The speed control unit 41 performs PI control in response to the deviation between the current powder / granular material discharge amount and the set discharge amount Fr. That is, the speed control unit 41 determines the motor target rotation speed Nt using the sum of the value obtained by multiplying the deviation by a corrected proportional gain Kp' and the value obtained by multiplying the time integral of the deviation by a corrected integral gain Ki', and notifies the motor drive unit 42 of this value.

[0025] The motor drive unit 42 controls the motor so that the rotation speed of the motor becomes the motor target rotation speed Nt. The motor is controlled, for example, by feeding back the sensed motor rotation speed to control the drive voltage. With the above configuration, the powder / granular material G is controlled to be supplied at a fixed amount at the set discharge rate Fr.

[0026] [Method for calculating control parameters for powder and granular material supply equipment] Next, a method for calculating the control parameters will be described with reference to Fig. 2. Fig. 2 is a diagram for explaining a method for calculating the control parameters of the powder or granular material supplying device 100. The calculation of the control parameters is made up of six steps.

[0027] The first to third steps in the first half are steps performed to stabilize the control system prior to acquiring the discharge amount data required to calculate the control parameters. The control system refers to the entire powder / granular material supplying device 100 that constitutes a feedback loop. Of course, the control system includes the powder / granular material G. The above-mentioned fluid state of the powder / granular material G is a factor that inhibits the stability of this control system. Therefore, the first half of the steps stabilizes the fluid state of the powder / granular material G. The second half of the steps, the fourth to sixth steps, are steps to acquire the discharge amount data required to calculate the control parameters after stabilizing the control system, and calculate each parameter using the results.

[0028] The first half of the steps in Fig. 2 will be described below with reference to Fig. 3. Fig. 3A, Fig. 3B and Fig. 3C show the first, second and third steps in Fig. 2, respectively.

[0029] 3A shows the state at the end of the raw material charging step S11 of the first step. This step is the first step at the beginning of operation, when the user charges powder or granular material G into the hopper 11. At this time, an amount of powder or granular material G equal to or greater than the amount necessary to complete all steps in FIG. 2 is charged into the hopper 11. The amount of powder or granular material G required is calculated by the amount calculation unit 45 and indicated to the user by the setting unit 30. The amount calculation unit 45 calculates the amount of powder or granular material G required from the set discharge amount Fr and the operating conditions of each step (motor rotation speed and operating time at that motor rotation speed) stored in advance in the memory unit 46, and displays the calculated amount on the setting unit 30.

[0030] When this process is completed, the powder G in the feeder 12 is simply piled up inside the feeder 12 just below the hopper 11 as shown in the figure. Therefore, irregular gaps exist inside the feeder 12.

[0031] When handling powder or granular material that is prone to bridging (powder clogging) in the hopper 11 or at the supply port to the feeder 12, a stirring mechanism or the like may be provided in the hopper 11 to prevent this.

[0032] 3B shows the state at the end of the second filling step S12. The powder / granular material G is gradually transported through the feeder 12 by the screw 12a and filled so as not to leave any unfilled areas. In other words, the powder / granular material G is filled so as not to leave any gaps between the powder / granular material G and the screw 12a or between the powder / granular material G and the inner circumferential surface of the feeder 12.

[0033] The operating conditions for the screw 12a are to set the rotation speed of the motor 13 at a relatively low speed and to set the operating time as short as possible. The specific operating conditions vary depending on the diameter and length of the screw 12a, the rated rotation speed of the motor 13, etc. However, in general, the rotation speed of the motor 13 is preferably within the range of 10% to 40% of the rated rotation speed of the motor 13.

[0034] The operating time here is the minimum time required to fill the powder / granular material G into the feeder 12 without creating any unfilled areas when the motor 13 is operated at a rotation speed within the aforementioned preferred range in this process, and is preferably in the range of approximately 5 seconds to 50 seconds. This allows the powder / granular material G to be filled into the feeder 12 with the minimum amount of powder / granular material G required. This therefore reduces raw material loss of the powder / granular material G required for calculating the control parameters.

[0035] By setting the rotation speed of the motor 13 to a relatively low speed as described above, the fluidity around the contact point between the powder and granular material G and the screw 12a and the contact point between the powder and granular material G and the inner circumferential surface of the feeder 12 is improved, and the powder and granular material G can be fed to the discharge section 12b of the feeder 12 while gradually filling the gaps. If the screw 12a is rotated at high speed while gaps exist in the feeder 12, the fluidity of the powder and granular material will deteriorate, and the powder and granular material G may not flow from the hopper 11 into the feeder 12. Alternatively, if the powder and granular material G is transported with gaps irregularly present, the powder and granular material G may be discharged with pulsation.

[0036] 3C shows the state after the third step, the consolidation step S13, is completed. In this step, the filled powder / granular material G is brought into a consolidation state within the feeder 12. Here, consolidation refers to the behavior in which the volume of the powder / granular material decreases due to the application of pressure, without destroying the powder / granular particles. Because the powder / granular material is a mixture of solid and gas, applying pressure can reduce the mixture ratio of gas.

[0037] The operating conditions for the screw 12a are to set the rotation speed of the motor 13 to a relatively high speed and to set the operating time to be as short as possible. The specific operating conditions vary depending on the diameter and length of the screw 12a, the rated rotation speed of the motor 13, etc. However, in general, the rotation speed of the motor 13 is preferably within the range of 60% to 100% of the rated rotation speed of the motor 13.

[0038] The operating time here is the minimum time required to create a consolidated state inside the feeder 12 when the motor 13 is operated at a rotation speed within the aforementioned preferred range in this process, and is preferably in the range of approximately 2 seconds to 15 seconds. This allows the feeder 12 to be created in a consolidated state using the minimum amount of powder and granular material G required. This therefore reduces raw material loss of powder and granular material G required for calculating the control parameters. Since some types of powder and granular material G cannot be reused, it is desirable to minimize raw material loss of powder and granular material G as much as possible.

[0039] By setting the rotation speed of the motor 13 to a relatively high speed as described above, the screw 12a can apply a pressure to the powder / granular material G. As a result, as shown in the figure, the inside of the discharge tube 12c from the outlet of the hopper 11 to the discharge section 12b of the feeder 12 becomes a consolidated state. After the powder / granular material G becomes a consolidated state, it is discharged outside the device. The consolidated state reduces fluctuations in the density and fluidity of the powder / granular material G and stabilizes them. Therefore, fluctuations in the discharge amount become smaller and the discharge amount becomes stable.

[0040] Through the above steps, the powder G is brought into a consolidated state within the feeder 12, and the discharge amount can be stabilized. In other words, the control system can be stabilized.

[0041] Referring again to FIG. 2, the latter half of the process, from the fourth to the sixth steps, will be described. The fourth step is a maximum discharge amount measurement step S14. In this step, the maximum discharge amount Fm of the powder / granular material supplying device 100 is measured. Specifically, the discharge amount of powder / granular material when the drive motor 13 of the screw 12a is at the rated rotation speed is obtained. This value is required for calculating the control parameters, as will be described in detail later. Because the powder / granular material G has been in a consolidated state in the previous step and the discharge amount has stabilized, a highly accurate value can be obtained.

[0042] When handling powder or granular material G with a low melting point, the maximum discharge amount Fm may be obtained at a motor rotation speed equal to or lower than the rated rotation speed in order to suppress a rise in temperature of the powder or granular material G or to suppress raw material loss of the powder or granular material G. For example, if the discharge amount is obtained at a rotation speed that is 50% of the rated rotation speed, the maximum discharge amount Fm is obtained by doubling that value.

[0043] The fifth step is a discharge amount waveform measurement step S15. As will be described in detail later, the step response waveform of the discharge amount (the time-axis waveform of the powder / granular material discharge amount in response to a unit step input to the motor) used to calculate the control parameters is obtained without using PI control, i.e., in an open loop state. Here too, since the powder / granular material G has been in a consolidated state in the previous step and the discharge amount has stabilized, a highly accurate waveform can be obtained.

[0044] The sixth step is a parameter calculation step S16, in which control parameters are calculated from the results obtained in the fourth and fifth steps.

[0045] The content of the parameter calculation step S16 will be described below with reference to Fig. 4. Fig. 4 shows the control parameters targeted in this step. Among the gain constants shown in the figure, the proportional gain Kp, integral gain Ki, and a correction coefficient k for correcting these gain constants are targeted. The proportional constant α, also shown in the figure, will be described later.

[0046] The gain constant can be calculated if a physical model of the target control system can be constructed. However, it is difficult to express the behavior of granular materials, such as those used in this invention, using a physical model. In such cases, several methods have been proposed to experimentally determine the gain constant.

[0047] For example, methods for determining a gain constant from a step response waveform of a control system (hereinafter referred to as step response methods) include the Ziegler-Nichols method and the CHR method. Note that the step response waveform in this invention is a time-axis waveform of the powder / granular material discharge amount that responds when a unit step input (a transient input at a predetermined motor rotation speed) is instructed to the motor.

[0048] In the step response method described above, the time constant T and dead time L are read as characteristic values ​​from the step response waveform. Then, the gain constant is calculated using an empirical formula with these characteristic values ​​as variables. In other words, if f(x) and g(x) are functions with x as a variable, then in the Ziegler-Nichols method, for example, they can be expressed as Kp=f(T,L) and Ki=g(L). The read characteristic values ​​are substituted into these empirical formulas to calculate the gain constant.

[0049] With reference to FIG. 5, the procedure for reading characteristic values ​​from a step response waveform will be described. However, the reading procedure described here is an example and is not definitive. First, a time-axis waveform of the powder / granule discharge amount is plotted as the step response waveform. Next, a tangent line is drawn at the inflection point of this waveform, and the dead time L from the origin is found from the intersection (time) of the tangent line with the X-axis. Next, the time from the origin when the powder / granule discharge amount is 63.2% of the final convergence value (K) is found. The value obtained by subtracting the dead time L from this time is the time constant T.

[0050] In addition to the above-mentioned step response methods, there are also other methods such as the Hazebroek and Waerden method, the Wolfe method, and the Chien, Hrones and Reswick method, and any method can be selected depending on the situation.

[0051] Next, the correction coefficient k will be explained. The correction coefficient k corrects the values ​​of the proportional gain Kp and integral gain Ki according to the magnitude of the set discharge amount Fr. For example, if the set discharge amount Fr is small, the gain constant is corrected to be smaller accordingly. This allows the discharge amount to be stabilized quickly, regardless of the set discharge amount Fr.

[0052] The correction coefficient k is calculated as the ratio of the set discharge amount Fr to the maximum discharge amount Fm (k=Fr / Fm). The products of the proportional gain Kp and the integral gain Ki and the correction coefficient k are the modified proportional gain Kp' and the modified integral gain Ki', respectively. In this way, the control parameters used in PI control are calculated.

[0053] Finally, the proportionality constant α will be explained. As described above, the powder or granular material supplying device 100 performs feedback control (PI control) on the powder or granular material discharge amount. Here, in order to further improve the controllability of the powder or granular material discharge amount, the powder or granular material supplying device 100 can also perform two-degree-of-freedom control, which combines feedback control and feedforward control.

[0054] Feedback control determines the control amount according to the deviation between the current value of the powder / granule discharge amount and the set discharge amount Fr. Therefore, immediately after starting operation, the deviation may be large, resulting in an excessive control amount. Therefore, feedforward control is performed only immediately after starting operation. In other words, the speed control unit 41 does not use the current value of the powder / granule discharge amount, but directly instructs the motor drive unit 42 on the target motor rotation speed Nt corresponding to the set discharge amount Fr. Once the motor rotation speed reaches the target motor rotation speed Nt, the control switches to PI control. This makes it possible to achieve both the high target value tracking accuracy of feedback control (PI control) and the fast response speed of feedforward control.

[0055] It is empirically known that the convergence value of the motor rotation speed and the powder discharge amount is proportional. Therefore, if the proportionality constant is α, the target motor rotation speed Nt can be calculated using the set discharge amount Fr as Nt = α × Fr. The proportionality constant α is calculated as the ratio of the rated motor rotation speed Nm to the maximum discharge amount Fm (α = Nm / Fm).

[0056] As described above, the powder / granular material supplying device 100 can derive all control parameters through a series of sequences after stabilizing the discharge rate by bringing the powder / granular material G into a consolidated state. In practice, the user follows the above steps in accordance with instructions from the powder / granular material supplying device 100. This allows the control parameters to be optimized according to the operating environment conditions even for users who are not experienced. As a result, the quantitative supply accuracy of the powder / granular material supplying device 100 can be improved.

[0057] [Example: Maximum emission Fm measurement results] In the conventional method, the measured value of the maximum discharge amount Fm obtained in a sequence that does not include the consolidation step S13 at the beginning of operation had an error of 34% compared to the value measured after a sufficient operating time had passed. In contrast, in the sequence that includes the consolidation step S13 using the method of this embodiment, the measured value of the maximum discharge amount Fm obtained at the beginning of operation had an error of 0.11% compared to the value measured after a sufficient operating time had passed. In other words, the measurement accuracy of the maximum discharge amount Fm at the beginning of operation was significantly improved. [Explanation of symbols]

[0058] G Powder 11 Hopper 12 Feeder 12a screw 12b Discharge section 13 Motor 14 Measuring part 20 Mass conversion unit 30 Setting section 40 Controller 41 Speed ​​control section 42 Motor drive unit 43 Clock 44 Parameter calculation section 45 Quantity calculation section 46 Memory section 100 Powder supply device S11 Raw material input process S12 Filling process S13 Consolidation process S14 Maximum emission measurement process S15 Emission waveform measurement process S16 Parameter calculation process

Claims

1. A method for calculating a control parameter used to control a discharge amount of powder or granular material in a powder or granular material supplying device including a hopper into which powder or granular material is introduced and a feeder that conveys the powder or granular material from the hopper by a screw and discharges it outside the device, the method comprising: a filling step in which the powder or granular material that is initially introduced into the feeder is conveyed at a predetermined speed in the feeder at an early stage of operation, thereby filling the powder or granular material into the feeder without creating any non-filled areas; a consolidation step of conveying the filled powder or granular material through the feeder at a speed higher than the predetermined speed to consolidate the powder or granular material within the feeder; a parameter calculation step of calculating a control parameter using the discharge amount of the powder or granular material in the consolidated state. A method for calculating a control parameter, characterized by:

2. The parameter calculation step A control gain constant is calculated using a dead time and a time constant obtained from a time-axis waveform of the discharge amount of powder and granular material in the consolidated state, and the gain constant is corrected using a maximum discharge amount of powder and granular material in the consolidated state.

2. The method for calculating a control parameter according to claim 1,

3. a hopper into which powder and granular material are fed; a feeder that conveys the powder and granular material from the hopper using a screw and discharges it outside the device; A powder / granular material supplying device including a controller for controlling a discharge amount of powder / granular material, The controller a speed control unit that controls the rotation speed of the screw to convey the powder or granular material within the feeder; a parameter calculation unit that calculates a control parameter based on the discharge amount of powder or granular material, The speed control unit By controlling the rotation speed of the screw to a predetermined rotation speed, the powder or granular material is filled into the feeder without generating any non-filled area, and by controlling the rotation speed to be higher than the predetermined rotation speed, the filled powder or granular material is brought into a consolidated state within the feeder; The parameter calculation unit Calculating a control parameter using the discharge amount of the powder and granular material in the consolidated state. A powder and granular material supplying device characterized by the above.

4. The parameter calculation unit A control gain constant is calculated using a dead time and a time constant obtained from a time-axis waveform of the discharge amount of powder and granular material in the consolidated state, and the gain constant is corrected using a maximum discharge amount of powder and granular material in the consolidated state.

4. The powder / granular material supplying device according to claim 3,

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