JP6087129B2 - Powder supply state monitoring and control device for powder continuous constant flow rate feeder - Google Patents

Description

  By visualizing and displaying the supply state of powder that is continuously supplied, the present invention can reliably check various abnormalities in the supply state of the powder, and the contents, causes, inspections, and countermeasures for each abnormality can be confirmed by the touch panel. The present invention relates to a powder supply state monitoring and control device of a powder continuous quantitative supply machine that can easily check and cope with the above.

  Today, in many processes in various industries, there are many parts where powders are involved. For example, processing such as pulverization, classification, mixing, granulation, and drying, and transportation of intermediates, and operations for supplying powder raw materials and intermediates to these apparatuses are required. In particular, the quality of the supply operation affects the efficiency of the processing apparatus, and if it is severe, the success or failure of the entire process is determined.

  Therefore, the present applicant first detects the powder weight in the upper cylinder of the feeder in the powder continuous constant flow rate feeder, and also detects the rotational speed of the feeder and is proportional to the rotational speed. The obtained powder volume flow rate is obtained, the powder weight per rotation is detected, the apparent specific gravity of the supplied powder is calculated from the powder weight per rotation and preset volume data, Calculate the moving average value of the apparent specific gravity obtained every rotation, further calculate the apparent specific gravity (BD value) from the moving average value of the apparent specific gravity, and calculate the supply amount (PV value) from the apparent specific gravity (BD value). A powder continuous constant flow rate feeder configured to calculate and supply the supply amount (PV value) to PID control of the rotational speed of a motor that drives the feeder via a PID control circuit, a D / A conversion circuit, or the like. Was developed and a patent was obtained (see Patent Document 1).

Japanese Patent No. 3312949

  In the control method of the conventional powder continuous constant flow rate feeder, the powder supply amount (PV value) can be displayed on the touch panel, but the configuration of the feeder etc. is displayed on the touch panel because of the sealed structure. Whether or not the supplied supply amount matches the actual supply amount cannot be verified during operation of the supply device.

  In addition, the powder receiving capacity of the powder receiving feeder for supplying powder to the supplying machine is usually 2.5 to 3 times that of the supplying machine. In this case, if the capacity of the powder receiving feeder is too small, a lower and lower limit weight (LL) alarm is generated. However, the actual capacity shortage of the powder receiving feeder cannot be confirmed by the operator unless a lower and lower limit weight (LL) alarm is generated.

  Furthermore, when the flow path on the powder downstream side of the supply machine is blocked and powder clogging occurs, since the supply machine performs flow rate control, the control device detects that the flow rate of powder is insufficient, In the rotation speed control of the supply machine, the maximum rotation speed will be increased, and the rotary drive motor will be overloaded due to powder clogging, or in the worst case, the attachment inside the supply machine will be damaged. There are difficulties.

  However, in the conventional alarm system in the control device of the feeder, the “upper and lower limit weight (HH) alarm” and “lower and lower limit weight (LL) alarm” as powder weight in the powder receiving feeder are apparently measured every time. There are “apparent specific gravity deviation alarm” when the specific gravity (BD value) is significantly different from the apparent specific gravity measured last time, and “flow deviation alarm” when the actual flow value is significantly different from the set value. The operator cannot understand the cause of the alarm and how to deal with the alarm unless the user knows the control contents of the feeder.

  From such a point of view, the present inventors have conducted extensive studies and trial productions in order to solve the above-described problems, and as a result, PLCs (sequencers) used in conventional control devices for powder continuous constant flow rate feeders. A new check program circuit for actual flow rate measurement is created on the touch panel, and the weight data output from the digital load cell amplifier is used to detect the supply and discharge amount of powder per unit time. From the relationship with the time (sec) measured by the PLC clock signal, the actual flow rate value [actual flow rate value (kg / h) = sampling weight (kg) ÷ supply / discharge time (sec) × 3600], and it was found that the above problems could be solved.

  In addition, while both the feeder and the powder receiving feeder are in operation, the increase in the detected weight of the powder is monitored, so that the powder receiving capacity in the powder receiving feeder [receiving capacity (kg / h) = It was found that the increased weight capacity (kg / h) + supply amount of the feeder (kg / h)] can be calculated and confirmed. In this case, the increased weight capacity (kg / h) can be calculated as [= {upper limit weight value (kg) −lower limit weight value (kg)} × 3600 ÷ measurement time (sec)]. Therefore, if the acceptance capacity is less than the powder supply capacity of the feeder, a new alarm generation circuit is added to the PLC to generate an “acceptance capacity shortage alarm” and its contents, cause, inspection method and countermeasures, etc. Has been displayed on the touch panel, so that the operator can easily cope with it, and it has been found that the above problems can be solved.

  Furthermore, since the feeder constantly monitors the weight of the powder, if the powder is clogged, the weight value decreased during the weight loss detection hardly changes and becomes a constant weight value. When the weight value becomes a constant weight in this way, it is determined that the powder is clogged, a new alarm generation circuit is added to the PLC, and a “powder clogging alarm” is generated, and its contents, cause, and inspection method By displaying the countermeasures and countermeasures on the touch panel, it has been found that the operator can easily cope with such a case, and the problems can be solved.

  Then, using the trend data function of the touch panel in the control device of the feeder, the weight value data of the powder is recorded together with the elapsed time of operating the feeder, and the change state is visualized and displayed as time-series analog data. (See Fig. 2) By displaying the alarm display of the abnormal state and the contents, cause, inspection and countermeasures of the alarm, the operator can immediately understand the behavior of the powder, and trouble countermeasures in case of abnormality It was found that the above problem can be solved effectively.

Therefore, an object of the present invention is to constantly confirm the actual flow rate value of the powder continuously supplied by the powder continuous constant flow rate feeder, and to improve the receiving capacity as the efficiency of receiving the powder in the powder receiving feeder. Appropriateness can be confirmed, and changes in powder weight during operation of the feeder can be visualized and displayed as time-series analog data to detect abnormalities in powder weight and powder clogging. Furthermore, a powder supply state monitoring and control device for a powder continuous constant flow rate supply machine capable of easily confirming and responding to various contents, causes, inspections, and countermeasures by using a touch panel for various abnormalities is provided. There is.

In order to achieve the above object, the powder supply state monitoring and control device of the powder continuous constant flow rate supply device according to claim 1 of the present invention continuously drives the powder by rotating the powder supply board with a motor. While detecting the powder weight of the feeder to be supplied and discharged in a fixed quantity, the rotational speed of the powder supply board is detected to obtain a volumetric flow rate proportional to the rotational speed, and the powder per revolution of the powder supply board is obtained. detecting the weight of the powder weight of each rotation of said powder supply board, to calculate the apparent specific gravity of the feed powder and a volume data preset the feeder, the calculated value of the apparent specific gravity The specific gravity average value (BD value) is calculated from the average value of the apparent specific gravity obtained for each rotation of the supply machine, and the powder supply amount in the supply machine (BD) is calculated from the specific gravity average value (BD value) and the rotational speed ( PV value), the supply amount (PV value) is converted into a PID control circuit, D / A conversion Comprising a control device for a powder continuous constant flow rate supply device configured to PID control the number of rotations of a motor that rotationally drives the powder supply board of the supply device via a circuit ,
The supply / discharge amount of the powder per unit time in the supply machine is detected, the weight of the powder to be sampled is determined in advance , and the powder is actually supplied from the relationship with the time until the powder is supplied / discharged. the actual flow rate value of the powder to be the following equation
Actual flow rate value (kg / h) = weight of sampled powder (kg) ÷ supply / discharge time (sec) x 3600
And means for detection by,
Based on the increase in the detected weight of the detected powder in the feeder , the receiving capacity as the efficiency of receiving the powder in the powder receiving feeder that supplies the powder to the feeder is given by the following equation:
Acceptance capacity (kg / h) = Increased weight capacity (kg / h) + Supply amount of feeder (kg / h)
However, increased weight capacity (kg / h) = [Upper limit weight value-Lower limit weight value (kg)] x 3600 ÷ Measurement time (sec)
And means for detection by,
The weight data of the powder is recorded with the trend data function of the touch panel along with the elapsed time of operation of the feeder, and the change state is visualized and displayed as time-series analog data to show the behavior of the powder. A means for monitoring and displaying an alarm display of an abnormal state and a content, cause, inspection, countermeasure and the like of the alarm is provided.

According to a second aspect of the present invention, there is provided a powder supply state monitoring and control device for continuously supplying a powder at a constant flow rate by rotating a powder supply board with a motor to continuously supply powder supplied from a powder receiving feeder. It consists of a powder continuous constant flow feeder configured to discharge and supply a constant flow to
A load cell for detecting a powder weight in the feeder and transmitting a powder weight signal;
A digital load cell amplifier that outputs a weight data signal that has been digitized by inputting a powder weight signal transmitted by the load cell; and
Based on the weight data output from the digital load cell amplifier and read into the weight data reading circuit, the weight of the powder to be sampled is determined in advance, and the powder is actually measured in relation to the time until the powder is supplied and discharged. There the actual flow rate value supplied, the following equation
Actual flow rate value (kg / h) = weight of sampled powder (kg) ÷ supply / discharge time (sec) x 3600
An actual flow rate calculation circuit to calculate by
The receiving capacity as the efficiency of receiving the powder in the powder receiving feeder that detects the increase in the detected weight of the powder based on the weight data read into the weight data reading circuit and supplies the powder to the feeder is as follows: formula
Acceptance capacity (kg / h) = Increased weight capacity (kg / h) + Supply amount of feeder (kg / h)
However, increased weight capacity (kg / h) = [Upper limit weight value-Lower limit weight value (kg)] x 3600 ÷ Measurement time (sec)
An acceptance capacity calculation circuit to calculate by
A powder clogging detection circuit that constantly monitors the weight of the powder by means of a trend data function of a touch panel to detect abnormal powder weight and clogging of the powder;
Touch panel / alarm display / troubleshooting that displays the alarm status of those abnormal states and the contents, causes, inspections, countermeasures, etc.・ Trend data function circuit,
A pulse sensor for detecting a rotation speed of the feeder and generating a rotation speed signal for obtaining a volumetric flow rate linearly proportional to the rotation speed;
A frequency dividing circuit for frequency-dividing the rotational speed signal transmitted by the pulse sensor and generating a synchronization signal of one rotation pulse for each rotation of the powder supply board for weight measurement;
For each synchronization pulse signal from the frequency dividing circuit, the weight data output by the digital load cell amplifier is read into a weight data reading circuit, and sequentially, one rotation of the powder supply board based on the synchronization signal from the frequency dividing circuit. A weight detection circuit that detects the weight of the powder per rotation using the weight signal obtained in
A specific gravity calculation circuit for calculating the apparent specific gravity of the supplied powder from the powder weight per rotation obtained by the weight detection circuit and the volume data set by the volume data setting circuit;
A specific gravity average value calculation circuit that calculates a moving average value of apparent specific gravity based on a calculation output signal obtained for each rotation of the feeder output from the specific gravity calculation circuit;
An apparent specific gravity switching setting circuit for setting a specific gravity average value (BD value) from a signal indicating the apparent specific gravity output from the specific gravity average value calculation circuit;
A supply amount calculation circuit for calculating a powder supply amount (PV value) in the feeder from a specific gravity average value (BD value) from the apparent specific gravity switching setting circuit,
The supply amount (PV value) PID control circuit from the supply amount calculation circuit, via the D / A conversion circuit, which characterized by being configured the rotational speed of the motor of the feeder to the PID control.

  According to the powder supply state monitoring and control device of the powder continuous constant flow rate supply machine according to the present invention, the actual flow rate value of the supplied powder is detected during operation of the supply machine. The normal operating state can be easily and easily confirmed. In addition, by detecting the powder receiving ability of the powder receiving feeder that supplies the powder to the feeder, it is possible to easily and easily confirm whether the receiving feeder is suitable. Furthermore, by detecting the occurrence of powder clogging in the powder passage of the supply machine, the supply machine can be stopped abnormally, and an overload trip of the electric motor driving the supply machine or an attachment inside the supply machine can be detected. Damage can be prevented quickly. Furthermore, by using the trend data function of the touch panel, the powder weight change state is visualized and stopped as time-series analog data, so that the alarm display of abnormal conditions and the contents, causes, inspections, countermeasures, etc. It can be confirmed easily and simply.

  Moreover, according to the powder supply state monitoring and control device of the powder continuous constant flow rate feeder according to the present invention, for example, “upper upper limit weight (HH) alarm”, “lower lower limit weight” set in the conventional control device. (LL) Alarm, Apparent Specific Gravity Deviation Alarm, Flow Rate Deviation Alarm, etc. can be monitored on the touch panel, and the alarm contents, causes, inspections, and countermeasures on the touch panel. Can be confirmed in an interactive manner, the monitoring function as a powder supply state monitoring and control device can be sufficiently enhanced, and the accuracy and reliability of powder supply can be greatly improved. .

  As for the maintainability of the powder supply state monitoring control device according to the present invention, since the CPU, the I / O unit, and the special unit are independent, it is easy to replace when a failure occurs. Moreover, since all instrumentation used is a general-purpose product, maintenance is easy when a failure occurs. In addition, it is possible to change the capability only by changing the software in the sequencer, and even if it is difficult to achieve accuracy due to the physical properties of the powder, it can be easily handled by changing the software, so the flexibility is high, ratio control and tuning control Can be easily performed. And as long as the CPU memory capacity is available, not only can it be controlled, but display / setting etc. can be performed for all the units with one touch panel, so the control panel can be made compact, and the more the number of units, the lower the cost. The benefits of

It is a control system diagram which comprises the powder supply state monitoring control apparatus of the powder continuous constant flow supply machine concerning the present invention. It is the wave form diagram which visualized and displayed the change state of the powder weight as time-sequential analog data with the touch panel by the trend data function of the touch panel.

  Next, an embodiment of the powder supply state monitoring and control device of the powder continuous constant flow rate feeder according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a control system diagram of a powder supply state monitoring and control device of a powder continuous constant flow rate feeder according to the present invention. In FIG. 1, reference numeral 40 indicates a powder receiving feeder, and a powder continuous constant flow supply machine 41 having the same configuration as that of the above-described embodiment is provided below the powder receiving feeder 40. The supply machine 41 is provided with load cells 42 and 43 for detecting the weight of the powder supplied therein, and the weight signal of the powder detected by the load cells 42 and 43 is provided. Is input to the adder 44 and the powder weight (Wn) converted into a digital numerical value is output.

  Reference numeral 45 denotes a pulse sensor disposed on a drive shaft member that rotationally drives a powder supply board (see FIG. 1) of the supply machine 41, and the pulse sensor 45 supplies powder to the supply machine 41. By detecting the rotation speed [rpm] of the disc, the powder volume flow rate V [l / h] linearly proportional to the rotation speed can be obtained. Reference numeral 46 denotes an inverter motor that rotationally drives the powder supply board of the supply machine 41. Reference numeral 47 denotes a powder supply driving motor provided in the powder receiving feeder 40 for supplying powder from the powder receiving feeder 40 to the feeder 41.

  The powder weight signal obtained by the adder 44 is converted to digital weight data (Wn) via the digital load cell amplifier 50, read into the weight data reading circuit 51, and sent to the weight detection circuit 52. Configured to output. The weight data (Wn) read by the weight data reading circuit 51 is input to the level detection and weight detection start pulse output circuit 53, and is a receiving feeder for supplying powder provided in the front stage of the supply machine 41. Forty drive motors 47 are configured to output an acceptance signal and a weight detection start command signal for starting and stopping thereof, respectively.

  In this embodiment, however, the weight data (Wn) output from the digital load cell amplifier 50 is used to detect the supply / discharge amount of the powder per unit time and determine the weight of the sampling powder in advance. The actual flow value [actual flow rate value (kg / h) = sampling weight from the relationship between the time value (sec) measured by the clock signal of the PLC when the weight value of the supplied and discharged powder is reduced. (Kg) ÷ supply / discharge time (sec) × 3600] is provided.

  Further, in order to monitor the increase in the detected powder weight while both the feeder 41 and the powder receiving feeder 40 are in operation, the powder receiving capacity [receiving capacity (kg / h) in the powder receiving feeder 40 is determined. ) = Increased weight capacity (kg / h) + Supply amount of supply machine (kg / h)] is provided. In this case, the increased weight capacity (kg / h) can be calculated as [= {upper limit weight value (kg) −lower limit weight value (kg)} × 3600 ÷ measurement time (sec)].

  Further, since the feeder 41 constantly monitors the weight of the powder, when the powder is clogged, the weight value decreased during the weight loss detection hardly changes, and the constant weight value is maintained. Therefore, the powder clogging detection circuit 35 that can determine the clogging state of the powder when the weight value becomes constant as described above is provided.

  Then, using the trend data function of the touch panel for controlling the feeder 41, the weight value data of the powder is recorded together with the elapsed time of operating the feeder 41, and the change state is visualized as time-series analog data. Display (see Fig. 2), monitor the behavior of powder, display alarm display of abnormal condition and the contents, cause, inspection and countermeasure of the alarm, touch panel, alarm display, troubleshooting, trend data function circuit 36 is provided.

  Further, the rotational speed signal of the powder supply board of the feeder 41 obtained by the pulse sensor 45 is divided by the frequency dividing circuit 55, and one rotation 1 of the rotary shaft member for measuring the weight ΔW [g]. A pulse synchronization signal is generated and input to the weight (ΔW) detection circuit 52. That is, in this case, the weights W1, W2, W3,..., Wn of the powder for each rotation in the feeder 41 from the load cells 42, 43 are digitalized for each synchronization pulse signal from the frequency divider 55. The weight data is read into the weight data reading circuit 51 through the load cell amplifier 50 and output to the weight (ΔW) detection circuit 52.

  The weight (ΔW) detection circuit 52 uses the weight signal Wn sequentially obtained for each rotation of the feeder 41 based on the synchronization signal from the frequency dividing circuit 55 and subtracts the previous value from the current value to obtain the weight change ΔWn. That is, the powder weight ΔWn [g] per rotation is detected.

ΔW1 = WST-W1
ΔW2 = W1 -W2
ΔW3 = W2 -W3
・
・
ΔWn = Wn-1 -Wn
Here, WST represents the powder weight at the start of reading, and W1, W2, W3,..., Wn represent the powder weight at each rotation after the start.

The detected value ΔWn is the powder weight ΔWn [g] per rotation of the rotating shaft member of the supply machine 41. If ΔV [ml] is the annular passage volume of the supply machine 41, the apparent specific gravity BD of the supply powder is given. [G / ml] is calculated by the specific gravity calculation circuit 54.
BD = ΔWn / ΔV
Is required.

  In the specific gravity comparison calculation circuit 54, the ΔV is a constant value determined by the model and model number of the supply machine 41, set in the volume data setting circuit 30, and input to the specific gravity calculation circuit 54. When ΔWn ≦ 0, data of ΔWn is not sent to the specific gravity calculation circuit 54. Further, when the reset signal is output to the frequency dividing circuit 55, the data of the weight ΔWn read into the weight detection circuit 52 are all cleared, and the weight detection circuit 52 starts again from the powder weight WST at the start of reading. Start reading data.

  Next, the moving average value of the apparent specific gravity, that is, the specific gravity average value BDAV is calculated by the specific gravity average value calculation circuit 56 based on the calculation output signal obtained from the specific gravity calculation circuit 54 for each rotation of the feeder 41. . Taking the case of moving average number (m) = 3 as an example, it is as follows.

(First time) Since there is only one apparent specific gravity BD data, the specific gravity average value BDAV = BD1.
(Second time) Since there are two apparent specific gravity BD data, the specific gravity average value BDAV = (BD1 + BD2) / 2.
(Third) Since there are three apparent specific gravity BD data, the specific gravity average value BDAV = (BD1 + BD2 + BD3) / 3.
・
・
(Nth time) Hereinafter, the specific gravity average value BDAV = (BDn + BDn-1 + BDn-2) / n.

  In this way, the signal BDAV (specific gravity average value) indicating the apparent specific gravity of the powder output from the specific gravity average value calculation circuit 56 is input to the digital indicator 59 and instructed. As described above, after the m-th rotation from the start of rotation of the powder supply board of the feeder 41, the apparent specific gravity is output as an average specific gravity value for m times such as the current value, the previous value, and the previous previous value, and the apparent specific gravity is When the change occurs due to the cause of the error, the change is corrected by 100 / m [%]. Therefore, by selecting m as an optimum value, the responsiveness can be quickened and the accurate apparent specific gravity can be measured.

  The output signal BDAV indicating the apparent specific gravity from the specific gravity average value calculation circuit 56 is configured to be input to the apparent specific gravity (BD value) switching setting circuit 60. In this apparent specific gravity switching setting circuit 60, the BD value corresponding to the apparent specific gravity of the powder from the initial setting device 61 at the start of powder supply of the supplying machine 41 is initialized, and after the rotating of the supplying machine 41, the initial setting device. Instead of the BD value from 61, the BD value from the specific gravity average value calculation circuit 56 is set and input to the supply amount (PV value) calculation circuit 64.

  A specific gravity deviation determination circuit 57 is inserted between the specific gravity calculation circuit 54 and the specific gravity average value calculation circuit 56, and the current value of the specific gravity value obtained from the specific gravity calculation circuit 54 varies significantly from the previous value. In the case (for example, when there is a deviation of ± 20% or more), a specific gravity deviation signal is output and displayed on the specific gravity deviation display unit 58, and it can be visually confirmed that the specific gravity has changed abnormally.

  On the other hand, the supply machine 41 is configured to be rotated by an inverter motor 46 to supply powder. The volume flow rate V [l / h] of the supplied powder is set so as to be linearly proportional to the rotation speed [rpm] of the inverter motor 46. A pulse sensor 45 is attached to the rotating shaft member of the feeder 41. The pulse sensor 45 transmits a pulse signal having a frequency F1 proportional to the volume flow rate V of the powder. The pulse signal from the pulse sensor 45 is converted into an analog voltage by an F / V (frequency / voltage) converter 62 and further converted into a digital signal by an A / D converter 63. In the digital signal output from the A / D converter 63, since the rotation speed [rpm] and the volume flow rate V [l / h] are linearly proportional, if N is the rotation speed and k is a proportional constant, the volume flow rate V Is expressed as a function of kN [l / h].

  Accordingly, the supply amount PV [kg / h] is PV = BD × kN, and the supply amount calculation circuit 64 performs this calculation. The supply amount PV value, which is an output from the supply amount calculation circuit 64, is input to a PID (proportional integral differentiation) control circuit 65 and compared with a flow rate setting value SV set in advance by the flow rate setting circuit 32. The control signal output from the PID control circuit 65 is converted into an analog voltage by the D / A converter 66 and input to the inverter 67. The inverter 67 variably controls the voltage and frequency supplied to the inverter motor 46 of the feeder 41 in accordance with a control signal from the PID control circuit 65, thereby changing the rotation speed of the inverter motor 46 and controlling the amount of powder supplied. PID (proportional integral derivative) control. Thus, as described above, the supply amount PV [kg / h] is obtained by calculating the value of the apparent specific gravity and the rotational speed [rpm], and the driving rotational speed is PID-controlled by an inverter system, so that accuracy and reliability are obtained. High constant flow rate can be realized.

  The output of the A / D converter 63 is converted into a rotation speed [rpm] by a rotation speed conversion circuit 68 and is digitally indicated by a digital indicator 69. The output of the supply amount calculation circuit 64 is input to the payout integration pulse output circuit 70, integrated by the integration counter 71, and the integrated supply amount of powder is digitally displayed by the digital indicator 72. Further, the output of the supply amount calculation circuit 64 is also input to the supply amount display circuit 73, and the supply amount (PV value) is digitally displayed by the digital indicator 74.

  As described above, in the powder continuous constant flow rate feeder according to the present invention, in order to detect the digital weight signal (ΔWn) of the powder per rotation, the weight of the powder in the feeder ( Wn) is measured, then the weight (Wn) is digitally converted, and the change in the digital weight of the powder per revolution (Wn-1 -Wn) is calculated. A digital weight signal (ΔWn) is obtained. Next, a volume amount (ΔV) for each rotation that is determined in advance by the model of the feeder is set. Next, based on the digital weight signal (ΔWn) and the volume amount (ΔV), the calculation of the weight / volume amount (ΔWn / ΔV) is performed for each rotation of the feeder to obtain a calculation output signal (BDn). . Finally, the moving average value (BDAV) is calculated by moving average (ΣBD / m) of the plurality of calculation output signals, and the moving average value (BDAV) is output as a signal indicating the apparent specific gravity of the powder. That is, when calculating the moving average value, m times of movement such as the current value (BDn), the previous value (BDn-1), the previous value (BDn-2) of the calculation output signal obtained every rotation of the feeder. By calculating as an average value {(BDn− (m−1) +... + BDn−2 + BDn−1 + BDn) / m}, an apparent specific gravity measurement result of powder during continuous supply can be obtained. Note that an optimal value is selected as the number m of moving averages so as to satisfy both accuracy and responsiveness.

  In addition, in the present invention, a continuous constant flow rate is accurately and accurately supplied to foods such as carbon black, silica, titanium oxide, pulverized coal, wheat flour, rice flour, and starch, which are generally very difficult to supply at a constant flow rate. In a powder continuous constant flow rate supply machine capable of detecting the weight data (ΔWn) of the powder per rotation of the supply machine, the weight data (ΔWn) is detected by a computing unit according to the model and model number of the supply machine. A division calculation (ΔWn / ΔV) is performed for each rotation of the feeder with the volume data (ΔV) determined for each rotation to obtain a calculation output signal (BDn), and a plurality of the calculation output signals obtained for each rotation are obtained. The moving average value can be calculated and the moving average value can be output as a signal indicating the apparent specific gravity of the powder.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the spirit of the present invention.

30 Volume data setting circuit 32 Flow rate setting circuit 34 Actual flow rate calculation circuit and feeder receiving capacity calculation circuit 35 Powder clogging detection circuit 36 Touch panel / alarm display / troubleshooting / trend data function circuit 40 Powder receiving feeder 41 Constant flow rate feeder 42 43 Load cell 44 Adder 45 Pulse sensor 46 Inverter motor 47 Drive motor for powder supply 50 Digital load cell amplifier 51 Weight data reading circuit 52 Weight detection circuit 53 Level detection and weight detection start pulse output circuit 54 Specific gravity calculation circuit 55 Frequency division circuit 56 Specific gravity average value calculation circuit 57 Specific gravity deviation determination circuit 58 Specific gravity deviation display section 59 Digital indicator 60 Apparent specific gravity switching setting circuit 61 Initial setting device 62 for starting powder supply F / V converter 63 A / D converter 64 Supply amount Calculation circuit 65 PID Control circuit 66 D / A converter 67 Inverter 68 Speed conversion circuit 69 Digital indicator 70 Discharge integration pulse output circuit 71 Integration counter 72 Digital indicator 73 Supply amount display circuit 74 Digital indicator

Claims (2)

The powder supply board is rotated by a motor to detect the powder weight of a feeder that continuously feeds and discharges powder, and the rotation speed of the powder supply board is detected and proportional to the rotation speed. The volume flow rate is obtained, the powder weight per rotation of the powder supply board is detected, and the powder weight per rotation of the powder supply board and the preset volume data of the feeder are obtained. The apparent specific gravity of the supplied powder is calculated, the specific gravity average value (BD value) is calculated from the average value of the apparent specific gravity obtained for each rotation of the feeder from the calculated value of the apparent specific gravity , and this specific gravity average value (BD value) ) and calculates the supply amount of the powder in the feeder from said rotational speed (PV value), the supply amount (PV value) PID control circuit, powder of the feeder via a D / a converter Powder series configured to perform PID control of the number of rotations of a motor that rotationally drives the body supply board Consists of a controller for the continuous flow rate feeder
The supply / discharge amount of the powder per unit time in the supply machine is detected, the weight of the powder to be sampled is determined in advance , and the powder is actually supplied from the relationship with the time until the powder is supplied / discharged. the actual flow rate value of the powder to be the following equation
Actual flow rate value (kg / h) = weight of sampled powder (kg) ÷ supply / discharge time (sec) x 3600
And means for detection by,
Based on the increase in the detected weight of the detected powder in the feeder , the receiving capacity as the efficiency of receiving the powder in the powder receiving feeder that supplies the powder to the feeder is given by the following equation:
Acceptance capacity (kg / h) = Increased weight capacity (kg / h) + Supply amount of feeder (kg / h)
However, increased weight capacity (kg / h) = [Upper limit weight value-Lower limit weight value (kg)] x 3600 ÷ Measurement time (sec)
And means for detection by,
The weight data of the powder is recorded with the trend data function of the touch panel along with the elapsed time of operation of the feeder, and the change state is visualized and displayed as time-series analog data to show the behavior of the powder. A powder supply state monitoring and control device for a powder continuous constant flow rate supply device, characterized in that it is provided with means for monitoring and displaying alarm indications of abnormal conditions and the contents, causes, inspections and countermeasures of the alarms. . It consists of a powder continuous constant flow supply machine configured to rotate and drive the powder supply board by a motor and continuously supply and discharge the powder supplied from the powder receiving feeder.
A load cell for detecting a powder weight in the feeder and transmitting a powder weight signal;
A digital load cell amplifier that outputs a weight data signal that has been digitized by inputting a powder weight signal transmitted by the load cell; and
Based on the weight data output from the digital load cell amplifier and read into the weight data reading circuit, the weight of the powder to be sampled is determined in advance, and the powder is actually measured in relation to the time until the powder is supplied and discharged. There the actual flow rate value supplied, the following equation
Actual flow rate value (kg / h) = weight of sampled powder (kg) ÷ supply / discharge time (sec) x 3600
An actual flow rate calculation circuit to calculate by
The receiving capacity as the efficiency of receiving the powder in the powder receiving feeder that detects the increase in the detected weight of the powder based on the weight data read into the weight data reading circuit and supplies the powder to the feeder is as follows: formula
Acceptance capacity (kg / h) = Increased weight capacity (kg / h) + Supply amount of feeder (kg / h)
However, increased weight capacity (kg / h) = [Upper limit weight value-Lower limit weight value (kg)] x 3600 ÷ Measurement time (sec)
An acceptance capacity calculation circuit to calculate by
A powder clogging detection circuit that constantly monitors the weight of the powder by means of a trend data function of a touch panel to detect abnormal powder weight and clogging of the powder;
Touch panel / alarm display / troubleshooting that displays the alarm status of those abnormal states and the contents, causes, inspections, countermeasures, etc.・ Trend data function circuit,
A pulse sensor for detecting a rotation speed of the feeder and generating a rotation speed signal for obtaining a volumetric flow rate linearly proportional to the rotation speed;
A frequency dividing circuit that divides the rotation speed signal transmitted by the pulse sensor to generate a synchronization signal of one rotation pulse for each rotation of the powder supply board for weight measurement;
For each synchronization pulse signal from the frequency dividing circuit, the weight data output by the digital load cell amplifier is read into a weight data reading circuit, and sequentially, one rotation of the powder supply board based on the synchronization signal from the frequency dividing circuit. A weight detection circuit that detects the weight of the powder per rotation using the weight signal obtained in
A specific gravity calculation circuit for calculating the apparent specific gravity of the supplied powder from the powder weight per rotation obtained by the weight detection circuit and the volume data set by the volume data setting circuit;
A specific gravity average value calculation circuit that calculates a moving average value of apparent specific gravity based on a calculation output signal obtained for each rotation of the feeder output from the specific gravity calculation circuit;
An apparent specific gravity switching setting circuit for setting a specific gravity average value (BD value) from a signal indicating the apparent specific gravity output from the specific gravity average value calculation circuit;
A supply amount calculation circuit for calculating a powder supply amount (PV value) in the feeder from a specific gravity average value (BD value) from the apparent specific gravity switching setting circuit,
Wherein the supply amount of the supply amount calculating circuit (PV value) PID control circuit via a D / A conversion circuit, which characterized by being configured the rotational speed of the motor of the feeder to the PID control powder Powder supply state monitoring and control device for continuous constant flow rate feeder.

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