JP2002296097A - Meter of powder and grain - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide inexpensively a meter of powder and grain capable of measuring the power and grain accurately with a simple constitution. SOLUTION: Weighing errors (Xf(i-1)+...Xf(i-(n-1)) of each batch of the batch number of times (n) prior to this time set beforehand are added to the weighing error (Xf(i)) of the batch (i) of this time, and the sum is divided by the batch number of times (n), to calculate a running mean value (Xt(i)) of the measuring error at the batch (i) of this time. Then, a running mean value (Xt(i-1)+...Xt(i-(m-1)) of the measuring errors of each batch of the data number of times (m) prior to this time set beforehand is added to the quotient, and the sum is divided by the data number of times (m), to calculate a data mean value (Wf1(i)) of the measuring error at the batch (i) of this time, and a measuring set value (Wf(i+1)) of the batch (i+1) of the next time is corrected based on the value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring a granular material, and more particularly, to an apparatus for measuring a granular material for measuring a granular material for each batch.

[0002]

2. Description of the Related Art Conventionally, there is known a weighing device for weighing particles such as resin pellets and resin crushed materials supplied from a supply hopper or the like. Such a weighing device,
Usually, it is provided with a weighing hopper for receiving the granular material and a load cell for measuring the weight of the supplied granular material. Then, while the powder particles falling from the supply hopper are received by the weighing hopper, when the load cell detects that the powder particles received in the weighing hopper has reached a predetermined set amount, the supply from the supply hopper is performed. To stop.

However, in such a weighing device,
Even if the supply is stopped when the granular material reaches a predetermined set amount in the weighing hopper, the granular material in the process of falling is further weighted to the granular material having the set amount. A weighing error results, and accurate weighing is not possible. For this reason, for example, a head correction control for correcting the set amount is performed by predicting that the granules falling during the fall will be weighted.

As such a head correction control, for example, a method of empirically calculating a weighted amount and correcting a set amount based on the empirical value, for example, a method of presetting a weighing target value and a weighing actual measurement value, is used. A moving average of the weighing errors (average of the weighing errors of the past several batches including the weighing error of the current batch) and correcting the set amount by the moving average of the weighing errors, for example, Various methods such as a method of obtaining a correction value by the PID method from the difference between the obtained measurement target value and the actual measurement value and correcting the set amount by the correction value, or a method of using these methods in combination, are employed. .

[0005]

However, even when such a fall correction control is performed, for example, when the set amount is corrected by the moving average value of the weighing error, the weighing error of a specific batch may be affected by disturbance or the like. If the influence is too large, there is a limit to reducing the weighing error, such as the error in the moving average value of several subsequent batches calculated using the weighing error of the specific batch. Improvement in accuracy is desired. On the other hand, in order to realize such high weighing accuracy, a high-precision weighing device is required, so that the cost becomes extremely high.

The present invention has been made in view of such circumstances, and its object is to provide a simple configuration.
An object of the present invention is to provide an inexpensive powder and granule measuring device capable of accurately measuring powder and granules.

[0007]

Means for Solving the Problems To achieve the above object, an invention according to claim 1 is a method for measuring the amount of a granular material supplied from a granular material supply means for each batch. In the weighing device, the weighing device includes correction control means for calculating a weighing set value for each batch, and the correction control means actually weighs in a current batch from a preset weighing target value. Calculating the weighing error generated in the current batch by subtracting the measured actual measurement value, and adding the weighing error of each batch for the preset number of batches before the current time to the weighing error of the current batch. Calculating the sum of the weighing errors in the current batch, and dividing the sum of the weighing errors in the current batch by the number of batches to obtain a moving average of the weighing errors in the current batch. And calculating the moving average of the weighing error in the current batch to the moving average of the weighing error in the current batch, and adding the moving average of the weighing error in each batch for a preset number of data times before the current batch. Calculating the sum of the moving averages of the current batch and the step of calculating the data average of the weighing errors in the current batch by dividing the sum of the moving averages of the weighing errors in the current batch by the number of times of the data. It is characterized by comprising an averaging correction program provided and a weighing setting program for calculating a weighing set value of the next batch based on a data average value of weighing errors in the current batch.

According to such a correction control means, by the processing of the averaging correction program, in the current batch, first, the weighing error of each batch for a preset number of batches before this time is added, By dividing this by the number of batches, the moving average of the weighing error in the current batch is calculated, and then the moving average of the weighing error of each batch for the preset number of data before the current time is calculated. To calculate the sum of the moving average values of the weighing errors in the current batch, and divide this by the number of times of data to calculate the data average value of the weighing errors in the current batch. Is further averaged together with the moving average of the weighing error of each batch for a preset number of data before this time. .

[0009] By the processing of the weighing setting program, the weighing set value of the next batch is calculated based on the data average value obtained by averaging the moving average value of the weighing error.

Therefore, even if the weighing error of a particular batch becomes very large due to disturbance or the like, and the error of the moving average of several subsequent batches calculated using the weighing error of the particular batch becomes large, Since the moving average values are further averaged, the influence of such disturbance can be reduced. Therefore, the granular material can be accurately measured by simple control.
It is possible to provide an inexpensive high-precision powder and particle weighing device.

The invention described in claim 2 is the first invention.
In the invention described in the above, the correction control means, by subtracting the actual measurement value actually measured in the current batch from the preset measurement target value, to calculate a measurement error occurred in the current batch, A step of calculating an integral correction value in the current batch by adding the weighing error of the current batch to the weighing error integrated value of the previous batch and dividing the result by 2; The weighing setting program is characterized in that the weighing setting value of the next batch is calculated based on the integral correction value in the current batch.

According to the processing of the integral correction program, the weighing error of the current batch is averaged together with the integrated value of the weighing error of the previous batch, and then the averaged integrated error is processed by the processing of the weighing setting program. Based on the correction value, a weighing set value for the next batch is calculated.

Therefore, in addition to the correction based on the data average value, the correction based on the integral correction value further provides
The weighing set value for the next batch can be fine-tuned.
Therefore, the granular material can be measured with higher accuracy by simple control, so that a more accurate powder and particle measuring device can be provided at low cost.

[0014] The invention according to claim 3 provides the invention according to claim 1.
In the invention described in or 2, the correction control means includes:
Subtracting the actual measurement value actually weighed in this batch from the preset weighing target value to calculate the weighing error generated in this batch; and Resetting the differential correction value of the current batch, and if the weighing error of the current batch has the same sign as the differential correction value set in the previous batch, Adding the weighing error of the batch to the differential correction value of the previous batch and setting this as the differential correction value of the current batch; and, if there is a weighing error in the current batch, weighing the current batch. Resetting the current differential correction value when the error is opposite to the positive / negative sign of the differential correction value set in the previous batch. Together, the metering configuration program, on the basis of the differential correction value of the current batch, is characterized by calculating a metric set value for the next batch.

According to the processing of such a differential correction program, the weighing error in the current batch is eliminated, or the weighing error in the current batch is changed to a positive or negative sign with respect to the differential correction value set in the previous batch. Unless it is reversed, the weighing error of the current batch is added to the differential correction value of the previous batch, and this is set as the current differential correction value. On the other hand, if the weighing error in the current batch disappears or the weighing error in the current batch reverses the sign of the differential correction value set in the previous batch, the current differential correction value Reset. Next, by the processing of the weighing setting program, the weighing set value of the next batch is calculated based on the current differential correction value.

Therefore, according to the processing of such a differential correction program, when an error occurs due to a sudden change, the error is continuously added as a differential correction value until the error due to the change disappears. The derivative correction value is reflected on the weighing set value of the next batch. Therefore, it is possible to achieve the correction control that quickly responds to the sudden fluctuation, and it is possible to measure the granular material more accurately.

The invention described in claim 4 is the first invention.
4. The weighing setting program according to any one of claims 1 to 3, wherein the weighing setting program corrects the weighing set value of the current batch based on a data average value of weighing errors in the current batch, thereby setting the weighing setting of the next batch. It is characterized in that a value is calculated.

According to such a weighing setting program,
The weighing set value of the next batch is calculated by correcting the weighing set value of the current batch based on the data average of the weighing error in the current batch. Can be set more accurately and reliably based on the data average value of the weighing errors in the batches.

The invention described in claim 5 is the third invention.
In the invention according to the fourth aspect, the weighing setting program corrects the weighing set value of the current batch based on an integral correction value in the current batch and / or a differential correction value in the current batch, It is characterized in that the weighing set value of the next batch is calculated.

According to such a weighing setting program,
The weighing set value of the next batch is calculated by correcting the weighing set value of the next batch and / or the differential correction value of the current batch. Can be set more accurately and reliably based on the integral correction value and / or the differential correction value in the batch.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic structural view showing one embodiment of a powdery and granular material measuring device according to the present invention.

In FIG. 1, the weighing device 1 is configured to be able to weigh powder and granules falling from a supply hopper 2 as powder and granule supply means for each batch. The supply hopper 2 temporarily stores, for example, powder and granular materials transported from a raw material tank (not shown) by pneumatic transportation or the like. Further, a material supply port is formed below the supply hopper 2, and a supply gate 3 for opening and closing the material supply port is provided. The supply gate 3 includes a gate portion 4 that can face the raw material supply port, and a cylinder portion 5 provided above the gate portion 4. The cylinder portion 5 includes a plunger 6 which can move forward and backward, which is connected to the upper end of the gate portion 5, and the plunger 6 advances to close the supply gate 3.
The gate section 5 closes the material supply port, and the retreat of the plunger 6 causes the supply gate 3 to open, so that the gate section 5 opens the material supply port.

The weighing device 1 includes a weighing hopper 7 for receiving the granular material, and a load cell 8 supporting the weighing hopper 7 and serving as a weight detecting means for weighing the granular material.
And a discharge gate 9.

The weighing hopper 7 has a container shape with a lower part formed in a funnel shape, and has a material receiving opening for receiving a granular material falling from the supply hopper 2 at an upper end thereof. At the lower end, a raw material discharge port for discharging the powder is formed.

The load cell 8 is configured to support the weighing hopper 7 and measure the weight of the granular material received in the weighing hopper 7. Is weighed by the load cell 8 with the weight of the tare (weighing hopper 7) canceled.

The discharge gate 9 has a gate portion 10 which can face the raw material discharge port, and a cylinder portion 11 provided below the gate portion 10. The cylinder portion 11 is a plunger 1 that is movable forward and backward and is connected to a lower portion of the gate portion 10.
The closing operation of the discharge gate 9 is performed by the advance of the plunger 12, the gate section 10 closes the raw material discharge port, and the opening operation of the discharge gate 9 is performed by the retreat of the plunger 12. The gate section 10 is configured to open the raw material discharge port.

In the measuring device 1, the cylinder section 6 of the supply gate 3, the load cell 8 and the cylinder section 11 of the discharge gate 9 are connected to the CPU 13 as correction control means. The CPU 13 stores various programs such as a weighing processing program for executing a weighing operation, an averaging correction program for correcting a weighing error described below, an integral correction program, a differential correction program, and a weighing setting program. ROM14, and
A RAM 15 and the like for storing temporary numerical values for executing various programs are provided.

When a predetermined set amount (measurement set value) of the granular material is measured by the measuring device 1, C
According to the weighing processing program of the PU 13, first, in this batch, the weighing set value of the granular material to be charged from the supply hopper 2 is set, and then the load cell 8 cancels the tare weight of the weighing hopper 9 to perform the measurement. After the automatic zero point adjustment of the weight is performed, the supply gate 3 is opened. Then, the granular material in the supply hopper 2 is dropped from the raw material supply port into the weighing hopper 7 by its own weight, and gradually accumulates in the weighing hopper 7. On the other hand, the load cell 8 always detects the actual weight (measured measured value) of the powder and granular material put into the weighing hopper 7, and thus the measured measured value of the powder and granular material detected by the load cell 8 is When it is determined that the set weighing value has been set in the batch, the supply gate 3 is closed, and the supply hopper 2
The charging of the powder and granules into the container is terminated. Thus, the granular material supplied from the supply hopper 2 can be measured by the measuring device 1 at a predetermined set amount.

After that, the discharge gate 9 is opened, and the powdery material measured at a predetermined set amount is discharged from the raw material discharge port. Then, the discharge gate 9 is closed again.
The supply gate 3 is opened, and the weighing operation for each batch by the weighing processing program is repeated.

In the measuring device 1, FIG.
As shown in (1), after the weighing operation in each batch is completed (S1), in order to correct the weighing error, an averaging correction program (S2) and an integral correction program (S2).
3) By sequentially executing the differential correction program (S4), the weighing set value of the next batch is set by executing the weighing setting program based on each correction value calculated by executing each of the correction programs. (S
5). Next, each correction program will be described in detail.

In the averaging correction program, as shown in FIG. 2, first, after the data sampling program is executed (S2-1), the data averaging program is executed (S2-2) to execute the processing of the data sampling program. The moving average value of the measurement error obtained by the above is averaged.

FIG. 3 is a flowchart showing the processing of the data sampling program. In this data sampling program, an arbitrary number of weighings (for the number of batches: n) for calculating as a moving average value of the weighing error is set in advance, and the current batch (i) counted from the start of the weighing operation is first set. ) Is the set number of batches (n)
It is determined whether or not this is the case (S1). When the current batch (i) is equal to or more than the batch number (n) (S
1: YES), the value previously set as the batch number (n) is set as it is as the batch number (n) (S2). On the other hand, if the current batch (i) is smaller than the number of batches (n) (S1: NO), the number of the current batch (i) is set as the number of batches (n) ( S3).

More specifically, for example, when the number of batches (n) is set to 4, that is, when the moving average value is calculated based on the weighing of 4 times, 1 is set.
The third batch is smaller than 4 set as the number of batches (n), so in such a case (S
1: NO), the number of the current batches (1 to 3) is set as the number of batches (n).

Next, the actual measurement value (W (i)) actually measured in the current batch (i) is subtracted from the measurement target value (Wp) preset as an initial value,
The weighing error (Xf (i)) generated in the current batch (i) is calculated (S4).

Thereafter, the weighing error (Xf (i)) of the current batch (i) is added to each of the batches (i-1, i-2,.・ ・
i- (n-1)), the measurement error (Xf (i-1), Xf
(I-2)... Xf (i- (n-1))) and add the total (Xfa) of the weighing errors in the current batch (i).
(I)) is calculated (S5), and this is divided by the number of batches (n) to calculate the moving average value (Xt (i)) of the weighing error in the current batch (i) (S6).
Then, the process ends.

More specifically, for example, if the current batch is the tenth batch and the number of batches is set to 4, the weighing error of the tenth batch is replaced by the previous three batch errors.
Batches for the number of times, that is, the ninth batch, the eighth batch,
The weighing error of the seventh batch is added to calculate the total weighing error (S5), and this is divided by 4 (S6) to obtain 1
The moving average value of the measurement error in the 0th batch is calculated.

Then, a data averaging program is executed. FIG. 4 is a flowchart showing the processing of the data averaging program. In this data averaging program, an arbitrary number of data (m) for calculating as a data average value
First, it is determined whether or not the current batch (i) counted from the start of the weighing operation is equal to or more than the set number of data (m) (S1).
If the current batch (i) is equal to or more than the data count (m) (S1: YES), the value previously set as the data count (m) is set as it is as the data count (m). Is performed (S2). On the other hand, this batch (i)
Is smaller than the number of data times (m) (S1: N
In O), the number of the current batch (i) is set as the number of data times (m) (S3).

More specifically, for example, when the number of data (m) is 4, that is, when the average value of the data is set to be calculated based on the moving average value of 4 times, 1 to 3 Up to the batch, the number of data times (m)
In such a case (S1: NO), the number of data (m) is set as
The number of the current batch (1 to 3) is set.

Next, the moving average value (Xt (i)) of the weighing error calculated in the current batch (i) is added to the batch (i-1) of a predetermined number of data times (m) before this time. , I-2,... I- (m-1)) moving average values (Xt (i-1), Xt (i-2).
Xt (i- (m-1))) and the sum of the moving average values of the weighing errors in the current batch (i) (Wfa
(I)) is calculated (S4), and the result is divided by the number of times (m) to calculate a data average value (Wf1 (i)) of the weighing error in the current batch (i) (S5).
The process ends.

More specifically, for example, if the current batch is the tenth batch and the data count is set to 4, the moving average value of the weighing error of the tenth batch is added to the previous moving average value. 3 batches, ie 9th batch,
The moving average values of the weighing errors of the 8th and 7th batches are added to calculate the sum of the moving average values of the weighing errors (S4).
By dividing this by 4 (S5), the data average value of the measurement error in the 10th batch is calculated.

FIG. 5 is a flowchart showing the processing of the integral correction program. In this integral correction program, first,
The actual measurement value (W (i)) actually measured in the current batch (i) is subtracted from the measurement target value (Wp) set in advance as an initial value, and a measurement error generated in the current batch (i) is obtained. (Ws (i)) is calculated (S1). Next, it is determined whether or not the current batch (i) is larger than 1 (S2). When the current batch (i) is larger than 1 (S2: YES), that is, when the current batch (i) is 2
If it is after the batch, the weighing error (Ws
(I)) is added to the weighing error integrated value (Wsa (i-1)) of the previous batch (i-1), and this is set as the current weighing error integrated value (Wsa (i)) ( S3), and when the current batch (i) is not larger than 1 (S3)
2: NO), that is, if the current batch (i) is the first batch, the weighing error (Ws (i)) is doubled, and this is multiplied by the current weighing error integrated value (Wsa (i). )) (S4). Thereafter, each process (S3 and S3)
4) This time the measurement error integrated value (Wsa
By dividing (i)) by 2, the integral correction value (Wf2 (i)) in the current batch (i) is calculated (S5).
The process ends.

The weighing error integrated value (Wsa) is the integrated value of the weighing error (Ws) for each batch from the first batch (first batch) to the corresponding batch.

More specifically, for example, if this time is the 10th batch, first, the measurement error generated in the 10th batch is calculated (S1), and then the measurement error of the 10th batch is calculated. The weighing error integrated value of the tenth batch is added to the weighing error integrated value of the ninth batch, and this is set as the weighing error integrated value of the tenth batch (S2: YES, S3). By dividing by (S4),
The integral correction value in the tenth batch is calculated (S
5).

FIG. 6 is a flowchart showing the processing of the differential correction program. In this differential correction program, first,
The actual measurement value (W (i)) actually measured in the current batch (i) is subtracted from the measurement target value (Wp) set in advance as an initial value, and a measurement error generated in the current batch (i) is obtained. (Ws (i)) is calculated (S1). Next, the weighing error (Ws (i)) of the current batch (i) is 0.
Is determined (S2). When the weighing error (Ws (i)) of the current batch (i) is 0 (S
2: YES), that is, if there is no error, the differential correction value (Wf3 (i)) of the current batch (i) is reset to 0 (S3), and the process ends. This batch (i)
The weighing error (Ws (i)) is not 0 (S2: N
O), that is, if there is an error, it is determined whether the weighing error (Ws (i)) of the current batch (i) is greater than 0 (S4). If the weighing error (Ws (i)) of the current batch (i) is greater than 0 (S4: YES),
That is, if there is a positive error, the previous batch (i
It is determined whether the differential correction value (Wf3 (i-1)) of (-1) is 0 or more (S5). Previous batch (i-
If the differential correction value (Wf3 (i-1)) of 1) is 0 or more (S5: YES), that is, the previous batch (i-
If the differential correction value (Wf3 (i-1)) of 1) has the same positive or zero value as the weighing error (Ws (i)) of the current batch (i), The weighing error (Ws (i)) of the batch (i) is added to the differential correction value (Wf3 (i-1)) of the previous batch (i-1), and this is added to the differential correction value (Wf3 ( i)) (S6), and the process ends. On the other hand, when the differential correction value (Wf3 (i-1)) of the previous batch (i-1) is smaller than 0 (S5: N
O), that is, the differential correction value (Wf3 (i-1)) of the previous batch (i-1) has a negative value opposite to the weighing error (Ws (i)) of the current batch (i). If you have
The differential correction value (Wf3 (i)) of the current batch (i) is set to 0
(S3), and ends the process.

The weighing error (W) of the current batch (i)
If s (i)) is smaller than 0 (S4: NO), that is, if there is a negative error, the previous batch (i-1)
It is determined whether the differential correction value (Wf3 (i-1)) is equal to or less than 0 (S7). When the differential correction value (Wf3 (i-1)) of the previous batch (i-1) is 0 or less (S
7: YES), that is, the differential correction value (Wf3 (i-1)) of the previous batch (i-1) is changed to the current batch (i).
If the weighing error (Ws (i)) has the same negative or zero value as the weighing error (Ws (i)), the weighing error (Ws (i)) is used as the differential correction value (Wf3) of the previous batch (i-1). (I-1)), which is set as the current differential correction value (Wf3 (i)) (S6), and the process ends. On the other hand, when the differential correction value (Wf3 (i-1)) of the previous batch (i-1) is smaller than 0 (S7: NO), that is, the differential correction value (Wf3 ( If (i-1)) has a positive value opposite to the weighing error (Ws (i)) of the current batch (i), it is set in the previous batch (i-1). The current differential correction value (Wf3 (i)) is reset to 0 (S3), and the process ends.

The differential correction value (Wf3) is set every time a weighing error occurs. While the error is continuously increasing or decreasing, the weighing error (Ws) for each batch is added. This value is reset when the error disappears or when the increase or decrease of the error is reversed.

More specifically, the weighing error in the current batch (i) disappears, or the weighing error (Ws (i)) in the current batch (i) is reduced to the previous batch (i−
Differential correction value (Wf3 (i-1)) set in 1)
As long as the sign does not reverse, the weighing error (Ws (i)) of the current batch (i) is added to the differential correction value (Wf3 (i-1)) of the previous batch (i-1). This is set as the current differential correction value (Wf3 (i)). On the other hand, the weighing error (Ws
(I)) disappears or this batch (i)
If the sign error is inverted from the differential correction value Wf3 (i-1) set in the previous batch (i-1), the current differential correction value (Ws (i)) Wf3
(I)) is reset.

In this correction control, as shown in FIG. 2, the data of the weighing error (Wf1 (i)) of the weighing error in the current batch obtained as described above is obtained by the processing of the weighing setting program. Integral correction value (Wf2
Based on (i)) and the differential correction value (Wf3 (i)), the weighing set value (Wf (i + 1)) of the next batch is calculated and set.

The weighing set value (Wf (i +
More specifically, in the calculation setting of 1)), the data average value (Wf1 (i)) of the measurement error is multiplied by a data average coefficient (Kp) set in advance according to the apparatus conditions and the like, and integration is performed. The correction value (Wf2 (i)) is multiplied by an integral coefficient (Ki) set in advance according to device conditions and the like.
The differential coefficient (K
After multiplying by d), these are added to the weighing set value (Wf (i)) of the current batch.

Thus, the weighing set value (Wf (i + 1)) in the next batch (i + 1) is set.

Then, in this way, the next batch (i
By setting the weighing set value (Wf (i + 1)) of +1),
With simple control, the granular material can be accurately measured, and the accurate granular material measuring device 1 can be provided at low cost.

That is, in this control, by the processing of the averaging correction program, in the current batch (i),
First, batches (i-1, i-2,... I- (n-
1)) measurement error (Xf (i-1), Xf (i-2)
Xf (i- (n-1))) is added to calculate the total (Xfa (i)) of weighing errors in the current batch (i), and divide this by the number of batches (n). Then, the moving average value (Xt (i)) of the weighing error in the current batch (i) is calculated, and then this is added to each batch (i) for a preset number of data (m) before this time.
−1, i−2,..., I− (m−1)), the moving average values of the measurement errors (Xt (i−1), Xt (i−2),.
(I- (m-1))) and the current batch (i)
Of moving average values of weighing errors in Wfa (i)
Is calculated and divided by the number of data times (m) to calculate the data average value (Wf1 (i)) of the weighing error in the current batch (i), that is, in the current batch (i). Moving average of weighing error (Xt
(I)) further includes each batch (i-1, i-2,...) Corresponding to a preset number of data (m) before this time.
i- (m-1)) of the moving average value of the measurement error (Xt (i-
1), Xt (i-2) ... Xt (i- (m-1)))
Averaged with

Therefore, even if the weighing error of a specific batch becomes very large due to the influence of disturbance or the like, and the error of the moving average value of several subsequent batches calculated using the weighing error of the specific batch becomes large, Since the moving average values are further averaged, the influence of such disturbance can be reduced. Therefore, the granular material can be accurately measured by simple control.
It is possible to provide an inexpensive high-precision powder and particle weighing device.

In this control, the weighing error (Ws
(I)) is averaged together with the weighing error integrated value (Wsa (i-1)) of the previous batch (i-1).

Therefore, in addition to the correction based on the data average value (Wf1), the weighing set value (Wf (i + 1)) of the next batch (i + 1) is finely corrected by the correction based on the integral correction value (Wf2). Can be adjusted. Therefore, the granular material can be measured with higher accuracy by simple control, so that a more accurate powder and particle measuring device can be provided at low cost.

Further, in this control, when an error occurs due to a sudden change due to the processing of the differential correction program, the error is continuously added as a differential correction value (Wf3) until the error due to the change disappears. The differential correction value (Wf3) is reflected on the weighing set value (Wf (i + 1)) of the next batch (i + 1). Therefore, it is possible to achieve the correction control that quickly responds to the sudden fluctuation, and it is possible to measure the granular material more accurately.

In this control, the measurement setting value (Wf) of the next batch (i + 1) is set by the measurement setting program.
(I + 1)) is the data average value (Wf1 (i)) of the weighing error in the current batch (i), and the current batch (i)
Is calculated by correcting based on the integral correction value (Wf2 (i)) at the time and the differential correction value (Wf3 (i)) at the current batch (i), so that the weighing set value of the next batch (i + 1) (Wf (i + 1)) is replaced by the average value (Wf1) of the weighing errors in the current batch (i).
(I)), it is possible to set more accurately and reliably based on the integral correction value (Wf2 (i)) and the integral correction value (Wf3 (i)).

In the weighing device 1 of the present embodiment, the powders and granules are put into the weighing hopper 7 by opening and closing the supply gate 3 from the supply hopper 2. The granular material may be fed into the weighing hopper 7 by a known granular material supply means such as a feeder or an electromagnetic feeder. Further, without providing the supply hopper 2, for example, the granular material may be directly input to the measuring hopper 7 from another processing device.

The integral correction program and / or the differential correction program other than the averaging correction program may be appropriately executed depending on the target weighing accuracy.
It may not be necessary in some cases.

[0060]

As described above, according to the first aspect of the present invention, the granular material can be accurately measured by the simple control. It can be provided at low cost.

According to the second aspect of the present invention, the granular material can be measured with higher accuracy by simple control, so that a more accurate powder and particle measuring device can be provided at low cost. be able to.

According to the third aspect of the present invention, it is possible to achieve the correction control promptly responding to a sudden change,
The powder can be measured with higher accuracy.

According to the fourth aspect of the present invention, the weighing set value of the next batch can be set more accurately and reliably based on the data average value of weighing errors in the current batch.

According to the fifth aspect of the invention, the weighing set value of the next batch can be set more accurately and reliably based on the integral correction value and / or the differential correction value of the current batch.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of a granular material weighing device of the present invention.

FIG. 2 is a flowchart showing a process for correcting a weighing error executed after the weighing operation in each batch is completed.

FIG. 3 is a flowchart showing processing of a data sampling program.

FIG. 4 is a flowchart showing processing of a data averaging program.

FIG. 5 is a flowchart showing processing of an integral correction program.

FIG. 6 is a flowchart showing processing of a differential correction program.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Weighing device 2 Supply hopper 7 Weighing hopper 8 Load cell 13 CPU 15 ROM

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F046 AA00 BA02 BB01 CA01 DA06 EA03 4F201 AC01 AC04 AP14 AR15 BA06 BC02 BC12 BC19 BQ04 BQ07 BQ54 BQ57

Claims (5)

[Claims] An apparatus for measuring a granular material supplied from a granular material supply means for each batch, wherein the measuring device is configured to calculate a measurement set value for each batch. A step of calculating a weighing error occurring in the current batch by subtracting the actual measurement value actually measured in the current batch from a preset measurement target value, the correction control means comprising: Calculating the total of the weighing errors in the current batch by adding the weighing errors of each batch for a preset number of batches before the current batch to the weighing errors of the current batch; Calculating a moving average of the weighing errors in the current batch by dividing the total of the weighing errors by the number of batches; and a moving average of the weighing errors in the current batch. Adding the moving average value of the weighing error of each batch for a preset number of data times before the current value to the value to calculate the sum of the moving average values of the weighing errors in the current batch; Calculating the average value of the weighing errors in the current batch by dividing the sum of the moving average values of the weighing errors in the batch by the number of data times, and the data of the weighing errors in the current batch A weighing setting program for calculating a weighing set value for the next batch based on the average value. 2. The method according to claim 1, wherein the correction control means subtracts an actual measurement value actually measured in the current batch from a preset measurement target value to calculate a measurement error generated in the current batch. Calculating the integral correction value in the current batch by adding the weighing error of the batch of the previous batch to the integrated value of the weighing error of the previous batch, and dividing the result by 2; 2. The apparatus according to claim 1, wherein the setting program calculates a weighing set value of the next batch based on the integral correction value in the current batch. 3. 3. A step of calculating a weighing error occurring in the current batch by subtracting an actual measurement value actually weighed in the current batch from a preset weighing target value, Resetting the current differential correction value if there is no weighing error in the batch, and if the current batch has a weighing error, the weighing error of the current batch is set to the differential correction value set in the previous batch. Adding the weighing error of the current batch to the differential correction value of the previous batch and setting this as the differential correction value of the current batch, if the positive and negative signs are the same, If there is an error, and if the weighing error of the current batch is opposite to the positive / negative sign of the differential correction value set in the previous batch, reset the current differential correction value. The weighing setting program calculates a weighing set value for the next batch based on the differential correction value for the current batch, the weighing setting program comprising: Weighing device for powder. 4. The weighing setting program calculates the weighing setting value of the next batch by correcting the weighing setting value of the current batch based on the data average value of the weighing error in the current batch. 4. The apparatus for measuring a granular material according to claim 1, wherein: 5. The weighing setting program corrects a weighing set value of the current batch based on an integral correction value in the current batch and / or a differential correction value in the current batch, thereby executing the next batch. The apparatus for measuring a granular material according to claim 3, wherein the measurement setting value is calculated.