JP2009180612A - Metering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately determine influence of winds. <P>SOLUTION: A combination metering apparatus 2 is provided with metering hoppers H(n) for weighing materials, a vibration detecting part 26 for detecting extraneous vibration, and a determination part 272. The determination part 272 uses a plurality of calculation values obtained based on metered values W(n, t) obtained by metering with the metering hoppers H(n) and influence of the extraneous vibration detected by the detecting part 26 onto the metered values W(n, t), to determine the existence of the influence of winds onto the metered values W(n, t). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a weighing device, and more particularly to a weighing device that takes into account the influence of disturbances such as vibration and wind.

  The weighing with the weighing device is easily affected by the vibration of the floor where the weighing device is installed (external vibration). For this reason, the measured value measured by the weighing device tends to deviate from the actual value.

  Therefore, conventionally, a technique for correcting the measurement value in consideration of the influence of external vibration has been proposed. Specifically, the weighing device includes a load cell that detects floor vibration, for example, AFV (Anti Floor Vibration). The weighing device corrects the measured value based on the result detected by the load cell. Such a technique is disclosed in, for example, Patent Documents 1 and 2 listed below.

  Further, the weighing hopper opens and closes the gate when discharging the article thrown into the weighing hopper. At this time, wind is generated as the gate is opened and closed, which affects the measurement of the weight of the article. For example, in the combination weighing device, when the weight of an article put into a certain weighing hopper is measured, if the weighing hopper adjacent to the weighing hopper is opened and closed, the weighing value is actually affected by the influence of wind. Will deviate from this value.

In view of this, a technique for correcting the measurement value in consideration of the influence of wind accompanying opening and closing of the measurement hopper has been proposed. Specifically, the weighing device stores the previously detected wind influence in a table. The weighing device corrects the measurement value based on the table. Such a technique is disclosed in, for example, Patent Document 3 listed below.
Japanese Patent Laid-Open No. 7-280634 JP-A-8-114493 JP 2005-69957 A

  However, the technique of Patent Document 3 has a problem in that since the measurement value is corrected in consideration of only the influence of the wind from the weighing hopper, the influence of the wind generated outside the weighing hopper is not taken into consideration.

  Further, since the load cell for detecting floor vibration is built in the weighing device, the floor vibration detection load cell is not exposed to wind. For this reason, the influence of wind cannot be detected in the floor vibration detection load cell.

  The present invention has been made in view of the above-described circumstances, and an object thereof is to appropriately determine the influence of wind in a weighing device.

  A weighing apparatus according to a first invention includes a weighing unit that measures the weight of an article, a detection unit that detects external vibration, and a determination unit. The judgment unit uses the calculated value obtained based on the measurement value measured by the measurement unit and the external vibration detected by the detection unit on the measurement value. Determine.

  According to the measuring device according to the first aspect of the present invention, since the influence of wind on the measurement value is determined in consideration of the influence of external vibration, the influence of the wind on the measurement value can be appropriately determined. Moreover, by determining the presence / absence of wind influence using a plurality of calculated values, it is possible to accurately determine the presence / absence of wind influence even when the measured value changes slowly with a large period.

  A weighing device according to a second aspect of the present invention is the weighing device according to the first aspect of the present invention, wherein when there are no fluctuations in the amount of articles in the same weighing unit and the plurality of calculated values are different, It is determined that there is an influence.

  According to the weighing device according to the second aspect of the present invention, it is easy to compare a plurality of calculated values by setting the same article that does not vary in quantity as a measurement target of the weighing unit. That is, it can be determined that the wind affects the measurement value when a plurality of calculated values are different even though there is no change in the amount of the article. Therefore, the presence or absence of the influence of wind can be determined with high accuracy.

  A weighing device according to a third invention is the weighing device according to the second invention, wherein one of the plurality of calculation values is based on the measurement value at a certain first time and the influence of external vibration. It is obtained. The other calculated values among the plurality of calculated values are obtained based on the measurement value and the influence of external vibration at the second time after a predetermined time has elapsed from the first time. Then, the determination unit determines whether or not there is an influence of wind by comparing another calculated value with one calculated value.

  According to the weighing device according to the third aspect of the present invention, the accuracy of determining the presence or absence of the influence of wind is increased by comparing a plurality of calculated values having different times.

  A weighing device according to a fourth invention is the weighing device according to the third invention, and the predetermined time is different from a mechanical operation cycle of the weighing unit.

  According to the weighing device according to the fourth aspect of the present invention, the accuracy of determining the presence or absence of the influence of wind when the change in the measured value changes gradually with a large period is increased.

  A weighing device according to a fifth aspect of the present invention is the weighing device according to the third or fourth aspect of the present invention, further comprising a storage unit, a calculation unit, and a correction unit. The storage unit stores a difference between each of the other calculated values at a plurality of different second times and one calculated value. The calculation unit obtains the standard deviation from the distribution of the differences using the difference stored in the storage unit. A correction part correct | amends the measurement value obtained by a measurement part using the standard deviation calculated | required by the calculating part, when the determination part determines with the influence of a wind.

  A weighing device according to a sixth invention is a weighing device according to the third or fourth invention, comprising a plurality of weighing units, and combining the measured values measured by the weighing units. In addition, the weighing device further includes a storage unit, a calculation unit, and a correction unit. The storage unit stores a difference between each of the other calculated values at a plurality of different second times and one calculated value. The calculation unit obtains the standard deviation from the distribution of the differences using the difference stored in the storage unit. A correction part correct | amends the target value of the combination calculation of a measured value using the standard deviation calculated | required by the calculating part, when the determination part determines with the influence of a wind.

  According to the weighing device according to the sixth aspect of the invention, the influence of wind can be reflected in the target value by correcting the target value of the combination calculation by the correction unit. Therefore, the articles after combination can be weighed without falling below the target value before correction.

  A weighing device according to a seventh invention is the weighing device according to the first invention, wherein the determination unit is detected by the detection unit at different times when there is no change in the amount of the article in the same weighing unit. It is determined that there is an influence of wind when a plurality of calculated values excluding the influence of the external vibration obtained based on the measurement value and the external vibration are different from each other when the variation of the plurality of external vibrations is within a predetermined range.

  A weighing device according to an eighth invention is a weighing device according to any one of the first to seventh inventions, and includes a plurality of weighing units. The weighing device further includes a determination unit. The determination unit determines the direction in which the wind blows using the calculated value obtained for each weighing unit.

  According to the measuring device according to the eighth aspect of the invention, it is easy to identify the source of wind that affects the measured value by determining the direction in which the wind blows. By identifying the source of wind, it becomes easier to remove the effects of wind.

  A weighing device according to a ninth aspect is the weighing device according to any one of the first to eighth aspects, and includes a plurality of weighing units arranged in a ring shape. Moreover, the determination part of this measuring device has a 1st and 2nd identification part. The first identification unit uses the plurality of calculated values obtained for each weighing unit to determine whether the plurality of calculated values are different for each weighing unit when there is no change in the amount of articles in the same weighing unit. . The second identification unit compares the calculated value with each of the two adjacent weighing units for the weighing unit that is determined by the first identification unit to have a plurality of calculated values different from each other. Determine if is the effect of wind.

  According to the weighing device according to the ninth aspect of the present invention, it is possible to more appropriately determine the influence of the wind by determining whether the cause of the difference between the plurality of calculated values is the influence of the wind.

  According to the measuring device according to the present invention, the influence of the wind on the measurement value is determined in consideration of the influence of the external vibration, so that the influence of the wind on the measurement value can be appropriately determined. Moreover, by determining the presence / absence of wind influence using a plurality of calculated values, it is possible to accurately determine the presence / absence of wind influence even when the measured value changes slowly with a large period.

1. Outline of Combination Weighing Device An outline of the combination weighing device 2 according to the embodiment of the present invention will be described with reference to FIG. The combination weighing device 2 includes a dispersion table 21, a vibration conveying device 22, a pool hopper 23, and a plurality of weighing hoppers H (n) (n is a natural number of 1 to N. Hereinafter, this is expressed as “n = 1 to N”. "). In FIG. 1, the article is indicated by a symbol P, and the flow of the article P is indicated by a solid arrow.

  The distribution table 21 has an umbrella shape and is arranged with the tip of the umbrella facing up. The dispersion table 21 is supported by a vibrator near the center, and vibrates by driving the vibrator. Thereby, the articles P placed on the upper surface of the dispersion table 21 are radially dispersed.

  A plurality of vibration transfer devices 22 are arranged around the dispersion table 21. The article P dispersed by the dispersion table 21 is placed on the vibration conveyance device 22. Then, the article P on the vibration transfer device 22 moves toward the pool hopper 23 by the vibration of the vibration transfer device 22.

  There are a plurality of pool hoppers 23, one for each vibration transfer device 22. Article P is put into the pool hopper 23 little by little from the corresponding vibration transfer device 22. Then, the pool hopper 23 temporarily stores the article P and throws it into the weighing hopper H (n) (n = 1 to N).

  The plurality of weighing hoppers H (n) (n = 1 to N) are arranged in a ring shape, and correspond to each of the pool hoppers 23. Each of the plurality of weighing hoppers H (n) includes a hopper 24, a door, and a measurement unit 11. In FIG. 1, the door and the measurement unit 11 are not shown.

  Articles P are put into the hopper 24 from the corresponding pool hopper 23. The door is attached to the hopper so as to be openable and closable, and is closed when the article P is stored, and is opened when the article P is discharged.

  The measuring unit 11 measures the weight of the article P put into the hopper 24. Specifically, each of the measuring units 11 belonging to the weighing hopper H (n) (n = 1 to N) measures the weight of the article P as a weighing value W (n) (n = 1 to N). For example, a load cell can be adopted as the measurement unit 11.

  In view of the fact that the weighing hopper H (n) measures the weight of the article P using the measuring unit 11, the weighing hopper H (n) can be grasped as the weighing unit.

  The weighing values W (n) measured by the plurality of weighing hoppers H (n) (n = 1 to N) are selected and combined so that the total weight of the articles P becomes a predetermined value. Then, the articles P are discharged only from the weighing hopper H (n1) indicating the selected weighing value (the symbol n1 indicates the number of the selected weighing hopper), and these are collected. The combination can be determined by, for example, combination calculation.

  On the other hand, the weighing hopper H (n2) that is not selected in the combination calculation (the symbol n2 indicates the number of the weighing hopper that is not selected) is not discharged into the hopper 24 until the next combination calculation without discharging the article P. The product P stands by with the articles P stored therein.

  2 and 3 show the transition of the measurement value W (n) measured by the measurement unit 11 (hereinafter referred to as “measurement value W (n, t)”, where the symbol t represents time). This is specifically shown by a graph 102 and a graph 103. The measured values W (n, t) shown in the graphs 102 and 103 include the effects of external vibration and wind.

  2 and 3 show times t1 to t4 when the combination calculation is executed. Specifically, at time t1, combination calculation is executed based on the measured value W (n, t) (n = 1 to N, t = t1) measured by the measurement unit 11 at or just before time t1. The same applies to the times t2 to t4. In the combination calculation, as described later, a value obtained by removing the influence of external vibration and wind from the measured value W (n, t) is used.

  Then, the weighing hopper H (n1) indicating the weighing value W (n1, t) selected by the combination calculation opens the door and discharges the article P. As a result, the measured value W (n1, t) becomes zero.

  The graph 102 in FIG. 2 shows that the metric value W (n, t) is selected in the combination calculation at times t1, t3, and t4. That is, immediately after the combination calculation at times t1, t3, and t4, the article P is discharged and the measurement value W (n, t) is zero.

  On the other hand, the graph 103 in FIG. 3 indicates that the measurement value W (n, t) has never been selected in the combination calculation at the times t1 to t4.

2. Control of combination weighing device <Determination of the presence of wind influence>
FIG. 4 is a block diagram showing the combination weighing device 2 according to the embodiment of the present invention. The combination weighing device 2 further includes a vibration detection unit 26 and a control unit 27 in addition to the above-described devices such as the weighing hopper H (n) (n = 1 to N). In FIG. 4, the dispersion table 21, the vibration transfer device 22, and the pool hopper 23 are not shown.

  The vibration detection unit 26 detects the influence of the external vibration transmitted to the measurement unit 11 on the measurement value W (n, t) in parallel with the measurement of the measurement value W (n, t) by the measurement unit 11. Specifically, the vibration detection unit 26 detects a deviation ΔW of the measurement value W (n) that is generated when the vibration of the floor is transmitted to the measurement unit 11. For example, AFV (Anti Floor Vibration) is adopted as the vibration detection unit 26.

  FIG. 5 is a graph 105 showing the transition of the deviation ΔW detected by the vibration detection unit 26 (hereinafter referred to as “deviation ΔW (t)”). The graph 105 in FIG. 5 shows a case where the vibration detection unit 26 detects external vibration at times t21 to t28.

  The control unit 27 includes a storage unit 271 and a determination unit 272. The storage unit 271 stores the measured value W (n, t) measured by each of the weighing hoppers H (n) (n = 1 to N) and the deviation ΔW (t) detected by the vibration detecting unit 26. .

  6 and 7 show the measured value W (n, t) and the deviation ΔW (t) stored in the storage unit 271. FIG. In FIG. 6, the measured values W (n, t) (FIGS. 6A and 6B) and the deviation ΔW (t) (FIG. 6C) stored in the storage unit 271 at time t2 are obtained. Are shown by graphs 1061 to 1063, respectively. In FIG. 7, the measured value W (n, t) (FIGS. 7A and 7B) and the deviation ΔW (t) (FIG. 7C) stored in the storage unit 271 at time t4 are obtained. Are shown by graphs 1071 to 1073, respectively.

  Based on the measured value W (n, t) (n = 1 to N) and the deviation ΔW (t) stored in the storage unit 271, the determination unit 272 determines the wind to the measured value W (n, t). The presence or absence of the influence of. Specifically, it is as follows.

  First, a case where the determination unit 272 determines whether or not there is an influence of wind at the time t2 will be described. The determination unit 272 determines the weighing hopper H (s) that has never been selected from the weighing value W (n, t) (n = 1 to N) stored in the storage unit 271 over the continuous combination calculation. (Symbol s indicates the number of the weighing hopper not selected in the combination calculation). Since the weighing hopper H (s) has never been selected, there is no change in the amount of articles in the hopper 24 of the same weighing hopper H (s).

  Specifically, the determination unit 272 selects the measurement value W (n) not selected in the first (time t1) combination calculation from the measurement values W (n, t) illustrated in FIGS. 6 (a) and 6 (b). , T) (FIG. 6B) is selected as the measured value W (s, t).

  After selecting the measurement value W (s, t), the determination unit 272 removes the influence of the external vibration detected by the vibration detection unit 26 from the measurement value W (s, t). Specifically, the determination unit 272 subtracts the deviation ΔW (t) (FIG. 6C) stored in the storage unit 271 from the measured value W (s, t) (FIG. 6B). A measured value W1 (s, t) from which the influence of vibration is removed is obtained.

  FIG. 8 is a graph 108 showing the measured value W1 (s, t) from which the influence of external vibration has been removed. Comparing the graph 108 with the graph 1062 (FIG. 6B), it can be seen that the external vibration generated at the times t21 to t23 is removed.

  After obtaining the measured value W1 (s, t), the determination unit 272 uses the measured value W1 (s, tc0) at a certain time tc0 as a reference, and the measured value W1 (s) at the time tc1 after the lapse of the predetermined time Δtc. , Tc1) is obtained as ΔW1 (tc1).

  Specifically, as shown in FIG. 8, the change amount ΔW1 (tc1) is obtained by subtracting the reference measurement value W1 (s, tc0) from the measurement value W1 (s, tc1) at the time tc1. In FIG. 8, the time t1 when the combination calculation is first performed after the article P is put into the weighing hopper H (s) is used as the time tc0. As the predetermined time Δtc, a time interval Δt for executing the combination calculation is employed. Therefore, the time tc1 is equal to the time t2 when the second combination calculation is performed.

  The determination unit 272 determines whether or not the weighing of the combination weighing device 2 is affected by wind using the change amount ΔW1 (tc1). Specifically, the determination unit 272 determines that there is an influence of wind when the change amount ΔW1 (tc1) is larger than the predetermined value ΔW11. On the other hand, if the change amount ΔW1 (tc1) is smaller than the predetermined value ΔW11, it is determined that there is no influence of the wind.

  That is, the determination unit 272 compares the measured value W1 (s, tc0) and the measured value W1 (s, tc3) to determine whether they are different. judge. This content can be grasped as follows. That is, the measurement values W1 (s, tc0) and W1 (s, tc1) used when obtaining the change amount ΔW1 (tc1) are the measurement values W (s, t) detected by the measurement hopper H (s), It can be grasped as a plurality of calculated values obtained based on the influence of the external vibration detected by the vibration detection unit 26 on the measurement value W (s, t). And the determination part 272 will determine the presence or absence of the influence of the wind on the measured value W (n, t) using several calculated value (metric value W1 (s, tc0), W1 (s, tc1)). I can grasp it.

  In the combination weighing device 2 described above, the weighing values W1 (s, tc0) and W1 (s,) are obtained by using the weighing values W (s, t) obtained by the same weighing hopper H (s) in which the amount of the article does not vary. tc3). For this reason, when a difference occurs between the plurality of measurement values W1 (s, tc0) and W1 (s, tc3), the difference occurs even though there is no change in the amount of articles. Therefore, the determination unit 272 determines that the wind has an influence on the measurement value W (n, t) when the plurality of measurement values W1 (s, tc0) and W1 (s, tc3) are different. it can.

  FIG. 8 shows a case where the change amount ΔW1 (tc1) is smaller than a predetermined value ΔW11. That is, there is almost no difference between the plurality of measured values W1 (s, tc0) and W1 (s, tc3). In this case, the determination unit 272 determines that there is no wind influence.

  Similarly, every time a predetermined time Δtc elapses from time tc0 (time tc1, tc2,..., Tcm (m is a natural number)), the determination unit 272 determines the measured value W1 (s, tcm). The change amount ΔW1 (tcm) is obtained by subtracting the measured value W1 (s, tc0) from the value. And the determination part 272 determines the presence or absence of the influence of a wind by comparison with variation | change_quantity (DELTA) W1 (tcm) and predetermined value (DELTA) W11.

  Specifically, the case where the determination unit 272 determines whether or not there is an influence of wind at the time t4 will be described. The determination unit 272 selects the measurement value W (n, t) that is not selected in any of the combination calculations at the times t1 to t3 among the measurement values W (n, t) illustrated in FIGS. (FIG. 7B) is selected as the measured value W (s, t).

  Then, the determination unit 272 subtracts the deviation ΔW (t) (FIG. 7C) stored in the storage unit 271 from the measured value W (s, t) (FIG. 7B), and affects the influence of external vibration. The weighed value W1 (s, t) from which is removed is obtained.

  FIG. 9 is a graph 109 showing the measured value W1 (s, t) from which the influence of external vibration has been removed. Comparing the graph 109 with the graph 1072 (FIG. 7B), it can be seen that the external vibration generated at the times t21 to t27 is removed.

  After obtaining the measured value W1 (s, t), the determination unit 272 uses the measured value W1 (s, tc0) at time tc0 as a reference, and the measured value W1 (time tc3 after a predetermined time 3 · Δtc has elapsed). The amount of change ΔW1 (tc3) of s, tc3) is obtained. Specifically, as illustrated in FIG. 9, the determination unit 272 obtains the change amount ΔW1 (tc3) by subtracting the measurement value W1 (s, tc0) from the measurement value W1 (s, tc3). Note that the measured values W1 (s, tc0) and W1 (s, tc3) can be grasped as a plurality of calculated values in the same manner as described above.

  Then, the determination unit 272 compares the change amount ΔW1 (tc3) with the predetermined value ΔW11 to determine whether the measurement of the combination weighing device 2 is affected by wind. That is, the determination unit 272 compares the measured value W1 (s, tc0) and the measured value W1 (s, tc3) to determine whether they are different. judge.

  FIG. 9 shows a case where the change amount ΔW1 (tc3) is larger than a predetermined value ΔW11. That is, a large difference occurs between the plurality of measurement values W1 (s, tc0) and W1 (s, tc3). In this case, the determination unit 272 determines that there is an influence of wind.

  According to the control of the combination weighing device 2 described above, it is possible to appropriately determine whether or not there is an influence of wind on the measurement value W (n, t) in consideration of the influence of external vibration. And since the presence or absence of the influence of a wind is determined using several measured value W1 (s, tcm), the determination system is high.

  Furthermore, since the presence / absence of wind influence is determined using a plurality of measured values W1 (s, tcm) every predetermined time Δtc, the measured values W1 (n, t) are gradually increased with a period larger than the time interval Δt. ) Can be accurately determined whether or not there is an influence of wind. Therefore, the above-described technique is particularly suitable when the wind of the air conditioner that periodically changes the wind direction affects the measurement value W (n, t).

  Even when the measured value W1 (n, t) changes slowly with a large period, it is preferable to make the predetermined time Δtc larger than the time interval Δt from the viewpoint of enhancing the determination system for the presence or absence of the influence of wind. .

  For example, the predetermined time Δtc may be longer than the mechanical operation cycle of the combination weighing device 1. As a mechanical operation cycle of the combination weighing device 1, for example, a cycle of opening / closing the weighing hopper H (n) can be adopted.

  Further, when the external vibration detected by the vibration detection unit 26, that is, the variation of ΔW (t) is large and the variation is not within the predetermined range, it is not determined whether there is an influence of the wind, and the external vibration is appropriate. It is preferable to judge that accurate weighing is not possible.

<Reflection of wind effect on measurement value>
When the determination unit 272 determines that there is an influence of wind, the control unit 27 reflects the influence of the wind on the measurement value W1 (n, t). This will be specifically described below.

  The control unit 27 further includes a storage unit 273, a correction unit 274, and a calculation unit 275 in addition to the storage unit 271 and the determination unit 272 (FIG. 4).

  The storage unit 273 has a plurality of change amounts ΔW1 that are differences between each of the measured values W1 (s, tcm) at different times tcm (m is a natural number) and the reference measured value W1 (s, tc0). (Tcm) is stored.

  The calculation unit 275 creates a distribution of appearance frequencies of the change amount ΔW1 (tcm) using the plurality of change amounts ΔW1 (tcm) stored in the storage unit 273. And the calculating part 275 calculates | requires standard deviation (sigma) from this distribution.

  When the determination unit 272 determines that there is an influence of wind, the correction unit 274 uses the standard deviation σ obtained by the calculation unit 275 and uses the target value W0 for the combination calculation of the measurement value W (n, t). Correct. This will be specifically described below.

  First, the determination unit 272 notifies the correction unit 274 by the signal S that it has been determined that there is an influence of wind at time tc3.

  Upon receiving the signal S, the correction unit 274 receives the measurement value W (n, t) (n = n) from each of the measurement units 11 of the measurement hopper H (n) (n = 1 to N) at the time t when the combination calculation is executed. 1 to N) and the deviation ΔW (t) is acquired from the vibration detection unit 26. Then, the correction unit 274 subtracts the deviation ΔW (t) from each of the measurement values W (n, t) (n = 1 to N) to obtain the measurement value W1 (n, t) from which the influence of external vibration has been removed. Ask.

  In parallel with this, the correction unit 274 acquires the standard deviation σ from the calculation unit 275. The correction unit 274 is a value (3 · σ · √M) obtained by multiplying a value (3 · σ) three times the standard deviation σ by the square root (√M) of the combination number M of the measured values W (n, t). Ask for. Then, the correction unit 274 corrects the target value W0 of the combination calculation by adding or subtracting the value (3 · σ · √M) to the measured value W1 (n, t). In addition, the value of 3-4 is employ | adopted for the number M of combinations. Further, the value (3 · σ) three times the standard deviation σ may be a value (2 · σ) twice the standard deviation σ, for example.

  According to the control of the combination weighing device 2 described above, by correcting the target value W0 of the combination calculation by the correction unit 274, the influence of wind can be reflected in the target value W0 in the combination calculation. Therefore, the articles after combination can be weighed without falling below the target value before correction.

  In the control of the combination weighing device 2 described above, the influence of the wind is reflected by correcting the target value W0 of the combination calculation. For example, the influence of the wind may be reflected as follows. That is, when the determination unit 272 determines that there is an influence of wind, the correction unit 274 uses the standard deviation σ obtained by the calculation unit 275 to measure the measurement value W ( n, t) is corrected.

<Modification 1>
The combination weighing device 2 described above can determine the direction in which the wind blows which affects the measured value W (n, t) (n = 1 to N). FIG. 10 shows such a combination weighing device 2 in a block diagram.

  The combination weighing device 2 further includes a determination unit 276. The discriminating unit 276 discriminates the direction in which the wind blows using the measured value W1 (n, t) obtained for each weighing hopper H (n). Specifically, it is as follows.

  The storage unit 273 stores a change amount ΔW1 (tcm) (hereinafter referred to as “change amount ΔW1 (n, tcm)”) for each of the weighing hoppers H (n). The change amount ΔW1 (n, tcm) is obtained in the same manner as described in the above “determining whether there is an influence of wind”.

  The determination unit 276 acquires the change amount ΔW1 (n, tcm) stored in the storage unit 273 from the storage unit 273, and calculates the change amount ΔW1 (n, tcm) at a certain time tcm between the weighing hoppers H (n). Compare with.

  As a result of the comparison, the determination unit 276 selects the weighing hopper H (n3) having the largest change amount ΔW1 (n, tcm) (the sign n3 indicates the number of the selected weighing hopper). The discriminating unit 276 winds from the selected weighing hopper H (n3) side (the direction from the center toward the weighing hopper H (n3)) as viewed from the center of the annularly arranged weighing hopper H (n). It is judged that is blowing.

  According to the combination weighing device 2 according to the present modification, it is easy to identify the source of wind that affects the measured value W (n, t) by determining the direction in which the wind blows. By identifying the source of wind, it becomes easier to remove the effects of wind.

<Modification 2>
In the combination weighing device 2 described above, when the change amount ΔW1 (tcm) is larger than the predetermined value ΔW11, the determination unit 272 determines that there is an influence of wind (FIGS. 4 and 9). It is more preferable to perform the determination by the determination unit 272.

  FIG. 11 is a block diagram showing the combination weighing device 2 according to this modification. The determination unit 272 includes first and second identification units 2721 and 2722. Hereinafter, a case where the determination unit 272 performs determination at time tcm will be described.

  The first identification unit 2721 determines whether or not the change amount ΔW1 (n, tcm) is greater than the predetermined value ΔW11 for each of the weighing hoppers H (n). Such a determination is performed in the same manner as described above in the “determination of presence / absence of wind influence”.

  When the first identification unit 2721 determines that the change amount ΔW1 (n, tcm) is greater than the predetermined value ΔW11 for any of the weighing hoppers H (n), the second identification unit 2722 displays the change amount ΔW1. (N4, tcm) (reference number n4 indicates the number of the weighing hopper whose change amount ΔW1 (n, tcm) is greater than the predetermined value ΔW11) is greater than the predetermined value ΔW11 (hereinafter referred to as “variation cause”). ) Is due to the influence of wind.

  Specifically, the second identification unit 2722 includes a change amount ΔW (n4, tcm) for the weighing hopper H (n4) and two weighing hoppers H (n4-1) adjacent to both sides of the weighing hopper H (n4). ) And H (n4 + 1) are compared with variations ΔW1 (n4-1, tcm) and ΔW1 (n4 + 1, tcm).

  Then, based on the magnitude relationship between the change amounts ΔW (n4-1, tcm) to ΔW (n4 + 1, tcm), it is determined whether the cause of variation is due to the influence of the wind. This will be specifically described with reference to FIG.

  FIG. 12 shows the magnitude relationship (hereinafter simply referred to as “magnitude relationship”) of the change amounts ΔW (n4-1, tcm) to ΔW (n4 + 1, tcm) and the determination contents associated with the magnitude relationship. FIG. As shown in FIG. 12, when the magnitude relationship is “large, large, large”, it is determined that the cause of fluctuation is due to the influence of the wind.

  When the magnitude relationship is “small, large, large”, the same determination as described above is performed again for three weighing hoppers H (n4) to H (n4 + 2) with the weighing hopper H (n4 + 1) as the center. Execute.

  When the magnitude relationship is “Large, Large, Small”, the three adjacent hoppers H (n4-2) to H (n4) with the weighing hopper H (n4-1) as the center are the same as described above. The above determination is executed again.

  When the magnitude relationship is “small, large, small”, it is determined that the cause of fluctuation is due to another influence different from the wind.

  On the other hand, if the first identification unit 2721 determines that the change amount ΔW1 (n, tcm) is smaller than the predetermined value ΔW11 for any of the weighing hoppers H (n), the second identification unit 2722 Judge that there is no impact.

  According to the combination weighing device according to this modification, it is possible to determine whether or not the cause of the fluctuation is the influence of the wind, so that the influence of the wind can be more appropriately determined. In addition, only when the influence of the wind is determined, the influence of the wind may be reflected on the target value of the combination calculation or the measurement value W (n, t), and thus the correction can be appropriately performed.

It is the figure which showed notionally the combination weighing | measuring device concerning embodiment of this invention. It is the figure which showed the measurement value W (n, t) measured by the measurement part with the graph. It is the figure which showed the measurement value W (n, t) measured by the measurement part with the graph. It is the block diagram which showed the combination weighing | measuring device notionally. It is the figure which showed the external vibration detected by the vibration detection part with the graph. It is the figure which showed the measured value W (n, t) and deviation (DELTA) W (t) memorize | stored in the memory | storage part. It is the figure which showed the measured value W (n, t) and deviation (DELTA) W (t) memorize | stored in the memory | storage part. It is the figure which showed the measurement value W1 (s, t) which removed the influence of the external vibration with the graph. It is the figure which showed the measurement value W1 (s, t) which removed the influence of the external vibration with the graph. It is the block diagram which showed notionally the combination weighing device concerning the modification 1. It is the block diagram which showed notionally the combination weighing | measuring device concerning the modification 2. It is the figure which showed the magnitude relationship of three variation | change_quantity, and the determination content linked | related.

Explanation of symbols

2 Combination Weighing Device 26 Vibration Detection Unit 272 Judgment Unit 273 Storage Unit 274 Correction Unit 275 Calculation Unit 276 Discrimination Unit 2721 First Identification Unit 2722 Second Identification Unit H (n) Weighing Hopper (Weighing Unit)
W0 Target value for combination calculation W (n, t) Weighing value ΔW (t) Deviation (effect of external vibration)
W1 (n, t) Weighing value (calculated value)
ΔW1 (s, tcm) Amount of change (difference)
tc0 time (first time)
tcm time (second time)
Δtc Predetermined time σ Standard deviation

Claims (9)

A weighing unit for weighing the article;
A detection unit for detecting external vibration;
Using a plurality of calculation values obtained based on the measurement value measured by the measurement unit and the influence of the external vibration detected by the detection unit on the measurement value, the influence of wind on the measurement value A weighing device including a determination unit that determines presence or absence. The determination unit determines that there is an influence of the wind when the plurality of calculated values are different when there is no change in the amount of the article in the same measurement unit,
The weighing device according to claim 1. The one calculated value among the plurality of calculated values is obtained based on the measurement value and the influence of the external vibration at a first time,
The other calculated values of the plurality of calculated values are obtained based on the measurement value and the influence of the external vibration at a second time after a predetermined time has elapsed from the first time,
The determination unit determines the presence or absence of the influence of the wind by comparing the other calculated value and the one calculated value.
The weighing device according to claim 2. The predetermined time is different from a mechanical operation cycle of the weighing unit,
The weighing device according to claim 3. A storage unit that stores a difference between each of the other calculation values at a plurality of different second times and the one calculation value;
Using the difference stored in the storage unit, a calculation unit for obtaining a standard deviation from the distribution of the difference,
When the determination unit determines that there is an influence of the wind, using the standard deviation obtained by the calculation unit, a correction unit that corrects the measurement value obtained by the measurement unit;
The metering device according to claim 3 or 4, further comprising: The weighing device according to claim 3 or 4, wherein the weighing device includes a plurality of the weighing units, and performs combination calculation that combines the measured values measured by the weighing units.
A storage unit that stores a difference between each of the other calculation values at a plurality of different second times and the one calculation value;
Using the difference stored in the storage unit, a calculation unit for obtaining a standard deviation from the distribution of the difference,
A correction unit that corrects a target value of the combination calculation using the standard deviation obtained by the calculation unit when the determination unit determines that there is an influence of the wind;
A weighing device further comprising: In the case where there is no variation in the amount of the article in the same weighing unit, the determination unit has a plurality of variations in the external vibration detected by the detection unit at different times within a predetermined range, and the measured value and the measurement value When a plurality of the calculated values excluding the influence of the external vibration obtained based on the external vibration are different, it is determined that there is an influence of the wind.
The weighing device according to claim 1. A plurality of the measuring units are provided,
The discriminating unit discriminates the direction in which the wind blows using the calculated value obtained for each of the weighing units.
The weighing device according to any one of claims 1 to 7. The weighing device according to any one of claims 1 to 8, wherein the weighing unit is arranged in a plurality of annular shapes.
The determination unit includes first and second identification units,
The first identification unit uses the plurality of calculated values obtained for each of the weighing units, and the plurality of calculated values in the case where there is no change in the amount of the article in the same weighing unit for each of the weighing units. To determine if they are different,
The second identification unit compares the calculated value with each of the two adjacent weighing units for the weighing unit determined by the first identifying unit to be different from the plurality of calculated values, Determining whether the cause of the difference between the plurality of calculated values is the influence of the wind,
Weighing device.

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