JPH1137828A - Correcting apparatus for dynamic measured value - Google Patents

Abstract

PROBLEM TO BE SOLVED: To correct the vibrational component of a measured signal of a preceding article remaining in a measured signal of a following article. SOLUTION: One region W(TM) corresponding to the read timing of a following article, out of correcting storage regions W(1)-W(m) where the vibrational components of a sample article have been stored, is read (Step S52), and the ratio of the stationary weight of a preceding article to the stationary weight Ws of the sample article is multiplied (Step S54). This is subtracted from W(TM) (Step S56), and this subtracted value is converted into a weight value WN (Step S58).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a correction device for correcting an error component included in a dynamic weighing signal obtained from a weighing conveyor for weighing articles while conveying the articles.

[0002]

2. Description of the Related Art Since weighing means provided on a weighing conveyor, for example, a weight sensor, is a linear secondary vibration system,
When an article gets into and out of the weighing conveyor, a transient vibration wave is generated from the weight sensor. The weighing conveyor may be provided in the weight sorter. The weight sorter continuously weighs the articles fed to the weighing conveyor. After a certain period of time has elapsed after the preceding article has passed through the weighing conveyor, and when the vibration wave generated when the preceding article leaves the weighing conveyor has sufficiently converged, the subsequent article sets the weighing timing on the weighing conveyor. When it arrives, the succeeding article can be weighed without being affected by the preceding article.

However, if the interval between the preceding and following articles is short and the transient vibration wave of the preceding article has not yet sufficiently converged, when the timing of weighing the following article is reached,
Since the weight sensor is a linear system, the superposition theorem causes the weighing wave of the succeeding article to be superimposed with the vibration wave of the preceding article having a size that cannot be ignored in accuracy, and the weighing accuracy of the succeeding article decreases. If the distance between the preceding article and the succeeding article is always constant, even if it is short, the waveform of the preceding article is superimposed on the waveform of the succeeding article in the same state each time, so that the succeeding article is always considered to be constantly affected. be able to. However, considering the articles that first enter the weighing conveyor and the subsequent articles that enter the weighing conveyor at various intervals, the convergence state of the transient waveform of the preceding article differs at each time interval. receive. Therefore, even if the articles have the same weight, the weight value varies depending on the presence or absence of the preceding article and the difference in the distance from the preceding article.

As described above, when weighing continuously supplied articles at short non-uniform time intervals in the weighing conveyor, the weighing value of the following article is affected by the weighing value of the preceding article. Attention is paid to a technique for performing the correction, for example, as disclosed in JP-A-6-82294 and JP-A-2-206726. For these, the correction amount is determined in advance, the time between the preceding article and the succeeding article is measured, the correction amount is corrected according to the measured time, and the weighing value is corrected by the corrected correction amount.

[0005] All of these objects are intended to correct an error caused by a response delay of an analog filter provided in a weight measuring circuit. That is, during the weighing of the succeeding article, there is a phenomenon that a transient waveform component of the weighing signal of the preceding article remains in the analog filter, and this residual signal gives an error to the weighing signal of the succeeding article. This is because an analog filter having a large time constant is used to smooth the oscillating weighing signal.

[0006]

In recent measurement of weighing signals, digitization is progressing, and A /
Due to the high speed of the D converter and the low cost of the digital operation circuit, an analog filter having a large time constant is rarely used as a means for smoothing the vibration wave of the weighing signal, and a digital filter having a fast transient response is often used. Has become. Therefore, the weighing signal of the preceding article does not remain in the digital filter during the weighing of the succeeding article. However, during the weighing of the succeeding article, a vibration component of the weighing signal of the preceding article remains, and it is necessary to correct this vibration component in order to obtain an accurate weighing value. This vibration component oscillates positively and negatively around 0. Therefore, the conventional technique of correcting the above-described fixed correction amount according to the time interval between the preceding article and the succeeding article cannot be applied to the correction of the vibration component.

An object of the present invention is to correct a vibration component of a weighing signal of a preceding article remaining in a weighing signal during weighing of a subsequent article.

[0008]

According to the first aspect of the present invention,
It has a weighing conveyor provided with transport means for sequentially feeding articles, and weighing means for generating a weighing signal based on the transport of the articles by the transport means. In this weighing conveyor, the vibration component due to the weighing of the preceding article remains in the weighing signal generated when the preceding article separates from the transporting means and the subsequent article is being transported through the transporting means. ing. Further, the invention according to claim 1, wherein the correction storage means for storing the weighing signal of the preceding article at the timing of capturing the weighing signal of the subsequent article, and the weighing at the capturing timing of the subsequent article. Calculating means for subtracting the value stored in the correction storage means from the signal.

According to the first aspect of the present invention, the weighing signal corresponding to the vibration component due to the weighing of the preceding article is stored in the correction storage means. By subtracting the weighing signal corresponding to the vibration component, an error due to the vibration component due to the measurement of the preceding article can be removed.

According to a second aspect of the present invention, in the dynamic weighing value correcting apparatus according to the first aspect, the correction storage means comprises:
After a sample article having substantially the same weight as the preceding article is transported by the transport means, a weighing signal based on the sample article at a timing corresponding to the timing of taking in the weighing signal of the subsequent article is stored.

According to the second aspect of the invention, the correction value can be obtained by transporting the sample article by the transport means.

According to a third aspect of the present invention, in the dynamic weighing value correcting apparatus according to the second aspect, the correction storage means includes means for ending the transfer of the sample article by the transfer means;
At least the weighing signal from a state in which the weighing signal vibrates to a period in which it can be considered to have converged is stored.
Further, the invention according to claim 3 determines which timing of the period the take-in timing of the subsequent article corresponds to, and reads a storage value corresponding to the determined timing from the correction storage means. And correction value determining means for supplying the correction value to the calculating means.

According to the third aspect of the present invention, the transfer means completes the transfer of the sample article, and stores the weighing signal for a period from the state in which the weighing signal vibrates to the time when the weighing signal is considered to have converged. Means have memorized. And
It determines which of the periods stored in the correction storage means corresponds to the timing of taking in the following article, reads out the stored value corresponding to the determined timing, and corrects the data by this. Therefore, even if the distance between the preceding article and the succeeding article is not constant, the correction can be made accurately.

According to a fourth aspect of the present invention, in the dynamic weighing value correcting apparatus according to the third aspect, the correction storage means comprises:
It stores the weighing signal of the sample article after the sample article has passed through the predetermined position after the transport means until a period in which the weighing signal of the sample article can be considered to have converged, and the correction value determination means, Address generation means for generating a read address of the correction storage means from the time when the preceding article has passed the predetermined position of the transport means; and determining whether or not the subsequent article has reached the position for taking in the weighing signal thereof. Means, and when the determining means determines that the subsequent article has reached the take-in position,
Reading means for reading out the weighing signal of the sample article from the correction storage means according to the address generated by the address generation means.

According to the fourth aspect of the present invention, the address generating means starts generating an address when the preceding article reaches a predetermined position after the conveying means. The stored value corresponding to the vibration component of the preceding article at that time is corrected based on the address of the address generating means when the determining means determines that the succeeding article has reached the capturing position of the weighing signal. The data is read out from the storage means and supplied to the arithmetic means. Various positions can be considered as the predetermined position on the transporting means. For example, the position where the preceding article has entered the transport means, the position where the preceding article has reached when the weighing signal of the preceding article has stabilized, and the position where the preceding article has reached when the weighing signal of the preceding article has started to vibrate. Or a position where the preceding article has already descended from the transport means. Further, the determination as to whether or not the arriving position of the weighing signal of the succeeding article has been determined, for example, is to determine whether or not a predetermined time has elapsed from when the succeeding article has boarded the transporting means running at a constant speed, Detecting whether a succeeding article has reached a predetermined position on the conveying means (when the succeeding article arrives at this position, the weighing signal is stable), and detecting whether the preceding article has reached the sending position of the preceding article. A predetermined time (necessary for the succeeding article to reach a position where the weighing signal of the succeeding article is stable) after being detected in the vicinity (there may be a case where the article is still on the conveying means or a case where it has already descended from the conveying means). time)
And the like that detect that the time has elapsed.

According to a fifth aspect of the present invention, in the dynamic weighing value correcting apparatus according to any one of the first to fourth aspects, the weighing value of the preceding article and the weighing value of the sample article are stored. And a calculating means for multiplying the ratio of the measured value of the preceding article to the measured value of the sample article by the value read from the correction storage means and supplying the multiplied value to the calculating means.

According to the fifth aspect of the present invention, the ratio of the weight of the preceding article to the sample article is calculated, and this ratio is multiplied by the value read from the correction storage means. Even if the weight of the article is different, it can be handled.

According to a sixth aspect of the present invention, in the dynamic weighing value correcting apparatus according to any one of the first to fifth aspects, when the preceding article and the following article are simultaneously in the transporting means, When the timing of taking in the following article arrives, the means for stopping the taking in of the weighing signal from the weighing means, and when the vibration of the weighing signal by the preceding article can be considered to have converged, the taking-in timing of the following article becomes Means for outputting the weighing signal received from the weighing means as it is.

According to the sixth aspect of the present invention, when the distance between the preceding article and the succeeding article is short and both of them are in the transport means at the same time, none of the articles can be weighed. To stop. Also, when the distance between the preceding article and the following article is long and the vibration of the preceding article has sufficiently converged, when the succeeding article rides on the conveyance means, there is no need to correct it. Output.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION In an embodiment of the present invention, a weighing conveyor weighs an article, compares the weighed value with each reference value, and weighs the article to one of a plurality of ranks defined by each reference value. It is used for a weight sorter that sorts articles as applicable. As shown in FIG. 4, the weighing conveyor has conveying means, for example, a conveyor for supporting and conveying the articles on the upper surface, more specifically, a belt conveyor 2. Instead of a belt conveyor, a roller conveyor or the like can be used. The belt conveyor 2 is provided with weighing means, for example, a load cell 4.

Articles are continuously fed to the belt conveyor 2 from a feed conveyor 6 which is a similar belt conveyor. At the boundary between the feed conveyor 6 and the belt conveyor 2, a detecting means, for example, a photo sensor 8 is provided to detect the entry of an article into the belt conveyor 2. Also, from the belt conveyor 2,
Articles are fed to a feed conveyor 10, which is a similar belt conveyor.

As shown in FIG. 5, the output signal of the load cell 4 is amplified by the amplifier 12 and then converted by the A / D converter 14 into a digital signal. As the A / D converter 14, a high-speed A / D converter such as a successive approximation type or a delta-sigma type can be used. This A /
The D converter 14 converts the signal from the amplifier 12 into a digital signal at a predetermined sampling timing and supplies the digital signal to the CPU 18 via the input / output port 16. Also,
The A / D converter 14 has an internal clock generator, supplies an interrupt signal to the CPU 18 every time a sampling timing arrives, and responds to the interrupt signal.
The CPU is reading the digital conversion value. The predetermined sampling period is selected at a time interval sufficient for accurately reproducing the waveform of the transient response wave output from the load cell 4 from each digital conversion value. Each digital conversion value is smoothed by a digital filter implemented in the CPU 18.

The photo sensor 8 generates a detection signal every time an article is detected. This detection signal is also supplied to the CPU 18 via the input / output port 16.

The CPU 18 is provided with storage means, for example, a memory 20. This memory 20 stores a vibration waveform of the sample article as described later. The CPU 18 is further provided with a keyboard 22 and a display 24. The keyboard 22 is used, for example, to give a command to the CPU 18 when starting the storage of a vibration waveform of a sample article described later. In addition, the display 24 displays, for example, the weighing value of the weighing conveyor.

The principle of the present invention will be described with reference to FIG. The preceding article 26 gets on the belt conveyor 2,
A change in the waveform of the load cell 4 that occurs when the load cell 4 is conveyed and further separates from the belt conveyor 2 is indicated by a symbol a in FIG. In the waveform a, the vibration component a1 is generated even after the article descends from the belt conveyor 2. This vibration component a1 cannot be smoothed even by a digital filter realized by the CPU 18.

When the following article 28 rides on the belt conveyor 2 in a state where the vibration component 21 is converged, a waveform shown by a dotted line is generated. When 28 rides on the belt conveyor 2, a waveform b on which the vibration component 21 is superimposed is generated.

Therefore, the digital value c of the vibration component at the timing tn1 at which the digital conversion value of the following article is read from the A / D converter 14 into the CPU 18 is stored in the memory 20 in advance, and is read at the timing tn1. From digital conversion value d to digital value c
Is subtracted by the CPU 18 to obtain an accurate digital conversion value.

However, it is impossible to store the digital value c of the vibration component in the memory 20 in advance. However, since the articles weighed by the weight sorter have almost the same shape and their weights are relatively similar, the average weight of the articles weighed by the weight sorter is determined. As a sample article, there is almost no difference between the vibration component generated when weighing alone and the vibration component 21 generated even if any of the articles becomes the preceding article. Therefore, a value equivalent to the digital value c generated by the sample article is stored in the memory 20 and used.

However, the vibration component c can be used only when the preceding article and the following article always get on the belt conveyor 2 at the same interval. However, in reality, this interval is not always constant. Therefore, the following method is adopted.

The above-mentioned correction is possible when the preceding article and the following article are not on the belt conveyor 2 at the same time. The above correction is necessary when the vibration component generated in the output of the load cell 4 by the preceding article is not converged. The minimum time tL (time from when the preceding article is detected by the photo sensor 8 to when the following article rides) required to prevent the preceding article and the following article from simultaneously riding on the belt conveyor 2 is tL. Can be determined in consideration of the speed of the belt conveyor 2, which is substantially constant. Further, the time tH (time from when the preceding article is detected by the photo sensor 8) required for the weighing signal of the preceding article to be regarded as substantially converging can be determined in advance.

Then, only the sample article is conveyed on the belt conveyor 2, and as shown in FIG. 7, each digital conversion value of the weighing signal (vibration component) generated by the sample article during the period from tL to tH is stored in the memory 20. At each address. Then, after actually starting the weighing of the article, it is determined whether the reading timing of the following article falls in the period from tL to tH, and the stored value of the address corresponding to the determined timing is stored in the memory. 20 and is subtracted from the read digital conversion value.

Based on the above principle, the CPU 18
Will be described with reference to flowcharts shown in FIGS. First, a preparation operation using a sample article will be described. At the start of this preparatory work, if the static weight Ws of the sample article is known in advance, the static weight Ws
Is stored in the memory 20 by operating the keyboard 22. When the static weight of the sample article is unknown, the belt conveyor 2 is stopped, and when the static weight of the sample article is displayed on the display 24 on the belt conveyor 2, the keyboard 22 is operated and stored in the memory 20. Let it.

Next, the sample article is conveyed by a belt conveyor under the same conditions as when the articles are actually weighed a plurality of times, for example, M times.

Hereinafter, processing as shown in FIGS. 2A and 2B is executed by the CPU 18. FIG. 2A shows an interrupt process performed by the CPU 18 every time the A / D converter 14 generates an interrupt signal. First, it is determined whether the sample article is detected by the photo sensor 8 (Step S2). If no signal is detected, another process is performed. If it is detected, the count value of the counter T (which is realized by the CPU 18) set to 0 in the initial setting is incremented by 1 (step S4).
That is, the elapsed time from when the sample article is detected by the photo sensor 8 is measured. This count value is
It is determined whether tL is larger than tL stored in the memory 20 in advance (step S6). If the value of the counter T is smaller than tL, there is no need to store the waveform, so another process is performed.

If the value of the counter T is larger than tL, the A / D data (digital value of the vibration component) Wd from the A / D converter 14 at that time is read (step S8).
Then, each accumulation area ΣW (t
1) to ΣW (tm), corresponding to ΣW (T)
Is accumulated (step S10).

As is apparent from FIG. 7, when tL and tH are determined, the sampling period of the A / D converter 14 is known. It is known whether a value can be obtained. In this embodiment, a description will be given assuming that m sampling values are obtained. Each of these sampled values is the value t of the counter T.
1 (= tL) to tm (= tH). Therefore, in the memory 20 in advance, the accumulation areas {W (t1) to {W (t1)} corresponding to the respective sampling timings t1 to tm.
W (tm) is prepared, and among these, Wd is accumulated in the accumulation area ΣW (T) corresponding to the value of the counter T.
The values of these accumulation areas ΣW (t1) to ΣW (tm) are set to 0 in the initial setting.

Next, it is determined whether or not the value of the counter T is greater than tH (step S12). If the value is not greater, another process is performed. If the value is greater, the process is terminated. By performing such processing every time an interrupt signal is generated,
When the sample article is transported once by the belt conveyor, each digital conversion value from t1 to tm is ΔW
(T1) to ΣW (tm) are stored. By transporting the sample article M times, ΣW (t1) to ΣW
(Tm) stores the accumulated values of M digital conversion values from t1 to tm.

FIG. 2B shows a process executed by the CPU 18 by operating the keyboard 22, for example, after the sample article is conveyed by the belt conveyor M times. In this process, each accumulation area {W (t1) to {}
In order to specify W (tm), the value of a counter n constituted by the CPU 18 is set to 1 (step S1).
4), the value of the accumulation area ΣW (n) designated by the counter n is divided by M, and this is divided from m correction storage areas W (t1) to W (tm) provided in the memory 20 in advance. It is stored in W (n) specified by the counter n. The correction storage area is provided corresponding to the sampling timings t1 to tm.

Next, the value of the counter n is incremented by 1 (step S18), and it is determined whether the value of the counter n is larger than M (step S20). If it is smaller than M, the loop of steps S16, S18, S20 is executed until it becomes larger than M, and if it becomes larger than M, this processing ends.
Therefore, when the value of the counter n becomes larger than M, the sampling timings t1 to tm are stored in the correction storage area W (t1) to W (tm) when the sample article is conveyed by the belt conveyor 2 M times. The average value of the digital values obtained in is stored.

The reason for obtaining the average value is to improve the measurement accuracy. In order to obtain each digital value of the vibration component from tL to tH, the only processing that the operator needs to perform is to convey the sample article on the belt conveyor 2 M times. This work is also used in conjunction with the work conventionally performed to measure the dynamic weighing value over M times to convert the dynamic weighing value into the static weighing value and to obtain the average value. I can do it. Note that the conversion of the dynamic weighing value to the static weighing value is performed, for example, by calculating the ratio between the average value of the dynamic weighing value and the previously stored static weighing value Ws, and measuring the ratio by actually measuring the article. This is done by multiplying the dynamic metric value obtained at that time.

Next, at the time of actually weighing each article,
Among the processing executed by the CPU 18, the processing performed each time an interrupt signal is supplied from the A / D converter 14 will be described with reference to FIG.

First, it is determined whether or not the preceding article has been detected by the photo sensor 8 (step S22). If it has not been detected yet, this interrupt processing ends. If detected, the value of the counter T2 constituted by the CPU 18 (the value of the counter T2 is set to 0 in the initial setting) is incremented by 1 (step S).
24). Thereby, the time from when the preceding article is detected by the photo sensor 8 is measured.

Next, it is determined whether the succeeding article is detected by the photo sensor 8 (step S26). If not detected, this process ends. If detected, the value of the counter T1 constituted by the CPU 18 (the value of the counter T1 is set to 0 in the initial setting) is incremented by 1 (step S28). Thereby, the time from the detection of the succeeding article is measured. Note that this succeeding article becomes a preceding article for the third article following it. Therefore, in actuality, a counter for measuring the time from the detection of the preceding article for this third article is detected. T2 'is constituted by the CPU 18, which starts counting. However, since the description is complicated, a description of that point will be omitted.

Then, it is determined whether the value of the counter T1 is equal to the reading timing tn1 (see FIG. 7) (step S30). If it is not equal to the read timing tn1, this interrupt processing ends.

If the reading timing tn1 has been reached, it is determined whether the value of the counter T2 is greater than tL (step S32). If it is not greater than tL, it can be determined that the preceding article and the succeeding article are on the belt conveyor 2 at the same time, so that weighing is impossible, and the flag F provided in the memory 20 is set to 1 to indicate that. (Step S34), and the value of the counter T1 is set to 0 (Step S36) in order to determine the weighing timing of the next succeeding article.
This interrupt processing ends.

If it is determined in step S32 that the value of the counter T2 is larger than tL, it is determined whether the value of the counter T2 is smaller than tH (step S3).
8). If not less than tH, the vibration component of the preceding article is substantially converged and no correction is needed,
The flag F is set to 2 indicating that (step S40).
When it is determined that the value of the counter T2 is smaller than tH,
Since it is necessary to perform the correction, the flag F is set to 3 to indicate that (step S42). Subsequent to step S40 or S42, the value of the counter T1 is set to 0 in order to determine the weighing timing of the next succeeding article (step S4).
4) The A / D data W (tn1) at that time is read (step S46), and the value of the counter T2 at that time is
It is stored in the area TM in the memory 20 (step S4
8) This interrupt routine is terminated. The photo sensor 8 and the counter T1 function as means for determining that the succeeding article has reached the position where the weighing signal is captured. T
The value of M is used to read a stored value for correction from the memory 20 as described later. The photosensor 8 and the counter T2 function as an address generating means for reading out a stored value for correction from the memory 20.

As shown in FIG. 1, the CPU 18 sets the value of the flag F to 1, 2,
3 is determined (step S50).
If the value of the flag F is 1, since the preceding article and the succeeding article are on the belt conveyor 2 at the same time, measurement is impossible. Therefore, a message indicating that measurement is not possible is displayed on the display 24, and this process is terminated.

If the value of the flag is 3, correction is necessary, so that W (TM) corresponding to the value of the area TM is read from the correction storage areas W (t1) to W (tm) ( Step S52). Next, the static weight WR of the preceding article relative to the weight Ws of the sample article stored in the preparation stage
(This is already stored as described below.)
WR / Ws is obtained and multiplied by the read W (TM) (step S54). This takes into account the possibility that the variation between the weight of the sample article and the weight of the preceding article can usually be neglected, but there is such a variation that it cannot be ignored. That is, since the vibration component generated by the preceding article is generally proportional to the weight of the preceding article, WR / Ws is multiplied by W (TM).

Next, from the A / D converted data W (tn1) read in step S46, WR / Ws · W
(TM) is subtracted to remove the influence of the vibration component (step S56). Next, an appropriate constant is arithmetically operated on the data from which the vibration component has been removed, and the data from which the vibration component has been removed is converted into a static weight value WR (step S).
58). Then, the data W obtained for the next article
When processing (tn1), the weight value WN is stored as WR for use in step S54 (step S54).
60).

In step S50, when it is determined that the flag F is 3, the vibration of the weighing signal by the preceding article sufficiently converges, and then the succeeding article is transferred to the belt conveyor 2.
Therefore, steps S58 and S60 are executed without performing the correction process.

In the above embodiment, the fetch timing is set to tn1 from the time when the photo sensor 8 detects an article.
It was when time passed. However, when the article gets on the belt conveyor 2 and the time tn1 has elapsed, another photosensor is provided at a position where the article reaches, and a digital conversion value is taken from the A / D converter 14 by the output of this photosensor. May be. Thus, the counter T1 can be omitted. Alternatively, instead of the photo sensor 8, a photo sensor is provided at a position where the weighing signal of the article conveyed by the belt conveyor 2 is stable, for example, near the discharge end of the belt conveyor 2, and the photo sensor detects the article every time. At the same time, the digital weighing signal of the article may be fetched from the A / D converter 14 and, at the same time, time counting by the counter T2 may be started. In other words, this photosensor is also used as a means for starting the generation of an address for reading out the weighing signal for correction from the memory 20 and a means for starting to take in the weighing signal of the succeeding article. Also in this case, the counter T
1 can be omitted. In this case, it is desirable that the memory 20 store, among the digital values of the weighing signals of the sample articles, those which can be regarded as having converged after the capture timing. Alternatively, in place of the photo sensor 8, a position where the weighing signal of the succeeding article is not yet stable, for example, a position slightly centered from the discharge end of the belt conveyor 2,
A photo sensor for detecting an article is provided, and a counter T1 and a counter T2 are provided when the photo sensor detects the article.
May be started. Of course, in this case, tn
The value of 1 needs to be changed, and the weighing signal for correction stored in the memory 20 is also from when the photosensor detects the sample article to when the weighing signal of the sample article can be considered to have converged. is there.

[0052]

According to the first aspect of the present invention, since the vibration component of the weighing signal of the preceding article included in the weighing signal of the succeeding article can be removed, accurate weighing can be performed.

According to the second aspect of the invention, the value stored in the correction storage means in order to remove the vibration component of the weighing signal of the preceding article is conventionally corrected from the dynamic weighing value to the static weighing value. Therefore, it is not necessary for the operator to perform a new operation because the operation can be shared with the operation that has been performed.

According to the third and fourth aspects of the present invention, even if the interval between the preceding article and the succeeding article is not constant, the vibration component of the preceding article occurring at the timing of taking in the weighing signal of the succeeding article. Can be removed, so that measurement can be performed with high accuracy.

According to the fifth aspect of the present invention, even if the weight of the preceding article is not constant, it can be eliminated that this influences the correction.

According to the sixth aspect of the present invention, since the correction is performed only when the correction is possible and the correction is necessary, the vibration component due to the preceding article can be accurately removed.

[Brief description of the drawings]

FIG. 1 is a flowchart of a main routine at the time of actual operation of an embodiment of a dynamic weighing value correction device according to the present invention.

FIG. 2 is a flowchart of a preparation stage of correction of a dynamic weighing value according to the embodiment.

FIG. 3 is a flowchart of an interrupt routine at the time of actual operation according to the embodiment.

FIG. 4 is a diagram showing a schematic configuration of the embodiment.

FIG. 5 is a block diagram of the embodiment.

FIG. 6 is a diagram showing a change in an output waveform of the load cell according to the embodiment.

FIG. 7 is an enlarged view of an output waveform of a load cell according to the embodiment.

[Explanation of symbols]

2 Belt conveyor (conveying means) 4 Load cell (weighing means) 18 CPU (calculating means, correction value determining means, address generating means, determining means, reading means, stopping means, output means) 20 Memory (storage means for correction)

Claims (6)

[Claims] An article is sequentially provided with conveying means for feeding articles, and weighing means for generating a weighing signal based on the article being conveyed by the conveying means. When the weighing conveyer is conveyed through the conveyance means, the generated weighing signal has a vibration component due to the weighing of the preceding article remaining on the weighing conveyor. A correction storage unit that stores a weighing signal of the preceding article remaining in the signal, and a storage value of the correction storage unit from the weighing signal at a timing corresponding to the capture timing of the subsequent article. A dynamic weighing value correction device comprising: a subtraction operation means. 2. The dynamic weighing value correcting device according to claim 1, wherein the correcting storage means conveys the sample article having substantially the same weight as the preceding article by the conveying means, and then transmits the sample article. An apparatus for correcting a dynamic weighing value which stores a weighing signal based on the sample article at the timing of taking in the weighing signal of the article. 3. The dynamic weighing value correcting device according to claim 2, wherein said storage means determines that said transport means has finished transporting said sample article and said weighing signal has converged from a vibrating state. At least the weighing signal is stored until a period that can be considered, and further, it is determined which timing of taking in the subsequent article corresponds to which timing of the period, and the stored value corresponding to the determined timing is stored in the storage unit. An apparatus for correcting a dynamic weighing value, comprising: a correction value determination unit that reads from a correction storage unit and supplies the correction value determination unit to the calculation unit. 4. The dynamic weighing value correcting device according to claim 3, wherein the correction storage means converges the weighing signal of the sample article after the sample article has passed a predetermined position on the transport means. Weighing signal of the sample article up to a period in which it can be considered that the sampled article has been read, and the correction value determining means is configured to read the address of the correction storage means from when the preceding article has passed the predetermined position of the transport means. Address generation means for generating, and means for determining whether the subsequent article has reached the capture position of its weighing signal, and when the determination means determines that the subsequent article has reached the capture position, Reading means for reading out the weighing signal of the sample article from the correcting storage means according to the address generated by the address generating means. A correction device for quantity values. 5. The dynamic weighing value correcting apparatus according to claim 1, wherein the weighing value of the preceding article is stored, the weighing value of the sample article is stored, and the preceding article is stored. A calculating means for multiplying a ratio of the measured value to the measured value of the sample article by a value read from the correction storage means and supplying the multiplied value to the calculating means. 6. The dynamic weighing value correcting device according to claim 1, wherein said preceding article and said succeeding article are simultaneously taken in said transport means, and said succeeding article is taken in. Means for stopping the taking of the weighing signal from the weighing means when the timing comes; and when the fetching timing of the following article comes when the vibration of the weighing signal by the preceding article can be considered to have converged, the weighing Means for outputting the weighing signal taken from the means as it is.