JP2000258237A - Measuring device and fixed-cycle oscillatory wave removing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce response delay in an output signal to an input signal and to remove fixed-cycle oscillatory waves effectively from pre-correction weight signals. SOLUTION: A measuring device in an operating state removes fixed-cycle oscillatory waves N from pre-correction weight signals on which fixed-cycle oscillatory waves N are superimposed to create a corrected weight signal R. The measuring device is provided with a storage part in which two cycles of signals of fixed-cycle oscillatory waves N are stored, a phase difference changing means to sequentially change the phase differences between pre- correction weight signals W outputted from a load cell and fixed-cycle oscillatory wave signals N stored in the storage part, a synthetic weight signal computing means to add n-pieces of pre-correction weight signals W to fixed-cycle oscillatory wave signals N for every phase difference to compute synthetic weigh signals R0, R1,... Rn-1 for every phase difference, and a selecting means to select a synthetic weight signal R with the smallest standard deviation of the signals among the n-pieces of synthetic weight signals R.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a case where a periodic signal such as mechanical vibration or electric noise is superimposed on an output signal of a load detector such as a load cell.
The present invention relates to a weighing device capable of removing a periodic oscillation wave from the output signal and a periodic oscillation wave removing method.

[0002]

2. Description of the Related Art Conventionally, a weight signal before correction of a load detector (hereinafter referred to as a load cell) in which a periodic oscillation wave is superimposed as noise is processed by, for example, a notch filter to remove noise of the periodic oscillation wave. There is a way to do that. But,
The notch filter requires the data of the weight signal on which one or more periodic vibration waves are superimposed. Therefore, when the time during which the weight signal can be acquired for weighing the article is less than one period of the periodic vibration wave. Cannot effectively remove the periodic oscillation wave from the weight signal before correction by the notch filter, and the corrected weight signal may include an unacceptable error. Therefore, in the notch filter, it is necessary to set the acquisition time of the weight signal to be equal to or more than one cycle of the periodic oscillation wave to be removed, which causes a problem that the response of the output signal to the input signal is delayed by one cycle or more. . Of course,
In the case of removing a plurality of periodic oscillation waves superimposed on the weight signal, a delay occurs by a time corresponding to the number. Therefore, for example, when a notch filter is used in a weight sorter, this filter hinders an increase in the weight sorting speed of articles.

Accordingly, the applicant of the present application has proposed that even if the time during which the weight signal can be obtained is less than one period of the periodic oscillation wave, the response of the output signal to the input signal will not be delayed, Japanese Patent Application No. 55-156602 (Japanese Patent Application No. 1-3083) discloses a method for effectively removing a periodic vibration wave from a weight signal before correction on which a vibration wave is superimposed.
No.). In a weighing device to which the periodic vibration wave removing method is applied, a weighing conveyor 1 is supported by a load cell 2 as shown in FIG. 4, for example. The weighing conveyor 1 includes a driving pulley 3 and a driven pulley 4, and a conveyor belt 5 is hung on the driving pulley 3 and the driven pulley 4. The drive shaft of the first motor 6 is connected to the drive pulley 3, and when the first motor 6 rotates,
The driving pulley 3 and the driven pulley 4 rotate in synchronization with the first motor 6. The ratio of the rotation cycle of the first motor 6 to the driving pulley 3 and the driven pulley 4 is 1: N or 1: 1 /
N. Here, N is an integer. The eccentric center of gravity of each rotating body of the driving pulley 3, the driven pulley 4, and the first motor 6 generates a periodic vibration wave N (FIG. 1A) synchronized with the rotation cycle of the driving pulley 3 and the like. The periodic oscillation wave N is superimposed on the weight signal W (FIG. 1B) output from the load cell 2 as noise. In addition, the weighing device is provided with a rotation cycle detection sensor (not shown) made up of, for example, a photo sensor for obtaining a synchronization signal synchronized with the periodic oscillation wave. The rotation cycle detection sensor generates a synchronization signal every time one of the drive pulley 3, the driven pulley 4, and the first motor 6 having the longest rotation cycle makes one rotation.

[0004] According to the periodic oscillation wave removing method, first, the weighing device is set to the adjustment mode. Then, in a state where no load is applied to the weighing conveyor 1, only the fixed-period vibration wave signal N not including the weight signal is A / D converted (analog-digital conversion), and the digital fixed-period vibration wave signal N is converted into a synchronization signal. Is read and stored in the storage unit. The digital periodic oscillation wave signal N is data sampled at sufficiently short time intervals so that the periodic oscillation wave can be accurately reproduced. In other words, the data of the fixed-period vibration wave signal read immediately after the synchronization signal is arranged at the head address of the storage unit, and the subsequent data is arranged in chronological order. The time relationship is clarified.

Next, the main operation mode is set during the main operation. While the article 7 is being conveyed by the weighing conveyor 1, the CPU reads the synchronization signal generated by the rotation cycle detection sensor together with the uncorrected weight signal W on which the periodic oscillation signal N is superimposed. here,
During the actual operation, the CPU reads the synchronization signal within the time when the weight signal W can be acquired, so that the data of the periodic oscillation wave signal N superimposed on the weight signal W before correction is stored in the storage unit. The CPU can recognize which of the data of the certain periodic oscillation wave signal N is present. Next, the CPU compares the pre-correction weight signal W with the periodic oscillation wave signal N based on the synchronization signal, and subtracts the latter from the former to remove the periodic oscillation wave signal N, and thus the corrected weight signal is removed. Can be generated.

[0006]

However, the above-described method of removing the periodic oscillation wave requires a rotation cycle detection sensor and an input device for inputting a synchronization signal to the CPU, and thus has a problem that the cost is increased accordingly. In some cases, it is difficult to mount the rotation period detection sensor, and there is a problem that the mounting space is required. Also, for example, when the rotation speed of the first motor 6 is changed during the actual operation,
The period, amplitude, or waveform of the fixed-period vibration wave signal stored in the adjustment mode is different from that stored in the actual operation mode. There is a problem in that the changed periodic vibration wave signal N ′ cannot be removed from the uncorrected weight signal W obtained during operation.

According to the present invention, it is possible to reduce a response delay of an output signal with respect to an input signal without providing a rotation cycle detection sensor, to remove a periodic vibration wave from a weight signal before correction, Even if the period and amplitude of the vibration wave change during the actual operation, the fixed-period vibration wave signal stored in advance can be corrected to remove the changed fixed-period vibration wave from the weight signal before correction. And a method of removing a periodic oscillation wave.

[0008]

According to a first aspect of the present invention, there is provided a weighing device which removes the above-described periodic vibration wave from a pre-correction weight signal on which a periodic vibration wave is superimposed in an operating state to obtain a corrected weight signal. A storage unit in which a signal for at least one period of the periodic oscillation wave is stored,
Phase difference changing means for sequentially changing the phase difference between both the uncorrected weight signal output from the load detecting means and the periodic oscillation wave signal stored in the storage means; and the uncorrected weight for each of a plurality of phase differences A combined weight signal calculating means for adding the signal and the fixed-period vibration wave signal or subtracting the other from one to calculate a combined weight signal for each phase difference; and a signal variation or maximum among the plurality of combined weight signals. Selecting means for selecting a composite weight signal having a relatively small difference between the value and the minimum value;
It is characterized by having.

In a weighing device according to a second invention, in the first invention, the phase difference changing means stores the weight signal before correction in the predetermined weight value calculation signal acquisition section in the storage means. The present invention is characterized in that the phase of a fixed-period vibration wave signal is relatively shifted by a predetermined time shorter than one period time of the fixed-period vibration wave signal, and the phase difference between the two is sequentially changed. The weighing device according to a third aspect of the present invention is the weighing device according to the first or second aspect, wherein the constant stored in the storage means is based on speed information of a fixed-period vibration wave source that determines the period and amplitude of the fixed-period vibration wave. A correction means for correcting the periodic vibration wave signal is provided.

A weighing device according to a fourth aspect of the present invention is the weighing device according to the first or second aspect, wherein a signal for at least one cycle of the periodic oscillation wave is stored in the storage means at the time of zero adjustment of the weight signal. It is a feature. In the weighing device according to a fifth aspect, in the first or second aspect, the fixed-period vibration wave superimposed on the weight signal before correction is removed by the fixed-period vibration wave removal filter, and the corrected weight obtained by the removal is obtained. A switching means for switching between a switching position at which zero adjustment is performed by the zero adjustment means using a signal and a switching position at which a fixed-period vibration wave superimposed on the zero-adjusted weight signal before correction is stored in the storage means is provided. It is characterized by having.

According to a sixth aspect of the present invention, in the load detector, wherein the first and second two periodic oscillation waves are superimposed on the weight signal before the correction, the first periodic oscillation wave is removed. Generating a wave and storing a signal of at least one cycle of the first periodic oscillation wave, and generating a second periodic oscillation wave and storing a signal of at least one cycle of the second periodic oscillation wave And sequentially changing the phase difference between the uncorrected weight signal on which the first and second fixed-period vibration waves are superimposed and the stored first fixed-period vibration wave signal. The weight signal before correction and the first periodic oscillation wave signal are added to each other, or the other is subtracted from one, and the first signal is added to each of the phase differences.
Calculating a combined weight signal of the plurality of first combined weight signals; and selecting a second combined weight signal having a relatively small difference between the signal or the maximum value and the minimum value among the plurality of first combined weight signals; The phase difference between the combined weight signal and the stored second fixed-cycle vibration wave signal is sequentially changed, and the second combined weight signal and the second fixed-cycle vibration wave signal for each of the plurality of phase differences are added. Or calculating the third combined weight signal for each phase difference by subtracting the other from one, and the signal variation or the difference between the maximum value and the minimum value among the plurality of third combined weight signals is relatively small. Selecting a fourth combined weight signal.

A weighing device according to a seventh aspect of the present invention is a weighing device that generates a corrected weight signal by removing the fixed-period vibration wave from a weight signal before correction on which a fixed-period vibration wave is superimposed in an operating state. Storage means for storing a signal of at least one cycle of the periodic vibration wave; and a position of both of them based on the weight signal before correction output from the load detecting means and the periodic vibration wave signal stored in the storage means. Phase difference changing means for changing the phase difference to 0 or 180 degrees or an angle close thereto, and a state in which the phase difference between the uncorrected weight signal and the periodic vibration wave signal is set to 0 or 180 degrees or an angle close thereto And a combined weight signal calculating means for calculating a combined weight signal of the two and generating a corrected weight signal from which the periodic vibration wave has been removed.

An weighing device according to an eighth aspect of the present invention is a weighing device that generates a corrected weight signal by removing the fixed-period vibration wave from the uncorrected weight signal on which the fixed-period vibration wave is superimposed in an operating state. Storage means for storing a signal of at least one cycle of the periodic vibration wave; and a position of both of them based on the weight signal before correction output from the load detecting means and the periodic vibration wave signal stored in the storage means. A phase difference detecting means for detecting a phase difference, and calculating a combined weight signal of the uncorrected weight signal and the fixed-period vibration wave signal in a state where the phase difference between the two is 0 degree or 180 degrees or an angle close thereto. Combined weight signal calculating means for generating a corrected weight signal from which the periodic vibration wave has been removed. In a weighing device according to a ninth aspect, in the eighth aspect, the acquisition start time of the weight signal before correction used by the phase detection means for detecting a phase difference is determined by the composite weight signal calculating means. The method is characterized in that it is before the acquisition start time of the uncorrected weight signal used for calculating the weight signal.

According to the first to fifth aspects of the present invention, the phase difference between the weight signal before correction and the periodic oscillation wave signal stored in advance in the storage section is sequentially changed, and the composite weight signal for each of the plurality of phase differences is changed. Among them, it is possible to select a composite weight signal having a relatively small signal variation or a difference between the maximum value and the minimum value. In the selected synthesized weight signal, the phase difference between the periodic wave signal superimposed on the uncorrected weight signal and the periodic wave signal previously stored in the storage unit becomes 180 degrees or 0 degree. , That is, when both signal values are equal in magnitude and opposite in sign, or when both overlap, the selected composite weight signal has a periodic oscillation. The wave signal is completely or scarcely left, and a corrected weight signal from which noise that is a periodic oscillation wave signal is removed can be generated.

According to the second aspect of the present invention, the weight signal before correction can be applied to a weighing device that acquires the weight signal in a predetermined signal value calculation section for weight value calculation. Can be relatively shifted by a predetermined time shorter than one cycle time of the periodic oscillation wave signal to change the phase difference between the two. According to the third aspect, when the speed of the fixed-period vibration wave generation source changes and the period and the amplitude of the fixed-period vibration wave superimposed on the weight signal before correction change accordingly, it is stored in the storage means. It is possible to correct a certain periodic oscillation wave signal to a signal corresponding to the periodic oscillation wave after the change in speed. According to the fourth aspect, at the time of zero point adjustment, a signal for at least one cycle of the periodic oscillation wave can be stored in the storage unit.

According to the fifth aspect of the invention, when performing the zero adjustment, the fixed-period vibration wave elimination filter performs the correction to remove the fixed-period vibration wave superimposed on the weight signal before correction, and the zero-point adjusting means uses the corrected weight. Zero adjustment can be performed using the signal. When the periodic oscillation wave is stored in the storage unit, the switching position can be switched to store the periodic oscillation wave to be superimposed on the zero-adjusted weight signal before correction.

The sixth invention is a method for removing the first and second periodic oscillation waves from the weight signal before correction on which the first and second periodic oscillation waves are superimposed. The periodic vibration wave can be removed from the weight signal before correction in the same manner as in the first invention, and the weight signal from which the first periodic vibration wave has been removed is the second combined weight signal. Then, the second periodic oscillation wave can be removed from the second composite weight signal in the same manner as in the first invention, and thus the first and second periodic oscillation waves are removed. The weight signal obtained is the fourth combined weight signal.

According to the seventh aspect, the phase difference between the two is set to 0 degree or 180 degrees or an angle close thereto based on the weight signal before correction and the periodic vibration wave signal stored in the storage unit in advance. The combined weight signal of the two in the state can be calculated. This combined weight signal is a corrected weight signal from which noise, which is a periodic vibration wave signal, has been removed.

According to the eighth and ninth aspects, the phase difference between the two is detected based on the weight signal before correction and the periodic oscillation wave signal stored in the storage unit in advance, and based on the detected phase difference. The phase difference between the weight signal before correction and the periodic vibration wave signal is 0 degree or 180 degrees, or an angle close thereto,
In this state, the combined weight signal of both can be calculated. This combined weight signal is a corrected weight signal from which noise, which is a periodic vibration wave signal, has been removed.

According to the ninth aspect, when the weight signal before correction in the region where the degree of attenuation is relatively large in the transient state is used as the data for weight calculation, the weight error becomes large, so that it is difficult to use it as the data for weight calculation. In consideration of the fact that it can be used to calculate the phase difference, the acquisition start time of the uncorrected weight signal used to calculate the phase difference is determined by the acquisition of the uncorrected weight signal used to calculate the composite weight signal. By obtaining a large amount of data of the uncorrected weight signal before the start time, it is possible to detect the phase difference between both the uncorrected weight signal and the periodic vibration wave signal using these data. it can.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of a weighing device to which a periodic oscillation wave removing method according to the present invention is applied will be described with reference to the drawings. This weighing device is applied to a weight sorter. The weighing device includes a weighing conveyor 1 supported by a load cell 2, as shown in FIG. A feed conveyor 8 is provided at a stage preceding the weighing conveyor 1. In this weighing device, one cycle T of a predetermined periodic oscillation wave N (FIG. 1A) based on the eccentric gravity of each of the driving pulley 3, the driven pulley 4, and the first motor 6 is determined by the weight of the weighing device. The period of the natural vibration wave of the weighing conveyor 1 superimposed on the signal is longer than the period, and the length of the weight signal acquisition time (P to Q in FIG. 1B) set for the weighing of the article 7 is as described above. It is shorter than one cycle T of the predetermined periodic oscillation wave N. Therefore, in order to remove the predetermined periodic vibration wave N from the weight signal W by a conventional digital notch filter, for example, the data of the rising portion of the weight signal must be added to the weight calculation, thereby lowering the weighing accuracy. Will be done. Then, the delay of the response of the corrected weight signal to the pre-correction weight signal W increases. Therefore, the present invention provides a device in which such operating conditions are required, the cost is lower than in the past, the delay of the response of the corrected weight signal can be made extremely short, and the periodic oscillation wave N The present invention proposes a weighing device capable of effectively removing the water.

FIG. 5 is a block diagram of a weighing operation circuit of the weight sorter. The analog weight signal output from the load cell 2 is amplified by an amplifier 9 and converted into a digital weight signal W by an A / D converter (analog / digital converter) 10, and then an I / O circuit (input / output circuit). Input to CPU (microprocessor) 12 through 11. The setting display unit 13 is connected to the I / O circuit 11 and, for example, a sampling value (noise data) of the periodic oscillation wave signal N and a sampling value (weight) of the weight signal W before correction stored in the storage unit 14. Data), a sampling value of a combined weight signal R obtained by combining a sampling value of the periodic vibration wave signal N and a sampling value of the weight signal W before correction, and the like. In addition, various data such as acquisition times P to Q of the pre-correction weight signal W, commands, and the like can be input.

The storage unit 14 stores a program for operating the weight sorter (weighing device).
Furthermore, the sampling value of the periodic vibration wave signal N, the sampling value of the weight signal W before correction, and the sampling value of the composite weight signal R can be stored. Then, it is possible to store the calculation results, various data, and the like obtained by calculating various data with the progress of the program. The CPU 12 includes a phase difference changing unit, a composite weight signal calculating unit, a selecting unit, a periodic oscillation wave removing filter,
It has zero point adjusting means and switching means. Each of these means and each process of the periodic oscillation wave removal filter is executed by the CPU 12 according to a program stored in the storage unit 14.
Do.

The phase difference changing means is shown in FIGS.
As shown in (f), the fixed-period vibration wave signal N stored in the storage unit 14 with respect to the pre-correction weight signal W of a predetermined weight signal acquisition time (weight value calculation signal acquisition section) P to Q is obtained. phase is a means for sequentially changing the phase difference between them by a short predetermined time t ₁ by relatively shifting than one cycle time of the periodic vibration signal N the. The synthetic weight signal calculating means is shown in FIG.
As shown in FIGS. 1 (c) to 1 (f), the weight signal W before correction and the periodic wave signal N for each of the plurality of phase differences are added, and the combined weight signal R (R ₀ to R ₀₎ is added for each phase difference. R _n-1 ). Selection means, variations in the plurality of combined weight signal R ₀ ~R _n-1 of the signal is a means for selecting the smallest synthetic weight signal R _M.

The fixed-period vibration wave removal filter removes a natural vibration wave (not shown) of the weighing conveyor 1 superimposed on the weight signal W before correction to generate a corrected weight signal W _F1 (first notch filter). Constant-cycle vibration wave removal filter)
When provided with a digital notch filter to generate a corrected weight signal W _F2 by removing the periodic vibration N based on the driving pulley 3 and the like (second periodic vibration wave cancel filter), the. The first and second periodic oscillation wave removal filters are filters that generate a corrected weight signal W _F12 by removing the natural oscillation wave and the periodic oscillation wave N superimposed on the weight signal W before correction. The zero point adjusting means includes a corrected weight signal W _F12 generated by the first and second periodic oscillation wave removing filters.
Is used to adjust the zero point of the weight signal. The switching means removes the natural vibration wave of the weighing conveyor 1 and the periodic vibration wave N, which are superimposed on the weight signal W before correction by the first and second periodic vibration wave removing filters, and the corrected wave obtained therefrom is removed. A switching position at which zero adjustment is performed using the weight signal _WF12 by the zero adjustment means, and a first fixed-period vibration wave removal filter performs an operation of removing the natural vibration wave, and the zero-adjusted corrected weight signal W _This is a means for switching to a switching position at which the periodic vibration wave N superimposed on _F1 can be stored in the storage unit 14.

Next, the procedure for storing the data of the periodic oscillation wave signal N in the storage unit 14 in the adjustment stage before the actual operation of the measuring device configured as described above, and the operation of the periodic oscillation wave N during the actual operation. The procedure of the calculation for generating the corrected weight signal R _{MH from} which is removed will be described with reference to the flowcharts and the like shown in FIGS. First, the processing content of the adjustment stage will be described with reference to the flowchart shown in FIG. Article 7
In the state where is not on the weighing conveyor 1, the operator drives the weighing conveyor 1 and operates the zero adjustment key of the setting display unit 13 (S100). Then, CPU1
2 switches the switching position of the switching means to the zero point adjustment position. As a result, the first and second periodic oscillation wave removing filters remove the natural oscillation wave of the weighing conveyor 1 and the periodic oscillation wave N which are superimposed on the weight signal W before correction, and the zero point adjusting means. Performs zero adjustment using the corrected zero weight signal _WF12 obtained by this processing, and stores the zero weight value in the storage unit 14 (S10).
2). At the time of zero adjustment, a relatively long weight signal acquisition time can be tolerated, so that the natural vibration wave superimposed on the uncorrected weight signal W and the periodic vibration wave N are removed by the first and second periodic vibration wave removal filters. Is performed.

Then, the CPU 12 switches the switching position of the switching means to a position where the second fixed-period vibration wave removing filter is disconnected and the first fixed-period vibration wave removing filter performs an operation for removing the natural vibration wave ( S104) The storage unit 1 stores m-cycle noise data (see FIG. 6) of the periodic oscillation wave N superimposed on the zero-adjusted zero-point weight signal W after the zero adjustment.
4 (S106). Note that one cycle T of the periodic oscillation wave N uses the longest rotation cycle of the metering motor, the driving pulley 3 and the driven pulley 4. Here, the rotation cycle of the driving and driven pulley 4 is set to
Is one cycle T. And since one cycle is T, 1
The number of A / D sampling noise data of the periodic oscillation wave signal N for the period is n (= T / t). t is a sampling time interval.

Here, as shown in FIG. 6, an A / D converter
1 period of the periodic oscillation wave N sampled by 10
Each time of n noise data of the eye is t₀₁, T₁₁, ...
・, T _n-1.1, The noise data at each time is W₀₁, W₁₁,
・ ・ 、 W_n-1.1Each time of n noise data in the second cycle
The time is t₀₂, T₁₂, ..., t_n-1.2, The noise
Data is W₀₂, W₁₂, ..., W_n-1.2, ..., m laps
Each time of the n noise data of the period is t_0m, T_1m, ...
・, T_n-1.m, The noise data at each time is W_0m, W _1m,
・ ・ 、 W_n-1.mAnd Next, the periodic oscillation wave for m periods
Of noise data at the same timing in each cycle of the signal N
The average value is calculated, and the average periodic vibration wave signal N is calculated (S
108). In other words, the same first tie of m periods
Mining (same phase) t₀₁, T₀₂, ..., t_0mAt the time
Noise data W₀₁, W₀₂, ..., W_0mThe average of
W_Z0,..., N-th timing (same phase) t
_n-1.1, T_n-1.2, ..., t_{n- 1.m}At the time of
Is Data W_n-1.1, W_n-1.2, ..., W_n-1.mFlat
Average value W_Zn-1And Thereby, each of the n times t₀,
t₁, ..., t_n-1The average noise data at
_Z0, W_Z1, ..., W_Zn-1Becomes And this average
Two cycles of the noise data sequence are stored in the storage unit 14 in order of time.
It is stored (S110). This ends the adjustment phase.

Next, the contents of the processing in the main operation stage will be described with reference to the flowchart shown in FIG. In this actual operation state, the CPU 12 sets the switching position of the switching means to the first position.
Performs the operation of removing the natural vibration wave, but disconnects the second periodic vibration wave removal filter and switches to a position where the operation of removing the periodic vibration wave N is not performed. . Therefore, the pre-correction weight signal W shown in FIG. 1B does not have a relatively long delay in the transient response due to the second periodic oscillation wave removal filter, but contains the periodic oscillation wave N. First, when the article 7 is conveyed by the infeed conveyor 8 and detected by the article detection sensor (photo sensor) 15 provided in front of the weighing conveyor 1 (S200), the CPU 12 acquires the weight data of the article 7. Then, the timing P to be stored and the acquisition section (acquisition time) P to Q are automatically designated in accordance with preset conditions (S202). Weight data acquisition sections P to Q
This is the optimal timing for obtaining the weight value and is designated as a section. Then, CPU 12 reads in Fig 1 (b) weight data string correction weight before signal W to the periodic vibration wave N within a specified interval P~Q is superposed as shown in the A / D sampling time interval t _1, the time series It is stored in the storage unit 14 (S2
04).

The weight data string of the weight signal W before correction is W
_0, W _1, ···, and W _k. CPU12, the noise component of the two periods of the weight data sequence W _0, W _1, · · ·, shown in Figure 1, which is previously stored in the storage unit 14 with respect to W _k (a) periodic vibration N data (hereinafter, simply referred to as "noise data".) column _{W Z0, W Z1, ···,} W Zn-1,
W _Z0 , W _Z1 ,..., W _Zn-1 are called, and an operation of adding data at the same timing (phase) is performed. That is, W _d00 = W ₀ + W _Z0 , W _d10 = W ₁ + W _{Z1 ,.
dk0} = W _k + W _Zk to operation. This calculation is performed by the composite weight signal calculating means, and W _{d00 to} W _dk0 are the composite weight signals. The result of this operation is R ₀ in FIG. Next, the phase difference changing means generates the noise data strings W _Z0 , W _Z1 ,... Shown in FIG.
Is shifted to the left side of the figure by the sampling time interval t ₁ , that is, by one data, and the combined weight signal calculating means adds the data of the weight data string and the noise data string at the same timing as described above. . W _d01 = W ₀ + W _Z1 , W _d11 = W ₁ + W _{Z2 ,.
dk1 = W k + W Z.k +} 1 and is calculated. The calculation result is R ₁ in FIG. 1 (d).

Further, the noise data sequence shown in FIG. 1D is further shifted to the left side of the figure by the sampling time interval t ₁ , and the weight data sequence and the noise data sequence at the same timing are compared with each other in the same manner as described above. to add. W _d02 = W ₀ + W _Z2 , W _d12 = W ₁ + W _Z3 ,..., W
_{dk2 = W k + W Z.k +} 2 and is calculated. The result of this operation is R ₂ in FIG. The synthetic weight signal data R ₂ has become a constant value, the noise data sequence from the weight data string correction weight before signal W periodic vibration waves N is one that was completely removed. Similarly shifted sequentially noise data string by t ₁ by combining the weight signal data string up to one period of the periodic vibration _{N R 3, R 4, ···} , obtaining the R _n-1. W _d0.n-1 = W ₀ + W _Zn-1 , W _d1.n-1 = W ₁ + W _{Z0 ,.
..} , W _dk.n-1 = W _k + W _Zk-1 . The result of this operation is R _n-1 in FIG. By sequentially shifting the noise data sequence for one cycle in this manner, n synthesized weight signal data sequences R ₀ , R ₁ ,..., R _n−1 can be obtained as shown below. it can.

R ₀ : W _d00 , W _d10 , ..., W _dk0 R ₁ : W _d01 , W _d11 , ..., W _dk1 ... R _n-1 : W _d0.n-1 , W _d1.n-1 ,..., _{Wdk.n-1 The} above processing is _executed by the CPU 12 in steps S206 and S208.
Do with.

Next, the n synthesized weight signal data strings R₀,
R₁, ..., R_n-1Standard deviation of each
) To calculate the composite weight signal data that minimizes the standard deviation.
Row R _M(In the example of FIG. 1, R_Two) Is selected by the selection means
(S210). Then, the CPU 12 determines that the standard deviation is the minimum.
The composite weight signal data sequence R_TwoCalculate the average value of
Average value corrected weight signal R_MH(S21)
2, S214). Corrected weight signal R_MHIs a periodic oscillation
From the uncorrected weight signal W on which the wave N is superimposed, its periodic oscillation wave
This is a signal from which N has been effectively removed.

According to the weighing device of this embodiment, as in the conventional weighing device, the rotation cycle detecting sensor for reading the synchronization signal of the periodic oscillation wave N and the synchronization signal are supplied to the CPU 12.
Automatically determine the phase of the noise data sequence that can effectively remove the noise data sequence superimposed on the weight data sequence without providing an input device for inputting the weight data sequence, and generate the corrected weight signal _RMH . be able to. Since the second constant-period vibration wave removing filter having a relatively large time constant is not used during the _{actual operation} , the delay of the response of the corrected weight signal RMH to the weight signal W before correction is shortened as compared with the conventional case. Thus, the weighing speed can be increased.

It should be noted that the combined weight signal data sequence R ₂ having the smallest standard deviation is such that the noise data sequence stored in the storage unit 14 has a phase difference of 180 degrees with respect to the noise data sequence superimposed on the weight data sequence. since the value of the sequence when calculating the sum of both shifted so that the most effective noise this combined weight signal data string R ₂ is removed.

Next, during the actual operation, the weighing conveyor 1
In the case where the rotation speed of the first motor 6 provided is changed, the period, amplitude, or waveform of the periodic oscillation wave signal N is different from those stored in the adjustment mode and those stored in the main operation mode. That is, if the noise data N stored in the adjustment mode is used as it is, the changed periodic vibration wave cannot be effectively removed from the uncorrected weight signal W obtained during the actual operation. Therefore, the correction unit of the CPU 12 performs a predetermined correction process on the noise data string of the periodic oscillation wave signal N stored in the storage unit 14 in the adjustment mode, thereby effectively removing the changed periodic oscillation wave. Explain how you can. The correction means is CP
U12, according to a predetermined program stored in the storage unit 14, determines the period and amplitude of the periodic oscillation wave N. The rotation speed information V (before change) of the first motor 6, which is the periodic oscillation wave source, Using V _X (after change), the storage unit 14
For correcting the noise data N stored in the.

Now, the fixed-period oscillation stored in the storage unit 14 will be described.
As shown in FIG. 2A, the noise data sequence of the motion wave signal N is
The cycle is T, and the rotation of the first motor 6
The rotation speed is reduced and the period becomes T as shown in FIG._XWhen
And the cycle T_XHow to calculate the noise data sequence
explain. Of the noise data stored in the storage unit 14
The number is n (= T / t₁), The data after the speed change
The data time interval is t_X= T_X/ N. Also noise
The amplitude of the data is proportional to the square of the rotation speed of the first motor 6.
Adjustment mode because it changes as an example (vertical component of centrifugal force)
And the rotational speed of the first motor 6 during the actual operation is V,
V_XThen, each noise data stored in the storage unit 14 is
Data W₀~ W_n-1To (V_X/ V)^TwoMultiply by
Rotation speed V after the change_XNoise data at
W_Z0~ W_Zn-1Can be calculated. Therefore, adjustment
The noise data string N stored in the mode is shown in FIG.
As shown in (a), the data time interval is t₁And
Each time t₀~ T_n-1Noise data at W₀~ W
_n-1Then, the correcting means converts the noise data sequence N
As shown in FIG. 2 (b), the data time interval is t_XIn
Time t_Z0, T_Z1, ..., t _Zn-1Neu in
Data is W_Z0, W_Z1, ..., W_Zn-1Noise Day
Row N_XAnd can be stored in the storage unit 14.
You. Where t_Z1-T_Z0= T_Z2-T_Z1= ... · = t
_Zn-1-T_Zn-2= T_XW_Z0= (V_X/ V)^Two× W₀,
W_Z1= (V_X/ V)^Two× W₁, ..., W_{Zn- 1}=
(V_X/ V)^Two× W_n-1It is.

By the way, of the weight signal W before correction during the actual operation,
The sampling time interval is t₁Therefore, the noise removal performance
To perform the calculation, the noise data sequence N_XThe sampling time
Interval t₁Since it is necessary to convert to each data,
The means uses an interpolation method to generate the noise data sequence N_XThe time
The interval is t₁(Time t₀, T₁, ..., t_k-1, T_k)of
Noise data string N_Y(Noise data value W_Y0, W_Y1, ...
・ 、 W_Yk-1, W_Yk) And stored in the storage unit 14.
Can be made. That is, as shown in FIG.
One cycle T_XAt time t₀, T₁, ..., t _k-1, T_kTo
Noise data W divided at each time_Y.0,
W_Y.1, ..., W_Yk-1, W_YkTo calculate the storage unit 1
4 is stored. For example, the time t shown in FIG._Zn-2
And t_Zn-1Time t between_k-2, T_k-1Noise de
Data W_Yk-2, W_Yk-1Explain when to ask for
You. As shown in FIG. 3, first, at time t_Zn-2And t_Zn-1
Of noise data y at W_Zn-2And W_Zn-1Directly
Connect with a line. When this straight line p is expressed by the equation of xy, y = − ｛(W_Zn-2-W_Zn-1) / T_x｝ × x + W_Zn-2 (1) Where t_Zn-2-T_Zn-1= T_xAnd This
Where x = t_k-2-T_Zn-2Into the equation (1)
t_k-2Noise data value W at_Yk-2, Y = W_Yk-2=-｛(W_Zn-2-W_Zn-1) / T_x｝ ×
(T_k-2-T_Zn-2) + W_Zn-2 Becomes Thus, each time t₀, T₁, ...,
t_k-1, T_kNoise data value W at_Y0, W_Y1, ...
・ 、 W_Yk-1, W_YkCan be requested. The figure
In Section 2, one cycle of the noise data has been described.
The storage unit 14 stores two cycles of noise data.
Therefore, the noise data for two cycles is changed in the same manner as above.
Can be exchanged.

However, the rotation speed of the first motor 6 is
Accelerate while working V_XNoise data sequence when> V
N_XHas a waveform as shown in FIG._X<
As in the case of V, the correction means is shown in FIG.
Each time t₀~ T_n-1Noise data value W at₀~ W
_n-1At each time t₀, T₁, Noise day at
Data value W_Y0, W_Y1, ... (see FIG. 2 (c))
be able to. Then, the sampling shown in FIG.
Time interval t₁If the time is short enough,
t₀~ T_n-1Noise data value W at₀~ W_n-1To
Then, without performing the conversion operation as described above,
In each case, each time t₀~ T _kTime t closest to
_ZmNoise data value W at_Y0~ W_YkEven if you apply
Good. m is an integer from 0 to n-1. For example,
Time t₁, T_TwoW as the noise data value of_Z1Apply
Time t_Three, T_FourW as the noise data value of_Z2Guess
Can be fitted.

Next, a weighing device according to a second embodiment will be described. The weighing device according to the second embodiment is the same as the weighing device according to the first embodiment, except that a phase difference changing unit, a composite weight signal calculating unit,
A phase difference detecting means and a synthetic weight signal calculating means in place of the selecting means. Other than this, since it is equivalent to the first embodiment, detailed description of the equivalent parts will be omitted. Each processing performed by the phase difference detecting means and the composite weight signal calculating means of the second embodiment is performed by the CPU 12 according to a program stored in the storage unit 14.

As shown in FIG. 9, the phase difference detecting means detects the times R to Q of the weight signal W before correction obtained during the actual operation.
Weight data columns in the _{W -R, ···, W -1,} W 0,
₁ stored in the storage unit 14 with W ₁ ,..., W _k
The noise data string W _Z0 of the periodic oscillation wave signal shown in FIG.
This is a means for detecting the phase difference between the two based on W _Z1 ,..., W _Zn-1 . The time interval T _N between times R and Q is
T (one cycle) / 2 or more. The weight signal W before correction after the time Q indicated by a broken line in FIG. 9 is for explaining the waveform of the weight signal W before correction and the cycle T of vibration. The synthetic weight signal calculating means calculates the weight data string W _{-R,.
··, W -1, W 0,} W 1, ···, W k and the noise data string W _Z0, W _Z1, ···, in a state in which the phase difference is 0 ° W _Zn-1, P~ Weight data strings W ₀ , W ₁ ,
···, W _k (weight data at time P to Q) and noise data string W _Z0, W _Z1, ···, by subtracting the noise data from the weight data of the timing corresponding to each other of W _Zn-1 synthesis by weight It is a means for calculating a signal.

According to the weighing device of the second embodiment, the actual operation
In the previous adjustment stage, the data of the periodic oscillation wave signal N was recorded.
The procedure stored in the storage unit is the procedure shown in FIG. 7 of the first embodiment.
Therefore, the description is omitted. Next, go live
In the state, steps S200 and S202 shown in FIG.
A process equivalent to the process of is performed. Then, the CPU 12 determines in FIG.
Where the periodic oscillation wave N in the designated sections R to Q shown in FIG.
Weight data string W of front weight signal W_-R~ W₀~ W_kA
/ D sampling time interval t₁Read in and write in chronological order
It is stored in the storage unit 14. And the weight data W_-R~ W₀~
W_kIs calculated by differentiating the maximum and minimum values and the corresponding weight data.
Data. If the detected weight data is
The determination as to whether the value is the minimum value is made, for example, by using the detected weight data.
By comparing the size of the weight data before and after
Can be determined. Next, the weight data string W_-R~ W
₀~ W _kData of the maximum value or the minimum value of
Then, the minimum value weight data W_-STiming and Figure 1
The noise data W of the minimum value of the noise data N shown in FIG.
_KCompare the timing of the two weight data strings
And the noise data sequence are calculated. Like this
To calculate the phase difference between the weight and noise data strings.
It is a phase difference detecting means. And a synthetic weight signal calculating means.
Is based on the calculated phase difference.
The two data are made to correspond so that the phase difference becomes 0 degree,
From weight data at the timings corresponding to each other
Subtract data to calculate composite weight signal
You. In this manner, as in the first embodiment, the periodic oscillation is performed.
Periodic vibration wave signal from weight signal W before correction including motion wave signal N
Generate a corrected weight signal with noise removed
Can be The phase difference detection means, and
The phase difference between the two data strings becomes 0 degree based on the phase difference
8. The method according to claim 7, wherein the two data are made to correspond to each other.
Means for changing the phase difference.

Incidentally, the weight data sequence W _-R ~W ₀ ~W _k acquisition start time R that is used to detect a phase difference, FIG. 9
As shown in, than acquisition start point P of the weight data sequence W ₀ to _W-k to be used for calculating the synthetic weight signal Yes in the previous timing (time), and further, the time interval R~Q noise The acquisition start time point R is set so as to acquire the weight data in the area of T (one cycle) / 2 or more of the data N. As a result, it is possible to always obtain the maximum value or the minimum value of the weight data from the weight data of the regions R to Q, and use the weight data strings W _{-R to} W _{0 to} W _k before correction. The phase difference between the weight signal W and the periodic vibration wave signal N can be accurately detected. Further, since the weight data between R and Q shown in FIG. 9 is in a transient state and has a relatively large attenuation degree, if this weight data is used for calculating the composite weight signal data, a weight error will be large. However, when calculating the phase difference, it is only necessary to detect data representing the maximum value or the minimum value from the weight data between R and Q, so the weight data between R and Q is used. I use it because there is no problem.

However, the method of converting the amplitude of the noise data value by the correction means of the above-described embodiment is based on the method of converting each noise data value W
_{0 to} W _n-1 are multiplied by (V _X / V) ² to obtain W _{Z0 to} W
_{The Zn- 1} was calculated. However, if the speed variable range of the first motor 6 is narrow, or if the fluctuation characteristic equation of the noise amplitude with respect to the rotation speed is complicated or unknown, the above method is used. Instead, the maximum amplitude and the minimum amplitude of the noise at the highest speed and the lowest speed in the speed variable range are measured and stored in the storage unit 14, and the amplitude at each speed within the variable range is calculated as the maximum amplitude and the minimum amplitude. May be obtained as an approximate value using a straight line connecting

Further, in the above-described embodiment, an example has been described in which the noise data string N of the periodic oscillation wave N is stored in the storage unit 14 at the time of the zero adjustment in the adjustment stage before the actual operation. For weighing devices that perform adjustments automatically or manually,
At the time of zero adjustment during the actual operation, the noise data sequence N may be read in the same manner as in the above embodiment, and may be replaced with the previously stored noise data sequence N and stored in the storage unit 14. As described above, when the noise data sequence N is stored in the storage unit 14 at the time of the zero adjustment during the actual operation, the noise data sequence N at the rotation speed of the first motor 6 at that time can be stored. Therefore, the conversion operation of the noise data string N by the correction means can be omitted. Then, even if not only the period and amplitude of the periodic oscillation wave N change during the actual operation, but also the periodic oscillation wave N after the change.
It is possible to obtain an accurate noise data sequence N _X of
It is possible to obtain a more accurate noise data sequence N _X than in the case of conversion by the correction means. Periodic vibration wave N during actual operation
Is changed when the rotation phases of the driving pulley 3 and the driven pulley 4 of the weighing conveyor 1 are shifted.
Since the driving pulley 3 and the driven pulley 4 are connected by the conveyor belt 5, slippage occurs between the pulleys 3, 4 and the conveyor belt 5, and the phases of the periodic oscillations generated by the rotation of the pulleys are shifted. As a result, the waveform of the periodic vibration wave N as the entire measuring conveyor 1 changes.

In the above embodiment, the first motor
Storage unit 14 stores the periodic oscillation wave N generated based on the rotation of
To remove the vibration wave N from the weight signal W before correction.
However, instead of this, the rotation of the first motor 6 is performed.
The periodic vibration wave N generated based on the rotation and the second motor 16
Storage unit for storing both periodic vibration waves M generated based on the rotation of
14, the two signals are obtained from the weight signal W before correction.
May be removed. like this
In the weighing device configured as described above, each of the periodic oscillation waves N and M
The first and second noise data are stored in the storage unit 14.
There is a need. That is, steps S200 to S200 shown in FIG.
At 204, the first motor based on the rotation of the first motor 6
When the noise data sequence is stored in the storage unit 14, the second
With the motor 16 stopped, the same as in the above embodiment is performed.
Then, the first noise data sequence is stored in the storage unit 14. Soshi
A second noise data based on the rotation of the second motor 16.
When storing the motor train in the storage unit 14, the first motor 6
After stopping, the second noise
The storage data sequence is stored in the storage unit 14. Next, the weight before correction
A step is performed to remove the first noise data from the signal W.
Steps S206 to S210 are performed and the standard deviation is minimized.
The composite weight signal data sequence R _iThe selection means selects
(S210). Next, the composite weight signal data sequence R_iCorrect
As the pre-weight signal data sequence, a second node
Steps S206 to S21 to remove noise data
0, and the newly obtained composite weight signal data string
U₀~ U_n-1Of which the standard deviation is the smallest
Signal data string U_jIs selected by the selection means (S210).
Then, the CPU 12 determines that the synthesized weight signal at which the standard deviation is minimized.
No. data string U_jCalculated the average value of and corrected this average value
Only weight signal U_MH(S212, S21
4). Corrected weight signal U_MHIs two periodic oscillation waves
From the uncorrected weight signal W on which N and M are superimposed, its periodic oscillation
This is a signal from which the waves N and M have been effectively removed.

Further, the composite weight signal calculating means of the first embodiment comprises a weight data sequence W ₀ -W _{k of the} weight signal W before correction shown in FIG. 1B and a noise data sequence W shown in FIG. _Z0 ~
_{WZ.n -1} is added to the resultant weight signal data sequence _{R0 to} Rn _-1.
It is configured to calculate a, instead of this, calculates the combined weight signal data sequence S ₀ ~S _n-1 by subtracting the noise data string W _Z0 ~W _Zn-1 from the weight data sequence W ₀ to _W-k It is good also as a structure which performs.

Then, the composite weight signal calculating means of the second embodiment calculates the weight data strings W _-R , ..., W _-1 , W ₀ ,
W ₁ ,..., W _k and noise data strings W _Z0 , W _Z1 ,.
The noise data was subtracted from the weight data at the timings corresponding to each other in the state where the phase difference of W _{Z. n-1} was 0 degree, and the composite weight signal was calculated. W _-R , ..., W _-1 , W ₀ , W ₁ , ...
.., W _k and noise data strings W _Z0 , W _{Z1 ,.
The} combined weight signal may be calculated by adding the weight data and the noise data at the timings corresponding to each other when the phase difference of _Zn-1 is 180 degrees.

Further, in the above embodiment, the periodic oscillation wave N
Noise data string W _Z0 of the two periods ~W _Zn-1, W _Z0 ~W
_{Although Zn-1} is stored in the storage unit 14, one cycle of the noise data strings _{WZ0 to} WZn _-1 may be stored in the storage unit 14 instead. In this case, the noise data string W for one cycle
_Z0 to _W-Zn-1 every time the shifting by the sampling time interval t ₁ to the weight data sequence W ₀ to _W-k, the head of the noise data W _Z0, the ... last noise data W _Zn-1,
.. Are sequentially repeated, so that noise data and weight data at corresponding times can be added. The weight data string W
₀ ~W _k number of noise data column W of the data of _Z0 ~W _Zn-
If larger than the number of data for _one of the one period, the number of noise data is the same as the number of weight data to or noise data string of plural periods to be larger storage section 14
To memorize.

Then, the selecting means in the above embodiment is the same as that shown in FIG.
In step S210 shown in, it calculates the n-number of combining weight signal data R ₀ to R _n-1 of the respective standard deviation, was chosen combining weight signal data string R _M standard deviation is minimized, instead of this Thus, n pieces of synthetic weight signal data R ₀ to
Calculates the difference between respective maximum and minimum values of R _n-1, may be selected synthetic weight signal data string R _M where the difference is minimum.

[0051]

According to each of the first to fifth aspects of the present invention, the combined weight signal selected by the selection means is stored in the storage unit in advance with the fixed-period vibration wave signal superimposed on the uncorrected weight signal. Calculated when the phase difference with the fixed period vibration wave signal becomes 180 degrees or 0 degree, and corrected by removing the noise that is the fixed period vibration wave signal by selecting this composite weight signal A weight signal can be generated.
Therefore, the rotation cycle detection sensor and the input device for inputting the synchronization signal to the CPU, which are required in the conventional fixed-period vibration wave removal method, can be omitted, and the cost can be reduced accordingly. These mounting spaces can be made unnecessary. Then, since the latter is removed from the former by superimposing the periodic oscillatory wave signal superimposed on the weight signal before correction and the periodic oscillatory signal stored in the storage means, the acquisition of the weight signal before correction is performed. Even if the section is shorter than one period of the periodic oscillation wave, the periodic oscillation wave can be accurately removed from the weight signal before correction. Thereby, high-speed weighing with high accuracy can be realized.

According to the second aspect, the delay of the response of the output signal to the input signal can be reduced as compared with the conventional case,
As a result, the weighing speed can be increased, so that the present invention can be applied to a weight sorter or the like that requires a relatively short weight value calculation signal acquisition section and requires high-speed weighing. According to the third aspect, the periodic oscillation wave signal stored in the storage unit can be corrected to a signal corresponding to the periodic oscillation wave when the speed of the periodic oscillation wave source changes. Therefore, even if the period and amplitude of the periodic oscillation wave superimposed on the weight signal before correction changes due to a change in the speed of the periodic oscillation wave source, it is possible to accurately remove the periodic oscillation wave after the change. it can.

According to the fourth aspect of the present invention, the constant period vibration wave is stored in the storage means at the time of zero point adjustment, so that the operating condition of the constant period vibration wave source changes and the constant period vibration wave is superimposed on the weight signal before correction. Even if the period, amplitude, and waveform of the vibration wave change,
The periodic oscillation wave after this change can be accurately removed. Since the periodic oscillation wave is stored in the storage means at the time of zero adjustment, the operating time of the weighing device is not reduced. According to the fifth aspect, when performing the zero adjustment, the zero adjustment can be performed using the corrected weight signal from which the periodic oscillation wave has been removed, so that the accurate zero adjustment of the weight signal can be performed. it can. When the periodic oscillation wave is stored in the storage means, the periodic oscillation wave to be superimposed on the zero-adjusted weight signal before correction can be stored, so that the noise component that is the periodic oscillation wave is accurately stored. can do. According to the sixth aspect, even when two or more periodic vibration waves are superimposed on the weight signal before correction, the first
Similarly to the effect of the invention, the rotation cycle detection sensor and the like can be dispensed with, and high-speed weighing with high accuracy can be realized.

According to the seventh and eighth aspects of the present invention, the combined weight signal calculated by the combined weight signal calculating means is stored in advance in the storage unit together with the periodic oscillation wave signal superimposed on the uncorrected weight signal. Calculated when the phase difference with the fixed-period vibration wave signal is changed to 0 degree or 180 degrees or an angle close to it, and generates a corrected weight signal from which noise, which is a fixed-period vibration wave signal, has been removed. can do. Therefore, an effect equivalent to that of the first invention can be achieved.

According to the ninth aspect, even when it is not possible to secure a long time for acquiring the uncorrected weight signal used for calculating the composite weight signal, the uncorrected weight signal used for detecting the phase difference is used. By obtaining the acquisition start time before the acquisition start time of the uncorrected weight signal used to calculate the composite weight signal, it is possible to obtain a large amount of data of the uncorrected weight signal. Is used, it is possible to accurately detect the phase difference between both the weight signal before correction and the periodic wave signal.

[Brief description of the drawings]

FIG. 1 shows various data stored in a storage unit of a weighing device according to a first embodiment of the present invention, wherein (a) is noise data of a periodic vibration wave, and (b) is weight data of a weight signal before correction. (C) is a diagram showing combined weight signal data, and (d) to (f) are diagrams showing combined weight signal data when noise data is sequentially shifted.

FIGS. 2A and 2B are various data stored in a storage unit of the weighing device according to the embodiment, wherein FIG. 2A shows noise data of a periodic oscillation wave, and FIG. 2B shows noise after conversion when the period becomes long. FIG. 9C is a diagram showing noise data after conversion when the cycle is shortened.

FIG. 3 is a diagram for describing correction of noise data by the correction unit of the embodiment.

FIG. 4 is a diagram showing a weighing conveyor and a feeding conveyor provided in the weighing device according to the embodiment.

FIG. 5 is a block diagram showing an electric circuit of the weighing device according to the embodiment.

FIG. 6 is a diagram for explaining calculation of an average value of noise data by the weighing device according to the embodiment.

FIG. 7 is a flowchart showing a procedure for storing noise data of a periodic oscillation wave signal by the weighing device according to the embodiment.

FIG. 8 is a flowchart showing a procedure for removing a periodic oscillation wave from the weight signal before correction by the weighing device according to the embodiment.

FIG. 9 is a view used to explain a weighing device according to a second embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 Weighing conveyor 2 Load cell 3 Drive pulley 6 First motor 12 CPU 14 Storage unit

Claims (9)

[Claims] 1. A weighing device for generating a corrected weight signal by removing said fixed-period vibration wave from a pre-correction weight signal on which a fixed-period vibration wave is superimposed in an operation state, wherein the fixed-period vibration wave has at least one period. Storage means for storing the minute signal, and phase difference changing means for sequentially changing the phase difference between both the uncorrected weight signal output by the load detection means and the periodic oscillation wave signal stored in the storage means. A combined weight signal calculating means for adding the uncorrected weight signal and the periodic vibration wave signal for each of the plurality of phase differences or subtracting the other from one to calculate a combined weight signal for each phase difference,
Selecting means for selecting a composite weight signal having a relatively small signal variation or a difference between a maximum value and a minimum value from among the plurality of composite weight signals. 2. The weighing device according to claim 1, wherein the phase difference changing unit is configured to store the pre-correction weight signal in a predetermined weight value calculation signal acquisition section in the constant period oscillation stored in the storage unit. The phase of the wave signal is set to 1
A weighing apparatus characterized in that the phase difference between the two is sequentially changed by relatively shifting by a predetermined time shorter than the cycle time. 3. The fixed-period vibration according to claim 1, wherein the constant-period vibration stored in the storage means is based on velocity information of a fixed-period vibration wave source for determining a period and an amplitude of the fixed-period vibration wave. A weighing device comprising correction means for correcting a wave signal. 4. The weighing device according to claim 1, wherein a signal for at least one cycle of the periodic oscillation wave is stored in the storage unit when the weight signal is zero-adjusted. . 5. The weighing device according to claim 1, wherein a fixed-period vibration wave superimposed on the uncorrected weight signal is removed by a fixed-period vibration wave removal filter, and the corrected weight signal obtained by this is removed. A switching means for switching between a switching position at which zero point adjustment is performed by the zero point adjusting means and a switching position at which the periodic oscillation wave superimposed on the zero-corrected weight signal before correction is stored in the storage means. A weighing device characterized by the following. 6. A load detector in which first and second two periodic vibration waves are superimposed on a weight signal before correction, wherein a first periodic vibration wave is generated to generate a first periodic vibration wave. Storing a signal for at least one period, generating a second periodic vibration wave and storing a signal for at least one period of the second periodic vibration wave, and storing the first and second constant periods The phase difference between the uncorrected weight signal on which the vibration wave is superimposed and the stored first constant-period vibration wave signal is sequentially changed, and the uncorrected weight signal and the first constant value are output for each of the plurality of phase differences. Adding a periodic oscillation wave signal or subtracting one from the other to calculate a first combined weight signal for each phase difference; and among the plurality of first combined weight signals, signal variations or maximum and minimum values. Selecting a second composite weight signal having a relatively small value difference; The phase difference between the weight signal and the stored second fixed-period vibration wave signal is sequentially changed, and the second combined weight signal and the second fixed-period vibration wave signal for each of the plurality of phase differences are added. Or calculating a third combined weight signal for each phase difference by subtracting the other from one,
Selecting a fourth synthesized weight signal having a relatively small signal variation or a difference between a maximum value and a minimum value from among the synthesized weight signals. 7. A weighing device for generating a corrected weight signal by removing said fixed-period vibration wave from a weight signal before correction on which a fixed-period vibration wave is superimposed in an operating state, wherein at least one period of said fixed-period vibration wave is provided. Storage means for storing the minute signal, and the phase difference between the two based on the pre-correction weight signal output by the load detection means and the periodic vibration wave signal stored in the storage means, 0 degrees or 180 degrees, Or a phase difference changing means for changing the angle to an angle close thereto, and calculating a combined weight signal of the uncorrected weight signal and the fixed-period vibration wave signal at a phase difference of 0 or 180 degrees or an angle close thereto. A composite weight signal calculating means for generating a corrected weight signal from which the periodic vibration wave has been removed. 8. A weighing device that generates a corrected weight signal by removing said periodic vibration wave from a pre-correction weight signal on which a periodic vibration wave is superimposed in an operating state, wherein the periodic signal has at least one period. Storage means for storing a minute signal, and phase difference detection means for detecting a phase difference between the two based on the uncorrected weight signal output from the load detection means and the periodic oscillation wave signal stored in the storage means. And the phase difference between the weight signal before correction and the periodic oscillation wave signal is set to 0.
A combined weight signal calculating means for calculating a combined weight signal in a state where the angle is 180 degrees or 180 degrees or an angle close thereto and generating a corrected weight signal from which the periodic oscillation wave is removed. And a weighing device. 9. The weighing device according to claim 8, wherein the acquisition start time of the pre-correction weight signal used by the phase detecting means for detecting a phase difference is determined by the composite weight signal calculating means. A weighing device, which is earlier than the acquisition start time of the uncorrected weight signal used for calculating the signal.