JP4541088B2 - Combination weighing device - Google Patents

Description

  The present invention relates to a combination weighing device having a self-diagnosis function.

  In the conventional combination weighing device, for example, a plurality of supply hoppers to which the objects to be weighed are supplied are arranged, and a weighing hopper to which the objects to be weighed are fed from the supply hopper is arranged below each supply hopper. Each weighing hopper is equipped with a weight sensor such as a load cell. The weight sensor measures the weight of the object to be weighed in the weighing hopper, and the weight of the object to be weighed is within a predetermined weight range by combination calculation. A combination is obtained, and the objects to be weighed are discharged from the weighing hopper corresponding to the combination.

  In such a combination weighing device, for example, if the weighing hopper is defective and the gate does not close completely, the object to be weighed or its fragments may fall from the weighing hopper before being discharged after the combination calculation. . In addition, when there is a problem with the supply hopper and the gate does not close completely, the object to be weighed or a fragment thereof may fall from the supply hopper to the weighing hopper before being discharged after the combination calculation. Thus, if there is a problem with the weighing hopper or the supply hopper, and the weight of the weighing hopper selected in the combination calculation changes after the combination calculation, the total weight of the objects to be discharged becomes It may not be within the predetermined weight range. In addition, if the balance stabilization wait time that determines the timing for inputting the weight value used in the combination calculation from the weight sensor attached to the weighing hopper is not set to an appropriate time, accurate weighing will not be performed and In some cases, the total weight of the objects to be measured does not fall within the predetermined weight range.

  As a technique for dealing with such various problems, for example, there are those described in Patent Documents 1 to 5.

  In the technique described in Patent Document 1, in a semi-automatic combination weighing device in which a person directly inputs an object to be weighed into a weighing hopper, after a combination calculation, when a person mistakenly loads the object to be weighed into the weighing hopper selected for the combination. In order to prevent this from happening, the total weight of the objects to be discharged will be out of the predetermined weight range. To prevent this, the weights of the weighing hoppers selected for the combination are constantly added up to the discharge to check whether they are within the predetermined weight range Then, by recombining when the weight is out of the predetermined weight range, the total weight of the objects to be discharged is prevented from being out of the predetermined weight range. It is also described that the present invention can be applied to an automatic combination weighing device that automatically supplies an object to be weighed to a weighing hopper.

  Further, the technique described in Patent Document 2 detects the weight of the weighing hopper again after a predetermined time has elapsed since the operation command signal for discharging the object to be weighed is output from the weighing hopper, that is, after discharging. This is to check for malfunctions.

  The technique described in Patent Document 3 stores the combination weight value and the combination pattern of the discharged weighing hopper when discharging the objects to be weighed from the combination weighing device, and measures the discharged weight with an external scale. If it does not match the combination weight value stored in the combination weighing device, the combination pattern is accumulated, and it is specified that there is a problem in the weighing hopper showing the peak value.

  In addition, the technique described in Patent Document 4 detects the weight of the weighing hopper again after discharging the object to be weighed from one chamber of the weighing hopper divided into two chambers, and determines whether or not it has actually been discharged. Check to determine whether the weighing hopper is abnormal.

The technique described in Patent Document 5 stores the measurement value of the weighing hopper that participated in the combination calculation but was not selected for the combination, and the stored value is the same as the measurement value measured in the next measurement cycle. It is checked whether they match, and checks whether the balance stabilization waiting time is appropriate.
Utility Model Registration No. 2565169 Japanese Patent Publication No. 6-1212 JP-A-62-284211 Utility Model Registration No. 2575115 JP-A-7-43196

  When the technique described in Patent Document 1 is applied to an automatic combination weighing device, the weight of the weighing hopper selected for the combination is continuously added up to the discharge and recombined when the weight falls outside the predetermined weight range. Although it is possible to prevent the weight from deviating from the predetermined weight range, it is not possible to specify the cause (what trouble is present) that deviates from the predetermined weight range after combination calculation. Moreover, in each technique of patent documents 2-5, although the presence or absence of an individual defect can be checked, the presence or absence of multiple types of defects cannot be checked simultaneously.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a combination weighing device that can simultaneously check the presence or absence of a plurality of types of defects.

In order to solve the above problems, a combination weighing device of the present invention includes a plurality of supply hoppers, a plurality of weighing hoppers that are respectively disposed below the supply hoppers and into which objects to be weighed are fed from the supply hoppers, A plurality of weight detecting means provided corresponding to the weighing hoppers, weighing the weight of an object to be weighed in the weighing hopper, and outputting the measured value, and input from each of the weight detecting means. The combination calculation is performed based on the measured weight value to obtain a combination of the weighing hoppers in which the total weight value of the weight detection means is a value within a predetermined weight range, and the object to be weighed is discharged from the weighing hopper of the combination. A combination weighing device comprising: a control unit for controlling the weight detection unit to measure the weight value of the weight detection unit corresponding to the weighing hopper of the combination obtained by the combination calculation The combination weighing value that is a total is stored, and each weighing value at the time of combination that is the weighing value of the weight detection unit corresponding to each of all the weighing hoppers used in the combination calculation is stored. The weight detection unit corresponding to the weighing hopper of the combination obtained by the combination calculation after the combination calculation is performed and before the weighing object is discharged from the weighing hopper of the combination obtained by the combination calculation. A determination process for determining whether or not a difference between the total value and the combined measurement value is within an allowable error range. When the difference between the combined value and the combination weighing value does not fall within an allowable error range as a result of the determination, the weight detection means corresponding to each of all the weighing hoppers is performed. A measurement error process for obtaining and storing data indicating a magnitude relationship between each post-combination measurement value and each measurement value at the time of combination for each of the measurement hoppers; the metering error processing based on the data stored by gastric lines and processing for determining the presence or absence of the malfunction of a plurality of types, wherein the process of determining the presence or absence of the plurality of types of defects, recent multiple of the metering error When the data stored by the process is only data indicating that each measured value after combination is larger than each measured value at the time of combination for all weighing hoppers, or only data indicating that it is smaller, After the object to be weighed is fed from the supply hopper to the weighing hopper, the timing for inputting the weighing value used in the combination calculation from the weight detection means is determined. It is determined that the balance stabilization waiting time is set to an inappropriate time, and the data stored by the plurality of weighing error processings of the most recent times is the same after the combination for each weighing hopper. Except when there is only data indicating that it is larger than the weighing value and only when it is only data indicating that it is smaller, and the data stored by the plurality of recent weighing error processing is arbitrary When only the data indicating that each measured value after the combination is larger than each measured value at the time of the combination with respect to the first weighing hopper, the supply hopper disposed above the first weighing hopper It is determined that there is a defect, and the data stored by the plurality of recent weighing error processes is greater than the respective measured values at the time of combination for all the weighing hoppers. The data stored by the plurality of recent weighing error processes is the second weighing hopper except for the case where only the data indicating the data and the data indicating only the small data are excluded. In the case where only the data indicating that each measured value after combination is smaller than each measured value at the time of combination, it is determined that the second weighing hopper is defective, and the weighing error processing is performed a plurality of times recently. Except for the case where the data stored in the above are all data indicating that each post-combination measurement value is larger than each measurement value at the time of combination and only data indicating that the data is smaller for all weighing hoppers. In addition, the data stored by the plurality of recent weighing error processings is obtained from the respective weighing values after combination for any third weighing hopper. If it contains both data indicating data and a small showing a larger effect, it is determined that there is a defect in the metering unit including the third weighing hoppers and said weight detecting means associated thereto.

  According to this configuration, it is possible to simultaneously check the presence / absence of a plurality of types of defects based on the data stored by the weighing error process.

  The control means outputs a first abnormality signal when it is determined that the balance stabilization waiting time is set to an inappropriate time, and is disposed above the first weighing hopper. If it is determined that the supply hopper is defective, a second abnormality signal is output. If it is determined that the second weighing hopper is defective, a third abnormality signal is output. When the weighing unit including the weighing hopper and the weighing unit corresponding to the weighing hopper is determined to be defective, a fourth abnormality signal is output, and each of the first to fourth abnormality signals is output. It is preferable to provide an informing means for informing that there is a problem corresponding to.

  Thereby, it is possible to inform the operator what kind of trouble has occurred.

  Further, the control means determines whether or not the total value is within the predetermined weight range, and when the total value is not within the predetermined weight range, discards the combination by the combination calculation. It is preferable not to discard the combination by the combination calculation when the combination calculation is performed again and the combined value is a value within the predetermined weight range.

  In this way, when the combined value is not within the predetermined weight range, the combined calculation is performed again to prevent the total discharge weight from being out of the predetermined weight range, and the combined value is a value within the predetermined weight range. In this case, since there is no problem with the total weight to be discharged, it is not necessary to perform the combination calculation again by using the combination by the first combination calculation.

  The present invention has the above-described configuration, and produces an effect that a combination weighing device can simultaneously check for the presence or absence of multiple types of defects.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
(Embodiment)
FIG. 1 is a schematic diagram showing a configuration of a combination weighing device according to an embodiment of the present invention.

  In the combination weighing device according to the present embodiment, a conical dispersion feeder 11 is provided in the center of the upper portion of the device to disperse the object to be weighed supplied from the external supply device 10 radially by vibration. Around the dispersion feeder 11, linear feeders 12 are provided for feeding the objects to be weighed sent from the dispersion feeder 11 to the respective supply hoppers 13 by vibration. A plurality of supply hoppers 13 and weighing hoppers 14 are respectively provided below the linear feeder 12 and arranged in a circular shape. The supply hopper 13 receives the object to be weighed sent from the linear feeder 12, and when the weighing hopper 14 disposed below it is empty, the gate is opened and the object to be weighed is put into the weighing hopper 14. A weight sensor 15 such as a load cell is attached to the weighing hopper 14, and the weight sensor 15 measures the weight of an object to be weighed in the weighing hopper 14. When a combination of hoppers to be discharged is obtained from a plurality of weighing hoppers 14 by a combination calculation by the control unit 21 and a discharge request signal is input from a packaging machine or the like (not shown), the weighing hoppers 14 corresponding to the combination receive a measurement target. Objects are discharged onto the collecting chute 16. The collective chute 16 is provided below the weighing hopper 14, and a collective funnel 17 is disposed below the collective chute 14. In addition, a photoelectric level sensor 18 for detecting the amount of an object to be weighed on the dispersion feeder 11 is provided, and the control unit 21 sets the object to be weighed on the dispersion feeder 11 to a certain amount based on a signal from the level sensor 18. The supply device 10 is controlled to keep.

  The control unit 21 includes an I / O unit 210, a CPU 211, a memory 212, and the like. The control unit 21 controls the above-described supply device 10 and the entire combination weighing device, and performs combination calculation. In the combination calculation, a combination of hoppers in which the total of the measured values of the objects measured by the weight sensor 15 is within an allowable range (predetermined weight range) with respect to the target weight among the plurality of weighing hoppers 14. One is required. When there are a plurality of hopper combinations that satisfy the above-mentioned allowable range values, for example, one combination is selected from the plurality of combinations, for example, the sum of the measured values of the objects to be weighed is closest to the target weight. .

  An outline of the operation of the combination weighing device according to the present embodiment configured as described above will be described first. The operation of the combination weighing device is realized by the control of the control unit 21.

  First, the objects to be weighed are conveyed above the combination weighing device by the supply device 10 and placed on the dispersion feeder 11. Then, the objects to be weighed are sent to the supply hoppers 13 which are radially dispersed by the vibration of the dispersion feeder 11 and arranged in a plurality of circles via the linear feeder 12 following the dispersion feeder 11. When the weighing hoppers 14 located below the supply hoppers 13 are empty, the objects to be weighed in the supply hoppers 13 are put into the weighing hoppers 14. When the control unit 21 performs a combination calculation and inputs a discharge request signal from a packaging machine or the like, the control unit 21 opens and closes the gate of the weighing hopper 14 of the combination obtained by the combination calculation and discharges the objects to be weighed onto the collecting chute 16. The objects to be weighed are collected on the collecting chute 16 by the collecting funnel 17 and sent to a packaging machine or the like.

  Next, detailed operation of the combination weighing device in the present embodiment will be described. FIG. 2 shows a flowchart of the operation of the combination weighing device in the present embodiment. A combination completion flag, which will be described later, is set in a combination completion flag area in the memory 212. Moreover, the measurement value (measurement signal) from the weight sensor 15 is always output to the control unit 21, and the control unit 21 can read the measurement value when necessary.

  In step S1, it is checked whether or not the combination completion flag is set in the flag area. If the flag is not set, the combination is based on the measured value of the weighing object of each weighing hopper 14 measured by the weight sensor 15. A calculation is performed to obtain a combination of the weighing hoppers 14 to be discharged (step S2). Next, a combination completion flag is set (step S3), and each weighing value used in the above-described combination calculation for all the weighing hoppers 14 is stored in the memory 212 (step S4), and the combination pattern and the combination weight value are stored in the memory It memorize | stores in 212 (step S5). An example of the stored data at this time is shown in FIG. The combination pattern indicates the combination weighing hopper 14 obtained by the combination calculation, and the total of the measurement values of the objects to be weighed in the combination measurement hopper 14 is the combination weight value.

  In this way, when the combination calculation is performed and the combination completion flag is set, the process proceeds from step S1 to step S6, and it is determined whether or not the discharge request signal from the packaging machine or the like is input. If the discharge request signal is input, the gate of the weighing hopper 14 of the combination obtained by the combination calculation is opened and closed, and the object to be weighed is discharged (step S7). Then, the combination completion flag is cleared (step S8), and the respective measurement values, combination patterns and combination weight values for all the weighing hoppers 14 stored in the memory 212 in steps S4 and S5 are cleared (steps S9 and S10). ).

  If the discharge request signal from the packaging machine or the like is not input in step S6, the process proceeds to step S11, and the combination obtained by the combination calculation (combination pattern in the data of FIG. 4A stored in the memory 212). The weighing value is read from the weight sensor 15 for each of the weighing hoppers 14 and the total value is obtained. Next, in step S12, it is determined whether or not the difference between the sum obtained in step S11 and the combination weight value stored in the memory 212 is within the allowable error range. This allowable error is the maximum value of the expected measurement error including the influence of disturbances such as airflow. If the above difference is within the allowable error range, it is determined that there is no problem in the combination weighing device. Yes.

  If it is determined in step S12 that the difference between the combined value and the combined weight value is within the allowable error range, it is determined that there is no problem as described above, and a discharge request from the packaging machine or the like is requested. Steps S1, S6, S11, and S12 are repeated until a signal is input. If it is determined in step S12 that the difference between the combined value and the combined weight value is outside the allowable error range, the weight value from the weight sensor 15 for each of all the weighing hoppers 14 (hereinafter referred to as a comparative weighing value). Is read (step S13). An example of data read at this time is shown in FIG. Next, in step S14, for each weighing hopper 14, the difference between the comparative measurement value in FIG. 4B and the measurement value in the combination calculation in FIG. 4A (here, the comparison measurement value—the measurement in the combination calculation). Value) is obtained and stored in the memory 212 as the current measurement error data (step S13). An example of the stored data at this time is shown in FIG.

  Next, in step S15, a program for determining the cause of the malfunction based on the above-described measurement error data is executed. A flowchart of this program is shown in FIG.

  In FIG. 3, first, it is determined whether or not all recent weighing error data for all weighing hoppers 14 are positive values or all are negative values (step S31). When all of the plurality of recent weighing error data for the value is a positive value or a negative value, a warning that the balance stabilization waiting time is set to an inappropriate time is displayed (step S32). ). Here, the reason for determining that the balance stabilization waiting time is an inappropriate time will be described below. FIG. 5 shows a measurement signal (measurement value) waveform of the weight sensor 15 attached to the measurement hopper 14. The weight value used for the combination calculation is, for example, that of the weight sensor 15 read when the set balance waiting time has elapsed since the gate of the supply hopper 13 is opened to supply the weighing object to the weighing hopper 14. It is a measurement signal (measurement value). As shown in FIG. 5, the weighing signal of the weight sensor 15 fluctuates between time t1 and t2, that is, until the time ta elapses after the gate of the supply hopper 13 is opened at time t1, and then stabilizes. Therefore, when the balance stabilization waiting time is set to a time tb or tc shorter than the time ta, the measured value does not indicate an actual weight value. When the balance stabilization waiting time is set at time tb, the measured value becomes smaller than the actual weight value, and when set at time tc, the measured value becomes larger than the actual weight value. There are a plurality of weight sensors 15 depending on the number of weighing hoppers 14, but the waveforms until they are stabilized are almost the same. Since the measurement value read in step S13 performed while waiting for the discharge request signal after completion of the combination is considered to be read after the stabilization time ta has elapsed, for example, when the balance stabilization wait time is set to time tb In this case, the weighing error data for all the weighing hoppers 14 have a negative value, and the weighing error data for all the weighing hoppers 14 is a positive value when the balance stabilization waiting time is set to, for example, time tc. In either case, it can be said that the balance stabilization waiting time is too short to be appropriate. Even if the measured value read in step S13 is a measured value before the stable time ta has elapsed, the same result can be obtained. In step S32, a warning is displayed, but instead, it may be configured to automatically lengthen the balance stabilization wait time.

  If all of the recent plurality of weighing error data for all the weighing hoppers 14 are not a positive value or a negative value, the process proceeds to Step S33 and the subsequent steps, and the recent data for all of the n weighing hoppers 14 is updated. The weighing error data of a plurality of times is examined, and it is determined whether or not there is a defect related to each weighing hopper 14. When all the recent weighing error data for a certain weighing hopper 14 are positive values, a warning is displayed indicating that the supply hopper 13 disposed above the weighing hopper 14 is defective. (Steps S34 and S35). Here, the reason why it is determined that the supply hopper 13 is defective is that the supply hopper 13 is to be weighed from the supply hopper 13 until the measurement value is read in step S13 after the measurement value used in the combination calculation is measured. The reason for this is that the object has fallen and the weight has increased. This is because the gate is not completely closed due to a malfunction of the opening / closing device that opens and closes the gate of the supply hopper 13, and a gap is formed from the gap. Pieces of the weighing object fall, or the supply hopper 13 is poor, and there is a gap between the hopper body of the supply hopper 13 and the gate, and the piece to be weighed or the piece of the measurement object falls from the gap. Conceivable.

  Further, if all the recent weighing error data for a certain weighing hopper 14 are negative values, a warning message indicating that the weighing hopper 14 is defective is displayed (steps S38 and S39). Here, the reason why it is determined that the weighing hopper 14 is defective is that the object to be weighed falls from the weighing hopper 14 until the measurement value is read in step S13 after the measurement value used in the combination calculation is measured. This is because the weight of the weighing hopper 14 is considered to have decreased. As a cause thereof, a gate is not completely closed due to a malfunction of an opening / closing device that opens and closes the gate of the weighing hopper 14, and a gap is formed from the gap. It is conceivable that an object piece falls or the weighing hopper 14 is poor and there is a gap between the hopper body of the weighing hopper 14 and the gate, and an object to be weighed or an object to be weighed falls from the gap. It is done.

  In addition, when the weighing error data for a certain weighing hopper 14 includes both a positive value and a negative value, a warning message indicating that the weighing unit including the weighing hopper 14 has a problem is displayed. (Steps S40 and S41). Here, the reason for determining that the weighing unit including the weighing hopper 14 is defective is not the defect of the weighing hopper 14 as described above, but the failure of the weight sensor 15 such as the load cell connected to the weighing hopper 14 and the weighing. This is because there may be a failure in the parts constituting the weighing unit, such as a poor fitting in the metal fitting or the like to which the hopper 14 is attached.

  Further, when the determination in step S40 is no (No), that is, when the error data of a plurality of recent times for a certain weighing hopper 14 is all 0, 0 and a positive value, and 0 In the case of a negative value, the warning display related to the weighing hopper 14 is not performed.

  The warning display in steps S32, S35, S39, and S41 includes, for example, an operation setting indicator (not shown. For example, a touch panel) for operating the combination weighing device and displaying a set value such as an operation speed. ) To inform the operator.

  For example, in the case of examining the last two measurement error data as the plurality of recent measurement error data to be checked in steps S31, S34, S38, and S40, the current and previous data in FIG. What is necessary is just to refer, and when examining the measurement error data of the latest three times, what is necessary is just to refer to the data of this time of FIG. For example, in the steps S31, S34, S38, and S40, the latest three measurement error data are checked, and when the measurement error data as shown in FIG. 1-No. Warning that the balance stabilization waiting time in step S32 is inappropriate because all three weighing error data from the previous time to this time for all weighing hoppers of n are not positive values or all negative values. Is not displayed. And No. Since the three weighing error data from the previous time to the current weighing hopper of No. 1 are all positive values, no. A warning that there is a problem with the supply hopper disposed above the one weighing hopper is displayed (steps S34 and S35). No. Since the three weighing error data from the previous time to the current weighing hopper of No. 2 are all negative values, A warning that there is a problem with the weighing hopper 2 is displayed (steps S38 and S39). No. The three weighing error data from the previous time to the current time of 3 weighing hoppers are 0 (0.0) the previous time, a negative value (-0.1) the previous time, and a positive value (+0.1) this time. Yes, including both positive and negative values. A warning message indicating that the weighing unit including the weighing hopper 3 is defective is displayed (steps S40 and S41). No. Since the three weighing error data from the previous time to the current weighing hopper of n are all 0 (0.0), no. No warning display related to n weighing hoppers.

  After executing the discrimination program in step S15 as described above, in the next step S16, the sum value obtained in step S11 is a value within an allowable range (predetermined weight range) with respect to the target weight used in the combination calculation. It is determined whether or not. If the total value is not within the allowable range, the combination completion flag is cleared (step S17), and the respective measurement values, combination patterns, and combinations for all the weighing hoppers 14 stored in the memory 212 in steps S4 and S5. The weight value is cleared (steps S18 and S19), the process returns to step S1, and then proceeds to step S2 to perform the combination calculation again. In step S16, if the total value is within the allowable range, the process returns to step S1, and then proceeds to step S6. If the discharge request signal is input, the combination measurement obtained in the previous combination calculation is performed. The object to be weighed is discharged from the hopper 14 (step S7), and if the discharge request signal is not input, the processing from step S11 is performed again in order. As described above, the processing from step S11 is sequentially performed again, and when the processing of step S14 is performed, the measurement error data calculated at this time is newly stored as the current measurement error data and previously stored. This time, the previous measurement error data becomes the previous measurement error data. Therefore, if a series of operations in which a combination operation is performed and discharged from the weighing hopper is defined as one weighing cycle, the weighing error data of this time, the previous time,... In FIG. Some may be stored in the cycle, and some may be stored in the same weighing cycle (for example, previous and current weighing error data may be stored in the same weighing cycle). In the discrimination program (step S15) of FIG. 3, the determination is made using the latest measurement error data of a plurality of times, and the latest measurement error data of a plurality of times used at this time is stored in different measurement cycles. Even those stored in the same weighing cycle may be used.

  As described above, according to the present embodiment, it is possible to simultaneously check for the presence or absence of a plurality of types of defects such as a balance stabilization waiting time failure (lack of set time), a supply hopper failure, a weighing hopper failure, and a weighing unit failure. If there is a defect, the contents of the defect can be displayed as a warning to notify the operator.

  In this embodiment, in step S14 in FIG. 2, for each weighing hopper 14, the difference between the comparative measurement value in FIG. 4B and the measurement value in the combination calculation in FIG. 4A (comparative measurement value). -Weighing value at the time of combination calculation) is obtained as weighing error data, and it is determined in steps S31, S34, S38, and S40 in FIG. 3 whether the weighing error data is a positive value or a negative value. However, in step S14 of FIG. 2, instead of the above-described measurement error data, data indicating the magnitude relationship (including equivalent) between the comparison measurement value and the measurement value at the time of the combination calculation is obtained, and the data is used to obtain the figure. In step S31, S34, S38, and S40, the magnitude relationship between the comparative measurement value and the measurement value at the time of combination calculation may be determined.

  The present invention is useful as a combination weighing device having a self-diagnosis function for a plurality of types of defects.

It is a schematic diagram which shows the structure of the combination weighing | measuring apparatus in embodiment of this invention. It is a flowchart of operation | movement of the combination weighing | measuring apparatus in embodiment of this invention. It is a flowchart of the discrimination program of the combination weighing device in the embodiment of the present invention. It is a figure which shows an example of the data memorize | stored in memory in embodiment of this invention. It is a figure for demonstrating the reason for the balance stabilization waiting time becoming inappropriate in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Supply apparatus 11 Dispersion feeder 12 Linear feeder 13 Supply hopper 14 Weighing hopper 15 Weight sensor 16 Collecting chute 17 Collecting funnel 18 Level sensor 21 Control part

Claims (3)

A plurality of supply hoppers;
A plurality of weighing hoppers that are respectively disposed below the supply hopper and into which an object to be weighed is fed from the supply hopper;
A plurality of weight detection means provided corresponding to each of the weighing hoppers, weighing the weight of an object to be weighed in the weighing hopper, and outputting the measured value;
By performing a combination calculation based on the measurement values input from the respective weight detection means, a combination of the weighing hoppers in which the total of the measurement values of the weight detection means is a value within a predetermined weight range is obtained. A combination weighing device comprising control means for discharging an object to be weighed from the weighing hopper,
The control means stores a combination weighing value that is the sum of the weighing values of the weight detection means corresponding to the weighing hopper of the combination obtained by the combination calculation, and each of all the weighing hoppers used in the combination calculation. Each weight value at the time of combination that is a weight value of the weight detection means corresponding to
Further, the control means, after performing the combination calculation, before discharging the object to be weighed from the weighing hopper of the combination obtained by the combination calculation,
The weight value of the weight detection means corresponding to the weighing hopper of the combination obtained by the combination calculation is input to obtain the sum of these weight values (hereinafter referred to as the sum value), and the sum of the sum value and the combination weight value While repeatedly performing a determination process for determining whether the difference falls within the allowable error range,
As a result of the determination, when the difference between the combined value and the combination weighing value is not within the range of the allowable error, each post-combination measurement value that is a measurement value of the weight detection unit corresponding to each of all the weighing hoppers Measurement error processing for obtaining and storing data indicating the magnitude relationship between each measured value after combination and each measured value at the time of combination for each of the weighing hoppers,
There lines and processing for determining the presence or absence of the failure of a plurality of types based on the data stored by the metering error processing,
The process of determining the presence or absence of the plurality of types of defects is as follows:
Indicates that the data stored by the plurality of recent weighing error processes is only data indicating that each combined weighing value is larger than each weighing value at the time of combination for all weighing hoppers or is small. In the case of only data, after the object to be weighed is fed from the supply hopper to the weighing hopper, the weighing stability waiting time for determining the timing for inputting the weighing value used in the combination calculation from the weight detecting means is inappropriate. The time is set to
Data indicating that the data stored by a plurality of recent weighing error processes is only data indicating that each measured value after combination is larger than each measured value at the time of combination for all weighing hoppers, and data indicating that it is small And the data stored by the plurality of recent weighing error processings are the measured values after the combination for any first weighing hopper. If only the data indicating that the value is larger than the value, it is determined that the supply hopper disposed above the first weighing hopper is defective,
Data indicating that the data stored by a plurality of recent weighing error processes is only data indicating that each measured value after combination is larger than each measured value at the time of combination for all weighing hoppers, and data indicating that it is small And the data stored by the plurality of recent weighing error processings are the measured values after the combination for any second weighing hopper. If only the data indicating that the value is smaller than the value, it is determined that the second weighing hopper is defective,
Data indicating that the data stored by a plurality of recent weighing error processes is only data indicating that each measured value after combination is larger than each measured value at the time of combination for all weighing hoppers, and data indicating that it is small And the data stored by the plurality of recent weighing error processings are the measured values after the combination for the arbitrary third weighing hopper, A combination weighing device that determines that the weighing unit including the third weighing hopper and the corresponding weight detection means has a problem when both the data indicating the larger value and the data indicating the smaller value are included. . The control means outputs a first abnormality signal when determining that the balance stabilization waiting time is set to an inappropriate time, and the supply unit disposed above the first weighing hopper. If it is determined that the hopper is defective, a second abnormality signal is output. If it is determined that the second weighing hopper is defective, a third abnormality signal is output, and the third weighing signal is output. If it is determined that the weighing unit including the hopper and the weight detecting means corresponding thereto has a problem, a fourth abnormality signal is output,
The combination weighing apparatus according to claim 1, further comprising a notification unit that notifies that there is a defect corresponding to each of the first to fourth abnormality signals. The control means determines whether or not the total value is within the predetermined weight range, and when the total value is not within the predetermined weight range, discards the combination by the combination calculation and again The combination weighing device according to claim 1 or 2 , wherein the combination calculation is performed, and the combination by the combination calculation is not discarded when the combined value is a value within the predetermined weight range.

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