JP2005249457A - Combined weighing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a combined weighing apparatus, which can determine a target loading weight of a material to be weighed for a hopper, while reducing the operational burden of an operator. <P>SOLUTION: Each weighing hopper 7 weighs the loaded material to be weighed, and notifies a control part 8 of the weight. The control part 8 performs a combination calculation on the basis of the received weight of the material to be weighed, and selects the weighing hopper 7 for performing the discharge operation, on the basis of the result. The control part 8 calculates the target selection hopper number, to be the yardstick for the number of the weighing hoppers 7 to be selected on the basis of the result of the combination calculation, on the basis of loading condition information and participating hopper number information, and determines the target loading weight of the material to be weighed for the weighing hopper 7, using the obtained target selection hopper number. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a combination weighing device that performs combination calculation of the weights of a plurality of objects to be weighed.

  Patent Document 1 discloses a combination weighing device that measures an object to be weighed, such as confectionery and fruit, having variations in individual weights so as to have a total weight within an allowable range. In the combination weighing device described in Patent Document 1, a plurality of objects to be weighed are respectively loaded, and a plurality of weighing hoppers for holding and weighing the loaded objects to be weighed are provided. A weighing hopper is selected that combines the measured weights and discharges the objects to be weighed based on the result.

  The combination weighing device is also disclosed in Patent Documents 2 and 3.

Japanese Patent No. 3402687 JP 2002-206963 A Japanese Patent No. 3388832

  In the combination weighing device of Patent Document 1, information used only for determining the target input weight of an object to be weighed with respect to the weighing hopper, such as information called the number of selected hoppers and information called a pseudo combination target weight. Therefore, in order to operate the combination weighing device optimally, it is necessary to change the information on a trial and error basis.

  Accordingly, the present invention has been made in view of the above circumstances, and an object thereof is to provide a combination weighing device capable of determining a target input weight of an object to be weighed with respect to a hopper while reducing an operation burden on an operator. And

  In order to solve the above-mentioned problem, the invention of claim 1 is characterized in that a weighing object is respectively charged and a plurality of hoppers capable of discharging the charged weighing object and the hopper charged in the plurality of hoppers. A weighing unit for weighing each of the objects to be weighed, and a combination calculation of the weights of the objects to be weighed by the weighing unit, and based on a result of the combination calculation, discharge operation is performed among the plurality of hoppers. A hopper selection unit that selects a hopper to perform, a participation hopper number acquisition unit that acquires first information regarding the number of hoppers that participated in the combination calculation among the plurality of hoppers, and the weighing object for the plurality of hoppers Using a loading status acquisition unit that acquires second information related to the loading status, a calculation unit that calculates a target selection hopper number that serves as a guide for the number of selection hoppers in the hopper selection unit, and the target selection hopper number An input weight determining unit that determines a target input weight of the object to be weighed with respect to the plurality of hoppers, and the arithmetic unit calculates the number of the target selection hoppers based on the first and second information Device.

  The invention of claim 2 is the combination weighing device according to claim 1, further comprising a determination unit that determines whether or not a predetermined condition relating to the capability of the combination weighing device is satisfied, and the calculation unit includes: When the predetermined condition is satisfied in the determination unit, the target selection hopper number is obtained based on the first and second information.

  The invention according to claim 3 is the combination weighing device according to claim 2, wherein when the predetermined condition is satisfied in the determination unit, the hopper selected by the hopper selection unit is at least next time. It does not participate in the combination calculation in the weighing cycle.

  According to a fourth aspect of the present invention, there is provided a plurality of hoppers into which the objects to be weighed are respectively charged and capable of discharging the objects to be weighed, and the weights of the objects to be weighed into the plurality of hoppers. A weighing unit for weighing each of the hoppers, and a combination calculation of the weights of the objects to be weighed by the weighing unit, and a hopper for performing a discharge operation is selected from the plurality of hoppers based on the result of the combination calculation A hopper selection unit, a participation hopper number acquisition unit that acquires the number of hoppers that can participate in the combination calculation, a calculation unit that obtains a target selection hopper number that serves as a guide for the number of hoppers selected in the hopper selection unit, and An input weight determination unit that determines a target input weight of the objects to be weighed with respect to the plurality of hoppers using a target selection hopper number, and the calculation unit is half the number of hoppers that can participate in the combination calculation Seeking value, a combination weighing device the value of the half the value of the target selection hoppers number.

  Further, the invention of claim 5 is the combination weighing device according to claim 4, wherein the participation hopper number acquisition unit acquires first information regarding the number of hoppers participating in the combination calculation among the plurality of hoppers. And a loading status acquisition unit that acquires second information regarding the loading status of the objects to be weighed with respect to the plurality of hoppers, and a determination unit that determines whether or not a predetermined condition regarding the capability of the combination weighing device is satisfied. The calculation unit further determines the number of target selection hoppers based on the first and second information when the determination unit satisfies the predetermined condition, and the determination unit determines whether the predetermined condition is If not satisfied, a value half of the number of hoppers that can participate in the combination calculation is obtained, and the value of the half is set as the value of the target selection hopper number.

  Further, the invention of claim 6 is the combination weighing device according to claim 5, wherein when the predetermined condition is satisfied in the determination unit, the hopper selected by the hopper selection unit is at least next time. When the predetermined condition is not satisfied in the determination unit without participating in the combination calculation in the weighing cycle, the number of hoppers that can participate in the combination calculation in two consecutive weighing cycles is the same.

  A seventh aspect of the present invention is the combination weighing device according to any one of the first, second, fourth, and fifth aspects, wherein the object to be weighed is measured by the weighing unit. A weight stability determination unit that determines the stability of the weight of the object, wherein the hopper selection unit is based on a determination result of the weight stability determination unit, and is stable among weights of the objects measured by the measurement unit. The combination calculation is performed using only the weights that are used.

  The invention according to claim 8 is the combination weighing device according to any one of claims 1 and 5, wherein the first information is an average value of the number of hoppers participating in the combination calculation. The second information includes third information based on an average value and a standard deviation of the input weight of the objects to be weighed with respect to the plurality of hoppers, and the calculation unit includes the third information, The target selection hopper number is obtained using an arithmetic expression including a parameter to which an average value of the number of hoppers participating in the combination calculation is substituted.

  The invention of claim 9 is the combination weighing device according to claim 8, wherein the third information is an average value and a standard deviation of the input weight of the objects to be weighed in each of the plurality of hoppers. Is an average value among the plurality of hoppers.

  The invention according to claim 10 is the combination weighing device according to any one of claims 8 and 9, wherein the calculation formula is based on a probability that a target combination weight is obtained in the combination calculation. It is.

  According to the first aspect of the present invention, the target selection hopper number is obtained on the basis of the information on the input state of the objects to be weighed and the information on the number of hoppers participating in the combination calculation. Even when these pieces of information that may affect the change, the optimum target selection hopper number can be automatically obtained. Therefore, it is possible to determine the optimum target input weight of the object to be weighed while reducing the operation burden on the user.

  Further, according to the inventions of claim 2 and claim 5, since the method for obtaining the target selection hopper number is determined according to the capability of the combination weighing device, the optimum target selection hopper number according to the capability of the combination weighing device. Can be requested.

  Further, according to the invention of claim 3 and claim 6, regarding the method for obtaining the target selection hopper number, an appropriate method according to the content of the combination calculation processing is surely adopted, so that a more optimal weighing object can be obtained. A target input weight can be determined.

  According to the invention of claim 4, since the target selection hopper number is automatically obtained, the target input weight of the object to be weighed can be determined while reducing the operation burden on the user.

  According to the seventh aspect of the invention, since the combination calculation is performed using only the stable weight among the weights of the objects weighed by the weighing unit, an accurate combination calculation result can be obtained.

  Further, according to the inventions of claims 8 and 9, the number of target selection hoppers can be easily obtained using an arithmetic expression.

  Further, according to the invention of claim 10, since the arithmetic expression is based on the probability that the target combination weight is obtained, the target input weight of the object to be weighed is determined using the number of target selection hoppers obtained by the arithmetic expression. By doing so, it is possible to reliably improve the probability of obtaining the target combination weight.

Embodiment 1 FIG.
FIG. 1 is a diagram showing an overall configuration of a combination weighing device 1 according to Embodiment 1 of the present invention. 2 is a block diagram showing the configuration of the control unit 8 provided in the combination weighing device 1. FIGS. 3 and 4 show the configuration of the information acquisition unit 86 and the input weight determination unit 82 provided in the control unit 8, respectively. It is a block diagram.

  As shown in FIG. 1, the combination weighing device 1 includes a cross feeder 2, a dispersion feeder 3, and a plurality of heads 4. The combination weighing device 1 includes, for example, 14 heads 4, and these heads 4 are arranged in an annular shape when viewed from above. Each head 4 includes a radiation feeder 5, a pool hopper 6, and a weighing hopper 7. Further, the combination weighing device 1 includes a control unit 8, a RAM 9, a ROM 10, and a storage device 11 as a configuration for mainly controlling these components. Further, the combination weighing device 1 includes a display unit 12 that displays various information on the screen as an interface with the operator, and an operation unit 13 for inputting instructions from the operator.

  Although the operation unit 13 according to the first embodiment includes a keyboard and a mouse, the operation unit 13 may also be used as the display unit 12 such as a touch panel display. Although not shown, the combination weighing device 1 is also provided with a collective discharge chute into which the objects to be weighed discharged from the weighing hopper 7 are input.

  With such a configuration, the combination weighing device 1 according to the first embodiment is a device for combining and bagging objects to be weighed such as confectionery and fruits that have different individual weights so that the total weight is within an allowable range. Used. Needless to say, the present invention can also be used for a boxing device or a bottling device used for the same purpose.

  The cross feeder 2 includes a trough 20 on which an object to be weighed supplied to the combination weighing device 1 is placed, and a drive mechanism 21 that drives the trough 20 in a predetermined direction. The cross feeder 2 drives the trough 20 in a predetermined direction by the drive mechanism 21 so that the objects to be weighed (the objects to be weighed placed on the trough 20) supplied to the combination weighing device 1 are directed to the dispersion feeder 3. Transport. The drive mechanism 21 according to the first embodiment is driven based on an ON / OFF control signal from the control unit 8.

  The dispersion feeder 3 includes a dispersion table 30 on which an object to be weighed supplied from the cross feeder 2 is placed, and a base 31 that holds the dispersion table 30. The dispersion table 30 has a substantially conical upper surface, and the object to be weighed conveyed by the cross feeder 2 is supplied near the top of the upper surface as indicated by an arrow in FIG. The dispersion table 30 is held at a predetermined position by the base 31 and is driven to vibrate.

  By such vibration drive of the dispersion table 30, the object to be weighed conveyed and placed on the dispersion table 30 moves in the longitudinal direction while being dispersed in the circumferential direction on the upper surface, as indicated by arrows in FIG. It is conveyed to the radiation feeder 5 of each head 4. The vibration control of the dispersion feeder 3 is performed by the control unit 8.

  The plurality of radiating feeders 5 are arranged along the periphery of the circular edge of the dispersion table 30, and each includes a feeder unit 50 that receives and conveys an object to be weighed from the dispersion feeder 3 and a drive mechanism 51. . In each radiation feeder 5, the drive mechanism 51 drives the feeder unit 50 to vibrate with a predetermined amplitude for a predetermined time, thereby transporting an object to be weighed received by the feeder unit 50 in a predetermined direction and corresponding pool hopper. Carry to 6. The vibration intensity (vibration amplitude) and vibration time in the feeder unit 50 can be changed by the drive mechanism 51 based on a control signal from the control unit 8, and the vibration intensity and vibration time in the feeder unit 50 are adjusted. Thereby, the conveyance amount of the radiation feeder 5 can be controlled.

  Each pool hopper 6 is disposed below the tip of the corresponding radiating feeder 5 and temporarily holds an object to be weighed supplied from the radiating feeder 5. Each pool hopper 6 inputs an object to be weighed held in the corresponding weighing hopper 7 by opening an open / close gate (not shown) at a predetermined timing based on a control signal from the control unit 8. .

  Each weighing hopper 7 is arranged directly below the corresponding pool hopper 6 and holds an object to be weighed supplied from the pool hopper 6. Each weighing hopper 7 is provided with a load cell (not shown). The load cell measures the weight of the object to be weighed held by the weighing hopper 7 and outputs the measurement result to the control unit 8 as a weighing signal. To do. Further, each weighing hopper 7 performs a discharging operation by opening an open / close gate (not shown) based on a control signal from the control unit 8, and throws the held objects to the collective discharge chute.

  In this way, the plurality of weighing hoppers 7 are loaded with the objects to be weighed in a plurality, and function as a hopper capable of discharging the loaded objects to be weighed, while the objects loaded into the hoppers are functioning as hoppers. Functions as a measuring unit that measures the weight of the object.

  The collective discharge chute collects the objects to be weighed discharged from the weighing hopper 7 selected by the combination calculation described later in one place and discharges them downward. Then, the objects to be weighed discharged from the collective discharge chute are supplied to the subsequent packaging device or the like.

  As can be understood from the above description, in the combination weighing device 1, the weighing hoppers 7 and the radiation feeders 5 are associated with each other in a one-to-one correspondence. The control unit 8 can determine which radiation feeder 5 is the object to be weighed.

  In the combination weighing device 1 according to the first embodiment, the dispersion direction of the objects to be weighed is the direction in which the objects to be weighed are transported from the dispersion feeder 3 to the weighing hopper 7, and the “dispersion direction of the objects to be weighed” The “distribution state between” refers to the variation of the objects to be weighed in the direction perpendicular to the dispersion direction, and affects the difference in the input weight of the objects to be weighed at a certain moment in the plurality of weighing hoppers 7.

  The control unit 8 includes a CPU, a DSP (digital signal processor), and the like, and is connected to other components of the combination weighing device 1 via an interface circuit and bus wiring (not shown). The control unit 8 reads the program stored in the ROM 10 onto the RAM 9 and controls other components of the combination weighing device 1 by performing a predetermined calculation according to the program.

  The storage device 11 is a device for storing various data and corresponds to a readable / writable hard disk device or the like, but a portable recording medium (CD-ROM) such as a CD-ROM reader or a card reader. A device using a ROM or a memory card may be used.

  Next, the configuration of the control unit 8 will be described in detail with reference to FIGS. As shown in FIG. 2, the control unit 8 includes a hopper selection unit 80, a situation determination unit 81, an input weight determination unit 82, a parameter setting unit 83, a weighing signal processing unit 84, an operation mode determination unit 85, and an information acquisition unit 86. The calculation unit 87 and the radiation feeder control unit 88 are provided, and these components are functional elements realized by the control unit 8 operating according to the above-described program.

  The weighing signal processing unit 84 amplifies the analog weighing signal output from each weighing hopper 7 and converts it into a digital signal. Then, the weighing signal processing unit 84 filters the weighing signal converted into a digital signal, generates the weighing data 100 indicating the filtered weighing signal, and stores it in the RAM 9. Accordingly, the weighing data 100 indicates the weight of the object to be weighed that is put in each weighing hopper 7.

  Here, when an object to be weighed is introduced from the pool hopper 6 to the weighing hopper 5, mechanical vibration is applied to the weighing hopper 5, so that the weight of the object to be weighed immediately stabilizes even if filtering is performed. In addition, a certain amount of time is required until the measurement signal output from the signal vibrates and stabilizes. In the measurement signal processing unit 84 according to the first embodiment, a combination calculation described later is executed a predetermined number of times per minute regardless of whether the measurement signal is stable. Therefore, the weighing data 100 may include data indicating an unstable weighing signal, and an accurate calculation result cannot be obtained when a combination calculation is performed using such an unstable weighing signal. .

  Therefore, the measurement signal processing unit 84 according to the first embodiment determines whether or not the measurement signal is stable immediately after filtering, and stores the data indicating the determination result in the RAM 9 including the measurement data 100. Yes. Then, by referring to this determination result at the time of combination calculation, use of an unstable measurement signal is avoided. In this way, the weighing signal processing unit 84 also functions as a weight stability determination unit that determines the stability of the weight of the object weighed by each weighing hopper 7.

  The determination as to whether or not the weighing signal is stable can be made, for example, by sampling the weighing signal a plurality of times and confirming whether or not the sampling values are all the same.

  The hopper selection unit 80 performs combination calculation of the weights of the objects to be weighed based on the weighing data 100 in the RAM 9. Specifically, the weight data 100 indicates a combination of weights to be a target total weight among the weights of the objects to be weighed in the plurality of weighing hoppers 7, or within a preset allowable range if it does not exist. The combination of weights closest to the target total weight is obtained. The hopper selection unit 80 selects each weighing hopper 7 that holds the objects to be weighed constituting the obtained combination from the weighing hoppers 7, and causes the selected weighing hopper 7 to open the open / close gate. Output a control signal. For example, the target total weight is set as the lower limit of the allowable range.

As a result, a hopper that performs a discharging operation among the plurality of weighing hoppers 7 is selected based on the result of the combination calculation, and the objects to be weighed in the selected weighing hoppers 7 are discharged to the collective discharge chute. As a result, an object to be weighed showing a weight within a predetermined allowable range is sent to a packaging device or the like. Hereinafter, the total weight of the objects to be weighed discharged from the respective weighing hoppers 7 selected based on the result of the combination calculation is referred to as “combination weight Wc”, and the above-mentioned target total weight, which is the target weight, is referred to as “target combination weight W _ct. "

Further, the hopper selection unit 80 generates history data 101 indicating the result of the combination calculation and writes it in the RAM 9. The history data 101 includes data indicating the weight of an object actually put into the weighing hopper 7 for each weighing cycle (hereinafter referred to as “loading weight W _t ”), and the number of participating hoppers N for each weighing cycle. and data indicating _p .

Here, the “number of participating hoppers N _p ” means the number of weighing hoppers 7 that actually participate in one combination calculation among the weighing hoppers 7 mounted on the combination weighing device 1. In other words, it means the number of weighing hoppers 7 holding the objects to be weighed indicating the respective weights actually used in one combination calculation. In the present combination weighing device 1, the number of weighing hoppers 7 participating in one combination calculation is smaller than the total number N _total of the weighing hoppers 7, and the number may change. The cause will be described below.

First, as a first cause, in the combination weighing device 1, the maximum number of weighing hoppers 7 that can participate in the combination calculation (hereinafter referred to as “the maximum number of hoppers N _cmax that can be participated” due to the limitation of the calculation capability of the control unit 8. ), In other words, the maximum number of weighing hoppers 7 that can be selected by the hopper selection unit 80 is limited to, for example, 10. Due to this limitation, the weighing hopper 7 can be configured as in the first embodiment. Even if the total number N _total is larger than 10, only 10 weighing hoppers 7 can participate in the combination calculation, and the hopper selection unit 80 can select only 10 weighing hoppers 7 at maximum. For this reason, in the first embodiment, the number of weighing hoppers 7 participating in one combination calculation is less than the total number N _{total of} the weighing hoppers 7. Unlike the first embodiment, the weighing hoppers 7 of If the number N _total is less than 10, since the total number N _total maximum participation possible hoppers number N Weighing than _cmax hopper 7 is small, such restriction as to the number of the weighing hoppers 7 to participate in the combination calculation No.

  Next, as a second cause, there is an operation mode of the combination weighing device 1. In the present combination weighing device 1, the operation mode includes the double shift mode in which the weighing hopper 7 selected by the hopper selection unit 80 cannot participate in the combination calculation in the next weighing cycle, and the weighing hopper 7 selected by the hopper selection unit 80. A triple shift mode that cannot participate in the combination calculation in the next and subsequent weighing cycles, and a single shift mode in which even the weighing hopper 7 selected by the hopper selection unit 80 may participate in the combination calculation in the next weighing cycle. The second cause is the operation in the double shift mode and the triple shift mode.

For example, in the double shift mode in which the _total number N _total of the weighing hoppers 7 is 14 as in the first embodiment, if the hopper selection unit 80 selects five weighing hoppers 7 in a certain weighing cycle, the next time In the combination calculation in the weighing cycle, only 9 (= 14−5) weighing hoppers 7 can participate. Accordingly, the hopper selection unit 80 performs combination calculation using the weights of the objects to be weighed from the nine weighing hoppers 7. In the present example, as described above, the maximum number of hoppers N _cmax that can be participated is limited to 10. Therefore, when only three weighing hoppers 7 are selected in a certain weighing cycle, the next weighing cycle is used. In the combination calculation, only 10 weighing hoppers 7 can participate, not 11 (= 14-3).

Thus, even when the combination weighing device 1 operates in the double shift mode or the triple shift mode, the number of weighing hoppers 7 participating in one combination calculation is larger than the total number N _total of the weighing hoppers 7. Depending on the number of weighing hoppers 7 to be selected, the number of weighing hoppers 7 that can participate in the next combination calculation may change. The reason why the double shift mode or triple shift mode is selected will be described later. In addition, operation modes other than the single shift mode such as the double shift mode and the triple shift mode may be simply referred to as “other operation modes” hereinafter.

Due to the first and second causes as described above, the number of weighing hoppers 7 that actually participate in the combination calculation may change. As a result, the number of participating hoppers N _p included in the history data 101 is indicated. Data can also change.

  The operation mode determination unit 85 determines whether the combination weighing device 1 operates in the single shift mode or other operation modes, generates operation mode data 105 indicating the determination result, and writes the operation mode data 105 in the RAM 9.

As shown in FIG. 3, the information acquisition unit 86 includes a participation hopper number acquisition unit 860, a participation hopper number acquisition unit 861, a loading status acquisition unit 862, and a feeder setting acquisition unit 863, and includes head data 106. Is written into the RAM 9. The head data 106 can participate in participation hopper number data 107 indicating information related to the participation hopper number N _p (hereinafter referred to as “participation hopper number information”) and one combination operation in the single shift mode. Participable hopper number data 108 indicating information relating to the number of hoppers (hereinafter referred to as “participable hopper number N _c ”) and information relating to the input state of an object to be weighed into the weighing hopper 7 (hereinafter referred to as “input state information”). ) And feeder setting data 110 indicating information related to the setting of the driving amplitude and driving time of the radiation feeder 5 (hereinafter referred to as “radiation feeder setting information”).

When the operation mode data 105 indicates the single shift mode, the participation hopper number acquisition unit 860 generates the participation hopper number data 108 based on the hopper number initial data 112 input by the operator via the operation unit 13, and the RAM 9 Write to. Here, the “initial hopper number data” includes data indicating the maximum participation hopper number N _cmax and data indicating the total number N _total of the weighing hoppers 7.

Participatable hopper number obtaining unit 860, when the total number N _total weighing hoppers 7 is greater than the maximum participation possible hoppers number N _cmax is the maximum participatable hopper number N _cmax and participable hopper number N _c, weighing hoppers 7 When the total number N _total is equal to or less than the maximum participation hopper number N _cmax , the participation hopper number data 108 is generated with the _total number N _total of the weighing hoppers 7 as the participation hopper number N _c .

Join hopper number obtaining unit 861, if the operation mode data 105 showing the other operation mode, write to RAM9 generates a join hoppers number data 107 based on the data indicating the participation hoppers number N _p included in the history data 101 . Charged state acquisition section 862 generates a charged status data 109 in accordance with the data indicating the charged weight W _t included in the history data 101, and writes the RAM 9. The feeder setting acquisition unit 863 generates feeder setting data 110 based on parameter data 104 described later and writes it in the RAM 9.

The calculation unit 87 is based on the participation hopper number data 108 when the operation mode data 105 indicates the single shift mode, and based on the participation hopper number data 107 and the throwing state data 109 when other operation modes are indicated. It generates a target selected hoppers number data 111 showing the target selected hoppers number N _st and write to RAM 9. Here, the “number of target selection hoppers N _st ” is a measure of the number of weighing hoppers 7 selected by the hopper selection unit 80 (hereinafter referred to as “number of selected hoppers N _s ”), which will be described later. Thus, the calculation is performed based on the probability that the target combination weight _Wct is obtained in the combination calculation.

  The status determination unit 81 determines the distribution status of the objects to be weighed dispersed by the dispersion feeder 3 based on the loading status data 109 and the feeder setting data 110 acquired by the information acquisition unit 86, and shows the determination result. Determination data 102 is generated and written to the RAM 9.

As shown in FIG. 4, the input weight determination unit 82 includes a maximum correction value acquisition unit 820, a correction value acquisition unit 821, and a target value calculation unit 822, and a plurality of values are determined according to the determination data 102. A target value (hereinafter referred to as “target input weight W _tt ”) of the input weight of the object to be weighed to each of the weighing hoppers 7 is assigned, and a target indicating each measurement hopper 7 and the target input weight W _tt assigned to each of the weighing hoppers 7. The input weight data 103 is generated and written in the RAM 9. The input weight determining unit 82 also determines the target input weight _Wtt using the target selection hopper number _Nst .

  The parameter setting unit 83 controls the conveyance force of each radiation feeder 5 for conveying an object to be weighed to each weighing hopper 7 in accordance with the target input weight data 103 (hereinafter referred to as “conveying force parameter”). Is calculated, and parameter data 104 indicating the conveyance force parameter is generated and written in the RAM 9. The conveyance force parameter is composed of an amplitude parameter A related to the vibration amplitude in each radiation feeder 5 and a time parameter T related to the driving time. When the parameter setting unit 83 generates the parameter data 104, the parameter setting unit 83 newly writes the parameter data 104 in the RAM 9 without deleting the old parameter data 104. Accordingly, the past parameter data 104 is stored together with the latest parameter data 104 in the RAM 9.

  The radiation feeder control unit 88 controls the operation of the drive mechanism 51 in the radiation feeder 5 based on the parameter data 104 in the RAM 9, and thereby the feeder unit 50 vibrates.

  Thus, in the present combination weighing device 1, it is possible to control the drive amplitude and drive time of each radiation feeder 5 using the amplitude parameter A and the time parameter T, thereby conveying the radiation feeder 5. Force can be controlled easily. Although not shown, the control unit 8 is also provided with functional blocks for controlling the operation of the cross feeder 2 and the distributed feeder 3.

Initial setting information is input to the combination weighing device 1 by operating the operation unit 13 by an operator. The input initial setting information is notified to the control unit 8, and the control unit 8 generates initial setting data indicating the received initial setting information and writes it into the storage device 11. The initial setting data includes data indicating the target combined weight _Wct , initial values of the target input weight data 103 for each weighing hopper 7, initial values of the parameter data 104 for controlling the radiation feeder 5, and the hopper number initial values described above. Data 112, capability data indicating information on the capability of the combination weighing device 1, and the like are included. The capability data will be described later in detail.

  In the present combination weighing device 1 configured as described above, an object to be weighed is put into each weighing hopper 7 via the cross feeder 2, the dispersion feeder 3, the radiation feeder 5 and the pool hopper 6. Then, the combination calculation is executed, and the weighing hopper 7 that performs the discharging operation is selected based on the result. The selected weighing hopper 7 discharges the objects to be weighed to the collective discharge chute, and the objects to be weighed are again put into the weighing hopper 7 which has become empty. Then, the combination calculation is executed again, and thereafter the same operation is repeatedly executed. Note that one weighing cycle is completed when the object to be weighed is discharged from the weighing hopper 7, and after the object to be weighed is discharged by the weighing hopper 7, the next weighing cycle is started.

Next, the combination calculation performed by the hopper selection unit 80 will be described in detail. FIG. 5 is a flowchart showing the combination calculation process. As shown in FIG. 5, in step s1, the hopper selection unit 80 stabilizes the weighing signal based on the data included in the weighing data 100 and indicating the determination result of whether or not the weighing signal is stable. The weighing hopper 7 is recognized and the number (hereinafter referred to as “stable hopper number N _ss ”) is acquired.

  In step s2, it is determined whether the following conditional expression (1) is satisfied.

When the conditional expression (1) is satisfied in step s2, in step s3, the hopper selection unit 80 selects the same number of weighings as the maximum possible participation hopper number N _cmax from the weighing hoppers 7 in which the weighing signal is stable. Select hopper 7.

Here, numbers 1 to N (N = N _total ) are assigned to the heads 4 of the combination weighing device 1, and the radiation feeder 5, the pool hopper 6, and the weighing hopper 7 also have the heads 4 to which they belong. The same number as the number is assigned. The hopper selection unit 80 counts the number of times each weighing hopper 7 participates in the combination calculation, and writes the information together with the number of the weighing hopper 7 in the history data 101 and writes it in the RAM 9. The number of times of participation in the combination calculation for each weighing hopper 7 is reset when the corresponding weighing hopper 7 performs the discharge operation of the object to be weighed. In step s3, the weighing hopper 7 is selected in the descending order of the number of times of participation in the past combination calculation with reference to the history data 101, that is, in the descending order of the number of stays of the object to be weighed.

  When step s3 is executed, in step s4, the hopper selection unit 80 causes the selected weighing hopper 7 to participate in the combination calculation. That is, the combination calculation is performed using the weight of the weighing object from the selected weighing hopper 7.

  On the other hand, if the conditional expression (1) is not satisfied in step s2, in step s5, the hopper selection unit 80 causes all the weighing hoppers 7 whose weighing signals are stable to participate in the combination calculation.

As described above, in the first embodiment, only the stable weight among the weights weighed by the weighing hoppers 7 is used to perform the combination calculation. Therefore, an accurate combination calculation result can be obtained. Further, when all the weighing signals output from the respective weighing hoppers 7 are stable, in the combination weighing device 1 according to the first embodiment, the stable hopper number N _ss > the maximum participation hopper number N _cmax is always satisfied. Therefore, the number of weighing hoppers 7 selected in step s3 is 10. Accordingly, the number of hoppers _Nc that can participate in two consecutive weighing cycles coincide with each other.

  The hopper selection unit 80 according to the first embodiment causes the weighing hopper 7 in which the weighing signal is actually stable to participate in the combination calculation, so that the weighing signal is not stable in the weighing cycle in which the weighing signal is output. In some cases, the weighing hopper 7 participating in the combination calculation in a certain weighing cycle cannot participate in the next weighing cycle. Such an operation mode is the above-described double shift mode. If the weighing signal output from the weighing hopper 7 is not stable not only in the weighing cycle but also in the next weighing cycle, the weighing hopper 7 that has participated in the combination calculation in a certain weighing cycle can perform the next and subsequent weighing cycles. It may happen that you cannot participate. Such an operation mode is the above-described triple shift mode. All the weighing signals output from the respective weighing hoppers 7 are stable, and an operation mode in which the number of weighing hoppers 7 that can participate in the combination calculation in two consecutive weighing cycles is the single shift mode.

  As described above, in the first embodiment, in each weighing cycle, the weighing hopper 7 in which the weighing signal is actually stable participates in the combination calculation, so that the operation mode results in the single shift mode or the double shift mode. Or triple shift mode.

  Next, in the present combination weighing device 1, a series of operations from the start of operation to the adjustment of the operation conditions of the radiation feeder 5 will be described in detail. FIG. 6 is a flowchart showing such a series of operations.

  First, in the combination weighing device 1, when the operation starts, initial setting is executed (not shown). In the initial setting, the control unit 8 reads the above-described initial setting data from the storage device 11 and writes it in the RAM 9.

  When the initial setting is completed, as shown in FIG. 6, in step s11, the conveyance of the object to be weighed is started, and the control unit 8 controls the cross feeder 2, the dispersion feeder 3, the radiation feeder 5 and the pool hopper 6. Thus, an object to be weighed is put into each weighing hopper 7.

  The weighing hopper 7 measures the weight of the object to be weighed and sends a weighing signal indicating the result to the weighing signal processing unit 84 of the control unit 8. Then, the measurement signal processing unit 84 sequentially performs amplification processing, digital conversion processing, and filtering processing on the received measurement signal, generates the measurement data 100, and writes it into the RAM 9.

Next, the combination weighing process is executed in step s12. In the combination weighing process, first, an operation mode determination process is performed. In this operation mode determination process, the operation mode determination unit 85 of the control unit 8 determines the operation mode of the combination weighing device 1 based on the capability data included in the initial setting data in the RAM 9. The capability data includes the number of combination operations N _a (for example, N _a = 120 times / second) performed by the combination weighing device 1 per second, the hopper delay time t _d , the hopper stabilization time t _s , the filter time t _f , and the combination Data indicating the calculation time t _c is included.

Here, the “hopper delay time t _d ” means that the weighing object is discharged from the weighing hopper 7 from the start of the opening operation of the opening / closing gate of the weighing hopper 7 when the selected weighing hopper 7 discharges the weighing object. This means the time until the opening operation of the open / close gate of the pool hopper 6 starts when the pool hopper 6 puts an object to be weighed into the empty weighing hopper 7. The “hopper stabilization time t _s ” means that the object to be weighed is introduced into the weighing hopper 7 from the start of the opening operation of the open / close gate of the pool hopper when the pool hopper 6 introduces the object into the weighing hopper 7. This means the time until the weighing signal output from the weighing hopper 7 into which the object to be weighed is stabilized. The “filter time t _f ” means a time required for filtering the measurement signal in the measurement signal processing unit 84, and the “combination calculation time t _c ” means a combination calculation performed by the hopper selection unit 80. Means the time needed to.

FIG. 7 is a flowchart showing the operation mode determination process. As shown in FIG. In step s21, the operation mode determination section 85 obtains the time t _z represented by the following equation (2).

The operation mode determination unit 85, in step s22, determining the time t _y of the following formula (3).

Note in Figure 8, the hopper delay time t _d, hopper stabilization time t _s, the filter time t _f, the combination calculation time t _c, and time t _y, previously shows the relationship between t _z.

  Next, the operation mode determination part 85 determines whether the following conditional expression (4) regarding the capability of the combination weighing | measuring device 1 is satisfied in step s23. That is, the operation mode determination unit 85 functions as a determination unit that determines whether or not the conditional expression (4) is satisfied.

  When the conditional expression (4) is satisfied, the operation mode determination unit 85 determines in step s25 that the operation mode of the combination weighing device 1 is another operation mode, and the operation mode data 105 indicating the operation mode. Is written into the RAM 9. On the other hand, when the conditional expression (4) is not satisfied, the operation mode determination unit 85 determines in step s24 that the operation mode of the combination weighing device 1 is the single shift mode, and the operation mode data 105 indicating this. Is written into the RAM 9.

As can be understood from FIG. 8 and equation (3), when the time _ty is focused on one weighing hopper 7, the object to be weighed is discharged from the start of the opening / closing gate opening, and a new object is This indicates the time required for the weighing object to be input, the weighing signal to be output, the weighing signal to be stabilized, and the filtering to be completed, and the pool hopper 6, the weighing hopper 7 and the control unit of the combination weighing device 1. It can be said that it shows 8 abilities.

Moreover, as can be understood from FIG. 8 and equation (2), the time t _z from the opening operation starting of the opening and closing gates of the weighing hoppers 7 selected based on the results of one combination calculation, to start the next combination calculation It can be said that it shows the capability of the present combination weighing device 1 as a whole.

Accordingly, as shown in FIG. 8, if from the time t _y is greater time t _z is a timing to execute N _a of times the combination computation per minute, combination calculation by performing filtering for the weighing signal Is started, an unstable measurement signal is used in the combination calculation, and an accurate calculation result cannot be obtained. Therefore, in such a case, it is estimated that the combination weighing device 1 will operate in the double shift mode or the triple shift mode, and the operation mode data 105 indicating other operation modes is generated as the operation mode determination result. doing.

On the other hand, when the time _ty is equal to or less than the time _tz , when the combination calculation is started by performing filtering on the measurement signal at the above timing, an unstable measurement signal is not used in the combination calculation. In such a case, it is estimated that the combination weighing device 1 will operate in the single shift mode, and the operation mode data 105 indicating the single shift mode is generated.

Since the time t _y indicated performance data is the worst value of the design may be different than the value of the middle of the combination weighing device 1 is actually running. Therefore, although the operation mode data 105 indicates other operation modes, the actual operation mode may be the single shift mode, and the operation mode determined by the operation mode determination unit 85 is the actual operation mode. And may be different.

  When the operation mode is determined as described above, in the combination weighing process, the hopper selection unit 80 performs combination calculation using the weighing data 100 and selects the weighing hopper 7 based on the result.

Weighing hoppers 7 is selected, the control of the hopper selector 80 performs the operation of discharging the objects to be weighed at a predetermined timing, by which, the objects to be weighed indicating the target combination weight W _ct, or the target combination weight W _ct Items to be weighed that are close in weight are packaged. At this time, the history data 101 is generated by the hopper selection unit 80 and stored in the RAM 9.

  Next, in step s13, the control unit 8 increments a measurement number counter (not shown in FIG. 1) provided in the combination weighing device 1 every time one combination weighing process (step s12) is completed. . The weighing number counter is a counter that counts the number of times the combination weighing process is executed, in other words, the number of weighing cycles.

  Next, in step s14, the control unit 8 determines whether or not the value of the measurement number counter has reached the predetermined value C, and if not, the execution of steps s15 to s18 described later is skipped. Continue processing. In the combination weighing device 1 according to the first embodiment, the predetermined value C in step s14 is set to 100 times, but the present invention is not limited to this.

  On the other hand, when the value of the measurement number counter reaches 100 times in step s14, the combination weighing device 1 executes steps s15 to s18. That is, in step s14, in combination weighing device 1, steps s15 to s18 are executed once every time combination weighing processing (step s12) is performed 100 times.

  In step s15, a sampling process is executed. In the sampling process, the control unit 8 samples past data from the history data 101 and performs an operation based on the sampled data. This will be specifically described below.

The charging state acquisition unit 862 in the information acquisition unit 86 of the control unit 8 acquires the past measurement result of each weighing hopper 7 from the history data 101, and the standard deviation σ of the input weight W _t during the C measurement operations. _n (n = 1 to N) and average value X _n (hereinafter referred to as “average input weight X _n ”) are calculated for each weighing hopper 7. Then, information based on the average input weight X _n and the standard deviation σ _n is obtained. Specifically, an average value σ _t of standard deviations σ _n of all weighing hoppers 7 and an average value X _t of average input weights X _n of all weighing hoppers 7 are obtained. The loading status acquisition unit 862 generates loading status data 109 using the average loading weight X _n and standard deviation σ _n for all the weighing hoppers 7 and the average values X _t and σ _{t as} information based on the average loading weight X _n. Then, the data is written into the RAM 9.

Note that the symbol n at the end of the sign in the standard deviation σ _n and the average input weight X _n indicates the number of the head 4 corresponding to those values. For example, the average input weight X ₁ and the standard deviation σ ₁ are the average input weight and standard deviation in the weighing hopper 7 belonging to the first head 4. Thereafter, the same applies to the symbol n at the end of the code.

Further, the sampling process in step s15, the feeder setting acquisition unit 863 reads the parameter data 104 from within RAM 9, to obtain the past amplitude parameter A _n of each radiating feeder 5. Then, the average value RFA _n (hereinafter, referred to as "average amplitude parameter RFA _n") of the amplitude parameter A _n for each radiation feeder 5 with obtaining the further average value RFA _t of the average amplitude parameter RFA _n of total radiation feeders 5 Ask. Further, the feeder setting acquisition unit 863 acquires the past time parameter T _n for each radiation feeder 5 in the same manner, the average value RFT _n (hereinafter the time parameter T _n for each radiation feeder 5, the "average time parameter RFT _n And an average value RFT _t of the average time parameter RFT _n of all the radiation feeders 5 is obtained.

The feeder setting acquisition unit 863 generates feeder setting data 110 using the average amplitude parameter RFA _n and average time parameter RFT _n and average values RFA _t and RFT _t for each radiation feeder 5 as radiation feeder setting information, and stores them in the RAM 9. Write.

Further, in the sampling process, when the operation mode data 105 indicates another operation mode, the participation hopper number acquisition unit 861 acquires the past participation hopper number N _p from the history data 101, and participates while performing the weighing operation C times. The average value N _pp of the hopper number N _p is obtained, and the participation hopper number data 107 is generated and written in the RAM 9 as the participation hopper number information.

When the sampling process ends, in step s16, the combination weighing device 1 executes a target input weight setting process. FIG. 9 is a flowchart showing details of the target input weight setting process executed by the combination weighing device 1. First, in step s31, a target selection hopper number calculation process is performed. FIG. 10 is a flowchart showing details of this processing. As shown in FIG. 10, in the target selection hopper number calculation process, the calculation unit 87 recognizes the operation mode indicated by the operation mode data 105 in step s41. When the operation mode data 105 indicates the single shift mode, in step s42, the calculation unit 87 acquires the participation hopper number _Nc from the participation hopper number data 108. In step s43, the calculation unit 87 obtains a value that is half of the number of possible hoppers _Nc , and sets this half value as the target selected hopper number _Nst .

As described above, when the operation mode data 105 indicates the single shift mode, the half of the number of possible hoppers _Nc is set as the target selection hopper number _Nst, and each weighing hopper 7 uses the target selection hopper number _Nst . By determining the target input weight W _tt , the probability of obtaining the target combination weight W _ct is improved. This reason will be described later in detail.

On the other hand, when the operation mode data 105 indicates another operation mode in step s41, the calculation unit 87 calculates the average values X _t and σ _t from the loading status data 109 and the average value from the participating hopper number data 107 in step s44. Get N _pp . The arithmetic unit 87, in step s45, determine a target selected hoppers number N _st using the acquired following expression with these values (5).

As is clear from the above, the arithmetic expression (5) is obtained by calculating the average value N _pp of the participating hopper numbers N _p and the average values X _t and σ _t that are information based on the average input weight X _n and the standard deviation σ _n. This is an arithmetic expression including a parameter to be substituted. Then, as will be described later, the calculation formula (5) is calculated based on the probability that the target combination weight _Wct is obtained in the combination calculation. Therefore, the target combination weight W _tt is calculated by calculating the target selection hopper number N _st using the calculation formula (5) and determining the target input weight W _tt of the object to be weighed using the target selection hopper number N _{st. The} probability of obtaining _ct can be improved without fail. The method for obtaining the calculation formula (5) will be described later in detail.

When the target selection hopper number calculation process is completed, in step s32 of FIG. 9, the situation determination unit 81 uses the insertion situation data 109 and the feeder setting data 110 to calculate the index α _n for each weighing hopper 7 according to the following equation (6). Ask for.

Here, (X _n / X _t ) indicates the ratio of the input weight W _t of the nth weighing hopper 7 to the total weighing hopper 7, and the weighing hopper 7 into which a relatively large amount of objects to be weighed is charged. The larger the value. Therefore, the index α _n is a numerical value indicating the variation between the weighing hoppers 7 of the objects to be weighed put into the weighing hopper 7.

In the combination weighing device 1, even if the input weight W _t of the weighing hopper 7 is simply compared, it is determined whether the result is due to the distribution state of the objects to be weighed in the dispersion direction or due to the conveying force of the radiation feeder 5. Can not do it.

Here, (RFA _t / RFA _n ) × (RFT _t / RFT _n ) in the equation (6) represents the reciprocal of the ratio of the conveying force of the nth radiating feeder 5 to the total radiating feeder 5, The value becomes larger as the weighing hopper 7 to which an object to be weighed is conveyed by the radiation feeder 5 having a smaller conveying force.

Therefore, the index α _n has a larger value as the weighing hopper 7 to which a large number of objects to be weighed is conveyed, although the conveying force is small for each weighing hopper 7. In other words, the index α _n is an index indicating a variation state between the weighing hoppers 7 of the objects to be weighed conveyed to all the weighing hoppers 7, and indicates a distribution state of the objects to be weighed dispersed by the dispersion feeder 3 in the dispersion direction. It is an indicator to show.

When the index α _n is obtained for each weighing hopper 7, the situation determination unit 81 calculates the index β in step s33. The situation determination part 81 calculates | requires parameter | index (beta) by the following formula | equation (7).

The index β is a large value when the input weight W _t for all the weighing hoppers 7 is small and the standard deviation is large. In other words, the index β is an index indicating the variation status of the weighing objects conveyed to all the weighing hoppers 7 for each weighing cycle. When the indexes α _n and β are obtained, the situation determination unit 81 generates determination data 102 indicating the indexes α _n and β and writes the determination data 102 in the RAM 9.

When the determination of the distribution status of the objects to be weighed by the status determination unit 81 is completed, the input weight determination unit 82 starts a process for _obtaining the target input weight W _tt of each weighing hopper 7. Here, since the target input weight W _{tt according to the} first embodiment is set for each weighing hopper 7, it is rewritten as “target input weight W _ttn ”.

  First, in step s34, the maximum correction value acquisition unit 820 of the input weight determination unit 82 calculates the maximum correction value SMax based on the index β indicated in the determination data 102.

In this combination weighing device 1, in principle, the target input weight W _ttn between the weighing hoppers 7 is intentionally _varied . The maximum correction value SMax indicates the degree of variation, and is a correction value for _{obtaining the} maximum target input weight W _ttn with respect to the reference target input weight W _ref expressed by the following equation (8). That is, when the maximum correction value SMax is large, the difference between the set target input weights W _ttn for each weighing hopper 7 increases, and when the maximum correction value SMax is the minimum value “0”, all The target input weight W _ttn of the weighing hopper 7 becomes the same value.

Here, if the target input weight W _ttn is the same among the weighing hoppers 7, the input weight W _t is set to the target input in all the weighing hoppers 7 when an excessive object is supplied to each weighing hopper 7. The weight W _ttn may be exceeded, and it may occur that there is no combination of weights for which the target combination weight W _ct is obtained in the combination calculation. In the first embodiment, in order to prevent this, in principle, the target input weight W _ttn varies between the weighing hoppers 7.

In the first embodiment, when the index β satisfies β <0.2 and the variation in the input weight W _t is relatively small, the maximum correction value SMax is obtained by the following equation (9).

  When the index β satisfies 0.2 ≦ β ≦ 0.5, the maximum correction value SMax is obtained by the following equation (10).

When the index β satisfies 0.5 <β and the variation in the transported weight is relatively large, the maximum correction value SMax is obtained by the following equation (11).

As described above, the maximum correction value acquisition unit 820 of the combination weighing device 1 is a variation result (index) for each weighing operation (weighing cycle) of the object to be weighed conveyed to the weighing hopper 7, which is a determination result of the situation determination unit 81. The maximum correction value SMax is calculated and obtained according to β).

FIG. 11 is a diagram illustrating a relationship between the index β and the maximum correction value SMax. In the combination weighing device 1, the case where the value of the index β is small is a case where the weight of the object to be weighed is relatively stable for each weighing cycle when attention is paid to a certain weighing hopper 7. is there. In such a case, the error between the target input weight W _ttn set for the weighing hopper 7 and the weight of the actually measured object to be weighed becomes small. On the other hand, when the value of the index β is large, an error between the target input weight W _ttn set for the weighing hopper 7 and the weight of the actually transported object is relatively large.

As is apparent from FIG. 11, in the present combination weighing device 1, the maximum correction value SMax is set to a relatively large value when the index β is small, and the difference between the target input weights W _ttn allocated to the respective weighing hoppers 7 is determined. Enlarge. Thereby, in each weighing cycle, intentional variation can be given to the weight of the object actually transported to the weighing hopper 7, and an efficient combination calculation can be performed.

On the other hand, when the index β is large, the maximum correction value SMax is set to be relatively small, and the difference between the target input weights W _ttn assigned to the respective weighing hoppers 7 is reduced. This is because, when the input weight W _t at the weighing hopper 7 has a large variation for each weighing cycle, a difference is provided in each target input weight W _ttn to further increase the weight of the object to be transported. This is because there is no need to give variation. Thus, in each weighing cycle, the variation in between the weighing hoppers 7 Turning-on weight W _t in each of the weighing hoppers 7 can be suppressed to an appropriate state, it is possible to perform efficient combination calculation.

As described above, in the combination weighing device 1 according to the first embodiment, during weighing operation, the weighing objects are assigned to the weighing hoppers 7 according to the variation status of the weighing objects put into all the weighing hoppers 7 for each weighing cycle. The target input weight W _ttn to be changed can be changed. Therefore, since the weighing operation according to the operation state of the combination weighing device 1 can be performed, an efficient weighing operation can be performed.

When the maximum correction value SMax is obtained, in step s35 of FIG. 9, the correction value acquisition unit 821 sorts the weighing hoppers 7 in descending order based on the value of the index α _n and ranks them. Since the index α _n is an index indicating the distribution state of the objects to be weighed in the dispersion direction as described above, this ranking gives a direction in which more objects to be weighed are dispersed than in other dispersion directions. The arranged weighing hopper 7 is ranked higher. Hereinafter, the order of the weighing hopper 7 at this time is assumed to be a rank m (1 ≦ m ≦ N).

Next, in step s36, the correction value acquisition unit 821 sets a correction value for the reference target input weight W _ref for each of all the weighing hoppers 7 based on the maximum correction value SMax acquired by the maximum correction value acquisition unit 820. Calculate. Note that the correction value of the weighing hopper 7 in the rank m (m = 1) is the maximum correction value SMax.

The correction value acquisition unit 821 obtains a correction value S _m for the weighing hopper 7 of the rank _m by the following equation (12).

When the correction value S _m of the weighing hoppers 7 for all rank m is determined, in step s37, the target value calculation unit 822, based on the correction value S _m, below the target apply weight W _ptm weighing hoppers 7 rank m It calculates | requires by Formula (13).

Next, the target value calculator 822 assigns the target input weight W _ptm as the target input weight W _ttn of the corresponding weighing hopper 7 while referring to the ranking based on the index α _n executed in step _s35 . In this way, the target input weight W _ttn to be assigned to each weighing hopper 7 by the target value calculation unit 822 is calculated. Then, the target value calculating unit 822 generates target input weight data 103 indicating each input weight W _ttn assigned to each weighing hopper 7 and writes the target input weight data 103 in the RAM 9.

Here, the processing of steps s34 to s37 will be specifically described by taking as an example a case where the combination weighing device 1 includes N (N = 5) weighing hoppers 7. FIG. 12 is a diagram showing the index α _n of each weighing hopper 7 in this example. In this example, it is assumed that the value of the index β is “0.18”.

  First, when step s34 is executed, since the index β = 0.18, the maximum correction value SMax is obtained as “0.45” by the equation (9).

Next, by executing step s35, the rank m of the N weighing hoppers 7 is determined based on the index α _n . FIG. 13 is a diagram illustrating a result of ranking the weighing hoppers 7 by the correction value acquisition unit 821. As shown in FIG. 13, the weighing hopper 7 having a larger value of the index α _n is ranked higher.

Further, the correction value acquisition unit 821 executes step s36 to sequentially obtain the correction value S _m for the weighing hoppers 7 from rank 1 to rank 5 according to equation (12). Figure 14 is a diagram showing the relationship between the rank m and the correction value S _m. As shown in FIG. 14, in the combination weighing device 1, the correction values S _m of the respective weighing hoppers 7 are obtained so as to be aligned on a straight line determined by the number N of the weighing hoppers 7 and the maximum correction value SMax.

When each correction value S _m is obtained, the target value calculation unit 822 obtains each target input weight W _ptm by Expression (13). Further, the target value calculation unit 822 assigns the _calculated target input weight W _ptm as the target input weight W _ttn of each weighing hopper 7 based on the relationship shown in FIG. In the example shown here, the weighing hopper 7 of rank 1 is the third weighing hopper 7 from the relationship shown in FIG. 13, and therefore the target input weight W _pt1 “1.450 · W _ref ” determined from the correction value S _1. Is assigned to the target input weight W _tt3 of the third weighing hopper 7. Further, since the weighing hopper 7 of the rank 2 is the second weighing hopper 7, the target charging weight W _pt2 “1.225 · W _ref ” obtained from the correction value S ₂ is the target charging of the second weighing hopper 7. Assigned to weight W _tt2 .

FIG. 15 is a diagram showing the target input weight W _ttn assigned to each weighing hopper 7 in this way. FIG. 16 is a diagram illustrating a distribution state of the target input weight W _ttn assigned to each weighing hopper 7 by the target value calculation unit 822. As shown in FIG. 16, in the combination weighing device 1, the value of the index α _n is the largest, and the largest target input weight W for the third weighing hopper 7 determined to have many objects to be weighed. _pt1 is assigned. Conversely, the smallest target input weight W _pt5 is assigned to the first weighing hopper 7 that is determined to have the smallest value of the index α _n and that there is only a small amount of objects to be weighed.

As described above, in the combination weighing device 1, during the weighing operation, the distribution state of the target input weight W _ttn to be assigned to each weighing hopper 7 can be changed according to the distribution state of the weighing object dispersed by the dispersion feeder 3. . Thereby, even when the distribution state of the weighing object is changed by the operation of the combination weighing device 1, the target input weight W _ttn of each weighing hopper 7 can be appropriately assigned.

When the target input weight W _ttn of each weighing hopper 7 is set, the combination weighing device 1 ends the target input weight setting process and returns to the process shown in FIG.

  When the target input weight setting process ends, in step s17, the parameter setting unit 83 generates parameter data 104 based on the target input weight data 103, and changes the conveyance force parameter of each radiation feeder 5.

Parameter setting unit 83 uses the target apply weight W _ttn newly assigned, the correction value E _n for correcting the conveying force parameter of the radiation feeders 5 for conveying the objects to be weighed to the n-th weighing hoppers 7 It calculates | requires by the following formula | equation (14).

Next, the conveyance force parameters (amplitude parameter _An and time parameter Tn) of each radiation feeder 5 are corrected by each correction value En, and new parameter data 104 is generated.

Thereby, when the radiating feeder control unit 88 of the control unit 8 controls each radiating feeder 5 thereafter, the newly generated parameter data 104 is referred to, and the radiating feeder control unit 88 uses the amplitude parameter _An and The n-th radiation feeder 5 can be driven and controlled based on the time parameter T _n .

  When step 17 shown in FIG. 6 is executed, the controller 8 resets the measurement number counter in step s18. In step s19, the control unit 8 determines whether or not the measurement operation is continued. If the measurement operation is continued, step s12 is executed, and thereafter the same operation is repeated.

As described above, in the combination weighing device 1 according to the first embodiment, during the operation of the combination weighing device 1, the situation determination unit 81 determines the distribution state of the objects to be weighed dispersed by the dispersion feeder 3, and the In accordance with the determination result, a target input weight W _ttn, which is the weight of the object to be weighed, is assigned to each weighing hopper 7. Further, by controlling the conveying force of each radiation feeder 5 according to the target input weight W _ttn assigned in this way, the weight of the object to be weighed conveyed to each weighing hopper 7 and the weighing hopper 7 Since an error from the target input weight W _ttn can be suppressed, an efficient weighing operation can be realized.

In particular, the combination weighing device 1 operates by changing the distribution state of the target input weight W _ttn to be assigned to each weighing hopper 7 according to the distribution state between the dispersion directions of the objects to be weighed dispersed by the dispersion feeder 3. Thus, even when the distribution state of the objects to be weighed changes in the dispersion direction, each radiation feeder 5 can be appropriately controlled.

Further, by performing the determination based on the index α _n indicating the variation of the objects to be weighed between the weighing hoppers 7, the distribution state of the objects to be weighed in the dispersion direction can be easily determined.

Further, the target input weight W _ttn of the weighing hopper 7 in the direction in which a relatively large amount of objects to be weighed is dispersed is set to a relatively large value, and the weighing hopper 7 in the direction in which only a relatively small amount of objects to be weighed is dispersed. By _{setting the} target input weight W _ttn to a relatively small value, it is possible to improve the probability that the weight of the object actually transported to the weighing hopper 7 becomes the target input weight W _ttn .

Further, the maximum correction value SMax is acquired according to the variation state of the weighing object conveyed to the weighing hopper 7 for each weighing cycle, and thereby the target input weight W _ttn assigned to each weighing hopper 7 is changed. Thus, more efficient weighing operation can be realized.

  Further, by performing the determination according to the index β indicating the variation for each weighing operation of the weighing object conveyed to the weighing hopper 7, it is possible to easily determine the distribution state of the objects to be weighed in the dispersion direction.

Next, a description will be given reasons for seeking a target selected hoppers number N _st which is a measure of the selected hoppers number N _s as described above.

In general, charged weight W _t distribution N _i of the objects to be weighed for each of the weighing hoppers ^{_{7 (μ i, σ i 2}} ) (i = 1~N, μ i = X n, σ i = σ n) It can be defined by the normal distribution expressed. Then, from the q weighing hoppers 7 takes out the r number of the weighing hoppers 7 number of combinations of (selected for) when is _q C _r, respectively population of combined weight Wc of this time,

It is represented by Here, j means a combination pattern from 1 to _{q Cr} , and “μ ₁ + μ ₂ +... + Μ _r ” in each case is represented by μ _j and “σ ₁ ² + σ ₂ ² +. ... + Σ _r ² ”is σ _j ² , the probability density function f _j (x) of the combination weight x for the population M _j is expressed by the following equation (15).

Therefore, the probability in the range x~x + Δx combination weight p _j (x) is

It becomes. Here, Δx is the weighing resolution with respect to the weight of the objects to be weighed in the combination weighing device 1 and is, for example, 0.1 g.

Since μ _j and σ _j ² exist in k (= _q C _r ) combinations, respectively, the combined weight x in all combinations when taking out the r weighing hoppers 7 from the q weighing hoppers 7 is The probability P _r (x) that exists is

Can be expressed as Accordingly, the probability P _total (where the combined weight x is obtained by all the combinations in the case where r is changed from 1 to q, that is, all the weight combinations when the combination calculation is performed using the q weighing hoppers 7. x) can be expressed as the following formula (18).

Note that the total number N _comb of all weight combinations when the combination calculation is performed using the q weighing hoppers 7 is expressed by the following equation (19).

Thus, the probability P _total (x) indicates the probability that the combination weight x is obtained by the combination calculation performed using the weighing signals from the q weighing hoppers 7. In other words, the probability that the combination weight x is obtained in the combination calculation in which the number of participating hoppers N _p is q is shown.

FIG. 17 is a diagram showing a probability distribution of the combination weight x in the single shift mode, which is obtained by the simulation using the equation (18). FIG. 17 shows a probability distribution when q = 10, that is, the number of participating hoppers N _p is 10, and μ _i = 10 g, that is, all average input weights X _n are 10 g. Further, σ in FIG. 17 represents the ratio of σ _{i to} μ _i , that is, the ratio of the standard deviation σ _{n to} the average input weight X _n , and is expressed by the following equation (20). The value of σ in FIG. 17 is expressed as a percentage.

A solid line, a broken line, a one-dot chain line, and a two-dot chain line in FIG. 17 indicate probability distributions when σ = 5%, 10%, 20%, and 30%, respectively. As shown in FIG. 17, in the single mode, the probability P _total (x) is maximized when the combination weight x is 50 g in all values of σ. In other words, when the target combination weight W _ct is set to 50 g, the probability of obtaining it in the combination calculation is maximized.

Here, since the simulation result shown in FIG. 17 is a result when all the average input weights _Xn are virtually set to 10 g, in this case, if the target combination weight _Wct is set to 50 g, the combination calculation calculates it. If the target input weight W _ttn is the same for all the weighing hoppers 7, the value obtained by dividing the target combination weight W _ct by 5 (= 50 g / 10 g) will be obtained. _{By setting ttn} , the target combination weight W _ct can be obtained efficiently in the actual combination calculation. The number “5” is half the number of participating hoppers N _p .

Similarly, when the probability distribution of the combination weight x is obtained by changing the value of the number of participating hoppers N _p by the simulation using Expression (17), the combination weight x is the average input weight X _{n in} each probability distribution. The probability P _total (x) is maximized when the value is multiplied by half the number of participating hoppers N _p . Thus, in the single shift mode, if the target input weight W _ttn is the same for all the weighing hoppers 7, the target combination weight W _ct is set to the participating hopper number N regardless of the value of the participating hopper number N _{p. It} can be understood that the target combination weight W _ct can be efficiently obtained in the combination calculation by _{setting the} target input weight W _ttn to the value divided by half the value of _p .

Here, in the single shift mode, the number of possible hoppers N _c results in the number of participating hoppers N _p , so the target combination weight W _ct is divided by half the value of the number of possible hoppers N _c. By setting the input weight W _tt , the target combination weight W _ct can be obtained efficiently.

From the above, in the single shift mode, the target selection hoppers number N _st, set to half the value of participable hopper number N _c, reference target as a reference of target apply weight W _ttn of each weighing hopper 7 By obtaining the input weight W _ref by the above formula (8), the combination weight Wc within the allowable range can be efficiently obtained in the combination calculation.

In this way, by setting the target selection hopper number _Nst to a value that is half of the number of possible hoppers _Nc , the average value of the number of weighing hoppers 7 selected based on the result of the combination calculation, that is, the selection The average value of the hopper number N _{s is} a value close to the target selection hopper number N _st . For example, if the participation possible hopper speed N _c is "9", the target selected hoppers number N _st is set to "4.5", this case, the average value of the selected hoppers number N _s "4.5" Nearby. Thus, the target selected hopper number N _st is a guide for the selected hopper number N _s .

Next, a method for deriving the arithmetic expression (5) used when the operation mode data 105 indicates other operation modes will be described. As described above, in the double shift mode and the triple shift mode, the weighing hopper 7 selected in a certain weighing cycle cannot participate in the combination calculation at least in the next weighing cycle. Therefore, depending on the value of the selected hopper number N _s, the number of participating hoppers N _p in the next weighing cycle may be reduced compared to the previous time, and the total number of weight combinations in the combination calculation may be reduced in a plurality of weighing cycles. There is.

For example, when the total number N _total of the weighing hoppers 7 is “14” as in the first embodiment and the double shift mode is considered, when the selected hopper number N _s is “5” in a certain weighing cycle, The number of participating hoppers N _p in the next weighing cycle is “9”. When six weighing hoppers 7 are selected in the weighing cycle, the number of participating hoppers N _p in the next weighing cycle is set to the value obtained by subtracting “6” from “9” and the number of selected hoppers in the previous time. A value obtained by adding “5” which is N _s , that is, “8”. Therefore, the number of participating hoppers N _p “8” in this weighing cycle is smaller than “9” in the previous weighing cycle, and the number of weight combinations in the combination calculation is smaller than the previous time.

As described above, in the double shift mode and the triple shift mode, when the sum of the number of participating hoppers N _p and the number of selected hoppers N _s is larger than the total number N _{total of the} weighing hoppers 7 in a certain weighing cycle. The number of participating hoppers N _p in the next weighing cycle decreases. Therefore, when the total number of weight combinations in the combination calculation is considered in a plurality of weighing cycles, in each weighing cycle, the selected hopper number N _s is a value obtained by subtracting the participating hopper number N _p from the total number N _total of the weighing hoppers 7. The following is desirable.

For example, when the total number N _total of the weighing hoppers 7 and the number of participating hoppers N _p are “14” and “10”, respectively, the selected hopper number N _s in each weighing cycle is preferably “4” or less. Hereinafter, a value obtained by subtracting the participating hopper number N _p from the total number N _total of the weighing hoppers 7 is referred to as “maximum selected hopper number N _smax ”.

Here, the fact that the selected hopper number N _s is less than or equal to the maximum selected hopper number N _smax means that the combination weight Wc within the allowable range is obtained from the combination of the weights having the maximum selected hopper number N _smax or less. Is meant to be. That is, in the combination calculation in each weighing cycle, if the combination weight Wc within the allowable range is obtained from the combination of weights equal to or less than the maximum selected hopper number N _smax , the selected hopper number N _s is always the maximum selected hopper number. N _smax or less, and the number of participating hoppers N _p in the next weighing cycle does not decrease. The total number N _d of weights when the combination calculation is performed using the number of weights equal to or less than the maximum selected hopper number N _smax is expressed by the following equation (21).

Moreover, as it is clear from equation (21), the maximum selected hoppers number N _smax value from changing a combination total N _d, to limit the selection hoppers number N _s to the maximum selected hoppers number N _smax is By _{setting the} maximum selected hopper number N _{smax so} that the total number of combinations N _d becomes the largest, it becomes easy to obtain a combination weight Wc within an allowable range from a combination of weights equal to or less than the maximum selected hopper number N _smax . Accordingly, the target input weight W _ttn is set such that the probability of obtaining a combination weight Wc within the allowable range is increased from the combination of weights equal to or less than the maximum selected hopper number N _smax so that the total number of combinations N _d is the largest. by can select hoppers number N _p is liable to be less than the maximum selected hoppers number N _smax, to suppress the attrition hoppers number N _p in the next weighing cycle. As a result, the combination calculation can be executed efficiently when viewed in total in a plurality of weighing cycles.

FIG. 18 is a diagram showing the relationship between the maximum selected hopper number N _smax and the total number of combinations N _d . Note that “the total number of hoppers” in FIG. 18 means the _total number N _total of the weighing hoppers 7. Further, the triangle mark, the cross mark, the square mark, and the circle mark in FIG. 18 respectively indicate the total number of combinations N _d when the number of participating hoppers N _p is “7” to “10”.

As shown in FIG. 18, when the total number N _total of the weighing hoppers 7 is “14”, the total number of combinations N _d is maximum when the maximum selected hopper number N _smax is “4”. Furthermore, due to problems such as the dispersion feeder 3 and the radiation feeder 5, the plurality of weighing hoppers 7 include empty hoppers in which the objects to be weighed are not charged, and the _total number N _total of the weighing hoppers 7 is apparently “13”, Even when the values are reduced to “12” and “11”, the total number of combinations N _d becomes maximum when the maximum selected hopper number N _smax is “4”.

As described above, when the total number N _total of the weighing hoppers 7 is “14”, even when the total number N _total is apparently lowered to some extent, the total number of combinations when the maximum selected hopper number N _smax is “4”. N _d is maximized. Accordingly, in the double shift mode in which the _total number N _total of the weighing hoppers 7 is “14” as in the first embodiment, the weight of 4 or less is used in the combination calculation where the number of participating hoppers N _p is “10”. By setting the target input weight W _ttn that increases the probability that a combination weight Wc within the allowable range is obtained from the combination, the combination calculation can be performed efficiently.

FIG. 19 is a diagram showing the probability distribution of the combination weight x when only the combination of four or less weights is considered in the combination calculation when the number of participating hoppers N _p is “10”. These are the results of simulation using the following equation (22).

FIG. 19 shows the probability distribution when q = 10 and μ _i = 10 g, as in FIG. Further, the solid line, broken line, one-dot chain line, two-dot chain line, thick solid line, and thick broken line in FIG. 19 represent probability distributions when σ = 5%, 10%, 20%, 30%, 40%, and 50%, respectively. Show.

As shown in FIG. 19, when σ = 5%, the probability P _total (x) becomes maximum when the combined weight x is about 40 g. Then, as σ increases, the value of the combination weight x that maximizes the probability P _total (x) decreases. In addition, the circle in FIG. 19 has shown the maximum value in each curve.

As can be understood from the description in the single shift mode, the target selection hopper number N _st is a value obtained by dividing the combination weight x obtained by the simulation with the maximum probability P _total (x) by μ _i. Thus, the combination weight Wc within the allowable range can be obtained efficiently in the combination calculation. In the double shift mode and the triple shift mode, only the combination of weights equal to or less than the maximum selected hopper number N _smax is considered for the reason described above, and therefore the probability P _total (x) is maximized depending on the value of σ. The value of the combination weight x changes. Therefore, in order to efficiently obtain the combination weight Wc within the allowable range in the combination calculation, it is necessary to change the target selection hopper number _Nst according to the value of σ.

FIG. 19 shows the probability of obtaining the combination weight x. If the combination weight x is regarded as the target combination weight W _ct , FIG. 19 shows the combination calculation when the average input weight X _n is 10 g. It can be said that the probability of obtaining the target combination weight _Wct shown on the horizontal axis is shown. For example, when σ = 5%, the probability of obtaining the target combination weight W _ct “10 g” is about 0.55.

Further, as described above, the total number N _total of the weighing hoppers 7 may seem to decrease due to the generation of the empty weighing hoppers 7. Therefore, in the first embodiment, even if the number of selected hoppers N _s can be limited to “4” or less, the number of participating hoppers N _p may decrease from “10”.

FIG. 20 is a diagram illustrating a probability distribution of the combination weight x when the number of participating hoppers N _p decreases. The probability distribution of FIG. 20 is a probability distribution when only combinations of four or less weights are considered in the combination calculation, similar to that of FIG. 19, and is a result of simulation using the above equation (22).

FIG. 20 shows a probability distribution when μ _i = 10 g and σ = 30%, and the solid line, the broken line, the one-dot chain line and the two-dot chain line in FIG. 20 indicate the number of participating hoppers N _p , that is, the value of q. Are the probability distributions when “10”, “9”, “8”, and “7”, respectively.

As shown in FIG. 20, when the number of participating hoppers N _p decreases, the value of the combination weight x that maximizes the probability P _total (x) also decreases. Therefore, in order to efficiently obtain a combined weight Wc within the allowable range in the combination calculation, it is necessary to also change the target selected hoppers number N _st in accordance with the value of the participating hoppers number N _p. In addition, the circle in FIG. 20 has shown the maximum value in each curve.

From the above, in the double shift mode and the triple shift mode, in order to set the value obtained by dividing the combination weight x with the maximum probability P _total (x) by μ _i as the target selected hopper number N _st , the number of participating hoppers N It is necessary to change the target selection hopper number _Nst according to the values of _p and σ. Therefore, based on the simulation results shown in FIGS. 19 and 20, when the number of participating hoppers N _p is changed, the relationship between the combination weight x and σ that maximizes the probability P _total (x) is obtained. become that way. The diamond mark, square mark, and circle mark in FIG. 21 indicate the combined weight x that maximizes the probability P _total (x) when the number of participating hoppers N _p is “10”, “9”, “8”. Each is shown.

As shown in FIG. 21, in each value of the participation hopper number N _p , the relationship between the combination weight x and σ at which the probability P _total (x) is maximum indicates high linearity. That is, when the target selection hopper number _Nst is set to a value obtained by dividing the combination weight x that maximizes the probability P _total (x) by μ _i , the target selection hopper number Np at each value of the participating hopper numbers N _p The relationship between N _st and σ shows high linearity. Therefore, the linear approximation data shown in FIG. 21, as a parameter the number N _p and σ participate hopper, when obtaining the first-order approximate expression for calculating a target selected hoppers number N _st, the following equation (23) become that way.

Here, the result of FIG. 21 is a simulation result when the average input weight X _n and the standard deviation σ _n are the same value in all the weighing hoppers 7 and the number of participating hoppers N _p is constant. However, in the actual weighing cycle, usually the value of the average introduced weight X _n and the standard deviation sigma _n in all the weighing hoppers 7 are not the same, changes the value of the participating hoppers number N _p. Therefore, in equation (23), adopts the average value N _pp participants hoppers number N _p of above instead of participating hoppers number N _p, the average introduced weight X _n and the average value X instead of the above-mentioned standard deviation sigma _{n By} adopting _t and σ _t , respectively, the target selection hopper number N _st corresponding to the actual operation status of the combination weighing device 1 can be obtained. In the equation (23), the equations obtained by adopting the average values N _pp , X _t , σ _t instead of the participating hopper number N _p , the average input weight X _n and the standard deviation σ _n are the above-mentioned calculations. Equation (5) is obtained.

As described above, in the double shift mode or the triple shift mode when the _total number N _total of the weighing hoppers 7 is 14, the target selection hopper number _Nst is obtained using the arithmetic expression (5), and the obtained target selection hopper number is obtained. By determining the target input weight W _ttn of the object to be weighed using N _st , it becomes easy to obtain a combination weight Wc within an allowable range from a combination of four or less weights in the combination calculation. it is possible to suppress the reduction in the participation hoppers number N _p in weighing cycle, when viewed in total in a plurality of weighing cycle, it is possible to efficiently perform combination calculation.

The probability P _total (x) shown on the vertical axis of FIGS. 19 and 20 indicates the probability of obtaining the combination weight x. If the combination weight x is regarded as the target combination weight W _ct , the target in the combination calculation will be described. It can be said that the probability of obtaining the combination weight _Wct is shown. Therefore, it can be said that the arithmetic expression (5) obtained based on the probability P _total (x) is an expression based on the probability that the target combination weight W _ct is obtained. In addition, since the probability P _total (x) varies depending on σ and the number of participating hoppers N _p , the probability that the target combination weight W _ct is obtained in the combination calculation is the input situation information including the average values X _t and σ _t , the average It can be said that it varies depending on the participation hopper number information including the value N _pp .

As described above, in the combination weighing device 1 according to the first embodiment, the target selection hopper number _Nst is automatically obtained regardless of the operation mode, thereby reducing the operation burden on the user. The target input weight W _ttn of the object to be weighed can be determined.

The target selected hoppers number N _st is the average value X _t, and the put status information including a sigma _t, because it is determined on the basis of the participating hopper number information including the average value N _pp, double shift mode or triple shift mode Even when these pieces of information that affect the probability of obtaining the target combination weight W _ct change, the optimum target selection hopper number _Nst can be automatically obtained. Accordingly, it is possible to determine the optimum target weight W _ttn of the object to be weighed while reducing the operation burden on the user.

Further, in the combination weighing apparatus 1, since by using the calculation equation (5) seeking a target selected hoppers number N _st, can be easily obtained a target selected hoppers number N _st.

In addition, since the calculation formula (5) according to the first embodiment is based on the probability that the target combination weight _Wct is obtained in the combination calculation, the target selection hopper number N _st obtained by the calculation formula (5) is calculated. By determining the target input weight W _ttn of the object to be weighed using, the probability that the target combined weight W _ct can be obtained can be reliably improved.

In the first embodiment, since the method for obtaining the target selected hopper number _Nst is determined based on the condition relating to the capability of the combination weighing device 1 as expressed by the above formula (4), The optimum target selection hopper number _Nst corresponding to the capability of the combination weighing device 1 can be obtained.

Embodiment 2. FIG.
In the combination weighing device 1 according to the above-described first embodiment, the operation mode is determined based on the conditional expression (4), and the weighing signal is stable when determining the weighing hopper 7 to participate in the combination calculation. Therefore, the operation mode indicated by the operation mode data 105 may differ from the actual operation mode as described above. Therefore, there is a case where the method for obtaining the target selection hopper number _Nst does not correspond to the contents of the combination calculation process and is not appropriately selected. For example, when the actual operation mode is the single shift mode but the operation mode data 105 indicates another operation mode, the target selection hopper number _Nst is obtained using the arithmetic expression (5). Therefore, the method for obtaining the target selection hopper number _Nst is not properly selected.

  Therefore, in the second embodiment, the combination weighing device 1 that operates so that the operation mode indicated by the operation mode 105 and the actual operation mode are surely matched is provided.

  FIG. 22 is a block diagram illustrating a configuration of the control unit 8 of the combination weighing device 1 according to Embodiment 2 of the present invention. As shown in FIG. 22, the combination weighing device 1 according to the second embodiment is the combination weighing device 1 according to the first embodiment, in which an operation mode determination unit 185 is provided instead of the operation mode determination unit 85. Further, the contents of the combination calculation process in the hopper control unit 80 are further changed.

  The operation mode determination unit 185 determines whether the combination weighing device 1 operates in the single shift mode, the double shift mode, or the triple shift mode, and uses the data indicating the determination result as the operation mode. Write to the RAM 9 as data 105. Therefore, the operation mode data 105 according to the second embodiment is different from the operation mode data 105 according to the first embodiment indicating the single shift mode and other operation modes, and is different from the single shift mode, the double shift mode, and the triple shift. It will indicate one of the modes.

The hopper selection unit 80 according to the second embodiment reads the operation mode data 105 from the RAM 9 and recognizes the operation mode indicated by the operation mode data 105. Then, the hopper selection unit 80 operates so that the combination calculation process becomes the operation mode indicated by the operation mode data 105. Accordingly, in the second embodiment, the operation mode indicated by the operation mode data 105 matches the actual operation mode, and the method for obtaining the target selection hopper number _Nst is appropriately selected. Below, the combination calculation process of the hopper selection part 80 which concerns on this Embodiment 2 is demonstrated in detail.

When the operation mode data 105 indicates the single shift mode, the hopper selection unit 80 reads the participation hopper number data 108 in the RAM 9 and recognizes the participation hopper number _Nc . Then, the hopper selection unit 80 causes the same number of weighing hoppers 7 as the participation hopper number _Nc to participate in the combination calculation. For example, when the total number N _total of the weighing hoppers 7 and the maximum number of hoppers N _cmax that can be participated are 14 and 10, respectively, the number of hoppers N _c that can participate is 10 and therefore the hopper selection unit 80 has 10 pieces. A combination calculation is performed using the weight of the object to be weighed from the weighing hopper 7. That is, the hopper selection unit 80 considers all combinations of ten weights. At this time, the hopper selection unit 80 causes the weighing hopper 7 to participate in the combination calculation in ascending order of the number of times of participation in the past combination calculation.

Next, the combination calculation when the operation mode data 105 indicates the double shift mode will be described. FIG. 23 is a flowchart showing the combination calculation process at this time. As shown in FIG. 23, in step s51, the hopper selection unit 80 recognizes the weighing hopper 7 that has participated in the previous combination calculation. Since the number of the weighing hopper 7 that participated in the combination calculation is included in the history data 101 and stored in the RAM 9 for each weighing cycle, the hopper selection unit 80 stores the number in the previous combination calculation by referring to the number. The participating weighing hopper 7 can be recognized, and the number of participating hoppers N _p in the previous combination calculation can also be acquired.

Next, in step s52, it is determined whether the following conditional expression (24) is satisfied. The number of participating hoppers N _p in the following conditional expression (24) indicates the number of weighing hoppers 7 that participated in the previous combination calculation.

When the conditional expression (24) is satisfied in step s52, in step s53, the hopper selection unit 80 determines the maximum number of hoppers that can participate from the remainder excluding the weighing hopper 7 that participated in the previous combination calculation. Select the same number of weighing hoppers 7 as N _cmax . At this time, the hopper selection unit 80 selects the weighing hopper 7 in the order of the smallest number of times of participation in the past combination calculation, except for those that participated in the previous combination calculation. In step s54, the hopper selection unit 80 causes the selected weighing hopper 7 to participate in the combination calculation.

  On the other hand, if the conditional expression (24) is not satisfied in step s52, in step s55, the hopper selection unit 80 converts all remaining ones of the weighing hoppers 7 except for those participating in the previous combination calculation to the combination calculation. Let them participate.

Next, the case where the operation mode data 105 indicates the triple shift mode will be described. First, by referring to the history data 101, the hopper selection unit 80 recognizes the weighing hopper 7 that has participated in the previous and previous combination calculations, and the number of participating hoppers N _p in the previous combination calculation and the previous combination calculation. to get the participation hopper number N _p.

Then, the hopper selection unit 80 obtains a value obtained by subtracting a value obtained by adding the number of participating hoppers N _p in the previous combination calculation and the number of participating hoppers N _p in the previous combination calculation from the total number N _total of the weighing hoppers 7. It is determined whether or not it is larger than the maximum participation hopper number _Ncmax , and if it is larger, the maximum number of hoppers that can be participated from the remainder of the weighing hopper 7 excluding those that participated in the previous and previous combination calculations. Select the same number of weighing hoppers 7 as N _cmax . At this time, the hopper selection unit 80 selects the weighing hoppers 7 in the order of the smallest number of times of participation in the past combination calculation, excluding those that participated in the previous and previous combination calculations. Then, the hopper selection unit 80 causes the selected weighing hopper 7 to participate in the combination calculation.

On the other hand, when the above subtracted value is less than or equal to the maximum number of hoppers N _{cmax that} can be participated, the hopper selection unit 80, except for the weighing hoppers 7 except for those that participated in the previous and previous combination calculations. To participate in the combination calculation.

As described above, in the combination weighing device 1 according to the second embodiment, the hopper selection unit 80 performs the combination calculation process according to the operation mode indicated by the operation mode data 105, thereby the operation indicated by the operation mode data 105. The mode matches the actual operation mode. Accordingly, as a method for obtaining the target selection hopper number _Nst , an appropriate method according to the content of the combination calculation process is adopted.

  Next, the operation mode determination process performed by the operation mode determination unit 185 will be described. This operation mode determination process is executed instead of the operation mode determination process described in the first embodiment. That is, the operation mode determination process is executed first in the combination weighing process executed in step s12 of FIG.

FIG. 24 is a flowchart showing the contents of the operation mode determination process. As shown in FIG. 24, in step s61, the operation mode determining unit 185 obtains the time t _z based on the ability data of initializing data in RAM 9. The operation mode determining unit 185 obtains the time t _y in step s62.

  Next, in step s63, the operation mode determination unit 185 determines whether or not the conditional expression (4) is satisfied. That is, the operation mode determination unit 185 functions as a determination unit that determines whether the conditional expression (4) is satisfied.

  When the conditional expression (4) is not satisfied in step s63, the operation mode determination unit 185 determines the operation mode of the combination weighing device 1 to the single shift mode in step s64, and stores the operation mode data 105 indicating the operation mode data 105. Generate and write to RAM 9. On the other hand, when the conditional expression (4) is satisfied in step s63, the operation mode determination unit 185 determines whether or not the following conditional expression (25) is satisfied in step s65.

  When the conditional expression (25) is satisfied in step s65, the operation mode determination unit 185 determines the operation mode of the combination weighing device 1 to the double shift mode in step s66, and the operation mode data 105 indicating this. Is written into the RAM 9. On the other hand, when the conditional expression (25) is not satisfied in step s65, the operation mode determination unit 185 determines the operation mode of the combination weighing device 1 to the triple shift mode in step s67, and the operation mode data indicating it. 105 is generated and written to the RAM 9.

As described above, when the combination weighing device 1 according to the second embodiment, the time t _y than the time t _z large, for timing the weighing signal for executing N _a of times the combination computation per minute When filtering is executed and the combination calculation is started, a measurement signal that is not stable in the combination calculation is used. Therefore, in order to prevent this, the operation mode is set to the double shift mode or the triple shift mode.

When the time _ty is (1 / N _a + t _z ) or more, in order to obtain an accurate combination weight, the weighing hopper 7 selected in a certain weighing cycle is combined not only in the next time but also in the next weighing cycle. Since it is necessary not to participate in the calculation, the operation mode is set to the triple shift mode.

As for the other components operating with reference to the operation mode data 105 described in the first embodiment, the single shift mode is indicated in the first embodiment when the operation mode data 105 indicates the single shift mode. When the double shift mode or the triple shift mode is indicated, the same operation as in the case of the other operation modes in the first embodiment is performed. Therefore, the target selection hopper number _Nst is obtained using the above equation (5) _regardless of _whether the operation mode is the double shift mode or the triple shift mode.

As described above, in the combination weighing device according to the second embodiment, since the actual operation mode matches the operation mode indicated by the operation mode data 105, the content of the combination calculation processing regarding the method for obtaining the target selection hopper number _Nst is described. Appropriate methods according to the situation are surely adopted. Therefore, a more optimal target input weight W _tt can be determined.

Although the combination weighing apparatus 1 according to the second embodiment and the first embodiment described above has 14 heads 4, the number of other heads, for example, 8, 10, 16, 20 heads 4. The present invention can also be applied to the combination weighing device 1 including the above. In these cases, by recalculating the arithmetic expression (5) based on the contents described with reference to FIGS. 18 to 21, the optimum target selection hopper number N can be easily obtained in the double shift mode or the triple shift mode. _st can be obtained.

  Furthermore, the present invention can also be applied to a combination weighing device in which a booster hopper is provided below the weighing hopper 7 like the combination weighing device disclosed in Patent Document 2.

  Moreover, although the said Formula (5) was calculated | required from the formula obtained by carrying out the linear approximation of the data shown in FIG. 21, it is obtained by the approximation by another method, for example, approximation using a quadratic function, an exponential function, etc. You may obtain | require from a type | formula.

In the first and second embodiments, the target selection hopper number _Nst is obtained using the arithmetic expression (5) in the double shift mode or the triple shift mode. However, the control unit 8 performs the weighing operation during the weighing operation. A simulation for obtaining the probability distribution of the combination weight x as shown in FIG. 19 may be executed to obtain the target selection hopper number _Nst without using the arithmetic expression (5). In this case, step s45 of FIG. 10 described above is changed as follows.

In step s45, the control unit 8 executes a simulation using Expression (22) to obtain a probability distribution as shown in FIG. At this time, the average values N _pp , X _t , and σ _t acquired in step s44 are substituted for q, μ _i, and σ _i , respectively. Further, as shown in FIG. 18 described above, the maximum selected hopper number N _smax that maximizes the total number of combinations N _d is included in the initial setting information input by the operator, and the control unit 8 executes the initial setting. The information is read from the RAM 9 and used for the simulation.

Next, the control part 8 _{calculates |} requires the combination weight x from which the probability _Ptotal (x) becomes the maximum from the probability distribution obtained by simulation. The control unit 8, a value obtained by dividing the combined weight x the average value X _t and a target selected hoppers number N _st.

In this way, by executing the simulation during the weighing operation, the control unit 8 can directly determine the target selection hopper number _Nst without using the arithmetic expression (5). As a result, the optimum target selection hopper number _Nst can be obtained as compared with the case where the arithmetic expression (5) which is an approximate expression is used.

1 is a diagram illustrating an overall configuration of a combination weighing device according to a first embodiment. It is a block diagram which shows the structure of the control part which concerns on this Embodiment 1. It is a block diagram which shows the structure of the information acquisition part which concerns on this Embodiment 1. FIG. It is a block diagram which shows the structure of the input weight determination part which concerns on this Embodiment 1. FIG. 4 is a flowchart showing the operation of the combination weighing device according to the first embodiment. 4 is a flowchart showing the operation of the combination weighing device according to the first embodiment. 4 is a flowchart showing the operation of the combination weighing device according to the first embodiment. It is a figure which shows the relationship of the various operation time in the combination weighing | measuring apparatus which concerns on this Embodiment 1. FIG. 4 is a flowchart showing the operation of the combination weighing device according to the first embodiment. 4 is a flowchart showing the operation of the combination weighing device according to the first embodiment. It is a figure which shows the relationship between parameter | index (beta) and the maximum correction value SMax. It is a figure which shows the example of parameter | index (alpha) _n . It is a figure which shows the result of ranking of the measurement hopper by the correction | amendment acquisition part which concerns on this Embodiment 1. FIG. Is a diagram showing the relationship between the rank m and the correction value S _m. It is a figure which shows the target throwing weight allocated to each weighing hopper by the target value calculating part which concerns on this Embodiment 1. FIG. It is a figure which shows the distribution condition of the target throwing weight allocated to each measurement hopper by the target value calculating part which concerns on this Embodiment 1. FIG. It is a figure which shows the probability distribution of combined weight. It is a figure which shows the relationship between the largest selection hopper number and the total number of combinations. It is a figure which shows the probability distribution of combined weight. It is a figure which shows the probability distribution of combined weight. It is a figure which shows the relationship between the combination weight x and (sigma) from which the probability _Ptotal (x) becomes the maximum. It is a block diagram which shows the structure of the control part which concerns on this Embodiment 2. It is a flowchart which shows operation | movement of the combination weighing | measuring apparatus which concerns on this Embodiment 2. FIG. It is a flowchart which shows operation | movement of the combination weighing | measuring apparatus which concerns on this Embodiment 2. FIG.

Explanation of symbols

1 Combination Weighing Device 7 Weighing Hopper 80 Hopper Selection Unit 82 Input Weight Determination Unit 85 Operation Mode Determination Unit 87 Operation Unit 103 Target Input Weight Data 107 Participating Hopper Number Data 108 Participable Hopper Number Data 109 Input Status Data 111 Target Selection Hopper Number Data 185 Operation mode determination unit 860 Participation hopper number acquisition unit 861 Participation hopper number acquisition unit 862 Input status acquisition unit N _c Number of participation hoppers N _p Number of participation hoppers N _pp average value N _s Number of selection hoppers N _st Target selection hopper number W _ttTarget input weight _Xn average input weight _Xt average value σ _n standard deviation σ _t average value

Claims (10)

A plurality of hoppers that are loaded with the objects to be weighed and capable of discharging the charged objects to be weighed;
A weighing unit for weighing each of the objects to be weighed put into the plurality of hoppers;
A hopper selection unit that performs a combination calculation of the weights of the objects weighed by the weighing unit, and selects a hopper that performs a discharge operation among the plurality of hoppers based on a result of the combination calculation;
A participating hopper number acquisition unit that acquires first information regarding the number of hoppers participating in the combination calculation among the plurality of hoppers;
A loading status acquisition unit that acquires second information related to a loading status of the objects to be weighed with respect to the plurality of hoppers;
A calculation unit for obtaining a target selection hopper number as a guide for the number of selection hoppers in the hopper selection unit;
An input weight determination unit that determines a target input weight of the objects to be weighed with respect to the plurality of hoppers using the target selection hopper number;
The combination weighing device, wherein the calculation unit obtains the target selection hopper number based on the first and second information. The combination weighing device according to claim 1,
A determination unit for determining whether or not a predetermined condition relating to the capability of the combination weighing device is satisfied;
The combination weighing device, wherein the calculation unit obtains the target selection hopper number based on the first and second information when the determination unit satisfies the predetermined condition. The combination weighing device according to claim 2,
The combination weighing device, wherein when the predetermined condition is satisfied in the determination unit, the hopper selected by the hopper selection unit is not allowed to participate in at least the combination calculation in the next weighing cycle. A plurality of hoppers that are loaded with the objects to be weighed and capable of discharging the charged objects to be weighed;
A weighing unit for weighing each of the objects to be weighed put into the plurality of hoppers;
A hopper selection unit that performs a combination calculation of the weights of the objects weighed by the weighing unit, and selects a hopper that performs a discharge operation among the plurality of hoppers based on a result of the combination calculation;
Participating hopper number acquisition unit for acquiring the number of hoppers that can participate in the combination calculation;
A calculation unit for obtaining a target selection hopper number as a guide for the number of selection hoppers in the hopper selection unit;
An input weight determination unit that determines a target input weight of the objects to be weighed with respect to the plurality of hoppers using the target selection hopper number;
The combination weighing device according to claim 1, wherein the calculation unit obtains a value that is half the number of hoppers that can participate in the combination calculation, and sets the half value as the value of the number of target selection hoppers. The combination weighing device according to claim 4,
A participating hopper number acquisition unit that acquires first information regarding the number of hoppers participating in the combination calculation among the plurality of hoppers;
A loading status acquisition unit that acquires second information related to a loading status of the objects to be weighed with respect to the plurality of hoppers;
A determination unit that determines whether or not a predetermined condition regarding the capability of the combination weighing device is satisfied,
The computing unit is
If the predetermined condition is satisfied in the determination unit, the target selection hopper number is obtained based on the first and second information,
If the predetermined condition is not satisfied in the determination unit, a value half of the number of hoppers that can participate in the combination calculation is obtained, and the half value is set as the value of the target selection hopper number. Combination weighing device to do. The combination weighing device according to claim 5,
When the predetermined condition is satisfied in the determination unit, the hopper selected by the hopper selection unit is not allowed to participate in at least the combination calculation in the next weighing cycle,
When the predetermined condition is not satisfied in the determination unit, the number of hoppers that can participate in combination calculation in two consecutive weighing cycles matches. A combination weighing device according to any one of claims 1, 2, 4, and 5,
A weight stability determination unit that determines the stability of the weight of the object weighed by the weighing unit;
The hopper selection unit performs the combination calculation using only a stable weight among the weights of the objects to be weighed measured by the weighing unit based on a determination result by the weight stability determining unit. Characteristic combination weighing device. A combination weighing device according to any one of claims 1 and 5,
The first information includes an average value of the number of hoppers participating in the combination calculation,
The second information includes third information based on an average value and a standard deviation of input weights of the objects to be weighed with respect to the plurality of hoppers,
The calculation unit obtains the target selection hopper number using an arithmetic expression including a parameter into which the third information and an average value of the number of hoppers participating in the combination calculation are substituted. Weighing device. A combination weighing device according to claim 8,
The combination weighing apparatus according to claim 3, wherein the third information is an average value and an average value of the input weights of the objects to be weighed in each of the plurality of hoppers and an average value between the plurality of hoppers. A combination weighing device according to any one of claims 8 and 9,
The combination weighing apparatus according to claim 1, wherein the calculation formula is based on a probability that a target combination weight is obtained in the combination calculation.

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