JP2011196762A - Combination weighing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform weighing accuracy measurement in each weighing hopper and easily grasping an abnormal operation cycle during combination weighing processing.SOLUTION: A combination weighing apparatus includes: a calculation part 12 holding weighing values for a prescribed number of measurement times when a master work having a known weight is weighed by a weighing hopper 5 operating in a weighing cycle, and calculating the repetition accuracy of the weighing hopper supplied with the master work at the time of reaching the number of measurement times; and a propriety determination part 15 determining the propriety of whether the weighing hopper 5 supplied with the master work performs normal weighing on the basis of an accuracy calculation value based on the repetition accuracy calculated by the calculation part 12 and a propriety determination value set in advance.

Description

  The present invention relates to a combination weighing device that collects and discharges a combination of objects to be weighed that are put into a plurality of hoppers and are weighed out to be in a target weight range.

  In general, a combination weighing device distributes and weighs the objects to be weighed in individual weights to a plurality of weighing units, and measures the total weight among the combinations of the items weighed by each weighing unit. In this configuration, an inner combination is selected, and the objects to be weighed selected for the combination are collectively discharged.

  The general combination weighing device shown in FIG. 8 includes a dispersion supply unit 51 that supplies an object to be weighed and distributes it radially, a plurality of stock hoppers 52 arranged in a circumferential shape, and a plurality of stock hoppers 52 provided below the stock hopper 52. A weighing hopper 53 and a funnel-shaped collecting chute 54 provided at the lower portion of the weighing hopper 53 are provided.

When the objects to be weighed are thrown into the dispersion supply unit 51, they are radially dispersed by the central dispersion unit 51a, conveyed to the stock hopper 52 portion by the vibration of the conveyance unit 51b, and then substantially the same amount via the stock hopper 52. Each is dropped into each weighing hopper 53 and the mass is measured. The weighing values in the plurality of weighing hoppers 53 usually vary to some extent. Therefore, the weighing hopper 53 that satisfies a desired mass value (target mass) by appropriately combining a plurality of weighing values obtained by the plurality of weighing hoppers 53. Are selectively operated to drop the objects to be weighed onto the collecting chute 54. A discharge hopper (not shown) is provided at the lowest part of the collecting chute 54, and the objects to be weighed that have dropped from the plurality of weighing hoppers 53 are collected here. On the other hand, for the weighing hopper 53 that is selectively activated and empty, a new object to be weighed is supplied to the weighing hopper 53 from the corresponding conveying unit via the stock hopper 52 and another weighing hopper 53 is provided. The combination by 53 is selected, and it prepares for the discharge | emission request | requirement signal from the packaging apparatus which packages the to-be-measured object weighed in combination. Then, when the discharge request signal from the packaging device is dropped onto the packaging device from the discharge hopper, the object to be weighed can be packed in the unit of the target weight, and the above series of operations is repeated each time the discharge request signal is input. Then, the objects to be weighed with the target weight are sequentially discharged.
In addition, the operation cycle in which the combination weighing device performs the combination discharge operation is based on the time for opening / closing and weighing the weighing hopper 53 and the time for opening / closing the stock hopper 52 above the weighing hopper 53 with respect to the capacity for weighing the objects to be weighed. It is determined by the weighing cycle in which the object to be measured can be measured stably and the time related to the opening and closing of the discharge hopper that is opened and closed by the discharge request signal.

  Further, in this type of combination weighing device, a configuration (for example, Patent Document 1 below) for determining whether or not each scale normally measures using a weight of a certain weight with respect to the scale provided for each weighing hopper, An apparatus having a configuration (for example, Patent Document 2 below) is also known in which an object to be weighed after combination weighing is weighed by a weight checker and the quality is determined.

JP-A-60-52722 JP 2000-205936 A

  However, in the apparatus disclosed in Patent Document 1, for example, when the apparatus is introduced, the sensitivity of each scale is set using a reference weight, but after the sensitivity is set, combination weighing is performed due to the complexity of the accuracy check work. The current situation is that the weighing accuracy of the balance has not been investigated unless an abnormality occurs in the product, which has affected the measurement accuracy.

  Further, in the configuration in which the objects to be weighed arbitrarily combined and weighed so as to be within the target weight range, as in the apparatus disclosed in Patent Document 2, when a weighing error occurs in a certain scale, It is impossible to determine which scale has an abnormality, and when this scale is specified, the weighing accuracy of each scale has to be determined using a weight as in Patent Document 1.

  Further, in the apparatus of each of the above publications, when performing sensitivity setting, in order to make the weighing hopper stand still with the weighing hopper closed, the weighing accuracy must be measured while the operation cycle including the weighing cycle is stopped. In cases where the weighing accuracy is normal, but defective items occur in the weighed objects that are weighed in combination due to an abnormality in the weighing cycle, the operator cannot grasp this problem and wastes time to solve the problem. It was necessary.

  Accordingly, the present invention has been made in view of the above problems, and provides a combination weighing device that can easily determine whether or not the weighing accuracy of each weighing hopper is good and can easily grasp the abnormality of the weighing cycle. It is intended to do.

In order to achieve the above-described object, the combination weighing device according to claim 1 distributes and supplies the objects to be weighed W having variations in individual weights to a plurality of hoppers and supplies them to the weighing hoppers 5 of each system. A combination for selecting a combination that falls within a target weight range by combining measurement values obtained by weighing the objects to be measured in a predetermined measurement cycle that is set in advance, and discharging the objects to be measured selected in the combination. In the weighing device 1,
A measurement value obtained when a master workpiece of a known weight is measured by a weighing hopper operating in the weighing cycle is held for a preset number of measurements, and when the measurement number is reached, the weighing hopper to which the master workpiece is supplied A calculation unit 12 for calculating repetition accuracy;
Based on the accuracy calculation value based on the repetition accuracy calculated by the calculation unit and a predetermined quality determination value, it is determined whether the weighing hopper supplied with the master work is measuring normally or not. A determination unit 15;
It is provided with.

The combination weighing device according to claim 2 is the combination weighing device according to claim 1, further comprising: the weighing hopper 5 that calculates the repeatability by the master work; and the input setting unit 16 that sets the weight of the master work.
It is characterized in that it is judged whether the repeatability of the weighing hopper set by the input setting unit is good or bad.

The combination weighing device according to claim 3 is the combination weighing device according to claim 1, further comprising a master workpiece identification unit 20 for identifying a known weight of the master workpiece supplied to each weighing hopper 5 of the plurality of systems.
The pass / fail judgment unit 15 judges pass / fail accuracy based on the weight identified by the master work discriminating unit.

A combination weighing device according to a fourth aspect of the present invention includes the combination weighing device according to any one of the first to third aspects, including a quality determination result obtained by the quality determination unit 15 and a quality determination history based on the quality determination result. A storage unit 15 for storing accuracy measurement detailed information;
A display control unit 18 that controls the display unit 19 to display the details of the accuracy measurement detailed information stored in the storage unit;
It is provided with.

  According to the combination weighing device of the present invention, since the weighing accuracy of each weighing hopper is measured in the weighing cycle under the same conditions as in the actual operation, which is the time of the combination weighing process, abnormalities related to various processing times of the operating cycle during operation It becomes easy to guess.

  Furthermore, since the repeatability of each weighing hopper is measured, it is possible to easily determine signs of aging of each weighing hopper and replacement of parts by referring to the pass / fail judgment history during periodic inspection. Play.

1 is a schematic configuration diagram of a combination weighing device according to the present invention. It is a system block diagram which shows the 1st form of the apparatus. It is a timing diagram which shows the operation timing of the apparatus. It is explanatory drawing which shows the example of a display of the apparatus. It is explanatory drawing which shows the example of a display of the apparatus. It is explanatory drawing which shows the example of a display of the apparatus. It is a system block diagram which shows the 2nd form of the combination weighing | measuring apparatus which concerns on this invention. It is the schematic which shows the conventional combination weighing device.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the present invention is not limited by this embodiment, and all other forms, examples, operation techniques, etc. that can be implemented by those skilled in the art based on this form are included in the scope of the present invention. .

The combination weighing device according to the present embodiment measures a product, which is an object to be weighed in an individual weight, with a plurality of weighing hoppers, and within a target weight range from a combination of objects to be weighed with each weighing hopper. A combination is selected, and the selected objects to be weighed are collected and discharged as objects to be weighed within a desired weight range.
In the combination weighing device of this example, the master work, which is an object to be weighed, is weighed by the weighing hopper, the repeatability is calculated using the measured weight value for a predetermined number of times, and each weighing hopper is measured. It has a repeatability calculation function for measuring the weighing accuracy and a pass / fail judgment function for judging an abnormality in the weighing accuracy of each weighing hopper.

[Outline of device]
First, the device configuration of the combination weighing device according to the present invention will be described with reference to FIG. In the same figure, the flow of the to-be-measured object W in one certain system is shown among the several systems of hoppers which perform combination weighing.

  As shown in FIG. 1, the dispersion | distribution part 2a which rotates or vibrates is provided in the upper part of the combination weighing | measuring apparatus 1 of this example, and the position directly under the dropping location of the to-be-measured object W conveyed by conveyance means 8, such as a conveyor. A distributed supply unit 2 is provided. The objects to be weighed W supplied to the dispersion supply unit 2 are always stacked on the dispersion unit 2a with a predetermined angle of repose, and are supplied by being spilled evenly around by the rotation or vibration of the dispersion unit 2a. .

  Around the dispersion unit 2a, a plurality of troughs 3 provided with driving means that reciprocate in the transport direction and linearly move are arranged radially at equal angular intervals in the circumferential direction with the dispersion supply unit 2 as the center. The stock hoppers 4 are respectively arranged below the outer end portions of the troughs 3, and the objects to be weighed W fall from the outer end portions of the outer sides of the troughs 3 and are distributedly supplied to the stock hoppers 4. .

  Below each stock hopper 4, a weighing hopper 5 is arranged, and the stock hopper 4 and the weighing hopper 5 arranged vertically constitute a pair. The objects to be weighed W distributed and supplied to the stock hoppers 4 are supplied to the weighing hoppers 5 that make a pair. The objects to be weighed W supplied to the weighing hopper 5 are weighed by respective weighing units described later, and a combination close to a target predetermined weight is selected based on the measured value from each weighing unit. The objects to be weighed W selected for the combination are discharged from the weighing hopper 5 to the funnel type collecting chute 6 all at once, and once collected in the discharge hopper 7, the lower discharge door 7a is opened. And discharged to a lower apparatus (for example, a packaging machine).

[First form]
<System configuration>
Next, the configuration of the combination weighing device 1 according to the first embodiment will be described. As shown in FIG. 2, the combination weighing device 1 of the first form includes a weighing unit 11, a calculation unit 12, a hopper control unit 13, a storage unit 14, a pass / fail judgment unit 15, an input setting unit 16, a display control unit 17, and a display. A part 18 is schematically configured.

  In this embodiment, there are an operation mode and an accuracy measurement mode as operation modes when the combination weighing device 1 is operated, and the operation mode is a target by combination weighing according to an operation cycle set in advance for an object to be weighed W as a product. A mode for performing a combination weighing process for obtaining a heavy object to be weighed, and an accuracy measurement mode are those in which a master work is conveyed in a weighing cycle under the same conditions as the operation mode and is weighed by a weighing hopper 5 set in advance. Each mode is defined as a mode for performing processing for calculating the repeatability based on the measured value of a certain master work.

  The weighing unit 11 is configured by a weight detector such as a load cell, for example, and is provided in each weighing hopper 5. When the operation mode is the operation mode, the weighing unit 11 outputs the measurement value of the object to be weighed W (that is, the product) to the combination calculation unit 12a described later, and supplies the measurement value when the operation mode is the accuracy measurement mode. The measured value of the measured object W (that is, the master work) is output to the repetition accuracy calculating means 12b described later.

  The calculation unit 12 includes a combination calculation unit 12a and a repetition accuracy calculation unit 12b. Based on the measurement value from the measurement unit 11, the calculation unit 12 performs a combination calculation process related to normal combination weighing or the measurement accuracy measurement of the weighing hopper 5. Measurement calculation processing is performed.

When the combination calculation means 12 a inputs the measurement value of the object to be weighed W as a product from each weighing unit 11, the measurement value of the object to be weighed W measured by each weighing unit 11 is stored in the storage unit 14. A combination of the weighing hoppers 5 is selected so as to be within the range, and hopper setting information indicating the weighing hopper 5 selected at that time is output to the hopper control unit 13.
In other words, the combination calculation means 12a functions only when the operation mode is the operation mode, and calculates the combination of the measurement values from the respective weighing units 11 so that the operation weight is within the preset target weight range, and the appropriate weighing hopper 5 is obtained. Selected.

When the repeatability calculation means 12b receives the measurement value of the workpiece W, which is the master work, from the weighing unit 11, the measurement value from the set weighing hopper 5 is set based on the measurement number information stored in the storage unit 14. Is stored for the number of measurements based on the measurement count information, and the repeatability (variation accuracy (standard deviation) or average value and true value) of the weighing hopper 5 set using the measured value held when the measurement count is reached. Difference (bias)) is calculated. Then, the repeat accuracy calculation means 12b outputs the calculated result (variation accuracy value or bias value) to the pass / fail determination unit 15 as an accuracy calculation value, and sets hopper setting information indicating the set weighing hopper 5 to the hopper control unit 13. Output to.
That is, the repeatability calculation means 12b functions only when the operation mode is the accuracy measurement mode, and uses the measured value of the master workpiece having a known weight as the workpiece W to set the repeatability of the weighing hopper 5 ( Standard deviation or bias) is calculated.

  The hopper control unit 13 determines each hopper (stock hopper 4 based on the weighing cycle corresponding to the object W to be weighed in advance based on the packaging device and the object W information and the hopper setting information from the calculation unit 12. The opening / closing control of the weighing hopper 5 and the discharge hopper 7) is performed. In the operation mode, the weighing hopper 5 is controlled by opening / closing only the weighing hopper 5 selected based on the hopper setting information from the calculation unit 12, so that the weighing hopper 5 is opened / closed each time depending on the combination that becomes the target weight. The weighing hopper 5 to be controlled is different.

  Here, the operation timing in each hopper will be described. The operation timing of the combination weighing device 1 is synchronized with an activation signal input at intervals of an operation cycle T corresponding to the object to be weighed W as shown in FIG. The stock hopper 4 has a delay time T1 from the previous opening / closing of the weighing hopper 5 (the stock hopper 4 starts to open after the weighing hopper 5 starts to close and the object W to be weighed is shown in FIG. The stock hopper 4 is opened / closed at an opening / closing time Ta at a timing delayed by the time until reaching 5), and the next object W is supplied. In addition, the time from when the stock hopper 4 starts to open until the workpiece W is completely discharged to the weighing hopper 5 and measurement is started by the weighing hopper 5 is defined as a stable time Tc. As shown in (c) of the figure, the weighing hopper 5 selects the combination after measuring the workpiece W from the stock hopper 4 with the measurement time Td, and corresponds to the previous opening and closing time of the discharge hopper 7. Then, it opens and closes at the opening and closing time Tb, and the object to be weighed W is completely discharged to the collecting chute 6. The time from the opening and closing of the weighing hopper 5 to the next opening and closing is a weighing cycle Tw (Tc + Td + Tb) in which the workpiece W can be stably measured.

  Further, as shown in FIG. 4D, the discharge hopper 7 has a delay time T2 from the input of the activation signal (the top of the weighing object W reaches the discharge hopper 7 in the shortest time after the weighing hopper 5 starts to open). When the discharge hopper 7 is delayed by a maximum delay time for completely closing the discharge hopper 7 and the discharge hopper 7 is opened / closed at the opening / closing time Te, the workpiece W is moved immediately after the arrival time width Wa of the workpiece W The next opening / closing operation is started in response to a period of (the difference between the longest arrival time and the shortest arrival time when the workpiece W reaches the discharge hopper 7) and the opening / closing time Tb of the weighing hopper 5. Thereafter, the same operation is repeated, and a target amount of the object to be weighed W is discharged every operation cycle T. The start signal is generated by the discharge request signal from the packaging device in the operation mode, and is automatically generated internally in other modes. Therefore, in the operation mode, the discharge signal is discharged by the discharge hopper 7 by the discharge request signal from the packaging device. Operation is performed.

  The storage unit 14 is configured by a storage device such as a semiconductor memory such as a ROM, a RAM, or an EEPROM, or an HDD, for example, information on a target weight of the object to be weighed in advance, equipment environment and information on the object W to be weighed Based on the shape and weight of the object W and the ease of conveyance by the conveyance means 8), information on the operation cycle corresponding to the object W to be weighed in advance by tests or the like, and the repetition accuracy with the set weighing hopper 5 are obtained. Information on the number of times of measurement indicating the number of times of measurement to be performed, and a comparison value for quality determination (for example, variation) that is a comparison target when determining the quality of the accuracy calculation value (variation accuracy value or bias value) calculated by the calculation unit 12 If the accuracy value is acceptable, the acceptable accuracy is ± 0.05 g, and if it is a bias value, the acceptable accuracy is ± 0.1 g), and the quality determination result and the quality determination result regarding each weighing hopper 5 and the operation cycle determined by the quality determination unit 15. Based on Accuracy measurement detail information including the pass / fail judgment history (operator name, measurement date / time, weight of master work, measurement time, open / close time of each hopper, stabilization time, pass / fail judgment comparison value as the pass / fail judgment value, etc.) In addition, control information necessary for driving the combination weighing device 1 is stored.

  The pass / fail determination unit 15 determines whether or not the weighing hopper 5 set based on the accuracy calculated value calculated by the calculation unit 12 and the pass / fail determination comparison value stored in the storage unit 14 is normally weighed. Is determined and the determination result is output to the storage unit 14. Further, when the pass / fail determination unit 15 determines that the pass / fail determination results for all the weighing hoppers 5 included in the apparatus are all normal, the determination result is output to the storage unit 14.

  The input setting unit 16 includes various keys such as a setting key and a numeric keypad, for example. The input setting unit 16 is an input setting related to an operation mode (operation mode or accuracy measurement mode) when driving the apparatus, an input setting related to a target weight or a comparison value for pass / fail judgment, an input setting related to the number of measurements in the accuracy measurement mode, and an accuracy measurement. In addition to the input setting of the hopper setting information indicating the target weighing hopper 5, a predetermined operation is performed when various setting information necessary for driving the combination weighing device 1 is input, and an operation signal based on this operation is output to the corresponding units. is doing.

  The display control unit 17 controls display of various settings set by the input setting unit 16 on a display unit 18 (for example, a display device such as a CRT (Cathode Ray Tube) display or LCD (Liquid Crystal Display)). The display control unit 17 controls the display of the details of the accuracy measurement detailed information stored in the storage unit 14 based on the operation signal from the input setting unit 16. Specific examples of display contents include a system (channel) in which accuracy is confirmed as shown in FIG. 4 and a pass / fail judgment history to be displayed together with the time at which the result was conducted, and an implementation in which accuracy is confirmed as shown in FIG. 7 is a detailed display of the pass / fail judgment history including the display of the operator and the measurement history contents in the weighing hopper selected by the operator as shown in FIG.

<Processing operation>
Next, the processing operation in the combination weighing device 1 of the first embodiment described above will be described. Here, the processing operation in the operation mode for combining and weighing the products that are the objects to be weighed W, and the processing operation in the accuracy measurement mode for obtaining the repeatability of the weighing hopper 5 selected using the master work as the object to be weighed W, respectively. explain.

(Processing in operation mode)
In the operation mode, first, a predetermined operation from the input setting unit 16 of the operator sets a target weight of a product to be weighed in combination, an operation cycle based on product weighing information and a request signal from the packaging device, and an object to be weighed. Carry the product as W.

  The conveyed product is supplied to the distributed supply unit 2 and then supplied to the stock hopper 4 through the trough 3. The product supplied to the stock hopper 4 is controlled to open and close at a timing according to the operation cycle, and the stocked product is supplied to the weighing hopper 5 and weighed by the weighing unit 11 installed in the weighing hopper 5. Then, the measured value of the weighed product is output to the combination calculation unit 12a.

  The combination calculation means 12a selects a combination of the weighing hoppers 5 so that the product weight value measured by each weighing unit 11 is stored in the storage unit 14 so that the product is within the target weight range. The hopper setting information indicating the weighing hopper 5 is output to the hopper control unit 13. The hopper control unit 13 controls the opening and closing of the weighing hopper 5 corresponding to the hopper setting information from the weighing unit 11 at a timing based on the operation cycle, and discharges it to the collective chute 6. The products weighed in combination are discharged to the discharge hopper 7 through the collecting chute 6 and discharged from the discharge hopper 7 by a discharge request signal from the packaging device.

(Processing in accuracy measurement mode)
In the accuracy measurement mode, first, the operation mode is set to the accuracy measurement mode by a predetermined operation from the input setting unit 16 of the operator, and a master work having a known weight is transported as an object to be weighed W in the measurement cycle under the same conditions as the operation mode. .

  The master work is supplied to the trough 3 and then supplied from the trough 3 to the stock hopper 4. The master work supplied to the stock hopper 4 is controlled by opening and closing at a timing according to the weighing cycle, and the stocked master work is supplied to the weighing hopper 5 and weighed by the weighing unit 11 installed in the weighing hopper 5. . Then, the measured value of the master work is output to the repetition accuracy calculation means 12b. Here, when the weighing hopper 5 is empty (when there is no master work), the opening / closing control is performed. However, if there is a master work when the measured weight value is equal to or greater than a predetermined value (when the weighing hopper 5 is not empty), to decide. Note that the opening / closing control of the weighing hopper 5 to which the hopper setting information from the input setting unit 16 is not input is not performed.

  Based on the measurement value from the weighing hopper 5 and the measurement number information stored in the storage unit 14, the repeat accuracy calculation means 12b holds the set measurement value from the measurement hopper 5 for the number of measurement times based on the measurement number information. The repetition accuracy of the weighing hopper 5 set using the measured value held when the number of measurements is reached is calculated. Then, the repeat accuracy calculation unit 12b outputs the calculated result (variation accuracy value or bias value) to the pass / fail determination unit 15 as an accuracy calculation value.

  The pass / fail judgment unit 15 is set by comparing the accuracy calculated value calculated by the calculation unit 12 with the pass / fail judgment comparison value stored in the storage unit 14 and whether or not the difference is within a preset range. Then, it is determined whether or not the weighing hopper 5 is measuring normally, and the determination result is output to the storage unit 14.

  And the operator can grasp | ascertain the presence or absence of the measurement precision of each measurement hopper 5 by confirming the precision measurement detailed information memorize | stored in the memory | storage part 14 with the display part 18. FIG. In addition, when the measurement accuracy results of all the weighing hoppers 5 are good, but outside the target weight range, the weighing cycle is abnormal (the open / close time of each hopper, the object to be weighed W drops from the stock hopper 4). Any abnormality of the falling time, the stable time until all the objects W enter the weighing hopper 5, and the measurement time for measuring the objects W in the weighing hopper 5) can be inferred.

[Second form]
Next, a combination weighing device 1 according to a second embodiment of the present invention will be described with reference to FIG. In the combination weighing device 1 of the second embodiment described below, the same components as those of the combination weighing device 1 of the first embodiment described above are denoted by the same reference numerals, the description thereof is omitted, and the different component requirements. Only will be described.

  The combination weighing device 1 of the second embodiment has an operation mode and a total discharge accuracy measurement mode as operation modes when the combination weighing device 1 is operated, and the operation mode is a mode similar to the combination weighing device 1 of the first embodiment, In the total discharge accuracy measurement mode, when a master work with a plurality of weights is transferred in the weighing cycle under the same conditions as the operation mode, the object W (that is, the master work) is supplied from the trough 3 to the stock hopper 4. This is defined as a mode in which a known weight of an object W to be weighed is identified and processing for calculating repeatability based on a measured value of a master work measured by the weighing hopper 5 is performed. Further, in the input setting unit 16, the setting of the total discharge accuracy measurement mode is added to the operation mode when driving the apparatus.

  In the combination weighing device 1 of the second embodiment, as a new configuration requirement, an object detection unit 21 that detects the object to be measured 11 to be conveyed, and an object that has been conveyed based on detection information from the object to be weighed detection unit 21. A master work identification unit 20 including an article identification unit 22 that identifies a known weight of the weighing object W is provided.

<System configuration>
The to-be-measured object detection part 21 is comprised with imaging devices, such as a CCD camera, images the to-be-measured object W when it is supplied to the stock hopper 4 from the trough 3, The image data of this imaged to-be-measured object W is goods. The data is output to the identification unit 22.

  The article identification unit 22 analyzes the image data from the object detection unit 21 and analyzes the analyzed image data and the image identification information stored in the storage unit 14 (at least one of color information and shape information of the master work). And the known weight of the object to be weighed W that has been conveyed in comparison to the known weight is output, and the known weight that is the identification result is output to the storage unit 14.

  In addition, the article identification unit 22 updates the pass / fail judgment comparison value stored in the storage unit 14 based on the known weight of the master work indicating the identification result and the measurement count information stored in the storage unit 14. In addition, as the update of the pass / fail judgment value, for example, every time the known weight of the identification result is obtained, the average of the known weights so far may be updated as the pass / fail judgment comparison value. When the average value is reached, the average value of the known weights for the number of times of measurement may be updated as a pass / fail judgment comparison value.

  Further, the weighing unit 11 in the second embodiment outputs the measured value to the repeatability calculating means 12b when the measured measured value is equal to or greater than a predetermined value (when the weighing hopper 5 is not empty).

  Further, when the repeatability calculation means 12b in the second embodiment inputs the measurement value of the workpiece W as the master work from the measurement unit 11, the article identification unit 22 is based on the measurement number information stored in the storage unit 14. The measurement value from the weighing hopper 5 to which the workpiece W identified as the master work is supplied is held for the number of measurement times based on the measurement number information, and the measurement value held when the measurement number is reached is used. The repetition accuracy of the weighing hopper 5 is calculated, and the calculation result is output to the pass / fail judgment unit 15 as an accuracy calculation value.

<Processing operation>
Next, the processing operation in the combination weighing device 1 of the second embodiment described above will be described. In the total discharge accuracy measurement mode, first, the number of times of repeat accuracy is set by a predetermined operation from the input setting unit 16 of the operator, and the operation mode is set to the full discharge accuracy measurement mode. A plurality of known weight master workpieces are conveyed in a weighing cycle.

  The conveyed master work is supplied to the distributed supply unit 2 and then supplied to the stock hopper 4 through the trough 3. The master work supplied to the stock hopper 4 is controlled to open and close at a timing according to the weighing cycle, and the master work stocked is supplied to the weighing hopper 5. At this time, when the article is supplied from the trough 3 to the stock hopper 4, the article identification unit 22 collates the image data captured by the object detection unit 21 and the image identification information stored in the storage unit 14. Is output to the storage unit 14.

  The weighing unit 11 outputs the measured measurement value to the repeatability calculation means 12b when the measured measurement value is equal to or greater than a predetermined value (when the measurement hopper 5 is not empty). In addition, the article identification unit 22 updates the pass / fail judgment comparison value stored in the storage unit 14 based on the known weight of the master work indicating the identification result and the measurement count information stored in the storage unit 14.

  The repeatability calculation means 12b is based on the measured value of the master work measured by the weighing unit 11 of the weighing hopper 5 to which the workpiece W as the master work has been supplied and the measurement number information stored in the storage unit 14. The measurement value from the weighing hopper 5 supplied with the workpiece is held for the number of measurement times based on the measurement number information, and when the measurement number is reached, the repetition accuracy of the measurement hopper 5 is calculated, and the repetition accuracy obtained by the calculation The calculation result (variation accuracy value or bias value) is output to the pass / fail judgment unit 15 as the accuracy calculation value.

  The pass / fail determination unit 15 compares the accuracy calculated value calculated by the calculation unit 12 with the pass / fail determination comparison value stored in the storage unit 14 and determines whether the difference is within a preset range. It is determined whether or not the weighing hopper 5 to which the workpiece W to be weighed is being weighed normally is output, and the determination result is output to the storage unit 14.

  And the operator can grasp | ascertain the presence or absence of the measurement precision of each measurement hopper 5 by confirming the precision measurement detailed information memorize | stored in the memory | storage part 14 with the display part 18. FIG. In addition, when the measurement accuracy results of all the weighing hoppers 5 are good, but outside the target weight range, the weighing cycle is abnormal (the open / close time of each hopper, the object to be weighed W drops from the stock hopper 4). Any abnormality of the falling time, the stable time until all the objects W enter the weighing hopper 5, and the measurement time for measuring the objects W in the weighing hopper 5) can be inferred.

  As described above, the combination weighing apparatus 1 according to the first embodiment described above sets the operation mode to the accuracy measurement mode from the input setting unit 16 and is known as the object to be weighed W in the weighing cycle under the same conditions as in the operation mode. Transport the master work. The transferred master work is supplied to the weighing hopper 5 via the stock hopper 4, and only the measured value of the master work measured by the weighing unit 11 having inputted the hopper setting information from the input setting unit 16 is repeatedly sent to the accuracy calculating means 12b. Output. Then, the repeat accuracy of the selected weighing hopper 5 is calculated based on the hopper setting information from the input setting unit 16 and the measurement number information stored in the storage unit 14, and the accuracy calculation value as the calculation result and the storage unit 14 are calculated. Whether or not the weighing hopper 5 selected based on the comparison value for quality determination stored in FIG.

  As a result, since the weighing accuracy is dynamically measured in the weighing cycle under the same conditions as in the combination weighing process, even if the measurement accuracy results of all the weighing hoppers 5 are good, they are outside the target weight range. Can easily grasp the abnormality of the operation cycle. In addition, since the measurement accuracy of the individual weighing hoppers 5 is determined based on the repeatability, it is possible to determine the signs of aging of each weighing hopper 5 and the replacement of parts by referring to the quality determination history during periodic inspections and the like. Can be easily performed.

  Further, the combination weighing device 1 of the second embodiment picks up an image with the measurement object detecting unit 21 when the master work conveyed in the weighing cycle under the same conditions as the product weighing is supplied from the trough 3 to the stock hopper 4. The article identification unit 22 collates the image data with the image identification information stored in the storage unit 14, and outputs a known weight of the master work indicating the identification result to the storage unit 14. Then, the weighing unit 11 measures the master work supplied to the weighing hopper 5 and outputs the measured value to the repeatability accuracy calculating unit 12b. The repeatability calculation means 12 b calculates the repeatability of the weighing hopper 5 to which the masterwork is supplied based on the measured value of the masterwork measured by the weighing unit 11 and the measurement number information stored in the storage unit 14. Then, whether or not the weighing hopper 5 selected based on the accuracy calculation value that is the calculation result (variation accuracy value or bias value) and the comparison value for quality determination stored in the storage unit 14 is measuring normally is determined. It is carried out.

  As a result, as in the first embodiment, since the weighing accuracy is measured in the weighing cycle under the same conditions as in the combination weighing process, the target weight of all the weighing hoppers 5 is assumed to be good despite the good measurement accuracy results. When it is out of range, it is possible to easily grasp abnormalities in various processing times in the operation cycle. In addition, since the measurement accuracy of the individual weighing hoppers 5 is determined based on the repeatability, it is possible to determine the signs of aging of each weighing hopper 5 and the replacement of parts by referring to the quality determination history during periodic inspections and the like. Can be easily performed.

  By the way, in the first embodiment described above, the opening / closing control is performed even when the weighing hopper 5 is empty (when there is no master work), but when the measured weighing value is equal to or greater than a predetermined value (when the weighing hopper 5 is not empty). However, it is determined whether or not there is a master work in the weighing hopper 5 by providing detection means for detecting the workpiece W supplied from the trough 3 to the stock hopper 4. You may do it. In this case, it is possible to detect an abnormality of the balance itself when the measurement value is less than a predetermined value despite the presence of the master work.

  Further, in the second embodiment described above, it may be determined whether or not there is a master work in the object detection unit 21. In this case as well, when the measurement value is less than the predetermined value despite the presence of the master work, it is possible to detect an abnormality in the balance itself. In addition, as a measurement accuracy determination of the weighing hopper 5 in the repeatability of the measured value, an accuracy calculation value obtained from the repeatability calculated by holding the measured value of the measured master work for the number of times of measurement and updated by the article identifying unit 22. The quality determination of the weighing hopper 5 is performed in comparison with the comparison value for quality determination, and the known weight of the master work identified by the article identification unit 22 and the measured value corresponding to the identified master work The difference may be held for the number of times of measurement, and the pass / fail judgment may be made by calculating the repeatability from the difference between the known weight of the master work and the measured value.

DESCRIPTION OF SYMBOLS 1 ... Combination measuring device 2 ... Dispersion supply part (2a ... Dispersion part)
3 ... Trough 4 ... Stock hopper 5 ... Weighing hopper 6 ... Collecting chute 7 ... Discharge hopper (7a ... Discharge door)
DESCRIPTION OF SYMBOLS 8 ... Conveyor 11 ... Weighing part 12 ... Calculation part (12a ... Combination calculation means, 12b ... Repeat accuracy calculation means)
13 ... Hopper control unit 14 ... Storage unit
DESCRIPTION OF SYMBOLS 15 ... Pass / fail judgment part 16 ... Input setting part 17 ... Display control part 18 ... Display part 20 ... Master work identification part 21 ... Weighing object detection part 22 ... Article identification part

Claims (4)

The objects to be weighed (W) having variations in individual weights are distributedly supplied to a plurality of hoppers, and the objects to be weighed supplied to the weighing hoppers (5) of each system are weighed in a predetermined measuring cycle set in advance. In the combination weighing device (1) for selecting the combination within the target weight range by combining the measured values obtained in this manner, and discharging the object to be weighed selected in the combination,
A measurement value obtained when a master workpiece of a known weight is measured by a weighing hopper operating in the weighing cycle is held for a preset number of measurements, and when the measurement number is reached, the weighing hopper to which the master workpiece is supplied A calculation unit (12) for calculating repetition accuracy;
Based on the accuracy calculation value based on the repetition accuracy calculated by the calculation unit and a predetermined quality determination value, it is determined whether the weighing hopper supplied with the master work is measuring normally or not. A determination unit (15);
A combination weighing device comprising: The weighing hopper (5) for calculating the repeatability by the master work, and an input setting section (16) for setting the weight of the master work,
2. The combination weighing apparatus according to claim 1, wherein the weighing hopper set by the input setting unit determines whether or not repeatability is good. A master work identification unit (20) for identifying a known weight of the master work supplied to each weighing hopper (5) of the plurality of systems;
The combination weighing device according to claim 1, wherein the quality determination unit (15) determines quality of repeatability based on the weight identified by the master work identification unit. A storage unit (15) for storing accuracy measurement detailed information including a quality determination result obtained by the quality determination unit (15) and a quality determination history based on the quality determination result;
A display control unit (18) for controlling the display of the accuracy measurement detailed information stored in the storage unit on the display unit (19);
The combination weighing device according to any one of claims 1 to 3, further comprising:

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