JP2022113358A - Number measurement device and method - Google Patents

Abstract

To perform accurate number estimation with a smaller number of times of measurement by considering variation in mass in measuring the number of measurement objects.SOLUTION: A number measurement device includes: means for receiving a total mass of a known number of articles to acquire a first measurement point composed of a set of the known number and the total mass; means for receiving the total mass at the time of adding an unknown number of articles, calculating the number of articles corresponding to the total mass at the time of adding the unknown number of articles by using a unit mass calculated from a set of the number acquired in the past and the total mass, and performing a step of acquiring the set of the number and the total mass n (n≥1) times to obtain n measuring points; means for acquiring a regression equation defining a relationship between the number and the total mass by using at least two measuring points composed of the first measurement point and the n measuring points; and means for further receiving the total mass at the time of adding the unknown number of articles, and calculating the number of articles by using the regression equation.SELECTED DRAWING: Figure 2

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a number-measuring device that calculates the number of articles (for example, screws) using an electronic balance using the mass output from the electronic balance.

A piece-measuring device measures the mass of a predetermined number of items using an electronic balance, calculates the mass of each item, and calculates the number of items by dividing the total mass of an unknown number of items. It has the function to FIG. 4 shows the basic configuration of the piece counting device. A plurality of articles are placed on the balance, the mass is measured, and the mass is sent to the arithmetic processing section via the mass receiving section. The arithmetic processing unit divides the mass by a predetermined number, calculates the mass of each single item, and registers it in the storage unit as the single mass. Subsequently, all the articles whose numbers are to be counted are placed on the balance, their masses are measured, and the masses are sent to the arithmetic processing section via the mass receiving section. The arithmetic processing unit divides the measured mass by the unit mass measured in advance to calculate the number and displays it on the display unit.

In the above-described number-measuring device, the mass of a single article is calculated by measuring the mass of the single article. Counting errors due to variability can be reduced by measuring the total quantity in small portions (for example, counting 200 quantities in 10 batches), but an increase in the number of weighings impairs the efficiency of piece counting. It will be. On the other hand, if you try to count more quantity in one measurement, the absolute value of the value obtained by multiplying the variation in the mass of the item (set based on the standard deviation) by the quantity of the item is the mass of the item itself. It is fraught with the problem of lack of counting accuracy when it becomes larger.

Several proposals have been made to consider variations in the mass of articles in counting numbers (Patent Documents 1 to 8), and many of them are based on measuring the mass of a single item multiple times. there is In a typical method, the average unit mass, which is the average of unit masses obtained a plurality of times, is regarded as the unit mass of the article, and the number of articles is counted. In addition, by measuring the basic mass a plurality of times, it is possible to calculate the variation in the mass of the articles, and it is possible to take the variation into consideration when counting the number of items.

For example, Patent Literature 2 describes calculating the average mass from the provisional average mass for each measurement, and calculating the variation coefficient of the sample mass from the variation in the provisional average mass and the average mass. In Patent Document 7, the unit mass of the sample is measured multiple times, the average unit mass and standard deviation of the sample are obtained, the maximum unit mass and minimum unit mass of the sample are estimated based on statistical calculation processing, and the counting error is Finding the maximum number of samples that do not occur is described.

In a piece-measuring device using a balance, variations in the mass of the items to be measured can cause an error in the number of pieces. end up
Japanese Patent Application Laid-Open No. 57-133321 Japanese Patent Application Laid-Open No. 58-171628 Japanese Patent Laid-Open No. 59-40122 Japanese Patent Laid-Open No. 60-31023 Japanese Patent Laid-Open No. 61-284616 Japanese Patent Laid-Open No. 1-94223 Japanese Patent Laid-Open No. 1-184419 Japanese Patent Laid-Open No. 4-60425 Japanese Patent Laid-Open No. 7-198467

An object of the present invention is to accurately estimate the number of objects with a smaller number of measurements by considering variations in mass from an approach different from the conventional one in counting the number of objects to be measured.

The technical means adopted by the present invention are:
means for receiving the total mass of a known number of articles to obtain a first measurement point consisting of a set of the known number and total mass;
Receive the total mass when adding an unknown number of items, and use the unit mass calculated from the set of the number and total mass obtained in the past, and the item corresponding to the total mass when adding the unknown number of items means for obtaining n measurement points by performing the step of calculating the number of and obtaining a set of the number and the total mass n (n≧1) times;
Means for obtaining a regression formula that defines the relationship between the number and the total mass using at least two measurement points consisting of a first measurement point and n measurement points;
Further, means for receiving the total mass when an unknown number of items are added and calculating the number of items using the regression equation;
An article counting device comprising:
The approach of the present invention is to obtain a regression equation defining the relationship between the number of articles and the total mass by performing a regression analysis using a plurality of points representing the relationship between the number of articles and the total mass, This regression formula is used to estimate the number of articles from the total mass of all articles.
Conceptually, one or more mass measurements plus the origin and performing a regression analysis, or two or more mass measurements plus the origin or no origin. Note that a regression line using only two points, the origin and the first measurement point, yields substantially the same results as using the average unit mass, including those that perform regression analysis.
The number estimation approach according to the present invention enables estimation that considers variance (inherent in each set of measurement points) by adopting estimation by regression analysis using a plurality of measurement points.

In one aspect, the means for acquiring the regression equation acquires the regression equation by adding the origin to the at least two measurement points.
In this aspect, by adding the origin to the measured mass and performing the regression analysis, it is possible to ensure weighing accuracy even with a smaller number of measurements.

In one aspect, the unit mass used in the means for acquiring the n measurement points is the unit mass calculated from the first set, the unit mass calculated from the previous set (total mass and total number), the past multiple is selected from the average unit mass of unit masses calculated from the set of
In the embodiment shown in FIG.
means for receiving the total mass of a known number of articles and obtaining a first measurement point (first total mass, first number) consisting of a set of the known number and total mass;
Receive the total mass when adding an unknown number of items, and use the unit mass calculated from the set of the number and total mass obtained in the past, and the item corresponding to the total mass when adding the unknown number of items Calculate the number of and execute the step of acquiring a set of the number and the total mass twice to acquire two measurement points (second total mass, second number; third total mass, third number) means to
means for obtaining a regression formula that defines the relationship between the number and the total mass using at least three measurement points (the origin may be added) consisting of the first measurement point and two measurement points;
Further, means for receiving the total mass (fourth total mass) when adding an unknown number of items and calculating the number of items using the regression equation;
An article counting device is disclosed, comprising:
The unit mass used in the means for acquiring the second measurement point is the unit mass calculated from the immediately preceding first set of first total mass and third number,
The unit mass used in the means for acquiring the third measurement point is the unit mass calculated from the second total mass and the second number of the immediately preceding second set.

In one aspect,
means for calculating the unit mass of the additional article for each measurement after the second measurement;
means for calculating the standard deviation of the unit mass for each measurement using the unit mass obtained in the first measurement and the unit mass of the additional article;
means for determining the accuracy of each measurement based on the standard deviation;
It has
That is, the counting device according to the present invention has a function of determining the accuracy of the counting amount by calculating the variation in the unit mass obtained from each measurement of a plurality of measurements and adding or subtracting the calculated variation. I have.
In one aspect, the pass/fail of the measurement is determined by setting a magnification (for example, 3 times) when adding or subtracting the calculated variation.

The present invention can be provided as a computer program for causing a computer to function as each means constituting the above apparatus.

The present invention
receiving the total mass of a known number of articles to obtain a first measurement point consisting of a set of the known number and total mass;
Receive the total mass when adding an unknown number of items, and use the unit mass calculated from the set of the number and total mass obtained in the past, and the item corresponding to the total mass when adding the unknown number of items a step of calculating the number of and obtaining a set of the number and the total mass n (n ≥ 1) times to obtain n measurement points;
obtaining a regression equation that defines the relationship between the number and the total mass using at least two measurement points consisting of a first measurement point and n measurement points;
a step of receiving the total mass when adding an unknown number of items and calculating the number of items using the regression equation;
It can be provided as a method for counting the number of articles consisting of.

In one aspect, the origin is added to the at least two measurement points to obtain a regression equation.
In one aspect, the unit mass used in the means for acquiring the n measurement points is the unit mass calculated from the first set, the unit mass calculated from the previous set, and the unit mass calculated from a plurality of previous sets. is selected from the average unit mass of

In the present invention, when estimating the number of objects to be measured, it is possible to accurately estimate the number with a smaller number of measurements by using a regression equation.

1 is a configuration diagram of a number-measuring device according to the present embodiment; FIG. 1 is a block diagram showing a number counting device according to this embodiment; FIG. It is a flow chart which shows the number counting method concerning this embodiment. 1 is a configuration diagram of a conventional number-measuring device; FIG.

As shown in FIG. 1, the number-measuring system according to this embodiment comprises an electronic balance and a number-measuring device. The piece counting device includes a mass receiving section that receives the mass measured by the electronic balance, an input section, an arithmetic processing section, a storage section, and a display section.

The number of times of weighing, the predetermined first weighing number, and the threshold coefficient are input from the input unit, and these information are stored in the storage unit. A predetermined number of measurement objects (articles) are placed on an electronic balance, and the total mass is measured. The total mass is input from the mass receiving section to the counting device and stored in the storage section. In the weighing after the second time, an arbitrary unknown number of articles are added, placed on the balance, and the total mass is measured repeatedly for the set number of times. The total mass obtained for each measurement is input from the mass receiving section to the counting device and stored in the storage section.

Based on the total mass for each measurement stored in the storage unit and the known number used in the first measurement, the arithmetic processing unit calculates the number for each measurement after the second time and the unit mass for each measurement. These information are stored in the storage unit. In the first measurement, the unit mass is calculated using the determined number, and in the second and subsequent measurements, the number is calculated using the unit mass calculated in the previous measurement (the first measurement if it is the second measurement), and stored. stored in the department. Further, the unit mass for each measurement is calculated by dividing the additional mass for each measurement by the added number and stored in the storage unit.

In the arithmetic processing unit, the origin is added to the mass and number measured each time, regression analysis is performed, and the regression equation (coefficient or slope, intercept) is stored in the storage unit. In addition, the mass standard deviation is calculated from the single mass of each time, multiplied by a threshold coefficient registered in advance, and stored in the storage unit.

All items are added to the balance, weighed, and sent to the processor via the mass receiver. From this mass, the number is calculated by a regression formula (coefficient or slope, intercept) registered in the storage unit, and the number is displayed on the display unit. The mass standard deviation registered in the storage unit is multiplied by this measured number, and if this value is greater than the individual mass at each time, there is a possibility that there is an error in the number measurement, so an alert is displayed on the display unit.

A piece counting device can be composed of a computer, and the computer is mainly composed of an input device for inputting data, an output device for outputting processed data, a display device for displaying data, and a CPU. Arithmetic unit, storage devices such as ROM, RAM, and hard disk, a bus connecting these devices, a predetermined program stored in the storage device for causing the computer to execute predetermined processing, and the like.

The piece counting device may be an integrated type in which a computer is incorporated in an electronic balance, or may be composed of a computer independent of the electronic balance. In the latter case, by preparing one piece counting device, the piece counting device can be selectively connected to a plurality of different electronic balances for use. Further, by providing the present invention as a number-measuring program and installing it in a general-purpose computer, the computer can be used as a number-measuring device.

The details of the article counting device according to the present embodiment will be described with reference to FIG. In FIG. 2, a predetermined number of articles are counted by four measurements, but the number of measurements is an example, and may be, for example, two or five.

In the first measurement, a known number of articles are placed on an electronic balance, the total mass of the known number of articles is measured as the first total mass, and the first set is obtained from the first total mass and the first number (known). is stored in the storage unit and set as the first measurement point (first total mass/first number). In the arithmetic processing section, the first unit mass related to the first measurement is calculated by dividing the first total mass by the first number and stored in the storage section.

In the second measurement, an unknown number of articles are additionally placed on the electronic balance, the total mass is measured as the second total mass, the second total mass is divided by the first unit mass, and the number of items in the second measurement is the second It is calculated as 2 pieces. A second set is acquired from the second total mass and the second number, stored in the storage unit, and set as a second measurement point (second total mass/second number).

In the arithmetic processing unit, the first total mass is subtracted from the second total mass to obtain the total mass of the articles added in the second measurement, and the first number is subtracted from the second number to obtain the articles added in the second measurement. , and divides the additional mass in the second measurement by the additional number to calculate the second unit mass related to the second measurement, and stores the second unit mass in the storage unit. Note that subtraction is omitted in FIG.

In the third measurement, an unknown number of articles are additionally placed on the electronic balance, the total mass is obtained as the third total mass, the third total mass is divided by the second unit mass, and the number of the third measurement is the third It is calculated as 3 pieces. A third set is acquired from the third total mass and the third number, stored in the storage unit, and set as the third measurement point (third total mass/third number).

In the arithmetic processing unit, the second total mass is subtracted from the third total mass to obtain the total mass of the articles added in the third measurement, and the second number is subtracted from the third number to obtain the articles added in the third measurement. is obtained, and the additional mass in the third measurement is divided by the additional number to calculate the third unit mass related to the third measurement, which is stored in the storage unit. Note that subtraction is omitted in FIG.

In this embodiment, the total mass of articles is measured twice or more, the origin is added to obtain a regression equation, and the final number of articles to be weighed is estimated by this regression equation. Adding the origin is optional and need not be used if enough measurement points are obtained to obtain a suitable regression equation. In the arithmetic processing unit, regression analysis is performed using four points obtained by adding the origin to the first measurement point, the second measurement point, and the third measurement point, and a regression equation is calculated. Coefficients or slopes and intercepts that define the regression equation are stored in the storage unit. In the fourth measurement, an unknown number of articles are additionally placed on the electronic balance, the total mass is obtained as the fourth total mass, and the fourth total mass and the regression equation are used to obtain the fourth number corresponding to the fourth total mass to estimate The fourth number is stored in the storage unit.

In the arithmetic processing unit, the total mass of the articles added in the fourth measurement is obtained by subtracting the third total mass from the fourth total mass, and the third number is subtracted from the fourth number to obtain the articles added in the fourth measurement. is acquired, and the total mass is divided by the number to calculate the fourth unit mass related to the fourth measurement, and the fourth unit mass is stored in the storage unit. Note that subtraction is omitted in FIG.

In the arithmetic processing section, the standard deviation is calculated using the unit mass for the number of measurements calculated for each measurement, ie, the first unit mass, the second unit mass, the third unit mass, and the fourth unit mass. In this embodiment, the variation is determined by multiplying the standard deviation by a scale factor (eg, 3 times). This variation is multiplied by the number of all measurement objects, and all the single masses (first unit mass, second unit mass, third unit mass, fourth unit mass) of all measurements are determined by the judgment formula (described later). If it satisfies the condition, it is satisfied that the total amount estimated using the regression equation is correct, and the number is displayed on the display unit. If any one or more unit masses do not satisfy the determination formula, the measurement is determined to be incorrect, and the measurer is notified by displaying the erroneous count on the display unit.

FIG. 3 is a flow chart illustrating a counting method according to the invention. A number counting flow according to the present embodiment will be described with reference to FIG.
(a) In step S1, a threshold coefficient (3 in this embodiment) used to determine the accuracy of the number is input. The threshold coefficient is stored in the storage unit.
(a) In step S2, input the number of times of weighing and the first number of weighings. The number of times of weighing and the number of weighed items are stored in the storage unit.
(c) In step S3, mass measurement is performed using a balance. Mass measurement is repeated the number of times defined in S2. For example, if the number of measurements is four, the first measurement, the second measurement, the third measurement, and the fourth measurement are performed, and the total mass for each measurement is acquired and stored in the storage unit.

(d) In step S4, the unit mass is calculated by dividing the first mass measurement value by the pre-input weighed number. For the second and subsequent measurement values, the number is calculated by dividing by the single mass immediately before (the first measurement if it is the second measurement). A regression equation (coefficient or slope, intercept) is calculated by performing regression analysis using a plurality of points obtained by adding the origin to all sets of measured mass values and numbers.

ここで、n：質量計測回数、x_i：i番目の単位質量、である。 Calculate the single mass by dividing each measured value by each number, and use the formula (1) to calculate the standard deviation.

Here, n: the number of mass measurements, and x _i : i-th unit mass.

ここで閾値はS6で算出した個数とS4で算出した質量標準偏差とS1で入力した閾値係数をかけ合わせて算出する。 (e) In step S5, measure the total mass of all objects to be measured. Next, in step S6, the number is calculated from the total mass using a regression equation.
(f) Calculate a threshold in step S7.

Here, the threshold is calculated by multiplying the number calculated in S6, the mass standard deviation calculated in S4, and the threshold coefficient input in S1.

(g) If the unit mass calculated in S4 each time satisfies the determination formula (2) on the condition that it is equal to or greater than the threshold value calculated in S7, the number is displayed as an accurate number in step S9. When the set number of times of weighing is four, the determination using the threshold value is applied to all of the second, third and fourth measurements.

(h) If one or more of the individual masses in each measurement is less than the threshold value, the number and NG are displayed on the display unit as accuracy is lacking, and the process returns to S3 to re-measure the total mass. Here, in order to prevent the unit mass from falling below the threshold value, it is necessary to reduce the number of total mass measurements and divide the total mass into multiple measurements. More precisely, we return to the second measurement. Reduce the number from the second time and measure again. Note that re-measurement may be repeated from any of the second, third, and fourth times. For example, if the unit mass in the second measurement satisfies the determination formula (2) and the unit mass in the third measurement does not satisfy the determination formula (2), return to the third measurement, the second measurement, If the unit mass in the third measurement satisfies the determination formula (2) and the unit mass in the fourth measurement does not satisfy the determination formula (2), the process may return to the fourth measurement.

Claims (8)

means for receiving the total mass of a known number of articles to obtain a first measurement point consisting of a set of the known number and total mass;
Receive the total mass when adding an unknown number of items, and use the unit mass calculated from the set of the number and total mass obtained in the past, and the item corresponding to the total mass when adding the unknown number of items means for obtaining n measurement points by performing the step of calculating the number of and obtaining a set of the number and the total mass n (n≧1) times;
Means for obtaining a regression formula that defines the relationship between the number and the total mass using at least two measurement points consisting of a first measurement point and n measurement points;
Further, means for receiving the total mass when an unknown number of items are added and calculating the number of items using the regression equation;
An article counting device consisting of: 2. The article counting device according to claim 1, wherein said means for acquiring said regression equation acquires said regression equation by adding an origin to said at least two measurement points. The unit mass used in the means for acquiring the n measurement points is the unit mass calculated from the first set, the unit mass calculated from the immediately preceding set, and the average unit mass of the unit masses calculated from a plurality of previous sets. selected,
A number-measuring device according to any one of claims 1 and 2. means for calculating the unit mass of the additional article for each measurement after the second measurement;
means for calculating the standard deviation of the unit mass for each measurement using the unit mass obtained in the first measurement and the unit mass of the additional article;
means for determining the accuracy of each measurement based on the standard deviation;
A piece counting device according to any one of claims 1 to 3, comprising: A computer program for causing a computer to function as each means according to any one of claims 1 to 4. receiving the total mass of a known number of articles to obtain a first measurement point consisting of a set of the known number and total mass;
Receive the total mass when adding an unknown number of items, and use the unit mass calculated from the set of the number and total mass obtained in the past, and the item corresponding to the total mass when adding the unknown number of items a step of calculating the number of and obtaining a set of the number and the total mass n (n ≥ 1) times to obtain n measurement points;
obtaining a regression equation that defines the relationship between the number and the total mass using at least two measurement points consisting of a first measurement point and n measurement points;
a step of receiving the total mass when adding an unknown number of items and calculating the number of items using the regression equation;
A method for counting the number of articles consisting of. 7. The article counting method according to claim 6, wherein a regression equation is obtained by adding an origin to the at least two measurement points. The unit mass is selected from the unit mass calculated from the first set, the unit mass calculated from the immediately preceding set, and the average unit mass calculated from a plurality of past sets.
The number counting method according to any one of claims 6 and 7.

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