JPH0652189B2 - Counting scale - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a counting scale for determining the number of identical articles such as electronic articles, mechanical parts, and office articles from their weights.

<Prior Art> In a counting scale, generally, the unit weight value (average weight) of a known number of articles is obtained, and the weight of an unknown number of articles is divided by the unit weight value to obtain the number.

By the way, according to such a counting method, a counting error occurs depending on the variation in the weight of the article, and the magnitude of the error is also related to the number to be counted at one time.

Therefore, when weighing a certain target number, the article is placed on the weight detection unit several times until the displayed value reaches the target number. The final counting error will change depending on the number.

In a conventional counting scale, such an error is ignored, or the maximum countable number L ₀ at which a counting error does not occur at a certain probability or more is obtained in advance, and the countable number L ₀ or less is calculated. Some have taken measures to put them all at once.

<Problems to be Solved by the Invention> Regarding conventional counting scales that ignore errors, the counting results are naturally unreliable, and the maximum number L ₀ or less that can be counted without error is placed. Then, the efficiency of counting work is poor.

In the weighing operation of the target number, the maximum allowable counting error (or average allowable error) is often given to the weighing number, and in the present invention, in such a case, the error is within the allowable maximum counting error. Realize a counting scale that can perform counting work efficiently while guaranteeing that it is within the range.

<Means for Solving the Problems> In the present invention, as shown in the basic conceptual diagram of FIG. 1, the weight value W measured by the weight detection unit a is divided by the unit weight value μ of the article, and In the balance equipped with the number calculation means b for calculating the number, the number n of samples used for calculating the unit weight value μ
Setting means c and setting means d for the coefficient of variation ε of the article to be counted
The target number N to be counted and the input means e for inputting the allowable maximum counting error E for the target number N, the coefficient of variation ε, the sample number n, and the number calculation result k by the number calculating means b are used in advance. The counting error calculating means f for calculating the maximum counting error I included in the number k with a given probability or more, the comparing means g for comparing k and n, and I and E, respectively, and the comparison result On the basis of K> N or I> E (1), a notification means h is provided to notify that fact, and when the comparison result is k ≦ N and I ≦ E (2) Is configured such that the next target number is set to Nk and the next allowable maximum counting error is set to E-I so that counting can be continued.

The sample number setting means c and the variation coefficient setting means d in the present specification are means for inputting the sample number n or the variation coefficient ε from the outside, respectively, or the balance itself calculates the unit weight value. It may be a function of obtaining and storing the sample number n or the coefficient of variation ε of the article to be counted in the process.

<Operation and Principle of the Invention> The number n of samples used for obtaining the unit weight μ of the article,
If the coefficient of variation ε of the article is known, the maximum counting error I included in the number k counted at one time can be calculated with a probability P or more given in advance.

That is, the probability that the counting error becomes 0 from n, ε, and k
p _0, also the j (j is an arbitrary integer) is calculated to become probabilities p _i, p ₀ or (Where I is a positive integer) does not become smaller than a given probability P
Is obtained, this I becomes the maximum counting error included in k.

That is, if p ₀ ≧ P, then I = 0, and if not, The smallest i that satisfies is I.

In this way, the maximum error I that can be stochastically expected to occur for each count is obtained, and this I, the maximum allowable count error E previously input, and the target number N and the current count result k are obtained. , And when (2) is satisfied, the next target number and the maximum allowable counting error are Nk
Similarly, the following counting operation is possible as EI and EI, and in the case of (1), the fact that the article is overloaded is notified by notifying the operator that the final counting error is EI. It is guaranteed that the number is within the range, and the number of pieces to be counted at one time can be increased as much as possible within the allowable counting error.

<Embodiment> FIG. 2 is a block diagram showing a configuration of an embodiment of the present invention.

The weight detection unit 1 includes a load sensor that engages with the dish 1a and A-
It has a built-in D converter and the like, and can output digital data corresponding to the load on the plate 1a.

The data from the weight detection unit 1 is stored in the CPU 21, the ROM 22.
And is incorporated into the microcomputer 2 including the RAM 23 and the like.

The microcomputer 2 has a display 3 for digitally displaying the counting result, a light emitting diode 4 for notifying an operator of the excessive loading of articles on the dish 1a, a target number N and an allowance as will be described later. A keyboard mainly composed of a numeric keypad for inputting the maximum counting error E, the unit weight value μ of the article to be counted, the sample number n used for calculating the unit weight value μ, the coefficient of variation ε of the article to be counted, and the like. 5 is connected, and an input / output port 6 for connecting to an external device such as a printer or a personal computer is provided.

A program to be described later is written in the ROM 22 of the microcomputer 2 and a RAM
Reference numeral 23 denotes a work area and an area for storing the above-mentioned various input data from the keyboard 5, and a maximum number sequence {L _{i that} can be counted by a counting error i, which will be described later, calculated by inputting this data. } (I = 0,1,2,3 ...) is set in the area.

FIG. 3 is a flow chart showing the contents of the program written in the ROM 22. Hereinafter, the operation of the embodiment of the present invention will be described together with the method of use with reference to this figure.

Prior to the counting operation, the unit weight value μ of the item to be counted, the sample number n used for calculating the unit weight value μ, the coefficient of variation ε of the item to be counted, the target number N to be counted, and the target number N thereof. The maximum permissible counting error E for is input using the keyboard 5.

Note that this input may be data transferred from, for example, a personal computer connected to the input / output port 6.

Then, when such various kinds of data are input, using the number of samples n and the coefficient of variation ε among them, it is possible to count within a counting error i with a probability P that is sufficiently close to 1 given in advance. A sequence {L _i } (i = 0,1,2,3, ...) Of the maximum number L _i
...) is calculated and the sequence thereof is stored in the RAM 23.

The method of obtaining the sequence {L _i } is as follows.

From the normal distribution table, Β ₀ is obtained.

In this case, with a probability P or more, counting error maximum number that can be counted on within _i L i is, Is obtained as the maximum integer k that satisfies

That is, Becomes In addition, [] is a Gaussian symbol, and means the maximum integer that does not exceed the internal numerical value.

This sequence {L _i } is 0 <L ₀ <L ₁ <L ₂ <... <L _i <... For example, if the result of counting an arbitrary number of k samples is k, then L _i I _{0 such} that ₋₁ <k ≦ L _i0 (6) is uniquely determined. In this case, the counting error is i
_The probability of being ₀ or less can be said to be P or more (not that the counting error is i ₀ ).

Now, when the article to be counted is placed on the dish 1a after obtaining such a sequence {L _i }, the weight increase on the dish 1a based on the data from the weight detection unit 1 is performed as in a normal counting scale. W is calculated, and then the weight W is divided by the unit weight value μ in the RAM 23 and rounded to calculate the number k of articles.

Then, the number k is compared with the target number N, and when k exceeds N, the light emitting diode 4 is turned on to notify that effect. If k is equal to or less than N, the process proceeds to the next step, and from the number k and the sequence {L _i }, the number k is equal to or more than the probability P.
The maximum counting error I (corresponding to i ₀ in the above equation (6)) included in is calculated.

Next, this I is compared with the maximum allowable counting error E, and I is E
If it exceeds the limit, the light emitting diode 4 is turned on to inform the operator that it is overloaded.

If I is equal to or less than E, the target number is set to Nk and the maximum allowable counting error is also set to E-I, and the next article addition is waited for.

According to the embodiment of the present invention, an operator freely places an arbitrary number of articles on the dish 1a from the beginning of counting, and only when the light emitting diode 4 is turned on, it is considered that the article is overloaded. If the article is unloaded and the counting operation is stopped when the displayed value matches the target value N, it is guaranteed that the error included in the obtained counting result is within the allowable maximum counting error E.

In other words, the fact that I exceeds E due to the addition of several items means that the sum of all I has exceeded the maximum allowable counting error E originally given until then. It means that the error contained in the present count display value may not exceed the maximum allowable count error E, and the light emitting diode 4 is turned on only in this case. Therefore, as long as the light emitting diode 4 is not turned on, it is guaranteed that the final counting result includes only the error within the allowable maximum counting error E, regardless of the number of plates placed on the plate 1a at one time. .

Therefore, the operator can place any number of samples without worrying about how many samples must be placed,
When the light emitting diode 4 is turned on, all that is necessary is to lower the sample until the light is turned off. In this way, the work can be continued until the displayed value matches N.

As a means for notifying the excessive loading, in addition to lighting the above-mentioned lamps such as the light emitting diode, sounding of a buzzer or blinking of the count display value can be performed.

The number displayed on the display 3 is the total number,
When notifying the overloading, for example, "Sub x"
Alternatively, the display may be switched to "Over x" or the like. Further, such an indicator can be provided together with the total indicator.

By the way, the aforesaid prior information of the maximum number L _i that can be counted within the counting error i is analyzed in more detail, and the probability that ₀ counting errors occur q ₀ +1 〃 q ₁ -1 〃 q _-1・ ・ ＋ i 〃 q _i −i 〃 q _-i is obtained (usually due to symmetry, q _-i = q _i ), e _i = 0 ・ q ₀ +1 ・ (q ₁ + q _-1 ). + ... + i · (q _i + q ₋₁ ) = 2Σjq _j ··· is obtained as the average counting error e _i instead of the maximum counting error i. Then, if E-e _i0 is used instead of E-I and the same operation as in the above-described embodiment is performed, the efficiency is further improved.

Alternatively, since the counting error can be large due to the efficiency, the two parties are mixed and the number of times of using e _i0 is limited in advance to, for example, 3 times,
From the fourth time, a method of using i ₀ can be adopted.

This may be further improved to limit the number of times e _i0 is used only when the value of e _i exceeds a certain value (for example, 0.5).

Note that the normal expected value 0 · q ₀ + 1 · q ₁ + ( _-1 ) · q ₋₁ + ・ ・ ・ i ・ q _i + ( _-i ) ・ q _-i・ ・ ・If you ask for (7), it will be 0, so it will be useless.

Further, in each of the above embodiments, for safety, the target number N may be corrected to N + E and N + E may be counted.

Further, even if the maximum allowable counting error E is not input, the above-described operation may be automatically performed with a fixed number, for example E = 5.

In the determination of E, the number is not always the same, but according to the target number N, N ≦ 1000 ... E = 5 1000 <N ≦ 10000 ... E = 10, etc. You may make it decided based on the rule of.

The number n of samples used for the calculation of the unit weight value is set particularly when the balance is of a type that automatically calculates by placing a predetermined fixed number on the counting scale. No need. Further, the coefficient of variation ε also needs to be input from the outside especially if the balance has a function of automatically calculating it in the process of calculating the unit weight, for example, by putting one on the counting scale. Nor.

<Effects of the Invention> As described above, according to the present invention, even if the counting work is performed without paying too much attention to the number of pieces to be placed at one time, the final counting result can be obtained until the overload is notified. Is guaranteed to include only errors within the bounds of the counting error specified to be allowed in advance.

On the contrary, it is possible for the operator to set the allowable maximum counting error such as 1, 2, ..., And to have an idea of what the allowable counting error is the one that is most easy to use. This allows the operator to decide whether to count more carefully or at this pace.

[Brief description of drawings]

FIG. 1 is a basic conceptual diagram showing the configuration of the present invention, FIG. 2 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 3 is its ROM.
22 is a flowchart showing the contents of the program written in 22. 1 ... Weight detection unit 2 ... Microcomputer 21 ... CPU 22 ... ROM 23 ... RAM 3 ... Display 4 ... Light emitting diode 5 ... Keyboard

Claims (1)

[Claims] 1. A sample used for the calculation of the above-mentioned unit weight value in a balance equipped with a number calculation means for dividing the weight value measured by the weight detection unit by the unit weight value of the item to calculate the number of the item. A means for setting the number n, a means for setting the coefficient of variation ε of the article to be counted, an input means for inputting the target number N to be counted and an allowable maximum counting error E for the target number N, the coefficient of variation ε, the sample Using the number n and the number calculation result k by the number calculation means, a counting error calculation means for calculating the maximum counting error I included in the number k with a probability higher than a predetermined probability; And comparing means for respectively comparing I and E and k> N based on the comparison result, or notification means for notifying that if I> E, and the comparison result is k ≦ N, and Where I ≤ E Counting, characterized in that it is configured for the next target number N-k, to allow continued counting the next maximum allowable counting error as E-I scale to.