JPH04207B2 - - Google Patents

Description

[Detailed Description of the Invention] This invention provides a method for calculating the number of parts, products, merchandise, etc. (hereinafter simply referred to as single units) whose unit weight varies.
The present invention relates to a counting device for accurately counting based on weight measurement.

In the production process and product distribution process in factories, etc.,
There are many processes that involve supplying or storing a fixed number of single units with the same shape. At this time, it is necessary to accurately count and manage the supplied and stored units, and conventionally, the passing of the units is detected one by one by a sensor, and the number of units is directly counted. however,
It takes time to accurately separate individual substances one by one, it is difficult to count quickly, and the single separation equipment is large and requires a lot of space.
It had drawbacks such as not being suitable for actual situations due to the limited layout space.

In addition, instead of directly counting the number of individual units as in the past, we can measure the total weight of a set of supplied and stored units (for example, one case) at once, and divide that weight by the reference weight of one unit. There is also a counting device that calculates the number of objects. However, there was a fatal drawback in that the unit weight of a single item itself fluctuated, and as a result, as the number of weighed items increased, errors would accumulate, resulting in counting errors.

This invention was made in view of the above-mentioned circumstances, and it can be used even for a single unit whose unit weight fluctuates.
The object of the present invention is to provide a single counting device that can quickly and accurately count the number of objects.

This invention will be explained below.

This invention relates to a unit counting device, and relates to a weighing scale for measuring the weight of a plurality of units, an average weight A of the units, and a maximum variation range α of the weight per unit.
and data input means for inputting the maximum weighing error β of the scale, the weight value from the scale and each data from the data input means, and dividing the above weight value by the average weight A to obtain the number N. , N<
It is provided with an arithmetic processing means for determining whether or not (A/2-β)/α is satisfied and outputting a counting result.

First, the principle of this invention will be explained.

The average weight of each unit with fluctuation in unit weight is A, the maximum variation range of the weight per unit is ±α,
The maximum measurement error of a weighing scale that measures the weight of a single item is ±
Assuming that β, the total weight W of a single unit of N pieces is within the range of W=N×(A±α)±β =NA±(Nα+β) (1) using the above weighing scale. When calculating the number of pieces by dividing the weighing value of the scale by the average weight A of the unit, if the number of pieces is obtained by rounding off the fraction of the divided value, the cumulative error ± ( It is necessary that the absolute value (Nα+β) of Nα+β) is smaller than 1/2 of the average weight A of the single unit.
That is, Nα+β<A/2...(2), and if this equation (2) is transformed, N<(A/2-β)/α...(3). As a result, the maximum permissible supply number M of single units without any counting error becomes the largest integer value among the numerical values N that satisfy the above equation (3). This invention takes the maximum allowable supply number M determined as described above as a theoretical cornerstone. That is,
In this invention, when supplying a certain number of single units and storing them in a case, etc., instead of measuring the total weight after completing the supply of the entire number of single units, all the single units are divided into multiple supplies and supplied. , the weight of the feeding process is measured sequentially. Then, the weight of each divided supply is determined, and this weight value is divided by the average weight A of the single unit to convert it into the number of units. In this case, if the number of units to be dividedly supplied is always managed to be within the allowable maximum supply number M, a counting error will not occur even when the number is converted from the weight. By repeating such divisional supply of single units and accumulating error-free count values, there will be no total counting error even when the entire quantity of single units is finally supplied.

FIG. 1 is a block diagram showing an embodiment of the present invention, in which a unit 1 whose weight fluctuates is housed in a main hopper 2 and a small sub-hopper 3 disposed near the main hopper 2. The single pieces 1 housed in the sub hopper 2 are discharged from the discharge pipe 2A to the single piece conveying device 10 via the single piece supply valve 4, and the single pieces 1 housed in the sub hopper 3 are discharged through the single piece cutting device 5. Similarly, the pieces are discharged one by one from the discharge pipe 3A to the single unit conveyance device 10. Single unit conveyance device 1
0 constitutes a conveyor with a pair of rollers 12 and 13 and a belt 11 wound around these rollers 12 and 13, and a motor 14 moves the single body released and placed on the belt 11 in the storing direction Q or the collecting direction P. The single conveyance device 10
The weight of the unit released and placed on the belt 11 is detected by a weight detector 15 that is integrally constructed with the unit conveyance device 10. In addition, a storage case RC for storing the single unit is installed in the storage section of the unit transport device 10, and a collection hopper 6 is disposed in the collection unit, and the collection hopper 6 discharges the unit. The collected single pieces are collected into the main hopper 2 from a collection pipe 8 via a collection blower 7. Furthermore, the weight signal WS from the weight detector 15 is input to the arithmetic processing/control means 20, and the data DT input from a data input device 28 such as a keyboard is also input to the arithmetic processing/control means 20. The motor 14 is controlled to reversibly rotate and stop by the drive signal DS output from the means, and the single supply valve 4 is controlled by the single supply signal SP,
The unit cutting device 5 of the sub-hopper 3 is configured to cut out each unit one by one in accordance with a cutting signal CT. Further, the display signal DP from the arithmetic processing/control means 20 is input to the display device 30, so that a manager, operator, etc. can check the unit count.

Here, the arithmetic processing/control means 20 receives the weight signal WS from the weight detector 15 and the data input device 28.
an input circuit 23 serving as an interface for inputting data DT from the input circuit 23; a counting condition determination control circuit 22 that receives signals from the input circuit 23 and performs counting processing, and also determines and controls various conditions to be described later; A cumulative correction control circuit 24 that corrects the average weight A from the cumulative weight value and the corresponding cumulative count value, and a floating circuit that corrects the average weight A from the cumulative weight value of a certain section and the corresponding cumulative count value. The average correction control circuit 26, the maximum fluctuation range calculation circuit 27 that performs the correction calculation of the maximum fluctuation range α, and the correction processing by the counting condition judgment control circuit 22 are switched between the cumulative correction control circuit 24 and the floating average correction control circuit 26. It is composed of a correction switching circuit 25, an output circuit 21 as an interface that outputs the data output by the counting condition judgment control circuit 22 to each part, and a counting condition judgment control circuit 22, a cumulative correction control circuit 24, and a correction switching circuit. The circuit 5, the floating average correction control circuit 26, and the maximum variation range calculation circuit 27 are interconnected, and can be constructed from a computer system such as a microprocessor.
The display device 30 also includes a divided measurement number display 33 that displays the number of divided measurements when dividing and weighing a single unit.
, an allowable maximum supply quantity indicator 31 that displays excess or deficiency with respect to the allowable maximum supply quantity M, and a cumulative weighed quantity display 34 that displays the cumulative value of the weighed individual items.
and a target measured quantity excess/deficiency indicator 32 that displays excess or deficiency with respect to the target measured quantity of a single unit, and each of the indicators 31 to 34 is made of a light emitting diode, a liquid crystal, or the like.

In such a configuration, the average weight of a single unit with weight fluctuation is A, the maximum variation width of the unit is α, the maximum weighing error of the weight detector 15 is β, and a total of Z units 1 are accurately counted. The operation when storing in the storage case RC will be explained with reference to the drawings of FIG. 2 and FIGS. 3A to 3J.

First, the single body 1 to be weighed is supplied to the main hopper 2 and the sub hopper 3, and an empty storage case RC is placed at one end of the single body conveying device 10 as shown in the figure. Then, the data input device 28 inputs the average weight A, maximum fluctuation range α, and maximum weighing error β, which have been determined in advance, as well as the value of the target weighing number Z, and then inputs the counting conditions via the input circuit 23. It is input to the determination control circuit 22. The counting condition judgment control circuit 22 calculates a value determined by the formula (A/2-β)/α from the average weight A, the maximum fluctuation range α, and the maximum weighing error β, and calculates the allowable value, which is the maximum integer value less than this value. The maximum supply quantity M is determined and stored in the memory, and the input target measured quantity Z is also stored in the memory. After that, the counting condition judgment control circuit 22 clears the divided weighing display 33 and the cumulative weighing number display 34 via the output circuit 21, and sets the display on the allowable maximum supply number excess/deficiency display 31 to "-M". At the same time, the display on the target measurement quantity excess/deficiency indicator 32 is set to "-Z" (see FIG. 3A). Note that the symbol "-" on the displays 31 to 34 indicates a shortage, and the symbol "+" indicates an excess. When there is no excess or deficiency, "0" is displayed.

Next, the counting condition determination control circuit 22 outputs the output circuit 2.
1 to output a single unit supply signal SP to open the single unit supply valve 4, and transfer the single unit 1 housed in the main hopper 2 from the discharge pipe 2A onto the belt 11 of the single unit conveying device 10 as shown in FIG. Place it like this. In this case, the weight detector 15 is
It is now possible to purely measure the weight of a single unit 1A using 0 as a tare, and the unit 1 that has been discharged and placed
The weight of A is continuously input to the counting condition determination control circuit 22 via the input circuit 23 as a weight signal WS. The counting condition judgment control circuit 22 sequentially divides the gradually increasing weight of the single body 1A by the average weight A to convert it into the number of single bodies 1A, and when the number of single bodies on the belt 11 approaches the maximum allowable supply number M, the single body is supplied. Close valve 4. Then, the counting condition determination control circuit 2
2 obtains an accurate weight value when the weight signal WS from the weight detector 15 becomes stable, and inputs it to the data input device 2.
The number N1 to be supplied is determined by dividing by the average weight A of the individual pieces input from 8. At this time, the display on the allowable maximum supply quantity indicator 31 is updated to "N1-M" as shown in FIG. 3B, and the display on the divided weighing quantity display 33 is also updated to "N1". .
Then, if N1≦M, no counting error occurs, so the counting condition judgment control circuit 22 outputs the output circuit 21.
A drive signal DS is applied to the motor 14 through the motor 14 to drive the belt 11 of the single unit conveying device 10 in the Q direction to eject and store the single unit 1A into the storage case RC as shown in FIG. 2 as shown in 1B. At this time, the display of the allowable maximum supply quantity excess/deficiency indicator 31 is "-M", and the display of the target measured quantity excess/deficiency indicator 32 is "N1-Z".
Then, the display on the divided measurement number display 33 is updated to "0" and the display on the cumulative measurement number display 34 is updated to "N1" (see FIG. 3C). If the correction switching circuit 25 specifies the floating average correction control circuit 26, the current unit weight WS is divided by the number N1 to obtain the average weight A', and this value is used as the new unit weight A'. Correct as follows.

On the other hand, if N>M, there is a possibility that a counting error has occurred, so the counting condition determination control circuit 22 outputs the drive signal DS for collection via the output circuit 21.
is applied to the motor 14 to drive the belt 11 of the unit conveyance device 10 at low speed in the P direction, and gradually release the unit 1A placed on the belt 11 into the recovery hopper 6 (unit 1C). The single unit 1C is transferred from the recovery pipe 8 to the main hopper 2 via the recovery blower.
At the same time, the counting condition determination control circuit 22 collects the weight of the single unit 1A, which gradually decreases, to the weight detector 15.
Continuously detects weight signal WS from At this time, the weight signal WS is successively divided by the average weight A to convert it into the number of single pieces 1A, and when the number of single pieces on the belt 11 becomes smaller than the allowable maximum supply number M, the drive of the motor 14 is stopped. The counting condition determination control circuit 22 obtains an accurate weight value when the weight signal WS from the weight detector 15 becomes stable, and divides the weight value by the average weight A to obtain the number N1'. At this time, the display device 30 becomes as shown in FIG. 3D, and the number of
If N1' is less than or equal to the maximum allowable supply number M, the above-described storage operation to the storage case RC is performed, and if the number N1' is greater than the allowable maximum supply number M, the above-mentioned collection operation to the collection hopper 6 is repeated. .

Furthermore, by repeating the same weighing operation for the single body 1 as described above, the single body 1 is weighed and the number of pieces is converted. In this case, if the number of pieces supplied from the main hopper 2 of the unit 1 is N2, the display on the allowable maximum supply number excess/deficiency indicator 31 will be "N2-M" as shown in FIG. The display will be updated to “N2”. If the number of supplied pieces N2 is the maximum allowable number of supplied pieces M, the single pieces 1 released onto the belt 11 are
Store A in storage case RC. The display state of the display device 30 in this case is as shown in FIG. 3F. In addition, if the supplied number N2 is larger than the allowable maximum supplied number M, perform the same collection operation as described above to collect a part of the unit 1A, weigh it again, and count the number of pieces.
Since N2' is determined, the display becomes as shown in FIG. 3G.

By repeating the storage/recovery operation as described above several times, the cumulative measured number gradually approaches the target measured number Z. Figure 3 H is after the target measurement number Z
Indicates that there is a shortage of items.

In this way, when the number of single pieces is insufficient to the target weighing number Z by Y pieces, the counting condition determination control circuit 22 outputs a cutting signal CT to the single piece cutting device 5 via the output circuit 21. As a result, the unit cutting device 5 cuts out the units 1 one by one from the sub-hopper 3 and discharges them. Therefore, by applying the cutting signal CT to the cutting device 5 Y times, a total of Y single pieces 1 are discharged and supplied onto the belt 11 from the sub-hopper 3 via the discharge pipe 3A. Become. In addition, since the discharge of the single body 1 by the single body cutting device is generally much slower than the discharge by the single body supply valve 4,
Use only for final small number adjustment. The number Y at this time satisfies Y<M, and is preferably as small as possible. To be on the safe side, release pipe 3
A or the like may be provided with a discharge number detector using a photoelectric sensor or the like to count the number of discharged particles. In this case, the display on the display device 30 will be as shown in FIG. 3I.
Then, when the last Y units are also stored in the storage case RC and the target measurement number Z of units 1 is completed, the display becomes as shown in FIG. 3J.

In this way, the number of parts to be weighed each time is always managed to be less than the maximum allowable supply number M, and in a managed state, the number of pieces to be weighed separately is 1.
Since the measurement is repeated, the single unit 1 is measured without any counting error.
The total quantity of can be found. Then, when the correction switching circuit 25 specifies the cumulative correction control circuit 24, the cumulative weight of Z individual pieces is divided by the number Z to obtain an average weight A', and this value is corrected as a new average weight A. . In this way, the storage case RC that has accurately stored the target weighing number of Z units 1 is transported to the next process, and then the empty storage case that has been transported to the storage section is stored in the single-to-one storage case described above.・
By repeating the collection operation, it is possible to sequentially count and store Z single units very accurately and transport the storage case RC to the next process.

On the other hand, in order to correct the maximum variation range α of the weight of the individual objects 1, as shown in FIG. Each time a single unit is supplied, the weight is measured, and 1 is calculated based on the increase in weight.
The weight of each piece is determined and the data is sequentially stored in the maximum fluctuation range calculation circuit 27. Then, the maximum weight per single item is determined from the multiple stored weighing data groups.
Find A _nax and the minimum weight A _nio , find the maximum fluctuation range α′ as α′ = (A _nax − A _nio )/2 …(4), and correct this α′ as the new maximum fluctuation range α. .

In addition, the weight detector 15 in the above-mentioned embodiment can be configured with a load cell, a differential transformer, an encoder, etc., and the display device 30 may be replaced with a printing device, an audio output device, or other output device, or It is good to have a configuration in which these are juxtaposed. In addition, when the allowable maximum supply number M is exceeded, the removal of the single unit can be performed by using a device such as a scraper, a gripper, or a vacuum suction device, in addition to the conveyor driven by the belt 11 of the unit conveying device 10. Corrections may be made for each divided supply range, or
It is also possible to accumulate a certain number of measurements and delete old data one by one. Further, when correcting the maximum variation range α of the unit weight, instead of supplying it from the unit cutting device 5, it may be possible to manually weigh one unit and input it from the data input device.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, FIG. 2 is a configuration diagram for explaining an example of its operation, and FIG.
Figures A to J are diagrams for explaining operation examples of the present invention according to display examples of a display device, respectively, and Fig. 4 is a configuration diagram showing an operation example of the present invention. 1,1A~1C...Single unit, 2...Main hopper, 2A...Discharge pipe, 3...Sub hopper, 3
A...Discharge pipe, 4...Single supply valve, 5...Single cutting device, 6...Recovery hopper, 7...Recovery blower, 8...Recovery pipe, 10...Single transfer device,
11... Belt, 12, 13... Roller, 14...
... Motor, 15 ... Weight detector, 20 ... Arithmetic processing/control means, 21 ... Output circuit, 22 ... Counting condition judgment control circuit, 23 ... Input circuit, 24 ...
Cumulative correction control circuit, 25... Correction switching circuit, 26
... Floating average correction control circuit, 27 ... Maximum fluctuation range calculation circuit, 28 ... Data input device, 30 ... Display device, 31 ... Maximum supply quantity excess/deficiency indicator, 32 ... Target measurement number excess Insufficient indicator, 33...
Divided measurement number display, 34... Cumulative measurement number display.

Claims (1)

[Scope of Claims] 1. A main hopper for accommodating a single unit, and a main hopper that measures the weight of the single unit discharged from the hopper and placed on a conveyor, and transports the placed unit by the conveyor into a storage case. Alternatively, a weight scale for transporting to the recovery hopper, a collection means for recovering the recovery unit released into the recovery hopper to the main hopper, an average weight A of the unit, and a maximum variation range α of the weight per unit. and a data input means for inputting the maximum weighing error β of the weighing scale, and inputting each data from the weight value from the weighing scale and the data input means, and inputting the weight value of the placed single unit into the average weight A. Find the number N by dividing by N<
The maximum allowable supply number M of the maximum integer satisfying (A/2-β)/α is determined, and the conveyor is driven to store the placed units in the storage case, and the number N is ( A/2-β)/α or more, an arithmetic processing/control means configured to drive the conveyor to discharge the placed unit to the collection hopper, and a data input means. 1. A single counting device comprising: a display device for displaying each input data and the results of arithmetic processing by the arithmetic processing/control means. 2. Counting of single units according to claim 1, wherein a sub-hopper for housing single units equipped with a single unit cutting device whose release amount is controlled by the calculation processing/control means is arranged in parallel with the main hopper. Device. 3. The arithmetic processing/control means includes an input circuit for inputting data, a counting condition determination control circuit for performing necessary counting processing and condition determination based on the input data from the input circuit, and a counting condition determination control circuit for determining the cumulative value of the weight values. a cumulative correction control circuit for correcting the average weight A, a floating average correction control circuit for correcting the average weight A, and a maximum fluctuation range calculation circuit for performing correction calculation for the maximum fluctuation range α;
and an output circuit that outputs the processing result of the counting condition determination control circuit.
A single counting device as described in Section. 4. The display device includes a divided measurement number display that displays the number of divisions to be measured when dividing and weighing the unit, and a maximum allowable supply number excess/deficiency indicator that displays excess or deficiency with respect to the allowable maximum supply number M. , a cumulative measurement number display that displays the cumulative value of each weighed unit;
2. The unit counting device according to claim 1, further comprising a target measurement number excess/deficiency indicator that displays an excess or deficiency with respect to the target measurement number of the unit.