JPH0158451B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to the combination counting of items whose individual weights (hereinafter referred to as unit weights) vary slightly, such as bolts, nuts, cups filled with milk, etc. , relates to a more accurate method of counting items.

Conventionally, a large number of items are divided into multiple weighing machines with appropriate variations, and the number of items is calculated by dividing the weight of the item obtained by each weighing machine by the unit weight of the item. There is a combination counting method in which combinations are calculated to find a combination that is equal to or closest to a set number of items, and items are discharged from a weighing machine that corresponds to the combination. In this case, if there is an error in the unit weight, an error will also occur in the calculated number of pieces for each weighing machine, and of course there will also be an error in the combined number obtained by combining the numbers. This will result in inaccurate counting. Also,
The larger the number of items weighed by one weighing machine, the larger the error in the calculated number of items. Therefore, in order to accurately calculate the number of items, it is necessary to accurately determine the unit weight. However, as mentioned above, there are variations in products, so it is pointless to accurately weigh a single product to determine the unit weight. It is better to find the unit weight by dividing, and the more items you weigh, the more accurately you can find the unit weight.

Furthermore, when combination counting is repeated, the overall unit weight of the items may gradually decrease (increase) over time. This occurs, for example, when filling a cup with milk, because the viscosity of the milk fluctuates due to changes in the ambient temperature.

Therefore, it is better to update the unit weight of the item, which is numerically set by an appropriate means at the start of weighing, one after another using the unit weight obtained by calculating each weighing.

Therefore, in order to achieve this objective, the applicant weighs a large number of items using multiple weighing machines, and calculates the number of items in each weighing machine by dividing the weight measured by each weighing machine by the unit weight. Then, calculate the number of combinations by calculating the combination of each number, find one combination in which the number of combinations is equal to or closest to the set number, and calculate the weight of any one or more weighing machines and the number of pieces mentioned above. We have invented a system that calculates a new unit weight based on the number of items in a weighing machine or multiple weighing machines, and uses this new unit weight when calculating the next number of items, and we have previously filed an application for this.

Here, we will discuss the new unit weight calculation method in the conventional method. For example, the first method is to take an example of the conventional new unit weight calculation. After the combination calculation, based on the result, when the item is discharged from the weighing machine, whether the weight of the discharged item is equal to the set weight or not. Alternatively, there is a method in which the new unit weight is calculated by dividing the combined weight closest to it by the number of items discharged, that is, the set number. This new unit weight is stored in the calculation control section 4 and used for the next combination calculation.

There are several other methods for calculating new unit weights, but after converting the weight measured by each weighing machine into the number of pieces and calculating the combination of numbers, the item is discharged from the weighing machine corresponding to the combination that satisfies the conditions. The unit weight is recalculated and stored to be used for the next combination counting. If we examine this in detail, at that time, all the weights of each weighing machine are memorized and divided by the newly memorized unit weight to find the number of each piece. However, the discharge of goods according to the previous calculation result is not for all weighing machines. In other words, there are some weighing machines in which the items from the previous combination counting remain as they are without being ejected. However, in the next calculation, the newly stored unit weight is used to convert the weights of all weighing machines into the number of pieces. If the unit weight of a new item put into the weighing machine changes after repeating this operation several times, the item in the weighing machine that has not been discharged several times will be divided by the appropriate unit weight. This may cause calculation errors.

Therefore, in view of the above-mentioned drawbacks, the present invention improves and eliminates this problem, and in the next calculation, the newly memorized unit weight is converted into the number of pieces by discharging it from the previous time.
Only weighing machines that have been reloaded with new weighing items will be accepted.

In other words, the present invention does not perform calculations to convert items in the weighing machine that were not discharged last time into numbers using new unit weights, but stores the number converted to pieces during the previous calculation and uses it as is for combination calculations. It is something to do. In other words, the items in the weighing machine that are not discharged will participate in the combination calculation with the number stored until they are discharged.

The present invention will be explained below based on examples.

In Figure 1, 1 ₁ ... 1 _o are n weighing machines that weigh items, and 2 is an analog weight voltage output from each weighing machine 1 ₁ ... 1 _o , which is sequentially output by a selection signal described later. It is a multiplexer, and is composed of, for example, an analog switch. 3 is an A/D converter that converts the analog weight voltage output from the multiplexer 2 into a digital weight signal; 4 is an arithmetic control unit consisting of a microcomputer, etc.; 5 is a unit weight setting unit that sets the unit weight of the item; 6 is a number setting section for setting the number of items to be counted, 7 is a weight setting section for setting the total weight of the number of items set in the number setting section 6, and 8 is a weight setting section for setting the total weight of the set number of items. An upper limit weight setting section 9 sets an upper limit weight, and a lower limit weight setting section 9 sets a lower limit weight. FIG. 2 is a flowchart showing an example of the operation of the calculation control unit 4, and this flowchart will be explained below.

A large number of items are divided into n weighing machines 1 ₁ ... 1 _o , and a start signal a is sent to the calculation control unit 4 from a packaging machine (not shown) that wraps the counted items.
, the arithmetic control unit 4 outputs the selection signal b to the multiplexer 2. According to the selection signal b, the multiplexer 2 selects only the weighing machine that was previously discharged among the weighing machines 1 ₁ ... 1 _o (since the goods are put into all the weighing machines during the first counting, all the weighing machines )
The weight values are inputted, and their analog weight voltages are sequentially output to the A/D converter 3, and each A/D converted weight is stored in the arithmetic control section 4. The arithmetic control unit 4 divides each stored weight by the stored unit weight (the unit weight set in the unit weight setting unit 5 at the time of the first counting), rounds it to an integer, and calculates the weight of each item discharged last time. Weighing machine (all weighing machines at the first counting)
1 ₁ ...1 Convert the weight of the items in _o to the number and store it. Next, according to all the combination codes, the arithmetic control unit 4 calculates the number of pieces of each weighing machine ( _all weighing machines at the time of the first counting) that were previously discharged that have already been stored and the _number of pieces that were discharged last time. A predetermined addition is performed to calculate the combination number from the number converted and stored in the previous calculation of each weighing machine, and the combination number and combination code are stored as a pair. Then, the set number set by the number setting unit 6 is compared with all the stored combination numbers, and a combination code with a matching number is searched and stored. However, if there is no combination with matching numbers, it is determined that counting is impossible, and, for example, a warning lamp is turned on and appropriate error handling is performed. Further, the arithmetic control unit 4 calculates the combined weight by adding the weights of each weighing machine 1 ₁ ... 1 _o according to the combination code whose combined number matches the set number, and calculates the combined weight from among these combined weights. A combination of weights equal to or closest to the set weight set in the setting unit 7 is searched, and one pair of combination weight and combination code is stored. The stored combined weight is then compared with the upper limit weight set in the upper limit weight setting section 8 and the lower limit weight set in the lower limit weight setting section 9, and the combined weight is not between the upper limit weight and the lower limit weight. If so, it is determined that counting is impossible and, for example, a warning lamp is turned on and an appropriate error handling operation is performed. Further, when this combined weight is between the upper limit weight and the lower limit weight, a discharge signal is outputted from the calculation control section 4 in accordance with the combination code of this combined weight. Then, the items from the weighing machine corresponding to the output ejection signal are discharged, and the number of items equal to the set number of items is sent to the packaging machine. At this time, the calculation control unit 4 calculates a new unit weight by, for example, the first method from the weight of one or more weighing machines and the number of items in the one or more weighing machines. Remember. This new unit weight will be used when calculating the number of pieces from the weight of each weighing machine 1 ₁ ... 1 _o in the next combination counting. Note that there are many other methods for determining this new unit weight, which will be explained in detail later.

After this, the next counting operation is performed in the same manner as the above operation.

First, a new article is supplied to the weighing machine from which the article was discharged, and when the start signal a is input from the packaging machine to the calculation control section 4, the weighing machine 1 ₁ ... 1 discharges the article in the same way as before. Re-memorize the weight of only _o , divide these weights by the new unit weight calculated and memorized at the previous counting, round off to a whole number, and calculate the weight of each weighing machine that discharged the item 1 ₁ ...1 Items in _o Convert the weight to the number of pieces and store it. Note that the numbers and weights of the items in weighing machines 1 ₁ ... 1 _o that were not discharged are stored as they were last time.

Furthermore, like the previous time, a search is made for a combination in which the number of combinations is equal to the set number, and the combination weight is between the upper and lower limit weights and is equal to or closest to the set weight. When a combination that satisfies the conditions is obtained, a discharge signal is output from the arithmetic control section 4 in accordance with this combination. At this time as well, calculate the new unit weight by dividing the combined weight discharged by the set number of pieces,
This new unit weight is stored in place of the new unit weight calculated and stored during the previous counting, and is used for the next counting operation. Thereafter, the new unit weight is updated in the same manner for each combination count.

In this way, in the combined counting performed using a plurality of weighing machines, the present invention uses the previous number of items as is without recalculating the number of items from the weighing machine that did not discharge the item based on the new unit weight. In this way, the probability of miscalculating the number of pieces due to recalculating the number of pieces based on the new unit weight is reduced, but the method of calculating the new unit weight that is performed every time the combination calculation is There are various methods other than the first method described, which is to divide the combined weight of the discharged combinations by the number of discharged pieces. Since the present invention can be implemented in conjunction with any of these methods, these methods will be described below in order as the second to tenth methods.

The second method is to calculate a new unit weight by dividing the median value of the combined weights by the number of combinations when there are multiple combinations whose combined number matches the set number.

The third method is when there are multiple combinations whose number of pieces matches the set number, the weight of each combination is divided by the number of pieces in each combination to find the unit weight for each combination, and then the unit weight of each combination is calculated. The average value is determined and this average value is used as the new unit weight.

The fourth method is to determine the upper and lower limits of the set number of pieces, and calculate the unit weight by dividing the weight of all or any number of combinations whose number of pieces falls within this upper and lower limit range by the number of these combinations. Then, the average value of each unit weight is calculated, and this average value is used as the new unit weight.

The fifth method is to calculate the unit weight for each combination by dividing the combined weight of all combinations by the number of pieces in each combination, then calculate the average value of these unit weights, and calculate the average value as a new unit weight. It is something that is considered important.

The sixth method is to calculate the new unit weight by dividing the total weight of all or any number of combinations by the total number of pieces added together.

The seventh method is to calculate the new unit weight by dividing the weight of the item weighed by a particular one of the weighing machines participating in the combined counting by the number of items in that weighing machine.

The eighth method is to select one of the weighing machines participating in the combination counting in a predetermined order for each weighing, and calculate the weight of the item weighed by the selected weighing machine. The new unit weight is calculated by dividing by the number of pieces.

The ninth method is to calculate the unit weight by dividing the weight of the items weighed by all or any number of weighing machines participating in the combined counting by the number of items in those weighing machines. The average value of the weights is used as the new unit weight.

The tenth method is to calculate the total weight by adding the weights of the items weighed by all or any number of weighing machines participating in the combined counting, and then add the numbers of items in those weighing machines to calculate the total weight. The new unit weight is calculated by calculating the number of pieces and further dividing the calculated total weight by the calculated total number of pieces.

The configuration shown in FIG. 1 above is an example of a configuration in which all the data to be handled is converted into digital quantities and then subjected to arithmetic processing, but the present invention can also be applied to a configuration in which arithmetic processing is performed using analog quantities. Of course, an example of the configuration of a combination counting device in this case is shown in FIG. In Fig. 3, 11 ₁ ... 11 _o are n units of weighing machines that output the weight of the item as an analog voltage, 14 is a calculation unit that has a storage unit that stores the analog weight voltage and performs analog calculations, and 15 is a calculation unit that outputs the weight of the item as an analog voltage. A unit weight setting section 16 sets the unit weight using an analog voltage, a number setting section 16 sets the number of items to be counted using an analog voltage, and 17 a total of the number of items set in the number setting section 16. A weight setting section 18 sets the upper limit of the total weight of a set number of items using an analog voltage; 19 a lower limit weight of the total weight of the set number of items; This is a lower limit weight setting section that sets the weight using an analog voltage. The combination counting operation in this configuration example is also performed in the same manner as the operation in the digital configuration example described above.

In addition, in the above-described present invention, a combination whose number of combinations matches the set number is found, but a combination closest to the set number may be found. However, in this case, the number of pieces in combination closest to the set number is not necessarily equal to the set number, so the new unit weight is calculated by dividing the combined weight by the number of pieces in combination closest to the set number.

Furthermore, in the present invention described above, any one combination, regardless of the combined weight, from among the combinations whose combined number is equal to or closest to the set number, for example, the combination initially searched to be equal to the set number, Items can also be ejected.
Therefore, in this case, the upper limit weight setting section, the lower limit weight setting section, and the weight setting section are unnecessary.

Furthermore, in the present invention described above, during a combination calculation, only one combination whose number is equal to or closest to the set number among the combination numbers calculated in the previous combination calculation is stored, When all the combination calculations are completed, it is also possible to find the combination whose number of combinations is equal to or closest to the set number among all the combinations.

As explained above, according to the present invention, in a combination counting method in which a large number of items are divided and weighed using a plurality of weighing machines, the number of items is calculated using a new unit weight that is recalculated for each combination counting. Only the items in the weighing machine that were discharged last time are counted, and for the number of items in the weighing machine that were not discharged last time, the number calculated and stored last time is used as is for the combined counting, so the number of items in the weighing machine that was not discharged last time is used as is. Even if the unit weight of the collected items changes, the probability of an error in number calculation can be reduced, and combination counting can be performed with higher accuracy.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a flowchart showing an example of operation when the method of the present invention is implemented in the configuration of FIG. 1, and FIG. FIG. 2 is a block diagram showing an example of a configuration in which calculation processing is carried out using a computer. 1 ₁ ...1 _o ...Weighing machine, 2...Multiplexer, 3...A/D converter, 4...Arithmetic control unit, 5
...Unit weight setting section, 6...Number setting section, 7...Weight setting section, 8...Upper limit weight setting section, 9...Lower limit weight setting section, a...Start signal, b...Selection signal.

Claims (1)

[Claims] 1 Weigh the items with multiple weighing machines, divide each weighed weight by the individual weight of the item to calculate the number of items in each weighing machine, and perform a combination calculation of these numbers to determine whether it is equal to the set number or Find a combination that is close to that, calculate a new unit weight based on the weight and number of items in the weighing machine, discharge the item from the weighing machine that corresponds to the combination found, and then supply a new item to the weighing machine that discharged it. In the counting method, the number of items from the weighing machine that has not been discharged is memorized as is, and the next time the combined counting is performed, the number of items is calculated by dividing the weight of the item by the new single weight. A counting method characterized in that the counting method is carried out only for weighing machines that have been discharged and new items have been supplied.