JPH0233147Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a price scale that calculates a price by multiplying the weight of an object to be weighed by a unit price, and particularly relates to a device that verifies the multiplication.

In conventional price scales, a multiplier multiplies the value stored in the unit price register, which stores the price per unit weight of the object to be weighed, by the value stored in the weight register, which stores the weight of the object. and calculated the price. However, with this multiplier, errors in multiplication could occur due to external noise or defects in the semiconductors that make up the multiplier.
If this mistake is not discovered, erroneous commercial transactions will occur, which is very inconvenient. Conventionally, as a device for checking the above calculation, for example,
There is one as disclosed in Publication No. 66160.
This is calculated by (1) multiplying the unit price by 1 and the complement of the weight, (2) multiplying the unit price by 1 and the weight, and (3) by (1) and (2). Subtract the value obtained by adding 1 to the unit price, and if the subtracted value is 0, it is normal.
If it is not 0, it is determined that there is an abnormality.
However, this only determines whether the weight and its complement were input correctly, and cannot determine whether the price calculation in the multiplier was performed normally.

The object of this invention is to provide a device for checking whether the above-mentioned multiplication is incorrect.

This invention will be explained below based on one embodiment shown in the drawings. In the figure, the part surrounded by the dashed line is
This is a billing device based on this invention, and the other part is a fare scale part.

For convenience of explanation, the configuration of the fee scale will be explained first.

1 is a unit price register, and by operating a push button 2, the price (unit price) per unit weight of the object to be weighed is stored. A weighing signal register 3 stores a weighing signal proportional to the weight of the object to be weighed, which is calculated by a weighing mechanism (not shown) and converted into a digital quantity by the analog-to-digital converter 4. A proportional constant register 5 stores a proportional constant of the weighing signal to the weight of the object to be weighed. This proportionality constant is generally referred to as a span constant or a span coefficient. For example, when objects to be weighed weighing 2,500 g and 5,000 g are respectively loaded on the weighing mechanism, the digital output of the analog-to-digital converter 4 should be "2,500 g. ", "5000" should be obtained, but due to variations in the metering mechanism or the analog-to-digital converter 4, only digital outputs such as "2450" and "4900" may be obtained. In order to change this into the digital value that should originally be obtained, the proportional constant of the proportional constant register 5 and the measurement signal of the measurement signal register 3 are multiplied by the multiplier 6. In the above example, the proportional constant stored in proportional constant register 5 is
5000/4900≒1.0204. The multiplied value of the multiplier 6 is stored in the weight register 7. A multiplier 8 multiplies the value stored in the weight register 7 and the value stored in the unit price register 1 to calculate the price. 9. If the calculated price has a value below the minimum currency unit, round it up or down, round the price to the minimum currency unit, and when rounding, add the value for rounding up or subtract for rounding down. It is a price correction device that stores values. 10 is the price register,
Remember rounded prices. The values stored in unit price register 1, weight register 7, and price register 10 are as follows:
The signal is supplied to the decoder driver 11 in a time-sharing manner and displayed on the display device 12.

Next, the verification device will be explained. The stored values of the price register 10 and the weight register 7, which are calculated and stored as described above, are supplied to the decoder driver 11 and are also stored in the verification price register 15 and the verification weight register 16, respectively. Since the stored value stored in the verification price register 15 is rounded up or down by the price correction device 9, the value below the minimum passing unit is rounded up or down.
The price correction device 17 returns the price to the original state without rounding up or down, that is, the price calculated by the multiplier 8, and stores it in the price correction device 17. This price restored to its original value is supplied to the divider 18,
It is divided by the value stored in the weight register 16 for verification, and the division result is stored in the unit price register 19 for verification. The value stored in the unit price register 19 for verification is compared with the value stored in the unit price register 1 by a comparator 20. If the compared values are not equal, comparator 20 provides a signal to OR circuit 21 .

The value stored in the weight register 16 for verification is also supplied to the divider 22 and divided by the value stored in the proportional constant register 5, and the result of this division is stored in the weighing signal register 23 for verification. This stored value is compared with the stored value of the weighing signal register 3 by the comparator 24. When the compared values are not equal, the comparator 24 supplies a signal to the OR circuit 21.

25 is an analog-to-digital conversion error detector;
A signal is supplied to the OR circuit 21 when a conversion error occurs when converting a measurement signal from an analog quantity to a digital quantity.

When the OR circuit 21 receives a signal from one of the comparators 20, 24 and the conversion error detector 25, it issues an output signal and either erases the digital display on the scale or displays a transaction abort. , which renders the scales untradeable.

A calculation device check weight register 27 is connected to the check weight register 16 via a switch 26 . The inspection weight register 27 stores a predetermined weight value, and the stored value is stored in the verification weight register 16 only while the switch 26 is closed. At this time, it is assumed that a value different from the value stored in the inspection weight register 27 is stored in the weight register 7, for example, by loading an article with a weight different from the predetermined weight on the weighing mechanism. Assuming that the divider 18 is operating normally, the unit price calculated by the divider 18 and stored in the verification unit price register 19 is a different value from the unit price stored in the unit price register 1.
Similarly, if the divider 22 is operating normally, the divider 22 adds the signal to the verification weighing signal register 2.
The measurement signal stored in the measurement signal register 3 has a different value from the measurement signal stored in the measurement signal register 3. Therefore, if the comparators 20 and 24 generate signals, it can be seen that the dividers 18 and 22 are operating normally.

Also, as shown by the dotted line in the figure, the check price register 29 is connected to the check price register 15 via the switch 28, the switch 26 is opened, the switch 28 is closed, and the check price register 15 is connected to the check price register 15. If a value different from the value stored in the price register 10 is stored, only the divider 18 can be checked.

In the verification device configured in this way, the divider 1
Divide the price value by the weight value by 8, multiplier 8
We are checking whether the multiplication by is correct. Further, the weight value is divided by a proportionality constant by the divider 22, and it is verified whether the multiplication by the multiplier 6 is correct. Therefore, erroneous commercial transactions due to failures of the multipliers 6 and 8 are prevented.

In the above embodiment, in order to verify the multiplication by the multiplier 8, the value stored in the price register 15 for verification is divided by the value stored in the weight register 16 for verification. A unit price register may be provided, and the value stored in the price register for verification 15 may be divided by the value stored in the unit price register for verification, and the result may be compared with the value stored in the weight register 7. Further, in this case, instead of the comparator 20, a detector may be provided that generates a signal when the division result has a value below the decimal point.

[Brief explanation of the drawing]

The figure is a block diagram of a toll scale implementing an arithmetic device according to this invention. 1...Unit price register, 7...Weight register, 8
... Multiplier, 9 ... Price correction device, 10 ... Price register, 15 ... Price register for verification, 16 ...
...Weight register for verification, 17...Price correction device for verification, 18, 22...Divider, 20, 24...Comparator, 27...Weight register for inspection, 29...Price register for inspection.

Claims (1)

[Claims for Utility Model Registration] A weighing signal register that stores a weighing signal proportional to the weight of the object to be weighed, a proportionality constant register that stores a proportionality constant of the weighing signal to the weight of the weighing object, and the weighing signal. a first multiplier that multiplies the value stored in the register by the value stored in the proportionality constant register; a weight register that stores the multiplication result; and a unit price that stores the unit price that is the price per unit weight of the object to be weighed. In a price scale comprising a register, a second multiplier that multiplies the value stored in the unit price register by the value stored in the weight register, and a price register that stores the multiplication result, the value stored in the price register is a price register for verification that stores the value of the weight register for verification, a weight register for verification that stores the value stored in the weight register, and a first divider that divides the value stored in the price register for verification by the value stored in the weight register for verification; , a first comparator that compares the division value of the first divider with the value stored in the unit price register and generates a signal if these two values are different; a second divider that divides by the value stored in the proportionality constant register; and a second comparison that compares the division value of the second divider with the value stored in the measurement signal register and generates a signal if these two values differ. vessel and the first or second
and an OR circuit which generates an output when the output of the comparator is input, thereby disabling transactions on the toll scale.