JPH0421231B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a reading device for reading a barcode printed on a medium, and particularly to an improvement of a reading device with a simple mechanism.

(b) Technical background With the recent spread of computer network systems, point of sale information management systems (Point of Sale) are becoming popular in department stores, supermarkets, etc.
(hereinafter referred to as POS) has become widely adopted. Electronic registers and stationary readers are used as terminals in POS systems. These terminals are installed at payment counters and operated by operators such as store clerks to read barcodes printed on product labels. The barcode contains the product number, product name, product value, etc. When the barcode is read, the prices are sequentially displayed on the electronic register, and finally the total price is displayed by pressing a button.

In addition to the register function, this terminal also plays a role as a data input device for an information management system that sends sales information for each product online one by one to a computer center, which comprehensively performs product management such as sales aggregation, inventory management, and purchase management. I'm getting used to it.

Therefore, consideration must be given to the reading device to ensure accurate reading so as not to degrade customer service or impede the efficiency of the POS system due to reading errors or double reading.

(c) Prior Art and Problems The conventional method will be described below with reference to FIGS. 1 and 2, taking a stationary reader used in a POS system as an example. FIG. 1 is a side view illustrating a reading device to which the present invention is applied, FIG. 2 is a perspective view showing the reading section of FIG. 1, and FIG. 3 is a timing chart of FIG. 2.

As shown in FIG. 1, the reading device 1 is equipped with an optical unit 2 and a recognition section 3 inside. It has a light emitting function that emits a laser beam from the window 4, and a sensor function that scans a bar code of an object outside the device with the emitted laser beam and reads the reflected light. The recognition unit 3 has a function of recognizing the signal read by the sensor as data.
A shutter (not shown) is provided on the front surface of the optical unit 2.

A reading window 5 covered with a glass plate is provided on the top surface of the device, and light emitted from the radiation window 4 passes through the reading window 5.
The light is emitted from the top of the device as shown by the two-dot chain line in the top view of the device. A front stand 6 and a rear stand 7 are arranged in front of and behind the reading device 1, on the right and left in the figure, a basket containing products 8 is placed on the front stand 6, and an empty basket is placed on the rear stand 7. ing.

Further, as shown in FIG. 2, two sets of transmissive sensors 9 and 10, front and rear, for detecting the product 8 are installed above the reading window 5 of the reading device 1, in front and rear relative to the direction in which the product 8 is moved. , constant light emitting elements 9a, 10a
The light is outputted to the light receiving elements 9b and 10b.

With such a configuration, the operator takes out the products 8 one by one from the basket on the front table 6, points the barcodes of the products 8 downward, and scans the predetermined space above the reading window 5 in the direction shown by the arrow in the figure. When the product 8 is passed through, the front transmissive sensor 9 detects the product 8, the shutter opens as shown in FIG. Display barcode data on the electronic register display.

Next, when the rear transmission type sensor 10 detects the product 8, the shutter is closed and the product 8 is placed in the basket on the rear stand 7.

At this time, if the product 8 is mistakenly moved in the opposite direction and passes the rear transmission type sensor 10, it will be detected but not read. This is to prevent one product 8 from being read twice.

However, this reading device 1 is equipped with two sets of transmission type sensors 9 and 10, and also has a shutter and its opening/closing mechanism on the front of the optical unit 2, which makes the mechanism complicated and increases the cost. It has the disadvantage of being old.

(d) Object of the Invention The object of the present invention is to solve the above-mentioned drawbacks, and to provide a reading device that has a simple mechanism and can prevent double reading.

(e) Structure of the Invention The present invention includes an optical unit and a reading window located in front of the light source of the optical unit, and allows a medium on which a barcode is printed to pass through a predetermined space above the reading window. A reading device that reads a barcode on a medium using irradiated light includes a storage unit that stores the read barcode data for a predetermined period of time, and a storage unit that stores the read barcode data for a predetermined period of time, and a storage unit that stores the barcode data for a predetermined period of time after the barcode of a preceding medium of a plurality of media whose barcodes are sequentially read is read. When the barcode of the subsequent media is read within the time,
Comparing means for comparing the read barcode data of the subsequent medium with the barcode data of the preceding medium read from the storage means, and when the result of the comparison by the comparing means is a match, the read barcode data of the subsequent medium is compared. When a subsequent barcode is read within a predetermined time, the reading device is configured to invalidate the preceding barcode data and the subsequent barcode data, and if they match, the subsequent barcode is read. By erasing data as invalid, double reads can be prevented by a simple mechanism that improves cost.

(f) Embodiment of the Invention An embodiment of the present invention will be described below with reference to FIG. FIG. 4 is a block diagram showing an embodiment of the present invention. The same parts as in FIG. 1 are indicated by the same reference numerals.

Although the mechanism of the reading device in the example is not shown in the diagram,
The transparent sensors 9, 10 and the shutter mechanism on the front surface of the optical unit 2 described in the conventional example are removed, and the front surface of the radiation window 4 is always open.

In FIG. 4, 11 is a primary buffer, 12 is a secondary buffer, 13 is a comparison section, and 14 is a control section.

The primary buffer 11 temporarily holds the barcode data sent from the recognition unit 3, and the secondary buffer 12
If the previous barcode data is not stored in the memory, that is, if the barcode data has been erased after a predetermined period of time (described later) has elapsed, the barcode data is immediately transferred to the secondary buffer 1 by a command from the control unit 14.
Send to 2.

Further, if the previous barcode data is stored in the secondary buffer 12, the barcode data is immediately sent to the comparison unit 13 according to a command from the control unit 14.

The secondary buffer 12 immediately sends the barcode data sent from the primary buffer 11 to the host computer according to a command from the control unit 14, holds the barcode data for a predetermined period of time, and erases it after the predetermined period of time has elapsed. Further, when a subsequent barcode is read within the predetermined time, the barcode data is sent to the comparison section 13 according to a command from the control section 14.

Here, the predetermined time is the time required for the operator to place the product whose barcode has been read in the basket, hold the next product, and have the barcode read.
T ₁ is the time it takes for an operator to read the barcode of a product held in his hand and then accidentally move it in the opposite direction and read the barcode again.
Between T ₂ , there is a clear difference in the operating time between time T ₁ and time T ₂ as an individual operator, and even at different operating speeds during busy and quiet times, there is a certain difference between time T ₁ and time T ₂ . There is a clear difference and it can be distinguished, so for example 300ms, 400ms, 800ms, 1000ms
The time is selected and set according to individual differences among operators and busy/busy times.

The comparison unit 13 compares the barcode data sent from the primary buffer 11 and the secondary buffer 12 according to a command from the control unit 13, and notifies the control unit 14 of the result of whether or not both data match. .

The control unit 14 controls each unit and, based on the comparison result sent from the comparison unit 13, when both data match, erases the barcode data sent from the primary buffer 11 as double-reading. However, if the two data do not match, a command is given to send the barcode data sent from the primary buffer 11 to the host computer.

Since it has such a structure and function, Product 8
When reading a barcode, when the power is turned on to the reading device 1, the optical unit 2 constantly emits a laser beam.
A beam is emitted, and when the product 8 passes above the reading window 4, reading is performed.

At this time, in FIG. 4, the previously read barcode data is sent to the host computer and is stored in the secondary buffer 12 for a predetermined time.
When the operator grabs the next product 8 and causes it to read the barcode, the barcode data stored in the secondary buffer 12 has disappeared since this time is longer than the predetermined time and the predetermined time has elapsed. The barcode data read later is transmitted and stored in the secondary buffer 12. When the reading operation by the operator is performed normally, the above operation is repeated.

If you accidentally move the product 8 in the opposite direction and pass the reading position immediately after reading the barcode, the barcode will be read and the operator's movement will be a reciprocating movement for a predetermined period of time. Read within. The barcode data is compared with barcode data previously read, passed through the primary buffer 11, and stored in the secondary buffer 12 in the comparator 13. As a result of the comparison, if a match is confirmed, the subsequent barcode data is erased.

Furthermore, if the barcode cannot be read when the product 8 passes through the reading position in the forward direction, and the barcode is read by passing the product 8 back through the reading position, this time the product is moved backwards. In order to pass through the reading position again in order to put it in the basket on the placing table 7, the barcode will be read twice.
In this case as well, the barcode data read later can be invalidated. In this way, by omitting the transmissive sensors 9 and 10 and the shutter mechanism, it is possible to read the barcode data even if the product 8 is passed from any direction. On the other hand, the operation of product 8 makes it more likely to be read twice,
By comparing the barcode data read before and after, double reading can be prevented.

(g) Effects of the Invention As explained above, according to the present invention, not only is the cost improved because a transmission type sensor and shutter mechanism are not used, but also double reading can be prevented. The re-reading operation when the item cannot be read is unrelated to the direction of movement of the product, so it has the effect that it is only necessary to go back.

[Brief explanation of drawings]

FIG. 1 is a side view illustrating a reading device to which the present invention is applied, FIG. 2 is a perspective view showing the reading section of FIG. 1, FIG. 3 is a timing chart of FIG. 2, and FIG.
The figure is a block diagram showing an embodiment of the present invention. In the figure, 1 is a reading device, 2 is an optical unit, 3 is a recognition unit, 5 is a reading window, 8 is a product, 9, 1
0 is a transmission type sensor, 11 is a primary buffer, 12 is a secondary buffer, 13 is a comparison section, and 14 is a control section.

Claims (1)

[Scope of Claims] 1. An optical unit comprising an optical unit and a reading window located in front of a light source of the optical unit, a medium on which a bar code is printed is passed through a predetermined space above the reading window, and the optical unit A reading device that reads a barcode on a medium using irradiated light, comprising: a storage means for storing the read barcode data for a predetermined period of time; and a storage means for storing the read barcode data for a predetermined period of time; Comparing means for comparing the read barcode data of the subsequent medium with the barcode of the preceding medium read from the storage means when the barcode of the subsequent medium is read within a predetermined time from A reading device characterized in that, when a match is found as a result of the comparison by the comparison means, the read barcode data of the subsequent medium is invalidated as having been read twice.