JPH0535902A - Bar code reader - Google Patents

Abstract

PURPOSE:To make it possible to perform the generation timing setting of a margin detection signal to be adjusted according to the size of the bar of a bar code label to be read and the reading position without designating the setting by a switch, etc., by determining it by step by step calculation, etc. CONSTITUTION:This device has a digital signal analysis part 4 including a scanning part 1, a light receiving part 2, an A/D conversion part 3 and a programmable timer 41, and a decoding part 5 including an electric writable/ erasable ROM 55. A margin detection signal generation timing is enabled to change by margin detection signal generation timing data 104 given from the decoding part 5 to the programmable timer 41 and the generation timing of an optimum margin detection signal for a bar code label to be read in the decoding part 5 is automatically determined.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bar code reading device, and more particularly to a bar code reading device in which a bar code reading device determines a timing for generating a margin detection signal in reading a bar code.

[0002]

2. Description of the Related Art In a conventional bar code reader, the margin detection timing of a margin detection signal adjusted according to the bar size of a bar code label to be read and the reading position is as shown in FIG. The CPU of the decoding unit reads and gives the margin detection signal generation timing data by a switch or the like.

[0003]

By the way, in this conventional bar code reader, the bar code label is cleared and the time when the scanning beam scans the bar is determined by the position where the bar code label is read and the inclination of the bar code label. Therefore, there is a problem in that the work is complicated because the margin detection signal generation timing data must be specified by a switch or the like in consideration of the above calculation.

The present invention has been made in view of the above-mentioned problems, and a bar code reading device is provided in which the margin detection signal generation timing is calculated one by one and the margin timing can be set without specifying it by a switch or the like. For the purpose of providing.

[0005]

In order to achieve the above object, a bar code reading apparatus of the present invention is a bar code reading apparatus which generates a margin detection signal based on margin detection signal generation timing data. The configuration is such that a timing determination means for determining timing is provided.

Further, a scanning section for outputting a scanning beam for scanning the bar code label on the article, a light receiving section for receiving the reflected light from the bar code label and converting it into an electric signal, and an analog signal from the light receiving section are digitalized. A / D to convert to signal
A digital signal analysis unit that receives the digital signals from the conversion unit and the A / D conversion unit and generates the black width data, white width data and margin detection signal of the barcode, and the black width data and the white width from the digital signal analysis unit. A bar code reader having a decoding unit for receiving data and a margin detection signal, decoding the bar code, and sending the margin detection signal generation timing data to the digital signal analysis unit, the margin detection signal being provided in the digital signal analysis unit. A programmable timer whose generation timing can be changed in a programmable manner, a timing determination function for determining the margin detection signal generation timing data to be given to the programmable timer, and the determined margin detection signal generation timing data can be electrically written / erased. Writing to EEPROM and writing A configuration equipped with a function.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration block diagram of a bar code reader according to an embodiment of the present invention. In the figure, 1 is a scanning unit that outputs a scanning beam, 2 is a light receiving unit that receives reflected light from a barcode label and converts it into an electrical signal, and 3 is an A that converts an analog signal from the light receiving unit 2 into a digital signal.
It is a / D converter. A digital signal analysis unit 4 receives the digital signal from the A / D conversion unit 3 and generates a margin detection signal 103 by the black width data 101, white width data 102 of the bar code and the programmable timer 41.

A decoding unit 5 receives the black width data 101, the white width data 102 and the margin detection signal 103 from the digital signal analyzing unit 4 and decodes the bar code, ie, the CPU 51, the ROM 53, the RAM 54 and E.
It is composed of the EPROM 55. The decoding unit 5 has a timing determining function for determining the margin detection signal generation timing data to be given to the programmable timer 41. The EEPROM 55 writes and holds the determined margin detection signal generation timing.

Generally, since there is a clear area called a margin before and after the bar code of the bar code label, it is understood that if the margin is detected, the bar code exists between them.

Therefore, in order to detect the margin,
The digital signal analysis unit 4 generates the margin detection signal 103 when the scanning beam scans the clear area having a certain width or more, but the decoding unit 5 digitally outputs the margin detection signal generation timing data 104 defining the clear area having a certain width or more. The generation timing of the margin detection signal 103 is changed by giving it to the programmable timer 41 of the signal analysis unit 4.

Next, the operation of the embodiment will be described with reference to the operation flow example of FIG. In the margin setting mode (2-1), the margin detection signal generation timing data 104 is sequentially changed (2-4) (2-3), and the number of pattern cutouts during a fixed time is counted (2-4). When the predetermined condition is satisfied (2-5) (2-6) (2-7) (2-8), the optimum margin detection signal generation timing data 104 for the bar code label is written and held in the EEPROM 55 of the decoding unit 5. (2-9).

When the margin setting mode (2-1) is not set, the margin detection signal generation timing data 104 written in the EEPROM 55 of the decoding section 5 is given to the programmable timer 41 of the digital signal analysis section 4 (2-10).

[0013]

As described above, according to the bar code reader of the present invention, the optimum margin detection generation timing is determined only by reading the bar code of the bar code label. The margin detection signal generation timing does not have to be calculated and specified with a switch as was done in the past, and even a person who does not know how to calculate the margin detection signal generation timing can set the optimum margin, and the bar code reader This has the effect of facilitating the construction of a system using.

[Brief description of drawings]

FIG. 1 is a configuration block diagram showing a barcode reading device according to an embodiment of the present invention.

FIG. 2 is an operation flowchart of the barcode reading apparatus according to the embodiment.

FIG. 3 is an operation flowchart of a conventional barcode reading device.

[Explanation of symbols]

1 scanning unit 2 Light receiving part 3 A / D converter 4 Digital signal analysis section 5 Decoding section 41 programmable timer 51 CPU 52 switch 53 POM 54 PAM 55 EEPROM 101 Black width data 102 White width data 103 Margin detection signal 104 Margin detection signal generation timing data

Claims (2)

[Claims] 1. A bar code reading apparatus for generating a margin detection signal based on margin detection signal generation timing data, comprising a timing deciding means for deciding the margin detection signal generation timing. . 2. A scanning unit which outputs a scanning beam for scanning a bar code label on an article, a light receiving unit which receives reflected light from the bar code label and converts it into an electric signal, and an analog signal from the light receiving unit is digitalized. From the A / D conversion unit for converting into a signal, the digital signal analysis unit for receiving the digital signal from the A / D conversion unit and generating the black width data, the white width data of the barcode and the margin detection signal, and the digital signal analysis unit. Of the black signal, the white signal, and the margin detection signal, the bar code is decoded and the margin detection signal generation timing data is sent to the digital signal analysis section. And a programmable timer that can change the margin detection signal generation timing in a programmable manner. And a write function for writing and holding the determined margin detection signal generation timing data in an electrically writable / erasable EEPROM. Characteristic bar code reader.