JPH0786899B2 - Barcode reading method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a barcode reading method, and more particularly to a barcode reading method inscribed on the surface of a metal article by laser marking or the like.

[Prior Art] In recent years, barcodes have been used in various fields, and the configuration of the barcode portion is the same as that of the information carrier disclosed in Japanese Utility Model Laid-Open No. 62-81168, which uses a reflective tape to convert the barcode. It can be formed to enable identification from a long distance, and it can also be used in actual development.
Like the bar code reader shown in the -51562 publication,
Various types of means for improving the barcode reading ability are disclosed, such as providing a reflecting plate on the surface of a mounting table on which a sheet with a barcode attached is formed so that the barcode can be identified even on a transparent sheet. Has been done.

On the other hand, in a production line of a factory or the like, a label on which a bar code is printed is attached to the surface of a metal article, and the metal article is identified by reading the label. However, in such a case where a label is attached to a metal article, the label is damaged in the steps such as heat treatment and cleaning of the metal article, and therefore it is necessary to reattach a new label every time these steps are performed.

Therefore, from the viewpoint of labor saving of the production line, it is considered to engrave the bar code on the surface of the metal article by using a means such as laser marking or engraving.

[Problems to be Solved by the Invention]

However, the bar code engraved on the surface of the metal article has a small difference in reflection / absorption of the light beam, so the contrast of the reflected light incident on the light receiving portion is weak, and the light receiving portion cannot be sufficiently identified. It was That is, in the case of a barcode printed on a paper surface or the like, it can be clearly divided into a part where the light beam is reflected and a part where the light beam is absorbed,
When a bar code is engraved on the surface of a metal, the light beam is reflected in only one direction on the surface of the metal where the bar code is not engraved, and the light beam is diffusely reflected on the engraved part. There is no part that absorbs the light beam like the bar code No. 3, the reflected light does not have a sufficient contrast for the light receiving part to identify, and it cannot be read by the light receiving part of a normal bar code reader.

Therefore, it is an object of the present invention to provide a barcode reading method capable of reliably reading a barcode engraved on the surface of a metal article.

[Means for Solving the Problems]

In order to achieve the above object, the present invention, when reading a bar code engraved on the surface of a metal article, irradiates the bar code section on the surface of the metal article with a light beam from a light projecting section of the bar code reader. Then, the light beam is reflected on the surface of the metal article, a bar code is projected on a reflecting plate arranged at a position where the light beam is reflected, and the bar code image projected on the reflecting plate is received by a bar code reader. The feature is that it is read by the department.

[Work]

As described above, when the light beam is reflected on the surface of the metal article and projected on the reflection plate, the portion where the light beam is reflected on the surface of the metal article toward the reflection plate has high brightness on the reflection plate.
Since the irregularly reflected portion of the engraved portion of the barcode forms a shadow on the reflection plate, it is possible to obtain a sufficient light amount difference for the light receiving portion to identify.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

The bar code reading device 1 integrally forms a light projecting portion 2 for the light beam L and a light receiving portion 3 for the reflected light R, and the He-
A narrow light beam L such as a Ne laser is emitted toward the bar code C, the reflected light R from the bar code C portion is received by the light receiving section 3, and the bar code C is identified. It has an internal structure substantially similar to.

On the other hand, on the surface S of the metal article M, a marking portion Cd is engraved by means of laser marking using a pulse mode laser, engraving or the like, and a predetermined bar code C is formed by unevenness. This metal article M is, for example, a stainless plate,
It is a general metal material such as a plate material such as a rope plate, an aluminum plate, or a shape member such as a shape rope or an aluminum extruded material, and almost any material can be used as long as it has no unevenness on the surface.

Then, the metal article M is read by the barcode reading device 1.
When reading the bar code C engraved above, the reflection plate 4 is arranged at a position facing the bar code reading device 1 with the bar code C portion interposed therebetween.

As for the position of the bar code reading device 1 at this time, it is necessary to select the irradiation angle θ of the light beam L so that the bar code is clearly projected on the reflection plate 4. Further, the distance between the barcode reading device 1 and the barcode C and the barcode C
The appropriate distance between the reflector and the reflection plate 4 is about 50 mm.

The reflection plate 4 is formed of a light-colored material, and a white material such as white paper is particularly preferable. The reflection plate 4 can be easily formed by adhering the white paper to an appropriate plate material.

When the light beam L is irradiated toward the bar code C portion in this state, the irradiated light beam L on the surface S of the metal article M.
Is reflected (Lr) only in the direction toward the reflection plate 4, so that most of it reaches the reflection plate 4 and forms a high-brightness portion B, while the light beam L is irregularly reflected (Ld) at the engraved portion Cd of the bar code C. As a result, the amount of light reaching the reflection plate 4 is reduced and the low brightness portion D is formed on the reflection plate 4.

As described above, the bar code C portion is projected on the reflection plate 4 by utilizing the reflection property of the light beam L, so that the light and dark portions composed of the high brightness portion B and the low brightness portion D are clearly formed on the reflection plate 4. The barcode image F can be formed, and the light receiving unit 3 can obtain the contrast necessary for identifying the barcode C. At this time, by making the surface of the reflection plate white as described above, the absorption of light by the reflection plate can be reduced, and a clear barcode image can be obtained. Further, if it is possible to obtain a sufficient brightness difference between the high-luminance portion B and the low-luminance portion D, the reflecting plate can be formed by using another coloring material.

Then, by reading the bar code image F projected on the reflection plate 4 by the light receiving unit 3 and identifying it, the bar code C directly formed on the surface of the metal article M can be identified. This eliminates the need to attach a label printed with a barcode to the metal article M, and the barcode is less likely to be damaged by heat treatment or cleaning.
It is possible to reliably identify the metal article.

〔The invention's effect〕

As described above, according to the present invention, since the light beam is reflected by the bar code portion on the surface of the metal article and projected on the reflection plate, the contrast sufficient for identifying the bar code at the light receiving portion of the bar code reader is provided. It is possible to obtain a bar code image having, and the bar code engraved on the surface of the metal article can be easily identified.

Therefore, by directly engraving the barcode on the surface of the metal article, the work of sticking the printed label can be omitted, and the management of the label itself is not required, so that the labor cost can be reduced and the management cost can be reduced. The cost can be reduced.

Further, according to the method of the present invention, it is only necessary to prepare a reflector in addition to the conventional bar code reader, and since this reflector can also be easily manufactured, at an extremely low cost,
Moreover, the bar code engraved on the surface of the metal article can be read by a simple operation.

And the irradiation angle of the light beam is 5 with respect to the surface of the metal article.
If it is set to ~ 30 degrees, the operability at the time of reading will be improved, and by making the surface of the reflection plate white, the projected bar code image can be made clearer and the discrimination power at the light receiving part can be improved. it can.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a bar code reading state, and FIG. 2 is an explanatory view showing a light beam reflection state. 1 ... bar code reader, 2 ... light emitting part 3 ... light receiving part, 4 ... reflector, B ... high brightness part C ... bar code, Cd ... engraving part, D ... low brightness Division, F
…… Bar code image, L …… Light beam M …… Metal article, R …… Reflected light, S …… Surface of metal article

Front page continuation (72) Inventor Hideyuki Sakamoto 1-1, Sanbonmatsucho, Atsuta-ku, Nagoya, Aichi Japan Vehicle Manufacturing Co., Ltd. (72) Toru Nakao 1-1-1, Sanbonmatsucho, Atsuta-ku, Nagoya, Aichi Japan Vehicle Manufacturing Co., Ltd. (72) Inventor Yutaka Tano 8-1 Nihonbashi Odenmacho, Chuo-ku, Tokyo Marubun Co., Ltd. (56) Reference Japanese Patent Laid-Open No. 59-201176 (JP, A) 74459 (JP, U)

Claims (1)

[Claims] 1. When reading a bar code engraved on the surface of a metal article, the bar code section on the surface of the metal article is irradiated with a light beam from a light projecting section of a bar code reader, and the light beam is projected onto the metal. Characterized in that the bar code is reflected on the surface of the article, the bar code is projected on a reflection plate arranged at a position where the light beam is reflected, and the bar code image projected on the reflection plate is read by a light receiving unit of a bar code reader. How to read the barcode.