JP2011059831A - Automatic reading method of bar code - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic reading method of a bar code attached to edges which become irregular due to differences in conveyance positions or billet lengths. <P>SOLUTION: The automatic reading method of a bar code for reading the bar code attached to the edges of billets by a camera includes: detecting the edge position of the billet; switching the zoom position of the camera; and reading the reading position of the bar code while being matched with the edge face position of the billet. Preferably, the method includes: detecting presence of the existence of the billet at each sensor position by a material load sensor installed at a plurality of places; and detecting the edge face position of the billet by discriminating the length of the billet, in the detection of the edge position of the billet. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an automatic barcode reading method for reading a barcode attached to an end face of a steel piece with a camera. More specifically, the present invention relates to a method for automatically reading a two-dimensional barcode to be given for carrying in and managing quality information of a steel piece as a material in, for example, a bar wire factory.

  Conventionally, at the bar wire factory, the identification number was written with the paint on the end face of the steel slab, and human identification was performed.However, incorrect recognition of the paint or incorrect identification by the human causes mixing of different materials. As a countermeasure, an automatic reading method has been proposed in which a barcode with an identification number or the like input is read by a camera.

  For example, Japanese Patent Application Laid-Open No. 5-28311 describes a method of moving the camera so that the distance from the reading surface is constant, and Japanese Patent Application Laid-Open No. 3-24679 is used to correct the distance fluctuation with the reading surface with a zoom camera. In addition, Japanese Patent Laid-Open No. 2006-92263 describes a method of interlocking a laser distance meter and a camera zoom.

  However, these conventional techniques are based on the premise that the barcode reading surface is aligned in advance and the variation is small, and none of these methods assume a large adjustment allowance for the reading position. It could not be applied to automatic reading of barcodes attached to the end face where the end faces were not aligned and the position variation was large.

Japanese Patent Laid-Open No. 5-28311 JP-A-3-24679 JP 2006-92263 A

  An object of the present invention is to solve the above-mentioned problems of the prior art and to provide an automatic reading method of a bar code attached to an end face that is uneven due to a difference in the length of a steel piece.

The present invention solves the problems of the prior art as described above, and has been made as a result of intensive studies. The gist of the present invention is as follows.
(1) A barcode automatic reading method that reads a barcode attached to the end face of a steel piece with a camera, detects the position of the end face of the steel piece, and switches the zoom position of the camera based on the position information. An automatic barcode reading method, wherein the barcode reading position is read according to the end face position of the steel piece.
(2) The position of the end face of the steel slab is detected by detecting the presence or absence of a steel slab at each sensor position by means of load sensors installed at a plurality of locations, and determining the length of the steel slab. The bar code automatic reading method according to (1), wherein an end face position is detected.
<Action>
According to the invention of (1), by detecting the end face position of the steel slab, switching the zoom position of the camera, and reading the barcode reading position in accordance with the end face position of the steel slab, The barcode attached to the irregular end face can be accurately read as an image of almost the same size.
According to the invention of (2), the position of the end face of the steel slab is detected by detecting the presence or absence of the steel slab at each sensor position by means of material sensors installed at a plurality of locations, and determining the length of the steel slab. By detecting the position of the end face of the steel slab, it is not necessary to prepare the barcode reading surface in advance as in the prior art, and the present invention can be applied even when the adjustment margin of the reading position is large.

  According to the present invention, it is possible to provide an automatic reading method of a barcode attached to an end face that is uneven due to a difference in a conveyance position or a steel piece length, and it is not necessary to prepare a barcode reading surface in advance, It can be applied even when the adjustment cost of the reading position is large, and has an industrially significant effect.

It is a figure which illustrates the apparatus structure in embodiment of this invention. It is a figure which illustrates the system configuration to which the present invention is applied. It is a figure which illustrates the processing flow of this invention. It is a figure which illustrates the switching pattern of the zoom position in this invention.

  The present inventors examined a method of strengthening identification management by attaching a label in which the identification number is converted into a two-dimensional barcode to the end face of the steel piece and automatically reading it using a camera.

  Specifically, the identification number read from this bar code is sent to the process computer that manages the product in the line, and it is linked to the prevention of dissimilar materials by collating with production instructions and production results (piece results). It is possible to improve the accuracy of quality control information from steelmaking to bar wire products. When performing this identification management, the automatic reading of the bar code affixed to the end face of the steel slab must be performed in a place where the end face does not align at a fixed position and varies up to 6 m due to variations in the length of the steel slab.

Embodiments for carrying out the present invention will be described in detail with reference to FIGS. 1-4, 1 is a barcode to be read, 2 is a read-only camera, 3 is a transfer control sequencer for controlling the transfer of a steel piece, 4 is an IO device that outputs a zoom switching signal to the camera, 5 is a barcode reading personal computer for identifying a barcode, 6 is a process computer for collating an identification number obtained from the barcode with a production instruction, and 7 is a position of a conveyance stop stopper. A to C are reading positions to be switched by zooming of the camera. A corresponds to a steel piece a end face reading position, B corresponds to a steel piece b end face reading position, and C corresponds to a steel piece c end face reading position. Also, (a), (b) and (c) are materials installed to discriminate which of the three types of steel pieces a, b, and c are in order to detect the end face position of the steel pieces. It is a load sensor.
FIG. 1 is a diagram illustrating a device configuration in an embodiment of the present invention. First, the read-only camera 2 is installed at a position where the end face of the steel piece can be imaged. It is preferable that the camera 2 has a zoom function that can change the reading position, and a camera that can change the zoom position by a combination of signals from the outside can be applied to automatically adjust the brightness of the image.

  As shown in FIG. 1, the present invention is an automatic reading method of a bar code 1 that reads a bar code 1 affixed to the end faces of steel pieces a, b, c with a camera 2. The end face position of c is detected, the zoom position of the camera 2 is switched, and the reading position of the bar code 1 is read according to the end face position of the steel pieces a, b, c.

  The ends of the steel pieces a, b and c that have been transported are brought into contact with the transport stop stopper 7 by bringing the end surface on the side to which the bar code is not affixed, and then transferred onto the weighing machine. By detecting the end face position of steel slabs a, b, c, switching the zoom position of the camera 2, and reading the barcode 1 according to the end face position of the steel slabs a, b, c, the length of the steel slab Bar codes attached to end faces that are uneven due to the difference in size can be accurately read as images of almost the same size.

  The detection of the end face position of the steel slabs a, b, c is performed by detecting the presence or absence of the steel slab at each sensor position by means of the load sensors (a), (b), (c) of the steel slab. By detecting the end face position of the steel piece by discriminating the length type, it is not necessary to prepare the barcode reading surface in advance as in the prior art, and it can be applied even when the adjustment cost of the reading position is large. In the present invention, the material sensors (a), (b) and (c) are not limited, but can be accurately detected in a non-contact manner by using, for example, an electromagnetic induction proximity sensor. .

The barcode applied to the present invention is preferably a two-dimensional barcode that can be recognized by two cut-out symbols, and the lighting method of the end face of the steel piece to which the barcode is attached is illuminated from the top of the steel piece. Since the light is uniformly applied by the diffusion type illumination performed, erroneous recognition can be prevented.
FIG. 2 is a diagram illustrating a system configuration to which the present invention is applied. As shown in FIG. 2, the position information of the steel piece end face detected by the material sensors (a), (b), (c) is sent to the IO device 4 via the transfer control sequencer, and the camera 2 After the zoom switching signal is output, a barcode image is taken, the barcode is read by the reading personal computer 5, and the process computer 6 compares the identification number obtained from the barcode with the production instruction.

  FIG. 3 is a diagram illustrating a processing flow of the present invention, and FIG. 4 is a diagram illustrating a zoom position switching pattern in the present invention.

  An embodiment of the present invention will be described in detail along the processing flow shown in FIG.

  First, when the steel slab arrives at the top of the weighing machine (S-1), the load sensors (a), (b), (c) operate to detect the presence or absence of the steel slab at each sensor position (S -2) The signal is input to the transport control sequencer 3.

  Next, the transfer control sequencer 3 determines the length of the steel slab (S-3), outputs a signal corresponding to the zoom position of the camera 2 to the IO device 4, and the zoom position corresponding to the length of the steel slab. A command to switch to any one of A to C is output to the camera (S-4).

  The combination of the output (ON, OFF) of the material load sensors (a), (b), (c) and the zoom position is illustrated in FIG. As shown in FIG. 4, when all of the load sensors (a), (b), and (c) are ON, the zoom position is A. When the load sensors (b) and (c) are ON, When the zoom position is B and only the material sensor (c) is ON, the zoom position is C. After switching the zoom position, an image with the barcode is taken and transmitted to the reading personal computer 5 (S-5).

  The reading personal computer 5 transmits the identification number from the photographed barcode image to the reading process computer 6 (S-6), and collates the transmitted identification number with the production instruction (S-7).

  The process computer 6 outputs the determined result to the conveyance control sequencer 3. If OK, the steel material is conveyed to the next process, the next material is waited, and the process returns to S-1 (S-8).

  On the other hand, if the determination result is NG, the conveyance is stopped, and the identification by the operator is performed (S-9).

  As described above, according to the present invention, the position of the end face of the steel slab is detected, the zoom position of the camera is switched, and the reading position of the barcode is read according to the end face position of the steel slab. The bar code affixed to the non-aligned end face that cannot be read by the mechanism that aligns the reading position with the end face can be read accurately.

  The present invention has a large variation in the reading surface of the reading object to which the barcode is attached, and in a line for manufacturing an object in which the reading surface cannot be physically aligned by moving the reading object physically, Since the production quality can be applied for improvement, it can be applied to various steel production lines.

1 Barcode 2 Camera 3 Transport control sequencer 4 IO device 5 Bar code reading personal computer 6 Process computer 7 Transport stop stopper
A Steel slab a End face reading position
B Steel slab b End face reading position
C Steel slab c End face reading position
(a) Steel bill a detection material load sensor
(b) Steel bill b detection material load sensor
(c) Steel bill c detection material load sensor

Claims (2)

  A bar code automatic reading method for reading a bar code affixed to the end face of a billet with a camera, detecting the position of the end face of the billet piece, switching the zoom position of the camera based on the position information, and An automatic barcode reading method, wherein the code reading position is read according to the end face position of a steel piece. The detection of the end face position of the steel slab is performed by detecting the presence or absence of a steel slab at each sensor position by means of material sensors installed at a plurality of locations, determining the length of the steel slab and determining the end face position of the steel slab. 2. The bar code automatic reading method according to claim 1, wherein the bar code is automatically detected.

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