JPS63180323A - Method for display and discharge of defective part of metal coil thin plate for can making - Google Patents

Abstract

PURPOSE:To remove a defective part surely at high speed without deforming a sheet by arranging a defect inspection device and the injecting device marking on the end edge part of a sheet as a dot mark a defective part. CONSTITUTION:A flaw inspection instrument 7 inspecting the both faces at the front and back of a sheet 1 is arranged between deflecter rolls 13, 14. This instrument 7 detects the presence or absence of the flaw on the sheet 1 by using a laser as the light source, scanning linearly on the sheet 1 via the polygon mirror rotating at high speed and photo-detecting the reflection light thereof. a defect detection signal is transmitted by discriminating at which position in the width direction of the metal coil thin plate 1 for can making the flaw is located. The injecting device 8 marking on the end edge part of the thin plate 1 is arranged by fitting it to its follow-up device 8a between the tension rolls 16, 18 in the down stream of this device 7 to perform the marking by a dot line surely at high speed and with noncontact.

Description

Detailed Description of the Invention (Industrial Application Field) This invention is for displaying defective portions existing in a metal coil thin plate for can manufacturing when punching can lids or can bodies for canned foods, etc. The present invention relates to a method for displaying defective parts and a discharge method for removing the defective parts using this display.

(Prior art) If there are pinholes in thin metal coil sheets for can manufacturing, which are used to make cans for canned foods, etc., there will be problems with leakage, and if there are flaws, problems such as cracks and breakage will occur during can manufacturing. wake up

Traditionally, if a defective part existed in this thin coil sheet, the steel manufacturer either inspected it for pinholes or flaws and marked the area before supplying it to the can manufacturer, or there was no way to remove the defective part in the coil state. For quality control reasons, can manufacturers remove several dozen times as many defective parts from punched products.

Therefore, from this removed portion, a large number of defective products and non-defective products have to be sorted out, and a large number of man-hours are required for the sorting.

In addition, there are some items that cannot be sorted out for food hygiene reasons, and all the removed items may be lost, making the removal of defective parts from thin metal coil sheets for can manufacturing extremely low yields. ing.

(Problems to be Solved by the Invention) For this reason, as a method for indicating defects in metal coil thin plates for can manufacturing, a method using magnetic marks has been proposed, for example, as disclosed in Japanese Patent Application Laid-open No. 71523/1983. . This is an excellent method and is harmless in terms of food hygiene, but because it uses magnetism, it is limited to steel plates and cannot be used for anything other than steel plates. In addition, magnetic marks attached to steel plates may disappear due to temperature, bending, etc., and the distance between magnetic marks is 300 to 41 mm due to magnetic interference.
There was a problem in that it required a length of 10 mm or more.

In addition to this, it is also possible to make holes with a punch or mark marks with flaws on the metal coil thin plate for can manufacturing, but this would generate chips and hair.

It is not desirable in terms of quality for use in food cans.

Furthermore, it is possible to consider a method of marking by laser or printing, or the speed of the line is 100 to 500 per minute, such as a coil thin plate coating line or a coil thin plate manufacturing line.
It is extremely difficult to do this at speeds as fast as a turtle.

An object of the present invention is to provide a novel and reliable method for indicating defects in a metal coil thin plate for can manufacturing, which is completely harmless in terms of food hygiene, and a method for discharging defects using the same.

(Means and effects for solving the problems) The present invention was made in view of the above-mentioned problems. A device is used to mark the product, and when the marked coil is used to punch out can lids, etc., the mark detection device detects the defective part and removes the product containing the defective part. Therefore, the product punched from the defective part of the material is reliably removed, and the area to be removed is reduced to improve yield.

Also, by marking the position within 1 oan from the edge of the metal coil thin plate for can manufacturing, if the thing punched from the metal coil B plate for can manufacturing is a can lid, it is possible to tighten the seams during can manufacturing. This is located under the rubber, and in the case of a can body, because it enters the seam of the flange during can manufacturing, it is marked at a position that does not touch the contents of the can after can manufacturing. It has no effect on things at all.

(Example) Before explaining the examples, the metal coil for can manufacturing of the present invention i
The principle of the board defect display method will be explained.

This inkjet mark is safe and approved by the FDA (U.S. Food Safety and Health Administration) for food hygiene reasons, but for food hygiene reasons it is necessary to place the mark accurately within 10mW from the edge of the thin metal coil plate for can manufacturing. It is. For this reason, the inkjet device for marking is equipped with a tracking device that follows the meandering of the metal coil thin plate for can manufacturing. This tracking device may be one that moves by touching the edge of the metal coil thin plate for can manufacturing, or it may be a non-contact type for quality reasons if it is for single-serve cans due to the risk of hair or edge bending. Preferably.

A metal coil thin plate for can manufacturing is first divided in the width direction by a defect inspection device such as a flaw inspection device, a pinhole inspection device, a plate thickness gauge, etc., and defective portions are detected. When this defect inspection device detects a defective part, in synchronization with the line speed of the metal coil thin plate for can manufacturing, an inkjet device installed downstream places the defective part in a fixed position at the edge of the thin plate the moment it passes. The synchronization method for marking is carried out by means of pulses generated by a pulse generator of 1 ms provided on the pinch roller.

Marks placed on the edge of the thin plate to indicate defects should have a dot diameter of 0.2-0.3 mm, and should be arranged in rows of 1-10 dots within 10m5 of the edge of the thin plate in the width direction. A dot row pattern of 10 to 70 dots is uniformly marked with an inkjet device at a dot row interval of 0.3 to 2.0cm in the length direction of the coil, and defects existing in the coil are identified by this dot row pattern. Information about the position of the part in the width direction is also displayed.

Normally, in order to display the divisions divided in the width direction of a metal coil thin plate for can manufacturing, it is necessary to have as many as 2n patterns when dividing into n parts.According to this invention, it is possible to display as many as (n+2) columns. . However, the intervals between the mark rows need to be displayed as precise and constant dot rows.

Regarding the length direction, the problem is the speed of the inkjet device and the processing speed of the defect inspection device for dividing in the width direction. The marking speed of an inkjet device is approximately l as the time it takes from receiving a marking signal, which is a defect signal sent by the defect detection type δ, to receiving data again after marking.
Requires Osec. Therefore, the distance that the metal coil thin plate for can manufacturing moves during this time is 16 to 80 mm.
During this time, continuous marking is not possible.

In addition, it is necessary to process the defect inspection equipment to transfer the width direction signals in parallel or serially, or to combine them into one signal at the same time, and the processing time is approximately 15 seconds. The distance traveled by the thin plate is 20
~120mm. Therefore, it is necessary for the defect inspection device to detect whether there is a defective part in the thin plate in division units of 20 to 120 mm, taking into account the moving distance of both, and to mark this information. It is necessary to have a classification processing function for the direction of travel.

In this invention, in order to start marking from the beginning of the section, when a defect is detected, the defective portion is removed from the beginning of the mark along the length of the section.

Next, the marked metal coil thin plate for can manufacturing is detected by a mark detection device in a subsequent process. For this mark detection device, it is necessary to consider whether a photosensor 4CCD camera, a barcode reader, etc. is used, or the detection sensor should be considered depending on the state of the mark, the line speed of the post-process, the vibration condition of the coil, etc.

In addition, regarding the detection of marks, since the marks are placed within 101@ from the edge of the thin metal coil sheet for can making, it is necessary to eliminate false detections due to deviations in the detection position, and this also applies to the thin metal coil sheet for can making. A tracking device is required to match the meandering. For this follow-up device, either a contact type or a non-contact type is selected depending on the line speed, vibration, etc.

Based on the mark information detected by the mark detection device,
A defective portion of a thin metal coil sheet for can manufacturing is identified, and the can lid, can body, or sheet containing the defective portion is removed while timing the punched can lid, can body, or cut sheet.

As described above, the method for displaying and discharging defective parts of a thin metal coil sheet for can manufacturing according to the present invention displays positional information of the defective portion of a thin metal coil sheet for can manufacturing on the edge of the thin sheet using an inkjet device, This is detected by a mark detection device in a later punching process, and only the products or sheets containing the defective portion are discharged.

Hereinafter, based on the drawings, the metal coil for can manufacturing 8N of the present invention will be described.
An embodiment of a method for displaying defects on a board and a method for discharging using the method will be described.

FIG. 1 is an overall configuration diagram of a defect mark display line of a metal coil thin plate for can manufacturing. A thin plate 1, such as a steel plate, pulled out from the can-making metal coil 2 is coated with epoxy resin or the like on its surface using a coating Ja3, and then dried using a dryer 4. Next, the thin plate l is deflector roll 11.12
．． Tension is applied by tension rolls 15.16 through 13.14 and then a pair of pinch rolls 17.1.
The thin coil plate is cut into a predetermined length by a cutter 5 for cutting the joint part disposed between 8 and 19.20, and is wound onto a winding reel 6.

Between the deflector rolls 13 and 14, a defect inspection device for inspecting both the front and back surfaces of the thin plate l, such as a defect inspection package M7 for inspecting flaws, is disposed.

This flaw inspection device uses a laser as a light source, scans the thin plate in a linear manner through a polygon mirror that rotates at high speed, and receives the reflected light with a photo sensor to inspect the thin plate.
This is to detect the presence or absence of flaws on the surface. Then, a defect detection signal is sent out by determining where the flaw is located in the width direction of the thin metal coil plate l for can manufacturing.

Instead of this flaw inspection device, a defect inspection device such as a pinhole inspection device or a plate thickness gauge may be installed depending on the purpose.

Tension roll 16.18 downstream of this flaw inspection device 7
(17) An inkjet device 8 for marking the edge portion of the thin plate 1 or its follower device 8a is attached and disposed therebetween. This inkjet device 8 uses, for example, Unijet (trade name) manufactured by Toshitowell Co., Ltd., and can perform marking by dot rows reliably at high speed and in a non-contact manner.

Since it would be a problem if the mark attached to the edge of the -) plate l is only half-dried, a hot air dryer 9 is installed downstream of the mark and the mark is dried by blowing hot air at about 40°C. The line speed of the thin plate 1 at this time was 212 m/min, and no problems occurred with the marks made.

Further, although not shown, a pulse signal generator with a pitch of 1- is attached to the tension roll 15, and a synchronous pulse signal corresponding to the line speed of the thin plate 1 is generated. It is designed to transmit a position signal at a distance of 7 meters.

Next, the following device 8a of the inkjet device 8 will be explained with reference to the block diagram in FIG. 2 and the perspective view in FIG. 3.

An X table 25 having a screw shaft 24 is disposed at right angles to the direction of movement of the metal coil thin plate l for can manufacturing as shown by arrow A, and this screw shaft 24 has a follow-up device 8a or can move left and right as shown by arrow B. is attached to. At one end of this screw shaft 24,
A driving DC motor 26 is attached, and this DC motor 26 is connected to an input/output device 30 of a controller circuit 29 via a DC servo driver circuit 27. A pulse generator 31 is also attached to the DC motor 26 and is also connected to an input/output device 30 of the controller circuit 29.

The following device 8a on the X table 25 has an inkjet device #! Along with I8, an image sensor 32 consisting of a CCD camera for detecting the end 1a of the moving metal coil thin plate l for can manufacturing and an air cylinder core for the retractor are arranged, and this image sensor 32 is connected to an image sensor controller circuit. It is connected to the input/output device 30 of the controller circuit 29 via 33.

Furthermore, limit switches 34 and 34 are attached to both sides of the X-table 25, and these are also connected to the input/output device 30 of the controller circuit 29. The inkjet device M8 is also connected to the input/output device 30 of the controller circuit 29 via an inkjet controller circuit 35. And image sensor-3Z
As shown in FIG. 3, a light source 36 is disposed at a position facing the image sensor 32 with a thin plate 1 in between.

Further, the X table 25 is attached to the block 43,
This block 43 is fitted into a dovetail groove 44 of the machine frame 42 and is attached so as to be movable left and right.

A screw shaft 41 having a handle 40 at one end is attached to the block 43, so that by operating the handle 40, the end 1a of the metal coil thin plate 1 for can manufacturing can be adjusted.
The initial position setting of the inkjet device 8 can be easily performed.

With this configuration, the end 1a of the metal coil section plate 1 for can manufacturing is detected by the image sensor 2, and is input to the controller circuit 29 via the image sensor control circuit 33 and the input/output device 30. The moving distance is calculated by comparison with the set value, and is output to the DC motor 26 via the DC servo driver circuit 27 to control the position of the It is designed to follow and move. The distance traveled can be set with an accuracy of ±0.2 mm by inputting pulses from the pulse generator 31 to the controller circuit 29 via the input/output device 30 and repeating comparison calculations with the set value again. there were.

Note that the limit switches 34 and 34 are provided on both sides of the inkjet tracking device 8a for maintenance purposes, and the retracting air cylinder 37 is used when passing through the joint part of the metal coil thin plate 1 for can manufacturing, or when applying tension to the thin plate 1. In order to prevent the inkjet device 8 from being unable to make a mark on the thin plate 1 or a mark at a fixed position on the thin plate 1 by retracting the inkjet device 8 upward when the B plate 1 is bent due to the loss of the B plate 1. It is located in

Next, with reference to FIGS. 4 to 6, marks to be attached to the edge portions of the metal coil thin plate 1 for can manufacturing will be explained.

The marks made by the inkjet device 8 are composed of dot rows. In other words, the dot mark 5 for defect indication
1, a space of 1 l is left open from the end 1a of the thin plate 1, and the diameter of the plate is 0.2 to 0.3, or the diameter of the plate is 0.2 to 0.3. It can be attached. This means that the minimum fear that will be detected later by the mark detector is l■■
This allows for some leeway.

As shown in FIG. 5, in this example, when the thin metal coil plate l for can making is divided into 16 sections in the width direction and defective parts are displayed, the length in the traveling direction of the thin plate l of the can making coil is 17 s + s.
A dot pattern is formed with each dot as one unit. The first row of dots and the last row of dots in the 18th row are equally spaced control marks, which means that when a mark is detected, the interval between the marks is 17 mm between control marks, and when no mark exists, it is 18 mm. It can be divided because the interval is larger than that.

From the 2nd row of dot marks to the 17th row or the above thin plate l
The first section, the second section, -111 first section divided in the width direction of
For example, as shown in Fig. 6, if there is a defect such as a flaw in the second section, the dot marks attached to the edge portion 1a of the thin plate l will correspond to the 1st and 18th columns. A third row of dot marks 52 is attached to the controller mark and the first control mark within that interval at a position 21- from the first row. This indicates that a defect exists in the shaded area in FIG. 6).

This dot mark is placed by an inkjet device as position information in the width direction of the defective portion only when the defective portion exists.

In this example, the widthwise division of the metal coil thin plate l for can making is explained as 16 sections, but this can be arbitrarily set according to the width dimension of the thin plate of the can making coil used as appropriate. It goes without saying that the length division of the coil thin plate in the advancing direction can be arbitrarily set within the above range depending on the conveying speed of the thin plate.

Next, a method will be described in which a thin metal coil sheet for can manufacturing with this mark is used and the defective portion is discharged in a punching line.

FIG. 7 shows the process of the punching line.

Inspection is performed using a flaw inspection device, which is the defect inspection device described above,
The thin plate 21 pulled out from the coil 22 with a mark marked on the edge of the thin plate in the defective area passes through a pair of pinch rollers 71, 72 and 73, and is punched into a can lid or can body by a press 75. These products and the scrap sheet C after punching are separated and transported.

A mark detection sensor 76 is installed between the pinch rollers 71, 72 and 73, 74. This detection sensor 76 is composed of, for example, a photo sensor, a CCD camera, or a barcode reader. Then, an appropriate one is selected from among these detection sensors depending on the speed of the punching line, the state of the mark, the vibration situation, etc.

As shown in FIG. 8, this detection sensor 76 is connected to a movable rod 8 attached to the machine frame via an air cylinder.
It is fixed to the tip of 1. On the lower side of the tip of the movable rod 81, there is a pair of rotatable rollers 8 with a groove in the center.
The end 21a of the thin metal coil plate 21 marked with a mark is always moved in contact with the groove of the roller 82, and serves as a tracking device for the mark detection sensor 76. It has become. A signal from the detection sensor 75 is then sent to a discharge device 77 disposed downstream of the press 75.

Therefore, the detection sensor 76 detects the mark of the defective portion of the marked coil thin plate at an interval of l■, and the information is sent to the discharge device 77 in which section of the can manufacturing metal coil thin plate 21 the defective portion exists. 1. For example, if the toad pattern shown in FIG. 6 is detected, there is a defect somewhere in the second section of the can-making metal coil thin plate 2I, as shown by diagonal lines in FIG. The punched can lid containing the second section of thin plate (can lids 2.3, 4, 5.6 in the figure) or only the can body is removed by a discharge device 77 as shown by the arrow. .

Even if a mark is attached to a product, products in categories other than defective parts can be continued to be transported and taken out as non-defective products.

This embodiment is for punching out can lids or can bodies from coiled sheet metal and removing the punched product if it contains defective areas, or for cutting lines with marked coil detection sensors. It is also possible to cut the sheet into sheets of a predetermined length, remove the sheet including the defective area indicated by diagonal lines in FIG. 6, and punch out a can lid or the like from a normal sheet without any defects.

〔Effect of the invention〕

As explained above, according to the present invention, the dot marks made by the injector are safe and approved by the FDA in terms of food hygiene, and the dot marks made by inkjet dots mark the edges of thin metal coil plates for can manufacturing. Since it is attached to the edge, if the object punched from a thin plate is a can lid, it is located under the rubber that tightens the can lid.
In the case of a can body, since it is attached at a position that enters the seam part of the flange, it is possible to indicate a defective part without affecting the contents at all.

In addition, since defects are displayed for each section in the width direction of the metal coil thin sheet for can manufacturing, only products such as can lids that include defective portions on the thin sheet can be removed, significantly improving yield. .

The injection device does not contact the thin plate, does not deform the thin plate, and can mark defective parts at high speed and reliably.

[Brief explanation of the drawing]

1st t-371 is a process diagram showing the method for indicating defects in metal coil thin plates for can manufacturing according to the present invention. FIG. 2 is a block diagram of an inkjet device and a follow-up device. FIG. 3 is a perspective view of an inkjet device and a follow-up device, and FIGS. 4 to 6 are explanatory diagrams of a dot pattern applied to an edge portion of a metal coil thin plate for can manufacturing. FIG. 7 is a process showing a punching line of the present invention] 4. FIG. 8 is a perspective view of a mark detection sensor device. FIG. 9 is a diagram Tj1 of the theory of defective product exclusion in the case of can lid punching. 1----11111 Metal coil thin plate for can manufacturing 7---
---Flaw inspection equipment! (Defect Inspection System M) 8---------
Inkjet device 51, 52-111 mark

Claims (4)

[Claims] (1) A defect inspection device such as a flaw inspection device is installed on the conveyance line of the thin metal coil sheet for can making, and based on the defect detection signal of this inspection device, the defective parts existing in the thin metal coil sheet for can making are detected. A method for displaying defects in a metal coil thin plate for can manufacturing, characterized in that a mark to be displayed is placed on the edge of the thin plate in the form of a dot pattern using an inkjet device. (2) The dot pattern mark made by the inkjet device is activated by the detection signal of the defect inspection device,
Synchronized with the conveyance line speed of metal coil thin plate for can manufacturing,
At the edge part of the metal coil thin plate for can making, 10 minutes from the edge.
2. A method for indicating defects in a metal coil thin plate for can manufacturing according to claim 1, characterized in that a mark is placed at a position within mm. (3) The above-mentioned defect inspection device has a function of detecting divisions in the width direction of thin metal coil sheets for can manufacturing, and marks marks with information on classification of defective parts in the width direction of thin metal coil sheets for can manufacturing. A method for indicating defects in a thin metal coil sheet for can manufacturing according to claim 1, characterized in that the defect is attached to an edge portion of the thin metal coil sheet for can manufacturing. (4) A defect inspection device such as a flaw inspection device is installed on the conveyance line of the thin metal coil sheet for can manufacturing, and based on the defect detection signal of this inspection device, the defective portions existing in the thin metal coil sheet for can manufacturing are detected. The mark to be displayed is placed in the form of a dot pattern on the edge of the thin plate using an inkjet device, and the marked metal coil thin plate for can manufacturing is then marked at the defective portion by a mark detection device on the punching or cutting line. 1. A method for discharging a defective part of a metal coil thin sheet for can manufacturing, comprising detecting a defective area based on a pattern of marks, and removing a thin plate or punched product containing the defective area.