JP2008064579A - OVD inspection apparatus and OVD inspection method - Google Patents

Abstract

[PROBLEMS] To stably check the quality of OVD without being affected by the pressure trace of OVD applied to the base material, the corrugation of the base material, or the flutter or waviness of the base material during conveyance, and relatively inexpensive. Provide an OVD inspection apparatus and an OVD inspection method.
An OVD inspection apparatus is an apparatus for inspecting an OVD application state at least in a base material provided with OVD on a part of the base material, and transporting means for transporting the base material provided with OVD. Irradiating means for irradiating the OVD with laser light, receiving means for receiving a reflected wave reflected from the OVD with respect to the laser light irradiated from the irradiating means, and converting it into a signal; and a signal converted by the receiving means And identification means for comparing and determining with a predetermined threshold value.
[Selection] Figure 1

Description

  In the present invention, an optically variable device (hereinafter referred to as “OVD”) applied to a substrate is detected by a sensor, and the OVD quality (presence / absence of OVD, misalignment or defect) and the number of OVDs are inspected. It relates to the device.

  OVD is a metal foil deposited on a relief diffraction grating and has a unique optical change function such as the appearance of a stereoscopic image and color shift. In recent years, banknotes, cash vouchers, gift certificates, cash cards In addition, valuable products such as credit cards have been given OVD for the purpose of enhancing the effect of preventing forgery. Among these valuable products, as a more advanced anti-counterfeiting technology, OVD is a complex structure of a plurality of fine diffraction gratings called multiple diffraction gratings, and the wavelength of light diffracted depends on the incident angle. Some that incorporate multiple symbols are also used.

The manufacture of these valuable products with OVD is done by first printing patterns and letters on a substrate such as paper or plastic sheet, and then transferring or crimping the sheet type, patch type, or thread type OVD. In many cases, a foil or OVD sheet is applied to a substrate such as a card or paper.
As a method of transferring or pressure-bonding OVD to a substrate, generally, an OVD sheet or film having an OVD layer formed is disposed between a heated metal stamp and the substrate, and the OVD sheet is stamped. Instead of a hot stamping method that presses against a substrate or a heated stamp, a roll transfer method that uses a heated roll is used.

Since OVD is an element that guarantees that the valuable product is genuine, the OVD attached to the valuable product must not be defective. However, when the OVD is transferred or pressure-bonded to the substrate in the manufacturing process, Depending on the flickering of the material, poor adjustment of the machine, etc., transfer or pressure bonding conditions, etc., OVD is not given to the base material, even if OVD is given, it is not given at an appropriate position, appropriate In some cases, a valuable product having a defect such as missing or chipped OVD is generated although it is given to the position.
Therefore, it is indispensable to guarantee the quality by inspecting all the OVD states assigned to the valuable products.

  In the past, these inspections depended on human visual inspections, but quality standards varied due to differences in acceptance criteria depending on the inspector. In addition, since a human inspection method requires a lot of inspection personnel and inspection time and is inefficient, a mechanical inspection method that does not depend on humans has been required.

  In order to solve these problems, many apparatuses for inspecting surface shape defects have been developed, and as a conventional quality inspection apparatus, an OVD of a product having a uniform and flat surface typified by a card substrate is used. There is a “card surface defect inspection device” for inspection (see, for example, Patent Document 1).

  Another method is to irradiate light on a region on the line over the conveyance width of the inspection object including the OVD layer at a predetermined incident angle, pick up an OVD reproduction image recorded on the OVD layer, and pick up the picked up OVD reproduction image. There is a “quality inspection device” that inspects the quality of the OVD layer by the determination means based on the light intensity distribution (see, for example, Patent Document 2).

  In the OVD foil inspection apparatus and inspection method previously filed by the present applicant, after the OVD is applied to the base material, the re-rolled foil obtained by rewinding the OVD carrier film is irradiated with light. There is a method for inspecting whether or not OVD has been reliably applied based on the presence or absence of the OVD foil remaining on the carrier film as compared with the regular optical information based on the optical information obtained by 3).

  In addition, based on the reflection characteristics of OVD, the present applicant is equipped with a filter that irradiates a region to which OVD is applied with an infrared ray or a light source containing infrared rays, blocks visible light in the visible light reflection region, and transmits infrared rays. An application has been filed for a method in which an image is read by an image input means and the OVD application state is checked by comparison with reference data (see, for example, Patent Document 4).

JP-A-2-248845 Japanese Patent No. 3339426 Japanese Patent Application No. 2006-25194 Japanese Patent Application No. 2004-259785

However, the invention described in Patent Document 1 is for inspecting the surface of a highly rigid substrate that is difficult to flutter during conveyance, and has low rigidity like a substrate, paper, or film that imparts OVD, It is difficult to accurately inspect the OVD applied to a substrate that is likely to flutter during transport. Also, due to the structure of the apparatus, when the inspection section is provided on the plate cylinder and optically inspected, the OVD is irregularly reflected. Therefore, a stable inspection could not be performed.
Further, Patent Document 1 is an inspection of a case where one OVD is applied to one base material, and is not an inspection of a case where a plurality of OVDs are applied to a single base material conveyed at high speed.

  Further, in the invention described in Patent Document 2, quality control is performed to prevent the OVD reproduction image from being greatly changed due to the flickering of the sheet to which the OVD has been added, so that the inspection cannot be performed. Although a device is provided, if a laser sensor is placed perpendicular to the substrate transport direction as a condition for inspecting OVD applied to a low-rigidity substrate under high-temperature and high-pressure conditions using an application machine, etc. Reflection of the laser light irradiated to the OVD due to a slight dent (pressure trace) generated in the OVD application portion due to pressurization by the surface, and poor substrate surface conditions such as undulation generated on the substrate itself due to high temperature and pressure Since the amount of light was not constant (diffuse reflection), it was not possible to perform an accurate OVD inspection.

This is because OVD is completely bonded to the base material, and is performed under a high-temperature and high-pressure condition by an applicator or the like. Because the surface layer of the base material is slightly deformed, such as the corrugation of the base material caused by the light, it is stable even when light is applied to the base material at a specific angle and the reflected light is photographed with a camera. The reflection image data cannot be obtained.
In particular, when the base material is paper, it tends to be deformed at the time of application, and thus the inspection accuracy in the above-described inspection method tends to be low.

  When inspecting an OVD in which a plurality of rows and a plurality of rows (for example, 4 columns × 5 columns = 20 in total) OVDs are inspected on a single sheet, In addition to the corrugation of the base material, the fluttering and waviness of the paper being conveyed are affected, and the reflected light quantity of the laser light irradiated to the OVD is not constant, so the OVD inspection accuracy has not been improved.

  Moreover, about the patent document 3 which this applicant applied for earlier, it is supposed that the state of OVD on a base material was test | inspected by inspecting the carrier film after providing OVD. The OVD itself applied on the substrate was not inspected.

  In addition, Patent Document 4 previously filed by the applicant of the present application is for inspecting OVD on an actual base material. However, it is necessary to irradiate infrared rays, and image processing can be performed on the irradiated light. Since this is necessary, the apparatus for inspection becomes slightly expensive.

  The present invention has been made in order to solve the above-described problems, and is not affected by the pressure trace of the OVD, the corrugation of the base material, or the fluttering or waviness of the base material during conveyance, and stable OVD quality. An object of the present invention is to provide a relatively inexpensive OVD inspection apparatus that enables inspection.

  In addition, the present invention provides a state in which the OVD applied on the substrate (whether or not OVD is present) by arranging a line type laser sensor on the OVD applied on the substrate in parallel with the conveyance direction of the substrate. OVD position, OVD deficiency, and number of OVDs).

  The present invention is an apparatus for inspecting the OVD application state in at least a part of the base material to which OVD is applied, the transport means for transporting the base material to which OVD is applied, and OVD Irradiating means for irradiating laser light, receiving means for receiving a reflected wave reflected from the OVD with respect to the laser light irradiated from the irradiating means, converting it to a signal, a signal converted by the receiving means, and a predetermined threshold value This is an OVD inspection apparatus comprising identification means for comparing and judging.

  In the present invention, when there are a plurality of rows of OVDs parallel to the transport direction transported by the transport unit, a plurality of irradiation units are arranged in parallel with the transport direction corresponding to the OVD. Inspection equipment.

  In addition, the present invention is an OVD inspection apparatus in which the identification unit compares and determines the presence / absence, shape, application position, and / or quantity of OVD.

  Further, the present invention is a method for inspecting the OVD application state in at least a part of the base material provided with OVD, and transporting the base material provided with OVD, on the base material The OVD is irradiated with laser light, the reflected wave reflected from the OVD is received with respect to the irradiated laser light, the received reflected wave is converted into a signal, and the converted signal is compared with a predetermined threshold. This is an OVD inspection method.

  In the present invention, the predetermined threshold value is a value using a difference between a reflected light amount when the OVD is irradiated with laser light and a reflected light amount when the substrate is irradiated with laser light. This is an OVD inspection method.

  Also, by comparing the amount of reflected light when the OVD is irradiated with laser light and a predetermined threshold value, the presence or absence of application of the OVD on the substrate, the shape of the OVD and / or the application position of the OVD are determined, And / or an OVD inspection method that counts the number of OVDs based on the number of times a laser beam is received within a predetermined time.

  According to the present invention, regardless of the number of OVDs applied to the base material, it is not affected by the surface state of the base material (OVD pressure trace) or the surface vibration of the base material during transport (fluttering, etc.). The state of OVD applied on the substrate (presence / absence of OVD, OVD position, OVD deficiency) can be inspected, and the number of OVD applied on the substrate can be accurately counted. Is possible.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  The OVD inspection apparatus 1 according to the present invention includes a transport means 3 for transporting a substrate provided with OVD, an irradiation means 4 for irradiating laser light, and a receiving means for receiving a reflected wave reflected from the OVD 2 and converting it into a signal. 7 and an identification unit 8 for comparing and determining a signal obtained by the receiving unit 7 with a predetermined threshold value, and an OVD applied to the base material is an inspection target.

  FIG. 1 is a schematic side view showing the configuration of the OVD inspection apparatus of the present invention.

  As shown in FIG. 1, the base material 1 to which OVD is applied is transported by the transport means 3, the laser light 5 is irradiated from the irradiation means 4, and the laser light 6 reflected by the OVD 2 applied on the base material 1 is reflected. The reception unit 7 is configured to receive the signal, and the signal obtained by the reception unit 7 is configured to be compared with a certain threshold value by the identification unit 8.

  The laser beam 4 irradiating the base material 1 and the OVD 2 is configured to be arranged corresponding to the OVD on the transport of the OVD 2 applied to the base material 1. Corresponding to this OVD is that when a plurality of OVDs are applied to a base material to be inspected or a plurality of base materials to which one OVD is applied to one product are arranged (hereinafter referred to as “multi-face plate”). In this case, a plurality of substrates are arranged in parallel to the direction in which the substrate is conveyed. For example, as shown in FIG. 2, when a plurality of OVDs (2a, 2b, 2c, 2d) provided on the substrate 1 are to be inspected, the substrate 1 is mechanically moved in the transport direction (arrow direction). Since the OVD (2a, 2b, 2c, 2d) provided on the base material also moves in the direction of the arrow, the irradiation means 4 has the OVD (2a, 2b, 2c) provided on the base material. 2d) is provided in parallel with the conveyance direction of the base material at the upper part (four places) of the position (orbit) to which 2d) moves.

  The reason why the substrate is arranged in parallel to the conveyance direction of the substrate is not affected by the OVD irregular reflection, and the reflected light quantity of the laser beam irradiated to the OVD is stabilized, so that the OVD inspection accuracy is improved. It is in. Therefore, even when inspecting OVD applied to a substrate that is low in rigidity, such as paper or film, and easily flutters during transportation, pressure marks and substrates generated on the substrate during OVD application It is possible to perform a highly accurate inspection without being affected by slight deformation such as undulation of the OVD, and OVD irregular reflection due to fluttering and waviness of the substrate being conveyed.

  Similarly, it is desirable that the receiving means 7 for receiving the laser beam 6 irradiated and reflected on the OVD 2 is also arranged in parallel with the direction in which it is conveyed.

  Visible semiconductor laser light is most preferable as the laser light applied to the OVD 2, but line-type laser light may be used.

  Moreover, what is necessary is just to adjust suitably the installation position of an irradiation means and a receiving means with the provision position and provision number of OVD provided to the base material.

Next, a method of detecting the OVD applied to the base material with laser light will be described with reference to FIG.
FIG. 3 is a schematic diagram for inspecting the OVD 2 applied to the substrate 1.
First, the base material 1 moves in the conveyance direction (arrow direction), and detects the laser beam 6 reflected with respect to the laser beam 5 irradiated to the OVD 2 at the position A (FIG. 3A). Next, the base material 1 further moves in the transport direction (arrow direction), and detects the laser beam 6 reflected at the position B on the OVD 2 (FIG. 3B). Then, the substrate 1 further moves in the direction of the arrow, and the laser beam 6 reflected at the position C is detected (FIG. 3C). In this way, the inspection is performed by repeatedly performing the steps shown in FIGS.

  At this time, FIG. 4 shows the relationship between the intensity of the reflected laser light and the detection position with the amount of reflected light. When the laser light irradiates OVD (FIG. 3B), a large amount of reflected light can be obtained, and therefore generally higher than the amount of reflected light 8 reflected when the laser light irradiates the substrate (FIGS. 3A and C). Value.

  A threshold is used as a criterion for detecting OVD2. The threshold value 10 can be arbitrarily determined in the setting in the inspection, but in FIG. 4, when the OVD 2 is irradiated with laser light, the amount of reflected laser light reflected and returned to the substrate 1 is the same as that of the OVD 2. A laser beam is used that uses a value obtained by halving the difference in the reflected light amount of the laser beam that is reflected and reflected back.

  Here, the presence / absence inspection of OVD in the OVD inspection apparatus of the present invention will be described with reference to FIG. When the laser beam 5 irradiated from the irradiation unit 4 scans the OVD portion applied to the substrate 1 (FIG. 5A), the laser beam 6 reflected by the reception unit 7 is received. Then, the intensity of the laser beam 6 received by the receiving unit 6 is compared with a threshold value set in advance by the identifying unit 8, and OVD2 is applied on the substrate 1 if the intensity of the laser beam is greater than or equal to the threshold value. If the laser beam is below the threshold (FIG. 5 (d)), it is determined that OVD2 is not applied on the substrate 1.

  As described above, the presence / absence of OVD applied on the substrate can be detected from the relationship between the amount of reflected laser light and the threshold value.

  The numerical value of the reflected light amount of the OVD 2 can be inspected more stably if the sensitivity is set to the maximum value in the angle adjustment when the sensor is installed.

  Although the OVD presence / absence inspection has been described above, the size of the OVD that is normally given in the above-described identification unit 8 is converted into time length, and the OVD given on the substrate to be inspected is in a certain direction. It is also possible to detect a shape defect in which a part of the OVD is missing by comparing the time length of the received laser light.

  For example, as shown in FIG. 6A, when the OVD 2 applied on the substrate 1 has a normal size, a peak of the reflected light amount graph appears as shown in FIG. ), When the OVD2 is smaller than the normal size, the reflected light amount graph has a shorter length in the moving direction of the reflected light amount exceeding the threshold 10 ′ as shown in FIG. It can be seen from FIG. 6C that an OVD having a shorter moving direction than the OVD applied on the substrate is applied.

  Since OVD on substrates having different sizes can be detected from this, it is possible to determine that a part of the OVD applied on the substrate is missing.

  Furthermore, by setting the timing relating to the position of the OVD on the base material in advance in the identification means, it is possible to inspect the application position as to whether or not the OVD is applied to the normal position on the base material, and within a certain time. The number of OVDs provided on the substrate can be counted according to the number of laser beams received. In addition, the faster the response speed within a certain time by the sensor, the greater the number of detections, thereby improving the inspection accuracy. (The response speed used this time is 80 μsec.)

Embodiments relating to the present invention will be described based on examples with reference to the drawings, but are not limited thereto as long as they are within the scope of the claims.

(Example 1)
An application of the OVD inspection apparatus of the present invention to a printing machine will be described as an example. As shown in FIG. 7, the basic configuration of the printing machine A according to the present invention includes a paper feed unit B, a printing unit C, a paper discharge unit D, an OVD inspection unit E, and a determination control unit F. The sheet feeding unit B conveys the sheets b stacked on the sheet stacking unit a to the printing unit C one by one along the conveying plate c. Next, the printing unit C passes the paper b fed from the paper feeding unit B one by one between the numbering cylinder d and the impression cylinder e, and the letter ring provided in the numbering cylinder d. The number is printed at a predetermined position on the paper b by f.

Further, the paper discharge unit D transports the paper b printed by the printing unit C by the gripper h of the transport chain g, and transports the paper b to the paper discharge pile i or the paper discharge pile i ′ one by one. At this time, the discharge pile i may be a mechanism for stacking normal sheets b, and the discharge pile i ′ may be a mechanism for stacking abnormal sheets b.
Further, the OVD inspection unit F irradiates the OVD applied to the paper b conveyed one by one from the paper stacking unit a of the paper feeding unit B with a laser beam by the irradiation means j, detects the reflected light amount, Perform OVD inspection.

  Next, the OVD inspection unit F will be described with reference to FIG. 8, and the sheet b transported by the sheet b on the transport plate c of the sheet feeding unit B contacts the front contact plate k and the lateral contact plate m. Then, positioning is performed, and the sheet b is sent to the number printing section C. The laser receiver / projector j is provided on the upper part of the transport plate c, and is set in the same direction as the transport direction on the transport of the OVD 2 applied to the paper b. The distance between the sensor and the substrate 1 varies depending on the size of the OVD 2, and the height is adjusted so that the length of the laser light emitted from the line type laser sensor is longer than the OVD 2. For example, when the size of the OVD is about 20 mm square, the distance between the sensor and the OVD is preferably about 50 to 100 mm between the laser and the paper. In addition, it is desirable that the attachment position of the laser receiver / projector j is appropriately adjusted according to the application location, the application position, and the application number of the OVD 2 applied to the paper.

  The determination control unit F is sent with the amount of reflected laser light received by the light receiving device j of the inspection unit E, and determines whether or not the OVD 2 is normally applied to the paper b. The normality determination is performed based on the amount of reflected laser light as described above. For example, normal paper (hereinafter referred to as “normal paper”) is exceeded when a certain threshold value is exceeded, and abnormal paper (hereinafter “lossy paper” is referred to when it is not exceeded. Or a fixed laser reflection width, and if the laser reflection width is longer, the paper may be inspected as normal paper, and if shorter, the paper may be inspected as waste paper. When the identification unit F determines that the paper is normal, the printing unit C performs printing, and the paper b is conveyed to the paper discharge pile i of the paper discharge unit D, but the determination control unit F determines that the paper is broken. Alternatively, the printing unit C may perform number printing, and a function of conveying the paper b to the paper discharge pile i ′ dedicated to the waste paper of the paper discharge unit D may be used. Further, when the judgment control unit F determines that the paper is damaged, at the timing when the waste paper passes through the printing unit C, the gap between the cylinder d and the impression cylinder e is opened and printing is not performed. A function of conveying the paper b to the dedicated pile i ′ may be used.

  In the first embodiment, a sheet is used as the base material, but roll paper or the like on which the base material is wound is also applicable.

  In the first embodiment, the OVD inspection apparatus is mounted on the printing press. However, the present invention is not limited to the printing press and can be applied to any form.

(Example 2)
In the second embodiment, a printing machine A ′ different from that of the first embodiment will be described with reference to FIG. 9, but a paper feeding unit B ′, a printing unit C ′, a paper discharge unit D ′, an OVD inspection unit E ′, and a determination. Since the control unit F ′ performs the same functions and methods as those in the first embodiment, the description thereof is omitted, and only different parts and methods are described. A feature of the printing machine A ′ is that it has a function of inspecting the printing area of the paper b ′ to which printing or OVD has already been applied. Specifically, the printing inspection unit G is provided between the paper feeding unit B ′ and the printing unit C ′, and the paper b ′ is sucked and adhered by the inspection cylinder o, and the print area of the paper b ′ is input by the optical camera p. After that, the sheet is conveyed to the printing unit B ′ via the transfer cylinder q.

  The OVD inspection unit E ′ is located above the inspection cylinder o, inspects the print area with the optical camera p, and then performs OVD inspection with the laser receiver / projector j ′. Information obtained by the optical camera p and the laser receiver / jumper j ′ is collectively determined by the determination control unit F ′, and when it is determined to be a normal sheet, the information is printed by the printing unit C ′ and the pile i of the sheet discharge unit D ′ is printed. However, if the determination control unit F ′ determines that the paper is damaged, the print i is printed by the printing unit C ′, and the pile i ′ dedicated to the paper discharge of the paper discharge unit D ′. A function of conveying the paper b ′ to ″ may be used. Further, when the judgment control unit F ′ determines that the paper is broken, the gap between the impression cylinder e ′ and the numbering cylinder d ′ is opened at the timing when the broken paper passes the number printing unit C ′, and printing is performed without printing. A function of conveying the paper b ′ to the pile i ′ ″ dedicated to the waste paper of the paper part D ′ may be used. The laser receiver / jumper j 'may be provided before inspecting the optical camera p, or two inspection cylinders may be provided in order to inspect the front and back of the printed matter.

OVD inspection device outline side view Laser light irradiation position overview Schematic for inspecting OVD2 applied to substrate It is a figure which shows a laser reflective state. OVD presence / absence detection chart OVD shape abnormality detection diagram Number printing machine with OVD inspection device It is a detection figure of OVD. Number printing machine with OVD inspection device

Explanation of symbols

1 Base material 2 OVD
3 Conveying means 4 Irradiating means 5 Irradiated laser light 6 Reflected laser light 7 Receiving means 8 Identification means 9 Reflected light quantity 10 Threshold 11 Setting timings A, A ′ number printing machine B, B ′ paper feeding section C, C ′ number printing section D , D ′ paper discharge unit E, E ′ OVD inspection unit F, F ′ identification unit (identification means)
G Print inspection part a, a ′ Paper stacking part b, b ′ Paper c, c ′ Conveying plate d, d ′ Number cylinder e, e ′ Impression cylinder f, f ′ Ring ring g, g ′ Conveying chain h, h ′ Gripper i, i ′, i ″, i ′ ″ Paper discharge pile j, j ′ Laser projector k Front contact plate m Horizontal contact plate p Optical camera q

Claims (6)

An apparatus for inspecting the application state of the OVD in at least a part of the substrate provided with OVD, a conveying means for conveying the substrate to which the OVD is applied, and a laser for the OVD An irradiating means for irradiating light, a receiving means for receiving a reflected wave reflected from the OVD with respect to the laser light emitted from the irradiating means, and converting it into a signal; a signal converted by the receiving means; An OVD inspection apparatus comprising identification means for comparing and determining a threshold value. The irradiating means, when there are a plurality of rows of the OVD parallel to the transport direction transported by the transport means, a plurality of the OVDs are arranged in parallel with the transport direction corresponding to the OVD. 1. The OVD inspection apparatus according to 1. 3. The OVD inspection apparatus according to claim 1, wherein the identification unit compares and determines the presence / absence, shape, application position, and / or quantity of the OVD. A method of inspecting the application state of the OVD in a substrate in which OVD is applied to at least a part of the substrate, wherein the substrate to which the OVD is applied is transported to the OVD on the substrate. A laser beam is irradiated to the received laser beam, a reflected wave reflected from the OVD is received with respect to the irradiated laser beam, the received reflected wave is converted into a signal, the converted signal, and a predetermined threshold value are set. OVD inspection method for comparison determination. The predetermined threshold value is a value using a difference between a reflected light amount when the laser light is irradiated on the OVD and a reflected light amount when the laser light is irradiated on the substrate. The OVD inspection method according to claim 4. By comparing the amount of reflected light when the OVD is irradiated with the laser light and the predetermined threshold value, the presence / absence of application of the OVD on the substrate, the shape of the OVD, and / or the position of application of the OVD is determined. 6. The OVD inspection method according to claim 4 or 5, wherein the number of OVDs is counted based on the number of times the laser beam is received within a predetermined time.

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