JP2000292368A - Quality inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve work efficiency of quality inspection. SOLUTION: In the middle of conveyance of a test object, for example, a paper sheet printed matter 153, the front and back printed surfaces thereof are illuminated respectively by illumination light sources 14, 15 and 24, 25. Each illuminated surface of the paper sheet printed matter 153 are imaged respectively by imaging cameras. Existence of a defect is determined by a determination means 36 based on image data. The existence of a defect on both the front and back surfaces can be inspected during one-time conveyance of the paper sheet printed matter 153.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an object to be inspected, for example, a sheet-fed printed matter in which a plurality of packaging box structures are printed as a set on the front and back sides, and a plurality of packaging box structures are repeated as a set. In the process of transporting a long printed material or the like printed on the front and back for paper ejection, that is, in-line, or in the process of transporting the printed material or the like for inspection only, that is, off-line, the surface to be inspected. Printing errors on the printing surface,
The present invention relates to a quality inspection device used for detecting the presence or absence of a defect such as dirt.

[0002]

2. Description of the Related Art In recent years, in addition to printing a product name, a manufacturer / seller display, and the like on the surface of a packaging box for storing articles,
Attempts have been made to print explanations on handling etc. on the packaging box instead of putting explanations on handling etc. in the packaging box. In order to obtain the packaging box, for example, as shown in FIG. 7, a plurality of packaging box components 152 are printed as a set on a surface of a sheet 151 made of a relatively thick material. And
As shown in FIG. 8, a plurality of packaging box structures 152 corresponding to the front surface, such as a desired description, are printed as a set on the back surface of the sheet 151 (for easy understanding, FIGS. 7 and 8). In, the planned punching outline is indicated by a dashed-dotted line, and the planned fold line and perforated cutout line are indicated by a dashed-dotted line.) Then, the packaging box structure 152 can be punched from the sheet-fed printed material 153 along the predetermined outline and assembled into a packaging box.

In the above-described sheet-fed printed material 153, it is necessary to detect various defects such as printing stains and adhesion of foreign substances. Traditionally, to detect such defects,
In general, first, printing is performed on the back surface of the sheet 151, and while the sheet 151 is conveyed in a straight line at the paper discharge unit, the back surface is inspected using an inspection device equipped with an imaging camera, and dried. Then, a good product and a defective product are determined. Next, the non-defective sheet 151 is reversed and printed on its surface, and the surface is inspected using the inspection device and dried while the printed sheet 153 is transported in a straight line at the paper discharge section. , A good product and a defective product. That is, the printing, inspection, drying, and sorting of the back surface of the sheet 151 and the printing, inspection, drying, and sorting of the front surface of the sheet 151 are repeated twice.

As another conventional example, first, a sheet 151
Is printed on the back side of the sheet, and then printed on the front side of the sheet 151. For example, while the sheet printed matter 153 is being conveyed linearly in the discharge section, the front surface of the sheet printed matter 153 is taken by an imaging camera. Inspection is carried out using an inspection device provided and dried, and is sorted into non-defective products and defective products. Then, as a result of the inspection, the non-defective sheet printed matter 153 is conveyed by a conveyance device dedicated to inspection, and during the conveyance, the sheet printed matter 153 is conveyed.
Is inspected in the same manner as above, and is sorted into non-defective products and defective products.

[0005] As still another example of the prior art, while a sheet-fed printed matter 153 is being conveyed by a conveyer dedicated to inspection, first,
A method of inspecting and sorting either the front side or the back side, inverting the non-defective sheet-fed printed matter 153, and inspecting and sorting the remaining surface in the course of being conveyed again by the inspection-specific conveying device is also adopted. ing.

[0006]

However, in the above-mentioned conventional method, the first method requires a great deal of time to print and inspect the sheet 151. The second method can greatly reduce the time required for printing the sheet 151, but requires a transport device (offline) dedicated to inspection,
This transport device is expensive because it has the same configuration as the printing device (in-line). In addition, sheet-fed printed matter 1
After inspecting any one of the surfaces 53, it is necessary to inspect the remaining surface in the course of inverting and transporting the sheet-fed printed matter 153. That is, an extra transport operation in which the sheet-fed printed matter 153 is turned upside down is required, so that the quality inspection operation efficiency is inferior. Also, the third method becomes expensive and inferior in quality inspection work efficiency as in the second method.

An object of the present invention is to solve the conventional problems as described above, and inspect both the front and back sides of an object to be inspected once, whether it is in-line or off-line. Accordingly, it is an object of the present invention to provide a quality inspection apparatus capable of improving the work efficiency of the quality inspection.

[0008]

In order to solve the above-mentioned problems, a quality inspection apparatus according to the present invention illuminates first and second inspection surfaces of the inspection object while the inspection object is being conveyed. Means, imaging means for imaging each of the inspection surfaces illuminated by the illumination means, and determination means for determining the presence or absence of a defect on each inspection surface based on the output from each of the imaging means. It is provided.

[0009] In the above arrangement, the imaging means for imaging the second inspection surface of the inspection object can be arranged below the conveyed inspection object.

[0010] An imaging means for imaging the second inspection surface of the inspection object includes an imaging unit and a cover for covering the imaging unit so as to image the second inspection surface. An imaging camera can be used as the imaging unit, or an imaging camera and a mirror that reflects the second inspection surface can be used for the imaging camera. A light transmitting cover can be used as the cover, and the light transmitting cover is preferably set to have an angle with respect to a horizontal plane. In addition, an optical system box that houses an imaging unit may be used as the cover, and the second inspection surface may be imaged by the imaging unit through a light transmission plate of the optical system box. It is preferable to set the angle with respect to the horizontal plane. Further, the illumination means can be housed in the optical system box. When the optical system box is used as described above, it is preferable that the cooling medium is circulated through the optical system box.

Preferably, the illuminating means on the second inspection surface is supported so as to be able to be taken out to the side, or the illuminating means and imaging means for the second inspection surface are supported so as to be able to be taken out to the side. .

According to the quality inspection apparatus of the present invention configured as described above, the first inspected surface and the second inspected surface of the inspected object are respectively conveyed during the transport of the inspected object once. An image is taken by the imaging means, and the presence / absence of a defect on the first inspection surface and the second inspection surface is determined by the determination means based on the imaging result.
Even if it is off-line, it is possible to inspect both the front and back while transporting the inspection object once.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment of the present invention will be described. FIG. 1 is a schematic side view of a part of the quality inspection apparatus according to the first embodiment of the present invention applied to a printing apparatus (in-line) for sheet-fed prints, and FIG. FIG. 3 is a partially cutaway plan view of the inspection unit, and FIG. 4 is an explanatory view of a state in which an illumination light source, an imaging unit, and the like are taken out to the side in the inspection unit.

In FIG. 1, reference numerals 1, 2, and 3 denote a plate cylinder, a blanket cylinder, and an impression cylinder, respectively, which constitute an offset printing press. On the upstream side of the plate cylinder 1, blanket cylinder 2, and impression cylinder 3, a similar plate cylinder, blanket cylinder, impression cylinder, and a printing ink drying device (all not shown) are provided. The sheet 151 (see FIGS. 7 and 8) fed between the impression cylinder and the blanket cylinder (not shown) is applied to the plate surface of the plate cylinder on the second surface (the back surface in the present embodiment). UV dried ink is transferred and printed via a blanket cylinder, and then UV (not shown)
The first printing surface is dried by an ink drying device provided with an (ultraviolet) irradiation lamp, an IR (infrared) lamp, and the like. Subsequently, the sheet 151 is turned over and the impression cylinder 3 is turned over.
The ultraviolet-drying type ink sent between the printing drum 1 and the printing drum 1 and transferred to the plate surface of the printing drum 1 is transferred via the blanket cylinder 2 to the first surface (the front surface in this embodiment) of the sheet 151. Is printed.

Reference numeral 4 denotes conveying means, and a pair of right and left chains 5
Is endlessly hung on sprockets 6 and 7, and one sprocket 6 is driven clockwise in the figure by a motor (not shown), and the sprocket 6 is driven to drive the chain 5.
Can run in the direction of the arrow. A gripping means 8 including a rod, gripping claws, and the like is attached between the chains 5,
The gripping means 8 grips the leading end of the sheet-fed printed material 153 discharged from between the impression cylinder 3 and the blanket cylinder 2 after printing on the front and back surfaces on the sprocket 6 and moves the chain 5,
It is transported in the direction of the arrow. 9 is a sheet-fed printed material 15 to be conveyed
3 is a plate-like guide member for holding the horizontal position of the guide member 3. Numeral 10 is a drying device for drying the ultraviolet-drying type ink on the first printing surface of the sheet-fed printed material 153 to be conveyed.
An (ultraviolet) irradiation lamp or an IR (infrared) lamp (both not shown) are covered by a cover 11. 1
Reference numeral 2 denotes a receiving box for the defective sheet printed matter 153, and reference numeral 13 denotes a receiving box for the non-defective sheet printed matter 153. When the gripping means 8 is released, the sheet printed matter 153 is selectively dropped and stored.

Reference numerals 14 and 15 denote between the sprocket 6 and the ink drying device 10, that is, a front position where the sheet-fed printed matter 153 is linearly conveyed to the ink drying apparatus 10 in a horizontal state. Illuminating light sources for the bright field and the dark field, which reflect and illuminate the twelfth printing surface (surface), which is the surface to be inspected. Then, the sheet 153 is sequentially and substantially uniformly illuminated over almost the entire width of the conveyed sheet-like printed matter 153. Reference numeral 16 denotes an image pickup unit that picks up an image of the first printing surface of the sheet-fed printed matter 153 illuminated by the illumination light emitted from the illumination light sources 14 and 15 from above. A camera 16 such as a CCD line sensor for taking an image using the lens 16a is used, and is housed in an optical system box (not shown) that can be opened and closed as needed. One or a plurality of imaging cameras 16 (three in FIG. 3) are arranged in the width direction of the single-sheet printed material 153 and are conveyed.
The image is sequentially taken over almost the entire width of 53.

A large number of intake holes 17 (see FIG. 2) are vertically and horizontally arranged in a lower portion of the imaging camera 16 in the guide member 9, and a sheet print 153 conveyed by the conveying means 4 is sucked by a suction source (not shown). The suction camera 17 sucks the air through the air intake hole 17 so that the suction member 17 is attached to the upper guide surface of the guide member 9 and the imaging camera 16 is driven.
The sheet-like printed matter 153 picked up by the printer can be conveyed flat so that flapping, warping, and the like do not occur. At this time, the second printing surface (rear surface), which is the downwardly-facing inspection surface of the sheet-fed printed material 153, comes into contact with the upper guide surface of the guide member 9, but this printing surface has already been dried with the printing ink. Therefore, there is no fear of disappearing even if it is slightly rubbed. The guide member 9 has an elongated hole 18 in the width direction at a front position where the sheet-fed printed matter 153 is linearly conveyed to the ink drying device 10 in a horizontal state.

Reference numeral 20 denotes an image pickup means for picking up an image of the second printing surface (back surface) of the sheet-fed printed matter 153 from below, and a front position at which the sheet-fed printed matter 153 is conveyed straight to the ink drying apparatus 10 in a horizontal state. At the lower side of the guide member 9. In the illustrated example, the imaging unit 20 serves as an imaging unit, such as a camera 21 such as a CCD line sensor that captures an image of the second printing surface of the single-sheet print 153 using a telephoto lens 21a, and an imaging camera 21 that captures the second printing surface. An illumination unit having a reflection mirror 22 for reflecting light contained in an optical system box 23 which is a coating body, and having bright-field and dark-field illumination light sources 24 and 25 for reflecting and illuminating the second printing surface on the optical system box 23. 29 is removably housed sideways.

More specifically, as shown in FIGS. 2 to 4, in the optical system box 23, an upright portion 27 is integrally formed on one side of a flat portion 26 with a metal such as iron or aluminum in a communicating state. A lid 28 that can be opened and closed is provided on the upper surface of the flat portion 26, and a transparent light transmission made of glass or the like inclined at an angle to the horizontal direction is provided at an open upper end of the upright portion 27. The plate 30 is mounted so as to be closed. A light transmitting plate 30 is provided in the upper part of the upright portion 27.
, Illumination light sources 24 and 25 for bright field and dark field are arranged. These illumination light sources 24, 25
As an example, a fluorescent lamp is used as the light transmitting plate 30.
Through the hole 18 of the guide member 9 so that the second print surface of the sheet-fed print 153 can be sequentially and substantially uniformly reflected and illuminated over substantially the entire width. Flat part 2
The reflection mirror 22 is provided in the lower part of the upright part 27 in the inside 6, and the imaging camera 21 is provided on the side separated from the upright part 27, and the position can be adjusted by removing the lid 28. ing. One or a plurality of imaging cameras 21 (three in the illustrated example) are used in the width direction of the single-sheet print 153, and the second of the single-sheet prints 153 by the imaging camera 21 via the light transmitting plate 30 and the reflection mirror 22. Can be sequentially imaged over almost the entire printing surface. The end of the flat portion 26 on the side away from the upright portion 27 and the upright portion 27
A supply port 31 and a discharge port 32 for circulating cooling air, which is a cooling medium, are formed at the upper end portion. The supply port 31 and the discharge section 32 are connected to a cooling air supply source (not shown). It is connected.

The lower part of the optical system box 23 is supported by a slide unit 33, and the slide unit 33 is mounted on a mounting base 34 via a linear guide 35. Therefore, the optical system box 23 and the like can be slid in two stages via the linear guide 35 and the slide unit 33 in the direction perpendicular to the transport direction of the sheet-fed printed matter 153 and in the horizontal direction. It is taken out to the side of the member 9 and the like, so that replacement of the illumination light sources 24 and 25, adjustment of the position of the imaging camera 21, and the like can be easily performed. The imaging unit 20 containing the illumination light sources 24 and 25, as shown by a chain line in FIG. 1, guides the sheet-fed printed matter 153 to be dried in a printing ink drying device 10 and then conveyed in an inclined straight line. Can also be placed.

In FIG. 1, reference numeral 36 denotes an imaging camera 16, 2
A determination means for comparing the density levels of the multi-tone image data obtained from the output No. 1 with the reference density levels to determine whether or not there is a defect on the printing surface. And the determination means 3
6, the gripping means 8 is released in correspondence with the defective product receiving box 12 and the good product receiving box 13 as described above.

The operation of the above configuration will be described below. As shown in FIGS. 7 and 8, the sheet-fed printed matter 153 in which the display contents of the plurality of packaging box members 152 are printed on the front and back sides with the ultraviolet-drying ink as described above is obtained from the impression cylinder 3 and the blanket cylinder 2. The gripping means 8 which is ejected and attached to the chain 5 where the leading end of the sheet-fed print 153 is running.
Is held on the sprocket 6 and conveyed on the guide member 9. In the course of this conveyance, first, the sheet-fed printed material 153 is driven by the suction source through the suction hole 17 to illuminate the illumination light source 1.
4, 15 and the lower side of the imaging camera 16 are conveyed flat along the guide surface on the guide member 9, during which the first print surface of the sheet-fed printed material 153 extends from the leading end to the trailing end, and sequentially. The reflected light is illuminated by the illumination light sources 14 and 15, and the reflected illuminated portion is imaged by the imaging camera 16. At the same time, the second printing surface of the sheet-fed printed material 153 extends from the leading end to the trailing end, and is sequentially reflected and illuminated by the illumination light sources 22 and 23.
An image is captured by the imaging camera 21 via the reflection mirror 22. Subsequently, the second printing surface of the sheet-fed print 153 is dried by the ink drying device 10.

In the meantime, the determination means 36 determines the presence or absence of a defect on the first and second printing surfaces of the sheet print 153 based on the image data obtained by the imaging cameras 16 and 21. As an example, a multi-tone area image is created from 256-step multi-tone line image data sequentially output from the imaging cameras 16 and 21, and the density level of each part of the multi-tone area image is determined as a reference image. Is compared with the density levels of the corresponding parts of the 256-tone multi-tone area image, and the presence or absence of a defect is determined based on the allowable value of the density level difference between the corresponding parts of the two images. At this time, as described above, the bright-field illumination light sources 14 and 24, the dark-field illumination light sources 15, 2
By using 5 in combination, it becomes easier to obtain the color component of the color ink and the like, and it is possible to improve the defect detection accuracy. Then, as a result of the determination by the determination means 36,
If the sheet printed matter 153 is good, the sheet printed matter 15
3 is released at the position of the non-defective product receiving box 13, and the non-defective sheet-fed printed matter 153 that has been grasped is dropped into the non-defective product receiving box 13. On the other hand, if the sheet printed matter 153 is defective, the gripping means 8 holding the sheet printed matter 153 is released at the position of the defective article receiving box 12, and the defective sheet printed matter 153 held is removed. It is dropped into the defective product receiving box 12.

The illumination light sources 24 and 25 for reflecting and illuminating the second printing surface, which is the downwardly-facing inspected surface of the sheet-fed printed matter 153, are subjected to the second printing by adhesion of falling dust and the like. It is housed in an optical system box 18 having a light transmitting plate 30 so that the presence or absence of a defect on the surface is not erroneously determined. And these illumination light sources 24, 2
5. Since the imaging camera 21 and the like are arranged in the vicinity of the ink drying device 10, even if a heat dissipation structure is adopted for the optical system box 23, thermal effects cannot be prevented. Therefore, cooling air is supplied from the supply port 31 by driving the cooling air supply source and exhausted from the exhaust port 32 so that the inside of the optical system box 23 does not become hot, and the illumination light source 2
4, 25, the function of the imaging camera 21 can be prevented from being deteriorated or damaged. Further, since the light transmitting plate 30 is inclined, it is possible to prevent the fallen dust and the powder falling from the sheet printed material 153 from collecting on the light transmitting plate 30. Even if dust or the like adheres to the upper portion, since the light transmitting plate 30 is inclined, it can be easily removed by blowing air. Also,
As shown in FIG. 4, the optical system box 23 and the like are transported via the linear guide 35, the slide unit 33 and the like,
By moving the guide member 9 to the side and removing it, the illumination light sources 24 and 25 can be easily removed and replaced by opening and closing the door 28.

As described above, the illumination light sources 24 and 25, the reflection mirror 22, the imaging camera 21 and the like are housed in the optical system box 23, so that the downward first printing surface of the sheet-fed printed matter 153 can be inspected in a narrow space. And the optical system box 23 can be moved to the side, so that the illumination light sources 24 and 25 can be replaced at the side. Suitable to do.

Next, a second embodiment of the present invention will be described. FIG. 5 shows a quality inspection device according to the second embodiment of the present invention, which is a transport device dedicated to inspection of sheet-fed printed matter (offline).
FIG. 6 is an enlarged view showing an inspection unit on the back surface side in the quality inspection apparatus.

A transport device (offline) dedicated to inspection to which the quality inspection device according to the present embodiment is applied is a process from an impression cylinder to a paper discharge section in a printing device (inline) to which the quality inspection device according to the above embodiment is applied. It is configured similarly.

In FIGS. 5 and 6, reference numeral 41 denotes an inspection cylinder;
Is a pressing member that presses against the inspection cylinder 41 that rotates on both side edges of the sheet-fed printed material 153 that is printed on the front and back and that is supplied after being dried, and that prevents it from jumping up. The chain 44 has sprockets 45 and 46
The one sprocket 45 is driven clockwise in the figure via a power transmission mechanism 48 by the driving of a motor 47, and the chain 44 can run in the direction of the arrow by the driving of the sprocket 45. I have. A gripping means 49 including a rod, a gripping claw, and the like is attached between the chains 44, and the front end of the sheet print 153 discharged from the inspection cylinder 41 by the gripping means 49 is sprocket 45.
It is gripped above and transported in the direction of the arrow as the chain 44 travels. Reference numeral 50 denotes a guide member that guides the sheet-fed printed material 153 to be conveyed in a range from the lower outer peripheral portion of the sprocket 45 to the inclined linear portion. The guide member 50 has a number of intake holes 51 like the guide member 9, The sheet-fed printed matter 1 is sucked by suction means (not shown) through these air intake holes 51.
53 is arranged along the guide surface so as not to flutter. 52 is a receiving box for the sheet-fed printed matter 153 of the defective product;
Reference numeral 3 denotes a receiving box for the non-defective sheet-fed printed material 153,
By releasing the sheet 9, the sheet-fed printed matter 153 is selectively dropped and stored.

Reference numerals 54 and 55 denote sheet-fed prints 1 on the inspection cylinder 41.
53 is a bright-field and dark-field illumination light source that reflects and illuminates a first printed surface (front surface), which is an upwardly-facing surface to be inspected, which is pressed by the pressing member 42 in 53, and includes, for example, a fluorescent lamp. The first printing surface of the sheet print 153 is sequentially and uniformly illuminated over substantially the entire width. Each illumination light source 54, 5
5 is supported by frames 56 and 57,
Reference numeral 7 is attached to a machine frame (not shown) so that the position can be adjusted. Reference numeral 58 denotes an imaging unit that captures an image of the first printing surface of the sheet-fed printed material 153 illuminated by the illumination light emitted from the illumination light sources 54 and 55. Similarly, an imaging camera 59 having a telephoto lens 59a is used.
A table or a plurality of sheets in the width direction of the sheet-fed printed matter 153 are housed in the openable and closable optical system box 60, and the front surface (the lower surface)
The first printing surface of the sheet-fed printed material 153 is sequentially imaged over substantially the entire width through a light transmitting plate (not shown). The optical system box 60 is attached to the machine frame so that the position can be adjusted.

Reference numerals 61 and 62 denote illumination light sources for the bright field and the dark field, for example, composed of fluorescent lamps.
Are arranged in the vicinity of the hole 63 formed in the width direction in the slanted linear portion of the sheet-like printed material 153 in the same manner as in the above embodiment.
Is set so that the second printing surface can be sequentially reflected and illuminated uniformly over substantially the entire width. Illumination light source 6
The boxes 1 and 62 are supported by a box 64, and the box 64 is attached to the machine frame so as to be adjustable in position, so that the surface to be inspected can be illuminated through a light transmitting plate (not shown) on the front. The illumination light sources 61 and 62 are replaced by opening and closing a double door 65 formed in a box 64 behind the illumination light sources 61 and 62. Therefore, by bringing the illumination light sources 61 and 62 as close as possible to the sheet-fed printed material 153, even if the space between the guide member 50 and the guide member 50 is exhausted, it can be easily replaced.

Reference numeral 66 denotes an image pickup means for picking up an image of the second printing surface of the sheet-fed printed material 153 from obliquely below the second printing surface.
0. The imaging unit 66 in the illustrated example is a CCD line sensor or the like that uses the telephoto lens 67a to image the second printing surface of the sheet-fed printed material 153 over substantially the entire width in the width direction as an imaging unit, similarly to the above-described embodiment. One,
Alternatively, a plurality of cameras 67 pass through a hole 68 formed in the frame 64 in the width direction of the sheet printing material 153 in the width direction and the illumination light sources 61 and 62, and the second of the sheet printing material 153.
Reflection mirror 69 for reflecting the printing surface of
Are housed in optical system boxes 70 and 71 which are opened and closed by lids (not shown) provided in communication with each other as a cover. A reflection mirror 69 is provided in the optical system box 71.
A transparent light transmitting plate 72 made of glass or the like is attached so as to close the opening, and the second sheet of printed material 153 is passed through the light transmitting plate 72.
Is incident on the imaging camera 67 by the reflection mirror 69. The light transmitting plate 72 is set so as to have an angle in an overhang shape with respect to the horizontal plane, so that dust and the like do not accumulate. The optical system boxes 70 and 71 are attached to the machine frame so that the position can be adjusted. Each imaging camera 59, 6
The image data obtained in step 7 is sent to the judgment means (not shown).

The operation of the above configuration will be described below. A plurality of packaging components 152 as described above
Is printed on the front and back sides and dried, and the printed sheet 153 is conveyed onto the inspection cylinder 41. Then, the sheet printed matter 153 is moved along the inspection cylinder 41 by the pressing member 42, and in this state, the first printed surface of the sheet printed matter 153 extends from the leading end to the trailing end, and is sequentially turned on by the illumination light sources 56 and 57. The reflected light is illuminated, and the reflected illuminated portion is
9 (the pressing member 42 is connected to the illumination light source 5
It is also possible to prevent the printed sheet 153 from jumping up to the fourth side. ). Subsequently, the sheet printed matter 153 is discharged from the inspection cylinder 41, and is gripped on the sprocket 45 by the gripping means 49 attached to the chain 44 on which the leading end of the sheet printed matter 153 is running. Guide member 5
It is conveyed along the 0 guide surface. During this conveyance, the second print surface of the sheet-fed printed material 153 extends from the leading end to the trailing end, and is sequentially reflected and illuminated by the illumination light sources 61 and 62, and the reflected illuminated portion passes through the light transmitting plate 72. Through the reflection mirror 69, the image is taken by the imaging camera 67.

In the meantime, the judgment means based on the image pickup data by the image pickup cameras 59 and 67, as in the above embodiment,
It is determined whether or not there is a defect on each printing surface of the sheet-fed print 153. Then, as a result of the determination by the determining means, if the sheet printed matter 153 is non-defective, the gripping means 49 holding the printed matter 153 is released at the position of the non-defective receiving box 53, and the non-defective sheet printed matter being gripped is discharged. 153 is good product receiving box 5
Drop to 3. On the other hand, if the sheet printed matter 153 is defective, the holding means 4 holding the sheet printed matter 153
9 is released at the position of the defective product receiving box 52, and the gripped defective sheet printed material 153 is dropped into the defective product receiving box 52.

As still another embodiment of the present invention, although not shown, for example, when a second inspection surface is directly imaged from below by an imaging camera, a light transmitting plate as a cover is provided. The imaging camera may be housed in the optical system box. Alternatively, the optical system box may be unnecessary by using only the light transmitting plate and expanding it to extend to the side and using it as a cover. In short, the imaging unit can be covered only with the light transmitting cover so as not to be affected by dust or the like.

In the second embodiment, when the sheet printed matter 153 is inspected at the inclined linear portion, the illuminating means 6 is used.
1, 62 may be taken out to the side of the sheet-fed print 153 and replaced. Further, in each embodiment, the light sources 14, 15, 5, which illuminate the first printing surface of the sheet-fed print 153.
If it is not possible to take an exchange space between the impression cylinder 3 and the inspection cylinder 41, the ejection cylinders 4 and 55 may be taken out to the side and exchanged. In each embodiment,
Various inspection positions of the first and second printing surfaces can be selected. For example, in the second embodiment, the sheet-fed printed matter 15
An inspection unit using the same imaging means as that of the first embodiment can be used by providing three horizontal guide units. In each embodiment, the first and second inspection surfaces can be inspected at the same position. Further, the judgment means can be used individually for the first and second inspection surfaces. Also, the guide means for the sheet-fed printed matter 153 is not limited to the above embodiments. For example, the sheet-fed printed matter 153 may be straddled between a pair of cylinders having a suction hole and fluttered. It can also be transported so that it does not. Further, the illumination light source may not be used in combination for the bright field and the dark field for some inspection objects. Further, depending on the material of the inspection object, etc., a combination of a reflection illumination light source and a transmission illumination light source may be used, or only a transmission illumination light source may be used. In addition, various lamps such as a halogen lamp can be used as each illumination light source in addition to the fluorescent lamp. If necessary, a light diffusing member is provided in front of the illumination light source so that light from the illumination light source is printed on a sheet-fed print 153. Can be almost uniformly scattered over the entire imaging region. Further, the light transmitting plate and the light transmitting cover in front of the imaging unit are not limited to a transparent material, and may be a transparent material provided with a filter. In addition, the present invention can be variously changed in design without departing from the basic technical idea.

[0036]

As described above, according to the quality inspection apparatus of the present invention, the first inspected surface and the second inspected surface of the inspected object are respectively conveyed during the transport of the inspected object once. An image is taken by the imaging means, and the presence / absence of a defect on the first inspection surface and the second inspection surface is determined by the determination means based on the imaging result. Even if the inspection object is transported once, both the front and back sides can be inspected while the object is transported once. Therefore, the work efficiency of quality inspection can be improved.

Further, an image pickup means for picking up an image of a second inspected surface of the inspected object is arranged below the conveyed inspected object, so that an image pickup section can image the second inspected surface. By providing the covering body to cover, the second inspection surface is imaged so as not to be affected by falling dust and the like, and erroneous determination can be prevented, and the detection accuracy can be further improved.

Further, the imaging means is arranged below the object to be inspected, and the imaging means is configured to be able to image the second surface to be inspected via the reflection mirror. The second inspection surface of the object can be imaged.

Further, a light transmitting cover is used as a coating,
By making the light transmitting cover have an angle with respect to the horizontal plane, it is possible to make it difficult for dust or the like to adhere. Even if dust or the like adheres, it is easily and reliably removed by blowing air or the like. And the detection accuracy can be further improved.

Further, by storing the image pickup unit in the optical system box, the influence of dust and the like can be more effectively suppressed. By setting the light transmitting plate of the optical system box at an angle with respect to the horizontal plane, As described above, the adhesion of dust and the like can be effectively prevented.

Further, by circulating a cooling medium through the optical system box, even if the cooling medium is installed near the heating source, the imaging unit,
The illumination light source etc. can function reliably,
The service life can be extended.

Further, by supporting the illuminating means or the illuminating means and the imaging means so as to be able to be taken out to the side, it is possible to easily and quickly replace them, and to continue the automatic inspection work at an early stage. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a part of a quality inspection apparatus according to a first embodiment of the present invention applied to a sheet-fed print apparatus (in-line).

FIG. 2 is an enlarged view showing an inspection unit on a second inspection surface (back surface) side in the quality inspection apparatus.

FIG. 3 is a partially broken plan view of the inspection unit.

FIG. 4 is a partially broken plan view for explaining a state in which an illumination light source and the like are taken out to the side in the inspection unit.

FIG. 5 is a schematic side view in which a quality inspection device according to a second embodiment of the present invention is applied to a transport device (offline) dedicated to inspection of sheet-fed prints.

FIG. 6 is an enlarged view showing an inspection unit on a second inspection surface (back surface) side in the quality inspection apparatus.

FIG. 7 is a front view showing an example of a sheet-fed printed material in which a packaging box structure is printed on the surface of a sheet.

FIG. 8 is a rear view illustrating an example of a sheet-fed printed material in which a packaging box structure is printed on the back surface of a sheet.

[Explanation of symbols]

 Reference Signs List 4 transport means 8 gripping means 9 guide member 14 illumination light source 15 illumination light source 16 imaging camera 20 imaging means 21 imaging camera 22 reflection mirror 23 optical system box 24 illumination light source 25 illumination light source 30 light transmitting plate 31 supply port 32 discharge port 36 determination means Reference Signs List 41 inspection cylinder 43 transport means 49 gripping means 50 guide member 54 illumination light source 55 illumination light source 58 imaging means 59 imaging camera 61 illumination light source 62 illumination light source 66 imaging means 67 imaging camera 69 reflection mirror 70 optical system box 71 optical system box 72 light transmission Board 153 sheet print

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshitaka Hikami 1-5 Kagamiba Oyanagicho, Minami-ku, Kyoto F-term (reference) in Duck Engineering Co., Ltd. 2G051 AA34 AA90 AB11 BA01 BB20 CA03 CA04 CA07 CC20 DA01 DA06 DA13 EA11 EB01

Claims (13)

[Claims] An illumination unit for illuminating first and second inspection surfaces of the inspection object while the inspection object is being transported, and an image of each inspection surface illuminated by the illumination unit. A quality inspection apparatus, comprising: an imaging unit; and a determination unit that determines presence or absence of a defect on the inspection surface based on an output from each of the imaging units. 2. The quality inspection apparatus according to claim 1, wherein imaging means for imaging a second inspection surface of the inspection object is arranged below the transported inspection object. 3. An image pickup unit for picking up an image of a second surface to be inspected of the object to be inspected, comprising: an image pickup unit; and a covering body that covers the image pickup unit so as to image the second surface to be inspected. The quality inspection device according to claim 2, comprising: 4. The quality inspection apparatus according to claim 3, wherein the imaging section for imaging the second inspection surface comprises an imaging camera. 5. The quality inspection apparatus according to claim 3, wherein the imaging unit for imaging the second inspection surface includes an imaging camera, and a mirror for reflecting the second inspection surface on the imaging camera. 6. The quality inspection apparatus according to claim 3, wherein the covering is a light transmitting cover. 7. The quality inspection apparatus according to claim 6, wherein the light transmitting cover is set to have an angle with respect to a horizontal plane. 8. The optical system box for accommodating an imaging unit, wherein the cover is configured to be able to image the second surface to be inspected by the imaging unit through a light transmitting plate of the optical system box. 5. The quality inspection device according to any one of 5. 9. The quality inspection apparatus according to claim 8, wherein the light transmitting plate is set to have an angle with respect to a horizontal plane. 10. The quality inspection apparatus according to claim 8, wherein the illumination means is housed in an optical system box. 11. The quality inspection apparatus according to claim 8, wherein the optical system box is configured to circulate a cooling medium. 12. The quality inspection apparatus according to claim 2, wherein the illumination means for the second inspection surface is supported so as to be able to be taken out to the side. 13. An illumination unit and an imaging unit on the second surface to be inspected are supported so as to be able to be taken out sideways.
The quality inspection device according to any one of the above.