JP3377628B2 - Lighting equipment for print quality inspection equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an illuminating device of a print quality inspection device for automatically inspecting the quality of printed matter continuously printed or conveyed.

[0002]

2. Description of the Related Art An example of a print quality inspection apparatus as described above is shown in FIG. This consists of an inspection device, a plate cylinder 1 for winding a plate and a blanket cylinder 2 for winding a blanket.
This is an example of application to a sheet-fed offset printing machine in which a transfer from a plate to a rubber blanket is transferred to a printing paper or a metal sheet, which has a pressure cylinder 3 for applying pressure.

This inspection apparatus generally includes a camera 4 as a detector for taking in as image data the printing state of the printing paper or the metal sheet supplied to the impression cylinder 3 after printing on the sheet surface, and the above-mentioned sheet surface. An illumination unit 55 for irradiating a printing state with light of high illuminance and a rotary encoder provided at the shaft end of the impression cylinder 3 to obtain a vertical synchronization (positioning) signal of the printing sheet sent out as the printing machine rotates. Synchronization device 6 such as the above, the camera 4 and the synchronization device 6
And a control unit 7 to which signals from and are input. Then, in the control unit 7, the reference image data of the print sheet surface captured by the camera 4 at the start of printing and the determination image data of the print sheet surface captured by the camera 4 at the time of printing are corresponded based on the signal from the synchronization signal 6. The quality of printing is determined by comparing the two levels and determining whether the level difference between the two is within a predetermined allowable range. Further, when the control unit 7 determines that there is a printing defect such as oil stain, the position is displayed on the CRT display, an alarm is sounded, and at the same time, the tape inserter 8 or the like is operated as a mark for selecting a defective sheet in a subsequent process. It is designed to let you.

In the figure, 9 is an air blower type paper pressing device and 10 is a paper ejection cylinder. By the way, as the illumination unit 55 of the conventional print quality inspection apparatus, there are well known ones using a halogen lamp or the like, and one that makes light collected on a condenser reflecting mirror through a large number of optical fibers to form a light source on a line. ing. However, in the former lighting unit,
When the size of the printed matter becomes large, a large number of lamps are required, which causes an increase in cost and complicates the device. In the latter lighting unit, the device becomes large in size and costly, and the fiber breaks and There was a problem that a uniform light amount could not be obtained in a line due to variations in the transmittance of the fiber itself.

As a countermeasure against this, use of a fluorescent lamp used in a facsimile or the like is considered. However, when the fluorescent lamp is used as it is, the cost is low and the maintainability is good, but it is weak against physical impact, and it is not possible to obtain a sufficient amount of light, and the color rendering does not have an appropriate spread in the entire visible region. Since it is a discharge type, there is a drawback that a shading phenomenon in which the amount of light at both ends is smaller than that in the central part and flicker are likely to occur.

Therefore, in order to eliminate the above-mentioned drawbacks
No. 80446 gazette is disclosed, but in order to suppress the shading phenomenon, using a fluorescent lamp in which a connecting pipe part is bent from both ends of a straight tubular main body pipe part makes it a special order for the fluorescent lamp and the cost UP is increased. Inevitable. Also,
The use of high frequency power supplies to prevent flicker is a known technique.

[0007]

In order to use a fluorescent lamp, it is necessary to improve it by using a known conventional technique, but it will not be put to practical use unless the problems described below are solved. (1) In order to obtain a sufficient amount of light from the fluorescent lamp, it is necessary to bring the fluorescent lamp as close as possible to the focus of the camera.
However, some measures are required to prevent the impact of a relatively hard sheet such as a metal sheet or to prevent the printed surface from becoming dirty. (2) In order to obtain a sufficient amount of light from the fluorescent lamp, it is necessary to enclose the fluorescent lamp with a reflector to form a lamp house-like structure. However, with the above structure, the temperature inside the lamp house becomes abnormal. Rise and shorten the life of the fluorescent lamp,
Fluctuations in the amount of light pose a problem. Therefore, it is necessary to take measures to prevent the temperature rise in the lamp house.

An object of the present invention is to provide an illuminating device which has been developed in order to deal with such a problem and which can obtain a sufficient amount of light without physical impact.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the structure of the present invention is applied to a lamp house formed longer than the width of the impression cylinder in a direction of 45 degrees from the focus of the camera for inspecting the print quality of the impression cylinder surface. In addition, a pair of fluorescent lamps installed so as to sandwich the focus at a position corresponding to the diameter of the impression cylinder, a lamp protection transparent plate for protecting the fluorescent lamps, and the inside of the lamp house room covered with the lamp protection transparent plate An air suction hole for sucking air, a jet air nozzle for injecting air to the impression cylinder,
An air chamber connected to the jet air nozzle is provided.

Further, the jet air nozzles are inclined to the opposite side of the direction of rotation of the impression cylinder at an injection angle of 4 to 8 degrees, and the first to third angles are set.
The injection angle is 30 to 6 on the opposite side of the rotation direction of the nozzle and the impression cylinder.
It is characterized in that it is formed on a fourth nozzle inclined at 0 degree. Furthermore, the nozzle diameter of the jet air nozzle should be 2 to 3
mm and the nozzle pressure is 0.4 to 1.8 kg / cm ² .

Further, a variable capacity jet air device for varying the output of a sheet on the surface of the impression cylinder is connected to the air chamber.

[0012]

According to the present invention, the above-mentioned means allows the pair of fluorescent lamps to illuminate the focus of the camera for detecting print quality to obtain a sufficient amount of light, and the transparent plate for protecting the lamp allows the fluorescent lamps to contact the printing surface. The air from the jet air nozzle prevents the impact on the fluorescent lamp of a relatively hard sheet such as a metal sheet, and the air suction hole prevents the abnormal temperature rise in the lamp housing, thereby preventing the fluorescent lamp. Prolong the life of.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a device layout diagram embodying an embodiment of the present invention. In this embodiment, the printing quality inspection apparatus has a plate cylinder 1 that winds a plate, a blanket cylinder 2 that winds a rubber blanket, and an impression cylinder 3 that applies pressure. This is an example applied to a sheet-fed offset printing machine that transfers to a metal sheet.

The present apparatus generally includes a camera 4 as a detector that captures the printing state of the printing paper or the metal sheet, which is supplied to the impression cylinder 3, on the surface of the sheet after printing, as a detector.
A lamp house 5 that illuminates the printing state on the surface of the sheet with high-intensity light, and a shaft end of the impression cylinder 3 to obtain a synchronization (alignment) signal in the vertical direction of the printing sheet that is sent out as the printing machine rotates. And a control unit 7 to which signals from the camera 4 and the synchronization device 6 are input. Then, in the control unit 7, the reference image data of the print sheet surface captured by the camera 4 at the start of printing and the determination image data of the print sheet surface captured by the camera 4 at the time of printing are corresponded based on the signal from the synchronization signal 6. The quality of printing is determined by comparing the two levels and determining whether the level difference between the two is within a predetermined allowable range. Further, when the control unit 7 determines that there is a printing defect such as oil stain, the position is displayed on the CRT display, an alarm is sounded, and at the same time, the tape insert 8 or the like is operated as a mark for selecting a defective sheet in a subsequent process. It is designed to let you. As described above, the process of print quality inspection is the same as in the prior art.

Next, the lamp house 5 according to the present invention shown in FIG. 1 will be described in detail. As shown in FIG. 2, the lamp house 5 is installed on the impression cylinder by cutting out the machine frame 21. This is because when the fluorescent lamp 31 is used, the tube end becomes dark due to the shading phenomenon. Therefore, in order to inspect the print quality of the maximum sheet without fluctuation of the illuminance in the width direction, the fluorescent lamp 31 is used so as not to have the above influence. This is because the lamp house 5 needs to be longer than the impression cylinder surface length, which facilitates the positioning of the lamp house 5. However, when detached, the lamp house 5 comes into contact with the machine frame 21, which makes it difficult to remove, so a bearing is provided on the contact surface.

As shown in FIG. 3, the lamp house 5 further includes a fluorescent lamp 31, an air chamber 32, a fluorescent lamp protection transparent plate 33, a jet air nozzle 34, and an air suction hole 35.
The camera has a camera viewing hole 36, an air suction tube 37, an air suction filter 38 for preventing air, floating dust, and ink mist from entering through the air suction hole 35, and the fluorescent lamp 31.
In order to increase the illuminance efficiency with respect to the camera focus, the camera focus should be sandwiched at a position L mm away from the camera focus.
Two are installed at the 5 degree position, and the jet air nozzle 3 is also installed.
No. 4 is the first to third nozzles 34a inclined to the opposite side of the direction of rotation of the impression cylinder 3 at an injection angle of 4 to 8 degrees, and the fourth inclined to the opposite side of the direction of rotation of the impression cylinder at an angle of injection of 30 to 60 degrees. 4 nozzles 34
b, the first to third nozzles 34a suppress the lifting of the sheet at the camera focus, and the fourth nozzle 34b forms a large angle to suppress the sheet flutter link near the camera focus as much as possible.

Further, the air chamber 32 and the air suction hole 3
5 shows the lamp house 5 as seen from the left side and FIG. 4b as the lamp house 5 seen from the right side, the air chamber 32 is long along the width direction of the impression cylinder, and the air suction hole 3 is provided.
5 is provided in a dot shape, and the jet air nozzle 34 and the fluorescent lamp protection transparent plate 33 are provided along the width direction of the impression cylinder as shown in FIG.

Thus, the protective transparent plate 33 prevents the fluorescent lamp 31 from being broken due to the flapping of the sheet and also prevents floating dust and ink mist from adhering to the fluorescent lamp 31, and the air suction hole 35 causes the abnormal temperature in the lamp house. Prolonging the life of the fluorescent lamp by preventing the rise. 41 in FIG.
Is a jet air discharge port to the air chamber 32, 42 is a cable terminal hole for supplying power to the fluorescent lamp 31, and 43
Indicates an air suction port.

The lamp house 5 is provided with a jet air device 11 and an air suction device 16 as shown in FIG.
The jet air device 11 is controlled by a controller 18 that issues a command to vary the strength of the jet air according to the output of a displacement gauge 14 that detects the amount of lifting of the sheet, and thus the strength of the jet air is independent of the thickness and material of the sheet. Optimally, and the air suction device 16 is
The air sucked from the air suction hole 35 and collected in the air suction pipe 37 is sucked from the air suction port 43 to prevent the temperature rise of the fluorescent lamp 31.

The movement of the sheet 12 according to the above-described embodiment will be described in detail. As a result of the example, the sheet 12 conveyed from the intermediate member 17 is passed to the claw 13 of the impression cylinder 3 as shown in FIG. The impression cylinder 3 rotates in the direction of the arrow in the figure, and the sheet 12 is printed while being pressed against the blanket cylinder 2 and is guided to the detection point of the camera 4 of the print quality inspection device, and the print quality inspection device and the sheet 12 are connected. The focus is on the blanket cylinder 2 and the impression cylinder 3 and the sheet 1
The sheet 12 is sandwiched and the sheet 12 is in close contact with the impression cylinder, so that it does not get out of order.

As shown in FIG. 1, while the bottom of the seat 12 is separated from the blanket cylinder 2 and the impression cylinder 3 and the seat bottom of the seat 12 contacts the seat guide 15, for example, under the following conditions, At a point of 200 mm or more, the sheet 12 is in close contact with the impression cylinder 3, and the camera 4 and the sheet 1
The focus with 2 does not get out of order. For example, the diameter of the impression cylinder 3 is 760m.
m, the distance from the surface of the impression cylinder 3 of the sheet guide 17 mm,
Sheet material is iron plate, sheet size is 0.28t × 622
In the case of L × 1066 W (mm), the sheet guide 15 is installed in a vertical line shape as shown in FIG.
The seat guides 15 are provided in the lower part so that the seats 12 are not affected by the seat guides 15. Therefore, the upper part of the lamp house 5 whose quality has been inspected does not overload the claws 13 of the chain gripper. The sheet guide 15 is arranged. In this case, the original pressure of the nozzle is 1.0 kg
/ Cm ² , the nozzle outlet diameter is 2.4 mm, the nozzle interval is 50 mm, and the pump flow rate is 135 m ³ / h, so that the sheet 12 is completely pressed by the jet air.

When the sheet is a paper of 0.2 mm or less, the second nozzle and the third nozzle are sufficient jet air nozzles.

[0023]

As described above, according to the present invention, a lamp house formed longer than the width of the impression cylinder is positioned at 45 degrees from the focus of the camera for inspecting the print quality of the impression cylinder surface and at a position corresponding to the diameter of the impression cylinder. A pair of fluorescent lamps that are installed so as to sandwich the focus, a lamp protection transparent plate that protects the fluorescent lamps, and an air suction hole that sucks air in the lamp house chamber that is covered with the lamp protection transparent plate. Since the jet air nozzle for injecting air to the impression cylinder and the air chamber connected to the jet air nozzle are provided, the sheet on the impression cylinder can be effectively illuminated for a long time even by a general-purpose fluorescent lamp. The air prevents the print surface from being scratched due to the flapping of the sheet and the fluorescent lamp from being impacted, and the print surface is not damaged. Kept by an effect such as never cause a decrease in luminosity.

[Brief description of drawings]

FIG. 1 is a schematic layout diagram of a print quality inspection apparatus according to an embodiment of the present invention.

FIG. 2 is a layout view of a lamp house in FIG.

FIG. 3 is a detailed view of the lamp house in FIG.

4A and 4B are perspective views of the lamp house in FIG. 1, where FIG. 4A is a left side perspective view, FIG. 4B is a right side perspective view, and FIG. 4C is a lower perspective view.

FIG. 5 is a schematic layout diagram of a print quality inspection apparatus according to a conventional example.

[Explanation of symbols]

3 impression cylinder 4 cameras 5 lamp house 31 fluorescent lamp 32 air chambers 33 Lamp protection transparent plate 34 Jet Air Nozzle 35 Air suction hole 37 Air suction tube

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41F 33/14 B41F 21/00 H01J 61/32

Claims (4)

(57) [Claims] 1. A lamp house which is formed longer than the width of the impression cylinder, and a lamp house which is 4 times from the focus of a camera for inspecting the print quality of the impression cylinder surface.
A pair of fluorescent lamps installed so as to sandwich a focus at a position corresponding to the diameter of the impression cylinder in the direction of 5 degrees, a lamp protection transparent plate for protecting the fluorescent lamp, and the lamp protection transparent plate covered with the above. An air suction hole for sucking air in the lamp house chamber, a jet air nozzle for injecting air to the impression cylinder,
An illuminating device for a print quality inspection device, comprising an air chamber connected to the jet air nozzle. 2. The first to third nozzles in which the jet air nozzles are inclined at an injection angle of 4 to 8 degrees on the opposite side of the direction of rotation of the impression cylinder, and the injection angles 30 to 6 on the opposite side of the direction of rotation of the impression cylinder.
The illumination device of the print quality inspection apparatus according to claim 1, wherein the illumination device is formed on the fourth nozzle inclined at 0 degree. 3. The jet air nozzle has a nozzle diameter of 2 to 3 mm and a nozzle pressure of 0.4 to 1.8 kg / c.
The lighting device of the print quality inspection device according to claim 1, wherein the lighting device is m ² . 4. The print quality inspection apparatus according to claim 1, wherein a variable capacity jet air device that is variable according to the output of a displacement meter that detects the amount of sheet lifting on the surface of the impression cylinder is connected to the air chamber. Lighting equipment.