CN115972763A - Printing system of offset rotary press and offset rotary press - Google Patents

Abstract

A printing system of an offset rotary press and an offset rotary press, which can grasp the emulsification state of ink in a plate cylinder in real time, quickly set the emulsification state of the ink to an appropriate emulsification state, maintain good printing quality from the start to the end of printing, and reduce waste paper. A printing system of an offset rotary press (1) is provided with a light source (32) for irradiating irradiation light (71) to the surface of a plate cylinder (6) of a printing unit (5); a camera (33) for capturing reflected light (72) from the irradiated irradiation light (71); and a control device (56) which binarizes the image captured by the camera (33) into a range in which the luminance of the reflected light (72) is high and a range in which the luminance of the reflected light (72) is low, and calculates the area ratio of the range in which the luminance of the reflected light (72) is high with respect to the entire area of the image captured by the camera (33), wherein when the area ratio of the range in which the luminance of the reflected light (72) is high calculated by the control device (56), the supply of dampening water by the dampening water device (11) is controlled, and the appropriate emulsified state of the ink is obtained.

Description

Printing system of offset rotary press and offset rotary press

Technical Field

The present invention relates to a printing system of an offset rotary press and an offset rotary press provided with the printing system.

Background

In printing by an offset rotary press, dampening water and ink are supplied to a plate cylinder. If the supply amount of dampening water is large, excessive emulsification of ink occurs. If excessive emulsification of ink occurs, printing contamination or the like occurs, and waste paper is produced.

Since the emulsified state of ink varies depending on various factors such as the pattern to be printed and the temperature, the emulsified state of ink has conventionally been judged by the expertise and experience of an operator to adjust the supply of dampening water. Therefore, depending on the operator, a problem occurs in that the print quality varies.

On the other hand, conventionally, as disclosed in japanese patent application laid-open No. 2005-007769 (patent document 1), a printing system is known which performs control of printing by performing machine learning based on measurement of a color tone of a printing result and an operating state of a printing press.

However, the printing system disclosed in patent document 1 does not detect the emulsified state of the ink during printing, and therefore has the following problems: a time lag occurs between the ink change to the excessively emulsified state and the execution of the control, and it takes time until the ink becomes an appropriate emulsified state of the ink, and a large amount of waste paper and the like are generated.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a printing system of an offset rotary press and an offset rotary press, each of which includes: the emulsion state of ink is grasped in real time, the sign of the over-emulsion state of ink is rapidly known, dampening water is controlled to make the emulsion state of ink appropriate, good state of printing quality can be maintained from the beginning to the end of printing, waste paper can be greatly reduced, and the ink can be easily introduced into the existing offset rotary press at low cost.

Disclosure of Invention

The printing system of the offset rotary press of the present invention is characterized in that the offset rotary press includes at least one printing unit including a plate cylinder, a dampening water device for supplying dampening water to the plate cylinder, and an ink device for supplying ink to the plate cylinder, and includes an ink emulsified state detecting means including a light source for irradiating light onto a surface of the plate cylinder and/or a surface of a roller of any one of the ink devices; a camera for shooting the reflected light reflected from the surface of the roller; and a control unit configured to binarize the image captured by the camera into a high-luminance range and a low-luminance range of the reflected light, and to calculate an area ratio of the high-luminance range of the reflected light with respect to an entire area of the image captured by the camera, wherein the control unit controls supply of the dampening water device to achieve an appropriate emulsified state of the ink when the area ratio of the high-luminance range of the reflected light calculated by the control unit is high.

In the printing system of the offset rotary press according to the present invention, the following structure is made: the light source irradiates irradiation light of a specific wavelength, and the camera captures only reflected light of the specific wavelength.

In the printing system of an offset rotary press according to the present invention, the temperature of the dampening water supplied from the dampening water device and the temperature of the ink supplied from the ink device are kept constant.

With this configuration, the emulsified state of the ink can be accurately determined from the area ratio in the range where the luminance of the reflected light is high.

In the printing system of the offset rotary press of the present invention, the light source is a high-color-rendering LED.

With this configuration, since the change in the luminance of the reflected light can be detected more clearly, the control based on the detection result can be performed more accurately.

In the printing system of an offset rotary press according to the present invention, the control module repeatedly calculates an area ratio in a range where the luminance of reflected light is high during printing, stores the area ratio, mechanically learns a control model of dampening water in an appropriate emulsified state of ink in accordance with the stored area ratio, and updates the control model to the control model in the appropriate emulsified state of ink in accordance with the calculated area ratio.

With this configuration, the stable emulsified state of the ink can be always grasped regardless of the experience and skill of the operator, and the dampening water can be reliably controlled.

In the printing system of an offset rotary press according to the present invention, the control unit stores at least one of information of an operating state of the offset rotary press, detection information of a printing result, and temperature and humidity in addition to the area ratio, performs machine learning of the control model based on the stored area ratio and information of a storage other than the area ratio, and updates the control model to the control model corresponding to the information.

With this configuration, even if at least one of the operating state of the offset rotary press, the detection information of the printing result, the temperature and the humidity changes, the stable emulsified state of the ink can be grasped, and the dampening water can be reliably controlled.

In the printing system of an offset rotary press according to the present invention, the operating condition of the offset rotary press includes at least one of a supply amount of dampening water at the start of printing, a supply amount of ink at the start of printing, information on a printed pattern, a printing speed during printing, a supply amount of dampening water during printing, and a supply amount of ink during printing.

In the printing system of an offset rotary press according to the present invention, the detection information of the printing result includes at least one of a dot shape, a dot area ratio, and an ink density detected from the printing result.

In the printing system of an offset rotary press according to the present invention, the information on the temperature and humidity includes at least one of a dampening water temperature at the start of printing, an ink temperature at the start of printing, a water passing temperature of a swing roller at the start of printing, a water passing temperature of a plate cylinder at the start of printing, a temperature in a factory at the start of printing, a humidity in a factory at the start of printing, a dampening water temperature in printing, an ink temperature in printing, a water passing temperature of a swing roller at the printing, a water passing temperature of a plate cylinder at the printing, a temperature in a factory at the printing, and a humidity in a factory at the printing.

In the printing system of an offset rotary press according to the present invention, the update of the control model is performed on a cloud server independent from the offset rotary press.

In the printing system of an offset rotary press according to the present invention, the update of the control model is performed by a control device in the offset rotary press.

In the printing system of an offset rotary press according to the present invention, dampening water of the dampening water device is controlled using the updated control model.

The offset rotary press of the present invention includes the printing system.

According to the printing system of the offset rotary press of the present invention, the emulsified state of the ink is grasped in real time, the sign of the over-emulsified state of the ink is rapidly known, the dampening water is controlled, the emulsified state of the ink can be made appropriate, the good state of the printing quality can be maintained from the start to the end of the printing, and the waste paper can be greatly reduced.

Moreover, the present invention can be easily introduced into an existing offset rotary press at low cost.

Further, since the emulsified state of the ink is determined according to the area ratio in the range where the luminance of the reflected light is high, the emulsified state of the ink can be appropriately set even if the emulsified state of the ink is not uniform.

Drawings

Fig. 1 is a front view of an entire offset rotary press to which the printing system of the present invention is applicable.

Fig. 2 is a structural view of the printing unit.

Fig. 3 is a schematic diagram of a control system related to machine learning.

Fig. 4 is a configuration diagram showing a second embodiment of the reflected light detection device.

Fig. 5 is a configuration diagram showing a third embodiment of the reflected light detection device.

Detailed Description

An offset rotary press according to an embodiment of the present invention will be described with reference to fig. 1. Fig. 1 is a front view of an entire offset rotary press to which the printing system of the present invention is applicable.

An offset rotary press 1 according to an embodiment of the present invention includes a paper feed unit 2 for feeding a substrate W to be printed; a printing unit 3 for printing on the printing substrate W conveyed from the paper feed unit 2; and a paper discharge unit 4 for discharging the printing substrate W printed by the printing unit 3.

The paper feeding unit 2 includes a paper feeding shaft 91 on which a printing substrate W wound in a roll shape is mounted; and a paper feed roller 92 on the paper feed side for feeding the printing substrate W mounted on the paper feed shaft 91 to the printing unit 3. The feed roller 92 on the paper feed side is rotationally driven by a drive motor, not shown, to pull the printing substrate W, rotate the paper feed shaft 91, and feed the printing substrate W in a roll shape toward the printing unit 3.

The paper feed section 2 is not limited to this configuration, and may be a configuration of a paper feed section of a known rotary machine such as a configuration for feeding out a sheet of paper.

The printing unit 3 includes a plurality of printing units 5 described later, and each printing unit 5 performs monochrome printing. The drying device 95 is provided on the sheet discharge side of each printing unit 5, but may not be provided.

The paper discharge unit 4 includes a paper discharge-side feed roller 93 that feeds the printed substrate W printed by the printing unit 3 to the paper discharge unit 4; and a take-up reel 94 for taking up the printing substrate W.

The paper discharge unit 4 is not limited to this configuration, and may be a configuration of a paper discharge unit of a known rotary press, such as a feeder device for discharging the printing substrate W to another processing device, a stacking device for stacking sheet papers, or the like.

A dot detection device 41 and a pattern inspection device 42 for inspecting the result of printing are provided between the printing unit 3 and the sheet discharge unit 4. The dot detection device 41 and the pattern inspection device 42 are not limited to this configuration, and may be provided at any position on the downstream side of the printing unit 3, such as between the feed roller 93 on the paper discharge side and the winding shaft 94 that winds the printing target substrate W.

The configuration of the offset rotary press 1 to which the printing system of the present invention can be applied is not limited to this configuration, and any configuration may be adopted such as a processing section for performing cutting processing and bending processing of the printing target substrate W may be provided between the printing section 3 and the paper discharge section 4.

The printing system of the present invention is applicable regardless of the type of the substrate W to be printed. Therefore, as the substrate W to be printed, a material used in a known offset rotary press, such as paper or film, can be used. In addition, the paper can be used regardless of the form of the continuous paper, the flat paper, or the like.

The structure of the printing unit 5 will be described with reference to fig. 2. Fig. 2 is a structural view of the printing unit.

The printing section 3 is constituted by at least one printing unit 5. In the printing unit 5, the printing target substrate W is printed with an arbitrary ink. In the embodiment of fig. 1, four printing units 5 are provided, and printing is performed with yellow (Y), cyan (C), magenta (M), and black (K) inks. The printing units 5 are all of the same construction.

The number of printing units 5 used in the printing system of the present invention is not limited to the embodiment of fig. 1, and the printing portion 3 may be configured by an arbitrary number of printing units 5 such as only one printing unit that performs printing with black (K) ink. The ink that can be used is not limited to the yellow (Y), cyan (C), magenta (M), and black (K) described above, and any color ink such as a specific color can be used.

As shown in fig. 2, the printing unit 5 has a plate cylinder 6, a blanket cylinder 7, and an impression cylinder 8. The plate cylinder 6, the blanket cylinder 7, and the impression cylinder 8 are each rotated by a drive motor not shown. The printing substrate W is conveyed between the blanket cylinder 7 and the impression cylinder 8.

Printing was performed as follows. Printing is performed by supplying ink and dampening water to the plate cylinder 6, transferring the ink from the plate cylinder 6 to the blanket cylinder 7, and transferring the ink from the blanket cylinder 7 to the printing substrate W.

To adjust the surface temperature of the plate cylinder 6, cooling water is introduced into the interior of the plate cylinder 6. The details of the introduction of the cooling water will be described later.

A dampening water device 11 that supplies dampening water to the plate cylinder 6 and an ink device 21 that supplies ink to the plate cylinder 6 are provided adjacent to the plate cylinder 6.

The dampening water device 11 includes a dampening water temperature detection device 12, a water pan 13, a water source roller 14, a metering roller 15, and a dampening roller 16.

Dampening water in the water pan 13 is supplied to the plate cylinder 6 through the water supply roller 14, the metering roller 15, and the dampening roller 16. The supply of dampening water into the water tray 13 will be described later.

The dampening water temperature detection device 12 detects the temperature of dampening water in the water pan 13. The temperature of the dampening water measured by the dampening water temperature detection device 12 is used as the dampening water temperature for machine learning described later.

The ink device 21 includes an ink temperature detecting device 22, an ink tank 23, an ink supply roller 24, an ink supply uniform roller group 25, an ink swing roller 26, and an ink roller 27.

The ink in the ink tank 23 is supplied to the plate cylinder 6 through an ink supply roller 24, an ink supply uniform roller group 25, an ink swing roller 26, and an ink roller 27. The ink temperature detection device 22 is provided to face any roller in the ink device 21, and measures the temperature of the ink on the roller surface in a non-contact manner. The temperature of the ink detected by the ink temperature detecting device 22 is used as an ink temperature for machine learning described later.

In order to control the temperature of the ink, cooling water is introduced into the ink oscillating roller 26 to control the surface temperature of the ink oscillating roller 26. The details of the introduction of the cooling water will be described later.

The introduction of cooling water into the plate cylinder 6, the supply of dampening water into the water pan 13, the introduction of cooling water into the ink swing roller 26, and the supply of ink will be described with reference to fig. 3. Fig. 3 is a schematic diagram of a control system related to machine learning.

In order to adjust the surface temperature of the plate cylinder 6, the cooling water introduced into the plate cylinder 6 is supplied from a plate cylinder cooling water circulation device 9 shown in fig. 3 provided in the vicinity of the printing unit 5.

The plate cylinder cooling water circulation device 9 includes a flow path for supplying cooling water from the plate cylinder cooling water circulation device 9 to the plate cylinder 6; a flow path for circulating cooling water from the plate cylinder 6 to the plate cylinder cooling water circulating device 9; and a plate cylinder cooling water temperature control device 10 that controls the temperature of the circulating cooling water.

The temperature of the cooling water controlled by the plate cylinder cooling water temperature control device 10 is used for machine learning described later as a plate cylinder water passing temperature.

The supply of dampening water into the water pan 13 of the dampening water device 11 is performed by a dampening water circulation device 17 shown in fig. 3 provided in the vicinity of the printing unit 5. The dampening water circulating device 17 is provided with a flow path for supplying dampening water from the dampening water circulating device 17 to the water pan 13; and a flow path for circulating the dampening water from the water pan 13 to the dampening water circulating device 17.

The dampening water circulation device 17 includes a dampening water cooling device 18 that cools dampening water, and can control the temperature of the circulated dampening water.

The temperature control of the dampening water in the printing system according to the present invention controls the cooling set temperature of the dampening water cooling device 18 in accordance with a command from the control device 56 shown in fig. 3 so that the temperature of the dampening water in the fountain 13 detected by the dampening water temperature detecting device 12 becomes the set temperature.

The cooling water introduced into the ink oscillating roller 26 is supplied from an ink oscillating roller cooling water circulating device 28 shown in fig. 3 provided in the vicinity of the printing unit 5. The ink oscillating roller cooling water circulating device 28 is provided with a flow path for supplying cooling water from the ink oscillating roller cooling water circulating device 28 to the ink oscillating roller 26; a flow path for circulating the cooling water from the ink oscillating roller 26 to the ink oscillating roller cooling water circulating device 28; and an ink oscillating roller cooling water temperature control device 29 that controls the temperature of the circulating cooling water.

The set temperature of the ink rocking roller cooling water temperature control device 29 is used for machine learning described later as a rocking roller water passage temperature.

The temperature of the ink in the printing system of the present invention is controlled by changing the set temperature of the ink oscillating roller cooling water temperature control device 29 in accordance with an instruction from the control device 56.

The supply of dampening water and ink is controlled as described below based on instructions from the control device 56.

The amount of dampening water supplied to the plate cylinder 6 is controlled by controlling the rotation amounts of the fountain roller 14 and the metering roller 15. The water supply roller 14 and the amount adjustment roller 15 are rotationally driven by a drive motor not shown. In the printing system of the present invention, the rotation amounts of the drive motors of the fountain roller 14 and the metering roller 15 output from the control device 56 are used for machine learning described later as the supply amount of dampening water.

The amount of ink supplied to the plate cylinder 6 is controlled by controlling the rotation amount of the ink supply roller 24. The ink supply roller 24 is rotationally driven by a drive motor not shown. In the printing system of the present invention, the rotation amount of the drive motor of the ink supply roller 24 output from the control device 56 is used for machine learning described later as the ink supply amount.

At the start of printing, the amount of ink supply is initially set as described below, based on the pattern area ratio of the printed pattern.

A plurality of ink keys (not shown) are provided in parallel in the width direction of the ink supply roller 24 shown in fig. 2, and the amount of ink discharged (amount of ink supplied) in the width direction of the ink supply roller 24 is determined by the gap between each ink key and the ink supply roller 24, that is, the opening degree of the ink key.

The pattern area ratio is data converted from data of the printing plate set on the plate cylinder 6, and is data indicating how much the area of the pattern is in the area of the width x the up-down length of the printing plate (product up-down length) which is the same as the width of the ink key.

The controller 56 obtains a pattern area ratio of the width of each ink key in the width direction of the printing plate from the input data of the printing plate, adjusts the opening degree of each ink key according to the obtained pattern area ratio, and initially sets the ink supply amount.

The printing system of the present invention includes an ink emulsion state detection unit that detects the emulsion state of ink by measuring the brightness of reflected light from the surface of the plate cylinder 6 and/or the surface of the roller to which the ink is supplied.

The ink emulsified state detection unit includes a reflected light detection device 31 shown in fig. 1 for detecting reflected light from the surface of the plate cylinder 6 of each printing unit 5, and a control device 56 shown in fig. 3.

Next, the configuration of the reflected light detection device 31 that detects the reflected light 72 from the surface of the plate cylinder 6 will be described with reference to fig. 2.

In order to detect the reflected light 72 from the surface of the plate cylinder 6, a reflected light detection device 31 is provided in the vicinity of the plate cylinder 6. The reflected light detection device 31 has a light source 32 and a camera 33.

As the light source 32, a lamp such as an LED can be used. In particular, as a suitable light source, a high color rendering LED can be used. High color rendering LEDs have high color reproducibility and are generally used as light sources for printing devices and the like.

When a high-color-rendering LED is used as the light source 32, the change in the luminance of the reflected light 72 can be detected more clearly, and therefore, the control based on the detection result can be performed more accurately.

The camera 33 is a wide-angle camera that can photograph the entire width direction (direction parallel to the rotation axis) of the plate cylinder 6, or a camera that can photograph any part of the plate cylinder 6. In the case of a camera that cannot image the entire plate cylinder 6 in the width direction, a plurality of cameras may be provided in the width direction of the plate cylinder 6, and the plurality of images may be combined to obtain the same result as that obtained by a wide-angle camera.

The light source 32 and the camera 33 are configured to be adjustable in position and angle, respectively, to a position where the reflected light 72 can be easily detected.

As indicated by the broken-line arrow in fig. 2, the irradiation light 71 is irradiated from the light source 32 toward the plate cylinder 6, and as indicated by the broken-line arrow in fig. 2, the reflected light 72 reflected by the surface of the plate cylinder 6 is photographed by the camera 33. That is, the camera 33 photographs the region irradiated with the irradiation light 71 in the surface of the plate cylinder 6.

The light source 32 and the camera 33 can be configured as described below.

The light source 32 is configured to emit light of a specific wavelength, and the camera 33 is configured to capture only the reflected light of the specific wavelength emitted from the light source 32 among the reflected light reflected from the surface of the plate cylinder 6.

As shown in fig. 3, the detection result of the reflected light detection device 31 of each printing unit 5, that is, the captured image of the camera 33 is output to the control device 56. The controller 56 analyzes the detection result (captured image) and determines the emulsified state of the ink on the surface of the plate cylinder 6. The control of the reflected light detection device 31 is performed by the control device 56.

The control device 56 of the present embodiment is configured to perform control of the existing offset rotary press 1 and control of machine learning described later, but is not limited to this configuration, and may be configured to perform control by any configuration, such as control of the reflected light detection device 31 and analysis of the detection result (captured image) by a separate control device.

The control of the reflected light detection device 31 and the analysis of the detection result (captured image) are performed as described below.

The control of the reflected light detection device 31 is performed as follows in accordance with the execution of printing. The light source 32 is always turned on during printing, and irradiates the plate cylinder 6 with irradiation light 71. The camera 33 photographs the surface of the plate cylinder 6 during printing to detect the brightness of the reflected light 72 with respect to the irradiated light 71, that is, the brightness of the surface of the plate cylinder 6.

The control device 56 receives images captured by the camera 33 at regular intervals, for example, every time the plate cylinder 6 rotates a plurality of times, and analyzes the captured images.

The imaging range of the camera 33 may be an image including the entire width direction of the plate cylinder 6, or an image of an arbitrary part of the plate cylinder 6.

The image pickup by the camera 33 is performed at an arbitrary timing when a portion of the printing plate attached to the plate cylinder 6 can be picked up with respect to the rotation of the plate cylinder 6. The portion other than the plate cylinder 6 in the captured image is excluded by the control device 56. The range of exclusion is arbitrarily set according to the size of the plate cylinder 6 and the mounting position of the camera 33.

The present invention can be implemented even when a printing plate is attached to only a part of the plate cylinder 6, because the present invention is only required to perform imaging at an arbitrary timing when the portion of the printing plate attached to the plate cylinder 6 can be imaged.

Since the emulsified state of the ink on the surface of the plate cylinder 6 is not uniform in the width direction and the circumferential direction, the brightness of the reflected light 72 from the surface of the plate cylinder 6 is not uniform in the width direction and the circumferential direction, and there are high portions and low portions. It is considered that this is one of the reasons why the dampening water is not uniformly supplied to the surface of the plate cylinder 6.

For this reason, the captured image of the camera 33 is not uniform in brightness throughout the entire screen, and there are bright portions where the brightness of the reflected light 72 is high and dark portions where the brightness of the reflected light 72 is low.

Therefore, the control device 56 binarizes the received image captured by the camera 33 according to whether or not the luminance of the reflected light 72 is higher than the reference value. That is, the reflected light 72 is divided into a portion (bright portion) where the luminance is higher than the reference value and a portion (dark portion) where the luminance of the reflected light 72 is lower than the reference value. The criterion for determining whether the luminance of the reflected light 72 is high is a reference value of the luminance set by machine learning described later, and a part determined to be high above the reference value is less than a part determined to be low below the reference value.

Further, the control device 56 calculates the entire area of the captured image of the camera 33, and calculates the area ratio of the area of the region determined to have the high luminance of the reflected light 72 to the entire area of the captured image of the camera 33 by summing the areas of the regions determined to have the high luminance of the reflected light 72 as the area of the region determined to have the high luminance of the reflected light 72.

When the calculated area ratio is higher than the set value, it is determined that the feed amount of dampening water is large, and control is performed to reduce the feed amount in order to prevent excessive emulsification. That is, if the feed amount of dampening water is large, the area of the region where the brightness of the reflected light 72 is determined to be high is large in the bright portion of the surface of the plate cylinder 6. The set area ratio value is set by machine learning based on detection information of a print result, which will be described later. The dampening water is controlled (the amount of feed water is controlled) by controlling the amount of rotation of the fountain roll 14 and the metering roll 15 by the control device 56.

If the amount of dampening water supplied is reduced, the area of the region in which the brightness of the reflected light 72 is determined to be high is reduced because the bright portion on the surface of the plate cylinder 6 is reduced, and the area ratio is equal to or less than the set area ratio, so that excessive emulsification of the ink on the surface of the plate cylinder 6 can be prevented, and an appropriate emulsified state of the ink can be achieved.

Therefore, by measuring the luminance of the reflected light 72 from the surface of the plate cylinder 6, the emulsified state of the ink can be grasped in real time.

Therefore, the sign of the over-emulsified state of the ink can be detected quickly, and the dampening water can be controlled in response to the perception, so that the emulsified state of the ink can be made suitable in an early stage without causing printing contamination or the like due to the over-emulsification of the ink, and a good state of the printing quality can be maintained from the start to the end of printing. Further, a significant reduction in waste paper can be expected.

Further, since the emulsified state of the ink is determined according to the area ratio of the range where the luminance of the reflected light 72 is high, even if the emulsified state of the ink on the surface of the plate cylinder 6 is not uniform, the emulsified state of the ink can be appropriately set.

Further, since the reflected light detection device 31 and the control device 56 are provided, it is possible to introduce the existing offset rotary press at low cost and easily, and thus, it is possible to realize not only the newly developed offset rotary press but also the existing offset rotary press already in operation, grasp of the emulsified state of the ink and reliable control.

As shown in fig. 3, the control device 56 communicates with the cloud server 51. The cloud server 51 is provided independently of the offset rotary press 1, and executes machine learning described later.

That is, the control unit of the present embodiment is configured by the control device 56 and the cloud server 51, and the process of machine learning described later can be arbitrarily shared by the control device 56 and the cloud server 51.

In the printing system of the embodiment, while printing is being executed, the area ratio in the range in which the brightness of the reflected light 72 from the surface of the plate cylinder 6 is determined to be high is repeatedly calculated, the control device 56 or the cloud server 51 stores the data of the calculated area ratio, determines the emulsified state of the ink in accordance with the stored area ratio, and mechanically learns the control model of the dampening water that is in the appropriate emulsified state of the ink.

Then, the control device 56 or the cloud server 51 updates the control model of dampening water to the control model output of the supply of the most appropriate dampening water that is in the appropriate emulsified state of ink, in accordance with the calculation result of the area ratio, using the result of the machine learning.

Therefore, by performing the machine learning, it is possible to always grasp the stable emulsified state of the ink and reliably control the fountain water regardless of the experience and skill of the operator.

Further, without performing the machine learning, the dampening water may be controlled every time the area ratio is calculated to obtain an appropriate emulsified state of the ink.

In the embodiment shown in fig. 2, the reflected light detection device 31 is provided opposite to the plate cylinder 6, and the brightness of the reflected light 72 from the surface of the plate cylinder 6 is measured to detect the emulsified state of the ink in the plate cylinder 6.

For example, as shown in fig. 4, the reflected light detection device 31 may be provided opposite the ink roller 27, and the brightness of the reflected light 72 from the surface of the ink roller 27 may be measured to detect the emulsified state of the ink as the ink roller 27.

As shown in fig. 5, the reflected light detection device 31 may be provided opposite the ink oscillating roller 26, and the brightness of the reflected light 72 from the surface of the ink oscillating roller 26 may be measured to detect the emulsified state of the ink as the ink oscillating roller 26.

That is, the printing system of the present invention can be implemented not only in the plate cylinder 6 but also in a configuration in which the brightness of the reflected light 72 from the surface of any roller that supplies ink to the plate cylinder 6, such as the ink roller 27 and the ink swinging roller 26, is measured.

The measurement of the luminance of the reflected light 72 is not limited to one portion, and a plurality of reflected light detection devices 31 may be provided in one printing unit 5. For example, in addition to the detection of the reflected light 72 from the surface of the plate cylinder 6, a reflected light detection device 31 may be provided that detects the reflected light 72 from the surface of the ink roller 27.

As shown in fig. 3, the controller 56 detects the area ratio in the range where the luminance of the reflected light 72 described above is high, and further detects the following data as data for controlling the emulsified state of the ink, and controls the mechanical learning described later. Fig. 3 is a schematic diagram of a control system related to machine learning, and shows a control device 56 and an object to which data related to the printing system of the present invention is received and transmitted.

The control device 56 acquires information on the supply amount of dampening water at the start of printing, the supply amount of ink at the start of printing, and the printed pattern as information on the operating state of the offset rotary press 1.

Further, during execution of printing, the printing speed during printing (the rotation speed of the plate cylinder 6), the supply amount of dampening water during printing, and the supply amount of ink during printing are acquired as needed.

The control device 56 acquires detection information of the printing result as described below in order to check the emulsified state of the ink from the printing result.

The printing substrate W after printing is imaged by a dot detection device 41 provided between the printing unit 3 and the paper discharge unit 4, and the dot shape and dot area ratio of the result of printing are detected. When the emulsified state of the ink is not appropriate, deterioration of the dot shape and change in the dot area ratio occur. The dot shape and dot area ratio are detected at any time during printing, and are sent to the control device 56.

The control device 56 can analyze whether the change in dot shape and dot area ratio has changed from the appropriate state, and determine whether the emulsified state of the ink is appropriate. The criterion for determining whether or not the change in the dot shape and the dot area ratio is appropriate is determined based on machine learning described later.

When the control device 56 determines that the emulsified state of the ink is not appropriate, the control device changes the control model of the fountain solution by adding the area ratio in the range where the luminance of the reflected light 72 is high as described above.

The control device 56 acquires detection information of the print result as follows in order to check the ink density from the print result.

The printed pattern is imaged by a pattern inspection device 42 provided between the printing unit 3 and the paper discharge unit 4, and the ink density is detected. When the fountain water is supplied in a large amount and the ink is excessively emulsified, the ink concentration changes to be thin. The ink density is detected at any time during printing and is sent to the control device 56.

The controller 56 can analyze whether the ink density has changed from an appropriate state, and determine whether the emulsified state of the ink is appropriate. The determination as to whether the ink density is in an appropriate state is based on a mechanical learning determination criterion described later.

In the case where the ink density is inappropriate, the amount of ink supplied is controlled by the ink device 21.

In printing by the blanket wheel, it is known that the state of ink is affected by the temperature and humidity of the blanket wheel 1. Therefore, in order to accurately determine the emulsified state of the ink from the area ratio in the range where the luminance of the reflected light 72 is high, it is necessary to keep the temperatures of the fountain water and the ink constant.

Therefore, the controller 56 detects the dampening water temperature at the start of printing, the ink temperature at the start of printing, the water flow temperature of the swing roller at the start of printing, the water flow temperature of the plate cylinder at the start of printing, the temperature in the factory at the start of printing, and the humidity in the factory at the start of printing as information on the temperature and humidity of the offset rotary press 1.

During printing, the dampening water temperature during printing, the ink temperature during printing, the water feed temperature of the oscillating roller during printing, the water feed temperature of the plate cylinder during printing, the temperature in the factory during printing, and the humidity in the factory during printing are detected at any time.

The temperature and humidity in the plant can be measured by a known thermometer and hygrometer not shown. The thermometer and hygrometer can be installed at any position near the offset rotary press 1, such as on the upper side of the printing unit 5.

The controller 56 performs control to keep the temperatures of the dampening water and the ink constant based on the detected temperature and humidity. For example, when the temperature detected by the dampening water temperature detector 12 is different from a predetermined temperature, the dampening water cooling device 18 controls the temperature of the dampening water to be a predetermined temperature. When the temperature detected by the ink temperature detector 22 is different from a predetermined temperature, the temperature of the cooling water is controlled by the ink oscillating roller cooling water temperature controller 29 so as to be a predetermined temperature.

Next, control related to machine learning will be described.

In the printing system of the present invention, the control device 56 acquires data of the supply amount of dampening water at the start of printing, the supply amount of ink at the start of printing, information of the pattern to be printed, the printing speed during printing, the supply amount of dampening water during printing, and the supply amount of ink during printing as the operating state of the offset rotary press 1, in addition to the area ratio in the range where the luminance of the reflected light 72 is high; acquiring data of dot shape, dot area ratio and ink concentration detected from the printing result as detection information of the printing result of the offset rotary press; data of the dampening water temperature at the start of printing, the ink temperature at the start of printing, the water temperature of the dampening roller at the start of printing, the water temperature of the plate cylinder at the start of printing, the temperature in the factory at the start of printing, the humidity in the factory at the start of printing, the water temperature of the dampening roller during printing, the ink temperature during printing, the water temperature of the dampening roller during printing, the water temperature of the plate cylinder during printing, the temperature in the factory during printing, and the humidity in the factory during printing are acquired as information of the temperature and the humidity of the offset rotary press 1, and these data are transmitted to the cloud server 51 via the internet.

The cloud server 51 stores these data and performs machine learning. As a result of the machine learning, the cloud server 51 creates and updates a control model for controlling the fountain water in an appropriate emulsified state of ink and outputting the control of the ink in accordance with the received data.

For example, the controller 56 adjusts the supply amount and supply timing of the dampening water by controlling the rotation amounts of the fountain roller 14 and the metering roller 15 based on the updated control model outputted from the cloud server 51, and controls the fountain roller to maintain the emulsified state of the ink at an optimum level.

In addition to the above, the supply amount and supply timing of ink by controlling the rotation amount of the ink supply roller 24 may be adjusted.

The temperature of the dampening water in the water tray 13 is controlled by the dampening water cooling device 18, and the temperature of the ink is controlled by the ink oscillating roller cooling water temperature control device 29 so that the dampening water temperature and the ink temperature are kept constant.

The control may be performed for all of these, or may be performed by selecting any one of these.

The control may be performed automatically by the control device 56 in accordance with the output from the cloud server 51, or may be performed by an operator by notifying the operator of the output from the cloud server 51.

Therefore, when the operating state, the printing result, the temperature, and the humidity of the offset rotary press 1 change, the emulsified state of the ink can be always stably realized and the emulsified state of the ink can be appropriately controlled without depending on the experience and skill of the operator.

The system of the present invention may be controlled by the edge AI without using the cloud server 51. As an example of the control by the edge AI, the control device 56 performs machine learning by the cloud server 51. The control device 56 uses the detected data to create and update a control model in the control device 56. The controller 56 controls the dampening water and ink using the control model thus created.

In the case of control by the edge AI, compared to the case of using the cloud server 51, since it is not necessary to transmit and receive data to and from the cloud server 51, it is possible to avoid communication delay and to achieve high-speed processing.

The system of the present invention can also be controlled using a learned control model created by the machine learning performed by the cloud server 51 or the machine learning performed by the edge AI.

The controller 56 can apply the data detected by the controller 56 to the control model without performing machine learning, and can control the dampening water and the ink in accordance with the output result.

When the learned control model is used, the control can be performed even when the processing capability of the controller 56 is low.

Claims (13)

1. A printing system of an offset rotary press is characterized in that,

the offset rotary press comprises at least one printing unit,

the printing unit comprises a plate cylinder, a dampening water device for supplying dampening water to the plate cylinder, and an ink device for supplying ink to the plate cylinder,

an ink emulsion state detection unit including a light source for irradiating light to the surface of the plate cylinder and/or the surface of any one of the rollers of the ink device; a camera for shooting the reflected light reflected from the surface of the roller; and a control unit for binarizing the image captured by the camera into a range in which the brightness of the reflected light is high and a range in which the brightness of the reflected light is low, and calculating an area ratio of the range in which the brightness of the reflected light is high with respect to the entire area of the image captured by the camera,

when the area ratio of the range in which the luminance of the reflected light calculated by the control unit is high, the supply of the dampening water device is controlled so as to achieve an appropriate emulsified state of the ink.

2. The printing system of an offset rotary press according to claim 1,

the structure is as follows: the light source irradiates irradiation light of a specific wavelength, and the camera captures only reflected light of the specific wavelength.

3. The printing system of an offset rotary press according to claim 1,

the temperature of the dampening water supplied from the dampening water device and the temperature of the ink supplied from the ink device are kept constant.

4. The printing system of an offset rotary press according to claim 1,

the light source is a high color rendering LED.

5. The printing system of an offset rotary press according to claim 1,

the control unit repeatedly calculates and stores an area ratio in a range in which the luminance of reflected light is high during printing, mechanically learns a control model of dampening water in an emulsified state of appropriate ink in accordance with the stored area ratio, and updates the control model to the emulsified state of appropriate ink in accordance with the calculated area ratio.

6. The printing system of an offset rotary press according to claim 5,

the control module stores at least one or more of information of an operating state of the offset rotary press, detection information of a printing result, temperature, and humidity in addition to the area ratio, performs machine learning of the control model based on the stored area ratio and information of a store other than the area ratio, and updates the control model to a control model corresponding to the information.

7. The printing system of an offset rotary press according to claim 6,

the operating conditions of the offset rotary press include at least one of the supply amount of dampening water at the start of printing, the supply amount of ink at the start of printing, information on a printed pattern, the printing speed during printing, the supply amount of dampening water during printing, and the supply amount of ink during printing.

8. The printing system of an offset rotary press according to claim 6,

the detection information of the printing result includes at least one of a dot shape, a dot area ratio, and an ink density detected from the printing result.

9. The printing system of an offset rotary press according to claim 6,

the information on the temperature and humidity includes at least one of dampening water temperature at the start of printing, ink temperature at the start of printing, dampening water temperature at the swing roller at the start of printing, plate cylinder water temperature at the start of printing, temperature in the factory at the start of printing, humidity in the factory at the start of printing, dampening water temperature during printing, ink temperature during printing, swing roller water temperature during printing, plate cylinder water temperature during printing, temperature in the factory during printing, and humidity in the factory during printing.

10. The printing system of an offset rotary press according to claim 5 or 6,

the control model is updated on a cloud server independent of the offset rotary press.

11. The printing system of an offset rotary press according to claim 5 or 6,

the updating of the control model is performed by a control device in the offset printing rotary machine.

12. The printing system of an offset rotary press according to claim 5 or 6,

and controlling dampening water of the dampening water device by using the updated control model.

13. An offset rotary press comprising the printing system according to any one of claims 1 to 9.

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