JP2014124825A - Blanket cylinder cleaning device, blanket cylinder cleaning method and offset printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blanket cylinder cleaning device capable of reducing loss of ink solvent to be supplied on a surface of a blanket cylinder of an offset printer.SOLUTION: A blanket cylinder cleaning device 10 includes: a solvent supply mechanism 20 for, from each of supply ports 21 aligned in an axial direction of a blanket cylinder 2, supplying ink solvent 11 to a surface of the blanket cylinder; a recording unit 30 for recording at least one of information concerning axial direction distribution of a pattern area rate about patterns having been printed by an offset printer, and information concerning axial direction distribution of the amount of supply of ink; a control unit 40 for, on the basis of at least one of the information recorded in the recording unit 30, controlling the amount of supply of the ink solvent, from the respective supply ports of the solvent supply mechanism; and a transfer target holding mechanism 50 for pressing a transfer target 51 against the blanket cylinder, and making ink on the surface of the blanket cylinder dissolved by the ink solvent be transferred to the transfer target.

Description

  The present invention relates to a blanket cylinder cleaning apparatus and a blanket cylinder cleaning method for cleaning a blanket cylinder of an offset printing press. The present invention also relates to an offset printing machine provided with this blanket cylinder cleaning device.

  The offset printing machine usually has a plate cylinder that holds the ink supplied from the ink supply unit on the surface, and a plate cylinder that is disposed opposite to the plate cylinder and is pressed against the plate cylinder to hold the ink held on the plate cylinder on the surface. The pressure is transferred between the blanket cylinder to be transferred to the printing object and the blanket cylinder, which is arranged so as to face the blanket cylinder, sandwiching the conveyed printing object together with the blanket cylinder, and transferring the ink transferred to the surface of the blanket cylinder to the printing object. And a torso. As this offset printing machine is operated, stain components such as altered ink and paper dust gradually accumulate on the surface of the blanket cylinder. When a stain component is accumulated to some extent on the surface of the blanket cylinder, the stain component adheres to the printing object together with the ink, thereby degrading the print quality. Therefore, it is necessary to periodically clean the surface of the blanket cylinder to remove accumulated dirt components.

  In addition, when changing the pattern applied to the printing object, the plate wrapped around the surface of the plate cylinder is replaced and the surface of the blanket cylinder is washed to remove ink and accumulated dirt components. There is a need to.

  An apparatus for cleaning such a blanket cylinder is described in Patent Documents 1 to 3, for example. Among these, the blanket cylinder washing | cleaning apparatus described in patent document 1 is demonstrated with reference to FIG. FIG. 7 is a schematic side view showing the blanket cylinder cleaning device described in Patent Document 1. As shown in FIG. The blanket cylinder cleaning apparatus shown in FIG. 7 presses a sheet-like transferred material 551 toward the blanket cylinder 502 by pressing the sheet supply object 551 to the solvent supply mechanism 520 that supplies the ink dissolving agent 511 to the surface of the blanket cylinder 502, thereby dissolving the ink. A transfer object holding mechanism 550 having a plurality of nipping rollers 554 for transferring the ink dissolved on the surface of the blanket cylinder 502 to the transfer object 551 by the agent 511.

  When cleaning the surface of the blanket cylinder 502, the supply of ink to the plate cylinder of the offset printing machine is stopped, and then the ink dissolving agent 511 is supplied from the dissolving agent supply mechanism 520 to the surface of the blanket cylinder 502. Next, the transfer object 551 is pressed by the nipping roller 554 toward the surface of the blanket cylinder 502 supplied with the ink dissolving agent 511. Thereby, the ink on the surface of the blanket cylinder 502 dissolved by the ink dissolving agent 511 is transferred to the transfer object 551 and removed.

Patent No. 4945908 Specification Japanese Patent No. 4859023 Special table 2012-506784 gazette

  By the way, the stain components deposited on the surface of the blanket cylinder are mainly residues such as denatured ink and paper dust carried by the ink and remaining on the surface of the blanket cylinder. For this reason, if the amount of ink supplied to each region changes along the axial direction of the blanket cylinder 502, the amount of stain components deposited in each region also varies along the axial direction of the blanket cylinder 502. That is, in a region where the amount of ink supplied is large in each region along the axial direction of the blanket cylinder 502, the amount of stain components deposited in the region also increases. On the other hand, in the region where the amount of ink supplied is small among the regions along the axial direction of the blanket cylinder 502, the amount of stain components deposited in the region is also small.

  On the other hand, the ink supplied to the surface of the blanket cylinder 502 is transferred from the ink supply section of the offset printing machine via the plate cylinder. The ink supplied from the ink supply unit to the surface of the plate cylinder is determined according to the axial distribution of the pattern area ratio. Usually, since the axial distribution of the pattern area ratio is not constant, the amount of ink supplied from the ink supply unit to the surface of the plate cylinder is different for each region along the axial direction of the plate cylinder. If the amount of ink supplied for each region along the axial direction of the plate cylinder is different, the amount of ink supplied for each region along the axial direction of the blanket cylinder 502 is also different. . As a result, the amount of dirt components adhering to the blanket cylinder 502 also varies along the axial direction of the blanket cylinder 502. For example, when a large amount of ink is supplied to one of the regions along the axial direction of the plate cylinder, ink is supplied to a region along the axial direction of the blanket cylinder 502 facing the region of the plate cylinder. As a result, the amount of dirt components deposited on the blanket cylinder 502 in the region increases.

  However, the conventional blanket cylinder cleaning apparatus does not consider the distribution of dirt components in the axial direction of the blanket cylinder 502, and supplies the ink dissolving agent 511 with the supply amount constant along the axial direction of the blanket cylinder 502. Was. For this reason, although the amount of the stain component is small in a certain region along the axial direction of the blanket cylinder 502, the excess ink dissolving agent 511 is supplied to the region, and the loss of the ink dissolving agent 511 is large. .

  Nowadays, there are a wide variety of pattern patterns applied to a print object, and there is a great expectation for stable print quality. For this reason, the frequency of cleaning the blanket cylinder is increasing more and more, and a technique for cleaning the blanket cylinder more efficiently is desired.

  The present invention has been made in view of these points, and an object of the present invention is to provide a blanket cylinder cleaning device capable of reducing the loss of the ink dissolving agent supplied to the surface of the blanket cylinder.

The blanket cylinder cleaning device according to the present invention is a plate cylinder and an ink supply unit that supplies ink to the surface of the plate cylinder, and adjusts the supply amount of the ink according to the position along the axial direction of the plate cylinder. Cleaning for cleaning the blanket cylinder of an offset printing press comprising a possible ink supply part and a blanket cylinder arranged opposite to the plate cylinder and to which the ink supplied to the plate cylinder is transferred to the surface A device,
A plurality of supply ports arranged in the axial direction of the blanket cylinder, a dissolving agent supply mechanism for supplying an ink dissolving agent from each supply port to the surface of the blanket cylinder;
A recording unit that records at least one of information on the axial distribution of the pattern area ratio of the image printed by the offset printing machine and information on the axial distribution of the amount of ink supplied from the ink supply unit When,
Based on at least one of the information on the axial distribution of the pattern area ratio recorded on the recording unit and the information on the axial distribution of the amount of ink supplied from the ink supply unit, the dissolution agent supply mechanism A control unit for controlling the supply amount of the ink dissolving agent from each supply port;
A transfer object holding mechanism for pressing the transfer object to which the ink on the surface of the blanket cylinder dissolved by the ink dissolving agent is transferred, toward the blanket cylinder;
Is provided.

In the blanket cylinder cleaning apparatus according to the present invention, the transfer object holding mechanism is
A transferred object feeding portion for feeding the sheet-shaped transferred object;
A transfer object collecting unit for collecting the sheet-like transfer object fed from the transfer object feeding unit;
A nipping roller that is disposed to face the blanket cylinder and presses the transferred object before being transferred from the transferred object supply part and recovered by the transferred object recovery part toward the blanket cylinder;
You may have.

  In the blanket cylinder cleaning apparatus according to the present invention, the pressing by the nipping roller is performed intermittently, and when the transfer object is not pressed by the nipping roller, the transfer object is transferred from the transfer object feeding portion. It may be fed out and collected in the transferred object collecting unit.

  In the blanket cylinder cleaning apparatus according to the present invention, the recording unit also records information related to a printing time printed by the offset printing press, and the control unit also records information related to the printing time recorded in the recording unit. Based on this, the supply amount of the ink dissolving agent may be controlled.

In the blanket cylinder cleaning device according to the present invention, the ink supply unit includes:
An ink fountain in which ink is stored;
An ink base roller supplied with ink from the ink fountain;
Have
The ink fountain includes a plurality of ink keys arranged in the axial direction of the ink base roller,
Each ink key can adjust the amount of ink supplied to the ink source roller by adjusting the ink key opening, which is the gap amount between the ink source roller, independently of the other ink keys. And
The ink key opening degree of each ink key may be recorded in the recording unit as information regarding the axial distribution of the amount of ink supplied from the ink supply unit.

An offset printing press according to the present invention comprises a plate cylinder,
An ink supply unit for supplying ink to the surface of the plate cylinder, the ink supply unit being capable of adjusting the supply amount of the ink according to the position along the axial direction of the plate cylinder;
A blanket cylinder that is arranged opposite to the plate cylinder and in which the ink supplied to the plate cylinder is transferred to the surface;
A blanket cylinder cleaning device having any one of the above characteristics;
Is provided.

The blanket cylinder cleaning method according to the present invention includes a plate cylinder and an ink supply unit that supplies ink to the surface of the plate cylinder, and the supply amount of the ink is adjusted according to a position along the axial direction of the plate cylinder. Cleaning for cleaning the blanket cylinder of an offset printing press comprising a possible ink supply part and a blanket cylinder arranged opposite to the plate cylinder and to which the ink supplied to the plate cylinder is transferred to the surface A method,
A step of recording at least one of information on the axial distribution of the pattern area ratio of the image printed by the offset printing machine and information on the axial distribution of the amount of ink supplied from the ink supply unit;
Based on at least one of the recorded information on the axial distribution of the pattern area ratio and the information on the axial distribution of the amount of ink supplied from the ink supply unit, the blanket cylinders are arranged in the axial direction. A step of supplying an ink dissolving agent controlled to a desired amount to the surface of the blanket cylinder from each supply port;
With
In the step of supplying the ink dissolving agent to the surface of the blanket cylinder, the object to be transferred is pressed toward the surface of the blanket cylinder supplied with the ink dissolving agent, and the ink dissolving agent is dissolved by the ink dissolving agent. Ink on the surface of the blanket cylinder is transferred to the transfer object.

In the blanket cylinder cleaning method according to the present invention, the transfer object is in a sheet form, and is transferred from the transfer object supply part and recovered by the transfer object recovery part.
In the step of supplying the ink dissolving agent to the surface of the blanket cylinder, the pressing by the nipping roller is performed intermittently,
When the transfer object is not pressed by the nipping roller, the transfer object may be fed out from the transfer object feeding unit and collected in the transfer object collecting unit.

  According to the present invention, it is possible to reduce the loss of the ink dissolving agent supplied to the surface of the blanket cylinder.

FIG. 1 is a schematic side view showing an example of an offset printing press provided with a blanket cylinder cleaning device according to an embodiment of the present invention. FIG. 2 is a schematic side view showing a blanket cylinder cleaning apparatus according to an embodiment of the present invention. FIG. 3 is a schematic plan view showing the dissolving agent supply mechanism shown in FIG. FIG. 4 shows a blanket cylinder in which dirt components are sufficiently accumulated when the supply amount of the ink dissolving agent supplied from one supply port is changed in order for each test and the blanket cylinder cleaning device is operated for a predetermined time. It is a graph which shows the result of having investigated the removal amount of the soil component removed from. FIG. 5 is a flowchart for explaining the operation of the control unit. FIG. 6 is a schematic plan view corresponding to FIG. 3 and showing another example of the dissolving agent supply mechanism. FIG. 7 is a schematic side view showing the blanket cylinder cleaning device described in Patent Document 1. As shown in FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual product.

  1 to 4 are diagrams for explaining an embodiment according to the present invention. Among these, FIG. 1 is a schematic side view showing an example of an offset printing machine.

  First, an offset printing machine 1 having a blanket cylinder 2 to be cleaned using a blanket cylinder cleaning apparatus 10 according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, an offset printing machine 1 is disposed opposite to a plate cylinder 3, an ink supply unit 4 that supplies ink to the surface of the plate cylinder 3, and the plate cylinder 3. A blanket cylinder 2 on which the ink that is pressed and supplied to the plate cylinder 3 is transferred to the surface is provided, and an impression cylinder 8 that is disposed to face the blanket cylinder 2. The conveyed printing object W is sandwiched between the impression cylinder 8 and the plate cylinder 3, and the transferred ink is transferred to the surface of the plate cylinder 3.

  First, the ink supply unit 4 will be described. As shown in FIG. 1, the ink supply unit 4 includes an ink fountain 5 in which ink is stored, and an ink source roller 6 to which ink is supplied from the ink fountain 5. In the present embodiment, an organic solvent-based ink is used as the ink.

  As a specific configuration, the ink fountain 5 is arranged in the axial direction of the ink base roller 6 and the inclined bottom surface 5a that inclines downward as it approaches the ink base roller 6 from the horizontal direction. And a pair of side surfaces (not shown) facing the ink source roller 6 in the axial direction. Ink is stored in a space defined by the inclined bottom surface 5 a, the plurality of ink keys 7, a pair of side surfaces, and a part of the outer peripheral surface of the ink base roller 6.

  The ink stored in the ink fountain 5 is supplied from the gap between the ink key 7 and the ink base roller 6 to the surface of the rotating ink base roller 6. Each ink key 7 can individually adjust the ink key opening, which is a gap amount between the ink base roller 6, independently of the other ink keys 7. Therefore, by individually adjusting the ink key opening degree of each ink key 7, the amount of ink supplied to the surface of the ink source roller 6 can be adjusted at each position along the axial direction of the ink source roller 6. . That is, for each ink key 7, a region where the ink supply amount can be individually adjusted is defined along the axial direction of the ink base roller 6.

  An ink roller group 9 including a plurality of ink rollers is arranged between the ink base roller 6 and the plate cylinder 3. The ink supplied to the surface of the ink base roller 6 is sequentially transferred to a plurality of ink rollers of the ink roller group 9 and supplied to the plate cylinder 3.

  On the other hand, dampening water is also supplied to the plate cylinder 3 from the dampening water supply unit 91. The dampening water supply unit 91 includes a water boat 92 in which dampening water is stored, and a dampening water source roller 93 that draws dampening water from the water boat 92 and holds the dampening water on the surface. Have. A dampening water roller group 94 including a plurality of dampening water rollers is arranged between the dampening water source roller 93 and the plate cylinder 3. The dampening water pumped up from the water boat 92 and held on the surface of the dampening water source roller 93 is sequentially transferred to the plurality of ink rollers of the dampening water roller group 94 and supplied to the plate cylinder 3. ing.

  Next, the plate cylinder 3 will be described. A plate is wound around the surface of the plate cylinder 3, and a pattern of the pattern is recorded on this plate. Specifically, a lipophilic part and a hydrophilic part are defined on the plate, and among these, the lipophilic part corresponds to the pattern. The dampening water is first supplied to the plate from the dampening water supply unit 91, and the dampening water is held in the hydrophilic portion of the plate. Next, ink is supplied from the ink supply unit 4 to the plate, and the ink repels dampening water held in the hydrophilic portion of the plate and is appropriately emulsified in the dampening water. Retained in the lipophilic part. Then, the ink held in the oleophilic portion of the plate is transferred to the surface of the blanket cylinder 2 in contact with the plate cylinder 3 and transferred from the blanket cylinder 2 to the printing object W.

  In the present embodiment, the supply amount of ink supplied from the ink supply unit 4 according to the axial distribution P of the pattern area ratio indicating the proportion of the surface corresponding to the pattern pattern on the surface of the plate cylinder 3. Is determined at each position along the axial direction of the plate cylinder 3. In the present specification, an ink supply amount supplied from the ink supply unit 4 as a distribution at each position along the axial direction of the plate cylinder 3 is referred to as an axial distribution Q of the ink supply amount.

  Specifically, the supply of ink supplied to the ink source roller 6 is determined by appropriately determining the ink key opening degree of each ink key 7 arranged in the axial direction of the ink source roller 6 independently of the other ink keys 7. The amount of ink supplied is adjusted at each position along the axial direction of the plate cylinder 3 by adjusting the amount.

  Next, a blanket cylinder cleaning apparatus 10 for cleaning the blanket cylinder 2 of the offset printing machine 1 will be described with reference to FIG. FIG. 2 is a schematic side view showing the blanket cylinder cleaning apparatus 10 according to one embodiment of the present invention. As shown in FIG. 2, the blanket cylinder cleaning apparatus 10 has a plurality of supply ports 21 arranged in the axial direction of the blanket cylinder 2, and supplies the ink dissolving agent 11 to the surface of the blanket cylinder 2 from each supply port 21. Information regarding the axial distribution P of the pattern area ratio of the dissolving agent supply mechanism 20 and the pattern printed by the offset printer 1, and the axial distribution Q of the amount of ink supplied from the ink supply unit 4 The amount of ink dissolving agent 11 supplied from each supply port 21 of the dissolving agent supply mechanism 20 based on at least one of the information recorded on the recording unit 30 and at least one of the information recorded on the recording unit 30 The control unit 40 for controlling the ink and the object to be transferred 51 are pressed toward the blanket cylinder 2 and the ink on the surface of the blanket cylinder 2 dissolved by the ink dissolving agent 11 is transferred. It includes a transfer target holding mechanism 50, a to transfer to 51. Hereinafter, each component will be described in detail.

  First, the dissolving agent supply mechanism 20 will be described with reference to FIG. FIG. 3 is a schematic plan view showing the dissolving agent supply mechanism 20 shown in FIG. As shown in FIG. 3, the dissolving agent supply mechanism 20 includes a dissolving agent storage unit 22 in which the ink dissolving agent 11 is stored, a pump 23 that pumps ink from the dissolving agent storage unit 22, and ink pumped from the pump 23. And an intermediate portion 24 for guiding the dissolving agent 11 to the supply ports 21. Among these, the intermediate part 24 is comprised by the flat plate-shaped or rod-shaped member arrange | positioned facing the blanket cylinder 2, The melt | dissolution which guides the ink dissolving agent 11 pumped up from the pump 23 inside the said member An agent supply path 25 is defined. The intermediate portion 24 supports the supply ports 21 arranged in the axial direction of the blanket cylinder 2, and the dissolving agent supply path 25 of the intermediate portion 24 communicates with the supply ports 21.

  A corresponding valve 26 is provided for each supply port 21. Each valve 26 can block part or all of the flow path in the dissolving agent supply path 25 on the upstream side in the vicinity of the corresponding supply port 21. Thereby, the supply amount of the ink dissolving agent 11 guided to each supply port 21 can be adjusted. Each valve 26 is controlled by a control unit 40 described later. But the means to adjust the supply amount of the ink dissolving agent 11 guided to each supply port 21 is not limited to such an example. As another example, the inner diameter of each supply port can be adjusted, and the supply amount of the ink dissolving agent 11 supplied from each supply port can be adjusted by adjusting the inner diameter of each supply port. It may be.

  As described above, the supply ports 21 are arranged in the axial direction of the blanket cylinder 2, and the supply amount of the ink dissolving agent 11 supplied from the supply ports 21 to the surface of the blanket cylinder 2 is adjusted by the valve 26. Can do. By individually adjusting each valve 26 independently of the other valves 26, the supply amount of the ink dissolving agent 11 supplied to the surface of the blanket cylinder 2 is supplied to the supply port 21 along the axial direction of the blanket cylinder 2. Individual adjustments can be made at each corresponding position. That is, for each supply port 21, a region where the supply amount of the ink dissolving agent 11 can be individually adjusted is defined along the axial direction of the blanket cylinder 2. In this embodiment, an organic solvent-based ink dissolving agent is used as the ink dissolving agent 11.

  Next, the recording unit 30 will be described. The recording unit 30 of the present embodiment includes an acquisition unit 31 that acquires at least one of information on the axial distribution P of the pattern area ratio and information on the axial distribution Q of the ink supply amount, and the acquisition unit 31 Recording means 32 for recording the acquired information. In the present embodiment, the ink key opening degree of each ink key 7 is recorded in the recording unit 30 as information regarding the axial distribution Q of the amount of ink supplied from the ink supply unit 4.

  The recording unit 30 can also record information related to the printing time T during which the offset printer was printing. Specifically, the acquisition unit 31 acquires information related to the printing time T printed by the offset printing press before cleaning. Then, information relating to the printing time T acquired by the acquisition unit 31 is recorded by the recording unit 32.

  The acquisition means 31 can acquire information on the axial distribution P of the pattern area ratio and information on the axial distribution Q of the ink supply amount by inputting necessary information by an operator as an example. Alternatively, by receiving necessary information from a control unit (not shown) of the offset printing press 1, information on the axial distribution P of the pattern area ratio and information on the axial distribution Q of the ink supply amount can be acquired. You may do it. On the other hand, as an example, the recording unit 32 may separately record these pieces of information according to the pattern.

  Next, the control unit 40 that controls the dissolving agent supply mechanism 20 based on the information recorded in the recording unit 30 will be described. The control unit 40 is based on at least one of the information related to the axial distribution P of the pattern area ratio and the information related to the axial distribution Q of the amount of ink supplied from the ink supply unit 4 recorded in the recording unit 30. The supply amount of the ink dissolving agent 11 from each supply port 21 of the dissolving agent supply mechanism 20 is controlled. Further, the control unit 40 controls the supply amount of the ink dissolving agent 11 based on the information regarding the printing time T recorded in the recording unit 30.

As described above, in each region along the axial direction of the blanket cylinder 2, in the region where the ink supply amount X is large, the amount of stain components deposited in the region also increases. On the other hand, in each region along the axial direction of the blanket cylinder 2, in the region where the ink supply amount X is small, the amount of stain components deposited in the region is also small. Further, the amount of dirt components deposited on the blanket cylinder 2 gradually increases with the printing time T. As a result of extensive research conducted by the present inventors, the stain component accumulated in each region along the axial direction of the blanket cylinder 2 is approximately proportional to the amount X of ink supplied to the region and the printing time T. It was discovered. That is, the following relational expression (a) is established.
(Amount of stain component accumulated in each region along the axial direction of the blanket cylinder 2) ∝ (Supply amount X of ink supplied to the region) × (printing time T) (a)

Further, as described above, the ink supply amount X supplied to each region along the axial direction of the blanket cylinder 2 corresponds to the ink supply amount supplied to each region along the axial direction of the plate cylinder 3. To do. The amount of ink supplied to each region along the axial direction of the plate cylinder 3 is determined according to the axial distribution P of the pattern area ratio. Specifically, the amount of ink supplied to each region along the axial direction of the plate cylinder 3 is proportional to the pattern area ratio Y of the region. Therefore, the stain component deposited in each region along the axial direction of the blanket cylinder 2 is approximately proportional to the pattern area ratio Y and the printing time T of the region. That is, the following relational expression (b) is established.
(Amount of dirt component deposited in each region along the axial direction of the blanket cylinder 2) ∝ (pattern area ratio Y of the region) × (printing time T) (b)

  Furthermore, when the relationship between the stain component removal rate and the supply amount of the ink dissolving agent 11 was investigated, the relationship shown in the graph of FIG. 4 was obtained. FIG. 4 shows that when the supply amount of the ink dissolving agent 11 supplied from one supply port 21 is changed in order for each test and the blanket cylinder cleaning device 10 is operated for a predetermined time, the stain component is sufficiently accumulated. It is a graph which shows the result of having investigated the removal amount of the dirt component removed from the blanket cylinder 2 which was done. In the graph shown in FIG. 4, the vertical axis represents the removal amount of the stain component, and the horizontal axis represents the supply amount of the ink dissolving agent 11. As shown in the graph of FIG. 4, when the supply amount of the ink dissolving agent 11 is gradually increased from the state where the ink dissolving agent 11 is not supplied, the removal amount of the stain component is also increased accordingly. More specifically, the removal amount of the stain component increases in proportion to the supply amount of the ink dissolving agent 11. On the other hand, when the supply amount of the ink dissolving agent 11 exceeds a predetermined amount, the removal amount of the stain component does not change even if the supply amount of the ink dissolving agent 11 is further increased. That is, when the supply amount of the ink dissolving agent 11 exceeds a predetermined amount, the amount exceeding the predetermined amount is merely supplied excessively, and does not effectively act to remove the stain component. As shown in the graph of FIG. 4, this predetermined amount is defined as the transition supply amount, and the removal amount of the stain component when the supply amount of the ink dissolving agent 11 is defined as the transition supply amount is defined as the transition stain component removal amount.

Based on this knowledge, the supply amount of the ink dissolving agent 11 can be determined from the amount of accumulated dirt components. Specifically, when the amount of accumulated dirt component is smaller than the transition dirt component removal amount, as can be understood from the graph of FIG.
(Supply amount of ink dissolving agent 11) ∝ (Amount of accumulated dirt component) (c)
If the supply amount of the ink dissolving agent 11 is determined as described above, the accumulated dirt component can be removed when the blanket cylinder cleaning device 10 is operated for a predetermined time. On the other hand, when the amount of the accumulated stain component becomes larger than the removal amount of the transition stain component, even if the supply amount of the ink dissolving agent 11 is larger than the transition supply amount, as shown in the graph of FIG. The removal amount does not change. Therefore, in order not to supply the ink dissolving agent 11 excessively,
(Supply amount of ink dissolving agent 11) = (Transition supply amount) (d)
The supply amount of the ink dissolving agent 11 can be determined as follows. In addition, in order to remove all dirt components, it is necessary to lengthen the operation time of the blanket cylinder cleaning apparatus 10.

  Based on such knowledge, based on at least one of the information on the axial distribution P of the pattern area ratio and the information on the axial distribution Q of the amount of ink supplied from the ink supply unit 4, the solubilizer supply mechanism 20 The control which optimally determines the supply amount of the ink dissolving agent 11 from each supply port 21 was found. Hereinafter, the control of the control unit 40 will be described in detail with reference to the flowchart shown in FIG.

  As shown in FIG. 5, the control unit 40 first calculates the amount of dirt components accumulated in each region along the axial direction of the blanket cylinder 2 based on the information recorded in the recording unit 30. (STEP 1). Specifically, the supply amount of ink supplied through each ink key 7 is calculated from the ink key opening degree of each ink key 7 recorded in the recording unit 30. Subsequently, based on the formula (a), the product of the supply amount of the ink supplied through each ink key 7 and the printing time T is obtained, and along the axial direction of the blanket cylinder 2 corresponding to each ink key 7. The amount of dirt component deposited in each region is calculated. Next, the arrangement of the ink keys 7 and the arrangement of the supply ports 21 along the axial direction are compared, and the supply port 21 is determined from the distribution of the stain components along the axial direction of the blanket cylinder 2 with reference to the arrangement of the ink keys 7. Is converted into a distribution of dirt components along the axial direction of the blanket cylinder 2. That is, the amount of accumulated dirt components is calculated for each region corresponding to each supply port 21.

  Alternatively, the pattern area ratio of the area along the axial direction of the blanket cylinder 2 corresponding to each supply port 21 is acquired from the axial distribution P of the pattern area ratio, and the pattern area of the area is obtained based on the formula (b). From the product of the rate and the printing time T, the amount of dirt components accumulated in the area may be calculated.

  Next, the control unit 40 determines the supply amount of the ink dissolving agent 11 from the corresponding supply port 21 from the amount of the dirt component accumulated in each region along the axial direction of the blanket cylinder 2 (STEP 2). Specifically, first, the amount of dirt components accumulated in each region is compared with the amount of transition dirt components removed. When the amount of the stain component accumulated in each region is smaller than the transition stain component removal amount, the supply amount of the ink dissolving agent 11 supplied from the corresponding supply port 21 is set in the region based on the equation (c). Determined in proportion to the amount of dirt components deposited. On the other hand, when the amount of the stain component accumulated in each region is larger than the transition stain component removal amount, the supply amount of the ink dissolving agent 11 supplied from the corresponding supply port 21 is calculated based on the equation (d). The transition supply amount is determined.

  Subsequently, the corresponding valve 26 is adjusted so that the supply amount of the ink dissolving agent 11 from each supply port 21 becomes the calculated amount (STEP 3). Thereby, the supply amount of the ink dissolving agent 11 supplied from the supply ports 21 to the surface of the blanket cylinder 2 is controlled by the control unit 40.

  Next, the transferred object holding mechanism 50 that presses the transferred object 51 toward the blanket cylinder 2 and transfers the ink and stain components on the surface of the blanket cylinder 2 to the transferred object 51 will be described. The transferred object holding mechanism 50 presses the transferred object 51 toward the blanket cylinder 2 and removes ink and stain components on the surface of the blanket cylinder 2 dissolved by the ink dissolving agent 11. As the transfer object 51, an object to be transferred that has been used in a conventional blanket cylinder cleaning apparatus can be used. As an example, a resin sheet such as cloth or polyethylene terephthalate can be used as the transfer object 51.

  As shown in FIG. 2, the transferred object holding mechanism 50 has, as a specific configuration, a transferred object feeding part 52 that feeds a sheet-like transferred object 51, and a sheet that is fed from the transferred object feeding part 52. Transfer object collecting unit 53 for collecting the object to be transferred 51 and the transfer object before being transferred to the transfer object collecting part 53 from the transfer object feeding part 52. A nipping roller 54 that presses the object 51 toward the blanket cylinder 2.

  In the present embodiment, the pressing by the nipping roller 54 is performed intermittently. When cleaning the blanket cylinder 2, the blanket cylinder 2 rotates in a state where the transfer object 51 is pressed against the blanket cylinder 2 by the nipping roller 54, and the ink and stain components on the surface of the blanket cylinder 2 are removed. It is rubbed and transferred to the transfer object 51. At this time, the transferred object feeding unit 52 and the transferred object collecting unit 53 are stopped. On the other hand, if ink and stain components are deposited to some extent on the sheet-like transfer object 51, further ink and stain components are difficult to transfer to the sheet-like transfer object 51. Need to slide. In the present embodiment, the state where the sheet-like transferred object 51 is pressed against the blanket cylinder 2 is released, and the sheet-like transferred object 51 is drawn out from the transferred object feeding part 52 to be transferred. The sheet-like transfer object 51 is slid by being collected by 53.

  Next, the operation of the present embodiment configured as described above will be described with reference to FIG.

  In the blanket cylinder cleaning method according to the present embodiment, information on the axial distribution P of the pattern area ratio for the pattern printed by the offset printing machine 1 and the axial distribution of the amount of ink supplied from the ink supply unit 4 are used. At least one of the step of recording at least one of information on Q, the recorded information on the axial distribution P of the pattern area ratio, and the information on the axial distribution Q of the amount of ink supplied from the ink supply unit 4 And the step of supplying the ink dissolving agent 11 controlled to a desired amount to the surface of the blanket cylinder 2 from the supply ports 21 arranged in the axial direction of the blanket cylinder 2. In the process of supplying the ink dissolving agent 11 to the surface of the blanket cylinder 2, the transfer object 51 is pressed toward the surface of the blanket cylinder 2 to which the ink dissolving agent 11 is supplied and dissolved by the ink dissolving agent 11. The ink on the surface of the blanket cylinder 2 is transferred to the transfer object 51.

  Specifically, first, at least the information regarding the axial distribution P of the pattern area ratio printed by the offset printing machine 1 before the cleaning and the information regarding the axial distribution Q of the ink supply amount are recorded. One is acquired by the acquisition means 31. Information acquired by the acquisition unit 31 is recorded in the recording unit 32 of the recording unit 30. In the present embodiment, the ink key opening degree of each ink key 7 is recorded in the recording unit 30 as information regarding the axial distribution Q of the amount of ink supplied from the ink supply unit 4. Further, the recording unit 30 also acquires the information related to the printing time T printed by the offset printer 1 before cleaning by the acquisition unit 31 and records the information in the recording unit 32.

  Next, based on the information recorded in the recording unit 30, the ink dissolving agent 11 controlled to a desired amount is supplied to the surface of the blanket cylinder 2 from each supply port 21. Specifically, at least the information regarding the axial distribution P of the pattern area ratio and the information regarding the axial distribution Q of the amount of ink supplied from the ink supply unit 4 recorded in the recording unit 30 by the control unit 40. Based on one side, the supply amount of the ink dissolving agent 11 from each supply port 21 of the dissolving agent supply mechanism 20 is controlled. At this time, the control unit 40 controls the supply amount of the ink dissolving agent 11 based also on the information related to the printing time T recorded in the recording unit 30.

  More specifically, as shown in FIG. 4, the control unit 40 first determines the amount of dirt components accumulated in each region along the axial direction of the blanket cylinder 2 based on the information recorded in the recording unit 30. Calculate (STEP 1). Specifically, the supply amount of ink supplied through each ink key 7 is calculated from the ink key opening degree of each ink key 7 recorded in the recording unit 30. Subsequently, based on the formula (a), the product of the supply amount of the ink supplied through each ink key 7 and the printing time T is obtained, and along the axial direction of the blanket cylinder 2 corresponding to each ink key 7. The amount of dirt component deposited in each region is calculated. Next, the arrangement of the ink keys 7 and the arrangement of the supply ports 21 along the axial direction are compared, and the supply port 21 is determined from the distribution of the stain components along the axial direction of the blanket cylinder 2 with reference to the arrangement of the ink keys 7. Is converted into a distribution of dirt components along the axial direction of the blanket cylinder 2. That is, the amount of accumulated dirt components is calculated for each region corresponding to each supply port 21.

  Alternatively, the pattern area ratio of the area along the axial direction of the blanket cylinder 2 corresponding to each supply port 21 is acquired from the axial distribution P of the pattern area ratio, and the pattern area of the area is obtained based on the formula (b). From the product of the rate and the printing time T, the amount of dirt components accumulated in the area may be calculated.

  Next, the control unit 40 determines the supply amount of the ink dissolving agent 11 from the corresponding supply port 21 from the amount of the dirt component accumulated in each region along the axial direction of the blanket cylinder 2 (STEP 2). Specifically, first, the amount of dirt components accumulated in each region is compared with the amount of transition dirt components removed. When the amount of the stain component accumulated in each region is smaller than the transition stain component removal amount, the supply amount of the ink dissolving agent 11 supplied from the corresponding supply port 21 is set in the region based on the equation (c). Determined in proportion to the amount of dirt components deposited. On the other hand, when the amount of the stain component accumulated in each region is larger than the transition stain component removal amount, the supply amount of the ink dissolving agent 11 supplied from the corresponding supply port 21 is calculated based on the equation (d). The transition supply amount is determined.

  Subsequently, the opening degree of the valve 26 corresponding to the supply port 21 is adjusted by the control unit 40 so that the supply amount of the ink dissolving agent 11 from each supply port 21 becomes the calculated amount (STEP 3). Thereby, the supply amount of the ink dissolving agent 11 supplied from the supply ports 21 to the surface of the blanket cylinder 2 is controlled by the control unit 40.

  Next, the transferred object holding mechanism 50 presses the sheet-shaped transferred object 51 toward the surface of the blanket cylinder 2 supplied with the ink dissolving agent 11. As a result, the ink and stain components on the surface of the blanket cylinder 2 dissolved by the ink dissolving agent 11 are transferred to the sheet-shaped transfer object 51. At this time, the ink and the stain component on the surface of the blanket cylinder 2 are removed by the sheet-shaped transfer object 51 in accordance with the supply amount of the ink dissolving agent 11. That is, a large amount of ink and stain components deposited on the surface of the blanket cylinder 2 are removed in areas where the supply amount of the ink dissolving agent 11 is large among the areas along the axial direction of the blanket cylinder 2. On the other hand, in areas where the supply amount of the ink dissolving agent 11 is small among the areas along the axial direction of the blanket cylinder 2, relatively little ink and stain components accumulated on the surface of the blanket cylinder 2 are removed.

  Thereafter, when ink and stain components are deposited to some extent on the sheet-like transfer object 51, further ink and stain components are hardly transferred to the sheet-like transfer object 51, and thus the sheet-like transfer object 51 is transferred. Need to slide. In the present embodiment, the state where the sheet-like transferred object 51 is pressed against the blanket cylinder 2 is released, and the sheet-like transferred object 51 is drawn out from the transferred object feeding part 52 to be transferred. By collecting by 53, the sheet-like transfer object 51 is slid.

  After the sheet-like transfer object 51 is slid, the ink dissolving agent 11 controlled to a desired amount is again supplied from the supply ports 21 to the surface of the blanket cylinder 2, so that the sheet-like transfer object 51 is transferred. Pressed against the surface of the blanket cylinder 2. As a result, the ink and stain components on the surface of the blanket cylinder 2 dissolved by the ink dissolving agent 11 are transferred to the sheet-shaped transfer target 51. By repeating such an operation, after cleaning for a certain period of time, the ink and stain components deposited on the surface of the blanket cylinder 2 are uniformly removed along the axial direction of the blanket cylinder 2.

  As described above, according to the present embodiment, the blanket cylinder is obtained from at least one of the information P related to the axial distribution of the pattern area ratio and the information Q related to the axial distribution of the amount of ink supplied from the ink supply unit 4. It is possible to predict the amount of dirt components that accumulate in each region along the two axial directions. Then, the supply amount of the ink dissolving agent 11 supplied from the supply ports 21 arranged in the axial direction of the blanket cylinder 2 is optimized based on the amount of dirt components accumulated in each region along the axial direction of the blanket cylinder 2. Can be determined. Then, the ink dissolving agent 11 controlled to a desired amount by the control unit 40 can be supplied to the surface of the blanket cylinder 2 from each supply port 21. For this reason, it is possible to effectively suppress the excessive ink dissolving agent 511 from being supplied to a region where the amount of accumulated dirt components is small in each region along the axial direction of the blanket cylinder 502. As a result, The loss of the ink dissolving agent 11 can be reduced.

  For example, it is assumed that six ink keys 7 are arranged in the axial direction of the ink base roller 6 and three supply ports 21 are arranged in the axial direction of the blanket cylinder 2. In this case, the area along the axial direction of the blanket cylinder 2 corresponding to the two ink keys 7 coincides with the area along the axial direction of the blanket cylinder 2 corresponding to one supply port 21. When the ink key opening degree of each ink key 7 is 10: 30: 60: 40: 80: 70 from one side of the ink base roller 6 to the other side, the region along the axial direction of the blanket cylinder 2 corresponding to each ink key 7 The amount of dirt components deposited on the surface is calculated as 10: 30: 60: 40: 80: 70 based on the formula (a). As described above, since the area corresponding to the two ink keys 7 coincides with the area corresponding to one supply port 21, the amount of stain components accumulated in the area corresponding to each supply port 21 is equal to two adjacent ink keys. 7 is the sum of the amount of dirt components deposited in the region corresponding to 7, which is 40: 100: 150. In this case, if the amount of stain components accumulated in each region is equal to or less than the transition stain component removal amount, the supply amount of the ink dissolving agent 11 supplied from each supply port 21 is 40: 100: 150 in order. On the other hand, in the conventional cleaning method, the supply amount of the ink dissolving agent 11 that can remove 80% of the stain component relative to the removal amount of the transition stain component is supplied from the three supply ports 21. If this supply amount is equal to the supply amount from the third supply port 21, the supply amount of the ink dissolving agent 11 of (1-40 / 150) × 100% = 73% is saved at the first supply port 21. The supply amount of the ink dissolving agent 11 of (1-100 / 150) × 100% = 33% can be saved at the second supply port 21.

  In addition, according to the present embodiment, the transfer object holding mechanism 50 includes a transfer object feeding unit 52 that feeds out the sheet-like transfer object 51, and a sheet-like transfer object that is fed out from the transfer object feeding part 52. The transfer object collecting unit 53 that collects the transfer object 51 and the transfer object 51 that is disposed opposite to the blanket cylinder 2 and is unwound from the transfer object feeding part 52 and collected by the transfer object collecting part 53 And a nipping roller 54 that presses toward the blanket cylinder 2. According to such a form, the sheet-like transferred object 51 can be slid by feeding the sheet-like transferred object 51 from the transferred object feeding part 52 and collecting it by the transferred object collecting part 53. . For this reason, even if ink and stain components are deposited on the sheet-like transfer object 51 and it becomes difficult to transfer further ink and stain components to the sheet-like transfer object 51, the sheet-like transfer object 51 is quickly transferred. Can be slid. As a result, a portion of the sheet-like transfer object 51 where ink and stain components are not deposited can be pressed toward the surface of the blanket cylinder 2, and the ink and stain components on the surface of the blanket cylinder 2 can be removed. It can be removed efficiently.

  Further, according to the present embodiment, the control unit 40 controls the supply amount of the ink dissolving agent 11 based also on the information related to the printing time T recorded in the recording unit 30. According to such a form, it is possible to calculate the amount of dirt components deposited in each region along the axial direction of the blanket cylinder 2 more accurately, and the supply ports 21 arranged in the axial direction of the blanket cylinder 2. The supply amount of the ink dissolving agent 11 to be supplied from can be determined with high accuracy. As a result, the loss of the ink dissolving agent 11 supplied to the surface of the blanket cylinder 2 can be further effectively reduced.

  Further, according to the present embodiment, as information regarding the axial distribution of the amount of ink supplied from the ink supply unit 4, the ink key opening degree of each ink key 7 arranged in the axial direction of the blanket cylinder 2 is the recording unit. 30. The ink key opening degree of each ink key 7 is a direct index indicating the amount of ink supplied from each ink key 7 and has a very strong correlation with the amount of ink supplied from each ink key 7. For this reason, the information regarding the axial distribution P of the amount of ink supplied from the ink supply unit 4 can be acquired with extremely high accuracy.

  Note that various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted.

  In the above-described embodiment, as shown in FIG. 3, the dissolving agent supply mechanism 20 dissolves ink supplied from the supply ports 21 to the surface of the blanket cylinder 2 by the valves 26 provided for the supply ports 21. Although the example in which the supply amount of the agent 11 is adjusted is shown, the configuration of the dissolving agent supply mechanism 20 is not limited to the configuration described above. FIG. 6 shows another example of the dissolving agent supply mechanism. In the example shown in FIG. 6, the dissolving agent supply mechanism 200 is connected between the dissolving agent storage unit 22 in which the ink dissolving agent 11 is stored and the supply port 21 corresponding to the dissolving agent storage unit 22 to store the dissolving agent. A pump 223 that pumps up ink from the section 22 and sends the ink dissolving agent 11 to the corresponding supply port 21.

  By adjusting the output of each pump 223 by the control unit 40, the supply amount of the ink dissolving agent 11 supplied from the corresponding supply port 21 to the surface of the blanket cylinder 2 can be adjusted. For this reason, the supply amount of the ink dissolving agent 11 supplied to the surface of the blanket cylinder 2 is adjusted along the axial direction of the blanket cylinder 2 by adjusting each pump 223 independently from the other pumps 223 by the control unit 40. It can be adjusted at each position corresponding to the supply port 21.

  According to such a modification, in order to adjust the supply amount of the ink dissolving agent 11 supplied from each supply port 21, it is necessary to regulate the pressure of the ink dissolving agent 11 between the pump 223 and the supply port 21. Therefore, the loss of the output of each pump 223 is small. For this reason, the ink dissolving agent 11 can be efficiently supplied to the surface of the blanket cylinder 2.

DESCRIPTION OF SYMBOLS 1 Offset printing machine 2 Blanket cylinder 3 Plate cylinder 4 Ink supply part 5 Ink fountain 6 Ink source roller 7 Ink key 8 Pressure cylinder 10 Blanket cylinder washing | cleaning apparatus 11 Ink solubilizer 20 Solvent supply mechanism 21 Supply port 22 Solvent storage part 23 Pump 24 Intermediate part 25 Solvent supply path 26 Valve 30 Recording part 31 Income means 32 Recording means 40 Control part 50 Transferred object holding mechanism 51 Transferred object 52 Transferred object feeding part 53 Transferred object recovery part 54 Nipping roller 91 Wetting Water supply unit 502 Blanket cylinder 511 Ink dissolving agent 520 Dissolving agent supply mechanism 550 Transfer object holding mechanism 551 Transfer object 554 Nipping roller

Claims (8)

A plate cylinder, an ink supply unit for supplying ink to the surface of the plate cylinder, the ink supply unit capable of adjusting the supply amount of the ink according to a position along the axial direction of the plate cylinder, and the plate A cleaning device for cleaning the blanket cylinder of an offset printing press, the blanket cylinder being disposed opposite to the cylinder and having a blanket cylinder on the surface of which ink supplied to the plate cylinder is transferred,
A plurality of supply ports arranged in the axial direction of the blanket cylinder, a dissolving agent supply mechanism for supplying an ink dissolving agent from each supply port to the surface of the blanket cylinder;
A recording unit that records at least one of information on the axial distribution of the pattern area ratio of the image printed by the offset printing machine and information on the axial distribution of the amount of ink supplied from the ink supply unit When,
Based on at least one of the information on the axial distribution of the pattern area ratio recorded on the recording unit and the information on the axial distribution of the amount of ink supplied from the ink supply unit, the dissolution agent supply mechanism A control unit for controlling the supply amount of the ink dissolving agent from each supply port;
A transferred object holding mechanism for pressing the transferred object to which the ink on the surface of the blanket cylinder dissolved by the ink dissolving agent is transferred, toward the blanket cylinder;
A blanket cylinder cleaning device. The transferred object holding mechanism is
A transferred object feeding portion for feeding the sheet-shaped transferred object;
A transfer object collecting unit for collecting the sheet-like transfer object fed from the transfer object feeding unit;
A nipping roller that is disposed to face the blanket cylinder and presses the transferred object before being transferred from the transferred object supply part and recovered by the transferred object recovery part toward the blanket cylinder;
The blanket cylinder cleaning apparatus according to claim 1, comprising: The pressing by the nipping roller is performed intermittently,
3. The blanket cylinder according to claim 2, wherein, when the transfer object is not pressed by the nipping roller, the transfer object is drawn out from the transfer object feeding part and collected in the transfer object collecting part. 4. Cleaning device. The recording unit also records information about the printing time that the offset printing machine was printing,
The blanket cylinder cleaning according to any one of claims 1 to 3, wherein the control unit controls a supply amount of the ink dissolving agent based on information on the printing time recorded in the recording unit. apparatus. The ink supply unit is
An ink fountain in which ink is stored;
An ink base roller supplied with ink from the ink fountain;
Have
The ink fountain includes a plurality of ink keys arranged in the axial direction of the ink base roller,
Each ink key can adjust the amount of ink supplied to the ink source roller by adjusting the ink key opening, which is the gap amount between the ink source roller, independently of the other ink keys. And
The blanket cylinder according to any one of claims 1 to 4, wherein an ink key opening degree of each ink key is recorded in the recording unit as information relating to an axial distribution of an ink supply amount supplied from the ink supply unit. Cleaning device. Plate cylinder,
An ink supply unit for supplying ink to the surface of the plate cylinder, the ink supply unit being capable of adjusting the supply amount of the ink according to the position along the axial direction of the plate cylinder;
A blanket cylinder that is arranged opposite to the plate cylinder and in which the ink supplied to the plate cylinder is transferred to the surface;
The blanket cylinder cleaning device according to any one of claims 1 to 5,
An offset printing machine. A plate cylinder, an ink supply unit for supplying ink to the surface of the plate cylinder, the ink supply unit capable of adjusting the supply amount of the ink according to a position along the axial direction of the plate cylinder, and the plate A cleaning method for cleaning the blanket cylinder of an offset printing press, the blanket cylinder being disposed opposite to the cylinder and having ink supplied to the plate cylinder transferred to the surface,
A step of recording at least one of information on the axial distribution of the pattern area ratio of the image printed by the offset printing machine and information on the axial distribution of the amount of ink supplied from the ink supply unit;
Based on at least one of the recorded information on the axial distribution of the pattern area ratio and the information on the axial distribution of the amount of ink supplied from the ink supply unit, the blanket cylinders are arranged in the axial direction. A step of supplying an ink dissolving agent controlled to a desired amount to the surface of the blanket cylinder from each supply port;
With
In the step of supplying the ink dissolving agent to the surface of the blanket cylinder, the object to be transferred is pressed toward the surface of the blanket cylinder supplied with the ink dissolving agent, and the ink dissolving agent is dissolved by the ink dissolving agent. A blanket cylinder cleaning method, wherein the ink on the surface of the blanket cylinder is transferred to the transfer object. The transferred object is in a sheet form, and is transferred from the transferred object supply part and is recovered by the transferred object recovery part,
In the step of supplying the ink dissolving agent to the surface of the blanket cylinder, the pressing by the nipping roller is performed intermittently,
8. The blanket cylinder according to claim 7, wherein when the transfer object is not pressed by the nipping roller, the transfer object is drawn out from the transfer object feeding part and collected in the transfer object collecting part. Cleaning method.

Images