Image forming apparatus and image forming system

Abstract

The image forming apparatus and the image forming system can reduce the setting space in the horizontal direction. The image forming apparatus (3) includes an image forming unit (7) that forms an image on a sheet (S), a drying unit (8) that dries the sheet (S), a cooling unit (9) that cools the sheet (S), and an inspection unit (10) that inspects the sheet (S). The drying unit (8), the cooling unit (9), and the inspection unit (10) are disposed below the image forming unit (7).

Description

Technical Field

[0001] The present invention relates to an image forming device and an image forming system. Background Art

[0002] Some image forming systems that form images on sheets include, in addition to an image forming section, a drying section that dries the sheets, a cooling section that cools the sheets, and the like.

[0003] For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2020-1282) discloses an image forming system in which a drying section (drying unit) and a cooling section (cooling / conveying unit) are arranged next to an image forming section (printing section).

[0004] In this way, in a configuration in which units such as a drying section and a cooling section are arranged next to an image forming section, there is a problem that the installation space in the horizontal direction increases.

[0005] Therefore, in the present invention, a subject is to reduce the installation space in the horizontal direction.

[0006] [Patent Document 1] (Japan) Patent Publication No. 2020-1282 Summary of the invention

[0007] In order to solve the above-mentioned problems, the image forming device involved in the present invention is characterized in that it includes: an image forming unit, which forms an image on a sheet; a drying unit, which dries the sheet; a cooling unit, which cools the sheet, and an inspection unit, which inspects the sheet, and the drying unit, the cooling unit and the inspection unit are arranged in the lower part of the image forming unit.

[0008] According to the present invention, the installation space in the horizontal direction can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 FIG. 1 is a schematic diagram showing the overall configuration of an image forming system according to an embodiment of the present invention.

[0010] Figure 2 FIG. 1 is a block diagram of a control unit of an image forming system according to an embodiment of the present invention.

[0011] Figure 3 FIG. 1 is a block diagram showing a more specific structure of a control unit according to an embodiment of the present invention.

[0012] Figure 4 FIG. 1 is a schematic diagram showing the overall operation flow of an image forming system according to an embodiment of the present invention.

[0013] Figure 5FIG. 1 is a diagram schematically showing the configuration of an image forming apparatus according to a first embodiment of the present invention.

[0014] Figure 6 FIG. 1 is a schematic diagram showing the structure of a drying unit according to a first embodiment of the present invention.

[0015] Figure 7 It is an explanatory diagram of the characteristic part of the drying section according to the first embodiment of the present invention.

[0016] Figure 8 FIG. 1 is a perspective view of an air blowing unit according to a first embodiment of the present invention.

[0017] Fig. 9 FIG. 1 is a diagram showing an exhaust flow path provided in a drying section according to a first embodiment of the present invention.

[0018] Fig.10 FIG. 1 is a diagram showing the direction of airflow occurring in the image forming apparatus according to the first embodiment of the present invention.

[0019] Fig.11 FIG. 1 is a schematic diagram showing the configuration of a cooling unit according to a first embodiment of the present invention.

[0020] Fig.12 (a) to (c) are illustrative diagrams of adjusting the contact distance of the sheet in the conveyance direction with respect to the cooling drum by changing the position of the guide roller in the first embodiment of the present invention.

[0021] Fig.13 FIG. 1 is a schematic diagram showing the structure of an inspection unit according to a first embodiment of the present invention.

[0022] Fig.14 FIG. 2 is a schematic diagram showing a structure of a drying unit according to a second embodiment of the present invention. DETAILED DESCRIPTION

[0023] First, based on Figure 1 , the overall structure of the image forming system 100 involved in the first embodiment of the present invention is described. In addition, in the various drawings used to describe the present invention, components or parts having the same function or shape are given the same reference numerals as long as they can be distinguished, and their repeated description is omitted after being described once.

[0024] <Configuration of Image Forming System>

[0025] like Figure 1As shown, the image forming system 100 includes a sheet feeding device 1, a pre-processing device 2, a first tension adjusting device 17, a first image forming device 3, a front and back reversing device 4, a second image forming device 5, a second tension adjusting device 18, and a sheet recovery device 6.

[0026] The sheet material feeding device 1 includes a feeding roller 11 for winding a long sheet material S into a roll. Figure 1 When rotating in the direction of the arrow shown, the sheets S are fed out from the supply roller 11 one after another.

[0027] The pre-treatment device 2 includes a treatment liquid coating unit 12 for coating a treatment liquid on one or both sides of the sheet S. The treatment liquid is, for example, a liquid having the function of agglomerating ink, and is coated on the sheet S for the purpose of improving image quality such as preventing ink penetration or assisting penetration.

[0028] The first tension adjusting device 17 is a device that transfers the sheet S from the preprocessing device 2 to the first image forming device 3 while adjusting the tension of the sheet S. The first tension adjusting device 17 includes a plurality of rollers around which the sheet S is stretched. The tension of the sheet S is adjusted by moving some of these rollers.

[0029] The first image forming apparatus 3 includes an image forming section 7 , a drying section 8 , a cooling section 9 , and an inspection section 10 .

[0030] The image forming unit 7 includes a plurality of inkjet liquid ejecting heads 13S, 13Y, 13M, 13C, and 13K as an example of a liquid ejecting unit. Figure 1 In the example of FIG. 1 , a liquid ejection head 13K for black ink, a liquid ejection head 13C for cyan ink, a liquid ejection head 13M for magenta ink, a liquid ejection head 13Y for yellow ink, and a liquid ejection head 13S for special color ink are sequentially arranged from the upstream side of the sheet conveying direction of the conveying sheet S. Special color ink is white or metallic ink other than black, cyan, magenta, and yellow, and is appropriately added according to the purpose. In addition, the arrangement of each liquid ejection head 13S, 13Y, 13M, 13C, and 13K is not limited to Figure 1 The order shown can be any order.

[0031] The drying section 8 includes a heating rotating body 20 for heating the sheet S. The heating rotating body 20 is configured to rotate as the sheet S is conveyed.

[0032] The cooling unit 9 includes a cooling rotor 30 for cooling the sheet S. The cooling rotor 30 is also configured to rotate as the sheet S is conveyed, similarly to the heating rotor 20 .

[0033] The inspection unit 10 includes a scanning camera 14 for acquiring position information of an image on the sheet S and a colorimeter 15 for acquiring color information of the image on the sheet S. The scanning camera 14 and the colorimeter 15 are examples of non-contact inspection devices for inspecting the image on the sheet S, and only one of them may be provided, or other inspection devices may be provided. Figure 1 In the example shown, the scanning camera 14 is arranged on the upstream side of the sheet conveying direction relative to the colorimeter 15, but the colorimeter 15 may be arranged on the upstream side of the sheet conveying direction relative to the scanning camera 14. The scanning camera 14 and the colorimeter 15 have detection sections arranged in the entire width direction of the sheet S so as to be able to inspect the entire width direction of the sheet S. In addition, the scanning camera 14 preferably has a resolution higher than the resolution of the image.

[0034] The front and back reversing device 4 is constituted by a well-known device that reverses the positions of the front side and the back side of the sheet S.

[0035] The second image forming apparatus 5 includes an image forming section 7, a drying section 8, a cooling section 9, and an inspection section 10, similarly to the first image forming apparatus 3. The configurations of the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 included in the second image forming apparatus 5 are basically the same as those of the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 included in the first image forming apparatus 3, and therefore description thereof will be omitted.

[0036] The second tension adjusting device 18 is a device that transfers the sheet S from the second image forming device 5 to the sheet collecting device 6 while adjusting the tension of the sheet S. The second tension adjusting device 18 is basically configured in the same manner as the first tension adjusting device 17. In addition, a housing is secured on the upper portion of each of the first tension adjusting device 17, the front and back reversing device 4, and the second tension adjusting device 18. Figure 1 The inner side of the inner part is recessed, and the space is large enough for the operator to enter. Therefore, the operator can stand on the first tension adjustment device 17, the front and back reversing device 4 or the second tension adjustment device 18 to operate the control panel or perform maintenance work.

[0037] The sheet recovery device 6 has a recovery roller 16 that winds up the sheet S for recovery. Figure 1 When rotating in the direction of the arrow shown, the sheet S is wound into a roll and collected.

[0038] <Control Unit Configuration>

[0039] Figure 2 FIG. 2 is a block diagram of the control unit 200 of the image forming system 100 according to an embodiment of the present invention.

[0040] like Figure 2As shown, the image forming system 100 includes a control unit 200 for controlling various operations of the sheet feeding device 1, the pre-processing device 2, the first tension adjusting device 17, the first image forming device 3, the front and back reversing device 4, the second image forming device 5, the second tension adjusting device 18, and the sheet collecting device 6. For example, the control unit 200 controls the rotation speed of the feeding roller 11, the ink ejection operation of each liquid ejecting head 13Y, 13M, 13C, and 13K, the heating temperature of the heating rotating body 20, the cooling temperature of the cooling rotating body 30, the rotation speed of the collecting roller 16, the tension applied to the sheet S, and the like. In addition, the control unit 200 can also correct the data of the image formed on the sheet S and the image forming conditions based on the position information of the image acquired by the scanning camera 14 of the inspection unit 10 and the color information of the image acquired by the colorimeter 15.

[0041] Figure 3 FIG. 2 is a block diagram showing a more specific structure of the control unit 200 according to one embodiment of the present invention.

[0042] like Figure 3 As shown, the control unit 200 includes a CPU (central processing unit) 60, a ROM (read only memory) 61, a RAM (random access memory) 62, an NVRAM (non-volatile random access memory) 63, an external device connection I / F 64, a network I / F 65, a bus 66, a main scanning driver 67, a sub-scanning driver 68, a liquid ejection driver 69, and an operation panel 70.

[0043] The CPU 60 controls the overall operation of the image forming system 100. The ROM 61 stores programs for driving the CPU 60 such as IPL. The RAM 62 is used as a work area for the CPU 60. The NVRAM 63 stores various data such as programs, and retains various data even when the power of the image forming system 100 is turned off.

[0044] The external device connection I / F 64 is connected to a PC (personal computer) via a USB (universal serial bus) cable or the like, and communicates control signals and print data with the PC. The network I / F 65 is an interface for data communication using a communication network such as the Internet. The bus 66 is an address bus and a data bus for electrically connecting various components such as the CPU 60.

[0045] The main scanning driver 67 controls movement in the main scanning direction of the carriage 130 carrying the liquid ejecting head 13. The "main scanning direction" referred to here is the width direction of the sheet, which means a direction perpendicular to the sheet conveying direction on a plane parallel to the sheet.

[0046] The sub-scanning driver 68 controls the conveyance of the sheet S by the sheet conveying unit 140. The sheet conveying unit 140 includes, for example, a roller and a motor driving the roller, and intermittently conveys the sheet S in the sub-scanning direction, which is the sheet conveying direction. While the sheet S is intermittently conveyed in the sub-scanning direction by the control of the sub-scanning driver 68, the carriage 130 is moved in the main scanning direction by the control of the main scanning driver 67 and ink is ejected from the liquid ejecting head 13, thereby forming an image on the sheet S.

[0047] The liquid ejection operation of the liquid ejection head 13 is controlled by a liquid ejection driver 69. In this example, the liquid ejection driver 69 is mounted on the carriage 130, but the liquid ejection driver 69 may be connected to the bus 66 outside the carriage 130. In addition, the main scanning driver 67, the sub-scanning driver 68, and the liquid discharge driver 69 may be functions realized by commands of the CPU 60 according to the program.

[0048] The operation panel 70 displays current setting values ​​and selection screens, and is composed of a touch panel and an alarm lamp for receiving input from an operator.

[0049] <Overall Operation of Image Forming System>

[0050] Figure 4 FIG. 1 is a schematic diagram showing the overall operation flow of the image forming system 100 according to one embodiment of the present invention.

[0051] When the operation of the image forming system 100 starts, the supply roller 11 of the sheet supply device 1 rotates, thereby executing a “sheet supply process” in which the sheet S is supplied from the supply roller 11.

[0052] Then, the sheet S is conveyed to the pre-treatment device 2, and a “pre-treatment process” is performed in which the treatment liquid is applied to the sheet S by the treatment liquid application unit 12 of the pre-treatment device 2.

[0053] Next, the sheet S is conveyed to the first image forming device 3 via the first tension adjusting device 17. Then, in the first image forming device 3, each process A of forming an image on the sheet S, the "image forming process" of drying the sheet S, the "cooling process" of cooling the sheet S, and the "inspection process" of inspecting the sheet S are sequentially performed. First, in the "image forming process", by conveying the sheet S to the image forming unit 7 in the first image forming device 3, ink is ejected from each ejection head 1313Y, 13M, 13C, 13K onto the first surface (surface side) of the sheet S, and an image is formed on the first surface.

[0054] Next, the sheet S is conveyed to the drying section 8 in the first image forming apparatus 3 and is subjected to a "drying process" in the drying section 8. In the drying section 8, the conveyed sheet S is heated by contacting with the surface of the heating rotating body 20. As a result, the liquid component of the ink on the sheet S evaporates, and the sheet S is dried.

[0055] Next, the sheet S is conveyed to the cooling section 9 in the first image forming apparatus 3 and is subjected to a “cooling process” in the cooling section 9. In the cooling section 9, the conveyed sheet S contacts the surface of the cooling rotating body 30, so that the sheet S is cooled.

[0056] Furthermore, the sheet S is conveyed to the inspection unit 10 in the first image forming device 3 and undergoes an "inspection process" of the inspection unit 10. In the "inspection process", the position information of the image on the sheet S is acquired by the scanning camera 14, and the color information of the image on the sheet S is acquired by the colorimeter 15.

[0057] Then, the sheet S is conveyed to the front and back reversing device 4, and a “front and back reversing process” is performed in which the front and back of the sheet S are reversed by the front and back reversing device 4.

[0058] The sheet S after the front and back sides are turned over is conveyed to the second image forming device 5. That is, in the second image forming device 5, the second side (the back side) of the sheet S, which is the opposite side to the first side, is conveyed in a manner facing each of the ejection heads 13, 13Y, 13M, 13C, and 13K. Therefore, when the sheet S is conveyed to the second image forming device 5, ink is ejected onto the second surface of the sheet S, thereby forming an image on the second surface. In addition, in the second image forming device 5, as in the first image forming device 3, in addition to the "image forming process", each process B of the "drying process", "cooling process", and "inspection process" is also performed. The basic operations of the "image forming process", "drying process", "cooling process", and "inspection process" in the second image forming device 5 are the same as the basic operations of each process A in the first image forming device 3, so the description is omitted.

[0059] Then, the sheet S is conveyed to the sheet recovery device 6 via the second tension adjustment device 18, and the “sheet recovery process” is performed. In the “sheet recovery process”, the sheet S is wound and recovered by the recovery roller 16. Thus, a series of operations of the image forming system 100 are completed.

[0060] As described above, in the image forming system 100 according to the first embodiment of the present invention, since the "inspection process" of acquiring the position information and color information of the image is performed by the first image forming device 3 and the second image forming device 5, it is possible to automatically detect a defective image. For example, based on the position information of the image acquired by the scanning camera 14, in addition to the positional deviation between the target image and the actual image on each of the first and second sides of the sheet S, the relative positional deviation of each image on the first side and the second side, the deviation of the image size, etc. can be detected. In addition, based on the color information of the image acquired by the colorimeter 15, color unevenness, color loss, etc. of each image on the first side and the second side can also be detected.

[0061] In addition, the results obtained through each "inspection process" can also be fed back to the "image forming process" of the first image forming device 3 and the second image forming device 5 by the control unit 200, and the image formation is performed based on the corrected image data or image forming conditions. In this way, the occurrence of positional deviation and color unevenness of the image can be suppressed. In addition, the control unit 200 can also perform feedforward control on the "image forming process" of the second image forming device 5 based on the results obtained through the "inspection process" of the first image forming device 3. In this case, the positional deviation of each image on the first side and the second side can be suppressed, and the image quality can be improved. Further, the feedback control and feedforward control based on the inspection results can be selected and executed according to the image forming conditions or the image forming mode. In addition, in the case of a bad image, the location of the bad image can be marked on the sheet S, or the information of the bad image can be recorded, so that the operator can confirm the bad location or bad state after the sheet is recovered. In this way, in the first embodiment of the present invention, the image forming system 100 is provided with an inspection unit 10 that automatically inspects the image, thereby improving the image quality and reducing the monitoring burden or inspection burden of the operator.

[0062] <Issues in image forming systems>

[0063] However, in an image forming system having a plurality of devices such as a sheet material feeding device, a pre-processing device, and an image forming device, if the devices are arranged horizontally, the installation space in the horizontal direction will increase, and the installation of the image forming system will be restricted. In particular, in the field of commercial printing, the installation space problem becomes significant because large devices are used.

[0064] In addition, in the previous configuration, some will adopt a method of adding an inspection device as an optional unit as needed. In this case, since the inspection device is generally arranged side by side with the peripheral device, the addition of the inspection device will cause the problem of increasing the installation space of the entire image forming system. In addition, in the case where the inspection device is separate from other devices, when the inspection device is added, the position of the inspection device relative to the peripheral device will deviate, and it may not be possible to inspect the image on the sheet with high precision. In addition, the inspection of the image is preferably carried out in a stable state immediately after the sheet is dried and cooled, but in the case where the inspection device is separate, the conveying distance of the sheet from the drying device and the cooling device to the inspection device becomes longer, so there is also a problem of difficulty in inspecting the image immediately after drying and cooling.

[0065] Therefore, in the present invention, first, the horizontal installation space in the image forming system is reduced, and second, the inspection accuracy is improved. Hereinafter, the characteristic part of the present invention will be described by taking the structure involved in the first embodiment of the present invention as an example.

[0066] <Configuration of Characteristic Portions According to the First Embodiment of the Present Invention>

[0067] Figure 5 FIG. 1 is a diagram schematically showing the structure of an image forming apparatus 3 according to a first embodiment of the present invention.

[0068] First, refer to Figure 5 , the layout of the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 is described. Here, the configuration of the first image forming device 3 is described as an example, and the configuration of the second image forming device 5 is the same as that of the first image forming device 3, so the description is omitted.

[0069] like Figure 5 As shown, in the first image forming device 3, the drying section 8, the cooling section 9, and the inspection section 10 are arranged below the image forming section 7. The "below" of the image forming section 7 mentioned here means that the drying section 8, the cooling section 9, and the inspection section 10 are arranged below the image forming section 7, and when viewed from above in the vertical direction, at least a portion of each of the drying section 8, the cooling section 9, and the inspection section 10 overlaps with the image forming section 7. Therefore, when viewed from above in the vertical direction, in addition to the case where the drying section 8, the cooling section 9, and the inspection section 10 are arranged so as to overlap with the image forming section 7 as a whole, it is also possible to arrange so as to overlap with the image forming section 7 only a portion of each.

[0070] In the first embodiment of the present invention, most of the drying section 8, the entire cooling section 9, and the entire inspection section 10 are arranged at the lower part of the image forming section 7. In addition, when the direction in which the sheet S is conveyed in the image forming section 7 is taken as the first direction Y1, and the direction opposite to the first direction Y1 is taken as the second direction Y2, the drying section 8, the cooling section 9, and the inspection section 10 are arranged in the order of the drying section 8, the cooling section 9, and the inspection section 10 toward the second direction Y2. Therefore, in the first embodiment of the present invention, the outlet C of the drying section 8 and the inlet D of the inspection section 10 are arranged at the lower part of the image forming section 7. In this case, the "outlet C of the drying section 8" is, for example, a portion where the sheet S is discharged from the frame of the drying section 8, and also includes a transfer portion or a connection portion where the sheet S is transferred from the drying section 8 to the cooling section 9. In addition, the "inlet D of the inspection section 10" is, for example, a portion where the sheet S enters the inspection range (detection range) of the scanning camera 14, and includes a transfer portion or a connection portion where the sheet S is transferred from the cooling section 9 to the inspection section 10. In addition, the inlet J of the image forming device is arranged below the outlet C of the drying section 8 and the cooling section 9 as a whole. The "inlet J of the image forming device" mentioned here refers to the connection part or the transmission part between the image forming device and the nearest device located on the upstream side of the sheet conveying direction. For example, in the case of the first image forming device 3, the connection part or the transmission part between the first image forming device 3 and the first tension adjustment device 17 is equivalent to the inlet of the first image forming device 3, and in the case of the second image forming device 5, the connection part or the transmission part between the second image forming device 5 and the front and back reversing device 4 is equivalent to the inlet of the second image forming device 5. In addition, "below the outlet C of the drying section 8 and the cooling section 9 as a whole" refers to a position lower than the outlet C of the drying section 8 and the cooling section 9 as a whole in the vertical direction.

[0071] Thus, in the first embodiment of the present invention, since the drying section 8, the cooling section 9, and the inspection section 10 are arranged below the image forming section 7, the installation space in the horizontal direction can be reduced compared to the case where they are arranged horizontally with respect to the image forming section 7. Therefore, according to the first embodiment of the present invention, it is not easy to be restricted by the installation area, and it is easy to install the image forming system and to add other devices as needed.

[0072] In the first embodiment of the present invention, the drying section 8, the cooling section 9, and the inspection section 10 are arranged in the order of the drying section 8, the cooling section 9, and the inspection section 10 facing the second direction Y2, so that a conveying path is formed in which the sheet S is efficiently conveyed from the image forming section 7 to the drying section 8, the cooling section 9, and the inspection section 10 in sequence. That is, since the sheet S is conveyed in the first direction Y1 in the image forming section 7 and then conveyed in a manner of turning back in the second direction Y2 from the drying section 8 to the cooling section 9 and the inspection section 10, the conveying path of the sheet S does not become unnecessary long, and the sheet S can be efficiently conveyed. In addition, the inspected sheet S passes through the lower part of the inspection section 10, the lower part of the cooling section 9, and the lower part of the drying section 8 in sequence in the first direction Y1 and is output. In this way, in the first embodiment of the present invention, since the layout of the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 is determined in such a manner that the sheet S can be efficiently conveyed in the first image forming device 3, the device can be miniaturized. Furthermore, since the conveying distance of the sheet S conveyed from the drying pass 8 and the cooling pass 9 to the inspection pass 10 can be shortened, inspection of an image can be performed in a stable state immediately after the sheet S is dried and cooled, thereby improving inspection accuracy.

[0073] In addition, depending on the layout of the peripheral devices including the image forming unit 7, the drying unit 8, the cooling unit 9, and the inspection unit 10 may be arranged in the order of the drying unit 8, the cooling unit 9, and the inspection unit 10 toward the first direction Y1, which is opposite to the first embodiment of the present invention. The arrangement of the drying unit 8, the cooling unit 9, and the inspection unit 10 can be changed appropriately.

[0074] In addition, in the first embodiment of the present invention, the drying section 8, the cooling section 9, and the inspection section 10 are arranged at the lower part of the image forming section 7, and further, the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 are arranged in the same frame 19 provided by the first image forming device 3. Thus, compared with the configuration in which the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 each have a frame separately, and each frame is arranged in a manner in which the outer surface is opposite, the device can be miniaturized. That is, by arranging the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 in the same frame 19, it is easy to arrange each device and each component close to each other, so that the device and the components can be efficiently arranged to achieve miniaturization. In addition, the "same frame" is not limited to the case where it is composed of one outer packaging component, but can also be composed of multiple outer packaging components. In addition, each component arranged in the same frame may not be held by the same (one) side plate. That is, the present invention also includes a configuration in which each component is held by multiple side plates.

[0075] In addition, in the first embodiment of the present invention, the inspection unit 10 is not a separate unit separated from the image forming unit 7, the drying unit 8, and the cooling unit 9 as a frame, but is configured as an integrated unit provided in the same frame 19, so that the inspection accuracy of the inspection unit 10 is improved. That is, by providing the inspection unit 10 with the image forming unit 7, the drying unit 8, and the cooling unit 9 as a whole, the relative position of the inspection unit 10 relative to the image forming unit 7, the drying unit 8, and the cooling unit 9 is fixed, so that the position of the inspection unit 10 can be prevented from being offset, and the image on the sheet S can be inspected with high accuracy. In addition, since the conveying distance of the sheet S conveyed from the drying transfer 8 and the cooling transfer 9 to the inspection transfer 10 can be shortened, the image inspection can be performed in a stable state immediately after the sheet S is dried and cooled, thereby improving the inspection accuracy. As a result, the reliability of the image inspection is improved.

[0076] As described above, in the first embodiment of the present invention, the installation space in the horizontal direction can be reduced, and the inspection accuracy can be improved. On the other hand, since the drying section 8, the cooling section 9, and the inspection section 10 are arranged below the image forming section 7, the first image forming device 3 may be enlarged in the vertical direction. Since the enlargement in the vertical direction may deteriorate the operability during the storage and transportation of the image forming device, and may also deteriorate the assembly and maintenance properties, it is preferable to suppress the enlargement in the vertical direction.

[0077] Therefore, in the first embodiment of the present invention, in order to suppress the up-down enlargement of the image forming apparatus, the following operation is performed. Hereinafter, each structure of the drying section 8, the cooling section 9, and the inspection section 10 of the first embodiment of the present invention will be described in detail, including the countermeasures for suppressing the up-down enlargement.

[0078] <Construction of Drying Section>

[0079] Figure 6 FIG. 2 is a diagram schematically showing the structure of a drying unit 8 according to the first embodiment of the present invention.

[0080] like Figure 6 As shown, the drying section 8 includes a heating roller 21 , a heating drum 22 , a guide roller 23 , and an air blowing unit 24 .

[0081] The heating roller 21 and the heating drum 22 are heating rotating bodies 20 having heating sources 250, 260 such as halogen heaters inside. The heating drum 22 is a heating rotating body 20 having a larger diameter than the heating roller 21, and one is arranged near the center of the drying section 8. In addition, a plurality of heating rollers 21 are arranged in a spiral shape around the heating drum 22.

[0082] Unlike the heating roller 21 and the heating drum 22 , the guide roller 23 is a rotating body that does not have a heating source inside and serves as a guide member for guiding the sheet S. In this case, like the heating roller 21 , a plurality of guide rollers 23 are also arranged in a spiral shape around the heating drum 22 .

[0083] The air blowing unit 24 is an air blowing mechanism that blows air toward the sheet S to promote drying of the sheet S. The plurality of air blowing units 24 are arranged to face the sheet S stretched and stretched by the heating roller 21 , the heating drum 22 , and the guide roller 23 .

[0084] When the sheet S is input into the drying section 8, first, the sheet S is set on the outside of the plurality of heating rollers 21. In addition, the "outside" of the heating roller 21 mentioned here refers to the side opposite to the side facing the heating roller 22 in the outer peripheral surface of the heating roller 21. Then, the sheet S is conveyed while contacting the outside of the heating roller 21, and then is rolled onto the heating roller 22. Then, the sheet S is set from the heating roller 22 to the guide roller 23, and is conveyed while contacting the inside of the plurality of heating rollers 21 (the side facing the heating roller 22). Thus, the surface of the sheet S on the opposite side to the image forming surface is conveyed in contact with the outside of the heating roller 21, the heating roller 22, and the inside of the heating roller 21 in sequence, and is heated from the surface on the opposite side to the image forming surface. Further, air is blown to the image forming surface of the sheet S through the plurality of air blowing units 24. Thus, the sheet S is dried. Then, the sheet S is guided by the guide roller 23 and output from the drying section 8.

[0085] Here, if Figure 7 As shown, in the first embodiment of the present invention, the plurality of heating rollers 21 are arranged in an elliptical track E. In this way, by arranging the plurality of heating rollers 21 in the elliptical track E, the size (height) of the drying section 8 in the vertical direction can be reduced. That is, by arranging the plurality of heating rollers 21 in the elliptical track E, the maximum size H in the vertical direction of the region where the heating rollers 21 are arranged can be made smaller than the maximum size W in the horizontal direction when viewed from the axial direction of each heating roller 21, so that the drying section 8 can be miniaturized in the vertical direction. As a result, the first image forming device 3 including the drying section 8 can be miniaturized in the vertical direction as a whole.

[0086] In the first embodiment of the present invention, the sheet S is heated by the plurality of heating rollers 21 in a spiral shape ( Figure 7 After being guided in the counterclockwise direction in the middle of the sheet S, the direction of the sheet S is changed starting from the heating roller 22 and is guided in a spiral shape ( Figure 7Thus, by changing the direction of the sheet S in the drying section 8 and then conveying it, the sheet S can be efficiently heated even in a small space, and high drying performance can be obtained.

[0087] Furthermore, in order to realize such a compact conveying path of the sheet S, in the first embodiment of the present invention, the direction-changing portion F of the sheet S may be configured as follows.

[0088] Here, in the heating rotating body 20 including the heating roller 21 and the heating drum 22, there are a first heating rotating body with which the sheet S contacts twice from different directions and a second heating rotating body with which the sheet S contacts only once. In this case, the first heating rotating body is the heating roller 21A ( Figure 7 The second heating rotating body is the heating roller 21B ( Figure 7 After being conveyed while contacting the plurality of heating rollers 21A (with hatching) as the first heating rotating body, the sheet S changes its direction by passing through three heating rollers 21B (without hatching) and one heating roller 22 as the second heating rotating body, and is conveyed again while contacting the respective heating rollers 21A (with hatching) as the first heating rotating body.

[0089] Thus, in the first embodiment of the present invention, the direction-changing section F is formed by three heating rollers 21B (without hatching) as the second heating rotating body and one heating drum 22, so that one surface of the sheet S is brought into contact with each heating roller 21A (with hatching) as the first heating rotating body again. Thus, a compact sheet conveying path is realized while ensuring high drying performance, and the device is miniaturized.

[0090] Figure 8 FIG. 1 is a perspective view of an air blowing unit 24 according to a first embodiment of the present invention.

[0091] like Figure 8 As shown, the air blowing unit 24 has a blow hole 25 and an air intake hole 26 on a surface 240 disposed opposite to the sheet. In addition, the air blowing unit 24 has an air supply duct 27 and an air intake duct 28 inside. The air supply duct 27 is connected to the blow hole 25, and the air intake duct 28 is connected to the air intake hole 26.

[0092] Fig. 9 FIG. 1 is a diagram showing an exhaust flow path 40 provided in a drying unit 8 according to the first embodiment of the present invention.

[0093] like Fig. 9As shown, a supply and exhaust flow path 40 is provided in the drying section 8 to inhale air from the right side of the figure, i.e., the front side, and the left side of the figure, i.e., the back side, to supply air to the interior, and exhaust air from the back side. Specifically, the supply and exhaust flow path 40 includes air supply holes 41A and 41B provided on the front side and the back side; air supply ducts 42A and 42B connected to the air supply holes 41A and 41B; an exhaust hole 43 provided on the back side; and exhaust ducts 44A, 44B, and 44C connected to the exhaust hole 43.

[0094] The air supply ducts 42A and 42B extend radially from the air supply holes 41A and 41B on the front and rear sides and are connected to both ends of the air supply duct 27 of each air blowing unit 24. Thus, an air supply path is formed for passing air from each air supply hole 41A and 41B to each air blowing unit 24 via the air supply ducts 42A and 42B.

[0095] The exhaust ducts 44A, 44B, and 44C include the front exhaust duct 44A extending radially on the front side, the back exhaust duct 44B extending radially on the back side, and the central exhaust duct 44C passing through the center of the drying section 8. The front and back exhaust ducts 44A and 44B are connected to both ends of the air supply duct 27 of each air blowing unit 24. In addition, the front and back exhaust ducts 44A and 44B are connected to the exhaust hole 43 via the central exhaust duct 44C. Thus, an exhaust path is formed for allowing air to flow from each air blowing unit 24 to the exhaust hole 43 via the exhaust ducts 44A, 44B, and 44C.

[0096] like Fig. 9 As shown by the arrows in FIG. 1 , when air is sucked from the air supply holes 41A and 41B on the front and back sides, the air is transported to the air supply ducts 27 of the blowing units 24 through the air supply ducts 42A and 42B on the front and back sides. Then, the air is blown out from the air supply holes 25 and blown toward the sheet material. Thus, the drying of the sheet material is promoted.

[0097] In addition, air containing water vapor and the like generated from the sheet material accompanying drying is sucked in from the air intake holes 26 of each blowing unit 24. Then, the air sucked in from the air intake holes 26 is collected in the central exhaust duct 44C through the air intake duct 28 of each blowing unit 24 and the exhaust ducts 44A and 44B on the front side and the back side, and is exhausted from the exhaust holes 43. Thus, since the air containing water vapor and the like is exhausted from the drying section 8 to the outside, the humidity environment in the drying section 8 can be appropriately maintained.

[0098] Thus, in the first embodiment of the present invention, since the air supply and exhaust flow path 40 for supplying air into the drying section 8 and exhausting air from the drying section 8 is provided, the air supply and exhaust of the drying section 8 are controlled. Fig.10As shown by the arrow in , an airflow is generated from the cooling section 9 and the inspection section 10 toward the drying section 8. In the cooling section 9 and the inspection section 10, although not as good as in the drying section 8, water vapor and the like are sometimes generated from the sheet S. Therefore, by generating an airflow from the cooling section 9 and the inspection section 10 toward the drying section 8, the water vapor and the like can be moved toward the drying section 8. Thus, the humidity environment can be appropriately maintained in the cooling section 9 and the inspection section 10. In addition, since dust and the like floating around the inspection section 10 can also be moved to the drying section 8 side by the airflow, it is possible to suppress the attachment of dust and the like to the detection section of the scanning camera 14 and the colorimeter 15, and it is possible to maintain good inspection accuracy.

[0099] <Cooling Section Configuration>

[0100] Fig.11 1 is a schematic diagram showing the configuration of a cooling unit 9 according to the first embodiment of the present invention.

[0101] like Fig.11 As shown, the cooling section 9 includes a cooling drum 31 and guide rollers 32 .

[0102] The cooling drum 31 is an example of the cooling rotating body 30. The cooling drum 31 is composed of a rotating body having a larger diameter than the guide roller 32, and has a refrigerant flow path inside for a refrigerant such as cooling water to pass through. In this case, two cooling drums 31 are arranged side by side in the vertical direction. In addition, the number and arrangement of the cooling drums 31 are not limited to Fig.11 Example shown.

[0103] The guide roller 32 is an example of a guide member for guiding the sheet S. In this case, a plurality of guide rollers 32 are arranged around the cooling drum 31, but one guide roller may be used. The sheet S is guided by the guide roller 32 and is wound around the outer peripheral surface of each cooling drum 31, thereby cooling the sheet S.

[0104] However, the ease with which the sheet S is cooled varies depending on its thickness or type. For example, thicker paper than ordinary paper is more difficult to cool than ordinary paper, so the time required for cooling tends to be longer. Therefore, in the first embodiment of the present invention, the position of the guide roller 32 can be changed, and the contact distance (winding length) of the sheet S relative to the conveying direction of the cooling drum 31 can be adjusted.

[0105] For example, by changing the position of the guide roller 32B from Fig.12 The state shown in (a) changes to Fig.12 (b) shows the state, the contact distance L between the sheet S and the upper cooling roller 31 in the conveying direction can be shortened. Fig.12 (a) is changed to Fig.12In the position (c), the contact distance L between the sheet S and both the upper and lower cooling drums 31 in the conveying direction can be shortened.

[0106] Thus, in the first embodiment of the present invention, by changing the position of the guide roller 32, the contact distance L of the sheet S in the conveying direction relative to the cooling drum 31 can be adjusted. Thus, in the case of a sheet S that is difficult to cool, the contact distance L of the sheet S in the conveying direction relative to the cooling drum 31 is extended to ensure a long cooling time. Conversely, in the case of a sheet S that is easy to cool, the contact distance L of the sheet S in the conveying direction relative to the cooling drum 31 is shortened to shorten the cooling time, thereby enabling cooling corresponding to the thickness or type of the sheet S. Furthermore, since the contact distance L in the conveying direction of the sheet S can be adjusted with less space, miniaturization of the device can also be achieved. In addition, in the first embodiment of the present invention, the cooling unit 9 is arranged in the frame 19 of the first image forming device 3 (refer to Fig.10 ) and does not have a separate frame, thereby increasing the degree of freedom in changing the position of the guide roller 32. That is, the position of the guide roller 32 can be greatly changed without being restricted by the size of the separate frame. Thus, the cooling capacity is optimized.

[0107] Furthermore, the position change of the guide roller 32 is not limited to the case where it is performed based on either one of the information of the type and thickness of the sheet S, but can be performed based on both information. In addition, the position change of the guide roller 32 can be performed manually by an operator or the like, or can be performed automatically using a well-known moving mechanism including an eccentric cam and a spring. In addition, in addition to the case where the position of the guide roller 32 is changed, the contact distance L of the sheet S in the conveying direction of the cooling drum 31 can also be adjusted by changing the number of guide rollers 32.

[0108] <Composition of the Inspection Department>

[0109] Fig.13 FIG. 1 is a diagram schematically showing the configuration of an inspection unit 10 according to a first embodiment of the present invention.

[0110] like Fig.13 As shown, the inspection unit 10 includes a plurality of guide rollers 50 in addition to the scanning camera 14 and the colorimeter 15 .

[0111] The guide roller 50 is an example of a guide member for guiding the sheet S, and one is arranged above the scanning camera 14 and one is arranged below the colorimeter 15. Therefore, the sheet S is guided from the upper guide roller 50 to the lower guide roller 50 so as to pass in front of the scanning camera 14 and the colorimeter 15. At this time, in order to check the image on the sheet S guided downward, the scanning camera 14 and the colorimeter 15 are arranged so that the respective detection surfaces 14a and 15a facing the image forming surface of the sheet S are oriented in a substantially horizontal direction.

[0112] Thus, in the first embodiment of the present invention, since the respective detection surfaces 14a, 15a of the scanning camera 14 and the colorimeter 15 are arranged to face the substantially horizontal direction, it is difficult for water vapor and dust to adhere to each detection surface 14a, 15a. Thus, it is possible to avoid the change of detection accuracy or the reduction of detection accuracy caused by the attachment of water vapor to each detection surface 14a, 15a, thereby improving the inspection accuracy. In addition, in the first embodiment of the present invention, since the scanning camera 14 and the colorimeter 15 are arranged at a position that does not overlap with the range above the vertical direction of each cooling drum 31, it is also possible to prevent the attachment of water vapor and the like generated in the cooling unit 9 to each detection surface 14a, 15a.

[0113] <Configuration of the Second Embodiment of the Present Invention>

[0114] Fig.14 FIG. 2 is a schematic diagram showing the structure of a drying unit 8 according to a second embodiment of the present invention.

[0115] The image forming apparatus according to the present invention includes a drying section including Figure 6 and Figure 7 In addition to the drying section 8 shown in the figure, it can also be Fig.14 The drying section 8 is shown. Fig.14 The drying section 8 shown has two heating drums 22 , a plurality of heating rollers 21 and a plurality of guide rollers 23 .

[0116] In this case, the heating rollers 21 and the guide rollers 50 are arranged around the heating drum 22 not in a spiral shape but along an elliptical trajectory E. In this way, when each heating roller 21 is arranged along the elliptical trajectory E, the maximum dimension H in the vertical direction of the region where each heating roller 21 is arranged can be made smaller than the maximum dimension W in the horizontal direction, so that the drying section 8 can be miniaturized in the vertical direction.

[0117] In addition, Fig.14In the example shown, when the sheet S is input into the drying section 8, after being conveyed while contacting a plurality of heating rollers 21A (with hatching lines) serving as a first heating rotating body, the sheet S changes its direction through a heating roller 21B (without hatching lines) serving as a second heating rotating body and two heating rollers 22, and is conveyed again while contacting each of the heating rollers 21A (with hatching lines) serving as a first heating rotating body while being guided by a plurality of guide rollers 23.

[0118] At this time, a heating roller 21B (without cross-section lines) that contacts the sheet S only once and two heating rollers 22 are used as the second heating rotating body to change the direction of the sheet S so that one side of the sheet S contacts the heating rollers 21A (with cross-section lines) that serve as the first heating rotating body again.

[0119] That is, in this case, the three second heating rotating bodies of the one heating roller 21B and the two heating drums 22 constitute the direction-changing section F for changing the direction of the sheet S. In this way, by constituting the direction-changing section F with the three second heating rotating bodies, it is possible to ensure high drying performance and realize a compact sheet conveying path. In addition, the number of the second heating rotating bodies arranged on the path for guiding the sheet having one side in contact with and passing through the first heating rotating body so that the same side contacts the first heating rotating body again, i.e., the number of the second heating rotating bodies constituting the direction-changing section F, may be other than three. Figure 7 Although the number is four as in the example shown, the number may be five or more.

[0120] The above describes the various embodiments of the image forming system and the image forming device of the present invention, but the image forming system and the image forming device of the present invention are not limited to the above embodiments. The image forming system and the image forming device of the present invention are not limited to devices that visualize meaningful images such as characters and graphics by ejecting liquid, but may also be devices that form patterns that are meaningless in themselves. In addition, the images mentioned in the present invention are not limited to characters, lines, photos, etc., but also include circuit patterns or symbol diagrams formed on printed circuit boards.

[0121] In addition, the image forming system of the present invention may also be provided with a post-processing device for cutting the sheet after the image is formed, in addition to forming an image on a long continuous sheet and then winding the sheet for recycling. In addition, the image forming system of the present invention may also form an image on a sheet that has been cut into a predetermined size in advance.

[0122] In addition, the liquid ejection unit of the image forming apparatus according to the present invention may be a liquid ejection unit that ejects liquid while moving, or a liquid ejection unit that ejects liquid without moving. As specific examples, there are a serial type liquid ejection head that ejects liquid while moving in the width direction of a stationary sheet, and a line type liquid ejection head that ejects liquid in a stationary state with respect to a moving sheet.

[0123] In addition, the "liquid" ejected from the liquid ejection portion is not particularly limited as long as it has a viscosity and surface tension that can be ejected, but preferably a liquid having a viscosity of 30 MPa·s or less at normal temperature and pressure or when heated or cooled. Specifically, it includes solvents such as water or organic solvents, colorants such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, biocompatible materials such as DNA, amino acids, proteins, and calcium, and edible materials such as natural pigments, solutions, suspensions, and latexes.

[0124] In addition, the sheet material used in the present invention refers to a substance to which liquid can at least temporarily adhere, including substances that stick after attachment and penetrate after attachment. As specific examples, there are recorded media such as paper, recording paper, recording paper, film materials, cloth, and electronic substrates. As materials of the sheet material, paper, silk, fiber, cloth, leather, metal, plastic, glass, wood, ceramics, etc. can be listed. In addition, the sheet material can be a method of uninterrupted continuous conveyance from the sheet material supply device to the sheet material recovery device, or a method of discontinuously conveying one by one independently from the sheet material supply device to the sheet material recovery device.

[0125] Summarizing the above-described aspects of the present invention, the present invention includes at least the following aspects.

[0126] [First method]

[0127] The first mode is an image forming device, characterized in that it includes: an image forming unit, which forms an image on a sheet; a drying unit, which dries the sheet; a cooling unit, which cools the sheet, and an inspection unit, which inspects the sheet, wherein the drying unit, the cooling unit and the inspection unit are arranged at the bottom of the image forming unit.

[0128] [Second method]

[0129] The second mode is an image forming apparatus according to claim 1 in the first mode, characterized in that the drying section, the cooling section, and the inspection section are arranged in a manner such that at least a portion of each overlaps a portion of the image forming section when viewed from above in a vertical direction.

[0130] [Third Method]

[0131] A third aspect is that in the first or second aspect, the image forming section, the drying section, the cooling section, and the inspection section are provided in the same housing.

[0132] [Fourth Method]

[0133] A fourth aspect is any one of the first to third aspects, wherein the outlet of the drying section, the entire cooling section, and the inlet of the inspection section are arranged below the image forming section.

[0134] [Fifth Method]

[0135] A fifth aspect is any one of the first to fourth aspects, wherein the inlet of the image forming device is arranged below the outlet of the drying section and the entire cooling section.

[0136] [Sixth Method]

[0137] The sixth mode is that in the image forming unit of any one of the first to fifth modes, when the direction of conveying the sheet in the image forming unit is set to a first direction and the direction opposite to the first direction is set to a second direction, the drying unit, the cooling unit and the inspection unit are arranged in the order of the drying unit, the cooling unit and the inspection unit facing the second direction.

[0138] [Seventh method]

[0139] The seventh method is that in any one of the first to sixth methods, the drying section has a plurality of first heating rotating bodies with which the sheet contacts twice from different directions, and a second heating rotating body with which the sheet contacts once, and at least three of the second heating rotating bodies are arranged on a path that guides the sheet, which contacts and passes through one side of the sheet, in such a manner that the one side of the sheet contacts the first heating rotating body.

[0140] [Eighth Method]

[0141] An eighth aspect is any one of the first to seventh aspects, wherein an airflow is generated from the inspection section and the cooling section toward the drying section.

[0142] [Ninth method]

[0143] A ninth aspect is any one of the first to eighth aspects, wherein the cooling unit includes a cooling rotating body that cools the sheet and a guide member that guides the sheet.

[0144] [Tenth Method]

[0145] A tenth aspect is the cooling system according to the ninth aspect, wherein the position of the guide member is changed so that the contact distance between the sheet and the cooling rotor is different.

[0146] [Method 11]

[0147] An eleventh aspect is the tenth aspect, wherein the position of the guide member is changed according to one of the type and thickness of the sheet.

[0148] [Method 12]

[0149] A twelfth aspect is an image forming system, comprising: the image forming apparatus according to any one of the first to eleventh aspects, and a control unit that controls the image forming apparatus.

Claims

1. An image forming device, characterized in that include: an image forming unit that forms an image on a sheet; a drying section for drying the sheet; a cooling section that cools the sheet, and an inspection section that inspects the sheet, The drying section, the cooling section, and the inspection section are provided at a lower portion of the image forming unit.

2. The image forming device according to claim 1, wherein: The drying section, the cooling section, and the inspection section are arranged so that at least a portion of each overlaps a portion of the image forming section when viewed from above in the vertical direction.

3. The image forming apparatus according to claim 1, wherein: The image forming section, the drying section, the cooling section, and the inspection section are provided in the same housing.

4. The image forming apparatus according to claim 1, wherein: The outlet of the drying section, the entire cooling section, and the inlet of the inspection section are arranged at a lower portion of the image forming section.

5. The image forming apparatus according to claim 1, wherein: The inlet of the image forming device is arranged below the outlet of the drying section and the entire cooling section.

6. The image forming apparatus according to claim 1, wherein: When the direction in which the sheet is conveyed in the image forming unit is defined as a first direction and a direction opposite to the first direction is defined as a second direction, The drying section, the cooling section, and the inspection section are arranged in this order in the second direction.

7. The image forming apparatus according to claim 1, wherein: The drying section includes a plurality of first heating rotating bodies with which the sheet material contacts twice from different directions, and a second heating rotating body with which the sheet material contacts once. At least three second heating rotating bodies are arranged on a path that guides the sheet having one surface in contact with the first heating rotating body and passing through the sheet so that one surface of the sheet is in contact with the first heating rotating body.

8. The image forming apparatus according to claim 1, wherein: An airflow is generated from the inspection section and the cooling section toward the drying section.

9. The image forming apparatus according to claim 1, wherein: The cooling unit includes a cooling rotating body that cools the sheet, and a guide member that guides the sheet.

10. The image forming apparatus according to claim 9, wherein: The position of the guide member is changed so that the contact distance between the sheet and the cooling rotor varies.

11. The image forming apparatus according to claim 10, wherein: The position of the guide member is changed according to one of the type and thickness of the sheet.

12. An image forming system, characterized in that include: The image forming apparatus according to claim 1, and A control unit controls the image forming apparatus.

Images