Image formation device and image formation system

Abstract

To reduce an installation space in a horizontal direction.SOLUTION: An image formation device 3 includes: an image formation part 7 for forming an image on a sheet S; a dry part 8 for drying the sheet S; a cooling part 9 for cooling the sheet S; and an inspection part 10 for inspecting the sheet S. The dry part 8, the cooling part 9 and the inspection part 10 are disposed in a lower part of the image formation part 7.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus and an image forming system. [Background technology]

[0002] 2. Description of the Related Art Some image forming systems that form an image on a sheet include an image forming section, a drying section that dries the sheet, a cooling section that cools the sheet, and the like.

[0003] For example, Patent Document 1 (JP 2020-1282 A) discloses an image forming system in which a drying section (drying unit) and a cooling section (cooling / transport unit) are arranged next to an image forming section (printing section).

[0004] In this manner, in a configuration in which units such as a drying section and a cooling section are disposed to the side of an image forming section, there is a problem in that the horizontal installation space increases. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an object of the present invention is to reduce the horizontal installation space. [Means for solving the problem]

[0006] In order to solve the above problems, the image forming apparatus of the present invention comprises an image forming unit that forms an image on a sheet, a drying unit that dries the sheet, a cooling unit that cools the sheet, and an inspection unit that inspects the sheet, and is characterized in that the drying unit, the cooling unit, and the inspection unit are arranged below the image forming unit. Effect of the Invention

[0007] According to the present invention, the horizontal installation space can be reduced. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing an overall configuration of an image forming system according to a first embodiment of the present invention. [Diagram 2] 2 is a block diagram showing a control unit of the image forming system according to the first embodiment of the present invention. FIG. [Diagram 3] 3 is a block diagram showing a more specific configuration of a control unit according to the first embodiment of the present invention. FIG. [Figure 4] FIG. 2 is a diagram showing a flow of an overall operation of the image forming system according to the first embodiment of the present invention. [Diagram 5] 1 is a schematic configuration diagram of an image forming apparatus according to a first embodiment of the present invention. [Figure 6] FIG. 2 is a schematic configuration diagram of a drying section according to the first embodiment of the present invention. [Figure 7] 3A to 3C are diagrams for explaining characteristic parts of a drying unit according to the first embodiment of the present invention. [Figure 8] FIG. 1 is a perspective view of an air blowing unit according to a first embodiment of the present invention. [Figure 9] FIG. 2 is a diagram showing an air supply and exhaust passage provided in a drying section according to the first embodiment of the present invention. [Figure 10] 5A and 5B are diagrams illustrating the direction of air currents generated within the image forming apparatus according to the first embodiment of the present invention. [Figure 11] FIG. 2 is a schematic configuration diagram of a cooling unit according to the first embodiment of the present invention. [Figure 12] 10A and 10B are diagrams illustrating an example in which the position of a guide roller is changed to adjust the contact distance between the cooling drum and the sheet in the conveying direction in the first embodiment of the present invention. [Figure 13] FIG. 2 is a schematic configuration diagram of an inspection unit according to the first embodiment of the present invention. [Figure 14] FIG. 6 is a diagram showing a configuration of a drying unit according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First, the overall configuration of an image forming system 100 according to a first embodiment of the present invention will be described with reference to Fig. 1. In each drawing for explaining the present invention, components such as members and parts having the same function or shape are given the same reference numerals as far as they can be distinguished, and the description thereof will be omitted after it has been described once.

[0010] <Image forming system configuration> As shown in FIG. 1, the image forming system 100 includes a sheet supplying device 1, a pre-processing device 2, a first tension adjusting device 17, a first image forming device 3, a front / back inversion device 4, a second image forming device 5, a second tension adjusting device 18, and a sheet recovery device 6.

[0011] The sheet supply device 1 includes a supply roller 11 around which a long sheet S is wound in a roll shape. When the supply roller 11 rotates in the direction of the arrow shown in FIG.

[0012] The pre-processing device 2 includes a treatment liquid application unit 12 that applies a treatment liquid to one or both sides of the sheet S. The treatment liquid is, for example, a liquid having a function of aggregating ink, and is applied to the sheet S for the purpose of improving image quality, such as preventing ink bleeding or assisting ink penetration.

[0013] The first tension adjusting device 17 is a device that transfers the sheet S from the pre-processing device 2 to the first image forming device 3 while adjusting the tension of the sheet S. The first tension adjusting device 17 has a plurality of rollers around which the sheet S is passed. The tension of the sheet S is adjusted by moving some of these rollers.

[0014] 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.

[0015] The image forming unit 7 has a plurality of inkjet type liquid ejection heads 13S, 13Y, 13M, 13C, and 13K, which are an example of a liquid ejection unit. In the example of FIG. 1, the liquid ejection head 13K for black ink, the liquid ejection head 13C for cyan ink, the liquid ejection head 13M for magenta ink, the liquid ejection head 13Y for yellow ink, and the liquid ejection head 13S for special color ink are arranged in this order from the upstream side in the sheet conveying direction in which the sheet S is conveyed. The special color ink is an ink other than black, cyan, magenta, and yellow, such as white or metallic, and is added appropriately depending on the application. The arrangement of the liquid ejection heads 13S, 13Y, 13M, 13C, and 13K is not limited to the order shown in FIG. 1, and may be in any order.

[0016] The drying section 8 has a heating rotor 20 that heats the sheet S. The heating rotor 20 is configured to rotate in association with the conveyance of the sheet S.

[0017] The cooling section 9 has a cooling rotor 30 that cools the sheet S. Like the heating rotor 20, the cooling rotor 30 is configured to rotate in association with the transport of the sheet S.

[0018] The inspection unit 10 has a scanner camera 14 that acquires position information of an image on the sheet S, and a colorimeter 15 that acquires color information of the image on the sheet S. The scanner camera 14 and the colorimeter 15 are examples of non-contact inspection devices that inspect the image on the sheet S, and only one of them may be provided, or other inspection devices may be provided. In the example shown in FIG. 1, the scanner camera 14 is disposed upstream of the colorimeter 15 in the sheet conveying direction, but conversely, the colorimeter 15 may be disposed upstream of the scanner camera 14 in the sheet conveying direction. The scanner camera 14 and the colorimeter 15 have detection units disposed across the entire width of the sheet S so that the entire width of the sheet S can be inspected. In addition, the scanner camera 14 preferably has a resolution equal to or greater than the resolution of the image.

[0019] The front / back reversing device 4 is configured by a known device that reverses the positions of the front and back sides of the sheet S.

[0020] The second image forming apparatus 5, like the first image forming apparatus 3, includes an image forming unit 7, a drying unit 8, a cooling unit 9, and an inspection unit 10. The configurations of the image forming unit 7, drying unit 8, cooling unit 9, and inspection unit 10 included in the second image forming apparatus 5 are basically the same as those of the image forming unit 7, drying unit 8, cooling unit 9, and inspection unit 10 included in the first image forming apparatus 3, so a description thereof will be omitted.

[0021] 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 configuration of the second tension adjusting device 18 is basically the same as that of the first tension adjusting device 17. In addition, the exterior of the upper parts of the first tension adjusting device 17, the front / back inverting device 4, and the second tension adjusting device 18 is recessed toward the back side in FIG. 1, ensuring a space large enough for an operator to enter. Therefore, an operator can stand on the first tension adjusting device 17, the front / back inverting device 4, or the second tension adjusting device 18 to operate a control panel or perform maintenance work.

[0022] The sheet collection device 6 has a collection roller 16 that winds up and collects the sheet S. When the collection roller 16 rotates in the direction of the arrow shown in FIG.

[0023] <Control Unit Configuration> FIG. 2 is a block diagram showing a control unit 200 of the image forming system 100 according to the first embodiment of the present invention.

[0024] 2, the image forming system 100 includes a control unit 200 that controls various operations of the sheet supply device 1, the pre-processing device 2, the first tension adjusting device 17, the first image forming device 3, the front / back reversing device 4, the second image forming device 5, the second tension adjusting device 18, and the sheet recovery device 6. For example, the control unit 200 controls the rotation speed of the supply roller 11, the ink discharge operation of each liquid discharge head 13Y, 13M, 13C, and 13K, the heating temperature of the heating rotor 20, the cooling temperature of the cooling rotor 30, the rotation speed of the recovery roller 16, and the tension applied to the sheet S. 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 scanner camera 14 of the inspection unit 10 and the color information of the image acquired by the colorimeter 15.

[0025] FIG. 3 is a block diagram showing a more specific configuration of the control unit 200 according to the first embodiment of the present invention.

[0026] As shown in FIG. 3, 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 line 66, a main scanning driver 67, a sub-scanning driver 68, a liquid ejection driver 69, and an operation panel 70.

[0027] The CPU 60 controls the overall operation of the image forming system 100. The ROM 61 stores programs such as an IPL used to drive the CPU 60. The RAM 62 is used as a work area for the CPU 60. The NVRAM 63 stores various data such as programs, and retains the various data even when the power to the image forming system 100 is cut off.

[0028] 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 line 66 is an address bus and a data bus for electrically connecting each component such as the CPU 60.

[0029] The main scanning driver 67 controls the movement in the main scanning direction of the carriage 130 carrying the liquid ejection head 13. The "main scanning direction" here means the width direction of the sheet, and a direction perpendicular to the sheet transport direction on a plane parallel to the sheet.

[0030] 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 for driving the roller, and conveys the sheet S intermittently in a sub-scanning direction, which is the sheet conveying direction. While the sheet S is intermittently conveyed in the sub-scanning direction under the control of the sub-scanning driver 68, the carriage 130 moves in the main scanning direction under the control of the main scanning driver 67, and ink is ejected from the liquid ejection head 13, thereby forming an image on the sheet S.

[0031] 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 line 66 outside the carriage 130. Furthermore, the main scanning driver 67, the sub-scanning driver 68, and the liquid ejection driver 69 may each be a function realized by an instruction from the CPU 60 according to a program.

[0032] The operation panel 70 displays current settings and a selection screen, and is configured with a touch panel for receiving input from an operator, an alarm lamp, and the like.

[0033] <Overall operation of the image forming system> FIG. 4 is a diagram showing the flow of the entire operation of the image forming system 100 according to the first embodiment of the present invention.

[0034] When the operation of the image forming system 100 is started, the supply roller 11 of the sheet supply device 1 rotates to supply the sheet S from the supply roller 11, thereby carrying out a "sheet supplying process."

[0035] Then, the sheet S is conveyed to the pre-processing device 2, where the pre-processing device 2 applies the treatment liquid to the sheet S by the treatment liquid application section 12 of the pre-processing device 2, thereby carrying out a "pre-processing step."

[0036] Next, the sheet S is transported to the first image forming apparatus 3 via the first tension adjusting device 17. Then, in the first image forming apparatus 3, each process A of an "image forming process" for forming an image on the sheet S, a "drying process" for drying the sheet S, a "cooling process" for cooling the sheet S, and an "inspection process" for inspecting the sheet S are sequentially performed. First, in the "image forming process", the sheet S is transported to the image forming section 7 in the first image forming apparatus 3, and ink is ejected from each ejection head 13, 13Y, 13M, 13C, and 13K onto a first surface (front surface) of the sheet S, and an image is formed on the first surface.

[0037] Next, the sheet S is transported to the drying section 8 in the first image forming apparatus 3, and a "drying process" is performed by the drying section 8. In the drying section 8, the transported sheet S is heated by contacting the surface of the heating rotator 20. This causes the liquid component of the ink on the sheet S to evaporate, and the sheet S is dried.

[0038] Subsequently, the sheet S is conveyed to the cooling section 9 in the first image forming apparatus 3, and a "cooling step" is performed by the cooling section 9. In the cooling section 9, the conveyed sheet S comes into contact with the surface of the cooling rotor 30, whereby the sheet S is cooled.

[0039] Furthermore, the sheet S is conveyed to an inspection unit 10 in the first image forming apparatus 3, and an "inspection process" is performed by the inspection unit 10. In the "inspection process", position information of the image on the sheet S is obtained by a scanner camera 14, and color information of the image on the sheet S is obtained by a colorimeter 15.

[0040] Thereafter, the sheet S is conveyed to a front / back reversing device 4, where the front / back of the sheet S is reversed by the front / back reversing device 4, in a "front / back reversing step."

[0041] The inverted sheet S is transported to the second image forming apparatus 5. That is, in the second image forming apparatus 5, the sheet S is transported so that the second surface (back surface) opposite to the first surface faces the ejection heads 13, 13Y, 13M, 13C, and 13K. Therefore, when the sheet S is transported to the second image forming apparatus 5, ink is ejected onto the second surface of the sheet S, and an image is formed on the second surface. In addition to the "image forming process", the second image forming apparatus 5 also performs each of the steps B, namely, the "drying process", the "cooling process", and the "inspection process", in the same manner as the first image forming apparatus 3. The basic operations of the "image forming process", "drying process", "cooling process", and "inspection process" in the second image forming apparatus 5 are the same as the basic operations of each of the steps A in the first image forming apparatus 3, and therefore will not be described.

[0042] Thereafter, the sheet S is conveyed to the sheet recovery device 6 via the second tension adjusting device 18, and a "sheet recovery process" is performed. In the "sheet recovery process", the sheet S is wound up and recovered by the recovery roller 16. This completes a series of operations of the image forming system 100.

[0043] As described above, in the image forming system 100 according to the first embodiment of the present invention, an "inspection process" is performed to acquire image position information and color information for each of the first image forming device 3 and the second image forming device 5, so that defective images can be automatically detected. For example, from the image position information acquired by the scanner camera 14, it is possible to detect not only the positional deviation between the target image and the actual image on each of the first and second sides of the sheet S, but also the relative positional deviation and image size deviation of each image on the first and second sides. In addition, from the color information of the image acquired by the colorimeter 15, it is also possible to detect color unevenness, color loss, etc. on each of the images on the first and second sides.

[0044] Also, the results obtained by each "inspection process" may be fed back to the "image forming process" of the first image forming apparatus 3 and the second image forming apparatus 5 by the control unit 200, and image formation may be performed based on the corrected image data or image forming conditions. This makes it possible to suppress the occurrence of image position and color unevenness. Also, based on the results obtained by the "inspection process" of the first image forming apparatus 3, the control unit 200 may feedforward control the "image forming process" of the second image forming apparatus 5. In this case, it is possible to suppress the positional deviation of the images on the first side and the second side, and to improve the image quality. Furthermore, the feedback control and the feedforward control based on the inspection results may be selectively executed according to the image forming conditions or the image forming mode. Also, when a defective image occurs, the location of the defective image may be marked on the sheet S or information on the defective image may be recorded so that an operator or the like can check the location of the defect or the state of the defect after the sheet is collected. Thus, in the first embodiment of the present invention, the image forming system 100 is provided with the inspection unit 10 that automatically inspects the image, thereby making it possible to improve the image quality and reduce the monitoring or inspection burden on the operator.

[0045] <Issues in image forming systems> However, in an image forming system equipped with multiple devices such as a sheet feeder, a pre-processing device, and an image forming device, if the devices are arranged side by side, the horizontal installation space increases, which creates a problem of restrictions on the installation of the image forming system. In particular, in fields such as commercial printing, where large devices are used, the problem of installation space becomes prominent.

[0046] In addition, in the conventional configuration, there is a case where an inspection device is added as an optional unit as necessary. In that case, since the inspection device is generally arranged side by side with the peripheral devices, the addition of the inspection device causes a problem of increasing the installation space of the entire image forming system. In addition, when the inspection device is separate from the other devices, the position of the inspection device may be shifted relative to the peripheral devices when the inspection device is added, and the image on the sheet may not be inspected with high accuracy. In addition, while it is preferable to inspect the image in a stable state immediately after the sheet is dried and cooled, when the inspection device is separate, the conveying distance of the sheet from the drying device and the cooling device to the inspection device becomes long, which causes a problem of making it difficult to inspect the image immediately after drying and cooling.

[0047] Therefore, the present invention has as its first object to reduce the horizontal installation space in the image forming system, and as its second object to improve the inspection accuracy. Below, the characteristic features of the present invention will be described using the configuration according to the first embodiment of the present invention as an example.

[0048] <Configuration of Characteristic Part According to the First Embodiment of the Present Invention> FIG. 5 is a schematic diagram of an image forming apparatus 3 according to the first embodiment of the present invention.

[0049] First, the layout of the image forming unit 7, drying unit 8, cooling unit 9, and inspection unit 10 will be described with reference to Fig. 5. Here, the configuration of the first image forming apparatus 3 will be described as an example, and the configuration of the second image forming apparatus 5 is the same as that of the first image forming apparatus 3, so the description will be omitted.

[0050] 5, in the first image forming apparatus 3, the drying section 8, the cooling section 9, and the inspection section 10 are disposed below the image forming section 7. Here, "below" the image forming section 7 means that the drying section 8, the cooling section 9, and the inspection section 10 are disposed below the image forming section 7 such that 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 when viewed from above in the vertical direction. Therefore, in addition to the case where the entirety of each of the drying section 8, the cooling section 9, and the inspection section 10 overlaps with the image forming section 7 when viewed from above in the vertical direction, the case where only 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 may also be used.

[0051] 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 disposed below the image forming section 7. In addition, if the direction in which the sheet S is conveyed in the image forming section 7 is defined as a first direction Y1, and the opposite direction to the first direction Y1 is defined as a second direction Y2, the drying section 8, the cooling section 9, and the inspection section 10 are disposed in this order toward the second direction Y2. For this reason, 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 disposed below 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 housing 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. Moreover, the "entrance D of the inspection section 10" is, for example, a portion where the sheet S enters the inspection range (detection range) of the scanner camera 14, and also includes a transfer portion or a connection portion where the sheet S is transferred from the cooling section 9 to the inspection section 10. The entrance J of the image forming apparatus is disposed below the exit C of the drying section 8 and the entire cooling section 9. The "entrance J of the image forming apparatus" here refers to a connection portion or a transfer portion between the image forming apparatus and the nearest device located upstream in the sheet conveying direction. For example, in the case of the first image forming apparatus 3, the connection portion or the transfer portion between the first image forming apparatus 3 and the first tension adjusting device 17 corresponds to the entrance of the first image forming apparatus 3, and in the case of the second image forming apparatus 5, the connection portion or the transfer portion between the second image forming apparatus 5 and the front-back reversing device 4 corresponds to the entrance of the second image forming apparatus 5. Moreover, "below the exit C of the drying section 8 and the entire cooling section 9" means a position lower than the exit C of the drying section 8 and the entire cooling section 9 in the vertical direction.

[0052] In this way, in the first embodiment of the present invention, the drying unit 8, cooling unit 9, and inspection unit 10 are disposed below the image forming unit 7, so that the horizontal installation space can be reduced compared to the case where these are disposed horizontally next to the image forming unit 7. Therefore, according to the first embodiment of the present invention, there is less restriction on the installation area, making it easier to install the image forming system and also easier to add other devices as necessary.

[0053] 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 in the second direction Y2, so that a transport path is formed that efficiently transports the sheet S from the image forming section 7 to the drying section 8, the cooling section 9, and the inspection section 10 in sequence. That is, the sheet S is transported in the first direction Y1 in the image forming section 7, and then transported in the second direction Y2 from the drying section 8 to the cooling section 9 and the inspection section 10 so as to be folded back, so that the transport path of the sheet S is not unnecessarily long and the sheet S can be transported efficiently. 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 the first direction Y1 in this order, and is then carried out. In this way, in the first embodiment of the present invention, the layout of the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 is determined so that the sheet S can be efficiently transported in the first image forming device 3, so that the device can be made compact. In addition, the transport distance of the sheet S transported from the drying section 8 and the cooling section 9 to the inspection section 10 can be shortened, so that the image can be inspected in a stable state immediately after the sheet S has been dried and cooled, improving the inspection accuracy.

[0054] Depending on the layout of 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 in the first direction Y1, 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 as appropriate.

[0055] In the first embodiment of the present invention, the drying section 8, the cooling section 9, and the inspection section 10 are disposed below 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 disposed in the same housing 19 provided in the first image forming device 3. This allows the device to be made smaller than a configuration in which the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 each have their own housing and the housings are disposed with their outer surfaces facing each other. That is, since the image forming section 7, the drying section 8, the cooling section 9, and the inspection section 10 are disposed in the same housing 19, it becomes easier to arrange the devices and members close to each other, so that the devices and members can be arranged efficiently and the size can be reduced. Note that the "same housing" is not limited to a case where it is constituted by one exterior member, but may be a case where it is constituted by multiple exterior members. Also, each component member disposed in the same housing does not have to be held by the same (single) side plate. That is, the present invention also includes a case in which each component member is held by multiple side plates.

[0056] In the first embodiment of the present invention, the inspection unit 10 is not a separate unit having a housing separate from the image forming unit 7, the drying unit 8, and the cooling unit 9, but is configured as an integrated unit provided in the same housing 19, so that the inspection accuracy of the inspection unit 10 is improved. That is, since the inspection unit 10 is provided integrally with the image forming unit 7, the drying unit 8, and the cooling unit 9, the relative position of the inspection unit 10 with respect to the image forming unit 7, the drying unit 8, and the cooling unit 9 is fixed, so that the positional deviation of the inspection unit 10 can be prevented and the image on the sheet S can be inspected with high accuracy. In addition, the transport distance of the sheet S transported from the drying unit 8 and the cooling unit 9 to the inspection unit 10 can be shortened, so that the image can be inspected in a stable state immediately after the sheet S is dried and cooled, and the inspection accuracy is improved. This improves the reliability of the image inspection.

[0057] As described above, in the first embodiment of the present invention, the horizontal installation space can be reduced and the inspection accuracy can be improved. However, since the drying unit 8, the cooling unit 9, and the inspection unit 10 are disposed below the image forming unit 7, there is a concern that the first image forming device 3 will become larger in the vertical direction. Since an increase in the vertical size leads to a decrease in the ease of handling during storage and transportation of the image forming device, as well as a decrease in ease of assembly and maintenance, it is preferable to suppress the increase in the vertical size.

[0058] Therefore, in the first embodiment of the present invention, the following measures are taken to prevent the image forming apparatus from becoming larger in the vertical direction. Below, the configurations of the drying unit 8, cooling unit 9, and inspection unit 10 according to the first embodiment of the present invention will be described in detail, including the measures to prevent the image forming apparatus from becoming larger in the vertical direction.

[0059] <Drying section configuration> FIG. 6 is a schematic configuration diagram of the drying section 8 according to the first embodiment of the present invention.

[0060] As shown in FIG. 6, the drying section 8 includes a heating roller 21, a heating drum 22, a guide roller 23, and an air blowing unit 24.

[0061] The heating roller 21 and the heating drum 22 are heating rotors 20 having heating sources 250, 260 such as halogen heaters inside. The heating drum 22 is a heating rotor 20 having a larger diameter than the heating roller 21, and one is disposed near the center of the drying section 8. In addition, a plurality of heating rollers 21 are disposed in a spiral shape around the heating drum 22.

[0062] Unlike the heating roller 21 and the heating drum 22, the guide roller 23 does not have a heat source inside, and is a rotating body that functions as a guide member that guides 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.

[0063] The air blowing unit 24 is a blowing means that blows air onto the sheet S to promote drying of the sheet S. A plurality of air blowing units 24 are arranged so as to face the sheet S stretched by the heating roller 21, the heating drum 22, and the guide roller 23.

[0064] When the sheet S is conveyed into the drying section 8, the sheet S is first passed over the outside of the plurality of heating rollers 21. The "outside" of the heating roller 21 here means the side of the outer circumferential surface of the heating roller 21 opposite to the side facing the heating drum 22. The sheet S is then conveyed while being in contact with the outside of the heating roller 21, and is then wrapped around the heating drum 22. Thereafter, the sheet S is passed over the guide roller 23 from the heating drum 22, and conveyed while being in contact with the inside of the plurality of heating rollers 21 (the side facing the heating drum 22). As a result, the sheet S is conveyed so that the side opposite to the image forming surface comes into contact with the outside of the heating roller 21, the heating drum 22, and the inside of the heating roller 21 in sequence, and is heated from the side opposite to the image forming surface. Furthermore, air is blown onto the image forming surface of the sheet S by the plurality of air blowing units 24. As a result, the sheet S is dried. Thereafter, the sheet S is guided by the guide roller 23 and conveyed out of the drying section 8.

[0065] 7, in the first embodiment of the present invention, the multiple heating rollers 21 are arranged within an elliptical locus E. In this manner, by arranging the multiple heating rollers 21 within the elliptical locus E, the vertical dimension (height) of the drying unit 8 can be reduced. That is, by arranging the multiple heating rollers 21 within the elliptical locus E, the maximum vertical dimension H of the area in which each heating roller 21 is arranged can be made smaller than the maximum horizontal dimension W when viewed from the axial direction of each heating roller 21, so that the vertical size of the drying unit 8 can be reduced. This also makes it possible to reduce the vertical size of the entire first image forming apparatus 3 including the drying unit 8.

[0066] Furthermore, in the first embodiment of the present invention, after the sheet S is guided in a spiral shape (counterclockwise in FIG. 7) by the multiple heating rollers 21, the sheet S is redirected starting from the heating drum 22 and guided in the opposite direction in a spiral shape (clockwise in FIG. 7) by the multiple guide rollers 23. In this way, the sheet S is redirected and transported in the drying unit 8, so that the sheet S can be efficiently heated even in a small space, and high drying performance can be obtained.

[0067] In order to realize such a compact conveying path for the sheet S, in the first embodiment of the present invention, the direction changing portion F for the sheet S is configured as follows.

[0068] Here, the heating rotator 20 including each heating roller 21 and heating drum 22 includes a first heating rotator with which the sheet S comes into contact twice from different directions, and a second rotator with which the sheet S comes into contact only once. In this case, the first rotator is the heating roller 21A (hatched heating roller 21A in FIG. 7) with which the sheet S comes into contact twice, and the second rotator is the heating roller 21B (not hatched heating roller 21B in FIG. 7) with which the sheet S comes into contact only once, and the heating drum 22. The sheet S is conveyed while coming into contact with the multiple heating rollers 21A (hatched) that are the first heating rotator, and then changes direction via the three heating rollers 21B (not hatched) and one heating drum 22 that are the second rotator, and is conveyed again while coming into contact with the heating rollers 21A (hatched) that are the first heating rotator.

[0069] In this manner, in the first embodiment of the present invention, the direction changing section F, which brings one side of the sheet S into contact with each of the heating rollers 21A (hatched), which are the first heating rotators, again, is configured by three heating rollers 21B (not hatched), which are the second heating rotators, and one heating drum 22. This realizes a compact sheet transport path while ensuring high drying performance, thereby making the device more compact.

[0070] FIG. 8 is a perspective view of the air blowing unit 24 according to the first embodiment of the present invention.

[0071] 8, air blowing unit 24 has blow holes 25 and intake holes 26 on surface 240 disposed so as to face the sheet. Air blowing unit 24 also has blow duct 27 and intake duct 28 inside. Blowing duct 27 communicates with blow holes 25, and intake duct 28 communicates with intake holes 26.

[0072] FIG. 9 is a diagram showing an air supply / exhaust flow path 40 provided in the drying section 8 according to the first embodiment of the present invention.

[0073] 9, drying unit 8 is provided with an air supply / exhaust flow path 40 that draws in air from the front side (right side of the figure) and the rear side (left side of the figure), supplies the air to the inside, and exhausts the air from the rear side. Specifically, air supply / exhaust flow path 40 has air supply holes 41A, 41B provided on the front side and the rear side, air supply ducts 42A, 42B communicating with air supply holes 41A, 41B, an exhaust hole 43 provided on the rear side, and exhaust ducts 44A, 44B, 44C communicating with exhaust hole 43.

[0074] The air supply ducts 42A, 42B extend radially from the air supply holes 41A, 41B on the front and rear sides, and are connected to both ends of the air blowing duct 27 of each air blowing unit 24. This forms an air supply path that passes air from each air supply hole 41A, 41B to each air blowing unit 24 via the air supply ducts 42A, 42B.

[0075] The exhaust ducts 44A, 44B, 44C include a front exhaust duct 44A extending radially on the front side, a rear exhaust duct 44B extending radially on the rear side, and a central exhaust duct 44C passing through the center of the drying section 8. The front and rear exhaust ducts 44A, 44B are connected to both ends of the blower duct 27 of each air blowing unit 24. In addition, the front and rear exhaust ducts 44A, 44B communicate with the exhaust hole 43 via the central exhaust duct 44C. This forms an exhaust path that passes air from each air blowing unit 24 to the exhaust hole 43 via the exhaust ducts 44A, 44B, 44C.

[0076] As shown by the arrows in Fig. 9, when air is sucked in through the air supply holes 41A, 41B on the front and rear sides, the air passes through the air supply ducts 42A, 42B on the front and rear sides and is sent to the air supply ducts 27 of each blowing unit 24. The air is then blown out from the air supply holes 25 and directed at the sheet, thereby accelerating the drying of the sheet.

[0077] Furthermore, air containing water vapor and the like generated from the sheet as it is dried is sucked in through the intake holes 26 of each blowing unit 24. The air sucked in through the intake holes 26 passes through the intake ducts 28 of each blowing unit 24 and the exhaust ducts 44A, 44B on the front and rear sides, is collected in the central exhaust duct 44C, and is exhausted through the exhaust holes 43. As a result, air containing water vapor and the like is exhausted from inside the drying section 8 to the outside, so that the humidity environment inside the drying section 8 can be maintained at an appropriate level.

[0078] As described above, in the first embodiment of the present invention, the air supply and exhaust flow path 40 is provided to supply air into the drying section 8 and exhaust air from the drying section 8, so that the air supply and exhaust by the drying section 8 generates an air flow from the cooling section 9 and the inspection section 10 toward the drying section 8 as shown by the arrows in FIG. 10. In the cooling section 9 and the inspection section 10, water vapor and the like may be generated from the sheet S, although not as much as in the drying section 8. Therefore, by generating an air flow from the cooling section 9 and the inspection section 10 toward the drying section 8, the water vapor and the like can be moved to the drying section 8. As a result, the humidity environment can be appropriately maintained in the cooling section 9 and the inspection section 10 as well. In addition, dust and the like floating around the inspection section 10 can be moved toward the drying section 8 by the air flow, so that the dust and the like can be prevented from adhering to the detection section of the scanner camera 14 and the colorimeter 15, and good inspection accuracy can be maintained.

[0079] <Cooling section configuration> FIG. 11 is a schematic configuration diagram of a cooling section 9 according to the first embodiment of the present invention.

[0080] As shown in FIG. 11, the cooling unit 9 includes a cooling drum 31 and a guide roller 32.

[0081] The cooling drum 31 is an example of the cooling rotor 30. The cooling drum 31 is configured of a rotor having a larger diameter than the guide roller 32, and has a refrigerant flow path therein through which a refrigerant such as cooling water passes. In this case, two cooling drums 31 are arranged vertically side by side. Note that the number and arrangement of the cooling drums 31 are not limited to the example shown in FIG. 11.

[0082] The guide roller 32 is an example of a guide member that guides the sheet S. In this case, a plurality of guide rollers 32 are arranged around the cooling drum 31, but there may be only one guide roller. The sheet S is guided by the guide rollers 32 and wrapped around the outer circumferential surface of each cooling drum 31, whereby the sheet S is cooled.

[0083] Incidentally, the ease with which the sheet S is cooled varies depending on its thickness or type. For example, cardboard that is thicker than plain paper is more difficult to cool than plain paper, and so tends to take a longer time to cool. For this reason, in the first embodiment of the present invention, the position of the guide roller 32 is made changeable, and the contact distance (wrap-around length) of the sheet S in the conveying direction relative to the cooling drum 31 can be adjusted.

[0084] For example, by changing the position of the guide roller 32B from the state shown in Fig. 12(a) to the state shown in Fig. 12(b), it is possible to shorten the contact distance L of the sheet S in the transport direction with respect to the upper cooling drum 31. Furthermore, when the position of the guide roller 32B is changed from the position in Fig. 12(a) to the position in Fig. 12(c), it is possible to shorten the contact distance L of the sheet S in the transport direction with respect to both the upper and lower cooling drums 31.

[0085] In this way, in the first embodiment of the present invention, the contact distance L of the sheet S in the conveying direction with respect to the cooling drum 31 can be adjusted by changing the position of the guide roller 32. In this way, when the sheet S is difficult to cool, the contact distance L of the sheet S in the conveying direction with respect to the cooling drum 31 is increased to ensure a long cooling time, and conversely, when the sheet S is easy to cool, the contact distance L of the sheet S in the conveying direction with respect to the cooling drum 31 is decreased to shorten the cooling time, thereby enabling cooling according to the thickness or type of the sheet S. In addition, since the contact distance L of the sheet S in the conveying direction can be adjusted in a small space, the device can be made compact. In addition, in the first embodiment of the present invention, the cooling unit 9 is disposed in the housing 19 (see FIG. 10) of the first image forming device 3 and does not have its own housing, so that the degree of freedom in changing the position of the guide roller 32 is improved. In other words, the position of the guide roller 32 can be changed widely without being restricted by the size of the own housing. This allows the cooling capacity to be optimized.

[0086] The position of the guide roller 32 may be changed based on not only the information on the type or thickness of the sheet S but also on both of them. The position of the guide roller 32 may be changed manually by an operator or automatically by using a well-known moving mechanism including an eccentric cam and a spring. In addition to changing the position of the guide roller 32, the contact distance L of the sheet S in the conveying direction with respect to the cooling drum 31 can also be adjusted by changing the number of the guide rollers 32.

[0087] <Inspection Department Configuration> FIG. 13 is a schematic configuration diagram of an inspection unit 10 according to the first embodiment of the present invention.

[0088] As shown in FIG. 13, the inspection unit 10 has a scanner camera 14, a colorimeter 15, and a plurality of guide rollers 50.

[0089] The guide rollers 50 are an example of a guide member that guides the sheet S, and are disposed above the scanner camera 14 and 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 scanner camera 14 and the colorimeter 15. At this time, the scanner camera 14 and the colorimeter 15 are disposed so that their respective detection surfaces 14a, 15a facing the image forming surface of the sheet S face substantially horizontally in order to inspect the image on the sheet S that is guided downward.

[0090] In this way, in the first embodiment of the present invention, the respective detection surfaces 14a, 15a of the scanner camera 14 and the colorimeter 15 are arranged to face in a substantially horizontal direction, so that water vapor and dust are less likely to adhere to each of the detection surfaces 14a, 15a. This makes it possible to avoid variations in detection accuracy or a decrease in detection accuracy due to water vapor adhering to each of the detection surfaces 14a, 15a, and improves inspection accuracy. In addition, in the first embodiment of the present invention, the scanner camera 14 and the colorimeter 15 are arranged at positions that do not overlap with the range vertically above each of the cooling drums 31, so that water vapor generated in the cooling section 9 can also be prevented from adhering to each of the detection surfaces 14a, 15a.

[0091] <Configuration of the second embodiment of the present invention> FIG. 14 is a diagram showing the configuration of the drying section 8 according to the second embodiment of the present invention.

[0092] The drying unit included in the image forming apparatus according to the present invention may be the drying unit 8 shown in Fig. 14 in addition to the drying unit 8 shown in Fig. 6 and Fig. 7. The drying unit 8 shown in Fig. 14 has two heating drums 22, a plurality of heating rollers 21, and a plurality of guide rollers 23.

[0093] In this case, the heating roller 21 and the guide roller 50 are arranged along an elliptical locus E, rather than a spiral shape, around the heating drum 22. Even when the heating rollers 21 are arranged along an elliptical locus E in this way, the maximum vertical dimension H of the area in which the heating rollers 21 are arranged can be made smaller than the maximum horizontal dimension W, so that the drying unit 8 can be made smaller in size in the vertical direction.

[0094] Also, in the example shown in FIG. 14, when the sheet S is transported into the drying section 8, the sheet S is transported while in contact with a plurality of heating rollers 21A (hatched) which are the first heating rotators, and then the sheet S is changed direction via one heating roller 21B (not hatched) which is the second rotator and two heating drums 22, and is transported while being guided by a plurality of guide rollers 23 so as to come into contact with each of the heating rollers 21A (hatched) which are the first heating rotators again.

[0095] In this case, one heating roller 21B (not hatched) and two heating drums 22 that the sheet S comes into contact with only once function as a second heating rotator that changes the direction of the sheet S and brings one side of the sheet S into contact with each heating roller 21A (hatched), which is the first heating rotator. That is, in this case, three second rotators, one heating roller 21B and two heating drums 22, constitute the direction changing section F that changes the direction of the sheet S. In this way, by forming the direction changing section F with three second heating rotators, a compact sheet transport path can be realized while ensuring high drying performance. Note that the number of second rotators arranged on a path that guides a sheet that has passed while one side is in contact with the first heating rotator so that the same side comes into contact with the first heating rotator again, that is, the number of second heating rotators that constitute the direction changing section F, may be three, or may be four as in the example shown in FIG. 7, or may be five or more.

[0096] Although the embodiments of the image forming system and image forming device according to the present invention have been described above, the image forming system and image forming device according to the present invention are not limited to the above-mentioned embodiments. The image forming system and image forming device according to the present invention are not limited to those that visualize significant images such as characters and figures by ejected liquid, but may also form patterns that have no meaning in themselves. Furthermore, the image referred to in the present invention is not limited to characters, line drawings, photographs, etc., but also includes circuit patterns formed on a printed circuit board, symbol diagrams, etc.

[0097] The image forming system according to the present invention may be one that forms an image on a long continuous sheet, and then winds up and collects the sheet, and may also be one that includes a post-processing device that cuts the sheet after image formation.The image forming system according to the present invention may be one that forms an image on a sheet that has been cut to a predetermined size in advance.

[0098] The liquid ejection unit of the image forming apparatus according to the present invention may eject liquid while moving, or may eject liquid without moving. Specific examples include a serial type liquid ejection head that ejects liquid while moving in the sheet width direction toward a stationary sheet, and a line type liquid ejection head that ejects liquid while stationary toward a moving sheet.

[0099] The liquid discharged from the liquid discharge unit may have any viscosity or surface tension that allows discharge, and is not particularly limited, but is preferably one whose viscosity is 30 mPa s or less at room temperature and pressure, or by heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, etc., containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a functionalizing material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, amino acids, proteins, or calcium, or an edible material such as a natural colorant.

[0100] The sheet used in the present invention is one to which a liquid can adhere at least temporarily, and includes one to which the liquid adheres and sticks, and one to which the liquid adheres and penetrates. Specific examples include recording media such as paper, recording paper, film, and cloth, and electronic boards. Examples of the material of the sheet include paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, and ceramics. The sheet may be in a form in which it is transported continuously from the sheet supply device to the sheet recovery device without interruption, or in a form in which it is transported independently one sheet at a time from the sheet supply device to the sheet recovery device without continuous transport.

[0101] To summarize the above-described aspects of the present invention, the present invention includes at least the following aspects.

[0102] [First aspect] The first aspect is an image forming device comprising an image forming unit that forms an image on a sheet, a drying unit that dries the sheet, a cooling unit that cools the sheet, and an inspection unit that inspects the sheet, wherein the drying unit, the cooling unit, and the inspection unit are disposed below the image forming unit.

[0103] [Second aspect] In a second aspect, in the first aspect, the drying section, the cooling section, and the inspection section are arranged so that at least a portion of each of them overlaps a portion of the image forming section when viewed from above in the vertical direction.

[0104] [Third aspect] In a third aspect, in the first or second aspect, the image forming unit, the drying unit, the cooling unit, and the inspection unit are provided in a same housing.

[0105] [Fourth aspect] In a fourth aspect, in any one of the first to third aspects, an outlet of the drying section, the entire cooling section, and an inlet of the inspection section are disposed below the image forming section.

[0106] [Fifth aspect] A fifth aspect is any one of the first to fourth aspects, wherein an inlet of the image forming device is disposed lower than an outlet of the drying section and the entire cooling section.

[0107] [Sixth aspect] In a sixth aspect, when the direction in which the sheet is transported in the image forming unit of any one of the first to fifth aspects is defined as a first direction and the direction opposite to the first direction is defined as a second direction, the drying unit, the cooling unit, and the inspection unit are arranged in the following order toward the second direction: drying unit, cooling unit, inspection unit.

[0108] [Seventh aspect] A seventh aspect is any one of the first to sixth aspects, wherein the drying section has a plurality of first heating rotators with which the sheet comes into contact twice from different directions and a second heating rotator with which the sheet comes into contact once, and at least three of the second heating rotators are arranged in a path that guides the sheet that has passed through the first heating rotators with one side in contact with the first heating rotators so that one side of the sheet comes into contact with the first heating rotators.

[0109] [Eighth aspect] An eighth aspect is any one of the first to seventh aspects, wherein an airflow is generated from the inspection unit and the cooling unit toward the drying unit.

[0110] [Ninth aspect] A ninth aspect is any one of the first to eighth aspects, wherein the cooling section has a cooling rotor that cools the sheet, and a guide member that guides the sheet.

[0111] [Tenth aspect] In a tenth aspect, in the ninth aspect, a position of the guide member is changed to vary a contact distance of the sheet with respect to the cooling rotor.

[0112] [Eleventh aspect] In an eleventh aspect, in the tenth aspect, the position of the guide member is changed based on at least one of the type and thickness of the sheet.

[0113] [Twelfth aspect] A twelfth aspect is an image forming system including the image forming apparatus according to any one of the first to eleventh aspects, and a control unit that controls the image forming apparatus. [Explanation of symbols]

[0114] 3. First Image Forming Apparatus 5. Second image forming device 7 Image forming section 8 Drying section 9 Cooling section 10. Inspection Department 19. Cabinet 20 Heating Rotor 21 Heating roller (heating rotor) 21A Heating roller (first heating rotating body) 21B Heating roller (second heating rotating body) 22 Heating drum (second heating rotor) 30 Cooling Rotor 31 Cooling drum (cooling rotor) 32 Guide roller (guide member) 100 Image forming system 200 Control section C Exit of drying section D Inspection Department Entrance L Sheet contact distance S Seat Y1 First direction Y2 Second direction [Prior art documents] [Patent documents]

[0115] [Patent Document 1] JP 2020-1282 A

Claims

1. an image forming unit that forms an image on a sheet; A drying section for drying the sheet; A cooling unit that cools the sheet; an inspection unit that inspects the sheet, 13. An image forming apparatus, comprising: a drying unit, a cooling unit, and an inspection unit disposed below the image forming unit.

2. 2 . The image forming apparatus according to claim 1 , wherein the drying section, the cooling section, and the inspection section are disposed such that at least a portion of each of them 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 a single housing.

4. 2. The image forming apparatus according to claim 1, wherein an outlet of the drying section, the entire cooling section, and an inlet of the inspection section are disposed below the image forming section.

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

6. When a 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, 2 . The image forming apparatus according to claim 1 , wherein the drying unit, the cooling unit, and the inspection unit are arranged in the following order in the second direction: the drying unit, the cooling unit, and the inspection unit.

7. The drying section includes: a plurality of first heating rotors with which the sheet comes into contact twice from different directions; a second heating rotor with which the sheet comes into contact once; 2. The image forming apparatus according to claim 1, wherein at least three of the second heating rotors are arranged in a path that guides the sheet that has passed through the first heating rotor with one side in contact with the first heating rotor so that one side of the sheet comes into contact with the first heating rotor.

8. The image forming apparatus according to claim 1 , wherein an air current is generated from the inspection unit and the cooling unit toward the drying unit.

9. The cooling unit includes: A cooling rotor that cools the sheet; 2. The image forming apparatus according to claim 1, further comprising a guide member for guiding the sheet.

10. 10. The image forming apparatus according to claim 9, wherein the position of the guide member is changed to vary a contact distance of the sheet with respect to the cooling rotor.

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

12. The image forming apparatus according to claim 1 ; A control unit that controls the image forming apparatus; An image forming system comprising:

Images