Drying device

Abstract

To provide a drying device that dries a medium while conveying the same in a stable manner.SOLUTION: A drying device 1 is equipped with a conveying device 3 that conveys an image-formed medium in a predetermined transport direction, an air blower 5 that dries the medium by blowing air from above while being conveyed by the conveying device 3, and an exhaust device 7 that takes in and exhausts air above the medium from both sides of the conveying device 3 in the width direction of the medium that intersects with the conveying direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a drying device that dries a medium on which an image is formed with ink while transporting the medium. [Background technology]

[0002] An image forming system including an inkjet image forming apparatus is provided with a drying device that dries an image (ink) formed on a medium. The drying device includes a blower fan that takes in outside air and blows it toward the medium, as described in Patent Document 1, for example. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-134477 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the blower fan of the drying device in Patent Document 1 blows air from a direction almost perpendicular to the medium. In this case, if the medium is exposed to a strong wind, the ink may flow and image quality may deteriorate. Also, if the air blown onto the medium flows upstream or downstream in the medium transport direction, the leading edge of the following medium may curl up, or the trailing edge of the preceding medium may curl up, causing medium transport problems.

[0005] SUMMARY OF THE PRESENT DISCLOSURE In consideration of the above circumstances, an object of the present invention is to provide a drying device that dries a medium while stably transporting the medium. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the drying device of the present invention is characterized by comprising a conveying device that conveys a medium on which an image has been formed along a predetermined conveying direction, an air blowing device that dries the medium by blowing air toward the medium from above the medium conveyed by the conveying device, and an exhaust device that takes in air above the medium from both sides of the conveying device in the width direction of the medium that intersects the conveying direction and exhausts it.

[0007] In the present invention, the exhaust device may include ducts disposed on both sides of the transport device in the width direction, and may take in air above the medium via the ducts.

[0008] In the present invention, the conveying device may include an endless conveying belt having a conveying surface that supports the medium and having a large number of through holes, a conveying plate having a large number of through holes that contacts the surface of the conveying belt opposite the conveying surface and supports the conveying belt, and a suction device that creates negative pressure between the through holes of the conveying belt and the through holes of the conveying plate to attract the medium to the conveying surface, and the conveying plate may be formed so that the force attracting the medium to the conveying surface is greater upstream of the air blower in the conveying direction than downstream of the air blower.

[0009] In the present invention, the conveying device may include an endless conveying belt having a conveying surface that supports the medium and having a large number of through holes, a conveying plate having a large number of through holes that contacts the side of the conveying belt opposite the conveying surface and supports the conveying belt, and a suction device that creates negative pressure between the through holes of the conveying belt and the through holes of the conveying plate to attract the medium to the conveying surface, and the conveying plate may be formed so that the force attracting the medium to the conveying surface is greater at the center side in the width direction than at both ends. Effect of the Invention

[0010] According to the present invention, since an exhaust device is provided that takes in air above the medium from both sides of the transport device in the width direction and exhausts it, it is possible to reduce the amount of air blown from the blower device above the transport device and flowing upstream and downstream in the transport direction, thereby suppressing transport problems such as the leading edge of the following medium curling up or the trailing edge of the preceding medium curling up. [Brief description of the drawings]

[0011] [Figure 1] 1 is a front view showing a drying device according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view of a drying device (with a blower omitted) according to an embodiment of the present invention, as viewed from above. [Figure 3A] FIG. 2 is a plan view illustrating the flow of air in the drying device according to the embodiment of the present invention. [Figure 3B] FIG. 2 is a cross-sectional perspective view illustrating the flow of air in the drying device according to one embodiment of the present invention. [Figure 4A] FIG. 2 is a perspective view showing a first modified example of a conveying plate in a drying device according to an embodiment of the present invention. [Figure 4B] FIG. 11 is a perspective view showing a second modified example of the conveying plate in the drying device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, a drying device according to an embodiment of the present invention will be described with reference to the drawings.

[0013] First, the overall configuration of the drying device 1 will be described with reference to Fig. 1. Fig. 1 is a front view showing the inside of the drying device 1. Fr, Rr, L, and R shown in each drawing indicate the front side, rear side, left side, and right side of the drying device 1, respectively.

[0014] The drying device 1 includes a conveying device 3 that conveys a medium on which an image is formed by an inkjet method along a conveying direction X (direction from right to left in FIG. 1), an air blower 5 that dries the medium (cut sheets, long sheets, etc.) conveyed by the conveying device 3, and an exhaust device 7 that exhausts the space above the conveying device 3.

[0015] First, a description will be given of the conveying device 3. The conveying device 3 includes a conveying belt 11 that conveys the medium, a conveying plate 13 that supports the conveying belt 11, and a suction device 15 that attracts the medium to the conveying belt 11.

[0016] The conveyor belt 11 is an endless belt, and has many through holes formed on the entire surface thereof, penetrating in the thickness direction. The conveyor belt 11 is wound around a drive roller 17 and a driven roller 19. The drive roller 17 is driven to rotate by a motor (not shown), causing the conveyor belt 11 to circulate in a counterclockwise direction in FIG. 1. The outer surface of the conveyor belt 11 along the upper track becomes the conveying surface along which the medium is conveyed.

[0017] The conveying plate 13 contacts the inner peripheral surface (the surface behind the conveying surface) of the conveying belt 11 running on the upper track to support the conveying belt 11. When the conveying belt 11 runs, the inner peripheral surface of the conveying belt 11 slides along the upper surface of the conveying plate 13. The conveying plate 13 has a large number of through holes formed all over the surface, penetrating in the thickness direction.

[0018] The suction device 15 is disposed in a hollow portion of the conveyor belt 11. When the suction device 15 is driven, air is sucked in through the through holes of the conveyor belt 11 and the through holes of the conveyor plate 13, and the medium is attracted to the conveying surface of the conveyor belt 11.

[0019] Next, the blower 5 will be described. In this example, two blower devices 5 are arranged side by side in the conveying direction X above the conveying device 3. In detail, the two blower devices 5 are arranged above the downstream side of the conveying device 3 in the conveying direction X. A predetermined space is provided between the two blower devices 5 and the conveying surface of the conveyor belt 11 of the conveying device 3.

[0020] Each blower device 5 has a box-shaped casing 21 with an open bottom. Two blowing fans 23 are provided on the top surface of the casing 21. The four fans 23 send air into the inside of the casing 21. A heat source 25 is provided inside the casing 21. The heat source 25 heats the air inside the casing 21. The air sent into the casing 21 by the two fans 23 is heated by the heat source 25, and the heated air is blown downward, thereby drying the medium transported on the transport surface of the transport belt 11 of the transport device 3.

[0021] Next, the exhaust device 7 will be described with reference to Fig. 2 and also Fig. 3A and Fig. 3B. Fig. 2 is a perspective view of the drying device 1 (without the blower 5) as seen from above. Fig. 3A and Fig. 3B are diagrams for explaining the flow of air in the exhaust device 7.

[0022] 1 and 2, the exhaust device 7 is disposed above the conveying device 3 and downstream of the two blowers 5. The exhaust device 7 has two intake ducts 31 disposed on both sides of the conveying device 3 in the width direction Y of the medium perpendicular to the conveying direction X, a junction duct 33 where the two intake ducts 31 join together, an exhaust duct 35 that connects the junction duct 33 with the outside, and a crossflow fan 37 as an exhaust fan disposed between the junction duct 33 and the exhaust duct 35.

[0023] As shown in FIG. 2, the two intake ducts 31 are disposed along the conveying direction X on both sides of the upper track of the conveyor belt 11. The length of the intake duct 31 along the conveying direction X is approximately equal to the length of the blower 5. Two intake ports 31a along the conveying direction X are formed on the surface of each intake duct 31 facing the space above the conveyor belt 11. As shown in FIG. 3A, an exhaust port 31b is formed on the end of each intake duct 31 on the downstream side in the conveying direction X. The intake port 33a of the junction duct 33 is connected to the exhaust ports 31b of the two intake ducts 31.

[0024] 3B, an exhaust port 33b is formed on the upper surface of the junction duct 33. A downward-facing suction port 37a of a cross-flow fan 37 is connected to the exhaust port 33b of the junction duct 33. An outlet 37b of the cross-flow fan 37 opens downstream in the transport direction X and is connected to an intake port 35a of the exhaust duct 35. The exhaust duct 35 extends upward while curving. An exhaust port 35b of the exhaust duct 35 opens upward.

[0025] When the cross-flow fan 37 is driven, air is taken in through the intake ports 31a of the two intake ducts 31, and the taken in air is exhausted from the two intake ducts 31 to the outside through the junction duct 33 and the exhaust duct 35.

[0026] The drying operation of the drying device 1 having the above configuration will be described with reference to Fig. 1, Fig. 3A, and Fig. 3B. In the conveying device 3, the driving roller 17 is driven to rotate and the conveying belt 11 runs. Thereafter, the medium on which an image is formed by the inkjet method is conveyed to the conveying surface of the conveying belt 11. In addition, the suction device 15 is driven. As a result, air is taken in from the through holes of the conveying belt 11 and the through holes of the conveying plate 13 as described above, and a negative pressure is created above the conveying surface of the conveying belt 11. Then, the medium is attracted to the conveying surface. In this way, the medium is conveyed along the conveying direction X while being attracted to the conveying surface of the conveying belt 11.

[0027] Furthermore, each air blowing device 5 is driven, and the air sent into the casing 21 by the two fans 23 is heated by the heat source 25, and the heated air is blown downward. The heated air is blown onto the medium transported by the transport belt 11 of the transport device 3, and dries the medium (ink).

[0028] Furthermore, the air blown downward in this manner hits the conveyor belt 11 or the medium, passes through the space between the conveyor belt 11 and the blower 5 (the space above the medium), and flows upstream or downstream in the conveying direction X (see the arrows in Figure 1).

[0029] Furthermore, the exhaust fan 37 of the exhaust device 7 is driven. Then, as shown by the arrows in Fig. 3A, air in the space above the conveyor belt 11 is sucked in through the intake ports 31a of the two intake ducts 31. The sucked air flows downstream through the two intake ducts 31 toward the junction duct 33. Then, as shown by the arrows in Fig. 3B, the sucked air rises in the junction duct 33 and is exhausted to the outside through the exhaust duct 35.

[0030] As is clear from the above description, according to the drying device 1 of the present invention, air in the space above the conveyor belt 11 is sucked into the two intake ducts 31 along the width direction Y. This makes it possible to reduce the amount of air (indicated by the arrows in FIG. 1) that is blown from the blower device 5 into the space above the conveyor belt 11 and flows upstream and downstream in the conveying direction X. This makes it possible to suppress poor media conveyance, such as the leading edge of a subsequent medium being curled up or the trailing edge of a preceding medium being curled up.

[0031] Next, a modified example of the drying device 1 of the present invention will be described with reference to Figures 4A and 4B. Figures 4A and 4B are perspective views that typically show the conveying plate 13 of the conveying device 3.

[0032] 4A, a part A of the transport plate 13 upstream of the blower device 5 in the transport direction X is formed to have a greater force for attracting the medium. Specifically, by adjusting the diameter and number of through holes formed in the transport plate 13, the force for attracting the medium can be made greater than that of other parts.

[0033] As described above, the leading edge of the following medium may be curled up by the air blown from the blower 5 into the space above the conveyor belt 11 and flowing upstream in the conveying direction X. Therefore, by increasing the force attracting the medium to the conveyor belt 11 downstream of the blower 5, it is possible to more reliably prevent the medium from curling up. Note that a portion of the conveying plate 13 downstream of the blower 5 in the conveying direction X may also be formed to have a greater force attracting the medium.

[0034] 4B, the center portion A of the transport plate 13 in the width direction Y is formed to have a greater force for attracting the medium. Specifically, as described above, by adjusting the diameter and number of the through holes, the force for attracting the medium can be made greater than that of other portions.

[0035] When the medium is small in size, the leading edge is particularly likely to curl up due to the air blown from the blower 5 into the space above the conveyor belt 11 and flowing upstream in the conveying direction X. Therefore, by increasing the force attracting the medium to the conveyor belt 11 at the center A in the width direction Y, small-sized media can be reliably attracted to the conveyor belt 11 and conveyed. Also, for media other than small sizes, by increasing the force attracting the center A to the conveyor belt 11, the effect of suppressing the curling up of the medium can be obtained.

[0036] Although the present invention has been described with respect to a specific embodiment, the present invention is not limited to the above embodiment. The above embodiment may be variously changed, substituted, or modified without departing from the scope and spirit of the present invention, and the claims include all embodiments that may be included within the scope of the technical idea. [Explanation of symbols]

[0037] 1 Drying device 3. Conveyor 5 Drying equipment 7 Exhaust system 11 Conveyor belt 13 Transport plate 15 Suction device 31 Intake duct

Claims

1. A conveying device that conveys the medium on which the image is formed along a predetermined conveying direction; a blower that blows air toward the medium from above the medium being transported by the transport device to dry the medium; a drying device that is provided with an exhaust device that takes in air above the medium from both sides of the conveying device in a width direction of the medium that intersects with the conveying direction and exhausts it.

2. The drying device according to claim 1 , wherein the exhaust device includes ducts disposed on both sides of the conveying device in the width direction, and takes in air above the medium through the ducts.

3. The conveying device is an endless conveyor belt having a conveying surface for supporting the medium and having a large number of through holes; a conveying plate having a large number of through holes formed therein, the conveying plate being in contact with a surface of the conveying belt opposite to the conveying surface and supporting the conveying belt; a suction device that applies negative pressure to the through holes of the conveyor belt and the through holes of the conveyor plate to attract the medium to the conveyor surface, 2. The drying device according to claim 1, wherein the transport plate is formed so that a force attracting the medium to the transport surface is greater on an upstream side of the air blower in the transport direction than on a downstream side of the air blower.

4. The conveying device is an endless conveyor belt having a conveying surface for supporting the medium and having a large number of through holes; a conveying plate having a large number of through holes formed therein, the conveying plate being in contact with a surface of the conveying belt opposite to the conveying surface and supporting the conveying belt; a suction device that applies negative pressure to the through holes of the conveyor belt and the through holes of the conveyor plate to attract the medium to the conveyor surface, 2 . The drying device according to claim 1 , wherein the transport plate is formed so that a force attracting the medium to the transport surface is greater at a center side in the width direction than at both end sides.

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