Dryer

Abstract

To provide a dryer which can change intensity of an infrared ray radiated to a recording medium according to a state of the recording medium.SOLUTION: A dryer includes: a transport member which supports a recording medium M and transports the recording medium M in a predetermined transport direction; and a heating device which heats the recording medium M transported by the transport member under a high temperature environment. The heating device includes: a heater 41 which radiates an infrared ray; a reflection plate 43 which reflects the infrared ray radiated from the heater 41 toward the recording medium; and a lifting mechanism which moves up or down the reflection plate 43 relative to the heater 41 to change the number of reflection of the infrared ray.SELECTED DRAWING: Figure 3B

Description

[Technical field]

[0001] The present invention relates to a drying device that dries, while conveying, a recording medium on which an image has been formed by an inkjet method. [Background technology]

[0002] An image forming system including an inkjet image forming apparatus is provided with a drying device that dries an image formed on a recording medium with ink. As described in Patent Document 1, the drying device includes a fan that takes in outside air and blows it onto the recording medium, multiple heaters that emit infrared rays, and multiple reflectors that are provided for each heater and reflect the infrared rays emitted from the heaters and emit them toward the recording medium. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-149329 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in a drying device such as that described in Patent Document 1, the optimal drying degree of the recording medium (ink) varies depending on the type and discharge amount of ink, the type of recording medium, etc. However, since a heater can generally only be switched between an on state and an off state, the intensity of infrared rays irradiated onto the recording medium is always constant. In other words, it is difficult to change the intensity of infrared rays irradiated onto the recording medium from the heater so as to achieve optimal conditions according to the state of the recording medium (ink). For this reason, when the type of ink or recording medium is changed, it may be necessary to replace the heater itself.

[0005] SUMMARY OF THE PRESENT EMBODIMENT In consideration of the above circumstances, an object of the present invention is to provide a drying device capable of changing the intensity of infrared rays irradiated onto a recording medium in accordance with the state of the recording medium. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the drying device of the present invention is a drying device that dries a recording medium on which an image is formed while transporting it, and is characterized in that it comprises a transport member that supports the recording medium and transports it in a predetermined transport direction, and a heating device that heats the recording medium transported by the transport member in a high-temperature environment, and the heating device comprises a heater that radiates infrared rays, a reflecting plate that reflects the infrared rays radiated from the heater toward the recording medium, and a lifting mechanism that raises and lowers the reflecting plate relative to the heater to change the number of times the infrared rays are reflected.

[0007] In the present invention, the lifting mechanism may be configured to lift the reflector to reduce the number of reflections when it is desired to increase the intensity of the infrared rays irradiated onto the recording medium.

[0008] In the present invention, a plurality of the reflecting plates may be provided, and the lifting mechanism may lift and lower the plurality of reflecting plates simultaneously.

[0009] In the present invention, a plurality of the reflecting plates may be provided, and the lifting mechanism may lift and lower the plurality of reflecting plates individually.

[0010] In the present invention, the lifting mechanism may be a rack and pinion mechanism. Effect of the Invention

[0011] According to the present invention, the illuminance of the infrared light irradiated onto the recording medium can be changed by changing the number of times the infrared light is reflected by the reflector by raising and lowering the reflector. [Brief description of the drawings]

[0012] [Figure 1] 1 is a front view showing the inside of a drying device according to an embodiment of the present invention. [Diagram 2]5 is a diagram showing a mechanism for lifting and lowering a reflecting plate in the drying device according to the embodiment of the present invention. FIG. [Figure 3A] FIG. 2 is a front view showing a typical state of infrared rays reflected by a reflecting plate (when lowered) in the drying device according to one embodiment of the present invention. [Figure 3B] FIG. 2 is a front view showing a typical state of infrared rays reflected by a reflecting plate (when raised) in the drying device according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, a drying device according to an embodiment of the present invention will be described with reference to the drawings.

[0014] 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.

[0015] The drying device 1 includes a transport device 3 that transports a recording medium on which an image is formed by an inkjet method, and a heating device 5 that dries the ink on the recording medium transported by the transport device 3 in a high-temperature environment.

[0016] First, a description will be given of the conveying device 3. The conveying device 3 includes a conveying belt 11 that conveys the recording medium along a conveying direction X from right to left in Fig. 1, a conveying plate 13 that supports the conveying belt 11, a suction device 15 that attracts the recording medium to the conveying belt 11, and front and rear side plates 17 that support these.

[0017] First, the front and rear side plates 17 will be described. The front and rear side plates 17 are plate-shaped members that are long in the width direction (the direction intersecting the conveying direction X, the left-right direction) and are arranged with a gap in between in the front-rear direction. Two chambers 19 aligned in the conveying direction X are formed in the lower part of the space between the front and rear side plates 17.

[0018] A driving roller 21 and a driven roller 23 are supported between the front and rear side plates 17. The driving roller 21 is rotatably supported at the downstream end (left end) of the front and rear side plates 17 in the conveying direction X. The driven roller 23 is rotatably supported at the upstream end (right end) of the front and rear side plates 17 in the conveying direction. A drive shaft of the driving roller 21 is connected to a motor (not shown).

[0019] Next, the conveyor belt 11 will be described. The conveyor belt 11 is an endless belt, and a large number of through holes penetrating in the thickness direction are formed on the entire surface. The conveyor belt 11 is wound around a driving roller 21 and a driven roller 23. The driving roller 21 is driven by a motor to rotate, and the conveyor belt 11 circulates and runs in a counterclockwise direction in FIG. 1. The outer surface of the conveyor belt 11 along the upper track becomes the conveying surface on which the recording medium is conveyed. Thus, the conveyor belt 11 is an example of a conveying member for conveying a recording medium in the present invention.

[0020] Next, the conveying plate 13 will be described. The conveying plate 13 is supported by front and rear side plates 17 so as to come into contact with the inner peripheral surface (the surface behind the conveying surface) of the conveying belt 11 running on the upper track. 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. A large number of through holes penetrating the conveying plate 13 in the thickness direction are formed on the entire surface.

[0021] Next, the suction device 15 will be described. The suction device 15 is disposed in each of two chambers 19 formed between the front and rear side plates 17. When the suction device 15 is driven, air is sucked in through holes in the conveyor belt 11 and the conveyor plate 13. As a result, the recording medium on the conveyor surface of the conveyor belt 11 is attracted to the conveyor belt 11.

[0022] Next, a description will be given of the heating device 5. The heating device 5 includes two heater units 31, two fans 33 provided in each heater unit 31, and a housing 35 in which these are housed.

[0023] The housing 35 is formed in a box shape with an open bottom. The opening on the bottom is covered with a protective net 37.

[0024] The two heater units 31 are arranged side by side in the conveying direction X in the hollow portion of the housing 35. Each heater unit 31 has a plurality of infrared heaters 41 arranged side by side in the conveying direction X, and a reflector 43 that reflects infrared rays emitted from each infrared heater 41. The infrared heater 41 radiates infrared rays mainly from the lower half. The reflector 43 has a box shape with an opening at the bottom, and has a top plate, left and right side plates, and front and rear side plates. The inner surface of each plate is mirror-finished. The reflector 43 is arranged to surround the heater 41. The infrared rays emitted from the heater 41 are reflected multiple times mainly by the inner surfaces of the left and right side plates and the front and rear side plates of the reflector 43, and are irradiated downward.

[0025] The reflecting plates 43 are supported so as to be movable up and down by a lifting mechanism 51 made of a rack and pinion mechanism. The lifting mechanism 51 will be described with reference to Fig. 2. Fig. 2 is a diagram showing the lifting mechanism 51.

[0026] The lifting mechanism 51 includes rack gears 53 (53F, 53R) fixed to the multiple reflectors 43, and a pinion gear 55 rotatably supported on the rear side plate 35R of the housing 35. Both front and rear ends of the multiple reflectors 43 are suspended and supported by front and rear support plates 59F, 59R, respectively. The front and rear support plates 59F, 59R are fixed to the front and rear rack gears 53F, 53R. The front and rear rack gears 53F, 53R are supported on the inner surfaces of the front and rear side plates 35F, 35R of the housing 35 so as to be movable in the up and down direction.

[0027] The pinion gear 55 is rotatably supported on the inner surface of the rear plate 35R and meshes with the rear rack gear 53R. A drive motor 61 is supported on the rear surface of the rear plate 35R. The drive shaft of the drive motor 61 passes through the rear plate 35R. A drive gear 63 is fixed to the tip of the drive shaft protruding from the rear plate 35R. The drive gear 63 meshes with the pinion gear 55.

[0028] Furthermore, a connection member 65 for synchronously moving the front and rear rack gears 53F, 53R is disposed between the front and rear side plates 35F, 35R. The connection member 65 has a rotating shaft 67 and front and rear gears 69F, 69R fixed to both ends of the rotating shaft 67. Both ends of the rotating shaft 67 are rotatably supported by the front and rear side plates 35F, 35R. The front and rear gears 69F, 69R mesh with the front and rear rack gears 53F, 53R, respectively.

[0029] When the drive motor 61 is driven to rotate, the pinion gear 55 rotates in conjunction with the rotation of the drive gear 63. As a result, the rear rack gear 53R meshing with the pinion gear 55 rises and falls. As the rear rack gear 53R rises and falls, the rear gear 69R of the connection member 65 rotates. Then, the front gear 69F also rotates together with the rear gear 69R, and the front rack gear 53F meshing with the front gear 69F rises and falls in synchronization with the rear rack gear 53R. As a result, the multiple reflectors 43 supported by the support plates 59F, 59R rise and fall together.

[0030] The plurality of reflectors 43 are raised and lowered between a lower position and an upper position by the lifting mechanism 51. At the lower position, the heater 41 is located at approximately the center of the height of the reflector 43, and the length of the reflector 43 (front, rear, left and right side panels) below the heater 41 is longer (described later with reference to FIG. 3A). At the upper position, the heater 41 is located slightly below the center of the height of the reflector 43, and the length of the reflector 43 (front, rear, left and right side panels) below the heater 41 is shorter (described later with reference to FIG. 3B). That is, as the reflector 43 is raised and lowered, the number of times that the infrared rays are reflected by the side panels of the reflector 43 changes (described in detail later).

[0031] 1 again, two fans 33 are provided on the upper surface of each heater unit 31. Fans 33 take in air inside housing 35 and blow it out downward. The air blown out downward is heated as it passes through heater unit 31, generating downward hot air.

[0032] The heating device 5 is disposed above the conveying surface of the conveyor belt 11 of the conveying device 3 with a predetermined distance therebetween.

[0033] The drying operation of the drying device 1 having the above configuration will be described with reference to Figures 3A and 3B. Figures 3A and 3B are schematic diagrams showing reflection of infrared rays by a reflecting plate 43.

[0034] In the conveying device 3, the driving roller 21 is driven to rotate and the conveying belt 11 runs. Thereafter, the recording 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 sucked into 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 recording medium is attracted to the conveying surface. In this way, the recording medium is conveyed along the conveying direction X while being attracted to the conveying surface.

[0035] Furthermore, the heater unit 31 and the fan 33 of the heating device 5 are driven. The reflector 43 of the heater unit 31 is lowered to the lower position by the lifting mechanism 51. As described above, the infrared rays emitted from the infrared heater 41 are reflected by the reflector 43 and irradiated downward. Specifically, as shown in FIG. 3A, the infrared rays R radiated from a predetermined position of the infrared heater 41 are reflected by the left side plate, then the right side plate, and then the left side plate, and are irradiated toward the recording medium. Thus, in this example, the number of reflections is three.

[0036] In addition, the air blown downward by the fan 33 passes through the heater unit 31 and is heated to generate downward hot air. In this way, the heating device 5 blows out heated air (hot air) downward. The recording medium (ink) transported to the transport surface of the transport belt 11 is dried by such infrared rays and hot air.

[0037] When the amount of ink ejected onto the recording medium is greater than the standard amount, or when the recording medium is one to which ink is difficult to adhere, it is necessary to increase the illuminance of the infrared light irradiated onto the recording medium, and to make the strength of the ink drying (referred to as the drying intensity) stronger than under standard conditions.

[0038] In this case, as described above, the pinion gear 55 of the lifting mechanism 51 is rotated to raise the rack gears 53F, 53R, and the reflector 43 is raised to the upper position together with the support plates 59F, 59R. Then, as shown in Fig. 3B, the infrared rays R emitted from a predetermined position of the infrared heater 41 are reflected by the left side plate, then by the right side plate, and then are irradiated toward the recording medium. In this example, the number of reflections is two. This is fewer than the case shown in Fig. 3A (three reflections when the reflector 43 is lowered to the lower position).

[0039] Each time the infrared rays are reflected by the reflector 43, they are diffused or absorbed by the reflector 43, and their intensity weakens. In other words, the more times the rays are reflected, the weaker their intensity becomes. Therefore, the amount of infrared rays diffused or absorbed by the reflector is less than in the case shown in Fig. 3A, and the illuminance of the infrared rays irradiated onto the recording medium becomes stronger. Therefore, the recording medium can be dried with a drying intensity stronger than that in the standard state.

[0040] As is clear from the above description, according to the drying device 1 of the present invention, the intensity at which the recording medium (ink) is dried can be changed by raising and lowering the reflecting plate 43. Specifically, when it is desired to increase the illuminance of the infrared light irradiated onto the recording medium, the reflecting plate 43 is raised to reduce the number of times the infrared light is reflected. Therefore, the recording medium can be dried at an intensity suitable for the recording medium without replacing the heater 41.

[0041] In addition, since the lifting mechanism 51 for lifting and lowering the reflector 43 is configured as a rack-and-pinion mechanism, the reflector 43 can be accurately lifted and lowered to the upper and lower positions with a simple configuration. The positions of the reflector 43 are not limited to the upper and lower positions, and the reflector 43 may be lifted and lowered to heights other than these positions (heights). In addition, the lifting mechanism 51 is not limited to a rack-and-pinion mechanism. For example, the reflector 43 may be lifted and lowered via the support plates 59F and 59R using a solenoid. Alternatively, the reflector 43 may be lifted and lowered by suspending the support plates 59F and 59R with a wire and winding or unwinding the wire with a winding roller.

[0042] The determination as to whether or not the drying intensity of the recording medium needs to be increased is made by the user or a serviceman. In this case, for example, a selection button is provided on the operation panel of the drying device 1, and when it is necessary to increase the drying intensity, pressing the selection button drives the motor 61 to raise the reflector 43 to the upper position.

[0043] In the above embodiment, the configuration in which the multiple reflectors 43 are raised and lowered simultaneously has been described, but the multiple reflectors 43 may be raised and lowered individually. For example, on the upstream side of the transport direction X, the reflector 43 is lowered to a lower position to weaken the illuminance of the infrared light irradiated to the recording medium. On the other hand, on the downstream side of the transport direction X, the reflector 43 is raised to an upper position to strengthen the illuminance of the infrared light irradiated to the recording medium. Alternatively, the height of the reflector 43 is gradually increased from the upstream side to the downstream side of the transport direction X. As a result, for example, when ink that dries easily is used, the illuminance of the infrared light irradiated to the recording medium is weakened on the upstream side of the transport direction X, so that the ink can be prevented from drying suddenly and the ink can be dried gradually.

[0044] 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]

[0045] 1 Drying device 5 Heating device 11 Transport member 41 Heater 43 Reflector 51 Lifting mechanism

Claims

1. A drying device that dries a recording medium on which an image is formed while conveying the recording medium, a conveying member that supports the recording medium and conveys it in a predetermined conveying direction; a heating device that heats the recording medium conveyed by the conveying member in a high-temperature environment, The heating device includes: A heater that emits infrared rays; a reflector that reflects infrared rays radiated from the heater toward the recording medium; a lifting mechanism for raising and lowering the reflecting plate relative to the heater to change the number of times the infrared ray is reflected.

2. The lifting mechanism includes:

2. The drying device according to claim 1, wherein when it is desired to increase the intensity of the infrared rays irradiated onto the recording medium, the reflecting plate is raised to reduce the number of reflections.

3. A plurality of the reflectors are provided, 2. The drying apparatus according to claim 1, wherein the lifting mechanism lifts and lowers the plurality of reflecting plates simultaneously.

4. A plurality of the reflectors are provided, 2. The drying device according to claim 1, wherein the lifting mechanism lifts and lowers the plurality of reflecting plates individually.

5. 2. The drying apparatus according to claim 1, wherein the lifting mechanism is a rack and pinion mechanism.

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