Dryer

Abstract

To provide a dryer capable of ensuring cutting-off between a heating space below a heater unit and a space in a casing.SOLUTION: This dryer for conveying a medium in which an image is formed and drying it under a high-temperature environment comprises: a conveyance unit that supports and conveys the medium in a prescribed conveying direction; a heater unit 21 that is disposed above the conveyance unit to spray high-temperature air to the conveyed medium; a casing 23 that stores the heater unit 21; a lifting mechanism provided in the casing 23 to support the heater unit 21 so as to be liftable; and a closing member 51A that abuts against the heater unit 21 during lowering of the heater unit 21 and cuts off a heating space S2 below the heater unit 21 and a space S1 in the casing from each other. The closing member 51A can be lifted within a prescribed range along with lifting of the heater unit 21.SELECTED DRAWING: Figure 5B

Description

[Technical field]

[0001] The present invention relates to a drying device that dries a recording medium on which an image has been formed in a high-temperature environment while conveying the recording medium. [Background technology]

[0002] An image forming system including an inkjet type image forming apparatus is provided with a drying device that dries an image formed with ink on a recording medium. The drying device includes a transport unit that transports the medium on which the image has been formed by the inkjet method, and a heater unit that dries the medium transported by the transport unit.

[0003] The heater unit generally has multiple infrared heaters, a reflector that reflects infrared rays emitted from each infrared heater, and a fan. The infrared heaters and the reflector are housed in a casing that is open at the bottom. The infrared rays emitted from the infrared heaters 43 are reflected by the reflector and irradiated downward. The fan is supported on the top surface of the casing and blows the air it takes in downward.

[0004] In such a drying device, when the recording medium being transported by the transport unit becomes jammed, as described in Patent Document 1, the driving of the heating section (corresponding to the heater unit) of the drying device is stopped. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2022-148189 A Summary of the Invention [Problem to be solved by the invention]

[0006] In some cases, the heater unit is provided so as to be capable of being raised and lowered in order to clear a paper jam in the recording medium being transported by the transport unit. In this case, the heater unit is housed in a casing with an open bottom, and is raised and lowered by a lifting mechanism supported by the casing. When clearing a paper jam, the heater unit is raised by the lifting mechanism, and a space is formed between the heater unit and the transport unit in order to remove the jammed paper.

[0007] Below the heater unit is a heating space where the temperature is rising due to heated air. When the heated air in this heating space enters the inside of the casing, the inside of the casing is also heated. This causes the components that make up the lifting mechanism supported by the casing to be exposed to high temperatures, which can damage components with low heat resistance.

[0008] For this reason, a measure is sometimes taken to isolate the heating space below the heater unit from the space inside the casing by providing a sponge that comes into contact with the heater unit when it descends. However, if the position of the heater unit varies when it descends or if the sponge becomes deformed, the effect of isolating the space is reduced.

[0009] SUMMARY OF THE PRESENT DISCLOSURE In consideration of the above circumstances, an object of the present invention is to provide a drying device that can reliably isolate the heating space below the heater unit from the space inside the casing. [Means for solving the problem]

[0010] In order to achieve the above-mentioned object, the drying device of the present invention is a drying device that dries a medium on which an image is formed in a high-temperature environment while transporting the medium, and is equipped with a transport unit that supports the medium and transports it in a predetermined transport direction, a heater unit that is arranged above the transport unit and blows high-temperature air onto the medium being transported, a casing that houses the heater unit, a lifting mechanism that is provided in the casing and supports the heater unit so that it can be raised and lowered, and a closing member that abuts against the heater unit when the heater unit is lowered, thereby blocking off the heating space below the heater unit and the internal space of the casing, and is characterized in that the closing member can be raised and lowered within a predetermined range in accordance with the raising and lowering of the heater unit.

[0011] In the present invention, the closing member may be supported by the casing so as to be movable in the up and down direction by a biasing member.

[0012] In the present invention, a plurality of the heater units may be provided adjacent to each other, and the closing member may be disposed between the heater unit and the casing and between adjacent heater units. Effect of the Invention

[0013] According to the present invention, the interior space of the casing is blocked off from the heating space by the closing member, and the interior of the casing is not heated, so that the lifting mechanism supported by the casing is less susceptible to the effects of heating. [Brief description of the drawings]

[0014] [Figure 1] 1 is a front view showing a schematic view of the inside of a drying device according to an embodiment of the present invention; [Diagram 2] 1 is a perspective view showing a transport unit (transport belt is not shown) in a drying device according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a perspective view showing a closing member in the drying device according to one embodiment of the present invention. [Figure 4] FIG. 2 is a front view showing a schematic view of a lifting mechanism in the drying device according to one embodiment of the present invention. [Figure 5A] FIG. 2 is a front view showing a heater unit during drying in the drying device according to the embodiment of the present invention. [Figure 5B] FIG. 5B is an enlarged view of a part (closing member) of FIG. 5A. [Figure 6A] FIG. 2 is a front view showing a heater unit in a standby state in the drying device according to the embodiment of the present invention. [Figure 6B] FIG. 6B is an enlarged view of a part (closing member) of FIG. 6A. [Figure 7A] 1 is a front view showing a heater unit abutting against a closing member when lowered in a drying device according to an embodiment of the present invention. FIG. [Figure 7B] FIG. 7B is an enlarged view of a part (closing member) of FIG. 7A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, a drying device according to an embodiment of the present invention will be described with reference to the drawings.

[0016] The overall configuration of the drying device 1 will be described with reference to Fig. 1. Fig. 1 is a front view that typically illustrates the inside of the drying device 1. Fr, Rr, L, and R in each drawing indicate the front side, rear side, left side, and right side of the drying device 1, respectively.

[0017] The drying device 1 includes a transport unit 3 that transports a medium (a cut sheet, a long sheet, etc.) on which an image has been formed by an inkjet method along a transport direction X1 (direction from right to left in Figure 1), and a heating unit 5 that dries the medium transported by the transport unit 3.

[0018] First, the transport unit 3 will be described with reference to Fig. 1 and Fig. 2. Fig. 2 is a perspective view showing the transport unit 3 (the transport belt 11 is not shown). As shown in Fig. 1 and Fig. 2, the transport unit 3 includes the transport belt 11 that transports the medium, a transport plate 13 that supports the transport belt 11, and a suction device 15 that attracts the medium to the transport belt 11.

[0019] The conveyor belt 11 is an endless belt, and has many through holes formed on its entire surface 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 and run counterclockwise in FIG. 1. The outer surface of the conveyor belt 11 along the upper track becomes the conveying surface along which the recording medium is conveyed.

[0020] The conveying plate 13 will now be described. The conveying plate 13 comes into contact with the inner peripheral surface (the surface behind the conveying surface) of the conveying belt 11 running on the upper track, and supports 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 it in the thickness direction.

[0021] 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.

[0022] Next, the heating unit 5 will be described with reference to Fig. 1 and Figs. 3 to 7B. Fig. 3 is a perspective view showing the closing member, Fig. 4 is a front view showing the lifting mechanism, and Figs. 5A to 7B are front views showing the heater unit.

[0023] 1, the heating unit 5 is disposed above a portion slightly downstream of the center in the conveying direction X1 of the conveying unit 3. The heating unit 5 includes two heater units 21, a casing 23 that houses the two heater units 21, and a lifting mechanism 25 (see FIG. 4) that supports the two heater units 21 on the casing 23 so that they can be raised and lowered.

[0024] First, the heater unit 21 will be described with reference to Figures 1, 5A, 6 and 7A. The heater unit 21 has a plurality of infrared heaters 31, a reflector 33 that reflects infrared rays radiated from each of the infrared heaters 31, two fans 35, and a heater casing 37 that supports these.

[0025] The heater casing 37 is in the shape of a box with an open bottom, and has left and right side panels facing the conveying direction X1, front and rear side panels facing the width direction X2 intersecting the conveying direction X1, and a top panel. The left and right side panels have lower edges that are bent inward at approximately right angles.

[0026] The multiple infrared heaters 31 and the reflecting plate 33 are arranged side by side in the conveying direction X1 and housed in a heater casing 37. Infrared rays emitted from the infrared heaters 31 are reflected by the reflecting plate 33 and irradiated downward.

[0027] The two fans 35 are provided on the upper surface of the top plate of the heater casing 37. The fans 35 take in air from outside the heater casing 37 and blow it out toward the inside of the heater casing 37 below.

[0028] The two heater units 21 are arranged side by side in the transport direction X1 with a predetermined gap between them.

[0029] Next, the casing 23 will be described. As shown in Fig. 1, the casing 23 is formed in a box shape with an open bottom, and has an internal space S1 capable of accommodating two heater units 21. Between the bottom opening surface 23a of the casing 23 and the conveying surface of the conveyor belt 11 of the conveying unit 3, a heating space S2 of a predetermined height is formed.

[0030] The casing 23 has left and right side plates 41L, 41R facing each other in the conveying direction X1, front and rear side plates 41Fr, 41Rr facing each other in the width direction X2, and a top plate 41U. As shown in Fig. 3, front and rear beam members 45Fr, 45Rr are suspended between the lower ends of the left and right side plates 41L, 41R. A vertical partition plate 47 is suspended between the centers of the front and rear beam members 45Fr, 45Rr. The partition plate 47 corresponds to the gap between the heater units 21 (see Fig. 1) lined up in the conveying direction X1.

[0031] 3, four closing members 51A, 51B, 51C, 51D (collectively referred to as closing members 51) are supported on the casing 23. The closing member 51 is an L-shaped member when viewed from the front side, with a length equivalent to the distance between the front and rear beam members 45Fr, 45Rr of the casing 23, and has a vertical piece 53 and a horizontal piece 55 bent at a substantially right angle from the lower end of the vertical piece 53. The four closing members 51A, 51B, 51C, 51D are supported movably in the up and down direction by the lower end of the inner surface of the left side plate 41L, the lower ends of both sides of the partition plate 47, and the lower end of the inner surface of the right side plate 41R, respectively.

[0032] In detail, the vertical pieces 53 of the four closing members 51A, 51B, 51C, and 51D are supported so as to be movable in the vertical direction along the lower end of the inner surface of the left side plate 41L, the lower ends of both sides of the partition plate 47, and the lower end of the inner surface of the right side plate 41R. As a result, the horizontal piece 55 of the closing member 51A supported by the left side plate 41L and the horizontal piece 55 of the closing member 51B supported by the downstream side surface of the partition plate 47 extend in directions opposite to each other. In addition, the horizontal piece 55 of the closing member 51C supported by the upstream side surface of the partition plate 47 and the horizontal piece 55 of the closing member 51D supported by the right side plate 41R extend in directions opposite to each other.

[0033] Each of the four closing members 51 is biased upward by a coil spring 57. The coil portion of the coil spring 57 is accommodated in an opening formed in the left side plate 41L, the partition plate 47, the right side plate 41R, and the closing member 51. The upper end of the coil spring 57 is fixed to the left side plate 41L, the partition plate 47, and the right side plate 41R above the opening. The lower end of the coil spring 57 is fixed to the vertical piece 53 of the closing member 51. When the coil spring 57 is in its natural length, the horizontal piece 55 of the closing member 51 is located above the lower opening surface 23a of the casing 23. The coil spring 57 is an example of a biasing member that supports the closing member 51 on the casing 23 so as to be movable in the vertical direction.

[0034] Next, the lifting mechanism 25 will be described. As described above, the lifting mechanism 25 supports the two heater units 21 on the casing 23 so that they can be raised and lowered. The lifting mechanism 25 raises and lowers the two heater units 21 to a heating position (see FIG. 1) where the lower opening surface 37a (see FIG. 1) of the heater casing 37 is at the same height as the lower opening surface 23a of the casing 23, and a retracted position that is higher than the heating position. In the retracted position, a space is formed between the two heater units 21 and the conveying surface of the conveyor belt 11 in which paper jams can be dealt with.

[0035] As the lifting mechanism 25, for example, a ball screw mechanism can be used. As shown in FIG. 4, the ball screw mechanism has a nut 61 fixed to the front and rear side plates of the heater casing 37 of each heater unit 21, and a screw shaft 63 supported by the casing 23 and screwed into the nut 61. The upper and lower ends of the screw shaft 63 are rotatably supported via bearings on a base plate 65 fixed to the inner surface of the front and rear side plates 41Fr, 41Rr (see FIG. 1) of the heater casing 37. Furthermore, a guide rail 67 with which the nut 61 engages is formed along the up-down direction on the base plate 65. A motor 69 is connected to the upper end of the screw shaft 63. When the motor 69 is driven to rotate, the screw shaft 63 rotates, and the nut 61 moves up and down along the guide rail 67. As a result, the heater unit 21 fixed to the nut 61 moves up and down.

[0036] The drying operation of the drying device 1 having the above configuration will be described. In the transport unit 3, the motor is driven to rotate the drive roller 17, and the transport belt 11 travels in a circular motion. Thereafter, the recording medium on which an image is formed by the inkjet method is transported to the transport surface of the transport belt 11. In addition, the suction device 15 is driven. As a result, air is taken in from the through holes of the transport belt 11 and the through holes of the transport plate 13 as described above, and negative pressure is created above the transport surface of the transport belt 11. Then, the recording medium is attracted to the transport surface. In this way, the recording medium is transported along the transport direction X1 while being attracted to the transport surface.

[0037] As shown in Fig. 5A and Fig. 5B, the two heater units 21 are lowered to the heating position by the lifting mechanism 25 (see Fig. 4). That is, the lower opening surface 37a of the heater casing 37 of the heater unit 21 is located at substantially the same height as the lower opening surface 23a of the casing 23. The heater units 21 are driven to heat the heating space S2. As a result, the image on the recording medium transported on the transport surface of the transport belt 11 is dried.

[0038] Here, the movement of the closing member 51 when the heater unit 21 descends will be described. When the two heater units 21 descend from the retracted position to the heating position, the lower edge of the side plate of the heater casing 37 of the two heater units 21 eventually comes into contact with the horizontal pieces 55 of the four closing members 51 as shown in Figs. 7A and 7B. Furthermore, when the two heater units 21 descend, the horizontal pieces 55 of the four closing members 51 are pressed down by the heater casing 37 as shown in Figs. 5A and 5B, and the four closing members 51 each descend against the biasing force of the coil spring 57 (see the arrows in Fig. 5B). As a result, the gaps between the two heater units 21 and the casing 23 and the gaps between the two heater units 21 are blocked by the horizontal pieces 55 of the four closing members 51. In this way, the heating space S2 and the internal space S1 of the casing 23 are blocked during the drying operation.

[0039] On the other hand, if the recording medium being conveyed by the conveyor belt 11 becomes jammed, the conveyor unit 3 is stopped and the heating unit 5 stops heating. Furthermore, as shown in Fig. 6A, the heating unit 5 is moved to the retreat position by the lifting mechanism 25. As a result, a space is formed between the heating unit 5 and the conveyor belt 11, so that the jammed recording medium can be removed. Note that since the two heater units 21 are separated from the four closing members 51, the four closing members 51 are biased upward by the coil springs 57 as shown in Fig. 6B.

[0040] As is clear from the above description, according to the drying device 1 of the present invention, during the heating operation by the heating unit 5, the internal space S1 of the casing 23 is blocked from the heating space S2 by the closing member 51, so that the internal space S1 of the casing 23 is not heated. Therefore, the components (in this example, nuts, bearings, etc.) constituting the lifting mechanism 25 (in this example, a ball screw mechanism) supported by the casing 23 are not easily affected by the heat.

[0041] In addition, since the closing member 51 can move up and down within a predetermined height (between the height shown in Figs. 7A and 7B and the height shown in Figs. 5A and 5B), even if the heating positions of the two heater units 21 vary in the up and down direction, the closing member 51 and the heater casing 37 come into contact with each other, and the internal space S1 of the casing 23 and the heated space S2 can be blocked off. Furthermore, unlike a sponge, the closing member 51 is not easily deformed, and therefore the blocking function can be maintained.

[0042] As the lifting mechanism 25 for the two heater units 21, a rack and pinion mechanism may be used instead of the ball screw mechanism.

[0043] 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]

[0044] 1 Drying device 3. Transport unit 21 Heater unit 23 Casing 25 Lifting mechanism 51A, 51B, 51C, 51D Closing members 57 Coil spring (biasing member)

Claims

1. A drying device that dries a medium on which an image is formed in a high-temperature environment while conveying the medium, a transport unit that supports the medium and transports it in a predetermined transport direction; a heater unit disposed above the transport unit and configured to blow high-temperature air onto the medium being transported; a casing in which the heater unit is housed; a lifting mechanism provided in the casing and configured to support the heater unit so that the heater unit can be lifted and lowered; a closing member that comes into contact with the heater unit when the heater unit is lowered to isolate a heating space below the heater unit from an internal space of the casing, The drying apparatus according to claim 1, wherein the closing member is capable of ascending and descending within a predetermined range in response to the ascending and descending movement of the heater unit.

2. 2. The drying device according to claim 1, wherein the closing member is supported by the casing so as to be movable in the vertical direction by a biasing member.

3. The heater units are provided adjacent to each other, 2. The drying apparatus according to claim 1, wherein the closing member is disposed between the heater unit and the casing and between adjacent heater units.

Images