JP2014219114A - Dryer and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dryer for sheet that can continue heating even if conveyance of a sheet is stopped, shortens a re-startup time, and protects the sheet in the dryer.SOLUTION: When sheet conveyance is stopped owing to jamming, a dancer roller 10 is moved into a low-temperature space 7, and a continuous sheet P is thereby positioned in the low-temperature space 7. At this time, first shutter parts 17a, 17b close an opening part 19 of a heating space 6 so as to thermally isolate the heating space 6 and low-temperature space 7 from each other. Namely, even when the temperature in the heating space 6 is raised by a heating part 15, heat there of is suppressed from being conducted to the low-temperature space 7. Consequently, the continuous sheet P present in the low-temperature space 7 is not exposed to high temperature by the heating part 15, and thermal damage can be suppressed. Further, the heating in the heating space 6 can be continued so as to eliminate a re-startup time resulting from a temporary stop of heating.

Description

  The present invention relates to a drying apparatus and a recording apparatus, and more particularly to a technique for drying a liquid applied to a sheet by recording or coating.

  Patent Document 1 describes a system in which a plurality of units each composed of a printing or coating mechanism and a drying mechanism are arranged, and a web-like substrate is passed through the plurality of units for printing and subsequent drying. Yes. In a unit that does not perform printing or coating, the loss of the web-like base material finally obtained as a result of printing or the like is minimized by adjusting the length that the web-like base material passes through the drying apparatus. It is suppressed. Specifically, the web-like base material transported and guided by the guide roll in the drying device is changed by changing the transport path of the web-like base material by moving the guide roll, thereby passing through the drying device. It is to adjust the thickness.

JP 2010-14356 A

  By the way, in an apparatus that performs recording or liquid application on a continuous sheet such as a web, it is necessary to stop the conveyance of the continuous sheet due to maintenance of the recording unit or the application unit or occurrence of a jam in the apparatus. In general, when the continuous sheet is stagnated in the drying apparatus due to this conveyance stop, heating is stopped, outside air is taken in, and the like, and the temperature in the apparatus is lowered. However, in such a processing configuration, it is necessary to raise the temperature in the drying apparatus once lowered to the predetermined temperature when transport is resumed, and there is a problem that it takes time to start up. Further, there is a possibility that the continuous sheet stagnated in the drying apparatus when the continuous sheet conveyance is stopped or restarted is treated as a damaged product.

  The configuration of changing the conveyance path of the continuous sheet in the drying apparatus of Patent Document 1 is merely for shortening the length that the continuous sheet passes through the apparatus. For this reason, the above-described configuration disclosed in Patent Document 1 is an effective solution configuration for requiring a start-up time and generating a defective product due to the stagnation of the continuous sheet in the apparatus as described above. It cannot be provided.

  An object of the present invention is to provide a drying device and a recording device capable of continuing the heating of the drying device even when the conveyance of the sheet is stopped, reducing the restart time, and protecting the sheet in the drying device. Is to provide.

  Therefore, in the present invention, in the drying apparatus, in the heating space, the heating means for heating the conveyed continuous sheet, and when the continuous sheet is stopped, the continuous sheet is retracted out of the heating space. And a retracting means for changing the sheet conveyance path.

  According to the above configuration, it is possible to continue the heating of the drying device even when the conveyance of the sheet is stopped, shorten the restart time, and protect the sheet in the drying device.

1 is a diagram illustrating a schematic configuration of a recording apparatus including a drying apparatus according to an embodiment of the present invention. It is a figure which shows the internal structure of the drying apparatus shown in FIG. (A) And (b) is a schematic diagram of the drive structure of the 1st shutter part shown in FIG. (A) And (b) is a schematic diagram which shows the drive structure of a 2nd shutter part. It is a figure which shows the state which the continuous sheet P is located in the low-temperature space based on one Embodiment of this invention. It is a figure which shows the state which retracted the dancer roller to the position which the continuous sheet | seat and the dancer roller do not contact based on one Embodiment of this invention, or slackened the continuous sheet | seat. It is a figure which shows the state which moved and stopped the dancer roller to the desired position in heating space. It is a flowchart which shows the control at the time of a drying start based on one Embodiment of this invention. It is a flowchart which shows the control at the time of a dry stop based on one Embodiment of this invention. It is a flowchart which shows the control at the time of drying resumption based on one Embodiment of this invention. (A) And (b) is a figure explaining control of the conveyance speed of the continuous sheet which stays in the heating space based on one Embodiment of this invention. (A)-(d) is a figure explaining the positional relationship of the heating space and sheet | seat accompanying the drying operation which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram showing a schematic configuration of a recording apparatus including a drying apparatus according to an embodiment of the present invention. The recording apparatus shown in FIG. 1 is roughly configured to include a winding unit 1, an image forming unit 2, a drying device 3, a winding unit 4, and a buffer unit 5. A two-roll recording device.

  The unwinding unit 1 holds the continuous sheet P wound in a roll shape and supplies the continuous sheet P to the image forming unit 2. The image forming unit (recording unit) 2 performs recording on one side or both sides of the continuous sheet P, and conveys the continuous sheet P to the drying device 3 located on the downstream side in the conveyance direction of the sheet P. Recording is performed on the continuous sheet P for each recording unit in the conveyance direction. In this specification, the recording unit is a repeating unit such as one page or a unit image. The length of the unit image varies depending on the image size to be recorded. For example, the length in the sheet conveyance direction is 135 mm for the L size photograph, and the length in the sheet conveyance direction is 297 mm for the A4 size. The image forming unit 2 of the present embodiment performs recording by an ink jet method. The recording method is not limited to this, and for example, an electrophotographic method, a dot impact method, a liquid developing method, or the like can be used. Further, the continuous sheet P is not limited to paper, and a medium capable of absorbing a liquid such as an ink such as a film or a fabric can be used.

  As will be described later with reference to FIG. 2 and the subsequent drawings, the drying device 3 dries the continuous sheet P recorded by the image forming unit 2.

  The winding unit 4 winds the continuous sheet P discharged through various processes into a roll shape. The buffer unit 5 is located between the unwinding unit 1 and the winding unit 4 and adjusts the slack and tension of the continuous sheet P.

  The drying apparatus shown in FIG. 1 is a form attached to the recording apparatus, but is not limited to recording, and includes a recording machine, a copying machine, a coating machine, and various devices including a drying process such as coating and processing with a solution. The present invention can be widely applied to manufacturing apparatuses.

  FIG. 2 is a diagram showing an internal configuration of the drying apparatus shown in FIG. As shown in FIG. 2, the drying device 3 includes a high-temperature heating space 6 and a relatively low-temperature low-temperature space 7 (non-heating space) adjacent to the high-temperature heating space 6. The heating space 6 is a space for evaporating moisture contained in the continuous sheet P. The low temperature space 7 is a space where the temperature is lower than that of the heating space 6 and drying is not performed. In other words, it can be said that the low-temperature space 7 is a space in which the sheet P is not deteriorated or deformed due to the influence of heat while the sheet P is present.

  The continuous sheet P is fed from the upstream side in the sheet conveying direction within the drying device 3 to the first roller 8, the second roller 9, the dancer roller 10, the third roller 11, the fourth roller 12, the fifth roller 13, and the sixth roller pair 14. Is discharged to the outside of the drying device 3. That is, the sheet P is driven by these rollers and guided to dry the sheet P during its conveyance. In addition, in the said path | route in the drying apparatus 3, the continuous sheet P is conveyed without contact | abutting a roller etc. to the solution application | coating surface until it passes the heating space 6, Thereby, migration can be suppressed.

  The dancer roller 10 is driven to move in the vertical direction in the apparatus, and can move between the heating space 6 and the low temperature space 7. The dancer roller 10 has a drive mechanism that adjusts the position of the dancer roller 10 to move in the heating space 6 and stops at the adjusted position. With this configuration, the continuous sheet P is conveyed in the heating space 6 or the low temperature space 7 in the drying device 3 in response to the movement of the dancer roller 10. When the dancer roller 10 moves, the sheet conveyance path can be changed so that the continuous sheet P is retracted out of the heating space 6 when the conveyance of the continuous sheet P is stopped. In other words, the dancer roller 10 and its driving mechanism constitute a retreat means for retreating the continuous sheet P out of the heating space 6.

  A heating unit 15 is provided in the heating space 6. The continuous sheet P whose transport path is transferred to the heating space 6 by the dancer roller 10 passes through the heating unit 15. The heating unit 15 includes a heater for heating (heating) air to generate hot air, and a fan (not shown) for circulating the hot air in the heating space 6 and blowing hot air on the continuous sheet P. I have. As the continuous sheet P passes through the heating unit 15, moisture contained in the continuous sheet P evaporates. The heating configuration of the heating unit 15 is not limited to the configuration in which hot air is blown. For example, the continuous sheet P may be heated and dried by various heating methods such as a combination with heating by a far infrared heater and hot air blowing.

  When the continuous sheet P having a high water content is continuously dried, the internal humidity of the heating space 6 is increased and the drying efficiency is lowered. Therefore, the hot air circulating in the heating space 6 and the air outside the drying device 3 having a lower humidity than the inside of the heating space 6 are exchanged to reduce the humidity of the circulating hot air. The hot air circulating in the drying device 3 is exchanged with external air in a range up to about 15% of the circulating hot air flow rate. The internal air to be exhausted is exhausted through the exhaust port 16. External air is taken in from an intake port in the heating unit 15 (not shown).

  The first shutter portions 17 a and 17 b and the second shutter portion 18 are opening / closing mechanisms for separating the low temperature space 7 and the heating space 6. In order to put the continuous sheet P and the dancer roller 10 in and out of the heating space 6, a gap that does not interfere with other structures is necessary. On the other hand, the wider the gap, the easier the heat leaks to the outside of the heating space 6, resulting in a decrease in drying efficiency and exposure of areas other than the heating space 6 such as the low-temperature space 7 to the heat. Therefore, the first shutter portions 17a and 17b and the second shutter portion 18 are moved in response to the drive of the dancer roller 10 so as to narrow the gap generated between the low temperature space 7 and the heating space 6 as much as possible.

  FIGS. 3A and 3B are schematic views of the drive structure showing the first shutter portion shown in FIG. 2, wherein FIG. 3A is when the shutter is closed, and FIG. 3B is when it is opened. Indicates the state. As shown in these drawings, the first shutter portions 17a and 17b are opened and closed in the form of these two sliding doors. The first shutter portions 17a and 17b can be linearly moved by the first shutter portion linear guide 20. The first shutter unit driving motor 21, the first shutter unit driving belt 22, and the first shutter unit driving pulley 23 drive the first shutters 17a and 17b to open and close in the horizontal direction.

  4 (a) and 4 (b) are schematic views showing the driving structure of the second shutter portion, in which FIG. 4 (a) shows a closed state and FIG. 4 (b) shows a opened state. The second shutter unit 18 of the present embodiment opens and closes by vertical movement of the second shutter unit 18. That is, the second shutter portion 18 can be vertically moved by the second shutter portion linear motion guide 24, and the second shutter portion 18 is vertically moved by driving the second shutter portion driving ball screw 25 and the second shutter portion driving motor 26. Open and close in the direction.

  Next, the operation in the drying apparatus of this embodiment will be described.

  FIG. 2 shows a state where the continuous sheet P is located in the heating space 6. That is, this state is a state when the sheet 6 is dried while the continuous sheet P is conveyed in the heating space 6. The continuous sheet P is guided into the heating space 6 with the movement of the dancer roller 10 and is in the state shown in the figure. At this time, the opening 19 of the heating space 6 is closed by the first shutter portions 17a and 17b and the second shutter portion 18 leaving only a gap through which the continuous sheet P passes.

  FIG. 5 is a diagram illustrating a state in which the continuous sheet P is positioned in the low temperature space 7. The state shown in FIG. 5 is a state when the continuous sheet P is loaded and unloaded to the drying apparatus 3 or when the apparatus is started up. Alternatively, when a job stop command is input, or during maintenance, when the conveyance is stopped due to a jam occurring in another unit constituting the recording apparatus shown in FIG. 1, the state shown in FIG. . That is, as shown in FIG. 5, the dancer roller 10 is moved into the low temperature space 7, whereby the continuous sheet P is also positioned in the low temperature space 7. At this time, the first shutter portions 17 a and 17 b close the opening 19 of the heating space 6 and thermally separate the heating space 6 and the low temperature space 7. That is, even if the heating space 6 is heated by the heating unit 15, it is possible to suppress the heat from being transmitted to the low temperature space 7. Thereby, the continuous sheet P which exists in the low temperature space 7 is not exposed to the high temperature by the heating part 15, and can suppress the damage by heat. Moreover, the heating in the heating space 6 can be continued, and the re-start-up time caused by temporarily stopping the heating can be omitted. Furthermore, since the operator of the apparatus can load and unload the continuous sheet P in the low temperature space 7, work can be started without waiting for the heating space 6 to cool.

  In FIG. 6, after the dancer roller 10 is retreated from the heating space 6 and moved to the low temperature space 7, the dancer roller 10 is retreated to a position where the continuous sheet P and the dancer roller 10 do not contact or the continuous sheet P is loosened. It is a figure which shows a state. The surface of the dancer roller 10 withdrawn from the heating space 6 is in a high temperature state for a while after being withdrawn due to the heat capacity. If the surface is kept in contact with the high-temperature dancer roller 10 for a long time, there is a concern about deterioration due to heat due to the promotion of drying variation at the non-contact portion and the type of the continuous sheet P. For such a case, it is effective to take the form shown in FIG.

  FIG. 7 is a view showing a state in which the dancer roller 10 is moved to a desired position in the heating space 6 and stopped. The position of the dancer roller 10 shown in FIG. 2 is the same, and an example of the stop position of the dancer roller 10 is shown. For example, the recording contents recorded on the continuous sheet P and the material of the continuous sheet P are various, and accordingly, when the moisture contained in the continuous sheet P is small or conversely, the continuous sheet P transmits heat. It may be easy. For this reason, the heating temperature or drying time required in the heating space 6 varies depending on the recording content and the material of the continuous sheet. On the other hand, when dealing with this by changing the set value of the heating temperature, it takes a relatively long time to reach the set value temperature. For example, when a recording unit of a recording content with a small amount of ink is sandwiched or a recording unit such as a thin continuous sheet recording is sandwiched while a recording unit with a constant amount of ink ejection continues, Responsiveness is better and more effective when the drying time is adjusted than the heating temperature. From this point, in this embodiment, it is assumed that the drying time is controlled according to the recording contents and the like, and this drying time is adjusted by controlling the transport distance in the heating space 6 on the basis of the transport speed. That is, as shown in FIG. 7 (or FIG. 2), the position of the dancer roller 10 in the heating space 6 is determined according to the drying time to be controlled, and thereby the drying time of the continuous sheet P is adjusted.

  FIG. 8 is a flowchart showing control at the start of drying according to the present embodiment. When a control command for starting the drying process is received and the inside of the heating space 6 reaches a temperature equal to or higher than the threshold value (S101), the dancer roller 10 is moved to move the conveying path of the continuous sheet P to the heating space 6 to start drying. To do. That is, the continuous sheet P located in the low temperature space 7 is moved to the heating space 6 by the movement (S103) of the dancer roller 10 whose conveyance path is responsive to the opening of the first shutter portions 17a and 17b (S102). . When the dancer roller 10 reaches a predetermined position corresponding to the drying time in the heating space 6 (S104), the second shutter unit 18 is driven to close the opening 19 (S105). By closing the opening 19 by the second shutter portion 18, the opening 19 is closed leaving only a gap through which the continuous sheet P passes, and heat leakage is suppressed. Here, when the continuous sheet P is initially charged, a predetermined waiting time is provided so that the entire surface to be dried of the continuous sheet P loaded in the heating space 6 is sufficiently dried (S106). The predetermined time is a required time when the dancer roller 10 stays at a predetermined position and passes through the heating space 6 at a steady conveyance speed. After the closing by the second shutter unit 18 and the elapse of a predetermined time, the conveyance of the continuous sheet P is started (S107).

  FIG. 9 is a flowchart showing the control when the drying is stopped. The drying stop command is issued when an operation command or a jam occurs (S201). The second shutter unit 18 is opened in response to the stop command (S202). The dancer roller 10 moves away from the heating space 6 to the low temperature space 7 in response to the opening of the second shutter portion 18 (S203). The first shutter portions 17a and 17b close the opening 19 after the dancer roller 10 is retracted (S204) (S204). Here, since the surface of the dancer roller 10 immediately after retreating from the heating space 6 is at a high temperature, the dancer roller 10 may be retreated to a position where it does not contact the continuous sheet P as shown in FIG.

  FIG. 10 is a flowchart showing the control when resuming drying. As shown in the figure, this control partially overlaps the process shown in FIG. The drying restart command is issued by an operation command, and this process is started. The position of the continuous sheet P is adjusted in the transport direction by the upstream or downstream device of the drying device 3 according to the previous stop position (S301). When the inside of the heating space 6 reaches a predetermined temperature equal to or higher than the threshold value after the position adjustment is finished (S101), the conveyance path of the continuous sheet P is moved to the heating space 6 and drying is resumed. That is, the continuous sheet P positioned in the low temperature space 7 is moved to the heating space 6 by the movement of the dancer roller 10 in response to the opening of the first shutter portions 17a and 17b (S102) in the conveyance path (S103). When the dancer roller 10 reaches a predetermined position (S104), the second shutter unit 18 is driven and the opening 19 is closed (S105). When the opening 19 is closed by the second shutter portion 18, the opening 19 can be closed leaving only a gap through which the continuous sheet P passes, and heat leakage can be suppressed. When the closing by the second shutter unit 18 is completed, the conveyance of the continuous sheet P is resumed (S107).

  The continuous sheet P that is put into the heating space 6 or re-inserted after evacuation and stays in the heating space 6 is sufficiently dried by the above-described control and then discharged. However, depending on the requirements for the product such as the heat resistance and recording quality of the continuous sheet P, the continuous sheet P may be processed as a damaged product due to the influence of heat when staying in the heating space 6. Therefore, in the present embodiment, the conveyance speed is controlled for the continuous sheet P staying in the heating space 6 so as to prevent it from being damaged.

FIGS. 11A and 11B are diagrams for explaining the control of the conveyance speed of the continuous sheet P staying in the heating space 6. In the figure, the continuous conveyance speed of the continuous sheet P is V ₀ , the conveyance speed upstream of the dancer roller 10 in the conveyance direction is V _U , the conveyance speed of the downstream side is V _L , and the movement speed of the dancer roller 10 is V _H. , Respectively. Further, the front and rear end positions of the continuous sheet P staying in the heating space 6 immediately before the conveyance of the continuous sheet P is indicated by A and B, respectively.

FIG. 11A shows speed control when the dancer roller 10 is retracted from the heating space 6. At the time of evacuation, only the downstream side of the continuous sheet P in the heating space 6 is fed with V _L = V ₀ , and the dancer roller 10 is moved with V _H = 0.5V ₀ . On the other hand, FIG. 11B shows speed control when the dancer roller 10 is re-entered into the heating space 6 after retreating. First, the rear end B of the continuous sheet P at the time of the previous retreat is moved to the front end position on the upstream side of the heating space. After the tip position is set to B, only the upstream side of the continuous sheet P in the heating space 6 is fed at V _U = V ₀ and the dancer roller 10 is turned on at V _H = 0.5V ₀ . By controlling the conveyance speed as described above, when the dancer roller 10 is retracted, the already heated and dried sheet portion can be discharged from the heating space 6 first. In addition, when the dancer roller 10 is inserted, the already heated and dried sheet portion can be prevented from returning to the heating space. Thereby, the variation (heating time difference) of the heating amount, that is, the heating time, between the parts of the sheet can be suppressed.

  When the dancer roller 10 reaches a predetermined position, downstream feeding is also started and steady operation is performed. 11B is the same as that shown in FIG. 11B, and the leading edge of the continuous sheet P at the time of initial charging is the position B. However, there is a possibility that the amount of heat transferred to the continuous sheet P at the time of retraction / loading varies depending on the arrangement of the rollers that contact the dancer roller 10 and the other continuous sheet P and the shape of the heating unit. In such a case, the above parameters may be multiplied by a correction coefficient to provide speed adjustment or arbitrary wait time according to the system of the drying apparatus.

(Second Embodiment)
The drying apparatus of the present invention is not limited to the configuration in which the dancer roller 10 is moved in the vertical direction shown in FIG. What is necessary is just to satisfy | fill the structure which can retract | save relatively the heating space provided with the mechanism which heats the continuous sheet P conveyed, and the continuous sheet P. FIG.

  12A to 12D are views for explaining the positional relationship between the heating space and the sheet accompanying the drying operation according to the second embodiment of the present invention. These drawings show that the continuous sheet P is retracted from the heating space 6 in the first embodiment, whereas the heating space 6 is retracted from the continuous sheet P in the present embodiment.

  FIG. 12A shows the positional relationship between the sheet P and the heating space 6 when the continuous sheet P is heated. At this time, the first shutter portions 17a and 17b are closed. At the time of heating indicated by this positional relationship, the heating space 6 enters the space to be the low temperature space 7. FIG. 12B shows a state in which the first shutter portions 17a and 17b are opened, whereby another heating space 6 provided with the heating portion 15 is separated by the first shutter portions 17a and 17b. It can be retreated to the room. Alternatively, in this state, the heating space 6 can be moved to the position shown in FIG. 12A where the sheet is heated.

  FIG. 12C shows a state when the heating space 6 is relatively retracted from the continuous sheet P. The first shutter portions 17 a and 17 b are closed, and the low temperature space 7 where the sheet P exists is separated from the heating space 6. As a result, the retreated heating space 6 can be stopped without stopping the heating, and the sheet P can be prevented from being altered or deformed by unnecessary heat.

  FIG. 12D shows a state where the heating space 6 is at the retracted position and the first shutter portions 17a and 17b are opened. In this state, the heating space 6 provided with the heating unit 15 can be reintroduced. The heating space 6 provided with the heating unit 15 moves in the drying device 3 by a linear drive mechanism (not shown). The first shutter portions 17a and 17b in the second embodiment are also opened and closed by a first shutter drive belt 22 (not shown) as in the first embodiment.

  Note that the opening and closing methods of the first shutter portions 17a and 17b and the second shutter portion 18 that separate the heating space 6 and the low temperature space 7 are not limited to the examples shown in the above embodiments. For example, a mechanism that separates at least two or more spaces such as a rotating door, a folding door, and an air curtain may be used.

  As described above, according to the embodiment of the present invention, the operation of the drying apparatus can be continued even if the continuous sheet conveyance is stopped due to maintenance of the accompanying apparatus or jamming, and the time until restart Can be shortened. Further, since the continuous sheet is not exposed to a high temperature for a long time, damage to the continuous sheet due to heat can be reduced.

P continuous sheet 2 image forming unit 3 drying device 6 heating space 7 low temperature space 10 dancer roller 15 heating unit 17a, 17b first shutter unit 18 second shutter unit 19 opening

Claims (9)

Heating means for heating the continuous sheet conveyed in the heating space;
A drying apparatus comprising: a retracting unit that changes a sheet transport path so that the continuous sheet is retracted out of the heating space when the transport of the continuous sheet is stopped.   The drying apparatus according to claim 1, wherein the retracting unit includes a mechanism that moves the conveyance path between the heating space and a non-heating space adjacent to the heating space.   The drying apparatus according to claim 1, wherein the retracting unit includes a mechanism that moves the heating space.   The drying apparatus according to claim 2, wherein the retracting unit includes a dancer roller that guides a continuous sheet, and a mechanism that moves the dancer roller between inside and outside the heating space.   The drying apparatus according to claim 4, wherein the dancer roller moves away from the continuous sheet when the dancer roller moves out of the heating space.   Opening / closing means provided between the heating space and a non-heating space adjacent to the heating space is provided, and the opening / closing means is closed when the transport path does not pass through the heating space. The drying device according to any one of claims 1 to 5.   The drying apparatus according to any one of claims 1 to 6, wherein when the retracting unit changes the conveyance path, the conveyance speed of the continuous sheet is changed.   The time during which the continuous sheet is conveyed through the heating space is controlled according to at least one of the type of the continuous sheet and the amount of water contained in the sheet. Drying equipment.   A recording apparatus comprising: a recording unit that performs recording on a sheet; and a drying device according to claim 1 that dries the sheet recorded by the recording unit.

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