Recording device and control method

Abstract

To provide a technology capable of controlling heating of a sheet depending on recording conditions.SOLUTION: A recording apparatus of the present invention includes: conveyance means for conveying a sheet along a conveyance path; recording means for recording an image by discharging ink to the sheet conveyed by the conveyance means; first heating means for heating the sheet on which the image is recorded by the recording means, in a heating section on the conveyance path; control means for controlling the first heating means so that the heating section can be changed depending on recording conditions.SELECTED DRAWING: Figure 3A

Description

[Technical field]

[0001] The present invention relates to recording technology. [Background technology]

[0002] In a method of ejecting ink onto a sheet to record an image, the sheet may curl due to the moisture contained in the ink. Therefore, a technique for heating the sheet to promote drying has been proposed. For example, Patent Document 1 discloses a technique for promoting drying by blowing hot air onto a sheet on which an image has been recorded. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 10201985 Summary of the Invention [Problem to be solved by the invention]

[0004] The heating mode suitable for drying the sheet may differ depending on the recording conditions. For example, when the sheet transport path is different for single-sided recording and double-sided recording, if the sheet is heated in the same section on the transport path for both, unnecessary or inappropriate heating may be applied to the sheet. This may result in the sheet being over- or under-dried, or may result in an unnecessary rise in the temperature inside the device and waste of power.

[0005] The present invention provides a technique capable of controlling the heating of a sheet in accordance with recording conditions. [Means for solving the problem]

[0006] According to the present invention, a conveying means for conveying the medium in a conveying direction along a conveying path including an inversion path for inverting a first surface and a second surface of the medium; a recording means for ejecting ink onto the first surface of the medium that is transported without passing through the reversing path, and for ejecting ink onto the second surface of the medium that is transported through the reversing path; downstream of the recording means in the transport direction a heating unit that heats the medium in a first region and heats the medium in a second region downstream of the first region in the transport direction, When the heating means heats the medium in the first region In , In the case of the first recording condition Heating by the heating means is performed in at least a part of the second region. In the case of the second recording condition, the heating is not performed in the second region by the heating means. , The heating means blows hot air from a plurality of blowing holes, Among the plurality of blowing holes for heating the medium, the blowing holes in the first region are positioned differently from at least a part of the blowing holes in the second region. A recording device is provided. Effect of the Invention

[0007] According to the present invention, it is possible to provide a technique capable of controlling the heating of a sheet in accordance with recording conditions. [Brief description of the drawings]

[0008] [Figure 1] FIG. [Diagram 2] FIG. [Figure 3A] FIG. [Figure 3B] FIG. [Figure 4] FIG. [Diagram 5] FIG. 4 is a block diagram of a control unit of the main unit. [Figure 6] FIG. 3 is a diagram illustrating the operation of the recording apparatus in FIG. 2. [Figure 7] FIG. 3 is an explanatory diagram of the operation of the recording apparatus in FIG. 2. [Figure 8] FIG. 3 is a diagram illustrating the operation of the recording apparatus in FIG. 2. [Figure 9] FIG. 3 is an explanatory diagram of the operation of the recording apparatus in FIG. 2. [Figure 10] 6A and 6B are flowcharts showing an example of control. [Figure 11] FIG. 11 is an explanatory diagram of a drying promotion unit according to another example. [Figure 12] FIG. 11 is an explanatory diagram of a drying promotion unit according to another example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, the embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments do not limit the invention according to the claims. Although the embodiments describe a number of features, not all of these features are essential to the invention, and the features may be combined in any manner. Furthermore, in the attached drawings, the same reference numbers are used for the same or similar configurations, and duplicated descriptions are omitted.

[0010] First Embodiment <Recording system configuration> Fig. 1 is a front view of a recording system 1 according to an embodiment of the present invention. In each of the drawings including Fig. 1, an arrow X indicates the left-right direction, an arrow Y indicates the depth direction, and they are perpendicular to each other. An arrow Z indicates the up-down direction.

[0011] The recording system 1 includes a main unit 2 and a post-processing device 3. The main unit 2 in this embodiment is a device that constitutes a multifunction peripheral, and has a copying function, a scanner function, and a printer function. The main unit 2 includes a reading device 4, a recording device 5, and a feeding device 6, and an operation unit 7 is provided on the front of the main unit 2. The operation unit 7 is an input / output interface with the user, and includes, for example, hard keys and a display unit, or a touch panel that accepts user input and displays information, and also includes an output unit such as a sound generator.

[0012] The reading device 4 includes an ADF (automatic document feeder) and transports stacked documents and reads document images. The feeding device 6 is a device that feeds recording media to the recording device 5. In this embodiment, the recording media are sheets such as paper or film, and in particular cut sheets. The recording media may also be called sheets. The feeding device 6 includes a plurality of cassettes 6a on which sheets are stacked, and a feeding mechanism (not shown) that feeds sheets from the cassettes 6a to the recording device 5 on the transport path RT.

[0013] The recording device 5 records an image on a sheet. The recording device 5 includes a recording unit 30 that ejects ink onto a sheet to record an image, and drying acceleration units 40 and 50 that accelerate drying of the sheet. The recording device 5 will be described in detail later.

[0014] The post-processing device 3 is a finisher (sheet processing device) that is detachably attached to the side of the main body device 2 as an optional device and performs post-processing of sheets. Examples of post-processing include a stacking process in which sheets discharged from the recording device 5 are stacked on a tray 3a, a sorting process in which multiple sheets discharged from the recording device 5 are sequentially taken in and aligned to form a bundle, a stapling process in which the bundled sheets are stapled, a bookbinding process, and a hole punching process.

[0015] <Recording device configuration> 2 is an explanatory diagram showing the internal structure of the recording device 5. The recording device 5 includes a bottom wall 5a, an upper wall 5b, a right wall 5c, a left wall 5d, and a rear wall 5e as a frame supporting the internal mechanism. These walls define the internal space of the recording device 5. The internal space of the recording device 5 is further divided into a lower space SP1 and an upper space SP2 by a partition wall 5h. The spaces SP1 and SP2 are not separated airtight, but communicate with each other.

[0016] The bottom wall portion 5a has an opening 5f through which a sheet fed from the feeding device 6 passes. In addition, the right wall portion 5c has an opening 5g through which a sheet discharged to the post-processing device 3 passes. The left wall portion 5d and the right wall portion 5c may be supported in the form of a door that can be opened and closed for maintenance purposes.

[0017] The recording apparatus 5 includes a transport unit 20, a recording unit 30, drying promotion units 40 and 50, a straightening unit 60, and an exhaust unit .

[0018] <Transport unit> The transport unit 20 is a mechanism for transporting a sheet along a transport path RT. In this embodiment, the transport path RT is a path along which a sheet is transported, with the opening 5f as the upstream end and the opening 5g as the downstream end. The transport path RT includes main paths RT1 and RT2, a switchback path RT3, and a reversing path RT4. The main paths RT1 and RT2 are paths that connect the opening 5f to the opening 5g through the midpoint M1, and the main path RT1 is from the opening 5f to the midpoint M1, and the main path RT2 is from the midpoint M1 to the opening 5g. The main paths RT1 and RT2 are paths that transport a sheet in the left direction →upward direction →right direction, and the sheet passes through the recording unit 30 →drying promotion unit 40 →drying promotion unit 50 →correction unit 60 in this order. In the case of single-sided recording in which only one side of the sheet is recorded, the sheet is transported through the main paths RT1 and R2.

[0019] The switchback path RT3 and the reversing path RT4 are formed by branching off from the main path RT1, and are paths along which a sheet after one-side printing is transported in the case of double-sided printing, in which both sides of the sheet are printed. The switchback path RT3 forms a path from the midpoint M1 to the main path RT2. The reversing path RT4 is a path from the midpoint M1 to the junction M2 midway along the main path RT1, and by passing through the reversing path RT4, the sheet is reversed and returned to the main path RT1.

[0020] In the following description, when referring to the downstream side and the upstream side, the conveying direction of the sheet on the conveying path RT is used as a reference.

[0021] The transport unit 20 includes a drive mechanism that applies a transport force to the sheet and a guide that guides the transport of the sheet along the transport path RT, and a part of the drive mechanism is shown in FIG. 2. The drive mechanism includes a plurality of transport rollers 21 driven by a drive source such as a motor. A driven roller or a spur is disposed opposite each transport roller 21. The sheet is transported while being sandwiched between the transport roller 21 and the driven roller or the spur. The spur is disposed in a region downstream of the recording unit 30 so as to contact the recording surface side in order to maintain the quality of the recorded image. The guide includes guide members 22 to 24. The guide member 24 is supported by the left wall portion 5d. A part of the transport path RT is formed between the guide member 23 and the guide member 24, and a part of the path RT1 is formed between the guide member 22 and the guide member 24.

[0022] The transport unit 20 also includes path switching units 25 and 26. The path switching units 25 and 26 are units that switch the guide path of the sheet, and are operated by a driving source such as an electromagnetic solenoid or a motor. In the case of single-sided recording, the path switching units 25 and 26 guide the sheet from the main path RT1 to the main path RT2, and in the case of double-sided recording, the path switching units 25 and 26 guide the sheet from the main path RT1 to the switchback path RT3, and guide the switched-back sheet to the inversion path RT4. FIG. 3 shows the path switching manner of the path switching units 25 and 26. The path switching units 25 and 26 each include a rotatable flap, and switch the path depending on the position of the flap. The position indicated by the solid line is the position in the case of single-sided recording, and the position indicated by the dashed line is the position in the case of double-sided recording. Sheet sensors that detect the presence or absence of a sheet are arranged at various points on the transport path RT, and the position of the sheet on the transport path RT is specified based on the detection result of the sheet sensor.

[0023] <Recording unit> Returning to Fig. 2, the recording unit 30 includes a recording head 31, which is an inkjet head that ejects ink onto a sheet to form an image (ink image). The ink ejected by the recording head 31 is stored in a plurality of ink storage sections T. An ink storage section T is provided for each type of ink, and the types of ink are, for example, color types such as yellow, magenta, cyan, and black.

[0024] A recording head 31 is provided for each type of ink. In this embodiment, each recording head 31 is a full line head extending in the Y direction, and nozzles are arranged in a range that covers the width of the image recording area of ​​a sheet of the maximum size that can be used. The recording head includes a lower surface that faces the sheet via a minute gap (for example, a few mm), and this lower surface forms an ink ejection surface with nozzles opening therein.

[0025] Each nozzle is provided with an ejection element. The ejection element is, for example, an element that generates pressure in the nozzle to eject ink in the nozzle, and known inkjet head technology can be applied to the ejection element. Examples of the ejection element include an element that ejects ink by generating film boiling in the ink using an electro-thermal converter to form bubbles, an element that ejects ink using an electro-mechanical converter, and an element that ejects ink using static electricity. By using an ejection element that uses an electro-thermal converter, high-speed and high-density recording can be performed.

[0026] The recording unit 30 may be a serial type recording unit in which a recording head mounted on a carriage moves back and forth in the width direction of the sheet to perform recording. The ink to be ejected may be one type, such as black ink only. The recording mode of the recording unit 30 may be selectable between a single ink recording mode and a multiple ink recording mode. The ink may mainly contain a coloring agent (dye or pigment) and a solvent component. The solvent component may be either a water-based material or an oil-based material. As the dye, for example, a water-soluble dye represented by direct dye, acid dye, basic dye, reactive dye, food coloring, etc. is preferable, and any dye may be used as long as it gives an image that satisfies the required performance such as fixability, color development, clarity, stability, light resistance, etc., when combined with the above-mentioned recording medium. As the pigment, carbon black, etc. is preferable. A method of using a pigment and a dispersant in combination, a method of using a self-dispersing pigment, or a method of microencapsulation are also possible. In addition, various additives such as a solvent component, a solubilizer, a viscosity adjuster, a surfactant, a surface tension adjuster, a pH adjuster, and a resistivity adjuster can be added to the ink as necessary. Also, instead of providing a recording head 31 for each type of ink, a single recording head may be provided with nozzles for each type of ink.

[0027] <Drying acceleration unit> A sheet on which an image is recorded by the recording unit 30 may expand due to the liquid content of the ink, causing undulations. Such a sheet can cause paper jams in the recording device 5 and deteriorate the stackability / alignment in the post-processing device 3. By promoting drying of the sheet, it is possible to suppress the expansion of the sheet due to the liquid content of the ink. The recording device 5 of this embodiment has in common the point of heating the sheet, but includes multiple drying promotion units 40 and 50 which have different sheet drying methods. The liquid content of the ink contains a certain amount of moisture.

[0028] The drying promotion unit 40 is disposed downstream of the recording unit 30, and is a unit that heats the sheet by blowing hot air to the sheet in a predetermined heating section on the transport path RT, and promotes the drying of the sheet without contacting the sheet. The structure of the drying promotion unit 40 will be described with reference to Figs. 2, 3A, and 3B.

[0029] The drying promotion unit 40 includes a hollow body 41 that defines an internal space, and a fan 42 and a heating element 43 that are arranged inside the hollow body 41. The hollow body 41 has an air intake 41a on its right side. A wall portion 41b that forms the left side of the hollow body 41 is a guide wall portion that also serves as a sheet conveying guide, and is extended in the Y direction so as to cover the width of a maximum size sheet. The guide wall portion 41b has a C-shaped cross section (cross section on the XZ plane) and has a wall surface that faces the guide members 22 to 24. A part of the conveying path RT is formed between this wall surface and the guide members 22 to 24, and a midpoint M1 is also set. A number of hot air blowing holes N that communicate with the internal space of the hollow body 41 are formed in the guide wall portion 41b.

[0030] The fan 42 is an electric fan, such as a sirocco fan, driven by a motor. The fan 42 introduces air into the hollow body 41 from the intake port 41a. The introduced air increases the air pressure inside the hollow body 41, and the air inside the hollow body 41 is blown out of the hollow body 41 from the blowing hole N. There may be only one fan 42, or multiple fans 42 may be arranged side by side in the Y direction.

[0031] The heating element 43 heats the air introduced into the hollow body 41 from the intake port 41a by the fan 42. In this embodiment, the heating element 43 is a rod-shaped heating element such as an infrared lamp heater, and is extended in the Y direction. A plurality of heating elements 43 are arranged in the Z direction. The plurality of heating elements 43 are disposed between the fan 43 and the intake port 41a, and the air introduced into the hollow body 41 from the intake port 41a is heated as it passes through the heating elements 43. The drying promotion unit 40 is provided with a temperature sensor 44, and the operation of the heating element 43 is controlled based on the detection result of the temperature sensor 44.

[0032] With this configuration, the drying promotion unit 40 blows hot air from the blowing holes N as the airflow is indicated by the arrow in Fig. 3. This heats the sheet passing through the transport path RT, promotes evaporation of the liquid contained in the ink image on the sheet, and promotes drying of the sheet.

[0033] The drying promotion unit 40 is provided with a shutter unit 45 that changes the blowing hole N from which hot air is blown out. By changing the blowing hole N from which hot air is blown out, the heating section on the transport path can be changed.

[0034] FIG. 3A is an explanatory diagram of the heating section. In the illustrated example, a heating section R1 and a heating section R2 are illustrated. The heating section R2 is the entire section in which hot air can be blown out from the drying promotion unit 40, and the heating section R1 is a part of the heating section R2. Therefore, the heating section R2 is a section longer than the heating section R1. The heating section R2 includes a downstream portion of the main path RT1 (from the starting point of blowing hot air by the drying promotion unit 40 to the midpoint M1), an upstream portion of the main path RT2 (the portion around the midpoint M1), and a switchback path RT3. The heating section R1 includes a downstream portion of the main path RT1 (from the starting point of blowing hot air by the drying promotion unit 40 to the midpoint M1) and an upstream portion of the main path RT2 (the portion around the midpoint M1).

[0035] In this embodiment, the heating section can be changed to two types, but the heating section can be changed to three or more types. The three or more types of heating sections may have different lengths, and the shorter heating section may be a part of the longer heating section.

[0036] The shutter unit 45 includes a shutter 450 and a drive unit 451 that moves the shutter 450 back and forth in the Y direction. FIG. 3B shows the movement of the shutter 450, and is a view of a part of the wall 41b in the direction of the arrow D1 in FIG. 3A. The shutter 450 is disposed inside the wall 41b and is a plate-like member having a shape that conforms to the inner surface of the wall 41b. The shutter 450 has a size that overlaps only a part of the upper side of the wall 41b, and its width (width in the Y direction) covers the entire area of ​​the formation area of ​​the blowing holes N of the wall 41b. In FIG. 3B, a pattern is applied to the shutter 450 in order to make it easier to visually understand the shutter 450 located behind the wall 41b. The shutter 450 has a plurality of holes OP corresponding to the plurality of blowing holes N provided in the wall 41b. The holes OP are not patterned.

[0037] The driving unit 451 is, for example, a driving mechanism such as a pull solenoid or an electric cylinder, ball screw mechanism, rack and pinion mechanism, etc., driven by a motor, and slides the shutter 450 in the Y direction. In FIG. 3B, the state STO indicates a state in which the shutter 450 is in the open position, and the state STC indicates a state in which the shutter 450 is in the closed position. When the shutter 450 is in the open position, the holes OP overlap with each blowing hole N, and the blowing hole N is in an open state in which hot air can be blown. The heating section is R2. When the shutter 450 is in the closed position, each blowing hole N does not overlap with the holes OP, but overlaps with the flesh part of the shutter 450, and the blowing hole N is in a closed state in which hot air cannot be substantially blown. The heating section is R1. In this way, the heating section is switched between R1 and R2 by changing the blowing hole N that blows hot air.

[0038] Next, the drying acceleration unit 50 is disposed downstream of the drying acceleration unit 40, and is a heating and fixing device that comes into contact with the sheet to heat the sheet and accelerate the drying of the sheet. The structure of the heating and fixing device will be described with reference to FIG.

[0039] The drying promotion unit 50 includes a heating element 51 and a roller 56, which are extended in the Y direction to cover the width of the maximum size sheet. The heating element 51 includes a support member 53 that supports a heating element 54, which is a heat source. The heating element 54 is, for example, a ceramic heater, and is extended in the Y direction. The temperature of the heating element 54 is detected by a temperature sensor 55, typically a thermistor, and the operation of the heating element 54 is controlled based on the detection result.

[0040] The support member 53 also supports the film 52. The film 52 is cylindrically shaped and extends in the Y direction. The film 52 is supported by the support member 53 so as to be rotatable around the support member 53, and is interposed between the roller 56 and the heating element 54. The film 52 is, for example, a single-layer film or a composite film having a thickness of 10 μm to 100 μm. In the case of a single-layer film, the material is, for example, PTFE, PFA, or FEP. In the case of a composite film, the film has a layered structure in which, for example, a layer of polyimide, polyamideimide, PEEK, PES, PPS, or the like is covered or coated with PTFE, PFA, FEP, or the like.

[0041] The configuration of the heating element 51 is not limited to this structure, and may be, for example, a structure in which a heating element such as a halogen heater is provided inside a hollow metal core shaft, and the periphery of the core shaft is covered with an elastic material such as silicone rubber.

[0042] Roller 56 is configured by covering the peripheral surface of core metal 56a with elastic body 56b such as silicone rubber. Roller 56 is pressed against heating element 51 with a predetermined pressing force, and a nip portion is formed between roller 56 and heating element 51. Roller 56 is rotated by a motor as a drive source, and film 52 rotates along with roller 56. With this configuration, the sheet is heated while being transported in the nip portion, and the drying of the sheet can be promoted.

[0043] In this embodiment, the sheet is dried in two stages by the drying acceleration units 40 and 50, but only one of the drying acceleration units may be provided.

[0044] <Correctional Unit> The straightening unit 60 is a mechanism for straightening the curvature (here, curl) of the sheet. In the present embodiment, the straightening unit 60 includes a large diameter driving roller 61 and a small diameter driven roller 62. The driving roller 61 is a roller in which the periphery of a core metal is covered with an elastic body such as silicone rubber. The driven roller 62 is a metal roller. The driving roller 61 and the driven roller 62 are pressed against each other. When the sheet passes between the driving roller 61 and the driven roller 62, these rollers apply pressure to the sheet, so that the curl of the sheet can be straightened. The straightening unit 60 can apply a straightening force to the sheet in a direction that makes the sheet convex upward, for example. In this case, the sheet having a downward convex curl can be straightened to a flatter shape by the straightening unit 60.

[0045] <Exhaust unit> The exhaust unit 70 is a unit that exhausts the air in the recording device 5 to the outside of the device. The recording device 5 of this embodiment is equipped with drying promotion units 40 and 50, which increase the temperature inside the device. In addition, these units act to evaporate the moisture of the ink. When recording is performed continuously on a large number of sheets, the humidity inside the device may increase. High humidity can cause the sheet to curve. The sheet is transported through a relatively long distance between the drying promotion unit 50 and the opening 5g, and is transported through the upper space SP2 where water vapor is likely to remain. In the space SP2, the sheet may be exposed to a high humidity atmosphere. The humidity inside the device can be reduced by exhausting the air in the space SP2 to the outside of the device using the exhaust unit 70.

[0046] The exhaust unit 70 of this embodiment has a structure in which the air in the space SP2 is naturally exhausted by a plurality of exhaust ducts 71 to 73. However, the exhaust unit 70 may be a type that forcibly exhausts the air in the device by a fan or the like. The structure of the exhaust unit 70 will be described with reference to Fig. 2 and Fig. 4. Fig. 4 is a plan view showing the periphery of the exhaust unit 70, and the upper wall portion 5b is not shown.

[0047] The exhaust duct 71 is a pipe member including an extension portion 71a extending in the Y direction and an extension portion 71b extending from the end of the extension portion 71a on the rear side in the Y direction to the right side in the X direction. The extension portion 71a is extended in the vicinity of the sheet discharge position in the drying promotion unit 50 and at a position lower than the main path RT2. The extension portion 71a is an air intake portion having a plurality of slits serving as air intakes formed in the upper left side and the bottom side. For example, air heated by the drying promotion unit 50 can be introduced from the slit in the upper left side, and for example, hot air blown out from the blowing hole N of the drying promotion unit 40 can be introduced from the slit in the bottom side. The extension portion 71a is extended across the back wall portion 5e, and its end on the rear side in the Y direction and the extension portion 71b are located outside the space SP2 (the rear side in the Y direction). The extension portion 71a may be extended at a position above the main path RT2.

[0048] The exhaust duct 72 is a pipe member including an extension portion 72a extending in the Y direction, a collection portion 72b extending to the right from the extension portion 72a, and an extension portion 72c extending from the right end of the collection portion 72b to the rear side in the Y direction. The extension portion 72a is provided near the sheet discharge position in the drying promotion unit 50 and at a position above the main path RT2. The bottom of the extension portion 72a is open to form an air intake port, through which, for example, air heated by the drying promotion unit 50 or water vapor in the space SP2 is introduced. The extension portion 72a crosses the upper wall portion 5b and protrudes above the upper wall portion 5b.

[0049] The collecting portion 72b has a triangular shape with a wider width on the extension portion 72a side in a plan view, and the entirety is located above the upper wall portion 5b. The collecting portion 72b collects the air introduced into the extension portion 72a at the center in the Y direction at its right end. The collected air flows into the extension portion 72c. The extension portion 72c is also located entirely above the upper wall portion 5b, and is partially bent and extended to the rear side of the rear wall portion 5e. At the rear side of the rear wall portion 5e, the extension portion 71b of the exhaust duct 71 is connected to the extension portion 72c of the exhaust duct 72, and their internal spaces are connected to each other. The extension portion 72c is connected to the exhaust duct 73.

[0050] Exhaust duct 73 is an exhaust member that extends in the X direction and opens to the rear side in the Y direction. The opening of exhaust duct 73 faces cover 8 that forms the exterior of the rear side of main body device 2. A large number of slits (louvers) 8a are formed in cover 8, and air that flows into exhaust duct 73 passes through the slits 8a and is exhausted to the outside of the main body device 2 from the rear side.

[0051] <Control unit> The control system of the main body device 2 will be described. FIG. 5 is a block diagram of the control unit 9 of the main body device 2. The control unit 9 includes a processing unit 10, a storage unit 11, a reading control unit 13, an image processing unit 14, a head control unit 15, an engine control unit 16, and a drying control unit 17. The processing unit 10 is a processor represented by a CPU (Central Processing Unit), and controls the operation of each unit of the main body device 2 in an integrated manner. The storage unit 11 is, for example, a storage device such as a ROM or a RAM. The storage unit 11 stores programs to be executed by the processing unit 10 and fixed data required for various operations of the main body device 2 (for example, data related to the type of sheets contained in each cassette 6a). The storage unit 11 also stores various setting data as a work area for the processing unit 10 or as a temporary storage area for various received data.

[0052] The reading control unit 13 controls the reading device 4. The image processing unit 14 performs image processing of image data handled by the main device 2. It converts the color space (e.g., YCbCr) of the input image data into a standard RGB color space (e.g., sRGB). The recording data obtained by these image processes is stored in the memory unit 11. The head control unit 15 controls the driving of the recording unit 30 in accordance with the recording data based on the control command received from the processing unit 10. The engine control unit 16 controls the conveyance of the sheet, etc. The drying control unit 17 controls the driving of the drying promotion units 40, 50. Each of these control units includes a processor such as a CPU, a storage device such as a RAM or ROM, and an interface with an external device.

[0053] The I / O 12 is an interface (I / F) for connecting the control unit 9 with the host device 18 and the post-processing device 3, and is a local I / F or a network I / F. The host device 18 is a device that serves as a supply source of image data for causing the recording device 5 to perform a recording operation. The host device 18 may be a general-purpose or dedicated computer, or may be a dedicated imaging device such as an image capture device having an image reader unit, a digital camera, or a photo storage device.

[0054] <Control of heating section> The switchback path RT3 included in the heating section R2 is a path through which the sheet is transported in the case of double-sided recording, but is not transported in the case of single-sided recording. If the heating section of the drying promotion unit 40 is uniformly the heating section R2, in the case of single-sided recording in which the sheet is not transported to the switchback path RT3, hot air that does not contribute to drying the sheet is blown to the switchback path RT3. This is a waste of heat generated by the heating element 43 (waste of power consumption). In addition, in the case of this embodiment, since the switchback path RT3 is connected to the space SP2, the hot air blown to the switchback path RT3 flows into the space SP2. The hot air that does not contribute to drying the sheet (has not been heat-exchanged with moisture) causes an unnecessary increase in the temperature of the space SP2. If the temperature of the space SP2 rises, another sheet heading to the straightening unit 60 via the drying promotion unit 50 is heated, and it is assumed that the intended curvature of the sheet cannot be obtained in the straightening unit 60.

[0055] Conversely, if the heating section of the drying acceleration unit 40 is uniformly set to the heating section R1, in the case of double-sided recording in which the sheet is transported to the switchback path RT3, it is assumed that the sheet may not be sufficiently dried.

[0056] Therefore, in this embodiment, the heating section is changed depending on one of the recording conditions of the sheet, that is, single-sided recording or double-sided recording. In other words, the heating section is changed depending on the current conveying path of the sheet among a plurality of conveying paths. This makes it possible to control the heating of the sheet depending on the recording conditions, and to obtain the desired drying of the sheet. FIG. 10(A) is a flowchart showing an example of the control of changing the heating section. The process in this figure is, for example, a control process of the drying promotion unit 40 executed by the drying control unit 17.

[0057] In S1, it is determined whether the image recording conditions for the sheet to be recorded this time are single-sided or double-sided recording. If it is single-sided recording, proceed to S2, and if it is double-sided recording, proceed to S3. In S2, the drive unit 451 is driven to position the shutter 450 in the closed position. The heating section R1 is selected. In S3, it is determined whether the image recording on the front side (hereinafter, the first side), on which the image is to be recorded first, of the front and back sides of the sheet to be recorded this time has been completed, and whether it is time to record an image on the back side (hereinafter, the second side).

[0058] If it is the stage at which an image is to be recorded on the second side, the process proceeds to S2 where the shutter 450 is positioned in the closed position. Heating section R1 has been selected. If it is not the stage at which an image is to be recorded on the second side, but the stage at which an image is to be recorded on the first side, the process proceeds to S4. In S4, the drive unit 451 is driven and the shutter 450 is positioned in the open position. Heating section R2 has been selected. The above process is repeated and the heating section is changed depending on whether single-sided recording or double-sided recording is being performed. In the case of double-sided recording, the heating section is further changed depending on whether it is the first-side recording stage or the second-side recording stage.

[0059] <Example of operation> An example of the recording operation of the recording device 5 under the control of the control unit 9 will be described with reference to Figs. 6 to 9. First, the operation when an image is recorded on one side of a sheet will be described with reference to Figs. 6 and 7. When an image is recorded on one side of a sheet, the path switching units 25 and 26 are set to the positions for one-sided recording (positions shown by solid lines in Fig. 3A). The process of Fig. 10(A) positions the shutter 450 in the closed position and sets the heating section R1. The heating element 43 of the drying promotion unit 40 and the heating element 54 of the drying promotion unit 50 may be maintained at a predetermined temperature in advance.

[0060] State ST1 in Fig. 6 shows a state in which the sheet P fed from the feeding device 6 is transported by the transport unit 20 on the main path RT1 to the recording unit 30, and recording by the recording unit 30 is started. The recording unit 30 ejects ink onto the sheet P as shown by the arrows to record an image. The sheet P is transported toward the drying promotion unit 40. The drying promotion unit 40 starts operating, and hot air is blown onto the sheet P in the heating section R1 (state ST2 in Fig. 6). The hot air promotes drying of the sheet P that is wet with ink.

[0061] The sheet P is further transported on the main path RT2 toward the drying promotion unit 50. The drying promotion unit 50 starts operating, and as shown in state ST3 in FIG. 7, the roller 56 rotates to transport the sheet P, and the sheet P is heated by the heating element 51. The drying of the sheet P is further promoted.

[0062] 7, the sheet P is further transported on the main path RT2 toward the straightening unit 60. The straightening unit 60 starts operating, and the sheet P is discharged from the opening 5g to the post-processing device 3 while the curl of the sheet P is being straightened.

[0063] Next, the operation when recording images on both sides of a sheet will be described with reference to Figures 8 and 9. State ST11 in Figure 8 shows a state in which the sheet P fed from the feeding device 6 is transported by the transport unit 20 on the main path RT1 to the recording unit 30, and recording by the recording unit 30 is started. The recording unit 30 ejects ink onto the first side of the sheet P as shown by the arrow, to record an image. The path switching unit 26 is set to a position for double-sided recording (the position shown by the dashed line in Figure 3A). The process in Figure 10(A) positions the shutter 450 in the open position, and the heating section R2 is set.

[0064] The sheet P is transported toward the drying promotion unit 40. The drying promotion unit 40 starts operating and blows hot air to the sheet P in the heating section R2 (state ST12 in FIG. 8). The hot air accelerates the drying of the sheet P that is wet with ink. Guided by the path switching unit 26, the sheet P is not transported to the drying promotion unit 50 but is transported to the switchback path RT3. Because the heating section R2 is set, hot air is blown to the sheet P even in the switchback path RT3. When the rear end of the sheet P passes the position of the path switching unit 25, the path switching unit 25 is set to a position for double-sided recording. Next, the transport unit 20 transports the sheet P in the opposite direction on the switchback path RT3 (switchback transport).

[0065] Guided by the path switching unit 25, the sheet P is transported to a reverse path RT4 as shown in state ST13 in Fig. 8. Then, the sheet P is returned to the main path RT1 as shown in state ST14 in Fig. 8. The path switching unit 25 is set to a position for single-sided recording (the position shown by the solid line in Fig. 3A). The recording unit 30 ejects ink onto the second side of the sheet P as shown by the arrow to record an image. The subsequent operations are the same as states ST2 to ST4 for single-sided recording.

[0066] The configuration of this embodiment for drying by heating the sheet P can be summarized as follows. The drying promotion unit 50 of this embodiment is configured such that a heating element 51 (heating element 54) is disposed on one side of the transport path RT of the sheet P, and the heating element 51 comes into contact with only one side of the sheet P to heat it. Therefore, although heat is applied to both sides of the sheet P to promote drying, the drying of the one side with which the heating element 51 directly contacts is more promoted. In the case of single-sided recording, the heating element 51 comes into contact with the image recording side of the sheet P.

[0067] In the case of double-sided recording, the heating element 54 faces the second side of the sheet P, and the heating element 51 contacts only the back side, and there is no stage where the heating element 51 contacts the first side of the sheet P. Therefore, in the case of double-sided recording, if other conditions are the same, the drying of the sheet P by the drying promotion unit 50 is promoted more on the second side than on the first side.

[0068] On the other hand, the drying promotion unit 40 of this embodiment is disposed on one side of the transport path RT of the sheet P, and is configured to blow hot air to only one side of the sheet P. Therefore, although the drying of both sides is promoted, the drying is promoted more on the side directly hit by the hot air. In the case of single-sided recording, hot air is blown to the image recording side of the sheet P in the heating section R1.

[0069] In the case of double-sided recording, when an image is recorded on the first side of sheet P, hot air is blown onto the first side in heating section R2, and when an image is recorded on the second side, hot air is blown onto the second side in heating section R1.

[0070] Regarding drying by both drying acceleration units 40 and 50 in the case of double-sided recording, in drying by drying acceleration unit 40, the drying of the first side of sheet P is accelerated more than that of the second side due to the length of the heating section. In drying by drying acceleration unit 50, the drying of the second side of sheet P is accelerated more than that of the first side in terms of the contact surface. Therefore, it is possible to reduce the difference in drying between the front and back sides.

[0071] Second Embodiment In the first embodiment, the difference between single-sided recording and double-sided recording (difference in conveying path) is exemplified as a recording condition that is a criterion for changing the heating section, but the recording condition is not limited to this. For example, the heating section may be changed depending on the amount of ink ejected onto the sheet P. Specifically, when the amount of ink ejected is large, a long heating section may be selected to improve the drying ability, and when the amount of ink ejected is small, a short heating section may be selected. In the example of FIG. 10(A), if it is determined in S3 that the second side of the sheet is not at the stage where an image is to be recorded, it is further determined whether the amount of ink ejected onto the first side is equal to or greater than a threshold value without immediately proceeding to S4. If the amount of ink ejected is equal to or greater than the threshold value, the process proceeds to S4, and if it is less than the threshold value, the process proceeds to S2.

[0072] <Third embodiment> In the first embodiment, regardless of whether the heating section R1 or R2 is set, the driving conditions of the fan 42 and the heating element 43 of the warm air drying unit 40 are not changed, but they may be changed. If these driving conditions are the same, the drying capacity per unit area of ​​the sheet is higher when the heating section R1 is set. Therefore, when the heating section R1 is set, the output of at least one of the fan 42 and the heating element 43 may be reduced. This allows for a reduction in power consumption.

[0073] <Fourth embodiment> The heating element 54 of the drying promotion unit 50 may not be constantly heated, and may stop generating heat during a period when the drying promotion unit 50 is not heating and drying the sheet P. FIG. 10B is a flow chart showing an example of drive control of the heating element 54, and the process in the figure is executed by, for example, the drying control unit 17. To summarize the control contents, the heating element 54 starts generating heat when the sheet reaches the midpoint M1, and stops generating heat when the sheet passes the drying promotion unit 50. However, in the case of double-sided recording, the heating element 54 does not start generating heat even if the sheet reaches the midpoint M1 immediately after the image recording on the first side, but starts generating heat when the sheet reaches the midpoint M1 after the image recording on the second side. Since there is a period during which the heating element 54 stops generating heat before the sheet reaches the drying promotion unit 50, it is possible to reduce power consumption and suppress an increase in the temperature inside the device.

[0074] In S11, it is determined whether the image recording conditions for the sheet to be recorded this time are single-sided recording or double-sided recording. If single-sided recording, proceed to S12, and if double-sided recording, proceed to S16. In S12, it is determined whether the sheet has reached the midpoint M1. This determination is made based on the detection result of the sheet sensor described above. If it is determined that the sheet has reached the midpoint M1, proceed to S13, and if it is determined that the sheet has not yet reached the midpoint M1 or has already reached it, proceed to S14.

[0075] In S13, the heating element 54 is driven to start generating heat. In S14, it is determined whether or not the sheet has passed through the drying acceleration unit 50. This determination is made based on the detection result of the sheet sensor described above. If it is determined that the sheet has passed through the drying acceleration unit 50, the process proceeds to S15, and if it is determined that the sheet has not passed through, the process ends. In S15, the driving of the heating element 54 driven in S14 is stopped, and the heat generation is terminated.

[0076] In S16, in double-sided recording, the recording of the image on the first side of the sheet is completed, and it is determined whether the inversion of the sheet is completed (whether the sheet has passed through the inversion path RT4). This determination is made based on the detection result of the sheet sensor described above. If the inversion of the sheet is completed, proceed to S12, and if not, end the process. As a result, in the case of double-sided recording, an image is recorded on the second side of the sheet, and the heating element 54 stops generating heat until the sheet reaches the midpoint M1.

[0077] <Fifth embodiment> In the first embodiment, the shutter unit 45 is used to change the heating section, but other methods can be adopted. Fig. 11 shows another example of the configuration of the drying promotion unit 40. The illustrated drying promotion unit 40 is provided with a partition wall 46 that divides the internal space of the hollow body 41 into upper and lower spaces. As a configuration corresponding to the fan 42 and the heating element 43 of the first embodiment, independently driven fans 42A and 42B and heating elements 43A and 43B are provided. The fan 42A and the heating element 43A are disposed in the lower space of the internal space of the hollow body 41 divided by the partition wall 46, and the fan 42B and the heating element 43B are disposed in the upper space divided by the partition wall 46.

[0078] When the heating section R1 is set, the fan 42A and the heating element 43A are driven and the fan 42B and the heating element 43B are not driven when drying the sheet. When the heating section R2 is set, the fan 42A and the heating element 43A are driven and the fan 42B and the heating element 43B are also driven when drying the sheet.

[0079] FIG. 12 shows another example of the configuration of the drying promotion unit 40. The illustrated drying promotion unit 40 is provided with independently driven heating elements 43A and 43B as a configuration corresponding to the heating element 43 of the first embodiment. The heating element 43A is arranged in the lower space of the internal space of the hollow body 41, and the heating element 43B is arranged in the upper space. The partition wall 46 as shown in FIG. 11 is not provided, and the fan 42 does not distinguish between the upper and lower spaces. Although the airflow generated in the internal space of the hollow body 41 by the driving of the fan 42 becomes turbulent, a temperature difference can be generated depending on the location in the space depending on whether the heating elements 43A and 43B are driven. If the airflow generated in the internal space of the hollow body 41 by the driving of the fan 42 is configured to be close to laminar, this temperature difference can be generated more clearly.

[0080] When the heating section R1 is set, the fan 42 and the heating element 43A are driven, but the heating element 43B is not driven, when drying the sheet. Hot air is blown out from each outlet hole N and is also blown into the switchback path RT3, but because the heating element 43B is not driven, the hot air blown into the switchback path RT3 has a relatively low temperature. Because the heating element 43B is not driven, it is possible to suppress the waste of power consumption and the rise in temperature inside the device.

[0081] When the heating section R2 is set, the fan 42 and the heating elements 43A and 43B are driven when drying the sheet. Since the heating element 43B is also driven, hot air having the same temperature as the other sections is also sent to the switchback route RT3.

[0082] <Other embodiments> The present invention can also be realized by a process in which a program for realizing one or more functions of the above-mentioned embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0083] The invention is not limited to the above-described embodiments, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0084] 5 recording device, 9 control unit, 20 transport unit, 30 recording unit, 40 drying promotion unit, 45 shutter unit, RT transport path, RT3 switchback path

Claims

1. a conveying means for conveying the medium in a conveying direction along a conveying path including an inversion path for inverting a first surface and a second surface of the medium; a recording means for ejecting ink onto the first surface of the medium that is transported without passing through the reversing path, and for ejecting ink onto the second surface of the medium that is transported through the reversing path; a heating unit that heats the medium in a first region downstream of the recording unit in the transport direction, and heats the medium in a second region downstream of the first region in the transport direction, When the heating means heats the medium in the first region, heating by the heating means is not performed in at least a part of the second region under first recording conditions, and heating by the heating means is performed in the second region under second recording conditions; The heating means blows hot air from a plurality of blowing holes, Among the plurality of blowing holes for heating the medium, the blowing holes in the first region are positioned differently from at least a part of the blowing holes in the second region. A recording device comprising:

2. 2. The recording apparatus according to claim 1, further comprising a second heating unit disposed downstream of the heating unit in the transport direction. A recording device comprising:

3. 2. The recording device according to claim 1, The heating means is Hot air is blown from a plurality of blowing holes onto the first surface of the medium that is transported without passing through the inversion path, and Hot air is blown from the plurality of blowing holes onto the second surface of the medium transported through the inversion path. A recording device comprising:

4. 2. The recording device according to claim 1, the medium is a cut sheet; A recording device comprising:

5. A control method for a recording device including: a transport means for transporting a medium in a transport direction along a transport path including an inversion path for inverting a first side and a second side of the medium; a recording means for ejecting ink onto the first side of the medium transported without passing through the inversion path; and a heating means for heating the medium, the control method comprising: heating the medium by the heating means in a first region downstream of the recording means in the transport direction; heating the medium by the heating means in a second region downstream of the first region in the transport direction; when the medium is heated in the first region by the heating means, heating is not performed by the heating means in at least a part of the second region under first recording conditions, and heating is performed by the heating means in the second region under second recording conditions; The heating means blows hot air from a plurality of blowing holes, Among the plurality of blowing holes for heating the medium, the blowing holes in the first region are positioned differently from at least a part of the blowing holes in the second region. A control method comprising:

6. 6. The control method according to claim 5, wherein the recording apparatus further comprises a second heating unit disposed downstream of the heating unit in the transport direction. A control method comprising:

7. 6. The control method according to claim 5, The heating means is Hot air is blown from a plurality of blowing holes onto the first surface of the medium that is transported without passing through the inversion path, and Hot air is blown from the plurality of blowing holes onto the second surface of the medium transported through the inversion path. A control method comprising:

8. 6. The control method according to claim 5, the medium is a cut sheet; A control method comprising:

Images