Warm air blowing device and inkjet printing device

Abstract

To provide a technique enabling a device that dries a print medium by blowing a warm air thereto to shorten the time required for starting up the device.SOLUTION: A warm air blowing device 30 includes an inner housing 35, an outer housing 32, a first blower fan 36, and a switching device. The inner housing 35 has an inner wall portion 351 that surrounds a heat source 31. The outer housing 32 has an outer wall portion 321 that surrounds the inner wall portion 351. The first blower fan 36 generates a flow of warm air from an inside to an outside of the inner wall portion 351 via an inner nozzle 355 provided on the inner wall portion 351. The switching device can switch between: a warm air mode in which the warm air is sent to a heat storage space between the inner wall portion 351 and the outer wall portion 321 by restricting the warm air from being blown outward via an outer nozzle 325 provided in the outer wall portion 321; and a blowing mode in which the warm air is blown toward a print medium via the outer nozzle 325 by allowing the warm air to blow outward via the outer nozzle 325.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a hot air blowing device that blows hot air onto ink on a print medium, and to an inkjet printing device that has a hot air blowing device.

[0002] Conventionally, there is known a printing device that prints by ejecting ink onto the surface of a long, strip-shaped continuous substrate while transporting the continuous substrate using a plurality of transport rollers or the like. Such a printing device is provided with a drying mechanism that dries the ink ejected onto the continuous substrate while transporting the continuous substrate. Such a drying mechanism is described, for example, in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-035184 Summary of the Invention [Problem to be solved by the invention]

[0004] The hot air drying device (100) of Patent Document 1 dries a paper web (P) by spraying a heating medium from a nozzle (12) onto the surface of the paper web (P) while the paper web (P) travels within the internal space (11) of an air cap (10) (paragraph 0001, Figure 1, etc.). The nozzle (12) is connected to a heating device (20). The heating device (20) generates a heating medium and supplies it to the air cap (10) via a heating medium pipe (1). The heating device (20) may, for example, be one that burns fuel to generate a heat source and functions as a direct heat exchanger that heats gas introduced into the pipe (paragraph 0019).

[0005] The air cap (10) is also formed with an intake port (13) for sucking in the heating medium from the internal space (11). The intake port (13) is connected to the heating device (20) via a circulation pipe (2). The circulation pipe (2) is also provided with a circulation fan (30). The circulation fan (30) sucks the heating medium from the internal space (11) through the intake port (13) and supplies it to the heating device (20) through the circulation pipe (2). This forms a circulation path for the heating medium, and the heating medium that comes into contact with the paper web (P) is collected and used again to dry the paper web (P) (paragraph 0020).

[0006] However, when a heating device that functions as a direct heat exchanger that heats gas is used, it takes a significantly long time for the device to start up after being turned on, etc. Specifically, in the case of such a device, it may take as long as several tens of minutes after being started until it can generate hot air at a predetermined temperature.

[0007] The present invention has been developed in consideration of the above circumstances, and aims to provide a technology that can shorten the time required for a device to start up after being turned on when using a device that dries printing media by blowing warm air. [Means for solving the problem]

[0008] To solve the above problems, the first invention of the present application is a hot air blowing device that blows hot air onto ink on a print medium, and includes a heat source, an inner housing, an inner nozzle, an outer housing, an outer nozzle, a first blower fan, a heat storage space, and a switching device. The heat source generates the hot air by heating gas. The inner housing has an inner wall surrounding the heat source. The inner nozzle is formed on the inner wall at a position facing the print medium so as to blow the hot air from inside to outside the inner wall. The outer housing is provided outside the inner wall and has an outer wall surrounding the inner wall. The outer nozzle is formed on the outer wall at a position facing both the print medium and the inner nozzle so as to blow the hot air from inside to outside the outer wall. The first blower fan generates a flow of the hot air from inside to outside the inner wall via the inner nozzle. The heat storage space is formed between the inner wall and the outer wall. The switching device is capable of switching between a warm air mode and a blowing mode. The warm air mode is a mode in which the warm air blown outward through the inner nozzle is sent to the heat storage space by restricting the warm air from being blown outward through the outer nozzle. The blowing mode is a mode in which the warm air blown outward through the inner nozzle is blown onto the ink on the print medium through the outer nozzle by allowing the warm air to be blown outward through the outer nozzle.

[0009] A second invention of the present application is the hot air blowing device of the first invention, wherein the switching device has a second blower fan and a rotation control unit. The second blower fan generates a flow of hot air in the heat storage space in a direction away from the outer nozzle. The rotation control unit controls the rotation of the first blower fan and the second blower fan. In the warm-up mode, the rotation control unit makes the airflow rate of the first blower fan smaller than the airflow rate of the second blower fan. Furthermore, in the blowing mode, the rotation control unit makes the airflow rate of the first blower fan larger than the airflow rate of the second blower fan.

[0010] A third invention of the present application is the hot air blowing device of the first or second invention, wherein a circulation flow path is formed through which the hot air sent to the heat storage space is supplied again to the inside of the inner wall portion.

[0011] A fourth aspect of the present invention is the hot air blowing device of the first aspect, wherein the switching device includes a shutter plate that can open and close the outer nozzle from outside the outer wall portion, and a shutter movement mechanism that moves the shutter plate back and forth between an open position and a closed position. The shutter movement mechanism moves the shutter plate to the closed position in the warm-air mode and to the open position in the blowing mode.

[0012] The fifth invention of the present application is a hot air blowing device of the fourth invention, wherein the shutter plate covers the outer nozzle from the outside of the outer wall portion when in the closed position, and is spaced apart from the outer nozzle when in the open position.

[0013] A sixth aspect of the present invention is the hot air blowing device of the fourth aspect, wherein the shutter plate includes a fixed plate fixed to the outer wall portion and covering the outer nozzle from outside the outer wall portion, and a sliding plate overlapping the fixed plate and supported slidably relative to the fixed plate. The fixed plate has one or more first through holes penetrating the fixed plate. The sliding plate has one or more second through holes penetrating the sliding plate. When the shutter plate is in the closed position, the first through holes and the second through holes do not communicate with each other, and when the shutter plate is in the open position, the first through holes and the second through holes communicate with each other.

[0014] A seventh aspect of the present invention is the hot air blowing device of the first aspect, wherein the switching device has an on-off valve and a valve on-off mechanism. The on-off valve is provided in the outer nozzle and has an adjustable opening. The valve on-off mechanism switches the on-off valve between an open position and a closed position. In the warm-air mode, the valve on-off mechanism switches the on-off valve to the closed position to close the outer nozzle. In the blowing mode, the valve on-off mechanism switches the on-off valve to the open position to open the outer nozzle.

[0015] The eighth invention of the present application is an inkjet printing device comprising a transport mechanism that transports the printing medium along a predetermined transport path, an ejection head that ejects droplets of the ink onto the surface of the printing medium transported by the transport mechanism, and a hot air blowing device of any one of the first to seventh inventions that blows hot air onto the ink on the printing medium downstream of the ejection head on the transport path. [Effects of the Invention]

[0016] According to the first to eighth aspects of the present invention, when the gas inside the inner housing is at a low temperature, the warm air generated by the heat source can be sent to the heat storage space between the inner wall and the outer wall. That is, the warm air generated by the heat source can be flowed into the heat storage space adjacent to the inner housing. This supports the increase in temperature of the warm air generated inside the inner housing, thereby shortening the time required for the warm air to reach a predetermined temperature. Furthermore, since the entire housing, including the inner and outer wall portions, can be heated, it is possible to prevent the generated warm air from coming into contact with the inner or outer wall portions and decreasing in temperature. Furthermore, after the warm air reaches a predetermined temperature, it can be blown onto the ink on the printing medium through the outer nozzle. This allows the ink on the printing medium to be efficiently heated.

[0017] In particular, according to the second aspect of the present invention, it is possible to switch between the warm-air mode and the spray mode without making the structure around the outer nozzle too complicated.

[0018] In particular, according to the third aspect of the present invention, the warm air can be reused to heat the air more efficiently.

[0019] In particular, according to the fourth and seventh aspects of the present invention, switching between the warm-air mode and the blowing mode can be performed more reliably.

[0020] In particular, according to the fifth aspect of the present invention, the generated hot air can be sent out to the outside of the outer wall portion in the blowing mode without being throttled.

[0021] In particular, according to the sixth invention of the present application, by sliding the sliding plate relative to the fixed plate, the communication between the inner space of the outer housing and the outer space can be established and blocked, thereby making it possible to further miniaturize the switching device. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram conceptually illustrating the configuration of an inkjet printing apparatus according to a first embodiment. [Figure 2] 1 is a perspective view of a hot air blowing device according to a first embodiment. [Figure 3] 1 is a cross-sectional view of a hot air blowing device according to a first embodiment. [Figure 4] 1 is a partially enlarged cross-sectional view of a hot air blowing device according to a first embodiment. [Figure 5] 2 is a block diagram showing connections between a control unit and each unit of an inkjet printing apparatus according to the first embodiment. FIG. [Figure 6] 4 is a flowchart showing a procedure for starting up the hot air blowing device of the first embodiment. [Figure 7] FIG. 10 is a cross-sectional view of a hot air blowing device according to a second embodiment. [Figure 8] FIG. 10 is a partially enlarged cross-sectional view of a hot air blowing device according to a first modified example. [Figure 9] FIG. 10 is a partially enlarged cross-sectional view of a hot air blowing device according to a second modified example. [Figure 10] FIG. 10 is a partially enlarged cross-sectional view of a hot air blowing device according to a third modified example. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the components described in these embodiments are merely examples and are not intended to limit the scope of the present invention. Furthermore, in the drawings, the dimensions and numbers of each part may be exaggerated or simplified as necessary to facilitate understanding.

[0024] 1. First Embodiment <1-1. Configuration of inkjet printing device> FIG. 1 is a conceptual diagram illustrating the configuration of an inkjet printing apparatus 1 according to a first embodiment of the present invention. This inkjet printing apparatus 1 is an inkjet printer that records characters and images on the surface of a long, strip-shaped continuous substrate 9 by ejecting droplets of aqueous ink from multiple ejection heads 21 toward the continuous substrate 9 while transporting the continuous substrate 9. However, the long, strip-shaped continuous substrate 9 is merely one example of a printing medium. The printing medium may be a plastic film, or a substrate, release paper, sticker, or label made of resin, paper, cardboard, metal foil, or glass. The printing medium may also be a layered substrate in which multiple media made of the same or different materials are layered. In other words, the inkjet printing apparatus 1 may be any device that ejects ink onto a printing medium to perform printing.

[0025] As shown in FIG. 1, the inkjet printing apparatus 1 includes a transport mechanism 10, a printing mechanism 20, a hot air blowing device 30, and a control unit 90.

[0026] The transport mechanism 10 transports the continuous base material 9 in a transport direction along a predetermined transport path TR, which is parallel to the longitudinal direction of the continuous base material 9. The transport mechanism 10 transports the continuous base material 9 using a roll-to-roll method. The transport mechanism 10 includes a feed roller 11, multiple transport rollers 12, a winding roller 13, and a rotation drive unit 15. The feed roller 11, the multiple transport rollers 12, and the winding roller 13 are rotatable about horizontal axes extending perpendicular to the transport direction. The rotation drive unit 15 rotates the winding roller 13 by driving a motor or the like (not shown). The rotation drive unit 15 may also rotate rollers other than the winding roller 13 (such as the transport roller 12).

[0027] The feed roller 11 pays out the continuous base material 9 wound in a roll. Each transport roller 12 is arranged along the transport path TR of the continuous base material 9. The multiple transport rollers 12 support the continuous base material 9 fed from the feed roller 11 on the predetermined transport path TR. The winding roller 13 winds up the continuous base material 9 that has passed through the transport path TR into a roll. In FIG. 1, the transport direction of the continuous base material 9 along the transport path TR is indicated appropriately by an arrow.

[0028] The printing mechanism 20 has a plurality of (four in this embodiment) ejection heads 21. Each of the four ejection heads 21 has a printable width greater than the size of the width direction Dw of the continuous substrate 9. Here, the "width direction Dw" refers to a direction perpendicular and substantially horizontal to the transport direction, and indicates a direction perpendicular to the paper surface of FIG. 1. The four ejection heads 21 have the same structure. The four ejection heads 21 are arranged in sequence along the transport path TR at intervals from each other in the transport direction. Each of the four ejection heads 21 ejects ink droplets from a plurality of nozzles (not shown) toward the surface (top surface) of the continuous substrate 9 transported by the transport mechanism 10. The four ejection heads 21 eject ink droplets of each color, K (black), C (cyan), M (magenta), and Y (yellow), in sequence downstream of the transport path TR to record a single-color image on the surface (top surface) of the continuous substrate 9. The droplets of K, C, M, and Y inks become the color components of a color image, and a multicolor image is formed on the upper surface of the continuous substrate 9 by superimposing the four single-color images.

[0029] The hot air blowing device 30 is disposed downstream of the printing mechanism 20 in the transport direction. The hot air blowing device 30 is a drying mechanism that blows hot air onto the continuous substrate 9 onto which ink droplets have been ejected by the four ejection heads 21 while being transported by the transport mechanism 10. The hot air blowing device 30 blows hot air onto the continuous substrate 9 downstream of the four ejection heads 21 along the transport path TR. The hot air blowing device 30 also blows hot air onto the ink on the continuous substrate 9, thereby drying the ink ejected onto the upper surface of the continuous substrate 9 and fixing it to the continuous substrate 9. Note that the hot air blowing device 30 of this embodiment is disposed above the transport path TR of the continuous substrate 9. However, the position at which the hot air blowing device 30 is disposed is not limited thereto.

[0030] FIG. 2 is a perspective view of the hot air blowing device 30. For ease of understanding, FIG. 2 illustrates a side end surface 322 (described later) spaced apart from an outer wall 321 (described later). FIG. 2 also omits a first blower fan 36, second blower fans 371 and 372, and a temperature sensor 38 (described later). FIG. 3 is a cross-sectional view of the hot air blowing device 30 cut in a direction perpendicular to the width direction Dw. Hatching and other elements are omitted in FIG. 3 to avoid overlying the drawing. The hot air blowing device 30 is disposed above the continuous substrate 9, spanning the entire width direction Dw of the continuous substrate 9. In the following description of the hot air blowing device 30, the horizontal direction perpendicular to the width direction Dw of the continuous substrate 9 is referred to as the "horizontal direction Dl." The horizontal direction Dl substantially coincides with the conveyance direction of the continuous substrate 9 below the hot air blowing device 30. As shown in Figures 2 and 3, the hot air blowing device 30 has a heat source 31, an outer housing 32, a first partition plate 33, a second partition plate 34, an inner housing 35, a first blower fan 36, second blower fans 371, 372, and a temperature sensor 38.

[0031] The heat source 31 is a so-called sheathed heater, and includes a nichrome wire, which is a heating element covered with a metal pipe. The heat source 31 is located at a lower portion near the center of the horizontal direction Dl in the space inside the outer housing 32. The heat source 31 also extends along the width direction Dw. The nichrome wire is a spiral resistor and is connected to a power source via wiring and an on / off circuit (not shown). When energized, the nichrome wire generates heat as a current flows through it, warming the gas (e.g., air) that comes into contact with the nichrome wire. This allows the heat source 31 to generate warm air (including hot air) at a temperature of several tens to several hundred degrees Celsius. That is, the heat source 31 generates warm air by heating the nearby gas. As described below, the warm air generated by the heat source 31 is supplied toward the continuous substrate 9 being transported near the hot air blowing device 30. As a result, the ink ejected onto the upper surface of the continuous substrate 9 can be dried.

[0032] The outer housing 32 is a member that forms the outer frame of the hot air blowing device 30. The outer housing 32 has an outer wall portion 321, a first end surface portion 322, and an second end surface portion 323. The outer wall portion 321 expands in a cylindrical shape along the width direction Dw. A heat insulating material or the like is attached to the outside of the outer wall portion 321 to insulate it from the outside air. The outer wall portion 321 is disposed so as to span the entire width direction Dw of the continuous substrate 9 transported below the hot air blowing device 30. The outer wall portion 321 is disposed outside an inner wall portion 351 (described later) and surrounds the inner wall portion 351. An outer converging portion 324 is formed at the bottom of the outer wall portion 321. When the outer housing 32 is viewed from one side or the other side in the width direction Dw, the outer converging portion 324 is a funnel-shaped portion that gradually converges downward.

[0033] An outer nozzle 325 is formed at the lower end of the outer converging portion 324 of the outer wall portion 321. The outer nozzle 325 is an opening for blowing hot air from the inside to the outside of the outer wall portion 321. The outer nozzle 325 is formed at a position on the outer wall portion 321 facing the continuous base material 9 and an inner nozzle 355 (described later). The outer nozzle 325 has a hot air blowing width that is larger than the size of the width direction Dw of the continuous base material 9 transported below the hot air blowing device 30.

[0034] The one-side end surface portion 322 is a member that covers one end of the outer wall portion 321 in the width direction Dw. A first exhaust opening 391 and a second exhaust opening 392 are formed in the one-side end surface portion 322. The first exhaust opening 391 is connected to a one-side heat storage space 52 (described later) and is an opening for discharging gas from the one-side heat storage space 52 to the outside of the outer housing 32. The second exhaust opening 392 is connected to a second-side heat storage space 53 (described later) and is an opening for discharging gas from the second-side heat storage space 53 to the outside of the outer housing 32. The first exhaust opening 391 and the second exhaust opening 392 are normally closed. The first exhaust opening 391 and the second exhaust opening 392 are opened as appropriate when, for example, the amount of gas in the one-side heat storage space 52 and the second-side heat storage space 53 becomes excessively large.

[0035] The other-side end surface portion 323 is a member that covers the other end of the outer wall portion 321 in the width direction Dw. An intake opening 390 is formed in the other-side end surface portion 323. The intake opening 390 communicates with an upper space 326, which will be described later, and is an opening for taking in gas from the outside to the inside of the outer housing 32. The intake opening 390 is normally open.

[0036] The first partition plate 33 is a plate-shaped member extending in a substantially horizontal direction. The first partition plate 33 extends over the entire space inside the outer housing 32 in the width direction Dw and the lateral direction Dl. Both ends of the first partition plate 33 in the width direction Dw are fixed to the one-side end surface portion 322 and the other-side end surface portion 323, respectively. Furthermore, both ends of the first partition plate 33 in the lateral direction Dl are fixed to the outer wall portion 321. As a result, an upper space 326 is formed inside the outer housing 32, located above the first partition plate 33.

[0037] A plurality of through holes 330 are provided in the first partition plate 33 at a position above the heat source 31. Each of the plurality of through holes 330 passes through the first partition plate 33 in the up-down direction (thickness direction). Furthermore, a plurality of through holes 331 are provided in the first partition plate 33 at positions above one-side heat storage space 52 and another-side heat storage space 53 (described later). Each of the plurality of through holes 331 passes through the first partition plate 33 in the up-down direction (thickness direction). The intake opening 390 is formed above the position at which the first partition plate 33 is fixed on the other-side end surface portion 323. That is, the intake opening 390 communicates with the upper space 326.

[0038] The second partition plate 34 is a plate-shaped member extending in a substantially horizontal direction below the first partition plate 33. The second partition plate 34 extends in a substantially horizontal direction at a position spaced downward from the first partition plate 33 by a gap. The second partition plate 34 also extends across the entire width direction Dw of the space inside the outer housing 32. Both ends of the second partition plate 34 in the width direction Dw are fixed to the one-side end surface portion 322 and the other-side end surface portion 323, respectively. The second partition plate 34 is also located near the center of the space inside the outer housing 32 in the horizontal direction Dl. Both ends of the second partition plate 34 in the horizontal direction Dl are fixed to inner wall portions 351, which will be described later.

[0039] As a result, a rectifying space 327 is formed near the center in the horizontal direction Dl inside the outer housing 32, located below the first partition plate 33 and above the second partition plate 34. Furthermore, a plurality of through holes 340 are provided in the second partition plate 34 at positions above the heat source 31. Each of the plurality of through holes 340 penetrates the second partition plate 34 in the up-down direction (thickness direction).

[0040] The inner housing 35 is a member provided inside the outer housing 32. The inner housing 35 has an inner wall portion 351 and inner mounting portions 352 and 353. The inner wall portion 351 extends along the width direction Dw. When the inner housing 35 is viewed from one side or the other side in the width direction Dw, the inner wall portion 351 has a substantially U-shape. The inner wall portion 351 is made of a material with high thermal conductivity, such as aluminum or black anodized aluminum. The thickness of the inner wall portion 351 is thinner than the thickness of the outer wall portion 321. The inner wall portion 351 is disposed so as to span the entire width direction Dw of the continuous substrate 9 transported below the hot air blowing device 30. When the inner housing 35 is viewed from one side or the other side in the width direction Dw, the heat source 31 is located inside the substantially U-shape of the inner wall portion 351. That is, the inner wall portion 351 surrounds the heat source 31. An inner converging portion 354 is formed at the lower part of the inner wall portion 351. The inner converging portion 354 is a funnel-shaped portion that gradually converges downward when the inner housing 35 is viewed from one side or the other side in the width direction Dw.

[0041] An inner nozzle 355 is formed at the lower end of the inner converging portion 354 in the inner wall portion 351. The inner nozzle 355 is an opening for blowing hot air from the inside to the outside of the inner wall portion 351. The inner nozzle 355 is formed in a position on the inner wall portion 351 facing the continuous base material 9 and the outer nozzle 325. The inner nozzle 355 has a hot air blowing width that is larger than the size in the width direction Dw of the continuous base material 9 transported below the hot air blowing device 30.

[0042] The inner mounting portions 352, 353 are each a portion extending substantially horizontally from an upper end of the inner wall portion 351 in a direction away from the inner wall portion 351. The inner mounting portion 352 extends from an upper end of the inner wall portion 351 on one side in the lateral direction Dl to one side in the lateral direction Dl. The inner mounting portion 353 extends from an upper end of the inner wall portion 351 on the other side in the lateral direction Dl to the other side in the lateral direction Dl. The inner mounting portions 352, 353 are each fixed to the underside of the first partition plate 33 by, for example, screws. However, the inner mounting portions 352, 353 are designed not to block the multiple through holes 331 of the first partition plate 33. For example, the inner mounting portions 352, 353 are provided with gaps, through holes, or the like (not shown) at positions that overlap the multiple through holes 331 of the first partition plate 33 in the vertical direction.

[0043] A central space 51 is formed below the second partition plate 34 inside the inner casing 35. The central space 51 is a space located near the center of the outer casing 32 in the horizontal direction Dl. A heat source 31 is disposed in the central space 51. A first heat storage space 52 is formed below the first partition plate 33 and on one side of the flow straightening space 327 and the central space 51 in the horizontal direction Dl. A second heat storage space 53 is formed below the first partition plate 33 and on the other side of the flow straightening space 327 and the central space 51 in the horizontal direction Dl. The first heat storage space 52 and the second heat storage space 53 each correspond to a "heat storage space" according to the present invention. As shown in FIG. 3 , the "heat storage space" according to the present invention is formed between an inner wall portion 351 and an outer wall portion 321.

[0044] Figure 4 is a partial enlarged view of the vicinity of the outer nozzle 325 and the inner nozzle 355 in Figure 3. As shown in Figures 3 and 4, the width of the narrowest part of the one-side heat storage space 52 and the width of the narrowest part of the other-side heat storage space 53 are each greater than the width of the narrowest part of the inner nozzle 355. In other words, the flow path resistance of the flow paths Fb1, Fb2 through which the gas blown out to the outside of the inner nozzle 355 flows toward the one-side heat storage space 52 or the other-side heat storage space 53 is smaller than the flow path resistance of the flow path Fa of the gas flowing from the inside to the outside of the inner nozzle 355.

[0045] Furthermore, the width of the narrowest part of the outer nozzle 325 is greater than the width of the narrowest part of the one-side heat storage space 52 and the width of the narrowest part of the other-side heat storage space 53. In other words, the flow path resistance of the gas flow path Fc from the inside to the outside of the outer nozzle 325 is smaller than the flow path resistance of the gas flow paths Fb1, Fb2 of the gas blown out of the inner nozzle 355 toward the one-side heat storage space 52 or the other-side heat storage space 53.

[0046] A first blower fan 36 is disposed above the heat source 31 in the central space 51. The first blower fan 36 uses an axial fan motor that rotates an impeller using the driving force of a motor (not shown) to generate an airflow from above to below the central space 51. As the first blower fan 36 rotates, an airflow is generated that flows toward the outside of the inner housing 35 via the intake opening 390, the upper space 326, the through-hole 330 in the first partition plate 33, the rectifying space 327, the through-hole 340 in the second partition plate 34, the central space 51, the heat source 31 in the central space 51, and the inner nozzle 355. That is, the first blower fan 36 generates a flow of warm air that flows from the inside to the outside of the inner wall portion 351 via the inner nozzle 355.

[0047] In this way, the airflow flows through the through-holes 330 of the first partition plate 33, the rectifying space 327, and the through-holes 340 of the second partition plate 34, and is rectified so that the airflow flows substantially vertically downward (substantially downward in the up-down direction). The airflow comes into contact with the heat source 31 in the central space 51 and is heated, thereby becoming hot air. However, the first blower fan 36 may be provided in the upper space 326 or the rectifying space 327. The first blower fan 36 may also be provided outside the outer housing 32, near the intake opening 390.

[0048] A second blower fan 371 is disposed in the one-side heat storage space 52. The second blower fan 371 uses an axial fan motor that rotates an impeller using the driving force of a motor (not shown) to generate an airflow from below to above the one-side heat storage space 52. As the second blower fan 371 rotates, an airflow is generated from the one-side heat storage space 52 through the through-holes 331 of the first partition plate 33 toward the upper space 326. That is, the second blower fan 371 generates a flow of warm air in the one-side heat storage space 52 that is directed away from the outer nozzles 325. The airflow that reaches the upper space 326 merges with the airflow generated by the first blower fan 36 and flows again toward the central space 51.

[0049] A second blower fan 372 is disposed in the other-side heat storage space 53. The second blower fan 372 uses an axial fan motor that rotates an impeller using the driving force of a motor (not shown) to generate an airflow from below to above the other-side heat storage space 53. When the second blower fan 372 rotates, an airflow is generated from the other-side heat storage space 53 toward the upper space 326 through the through-holes 331 of the first partition plate 33. That is, the second blower fan 372 generates a flow of warm air in the other-side heat storage space 53, directed away from the outer nozzle 325. In other words, the second blower fans 371, 372 generate a flow of warm air in the "heat storage space" of the present invention, directed away from the outer nozzle 325. The airflow that reaches the upper space 326 merges with the airflow generated by the first blower fan 36 and then flows back toward the central space 51.

[0050] That is, in this embodiment, a circulation flow path is formed in which the warm air sent to the one-side heat storage space 52 and the other-side heat storage space 53 is supplied again to the inside of the inner wall portion 351. In this way, in this embodiment, the heated warm air is reused, so that the gas (air) in the inner housing 35 can be warmed more efficiently.

[0051] A temperature sensor 38 is mounted near the outer nozzle 325 of the outer housing 32. The temperature sensor 38 detects the temperature of the hot air flowing near the outer nozzle 325. The temperature sensor 38 is also electrically connected to the control unit 90. The temperature sensor 38 outputs data related to the detection result of the temperature of the hot air to the control unit 90. However, the position where the temperature sensor 38 is mounted is not limited to this.

[0052] The rotation speeds of the first blower fan 36 and the second blower fans 371, 372 are adjustable. The second blower fans 371, 372 can also rotate in opposite directions to generate airflows toward the outer nozzles 325 in the one-side heat storage space 52 and the other-side heat storage space 53. The first blower fan 36 and the second blower fans 371, 372 are electrically connected to the control unit 90. The control unit 90 adjusts the rotation speeds of the first blower fan 36 and the second blower fans 371, 372 based on data input from the temperature sensor 38.

[0053] Next, the control unit 90 will be described. The control unit 90 is an information processing device for controlling each unit of the inkjet printing apparatus 1. FIG. 5 is a block diagram showing the connection between the control unit 90 and each unit of the inkjet printing apparatus 1. As conceptually shown in FIG. 5, the control unit 90 has a processor 91 such as a CPU, a memory 92 such as RAM, and a storage unit 93 such as a hard disk drive. The storage unit 93 stores a computer program 90P for executing a printing process while transporting the continuous base material 9 and for drying the continuous base material 9 onto which ink has been ejected.

[0054] 5, the control unit 90 is communicatively connected to the transport mechanism 10, the four ejection heads 21 of the printing mechanism 20, the heat source 31 of the hot air blowing device 30, the first blower fan 36, the second blower fans 371 and 372, and the temperature sensor 38. The processor 91 of the control unit 90 controls the operation of each of these units in accordance with a computer program 90P. This allows the transport and printing process of the continuous base material 9 to proceed, and the drying process of the continuous base material 9 onto which the ink has been ejected to proceed.

[0055] <1-2. Procedure for starting up the hot air blower and performing the drying process> Next, a procedure for starting up the hot air blowing device 30 from a low-temperature state and performing a drying process on the continuous substrate 9 onto which ink has been ejected will be described. When the hot air blowing device 30 is in a low-temperature state, the inner housing 35 is also typically at a low temperature. When the inner housing 35 is at a low temperature, even if the power source connected to the heat source 31 is turned on, the hot air blowing device 30 cannot immediately blow out hot air at a temperature high enough to dry the continuous substrate 9. Therefore, in this embodiment, before starting the drying process on the continuous substrate 9, a start-up process is performed to transition the inner housing 35 and outer housing 32 of the hot air blowing device 30 from a low-temperature state to a high-temperature state. Figure 6 is a flowchart showing the procedure for starting up the hot air blowing device 30.

[0056] When starting up the hot air blowing device 30, the control unit 90 sets the device to a "warm-up mode" and turns on the power of the heat source 31 to energize the internal nichrome wire. The control unit 90 also drives the first blower fan 36 and the second blower fans 371 and 372 (step S1). At this time, the airflow rate of the first blower fan 36 is set to be smaller than that of the second blower fans 371 and 372. More specifically, the control unit 90 adjusts the rotation speeds of the first blower fan 36, the second blower fan 371, and the second blower fan 372 so that the sum of the airflow rates of the second blower fan 371 and the second blower fan 372 is greater than that of the first blower fan 36. The control unit 90 also turns on the power of the temperature sensor 38.

[0057] As a result, first, the gas in the central space 51 inside the inner housing 35 comes into contact with the nichrome wire of the heat source 31 and is slightly heated. Then, the slightly heated warm air in the central space 51 is blown out of the inner housing 35 from the inner nozzle 355 by the airflow of the first blower fan 36. Here, as described above, the flow path resistance of the flow paths Fb1, Fb2 through which the gas blown out of the inner nozzle 355 flows toward the one-side heat storage space 52 or the other-side heat storage space 53 is smaller than the flow path resistance of the flow path Fa of the gas flowing from the inside to the outside of the inner nozzle 355. Furthermore, the second blower fans 371 and 372 work together to blow a larger amount of gas than the first blower fan 36, thereby generating gas flows in the one-side heat storage space 52 and the other-side heat storage space 53 that flow in a direction away from the outer nozzle 325. As a result, the warm air that has been slightly heated by contact with the nichrome wire of the heat source 31 is blown out to the outside of the inner housing 35 through the inner nozzle 355, and then flows toward the one side heat storage space 52 or the other side heat storage space 53 without flowing back.

[0058] As described above, in this embodiment, the warm air blown outward through the inner nozzle 355 can be sent to the one-side heat storage space 52 or the other-side heat storage space 53. That is, when the gas inside the inner casing 35 is low temperature, the warm air generated by the heat source 31 can be sent to the one-side heat storage space 52 or the other-side heat storage space 53 between the inner wall portion 351 and the outer wall portion 321. In other words, the warm air generated by the heat source 31 can be caused to flow into the one-side heat storage space 52 or the other-side heat storage space 53 adjacent to the inner casing 35. Furthermore, the warm air blown outward through the inner nozzle 355 can be prevented from flowing back or being blown out of the outer casing 32 through the outer nozzle 325. This makes it possible to heat the entire inner casing 35, including the inner wall portion 351, and the outer casing 32, including the outer wall portion 321, thereby supporting the temperature rise of the warm air generated inside the inner casing 35. As a result, the time required for the warm air to reach a predetermined temperature can be shortened. Furthermore, it is possible to prevent the generated hot air from coming into contact with the inner wall portion 351 or the outer wall portion 321 and being cooled.

[0059] Next, the temperature sensor 38 begins to detect the temperature of the hot air blown outward through the inner nozzle 355. The control unit 90 confirms that the temperature of the hot air is gradually increasing based on the data input from the temperature sensor 38. The control unit 90 then determines whether the temperature of the hot air, based on the detection result by the temperature sensor 38, is equal to or greater than a value (a predetermined lower limit) required to dry the ink (step S2). If the detection result by the temperature sensor 38 is less than the predetermined lower limit (step S2: No), the control unit 90 determines that the temperature of the hot air has not yet risen sufficiently, and executes step S2 again.

[0060] On the other hand, if the detection result by the temperature sensor 38 is equal to or higher than the value (predetermined lower limit) required to dry the ink (step S2: YES), the control unit 90 determines that the temperature of the hot air has risen sufficiently and determines that startup of the hot air blowing device 30 has been completed (step S3). Then, transport of the continuous base material 9 and printing processing are started. The control unit 90 sets the airflow rate of the first blower fan 36 to be greater than the airflow rates of the second blower fans 371 and 372 in the "blowing mode." More specifically, the control unit 90 adjusts the rotation speed of the first blower fan 36, the rotation speed of the second blower fan 371, and the rotation speed of the second blower fan 372 so that the airflow rate of the first blower fan 36 is greater than the sum of the airflow rates of the second blower fan 371 and the second blower fan 372.

[0061] As described above, the flow path resistance of the gas flow path Fc from the inside to the outside of the outer nozzle 325 is smaller than the flow path resistance of the gas flow paths Fb1, Fb2 through which the gas blown out of the inner nozzle 355 flows toward the one heat storage space 52 or the other heat storage space 53. The second blower fans 371 and 372 cooperate to blow a smaller amount of gas than the first blower fan 36, thereby generating a flow of warm air blowing outward through the outer nozzle 325. That is, it is possible to allow warm air to be blown outward through the outer nozzle 325. As a result, the warm air blown outward through the inner nozzle 355 can be further sent outward through the outer nozzle 325 to the outside of the outer housing 32 and sprayed onto the ink on the continuous substrate 9 being transported below the warm air blowing device 30. Note that in the "blowing mode," the rotation of the second blower fans 371, 372 may be stopped. In the "blowing mode", the second blower fans 371, 372 may be rotated in opposite directions to generate air currents in the first heat storage space 52 and the second heat storage space 53 toward the outer nozzle 325.

[0062] The control unit 90 also operates the transport mechanism 10 to transport the continuous base material 9 in the longitudinal direction along a predetermined transport path TR, while controlling the four ejection heads 21 to eject ink droplets onto the surface (upper surface) of the continuous base material 9. This records an image on the surface of the continuous base material 9. Thereafter, when the continuous base material 9 arrives below the hot air blowing device 30 located downstream of the printing mechanism 20, the ink is dried by the hot air blown out from the outer nozzles 325 and fixed to the surface of the continuous base material 9. As a result, the drying process of the image recorded on the surface of the continuous base material 9 is completed.

[0063] As described above, the control unit 90 of this embodiment functions as a "rotation control unit" that controls the rotation of the first blower fan 36 and the second blower fans 371, 372. In this embodiment, the "rotation control unit" and the second blower fans 371, 372 form a "switching device" that can switch between the "warm air mode" and the "blowing mode." This allows switching between the "warm air mode" and the "blowing mode" without significantly complicating the structure around the outer nozzle 325. In this embodiment, two second blower fans are provided (second blower fans 371, 372), and in the "warm air mode," the sum of the airflow rates of these two second blower fans 371, 372 is controlled to be greater than the airflow rate of the first blower fan 36, and in the "blowing mode," the sum of the airflow rates of these two second blower fans 371, 372 is controlled to be smaller than the airflow rate of the first blower fan 36. However, the number of second blower fans is not limited to two and may be, for example, one. In this case, the airflow rate of the one second blower fan is controlled to be greater than the airflow rate of the first blower fan 36 in the "warm-up mode," and the airflow rate of the one second blower fan is controlled to be smaller than the airflow rate of the first blower fan 36 in the "blowing mode."

[0064] 2. Second Embodiment Next, the configuration of an inkjet printing apparatus 1 according to a second embodiment of the present invention will be described. The following description will focus on differences from the first embodiment, and the same reference numerals will be used to describe parts equivalent to those in the first embodiment, with some overlapping description omitted. Figure 7 is a cross-sectional view of the hot air blowing device 30B according to this embodiment, cut in a direction perpendicular to the width direction Dw.

[0065] As shown in FIG. 7 , the hot air blowing device 30B of this embodiment does not use the second blower fans 371, 372 provided in the hot air blowing device 30 of the first embodiment. The first blower fan 36 is provided and generates a flow of hot air from the inside to the outside of the inner wall portion 351 via the inner nozzle 355. In the hot air blowing device 30B of this embodiment, instead of the second blower fans 371, 372, a shutter plate 61B and a shutter movement mechanism (not shown) are disposed near the outer nozzle 325 of the outer housing 32. The shutter plate 61B extends in a plate shape along the outer nozzle 325 below the outer nozzle 325. The shutter plate 61B is also larger than the outer nozzle 325. This allows the shutter plate 61B to close the outer nozzle 325 from below without any gaps when in the closed position Pc. That is, the shutter plate 61B covers the outer nozzle 325 from the outside of the outer wall portion 321 when it is in the closed position Pc.

[0066] The shutter movement mechanism uses the driving force of a cylinder (not shown) or the like to reciprocate the shutter plate 61B between a closed position Pc where the shutter plate 61B tightly closes the outer nozzle 325 from below, and an open position Po where the shutter plate 61B opens the outer nozzle 325. When the shutter plate 61B is in the open position Po, it is spaced apart from the outer nozzle 325. Note that in FIG. 7, the shutter plate 61B in the open position Po is shown by a dashed line. This allows the shutter plate 61B to open and close the outer nozzle 325 from outside the outer wall portion 321.

[0067] The shutter movement mechanism is also electrically connected to the control unit 90. The control unit 90 drives the shutter movement mechanism to move the shutter plate 61B based on data input from the temperature sensor 38. More specifically, the shutter movement mechanism moves the shutter plate 61B to the closed position Pc in the "warm air mode." This prevents the warm air blown outward through the inner nozzle 355 from being further blown outward through the outer nozzle 325. As a result, the shutter movement mechanism can send the warm air blown outward through the inner nozzle 355 to the one heat storage space 52 or the other heat storage space 53.

[0068] As in the first embodiment, in the "warm air mode," the warm air blown outward through the inner nozzle 355 can be sent to the one-side heat storage space 52 or the other-side heat storage space 53. That is, when the gas inside the inner casing 35 is at a low temperature, the warm air generated by the heat source 31 can be sent to the one-side heat storage space 52 or the other-side heat storage space 53 between the inner wall portion 351 and the outer wall portion 321. This makes it possible to heat the entire inner casing 35, including the inner wall portion 351, and the entire outer casing 32, including the outer wall portion 321, thereby supporting the increase in temperature of the warm air generated inside the inner casing 35. As a result, the time required for the warm air to reach a predetermined temperature can be shortened. Furthermore, the generated warm air can be prevented from coming into contact with the inner wall portion 351 or the outer wall portion 321 and decreasing in temperature.

[0069] The shutter movement mechanism also sets the "blowing mode" and moves the shutter plate 61B to the open position Po. This allows the shutter movement mechanism to allow the hot air blown outward through the inner nozzle 355 to be further blown outward through the outer nozzle 325. As a result, the hot air can be blown through the outer nozzle 325 onto the ink on the continuous substrate 9 being transported below the hot air blowing device 30.

[0070] In this embodiment, the shutter plate 61B and the shutter movement mechanism constitute a "switching device" that can switch between the "warm air mode" and the "spray mode." This configuration also ensures reliable switching between the "warm air mode" and the "spray mode." In this embodiment, when the shutter plate 61B is in the open position Po, the outer nozzle 325 is fully opened. This allows the warm air to be sent out of the outer wall portion 321 without being throttled in the "spray mode."

[0071] <3. Modifications> Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments.

[0072] <3-1. First modified example> 8 is a partially enlarged cross-sectional view of the vicinity of the outer nozzle 325 and inner nozzle 355 of a hot air blowing device 30C according to a first modified example. This modified example relates to a modified shutter plate 61B of the second embodiment. As shown in FIG. 8, in the hot air blowing device 30C according to this modified example, the shutter plate 61C has a fixed plate 611C and a sliding plate 612C.

[0073] The fixed plate 611C is fixed to the outer wall portion 321 and covers the outer nozzle 325 from the outside of the outer wall portion 321. The fixed plate 611C has one or more first through holes 613C. The one or more first through holes 613C each penetrate the fixed plate 611C in the direction of the flow path Fa of the outer nozzle 325 (see FIG. 4). At least a portion of the one or more first through holes 613C communicates with the outer nozzle 325. The slide plate 612C overlaps the fixed plate 611C and is supported slidably relative to the fixed plate 611C using a driving force of a cylinder (not shown) or the like. The slide plate 612C also has one or more second through holes 614C. The one or more second through holes 614C each penetrate the slide plate 612C in the direction of the flow path Fa of the outer nozzle 325 (see FIG. 4).

[0074] When the shutter plate 61C is in the open position Po, the first through-hole 613C of the fixed plate 611C and the second through-hole 614C of the slide plate 612C overlap in the direction of the flow path Fa of the outer nozzle 325 (see FIG. 4). As a result, when the shutter plate 61C is in the open position Po, the first through-hole 613C and the second through-hole 614C communicate with each other. On the other hand, when the shutter plate 61C is in the closed position Pc, the first through-hole 613C of the fixed plate 611C and the second through-hole 614C of the slide plate 612C do not overlap in the direction of the flow path Fa of the outer nozzle 325 (see FIG. 4). As a result, when the shutter plate 61C is in the closed position Pc, the first through-hole 613C and the second through-hole 614C do not communicate with each other.

[0075] In this modified example, the shutter movement mechanism slides the sliding plate 612C of the shutter plate 61C to the closed position Pc in the "warm air mode." This causes the shutter movement mechanism to block the warm air blown outward through the inner nozzle 355 from being further blown outward through the outer nozzle 325. As a result, the shutter movement mechanism can send the warm air blown outward through the inner nozzle 355 to the one heat storage space 52 or the other heat storage space 53.

[0076] Furthermore, the shutter movement mechanism slides the slide plate 612C of the shutter plate 61C to the open position Po in "blowing mode." This allows the shutter movement mechanism to allow the hot air blown outward through the inner nozzle 355 to be further blown outward through the outer nozzle 325. As a result, the hot air can be blown through the outer nozzle 325 onto the ink on the continuous substrate 9 being transported below the hot air blowing device 30.

[0077] In this manner, in this modification, by sliding slide plate 612C relative to fixed plate 611C, it is possible to establish or block communication between the space inside and the space outside outer housing 32. As a result, it is possible to further miniaturize the "switching device" for switching between the "warm air mode" and the "spray mode."

[0078] <3-2. Second modified example> Fig. 9 is a partially enlarged cross-sectional view of the vicinity of the outer nozzle 325 and inner nozzle 355 of a hot air blowing device 30D according to a second modified example. As shown in Fig. 9, the hot air blowing device 30D of this embodiment does not use the second blower fans 371, 372 that were provided in the hot air blowing device 30 of the first embodiment. However, the first blower fan 36 is provided and generates a flow of hot air from the inside to the outside of the inner wall portion 351 via the inner nozzle 355. In the hot air blowing device 30D of this embodiment, instead of the second blower fans 371, 372, an opening / closing valve 63D and a valve opening / closing mechanism (not shown) are provided in the outer nozzle 325.

[0079] The opening degree of the on-off valve 63D is adjustable. When the on-off valve 63D is in the closed position, it closes the outer nozzle 325. On the other hand, when the on-off valve 63D is in the open position, it opens the outer nozzle 325. In FIG. 9, the on-off valve 63D in the closed position is indicated by a solid line, and the on-off valve 63D in the open position is indicated by a dashed line. The valve on-off mechanism uses the driving force of a motor (not shown) or the like to move the on-off valve 63D between a closed position where the outer nozzle 325 is closed and an open position where the outer nozzle 325 is opened. The valve on-off mechanism is electrically connected to the control unit 90. The control unit 90 drives the valve on-off mechanism based on data input from the temperature sensor 38 to switch the on-off valve 63D between the open position and the closed position.

[0080] More specifically, in the "warm air mode," the valve opening / closing mechanism switches the opening / closing valve 63D to the closed position to close the outer nozzle 325. This prevents the warm air blown outward through the inner nozzle 355 from being further blown outward through the outer nozzle 325. As a result, the valve opening / closing mechanism can send the warm air blown outward through the inner nozzle 355 to the one heat storage space 52 or the other heat storage space 53.

[0081] Furthermore, the valve opening / closing mechanism switches the opening / closing valve 63D to the open position to open the outer nozzle 325 in the "spraying mode." This allows the valve opening / closing mechanism to allow the hot air blown outward through the inner nozzle 355 to be further blown outward through the outer nozzle 325. As a result, the hot air can be blown through the outer nozzle 325 onto the ink on the continuous substrate 9 being transported below the hot air blowing device 30.

[0082] In this way, in this modification, the on-off valve 63D and the valve on-off mechanism constitute a "switching device" that can switch between the "warm air mode" and the "spray mode." Furthermore, with this configuration, switching between the "warm air mode" and the "spray mode" can be performed reliably.

[0083] <3-3.Third modified example> Fig. 10 is a partially enlarged cross-sectional view of the vicinity of the outer nozzle 325 and inner nozzle 355 of a hot air blowing device 30E according to a third modified example. As shown in Fig. 10, the hot air blowing device 30E of this embodiment does not use the second blower fans 371, 372 provided in the hot air blowing device 30 of the first embodiment. However, the first blower fan 36 is provided and generates a flow of hot air from the inside to the outside of the inner wall portion 351 via the inner nozzle 355. In the hot air blowing device 30E of this embodiment, instead of the second blower fans 371, 372, a structure is provided in which at least a portion of the outer converging portion 324E of the outer wall portion 321E is displaceably supported. That is, the warm air blowing device 30E is provided with a displaceable displacement portion 328E that constitutes at least a part of the outer converging portion 324E of the outer wall portion 321E, a bearing 329E that displaceably supports the displacement portion 328E, and an outer wall opening / closing mechanism (not shown).

[0084] As shown in FIG. 10 , the displacement portion 328E is supported by a bearing 329E and is thus displaceable in the direction of arrow Dr in FIG. 10 . When in the closed position, the displacement portion 328E closes the outer nozzle 325. On the other hand, when in the open position, the displacement portion 328E opens the outer nozzle 325. Note that in FIG. 10 , the displacement portion 328E in the closed position is indicated by a solid line, and the displacement portion 328E in the open position is indicated by a dashed line. The outer wall opening / closing mechanism uses a driving force of a cylinder (not shown) or the like to displace the displacement portion 328E between a closed position where the outer nozzle 325 is closed and an open position where the outer nozzle 325 is opened. The outer wall opening / closing mechanism is electrically connected to a control unit 90. Based on data input from the temperature sensor 38, the control unit 90 drives the outer wall opening / closing mechanism to switch the displacement portion 328E between the open position and the closed position.

[0085] More specifically, in the "warm air mode," the outer wall opening / closing mechanism switches the displacement portion 328E to the closed position to close the outer nozzle 325. This causes the outer wall opening / closing mechanism to block the warm air blown outward through the inner nozzle 355 from being further blown outward through the outer nozzle 325. As a result, the outer wall opening / closing mechanism can send the warm air blown outward through the inner nozzle 355 to the one-side heat storage space 52 or the other-side heat storage space 53.

[0086] Furthermore, the outer wall opening / closing mechanism switches the displacement part 328E to the open position to open the outer nozzle 325 as the "spraying mode." This allows the outer wall opening / closing mechanism to allow the hot air blown outward through the inner nozzle 355 to be further blown outward through the outer nozzle 325. As a result, the hot air can be blown through the outer nozzle 325 onto the ink on the continuous substrate 9 being transported below the hot air blowing device 30.

[0087] In this manner, in this modification, the displacement portion 328E, the bearing 329E, and the outer wall opening / closing mechanism constitute a "switching device" that can switch between the "warm air mode" and the "blowing mode." With this configuration, the modification can open and close the outer nozzle 325 without providing an opening / closing mechanism near the outer nozzle 325, where space is limited. As a result, the "switching device" of this modification can be easily applied to the warm air blowing device 30E.

[0088] Furthermore, the elements appearing in the above-described embodiments and modifications may be combined as appropriate within the scope of not causing any contradiction. [Explanation of symbols]

[0089] 1. Inkjet printing device 9 Continuous substrate 10. Transport mechanism 20 Printing mechanism 21 Discharge head 30, 30B, 30C, 30D, 30E Hot air blowing device 31 Heat source 32 Outer housing 33 First partition 34 Second partition 35 Inner housing 36 First blower fan 38 Temperature Sensor 51 Central space 52 One-side heat storage space 53 Heat storage space on the other side 61B, 61C shutter plate 63D Opening and Closing Valve 90 Control Unit 321,321E Exterior wall 324,324E Outer convergence section 325 outer nozzle 328E Displacement section 329E bearing 330 (First partition plate) through hole 331 (First partition plate) through hole 340 (Second partition plate) through hole 351 Inner wall 355 Inner nozzle 371 Second blower fan 372 Second blower fan 611C (Shutter plate) fixing plate 612C (Shutter Plate) Slide Plate 613C (Fixed Plate) First Through Hole 614C (Slide plate) second through hole Dl (hot air blower) lateral direction Dw (for continuous substrate and hot air blower) width direction Fa (gas flow path from inside to outside of the inner nozzle) Fb1 (gas flow path toward one side heat storage space) Fb2 (gas flow path to the other heat storage space) Fc (gas flow path from inside to outside of the outer nozzle) PC closed position Po open position

Claims

1. A hot air blowing device that blows hot air onto ink on a print medium, a heat source that heats gas to generate the hot air; an inner housing having an inner wall surrounding the heat source; an inner nozzle formed in the inner wall portion at a position facing the print medium, for blowing the hot air from the inside to the outside of the inner wall portion; an outer housing having an outer wall portion provided outside the inner wall portion and surrounding the inner wall portion; an outer nozzle formed in the outer wall portion at a position facing the print medium and the inner nozzle, and configured to blow the hot air from the inside to the outside of the outer wall portion; a first blower fan that generates a flow of the hot air from the inside to the outside of the inner wall portion via the inner nozzle; a heat storage space formed between the inner wall portion and the outer wall portion; a switching device that can switch between a warm air mode in which the warm air blown outward through the inner nozzle is sent to the heat storage space by restricting the warm air from being blown outward through the outer nozzle, and a spray mode in which the warm air blown outward through the inner nozzle is sprayed onto the ink on the printing medium through the outer nozzle by allowing the warm air to be blown outward through the outer nozzle; A hot air blowing device having the above.

2. The hot air blowing device according to claim 1, The switching device a second blower fan that generates a flow of the hot air in the heat storage space in a direction away from the outer nozzle; a rotation control unit that controls rotation of the first blower fan and the second blower fan; and The rotation control unit is In the warm-up mode, the airflow rate of the first blower fan is set to be smaller than the airflow rate of the second blower fan, In the blowing mode, the hot air blowing device sets the air volume of the first blower fan to be larger than the air volume of the second blower fan.

3. The hot air blowing device according to claim 2, A warm air blowing device in which a circulation flow path is formed through which the warm air sent to the heat storage space is supplied again to the inside of the inner wall portion.

4. The hot air blowing device according to claim 1, The switching device a shutter plate that can open and close the outer nozzle from the outside of the outer wall portion; a shutter movement mechanism that reciprocates the shutter plate between an open position and a closed position; and The shutter movement mechanism includes: In the warm-up mode, the shutter plate is moved to the closed position, The hot air blowing device moves the shutter plate to the open position in the blowing mode.

5. The hot air blowing device according to claim 4, The shutter plate is When in the closed position, the outer nozzle is covered from the outside of the outer wall portion; a hot air blowing device that is spaced apart from the outer nozzle when in the open position;

6. The hot air blowing device according to claim 4, The shutter plate is a fixing plate fixed to the outer wall portion and covering the outer nozzle from the outside of the outer wall portion; a slide plate that overlaps the fixed plate and is supported slidably relative to the fixed plate; and the fixing plate has one or more first through holes penetrating the fixing plate, the slide plate has one or more second through holes penetrating the slide plate; The shutter plate is When in the closed position, the first through hole and the second through hole do not communicate with each other, When the hot air blowing device is in the open position, the first through hole and the second through hole communicate with each other.

7. The hot air blowing device according to claim 1, The switching device an opening / closing valve provided in the outer nozzle and capable of adjusting its opening degree; a valve opening / closing mechanism that switches the opening / closing valve between an open position and a closed position; and The valve opening and closing mechanism includes: In the warm-up mode, the on-off valve is switched to the closed position to close the outer nozzle; In the blowing mode, the opening / closing valve is switched to the open position to open the outer nozzle.

8. a transport mechanism that transports the print medium along a predetermined transport path; an ejection head that ejects droplets of the ink onto the surface of the print medium transported by the transport mechanism; a hot air blowing device according to claim 1 , which blows the hot air onto the ink on the print medium downstream of the ejection head along the transport path; An inkjet printing device comprising:

Images