JP2017043020A - Inkjet printing device - Google Patents

Abstract

An ink jet printing apparatus capable of reducing contact of paper with an ink jet head is provided. Ink jet heads 61A to 61D that discharge ink onto a long sheet of paper that is continuously transported and arranged below the ink jet heads 61A to 61D at intervals along the paper transport direction. Are provided below the plurality of head lower support rollers 26 to 30 and an airflow generation unit 9 that is disposed below the head lower support rollers 26 to 30 and generates an airflow along the paper transport direction. The airflow generation unit 9 has an airflow from the upstream side to the downstream side in the transport direction on the guide plate 91 arranged in parallel with the transport path of the paper P and the surface of the guide plate 91 on the head lower support rollers 26 to 31 side. And exhaust fans 97 for sucking the airflow from the upstream side in the transport direction on the surface of the guide plate 91 on the head lower support rollers 26 to 31 side. [Selection] Figure 1

Description

  The present invention relates to an inkjet printing apparatus that prints by ejecting ink from an inkjet head.

  2. Description of the Related Art An ink jet printing apparatus that prints by ejecting ink from an ink jet head while conveying a recording medium made of long continuous paper called a web is known. In this inkjet printing apparatus for web, when the distance from the nozzle surface of the inkjet head to the web increases, the landing position deviation due to the error in the ejection direction of the head itself or the shaking of the web being conveyed at high speed becomes significant. In addition, mist and satellites increase and image quality deteriorates. Therefore, in this web ink jet printing apparatus, the nozzle surface of the ink jet head is set at a distance of 1 mm or less with respect to the web in order to improve the image quality.

  By the way, in a web inkjet printing apparatus, for example, when a user notices a danger or abnormality in a printing apparatus and presses an emergency stop button, or when a power failure or an outlet is disconnected and power is not supplied to the printing apparatus, the printing apparatus May stop suddenly during execution of the printing process, for example, when it becomes physically unable to move due to a web jam or failure.

  In these cases, since the web wound in a roll shape on the uppermost stream and the lowermost stream of the web has a large inertia, even if the printing press stops suddenly, the conveyance of the web cannot be stopped suddenly. Since each roller in the printing section is not braked, each roller will continue to rotate due to inertia when it stops suddenly. In the direction opposite to the transport direction, slack may occur.

  As a countermeasure against the sudden stop of the web when such a printing apparatus is suddenly stopped, there is a technique disclosed in Patent Document 1. In the technology of this Patent Document 1, an emergency stop of the paper feeding device is performed by forming a so-called air loop by loosening the web by its own weight between the web take-in mechanism and the web transport mechanism, and controlling this air loop as a buffer. Absorbs the progress of the web due to inertial force. Thereby, at the time of the emergency stop of a paper feeder, the damage to a web conveyance mechanism etc. is avoided by ensuring time until the operation | movement of a web conveyance mechanism stops.

JP 2012-136301 A

  However, since the technique of Patent Document 1 is a method of absorbing the progress of the web due to the inertia force by controlling the buffer, there is a problem that it cannot cope with the slackness of the web that occurs in the vicinity of the inkjet head. When such web slack or breakage occurs, there is a risk of so-called head attack in which the web contacts the ink jet head. When the web contacts the nozzle, the print surface is soiled, the nozzle meniscus is destroyed, the nozzle surface is damaged, etc. May cause problems.

  The present invention has been made in view of the above, and an object of the present invention is to provide an ink jet printing apparatus that can reduce the contact of the paper with the ink jet head at the time of an abnormal stop or the like and avoid the occurrence of problems around the ink jet head.

  In order to achieve the above object, a first feature of an ink jet printing apparatus according to the present invention is that an ink jet head that ejects ink onto a continuous paper that is continuously transported, and a paper transport that is below the ink jet head. A plurality of support members arranged at intervals along the direction and supporting the paper; and an airflow generation means arranged below the support member and generating an airflow along the paper transport direction. is there.

  A second feature of the ink jet printing apparatus according to the present invention is that the airflow generating means is a guide plate that is a plate member arranged in parallel with the paper conveyance path, and the surface of the guide plate on the support member side. A blowing unit that generates an air flow from the upstream side toward the downstream side in the transport direction; and a suction unit that sucks an air stream from the upstream side in the transport direction on the surface of the guide plate on the support member side. There is.

  A third feature of the ink jet printing apparatus according to the present invention is that the ink jet printing apparatus further includes a duct portion that connects the intake port of the air blowing unit and the exhaust port of the suction unit so as to allow ventilation.

  According to the first feature of the ink jet printing apparatus according to the present invention, the air flow is generated by the air flow generating means so as to push down the paper between the support members by generating an air flow (rectification) along the paper transport direction. Can generate lift. Thereby, even when the paper is loosened or broken due to the abnormal stop of the paper conveyance, the approach of the paper to the inkjet head can be suppressed. As a result, the contact of the paper with the inkjet head can be reduced.

  According to the second feature of the ink jet printing apparatus of the present invention, lift can be more reliably generated on the paper by the guide plate disposed in parallel with the paper transport path. In particular, even when the conveyance path is curved, by matching the shape of the guide plate with the curvature of the conveyance path, it is possible to generate rectification that is parallel along the curve, Regardless of the characteristics of the transport path, the paper can be pushed down to prevent head attack.

  According to the third feature of the ink jet printing apparatus according to the present invention, it is generated by exhaust or intake by means for generating rectification by connecting the intake port in the blower means and the exhaust port in the suction means by a duct portion. It is possible to avoid the airflow around the conveyance path from being disturbed by the turbulent flow, and to further stabilize the guide plate-like rectification.

1 is a schematic configuration diagram of an inkjet printing apparatus according to an embodiment. It is a principal part top view of the conveyance part under a head of the inkjet printing apparatus shown in FIG. It is a control block diagram of the inkjet printing apparatus shown in FIG. It is a perspective view which shows the airflow generation | occurrence | production part shown in FIG. It is explanatory drawing which shows the operation | movement by which the paper is pushed down by the airflow generation part of the inkjet printing apparatus shown in FIG. It is a schematic diagram which shows the state which connected the air supply part and exhaust part which concern on the example of a change with the duct. It is explanatory drawing which shows the state which a paper contacts the inkjet head by a prior art example.

  Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, the same or equivalent parts and components are denoted by the same or equivalent reference numerals. The embodiments described below exemplify devices for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, The arrangement is not specified as follows. The technical idea of the present invention can be variously modified within the scope of the claims.

(Configuration of inkjet printer)
FIG. 1 is a schematic configuration diagram of an ink jet printing apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of the main part of the lower head transport section of the ink jet printing apparatus shown in FIG. FIG. 3 is a control block diagram of the inkjet printing apparatus shown in FIG. In the following description, the top, bottom, left, and right of the paper surface in FIG. Further, the direction orthogonal to the paper surface of FIG. FIG. 4 is a perspective view showing the airflow generation section shown in FIG.

  As shown in FIG. 1, the inkjet printing apparatus 1 according to the present embodiment includes a sending unit 2, an upstream buffer unit 20, an image forming unit 4, a downstream buffer unit 7, a winding unit 8, and an air flow. A generation unit 9 and a control unit 100 are provided.

  The sending unit 2 is a mechanism that sends out the paper P from the paper roll 10. The paper roll 10 is a roll of paper P, which is a long continuous paper. As shown in FIGS. 1 and 3, the delivery unit 2 includes a main motor 11.

  The main motor 11 is a driving unit that rotates a paper roll support shaft that rotatably supports the paper roll 10, and rotates the paper roll support shaft clockwise in FIG. The paper roll 10 rotates in the same direction by the rotation of the paper roll support shaft, and the paper P is sent out to the downstream side (right side). The paper roll support shaft is formed in a long shape extending in the front-rear direction in the figure, that is, in a direction orthogonal to the paper feeding direction.

  The upstream buffer unit 20 is a mechanism that absorbs the slack of the paper P between the sending unit 2 and the head lower conveyance unit 40. The upstream buffer unit 20 includes support rollers 16 and 17 and a dancer roller 18.

  The support rollers 16 and 17 support the paper P between the sending unit 2 and the head lower conveyance unit 40. The support rollers 16 and 17 are spaced apart from each other by a predetermined distance in the left-right direction and are disposed at the same height. The dancer roller 18 pushes down the paper P by its own weight between the support rollers 16 and 17. As a result, the slack of the paper P generated between the sending unit 2 and the head lower conveyance unit 40 is absorbed by the upstream buffer unit 20. The dancer roller 18 moves up and down according to the amount of slack of the paper P, and absorbs slack while maintaining the tension of the paper P.

  An outfeed motor 19 is provided on the downstream side of the upstream buffer unit 20. The outfeed motor 19 is a motor that feeds the paper P from the delivery unit 2 to the downstream side, and applies tension to the paper P. The outfeed motor 19 nips the paper P with the lower guide roller 19 a and is driven in synchronism with the main motor 11 of the paper roll 10 to absorb the slack in the upstream buffer unit 20 and the paper. A predetermined tension is applied to P.

  In the present embodiment, the second buffer unit 3 is provided on the downstream side of the upstream buffer unit 20. The second buffer unit 3 is a mechanism that absorbs the slack of the paper P sent out from the outfeed motor 19. The second buffer unit 3 includes support rollers 14 and 15 and a metal rod 13.

  The support rollers 14 and 15 are spaced apart from each other by a predetermined distance and arranged at the same height, and the paper P is supported between the support rollers 14 and 15 with a predetermined slack. In this way, the paper P is suspended in a U-shape downward by a predetermined length by its own weight between the support rollers 14 and 15. The metal bar 13 is a weight suspended along the paper P suspended in a U-shape between the support rollers 14 and 15, and has a U-shape so as to hold the suspended paper P. The movement trajectory of the formed paper P is regulated from the inside.

  The image forming unit 4 mainly includes a head lower transport unit 40, an airflow generation unit 9, and an inkjet head unit 6.

  The head lower transport unit 40 is a mechanism that transports the paper P sent out by the sending unit 2 along a transport path below the ink jet heads 61A to 61D described later. As shown in FIGS. 1 to 3, the head lower transport unit 40 includes upstream guide rollers 21 to 25, a powder brake 41, head lower support rollers 26 to 31, a head lower transport motor 32, and a downstream guide. A roller 33 and a pair of support plates 34F and 34R are provided. The under-head transport unit 40 includes laser Doppler sensors 44 and 45 and an encoder 43 for measuring the transport speed at key points in the path.

  The upstream guide rollers 21 to 25 are rollers that guide the paper P between the upstream buffer unit 20 and the head lower support roller 26. Among the upstream guide rollers, a powder brake 41 is disposed between the rollers 21 and 22. The powder brake 41 is a mechanism for braking the paper P, and suppresses the paper P from being fed to the ink jet head unit 6 side more than necessary. Of the upstream guide rollers, a tension sensor 42 is provided between the rollers 22 and 23 to measure the tension of the paper P on the upstream side of the inkjet head unit 6.

  The head lower support rollers 26 to 31 support the paper P below the ink jet heads 61A to 61D. A path connecting the highest points of the head lower support rollers 26 to 31 is a transport path of the paper P below the ink jet heads 61A to 61D. The head lower support rollers 26 to 31 are arranged in a parabolic shape so that the conveyance path has an upwardly convex shape with an interval along the paper conveyance direction (left-right direction). As for the head lower support rollers 26-31, each rotating shaft 26a-31a is supported by the support plates 34F and 34R.

  The head lower support roller 26 is disposed in the vicinity of the upstream side of the ink jet head 61A in the paper transport direction. The head lower support rollers 27, 28, and 29 are disposed between the inkjet heads 61A and 61B, between the inkjet heads 61B and 61C, and between the inkjet heads 61C and 61D, respectively, in the paper transport direction. In other words, the head lower support rollers 27, 28, and 29 are disposed in the vicinity of the downstream side of the inkjet heads 61A, 61B, and 61C and in the vicinity of the upstream side of the inkjet heads 61B, 61C, and 61D, respectively. The head lower support roller 30 is disposed in the vicinity of the downstream side of the ink jet head 61D in the paper transport direction. The head lower support roller 31 is disposed on the downstream side of the head lower support roller 30 in the paper transport direction.

  The under-head transport motor 32 rotates the drive roller 32c. The driving roller 32c conveys the paper P in the right direction by rotating while nipping the paper P with the upper roller 32b. The drive roller 32c is supported on the support plates 34F and 34R by the rotation shaft 32a.

  The support plates 34F and 34R rotatably support the rotation shafts 26a to 31a of the head lower support rollers 26 to 31 and the rotation shaft 32a of the drive roller 32c. The support plates 34F and 34R are spaced apart from each other in the front-rear direction across the transport path of the paper P. The downstream guide roller 33 guides the paper P between the head lower support roller 31 and the downstream buffer unit 7.

  The airflow generation unit 9 is a unit that is disposed below the head lower support rollers 26 to 30 and generates an airflow along the conveyance direction of the paper P. As illustrated in FIG. 93 and a suction part 95.

  The guide plate 91 is a plate member arranged in parallel with the transport path of the paper P. In the present embodiment, the guide plate 91 is disposed immediately below the lower head support rollers 26 to 30 of the inkjet head unit 6 and is curved in a convex shape toward the upper part so as to be parallel to the transport path of the paper P. It is formed in a state. The guide plate 91 is provided with a plurality of ribs 92 extending along the transport direction (sub-main scanning direction) on the surface (front surface) facing the head lower support rollers 26 to 30. Each of the ribs 92 is formed substantially in parallel, thereby generating an air flow (rectification) that is arranged along the conveyance direction of the paper P.

  The blower 93 is a blower that generates an airflow, and is arranged on the upstream side of the guide plate 91 in the transport direction. In the present embodiment, the air blower 93 includes a pair of suction fans 98 and 98 and a blower outlet 94.

  The suction fan 98 is a suction means for sucking ambient outside air into the duct, and in this embodiment, the suction fan 98 is disposed on both sides. The air outlet 94 is an opening that blows out the sucked air to the outside. In the present embodiment, the air outlet 94 is disposed on the front side of the guide plate 91 on the front side of the guide plate 91. Thereby, the air blower 93 generates an air flow from the upstream side to the downstream side in the transport direction on the surface of the guide plate 91 on the head lower support rollers 26 to 30 side. At this time, the air sent out from the blower section 93 flows along the guide plate 91 due to the Coanda effect, and is rectified by the rib 92 of the guide plate 91 and moves downstream. Although not shown in the drawing, a plurality of partition plates are formed in the duct of the air blowing section 93, and the air flow is adjusted to be uniform in the main scanning direction of the guide plate 91.

  The suction unit 95 is a suction unit that sucks the airflow, and is disposed on the downstream side of the guide plate 91 in the transport direction. In the present embodiment, the suction unit 95 includes a suction port 96 and a pair of exhaust fans 97 and 97.

  The exhaust fan 97 is a suction unit that is disposed on both sides of the duct and sucks air inside the duct and exhausts it outside. The exhaust fan 97 places the inside of the duct in a negative pressure state. The suction port 96 is a suction means that is provided at the terminal portion of the guide plate 91 and sucks air into the duct. In the present embodiment, the suction port 96 is disposed on the surface side of the guide plate 91 and sucks air into the duct in a negative pressure state. Thereby, the suction unit 95 sucks the airflow from the upstream side in the transport direction on the surface of the guide plate 91 on the head lower support rollers 26 to 30 side. In the present embodiment, the suction port 96 is provided with a filter 96a so as to adsorb mist drifting in the printing unit.

  The suction fan 98 and the exhaust fan 97 are controlled to be turned on / off by the control unit 100 and turned on when printing is started or when the power is turned on, and always generate an air flow from the upstream side to the downstream side in the transport direction during transport. It is like that. In particular, in the present embodiment, since the airflow is always generated, even in the abnormal stop that occurs when the power failure or the outlet is disconnected, the fan continues around for a while due to inertia, so the airflow does not disappear immediately, Even in the non-powered state, immediately after an abnormal stop, the lifting force that pushes down the paper P is maintained. The suction fan 98 and the exhaust fan 97 may be provided with an emergency power source for applied voltage in order to maintain more stable stability.

  The ink jet head unit 6 prints on the paper P conveyed on the head lower support rollers 26 to 31. The inkjet head unit 6 includes four inkjet heads 61A to 61D. In addition, the alphabetic suffixes (A to D) in the reference numerals of the ink jet heads 61A to 61D may be omitted and collectively described.

  The ink jet heads 61 </ b> A to 61 </ b> D discharge ink onto the conveyed paper P. The inkjet heads 61 </ b> A to 61 </ b> D are arranged in parallel along the conveyance direction (left-right direction) of the paper P. The inkjet heads 61A to 61D eject inks of different colors (for example, black, cyan, magenta, and yellow). Each of the inkjet heads 61 </ b> A to 61 </ b> D has six head modules 66.

  In the inkjet head 61, the head modules 66 are arranged in a staggered manner. That is, the ink jet head 61 is formed by arranging two head rows composed of three head modules 66 arranged at equal intervals in the front-rear direction so as to be shifted by a half pitch in the front-rear direction. . The head module 66 has a plurality of nozzles (not shown) arranged along the front-rear direction, and ejects ink from the nozzles.

  The downstream buffer unit 7 is a mechanism that absorbs slack of the paper P between the lower head transport unit 40 and the winding unit 8. The downstream buffer unit 7 includes support rollers 71 and 72 and a dancer roller 73.

  The support rollers 71 and 72 support the paper P between the head lower conveyance unit 40 and the winding unit 8. The support rollers 71 and 72 are arranged at the same height and spaced apart from each other by a predetermined distance in the left-right direction. The dancer roller 73 pushes down the paper P by its own weight between the support rollers 71 and 72. Thereby, the slack of the paper P generated between the head lower conveyance unit 40 and the winding unit 8 is absorbed by the downstream buffer unit 7. The dancer roller 73 moves up and down according to the amount of slack of the paper P.

  The winding unit 8 is a mechanism for winding the printed paper P. The winding unit 8 includes an infeed motor 86, an internal buffer unit 80, a downstream guide roller 84, and a winding motor 85.

  The winding motor 85 is a drive mechanism that rotates the winding shaft clockwise in FIG. The sheet P is wound around the winding shaft by the rotational drive of the winding motor 85. The take-up shaft is formed in a long shape extending in the front-rear direction, and is rotated by a take-up motor 85 to take up and hold the paper P.

  The infeed motor 86 is a drive motor that feeds the paper P sent from the downstream buffer unit 7 into the winding unit 8. An internal buffer unit is provided between the infeed motor 86 and the winding motor 85.

  The internal buffer unit 80 is a mechanism that absorbs slack of the paper P between the lower head transport unit 40 and the winding unit 8, and includes support rollers 81 and 82 and a dancer roller 83. The support rollers 81 and 82 support the paper P between the infeed motor 86 and the take-up motor 85. The support rollers 81 and 82 are arranged at the same height, spaced apart from each other by a predetermined distance in the left-right direction. The dancer roller 83 pushes down the paper P by its own weight between the support rollers 81 and 82. Thereby, the slack of the paper P generated between the in-feed motor 86 and the winding unit 8 is absorbed by the internal buffer unit 80. The dancer roller 83 moves up and down according to the amount of slack of the paper P.

  The control unit 100 controls the operation of each unit of the inkjet printing apparatus 1. The control unit 100 includes a CPU, RAM, ROM, hard disk, and the like.

(Operation of inkjet printer)
Next, the operation of the inkjet printing apparatus 1 will be described.
First, the control unit 100 starts a printing operation when a print job is input. Specifically, the control unit 100 activates the main motor 11, the outfeed motor 19, the powder brake 41, and the winding motor 85. As a result, the paper P is conveyed from the sending unit 2 toward the winding unit 8. In the lower head transport unit 40, the paper P is transported while tension is applied to the paper P by applying a brake to the paper P by the powder brake 41.

  At this time, the air flow generation unit 9 is also turned ON by the control unit 100, and an air flow is always generated along the transport direction of the paper P on the surface of the guide plate 91 on the head lower support rollers 26 to 30 side during transport. At this time, since the guide plate 91 is convexly curved toward the head lower support rollers 26 to 30, the flow velocity of the airflow flowing on the surface of the guide plate 91 is increased, and lift is generated. As a result, the paper P is always pushed downward between the head lower support rollers 26 and 27, between the head lower support rollers 27 and 28, between the head lower support rollers 28 and 29, and between the head lower support rollers 29 and 30. Sucked into. In addition, since a sufficient tension is applied to the sheet P during normal conveyance, the sheet P is not attracted to the guide plate 91 more than necessary due to this suction force, and the gap between the sheet P and the head nozzle surface. Is maintained at 1 mm or less.

  Thereafter, when the conveyance speed of the paper P reaches a predetermined speed, the control unit 100 starts printing by the inkjet head unit 6. Specifically, the control unit 100 controls the ink jet heads 61 </ b> A to 61 </ b> D based on the print job to eject ink onto the paper P to form an image.

  Then, after the start of the printing operation, for example, when an emergency situation such as detection of meandering of the paper P occurs, the control unit 100 performs an emergency stop of the paper transport operation. Specifically, the control unit 100 stops the main motor 11, the head lower conveyance motor 32, the powder brake 41, and the winding motor 85. Here, the control unit 100 prevents the main motor 11, the head lower conveyance motor 32, the powder brake 41, and the take-up motor 85 from stopping, the main motor 11, the head lower, so that the paper P does not loosen or break. The deceleration acceleration of the conveyance motor 32 and the winding motor 85 is controlled. When this paper transport operation is completed, a series of operations are completed.

  Here, since there is an emergency in the inkjet printing apparatus 1, the behavior of the paper P is disturbed when the paper transport operation is stopped, and thus the paper P may be loosened or broken. In this state, even if the ink jet printing apparatus suddenly stops and the paper P in the printing unit becomes slack, in this embodiment, as shown in FIG. 5, the paper P is generated by the lift generated by the airflow generation unit 9. Is pulled toward the guide plate 91 side, so that, when stopped, between the head lower support rollers 26 and 27, between the head lower support rollers 27 and 28, between the head lower support rollers 28 and 29, and between the head lower support rollers 29 and 30. Thus, the sheet P is sucked so as to be pushed down. In this embodiment, since the airflow is always generated, even in the abnormal stop that occurs when the power failure or the outlet is disconnected, the fan continues around for a while due to inertia, so the airflow does not disappear immediately, Even in the non-powered state, immediately after an abnormal stop, the lifting force that pushes down the paper P is maintained.

(Action / Effect)
As described above, in the ink jet printing apparatus 1, the air flow generation unit 9 generates an air flow (rectification) along the transport direction of the paper P, thereby lowering the paper P between the head lower support rollers 26 to 30. It is possible to generate lift such as pushing down.

  Thus, conventionally, when the paper P is loosened or broken due to the abnormal stop of the conveyance of the paper P, as shown in FIG. 7, a so-called head attack in which the paper P contacts the inkjet head has occurred. In the embodiment, even when the paper P is loosened or broken due to the abnormal stop of the conveyance of the paper P, the approach of the paper P to the ink jet heads 61A to 61D can be suppressed. As a result, the paper to the ink jet heads 61A to 61D can be suppressed. P contact can be reduced.

  Further, in the present embodiment, the airflow generation unit 9 generates an airflow along the transport direction of the paper P, which is the same direction as the airflow generated by the transport of the paper P, so that the airflow around the transport path is disturbed. And a stable mist suction effect can be obtained.

  Furthermore, according to the present embodiment, lift can be generated more reliably on the paper P by the guide plate 91 arranged in parallel with the transport path of the paper P. In particular, even when the conveyance path is curved, by making the shape of the guide plate 91 match the curvature of the conveyance path, it is possible to generate rectification parallel to the curvature. Regardless of the characteristics of the transport path, the paper P can be pushed down to prevent head attack.

(Example of change)
The present invention is not limited to the above-described embodiments as they are, but includes various embodiments that are not described herein, and can be embodied by modifying constituent elements without departing from the scope of the invention in the implementation stage. Various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiments. For example, some components may be deleted from all the components shown in the embodiment.

  For example, in the embodiment described above, the guide plate 91 is formed in a curved shape, but may be formed on the flat guide plate 91. In this case, the airflow generation unit 9 controls the front surface of the guide plate 91 to have a faster flow rate than the back surface, thereby generating lift.

  In the above-described embodiment, the air blowing unit 93 and the suction unit 95 are individually configured. However, the configuration of the airflow generation unit is not limited thereto. For example, as shown in FIG. 6, the suction fan 98 in the blower section 93 and the exhaust fan 97 in the suction section 95 may be connected by a duct section 99. In this case, by connecting the suction fan 98 in the blower section 93 and the exhaust fan 97 in the suction section 95 with the duct section 99, turbulent flow generated by exhaust or intake by means for generating rectification, It is possible to avoid disturbance of the airflow around the conveyance path and to stabilize the rectification of the guide plate 91.

P ... Paper 1 ... Inkjet printing apparatus 2 ... Sending unit 3 ... Second buffer unit 4 ... Image forming unit 6 ... Inkjet head unit 7 ... Downstream buffer unit 8 ... Winding unit 9 ... Airflow generating unit 10 ... Paper roll 11 ... Main motor 13 ... Metal rod 14, 15 ... Support roller 16, 17 ... Support roller 18 ... Dancer roller 19 ... Outfeed motor 19a ... Guide roller 20 ... Upstream buffer section 21-25 ... Upstream guide roller 26a-31a, 32a Rotating shaft 26-31 ... Head lower support roller 32 ... Head lower transport motor 32b ... Upper roller 32c ... Drive roller 33 ... Downstream guide rollers 34F, 34R ... Support plate 40 ... Head lower transport section 41 ... Powder brake 42 ... Tension Sensor 61 ... Inkjet head 61A ~ 1D ... Inkjet head 66 ... Head module 71, 72 ... Support roller 73 ... Dancer roller 80 ... Internal buffer part 81, 82 ... Support roller 83 ... Dancer roller 84 ... Downstream guide roller 85 ... Winding motor 86 ... Infeed motor 91 ... Guide plate 92 ... Rib 93 ... Air blower 94 ... Air outlet 95 ... Suction part 96 ... Suction port 96a ... Filter 97, 97 ... Exhaust fan 98, 98 ... Suction fan 99 ... Duct part 100 ... Control part

Claims (3)

An inkjet head that ejects ink onto a continuously long sheet of paper,
Below the inkjet head, a plurality of support members arranged at intervals along the paper transport direction and supporting the paper,
An ink jet printing apparatus, comprising: an airflow generating unit that is disposed below the support member and generates an airflow along a conveyance direction of the paper. The airflow generating means is
A guide plate which is a plate member arranged in parallel with the paper conveyance path;
On the surface of the guide plate on the support member side, air blowing means for generating an air flow from the upstream side to the downstream side in the transport direction;
The inkjet printing apparatus according to claim 1, further comprising: a suction unit configured to suck an airflow from an upstream side in the transport direction on a surface of the guide plate on the support member side.   The inkjet printing apparatus according to claim 2, further comprising a duct portion that connects the intake port of the blower unit and the exhaust port of the suction unit so as to allow ventilation.