JP6237591B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus.

  An ink jet recording apparatus is known as a kind of recording apparatus. Inkjet recording apparatuses are widely used in printers, copiers, multifunction machines, and the like. An ink jet recording apparatus records an image on a recording medium such as paper by ejecting ink droplets from nozzles of a recording head.

  The ink jet recording apparatus cannot eject ink droplets when a foreign substance such as paper dust adheres to the nozzle. As a result, an image defect occurs. For this reason, various techniques for suppressing the adhesion of foreign matter to the nozzle have been proposed.

  For example, an ink jet recording apparatus described in Patent Document 1 includes a casing provided on the upstream side of the recording head in the conveyance direction of the recording medium, and an air supply unit provided in the casing. With such a configuration, air is supplied from the air supply unit to the recording medium conveyed into the housing, and foreign matter is removed from the recording medium. As a result, the recording medium from which the foreign matter has been removed is conveyed below the recording head. Therefore, the adhesion of foreign matter to the nozzle is suppressed.

JP 2011-183746 A

  However, the ink jet recording apparatus described in Patent Document 1 includes a dedicated air supply unit and a space where the air supply unit is disposed (internal space of the housing) in order to remove foreign matters such as paper dust. Need. For this reason, there exists a problem of causing the enlargement of an apparatus. There is also a problem that the configuration becomes complicated.

  The present invention has been made in view of the above problems, and an object thereof is to provide an ink jet recording apparatus that can suppress adhesion of foreign matters to nozzles with a simple configuration.

  The ink jet recording apparatus of the present invention records an image on a recording medium by ejecting ink droplets. The ink jet recording apparatus includes a guide member, a transport unit, a suction unit, a space forming member, and a recording head. The guide member guides the recording medium from the first area to the second area. The guide member has a plurality of grooves. The plurality of grooves extend in a first direction in which the recording medium is conveyed. The guide member has a through hole that opens into the groove and communicates with the groove, and a support surface. The plurality of grooves are formed in the support surface along the first direction and a second direction orthogonal to the first direction. The transport unit transports the recording medium from the first area to the second area along the support surface. The suction part generates a suction force in the groove through the through hole. The space forming member faces the support surface in the first region, and forms a foreign substance recovery space between the space forming member and the support surface. The recording head is opposed to the support surface in the second area, and discharges the ink droplets onto the recording medium conveyed to the second area. Further, in the ink jet recording apparatus, the plurality of grooves include a plurality of first grooves. The plurality of first grooves extend from the first region to a position upstream of the second region with respect to the first direction. The through hole in the first groove is provided at a position closer to the first region than the second region, or in the first region.

  According to the present invention, adhesion of foreign matter to the nozzle can be suppressed with a simple configuration.

1 is a diagram illustrating a configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is a top view which shows the conveyance belt which concerns on embodiment of this invention. It is a top view which shows the conveyance board which concerns on embodiment of this invention. (A) It is a top view which shows the groove | channel and through-hole of a conveyance board which concern on embodiment of this invention. (B) It is sectional drawing of the groove | channel and through-hole along the AA line shown to Fig.4 (a). It is a figure which expands and shows a part of recording part which concerns on embodiment of this invention. It is a figure which shows the structure of the recording part which concerns on embodiment of this invention. It is a figure which shows the structure of the vicinity of the plate-shaped member which concerns on embodiment of this invention. It is a figure which shows the positional relationship of the plate-shaped member which concerns on 1st Embodiment of this invention, and the groove | channel and through-hole of a conveyance board. It is a figure which shows the comparative example of the positional relationship of a plate-shaped member and the groove | channel and through-hole of a conveyance board. It is a figure which shows a mode when a paper approachs into the narrow space which concerns on embodiment of this invention. It is a figure which shows a mode when a paper leaves | separates from the narrow space which concerns on embodiment of this invention. It is a figure which shows the other example 1 of the positional relationship between the plate-shaped member which concerns on 1st Embodiment of this invention, and the groove | channel and through-hole of a conveyance board. It is a figure which shows the other example 2 of the positional relationship of the plate-shaped member which concerns on 1st Embodiment of this invention, and the groove | channel and through-hole of a conveyance board. It is a figure which shows the groove | channel and through-hole below the plate-shaped member which concern on 2nd Embodiment of this invention. It is a figure which shows a mode that a paper contacts a plate-shaped member. It is a figure which shows the other mode that a paper contacts a plate-shaped member. It is a figure which shows another mode that a paper contacts a plate-shaped member. It is a figure which shows the effect of the downward groove | channel and through-hole of the plate-shaped member which concerns on 2nd Embodiment of this invention. It is a figure which shows the other example 1 of the groove | channel and through-hole below the plate-shaped member which concerns on 2nd Embodiment of this invention. It is a figure which shows the other example 2 of the downward groove | channel and through-hole of a plate-shaped member which concerns on 2nd Embodiment of this invention. It is a figure which shows the other example 3 of the downward groove | channel and through-hole of a plate-shaped member which concerns on 2nd Embodiment of this invention. It is a figure which shows the modification of the groove | channel and the through-hole below the plate-shaped member which concerns on 2nd Embodiment of this invention. It is a figure which shows the other example 1 of a structure of the recording part which concerns on embodiment of this invention. It is a figure which shows the position of the partition plate which concerns on embodiment of this invention. It is a figure which shows the other example 2 of a structure of the recording part which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, in the figures, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated. In order to facilitate understanding, the drawings schematically show each component as a main component. The materials, shapes, dimensions, etc. shown in the following embodiments are merely examples, and are not particularly limited.

(First embodiment)
FIG. 1 is a diagram illustrating a configuration of an ink jet recording apparatus according to the present embodiment. The ink jet recording apparatus 1 ejects ink droplets and records an image on paper P (an example of a recording medium). The inkjet recording apparatus 1 includes an apparatus housing 100, a paper feeding unit 2 disposed below the inside of the device housing 100, a recording unit 3 disposed above the paper feeding unit 2, and one of the recording units 3. A sheet conveying unit 4 disposed on the side (right side in FIG. 1) and a sheet discharging unit 5 disposed on the other side (left side in FIG. 1) of the recording unit 3 are provided.

  The paper feed unit 2 feeds the paper P to the paper transport unit 4. The paper feed unit 2 includes a paper feed cassette 21 detachably attached to the apparatus housing 100, a paper feed roller 22, and a guide plate 23. The paper feed roller 22 is disposed above one end side (right end in FIG. 1) of the paper feed cassette 21. The guide plate 23 is disposed between the paper feed roller 22 and the paper transport unit 4.

  The paper feed cassette 21 can store a plurality of sheets of paper P. The paper feed roller 22 (pickup roller) takes out the paper P one by one from the paper feed cassette 21 and feeds it toward the guide plate 23. The guide plate 23 guides the paper P taken out by the paper feed roller 22 to the paper transport unit 4.

  The paper transport unit 4 transports the paper P to the recording unit 3. The paper transport unit 4 includes a substantially C-shaped paper transport path 41, a first transport roller pair 42 provided on the entrance side of the paper transport path 41, and a second transport roller pair provided in the middle of the paper transport path 41. 43 and a registration roller pair 44 provided on the exit side of the sheet conveyance path 41.

  The paper transport path 41 is constituted by a guide plate. The first transport roller pair 42 sends out the paper P fed from the paper feed unit 2 into the paper transport path 41. The second transport roller pair 43 feeds the paper P sent by the first transport roller pair 42 toward the registration roller pair 44 with the paper P sandwiched therebetween.

  The registration roller pair 44 performs skew correction of the paper P sent out by the second transport roller pair 43. In addition, the registration roller pair 44 temporarily stops the paper P and synchronizes the recording timing of the image onto the paper P with the conveyance timing of the paper P to the recording unit 3. The data is sent to the recording unit 3 at the recording timing. More specifically, the sheet P comes into contact with the registration roller pair 44 and stops. The skew correction of the paper P is performed by this contact. Thereafter, the registration roller pair 44 sends the paper P to the recording unit 3 in accordance with the image recording timing.

  The recording unit 3 records an image on the paper P while conveying the paper P. The recording unit 3 includes a conveyance unit 31, a conveyance plate 32 (an example of a guide member), a conveyance guide 33, four types of recording heads 34a, 34b, 34c, and 34d, and a plate-like member 35 (an example of a space forming member). ), A head base 36, and a suction part 37. Since the four types of recording heads 34a, 34b, 34c, and 34d have substantially the same configuration, they may be collectively referred to as the recording head 34.

  The transport unit 31 transports the paper P sent from the registration roller pair 44. The conveyance unit 31 includes a conveyance belt 310 (an example of an endless belt). The conveyance unit 31 rotates the conveyance belt 310 in a predetermined rotation direction (counterclockwise direction in FIG. 1). The paper P sent out by the registration roller pair 44 is guided onto the transport belt 310. As the conveyance belt 310 rotates, the paper P is conveyed.

  The conveyance plate 32 supports the conveyance belt 310 and supports the paper P via the conveyance belt 310. The conveyance plate 32 guides the paper P conveyed by the conveyance unit 31 (conveyance belt 310) in the direction indicated by the arrow X (sub-scanning direction). Hereinafter, the direction in which the paper P is transported by the transport unit 31 (the transport belt 310) is referred to as a paper transport direction X.

  The conveyance guide 33 is arranged on the downstream side (left side in FIG. 1) of the conveyance plate 32 with respect to the sheet conveyance direction X. Therefore, the conveyance plate 32 guides the paper P to the conveyance guide 33. That is, the transport unit 31 sends the paper P to the transport guide 33. The transport guide 33 guides the paper P sent out by the transport unit 31 to the paper discharge unit 5.

  The recording head 34 is held by the head base 36 and disposed above the conveyance unit 31, and faces the conveyance plate 32 via the conveyance belt 310. The recording head 34 records an image on the paper P while the transport unit 31 (transport belt 310) transports the paper P. Specifically, the recording head 34 ejects ink droplets toward the paper P that passes through a position facing the recording head 34. As a result, images such as characters and figures are recorded on the paper P.

  The plate-like member 35 is fixed to the surface of the head base 36 on the conveying unit 31 side (conveying plate 32 side) and is disposed above the conveying unit 31. That is, the plate-like member 35 faces the conveyance plate 32 with the conveyance belt 310 interposed therebetween. By fixing the plate member 35 to the head base 36, the plate member 35 can be easily arranged at a predetermined position.

  The plate-like member 35 is arranged on the upstream side (right side in FIG. 1) of the recording head 34 with respect to the paper transport direction X. Specifically, the plate-like member 35 is disposed on the upstream side of the recording head 34a located on the most upstream side in the paper transport direction X among the recording heads 34a, 34b, 34c, and 34d. Accordingly, the paper P passes below the plate-like member 35, then passes below the recording head 34, and reaches the conveyance guide 33. Hereinafter, the recording head 34a may be referred to as the most upstream recording head 34a.

  The suction unit 37 is disposed below the conveyance plate 32. The suction unit 37 sucks the paper P toward the transport belt 310 via the transport plate 32 and the transport belt 310. As a result, the paper P is attracted to the transport belt 310.

  The paper discharge unit 5 discharges the paper P to the outside of the apparatus housing 100. The paper discharge unit 5 includes a discharge roller pair 51 and a discharge tray 52. The discharge tray 52 is fixed to the apparatus casing 100 so as to protrude outward from the discharge port 11 formed in the apparatus casing 100. The discharge port 11 is formed on one side surface (left side surface in FIG. 1) of the apparatus housing 100.

  The discharge roller pair 51 sends the paper P that has passed through the conveyance guide 33 in the direction of the discharge port 11. The paper P delivered by the discharge roller pair 51 is guided by the discharge tray 52, discharged to the outside of the apparatus housing 100 through the discharge port 11, and placed on the discharge tray 52. When images are continuously recorded on a plurality of sheets P, the plurality of sheets P are stacked on the discharge tray 52.

  FIG. 2 is a plan view showing the conveyor belt 310. As shown in FIG. 2, a plurality of suction holes 311 are formed in the transport belt 310. The diameter of the suction hole 311 may be 2 mm. Further, the interval between adjacent suction holes 311 may be 8 mm.

  The plurality of suction holes 311 are arranged along the paper transport direction X and the direction (main scanning direction) orthogonal to the paper transport direction X. Hereinafter, a direction (second direction) orthogonal to the sheet conveyance direction X (first direction) is referred to as a sheet width direction. The plurality of suction holes 311 can be arranged in a staggered manner as shown in FIG.

  FIG. 3 is a plan view showing the transport plate 32. Specifically, FIG. 3 shows a part of the surface 320 of the transport plate 32 on the recording head 34 (see FIG. 1) side. Hereinafter, the surface 320 on the recording head 34 side of the transport plate 32 may be referred to as a support surface 320. The transport plate 32 supports the paper P by the support surface 320 via the transport belt 310 (see FIG. 1).

  The conveyance plate 32 is made of a metal material. Specifically, as the material of the conveying plate 32, an aluminum die cast, a pressed plate, or the like can be used. Alternatively, it is possible to select a resin excellent in slidability with the conveyor belt 310 as the material of the conveyor plate 32. When the transport plate 32 is made of a metal material, the transport plate 32 can be grounded.

  As shown in FIG. 3, a plurality of grooves 321 are formed on the support surface 320. Each groove 321 is a long groove opened on the recording head 34 (see FIG. 1) side. Specifically, each groove 321 has an oval shape extending in the paper transport direction X.

  The plurality of grooves 321 are arranged along the paper transport direction X and the paper width direction. The plurality of grooves 321 may be arranged in a staggered manner as shown in FIG. Specifically, the plurality of grooves 321 are arranged at positions that can face the suction holes 311 (see FIG. 2) of the transport belt 310. That is, the plurality of grooves 321 are arranged at a position where they can communicate with the suction hole 311. With this arrangement, the suction holes 311 facing the grooves 321 are replaced one by one as the conveyance belt 310 advances (rotates). Each groove 321 is formed so as to face at least two suction holes 311.

  A plurality of through holes 322 are formed in the transport plate 32. The plurality of through holes 322 are located in the plurality of grooves 321. Specifically, at least one through hole 322 is located in each groove 321. Each through hole 322 communicates with a corresponding groove 321. The cross section of each through hole 322 may be circular. As shown in FIG. 3, the plurality of through holes 322 can be arranged in a staggered manner.

  4A is a plan view showing the groove 321 and the through hole 322 of the transport plate 32, and FIG. 4B is the groove 321 and the through hole along the line AA shown in FIG. 4A. FIG. As shown in FIGS. 4A and 4B, the through hole 322 passes through the transport plate 32 in the thickness direction (vertical direction in FIG. 4B), and one end of the through hole 322. Open into the corresponding groove 321.

  Next, an area (position) through which the paper P conveyed by the conveyance unit 31 (conveyance belt 310) passes will be described with reference to FIG. FIG. 5 is an enlarged view of a part of the recording unit 3. Specifically, FIG. 5 shows a configuration around the head base 36. FIG. 5 shows a cross section of the transport plate 32 for easy understanding.

  As shown in FIG. 5, the paper P is transported from the first region A to the second region B along the support surface 320 (see FIG. 3) of the transport plate 32. In other words, the transport plate 32 guides the paper P from the first area A to the second area B. The first region A is a region below the plate-like member 35, and the plate-like member 35 faces the conveyance plate 32 (support surface 320) via the conveyance belt 310 in the first region A. The second area B is an area below the recording head 34, and the recording head 34 faces the conveyance plate 32 (support surface 320) via the conveyance belt 310 in the second area B.

  Next, the configuration of the recording unit 3 will be described with reference to FIGS. 1, 2, 5, and 6. FIG. 6 is a diagram illustrating a configuration of the recording unit 3. FIG. 6 shows a cross section of the transport plate 32 and a cross section of a part of the suction portion 37 (box-like member 371) for easy understanding.

  The transport unit 31 faces the recording head 34 in the apparatus housing 100 (see FIG. 1). The conveyance unit 31 includes a drive roller 312, a belt speed detection roller 313, a tension roller 314, and a pair of guide rollers 315 arranged on the inner peripheral side of the conveyance belt 310. The transport unit 31 further includes a suction roller 316 disposed on the outer peripheral side of the transport belt 310.

  The conveyance belt 310 is stretched around a driving roller 312, a belt speed detection roller 313, a tension roller 314, and a pair of guide rollers 315. A transport plate 32 and a suction unit 37 are disposed on the inner peripheral side of the stretched transport belt 310. The conveyance plate 32 faces the recording head 34 and the plate-like member 35 with the conveyance belt 310 interposed therebetween. The suction unit 37 is disposed below the transport plate 32 on the inner peripheral side of the transport belt 310.

  The driving roller 312 is disposed on the downstream side (left side in FIG. 6) of the transport plate 32 with respect to the paper transport direction X. The driving roller 312 is rotationally driven by a motor (not shown), and rotates the conveyance belt 310 in a predetermined rotation direction (counterclockwise direction in FIG. 6). As the transport belt 310 rotates, the paper P is transported in the paper transport direction X.

  The belt speed detection roller 313 is arranged on the upstream side (the right side in FIG. 6) with respect to the paper transport direction X from the transport plate 32, and rotates due to friction generated between the belt speed detection roller 313 and the transport belt 310. Preferably, the belt speed detection roller 313 is arranged so as to maintain the flatness of the conveyance belt 310 at a location facing the recording head 34 together with the driving roller 312.

  The belt speed detection roller 313 includes a pulse plate (not shown), and the pulse plate rotates integrally with the belt speed detection roller 313. By measuring the rotational speed of the pulse plate, the rotational speed of the conveyor belt 310 is detected.

  The tension roller 314 applies tension to the conveyance belt 310 so that the conveyance belt 310 does not bend. The pair of guide rollers 315 guides the conveyor belt 310 so that the conveyor belt 310 passes below the suction unit 37.

  The suction roller 316 is a driven roller. The suction roller 316 faces the upstream end of the transport plate 32 in the paper transport direction X via the transport belt 310. The suction roller 316 guides the paper P sent from the registration roller pair 44 (see FIG. 1) onto the transport belt 310 and causes the transport belt 310 to suck the paper P.

  The suction unit 37 sucks air through the grooves 321 and the through holes 322 of the transport plate 32 and the suction holes 311 (see FIG. 2) of the transport belt 310. By this suction, wind is generated in the space below the head base 36. When the paper P is guided onto the transport belt 310 and covers a part of the transport belt 310, a suction force (negative pressure) acts on the paper P and the paper P is attracted to the transport belt 310. The suction part 37 includes a box-shaped member 371 whose upper surface is open, a first suction device 372a, a second suction device 372b, a first duct 373a, and a second duct 373b.

  The conveyance plate 32 is disposed so as to cover the upper surface opening of the box-shaped member 371. A pressure chamber 374 is defined by the transport plate 32 and the box-shaped member 371. The pressure chamber 374 communicates with the suction hole 311 of the transport belt 310 through the through hole 322 and the groove 321 of the transport plate 32.

  The first suction device 372a and the second suction device 372b are fixed to the lower surface of the box-shaped member 371. Specifically, a first opening 375a and a second opening 375b are formed on the bottom wall of the box-shaped member 371, and the first suction device 372a is disposed corresponding to the first opening 375a, and the second suction device 372b is disposed corresponding to the second opening 375b.

  The first opening 375 a is formed below the plate-like member 35, and the second opening 375 b is formed below the recording head 34. That is, the first suction device 372a is located below the plate-like member 35 (below the first region A shown in FIG. 5), and the second suction device 372b is below the recording head 34 (second state shown in FIG. 5). It is located under (region B). Accordingly, the first suction device 372a generates a negative pressure (suction force) below the first region A, and the second suction device 372b generates a negative pressure (suction force) below the second region B.

  The first duct 373a is connected to the lower surface of the first suction device 372a. The second duct 373b is connected to the lower surface of the second suction device 372b.

  By driving the first suction device 372a and the second suction device 372b, a negative pressure (gauge pressure) of 500 Pa is generated in the pressure chamber 374. Due to this negative pressure, a suction force is generated in the groove 321 through the through hole 322, and a suction force is generated in the suction hole 311 of the transport belt 310 through the groove 321. As a result, air is sucked into the pressure chamber 374 through the suction hole 311 of the transport belt 310, the groove 321 of the transport plate 32, and the through hole 322 of the transport plate 32. The air sucked into the pressure chamber 374 is exhausted through the first suction device 372a, the second suction device 372b, the first duct 373a, and the second duct 373b. Further, when the paper P is guided onto the conveyance belt 310 and blocks some of the plurality of suction holes 311, a suction force (negative pressure) acts on the paper P from the suction holes 311 closed by the paper P. Then, the paper P is adsorbed to the transport belt 310.

  The first suction device 372a and the second suction device 372b are fans. However, the first suction device 372a and the second suction device 372b are not limited to fans, and may be vacuum pumps, for example.

  In the present embodiment, the suction force of the first suction device 372a is larger than the suction force of the second suction device 372b. For this reason, the suction force of the groove 321 formed below the plate-like member 35 (first area A) is greater than the suction force of the groove 321 formed below the recording head 34 (second area B). large. Accordingly, the suction force of the suction hole 311 passing through the first region A is larger than the suction force of the suction hole 311 passing through the second region B. As a result, the speed (wind speed) of the air flow flowing into the suction hole 311 in the first region A is larger than the speed (wind speed) of the air flow flowing into the suction hole 311 in the second region B. That is, the wind speed of the wind generated below the plate-like member 35 is larger than the wind speed of the wind generated below the recording head 34.

  Each of the four types of recording heads 34a, 34b, 34c, and 34d can eject ink droplets of different colors. Specifically, black, cyan, magenta, and yellow ink droplets can be ejected from the recording heads 34a, 34b, 34c, and 34d, respectively.

  Further, the recording head 34 is held by the head base 36 and can be supported at such a height that a predetermined interval (1 mm) is formed between the recording head 34 and the conveying belt 310. The ink jet recording apparatus 1 may include a mechanism for moving the head base 36 up and down according to the thickness of the paper P (recording medium) conveyed by the conveying belt 310. With such a configuration, it is possible to support the recording head 34 at such a height that a predetermined distance (1 mm) is formed between the recording head 34 and the paper P.

  The four types of recording heads 34a, 34b, 34c, and 34d are arranged in parallel from the upstream side to the downstream side in the paper transport direction X (leftward in FIG. 6). The recording head 34 includes a plurality of nozzles (not shown) arranged in the paper width direction (in FIG. 6, the direction orthogonal to the paper surface). Ink droplets are ejected from a plurality of nozzles, and images such as characters and figures are recorded on the paper P.

  The recording head 34 is called a line head. That is, the ink jet recording apparatus 1 is a line head type ink jet recording apparatus. In the present embodiment, the length of the recording head 34 in the paper width direction is equal to or greater than the maximum width of the recording medium that can be guided by the transport plate 32 (that is, the ink jet recording apparatus 1 can record).

  The plate-like member 35 is fixed to the head base 36 and is disposed between the most upstream recording head 34 a and the suction roller 316. The length of the plate-like member 35 in the paper transport direction X is 60 mm. At least the lower surface of the plate-like member 35 can be made of a conductor. Stainless steel or the like can be used as the conductor. The whole plate-like member 35 or the conductor that partially constitutes the plate-like member 35 can be grounded. The plate-like member 35 forms a narrow gap space 351 (an example of a foreign matter recovery space) between the conveyance belt 310 and the plate-like member 35. The narrow space 351 is formed in the first region A.

  The plate-like member 35 forms a narrow space 351 upstream of the most upstream recording head 34 a in the paper transport direction X, and generates wind in the narrow space 351. Due to the wind, foreign matters such as paper dust can be peeled off from the paper P. That is, there is a possibility that foreign matter is attached to the paper P sent from the registration roller pair 44 to the recording unit 3. On the other hand, by providing the plate-like member 35, the foreign matter can be separated from the paper P in the first area A before the paper P enters the second area B. By separating the foreign matter from the paper P in the first area A, the amount of foreign matter conveyed to the lower side (second area B) of the recording head 34 can be reduced. As a result, the adhesion of foreign matter to the nozzles of the recording head 34 can be suppressed.

  Foreign matter can occur during the papermaking process. Specifically, cutting powder (paper dust) may be generated on the cut surface of the paper P in the cutting process, and may adhere to the paper P. Further, the surfaces of the paper P may rub against each other during packing, and foreign matters such as paper powder, calcium carbonate, and talc may be peeled off from the paper P and adhere to the paper P.

  Further, paper dust may be generated when the paper P is conveyed in the inkjet recording apparatus 1. For example, when the paper P is rubbed against the paper feed roller 22, fibers and fillers may be peeled off from the paper P, and may become paper dust and adhere to the paper P. Similarly, the paper P may be rubbed with a transport roller such as the first transport roller pair 42 to generate paper dust. Further, there is a possibility that the paper P is rubbed against the guide plate constituting the paper transport unit 4 to generate paper dust. Further, when the paper feed roller 22 picks up the paper P, the paper P to be picked up may rub against the paper P stored in the paper feed cassette 21 to generate paper dust.

  Further, there is a possibility that foreign matters such as paper dust adhering to the paper P may adhere to the transport rollers such as the first transport roller pair 42. In this case, the foreign matter adhering to the transport roller may adhere again to the paper P to be transported later, and as a result, the amount of foreign matter transported by the paper P at a time may increase.

  Various air flows are generated inside the apparatus housing 100 of the inkjet recording apparatus 1. For example, air flows from above the conveyor belt 310 to the pressure chamber 374. Further, as the paper P is transported, an air flow in the paper transport direction X occurs. Accordingly, the sheet P passes under the recording head 34 while being hit by the wind. Further, since the space between the recording head 34 and the conveyance belt 310 is narrow, a relatively strong wind is likely to be generated between the recording head 34 and the conveyance belt 310. Accordingly, the environment below the recording head 34 is an environment in which foreign matter is likely to be blown off from the paper P by the wind. Therefore, there is a possibility that the foreign matter blown off from the paper P adheres to the nozzles of the recording head 34.

  The adhesion of paper dust is generally dominated by the Coulomb force. For this reason, when an electric field is generated between the transport plate 32 and the recording head 34, the paper powder may fly and be attracted to the recording head 34 by the electric force. As a result, paper dust may adhere to the nozzles of the recording head 34.

  In the present embodiment, foreign matter such as paper dust is peeled off the paper P by generating wind in the narrow space 351. The air flowing in the narrow space 351 needs to flow at a sufficient wind speed to separate the foreign matter from the paper P. In the present embodiment, by adjusting the thickness of the plate-like member 35, the cross-sectional area of the air inlet of the narrow space 351 is set small. As a result, a wind having a sufficient wind speed is generated in the narrow space 351 to separate the foreign matter from the paper P. Specifically, when the sheet P enters the narrow space 351, a wind (air flow) with a wind speed of 6.0 m / second or more is generated at the air inlet of the narrow space 351, thereby the sheet P. The foreign matter can be peeled off. The separated foreign matter is sucked into the pressure chamber 374 and is discharged from the first duct 373a mainly through the first suction device 372a.

  A first hole 361 is formed in the head base 36. The first hole 361 is located upstream of the plate-shaped member 35 with respect to the paper transport direction X (on the right side in FIG. 6). A second hole 362 is formed in the head base 36. The second hole 362 is located downstream of the plate-like member 35 with respect to the paper transport direction X (left side in FIG. 6). In other words, the first hole 361 and the second hole 362 are provided so as to sandwich the plate-like member 35 in the paper transport direction X.

  Each of the first hole 361 and the second hole 362 is a long hole extending in the paper width direction. When the pressure chamber 374 becomes negative pressure, air flows into the narrow space 351 through the first hole 361 and the second hole 362. In this embodiment, the case where the first hole 361 and the second hole 362 extending in the paper width direction are formed in the head base 36 will be described, but the present invention is not limited to this. The hole formed in the head base 36 may have a shape other than the long hole. For example, a plurality of substantially cylindrical holes may be formed along the paper width direction.

  Next, the distance TD between the plate-like member 35 and the paper P (recording medium) will be described with reference to FIG. FIG. 7 is a diagram showing a configuration in the vicinity of the plate member 35.

  In the present embodiment, the distance TD between the plate-like member 35 and the paper P is 1.5 mm or more and 3.0 mm or less. The distance TD is 2 mm, for example. By setting the distance TD in this way and generating a negative pressure (gauge pressure) of 500 Pa in the pressure chamber 374, the air inlet (specifically, the plate-like member 35, the paper P, In the meantime, a wind having a wind speed of 6.0 m / sec or more can be generated.

  Next, the positional relationship between the plate-like member 35 and the grooves 321 and the through holes 322 of the transport plate 32 will be described with reference to FIG. FIG. 8 is a diagram illustrating a positional relationship between the plate-like member 35 and the grooves 321 and the through holes 322 of the transport plate 32.

  As shown in FIG. 8, the plurality of grooves 321 include a plurality of first grooves 321a extending from below the plate member 35 to the outside of the plate member 35 toward the most upstream recording head 34a. That is, each first groove 321 a extends (projects) from the lower side of the plate-like member 35 to the downstream side of the plate-like member 35 in the paper transport direction X.

  The downstream end of each first groove 321a in the paper transport direction X is located between the plate-like member 35 and the most upstream recording head 34a. That is, the downstream end of each first groove 321a is located between the first region A and the second region B (see FIG. 5). Accordingly, each first groove 321a extends (protrudes) to a position upstream of the most upstream recording head 34a (second region B) in the paper transport direction X. In other words, each first groove 321a does not reach the second region B (below the recording head 34).

  The through hole 322 in each first groove 321a is provided below the plate-like member 35 (in the first region A). Hereinafter, the through hole 322 in the first groove 321a is referred to as a first through hole 322a. Each first through hole 322a is located between the plate-like member 35 (first area A) and the most upstream recording head 34a (second area B) more than the most upstream recording head 34a (second area B). You may provide in the position close | similar to the plate-shaped member 35 (1st area | region A).

  According to such a configuration, the foreign matter recovery efficiency can be increased without increasing the suction force below the recording head 34. That is, since a suction force is generated mainly in each first through hole 322a by the first suction device 372a (see FIG. 6), the suction force of each first groove 321a can be increased. Accordingly, it is possible to generate a wind having a sufficient wind speed in the narrow space 351 to separate the foreign matter from the paper P.

  Further, each first groove 321 a does not reach below the recording head 34. Therefore, it is possible to suppress the suction force of each first groove 321 a from acting on the space below the recording head 34. That is, it is possible to suppress the occurrence of a flow of air (wind) having a high wind speed in the space below the recording head 34 due to the suction force of each first groove 321a.

  On the other hand, as shown in FIG. 9, for example, when each first groove 321a extends to the lower side of the most upstream recording head 34a, the suction force below the most upstream recording head 34a increases. When the suction force below the most upstream recording head 34a increases, foreign matter scatters under the most upstream recording head 34a, adheres to the nozzles of the most upstream recording head 34a, and nozzle clogging (no ink ejection) is likely to occur. Become.

  In the present embodiment, as shown in FIG. 8, the plurality of grooves 321 include a plurality of second grooves 321b. Each of the second grooves 321b extends toward the plate-like member 35 from below the most upstream recording head 34a to the outside of the most upstream recording head 34a. The upstream end of each second groove 321b in the paper transport direction X is located below the plate member 35 (first region). In other words, each second groove 321b extends from below the uppermost recording head 34a (second region B) to below the plate-like member 35 (first region A).

  The through-hole 322 in each second groove 321b is located between the plate-like member 35 (first area A) and the most upstream recording head 34a (second area B), more upstream than the plate-like member 35. It is provided in the position near. Hereinafter, the through hole 322 in the second groove 321b is referred to as a second through hole 322b. Each second through hole 322b may be provided below the uppermost recording head 34a (in the second region B).

  In this way, even if each second groove 321b extends to the lower part (first area A) of the plate-like member 35, the foreign matter recovery efficiency can be improved without increasing the suction force below the most upstream recording head 34a. it can. This is because a suction force is generated in each second through hole 322b mainly by the second suction device 372b (see FIG. 6). In addition, since a suction force is mainly generated by the second suction device 372b in each second through hole 322b, the suction force of each second groove 321b is weakened and below the most upstream recording head 34a (second region B). It is possible to suppress scattering of foreign matter at

  As the first through hole 322a is further away from the most upstream recording head 34a (second region B), the suction force below the plate-like member 35 is increased, and the foreign matter recovery efficiency is improved. Further, as the first through hole 322a is further away from the most upstream recording head 34a (second region B), the suction force of the first through hole 322a can be suppressed from acting on the space below the recording head 34. .

  Next, the operation of the recording unit 3 will be described with reference to FIGS. 1 to 8, 10, and 11. FIG. 10 is a diagram illustrating a state when the paper P enters the narrow space 351. Specifically, FIG. 10 shows a state in which the foreign matter m is peeled from the front end portion (left end portion in FIG. 10) of the paper P when the paper P enters the narrow space 351. FIG. 11 is a diagram illustrating a state when the paper P is separated from the narrow space 351. Specifically, FIG. 11 shows a state where the foreign matter m is peeled from the rear end portion (the right end portion in FIG. 11) of the paper P when the paper P leaves the narrow space 351.

  When recording an image on the paper P, the drive roller 312 is driven to rotate, and the first suction device 372a and the second suction device 372b are driven. As a result, the conveyor belt 310 rotates and a negative pressure is generated in the pressure chamber 374. Due to this negative pressure, a suction force is generated in each groove 321 through each through hole 322. A suction force is generated in each suction hole 311 of the rotating conveyor belt 310 via each groove 321. Specifically, a suction force is generated in each suction hole 311 (each suction hole 311 positioned on the transport plate 32) located at a location supported by the transport plate 32 in the rotating transport belt 310. As a result, air is sucked into the pressure chamber 374 through the transport plate 32 and the transport belt 310. In addition, air flows into the narrow space 351 from the first hole 361 and the second hole 362.

  The paper P sent to the recording unit 3 by the registration roller pair 44 is guided onto the transport belt 310 by the suction roller 316. At this time, the paper P is preferably guided to the transport belt 310 so that the center of the paper P in the paper width direction coincides with the center of the transport belt 310 in the paper width direction. The paper P covers a part of the transport belt 310. In other words, a part of the plurality of suction holes 311 is covered. As a result, a suction force (negative pressure) acts on the paper P, and the paper P is attracted to the transport belt 310. Then, the paper P is transported in the paper transport direction X as the transport belt 310 rotates.

  The sheet P passes through the first area A (below the plate-like member 35) by the transport belt 310 and then passes through the second area B (below the recording head 34). When the paper P enters the lower part of the plate member 35, that is, into the narrow space 351, the front end portion of the paper P is exposed to the wind indicated by the arrow D1, as shown in FIG. The wind indicated by the arrow D1 is a flow of air that flows from the first hole 361 toward the narrow space 351, and blows from the upstream side to the downstream side in the paper transport direction X (to the left in FIG. 10). The foreign matter m adhering to the front end portion of the paper P is peeled off from the paper P by this wind. The peeled foreign matter m is guided from the suction hole 311 located below the plate-like member 35 to the groove 321 located below the plate-like member 35 and is introduced into the pressure chamber 374 via the corresponding through-hole 322. It is burned. Then, it passes through the pressure chamber 374 and mainly passes through the first suction device 372a and the first duct 373a and is discharged to the outside.

  Further, when the paper P leaves the narrow space 351, as shown in FIG. 11, the rear end portion of the paper P is exposed to the wind indicated by the arrow D2. The wind indicated by the arrow D2 is a flow of air that flows from the second hole 362 toward the narrow space 351, and blows from the downstream side to the upstream side in the paper transport direction X (to the right in FIG. 11). The foreign matter m adhering to the rear end portion of the paper P is peeled off from the paper P by this wind. The peeled foreign matter m is guided from the suction hole 311 located below the plate-like member 35 to the groove 321 located below the plate-like member 35 and is introduced into the pressure chamber 374 via the corresponding through-hole 322. It is burned. Then, it passes through the pressure chamber 374 and mainly passes through the first suction device 372a and the first duct 373a and is discharged to the outside.

  When the paper P passes through the second area B, each part of the paper P is continuously conveyed to positions facing the four types of recording heads 34a, 34b, 34c, and 34d. During this time, ink droplets of each color are ejected toward the paper P from the four types of recording heads 34a, 34b, 34c, and 34d. As a result, an image is recorded on the paper P.

  According to the first embodiment described above, the adhesion of foreign matter to the nozzles of the recording head 34 can be suppressed with a simple configuration.

  Further, the suction force of the groove 321 disposed below the plate-like member 35 is larger than the suction force of the groove 321 disposed below the recording head 34. According to such a configuration, the foreign matter recovery efficiency can be increased.

  Further, since each first groove 321a does not reach the second region B (below the recording head 34), the foreign matter recovery efficiency can be increased without increasing the suction force below the recording head 34.

  Further, at least the lower surface of the plate-like member 35 is made of a conductor. According to such a configuration, it is difficult for the charged paper powder to adhere to the plate-like member 35. In addition, by grounding the conductor constituting the plate-like member 35, the charged paper powder is less likely to adhere to the plate-like member 35.

  In addition, since the first hole 361 and the second hole 362 are formed in the head base 36, air can flow smoothly into the narrow space 351.

  Further, since the suction unit 37 includes two independent suction devices 372 a and 372 b, the suction force of the groove 321 disposed below the plate-like member 35 is applied to the groove 321 disposed below the recording head 34. It can be easily made larger than the suction force. Therefore, the foreign matter recovery efficiency can be easily increased. In addition, the suction force of the groove 321 disposed below the recording head 34 can be made smaller than the suction force of the groove 321 disposed below the plate-like member 35 without reducing the foreign matter collection efficiency. Therefore, the scattering of foreign matters below the recording head 34 can be easily suppressed.

  In the present embodiment, the case where the plate-like member 35 is fixed to the head base 36 is described. However, the plate-like member 35 is fixed to another fixing member provided in the apparatus housing 100. It may be a form. For example, the form which fixes the both ends of the sheet width direction of the plate-shaped member 35 to a fixing member may be sufficient. According to such a configuration, there is no member that obstructs the flow of air flowing into the narrow space 351 from the downstream side and the upstream side of the plate-like member 35 with respect to the paper transport direction X. The wind speed can be further increased. Therefore, paper dust can be more effectively removed.

  In the present embodiment, a case is described in which each second groove 321b extends from below the uppermost recording head 34a (second region B) to below the plate-like member 35 (first region A). However, the present invention is not limited to this. Hereinafter, another example of the positional relationship between the plate-like member 35 and the grooves 321 and the through holes 322 of the transport plate 32 will be described with reference to FIGS.

  FIG. 12 is a diagram illustrating another example 1 of the positional relationship between the plate-like member 35 and the grooves 321 and the through holes 322 of the transport plate 32. As shown in FIG. 12, the upstream end of each second groove 321b in the paper transport direction X may be located between the plate-like member 35 and the most upstream recording head 34a. That is, the upstream end of each second groove 321b may be located between the first region A (see FIG. 5) and the second region B (see FIG. 5). Therefore, each second groove 321b may extend (project) to a position downstream of the first region A (plate-like member 35) with respect to the paper transport direction X. In other words, each second groove 321b may not reach the lower part of the plate-like member 35 (first area A).

  According to such a configuration, since each second groove 321b does not reach below the plate-like member 35, the suction force in the narrow space 351 can be increased compared to the configuration shown in FIG. Efficiency can be further increased.

  FIG. 13 is a diagram illustrating another example 2 of the positional relationship between the plate-like member 35 and the grooves 321 and the through holes 322 of the transport plate 32. In the configuration shown in FIGS. 8 and 12, the lengths of the grooves 321 in the paper transport direction X are equal to each other. On the other hand, in the configuration shown in FIG. 13, the lengths of the first grooves 321a in the paper transport direction X are not the same. Specifically, there are a first groove 321a having a relatively long length in the paper transport direction X and a first groove 321a having a relatively short length in the paper transport direction X. In this way, by forming a plurality of types of first grooves 321a having different lengths in the paper transport direction X, the distance between the plate-like member 35 and the most upstream recording head 34a can be reduced, and the apparatus Miniaturization can be achieved.

  Further, in the configuration shown in FIG. 13, the lengths of the second grooves 321b in the paper transport direction X are not the same. That is, there are a second groove 321b having a relatively long length in the paper transport direction X and a second groove 321b having a relatively short length in the paper transport direction X. In this way, by forming a plurality of types of second grooves 321b having different lengths in the paper transport direction X, the distance between the plate-like member 35 and the most upstream recording head 34a can be further reduced, and the apparatus Further downsizing can be achieved.

(Second Embodiment)
Hereinafter, with reference to the drawings, the second embodiment of the present invention will be described while referring to differences from the first embodiment. The second embodiment is different from the first embodiment in the arrangement of grooves 321 formed in the transport plate 32 and the positions of the through holes 322 formed in the transport plate 32.

  FIG. 14 is a view showing a groove 321 and a through hole 322 below the plate-like member 35 according to the second embodiment. In the second embodiment, only the first groove 321 a is disposed below the plate-like member 35. The first groove 321 a extends (projects) from the lower side of the plate-like member 35 to the downstream side of the plate-like member 35 in the paper transport direction X. Furthermore, in the second embodiment, the first groove 321 a extends (projects) from the lower side of the plate-like member 35 to the upstream side of the plate-like member 35 with respect to the paper transport direction X.

  The downstream end of each first groove 321a in the paper transport direction X is similar to the first groove 321a described in the first embodiment, and the plate member 35 (first area A) and the most upstream recording head 34a (first). 2 region B). In other words, each first groove 321a does not reach the second region B (below the recording head 34).

  In the second embodiment, two first through holes 322a are provided in each first groove 321a. One of the two first through holes 322a is provided below an upstream end 35a (hereinafter referred to as an upstream end 35a) of the plate-like member 35 with respect to the paper transport direction X. That is, one of the two first through holes 322 a faces the upstream end 35 a of the plate member 35. The other of the two first through holes 322a is provided below an end portion 35b on the downstream side of the plate-like member 35 with respect to the paper transport direction X (hereinafter referred to as a downstream end portion 35b). That is, the other of the two first through holes 322 a faces the downstream end 35 b of the plate-like member 35.

  According to such a configuration, the suction force immediately below the upstream end 35a and the downstream end 35b of the plate-like member 35 can be increased. As a result, the curled paper P becomes difficult to contact the plate-like member 35.

  The curl is generated, for example, when the sheet P is wet with water and one side of the sheet P extends. Therefore, the higher the environmental humidity, the easier the curl. Further, the distortion of the paper P due to curling becomes particularly large at the four corners of the paper P. This is because, at the four corners of the paper P, distortion due to curl in the paper transport direction X and distortion due to curl in the paper width direction overlap. Therefore, if the suction force immediately below the upstream end 35a and the downstream end 35b of the plate-like member 35 is weak, the four corners of the paper P come into contact with the plate-like member 35 when the curled paper P is conveyed. It becomes easy. When the paper P comes into contact with the plate-like member 35, there is a possibility that a foreign substance such as paper dust attached to the plate-like member 35 adheres (moves) to the paper P. Further, when the paper P contacts the plate-like member 35, there is a possibility that paper jam (paper jam) may occur in the narrow gap space 351 (see FIG. 6).

  For example, in the configuration shown in FIGS. 15A and 15B, the suction force immediately below the upstream end 35a and the downstream end 35b of the plate-like member 35 is reduced. Specifically, in the configuration shown in FIGS. 15A and 15B, the groove 321 disposed below the plate-like member 35 has an upstream side of the plate-like member 35 with respect to the sheet conveyance direction X and It is not stretched (projected) on any downstream side. In addition, one through hole 322 is provided in the groove 321, and the through hole 322 is located immediately below the center of the plate-like member 35 in the paper transport direction X. In contrast to such a configuration, when the curled paper P is conveyed, when the paper P enters the lower part of the plate-like member 35 (the first area A shown in FIG. 5), the corner on the front end side of the paper P is It is easy to contact the plate-like member 35 (FIG. 15A). Further, when the curled paper P is separated from the lower side (first area A) of the plate-like member 35, the corner on the rear end side of the paper P easily comes into contact with the plate-like member 35 (FIG. 15B).

  Further, for example, in the configuration shown in FIGS. 16A and 16B, the suction force immediately below the upstream end 35 a of the plate member 35 is relatively large, while the downstream side of the plate member 35 is. The suction force directly below the end 35b is relatively small. Specifically, in the configuration shown in FIGS. 16A and 16B, the groove 321 disposed below the plate-like member 35 is upstream of the plate-like member 35 with respect to the paper transport direction X. It is stretched (protruded) only. Further, one through hole 322 is provided in the groove 321, and the through hole 322 is located immediately below the upstream end 35 a of the plate-like member 35 (opposite the upstream end 35 a). According to this configuration, even when the curled paper P is transported, it is difficult for the paper P to contact the plate-like member 35 when the paper P enters below the plate-like member 35 (first region A). (FIG. 16A). However, when the curled paper P is separated from the lower side (first region A) of the plate-like member 35, the corner on the rear end side of the paper P easily comes into contact with the plate-like member 35 (FIG. 16B).

  On the other hand, in the configuration shown in FIGS. 17A and 17B, the suction force immediately below the upstream end 35 a of the plate member 35 is relatively small, while the downstream side of the plate member 35 is. The suction force directly below the end 35b becomes relatively large. Specifically, in the configuration shown in FIGS. 17A and 17B, the groove 321 disposed below the plate-like member 35 is downstream of the plate-like member 35 with respect to the paper transport direction X. It is stretched (protruded) only. Further, one through hole 322 is provided in the groove 321, and the through hole 322 is located immediately below the downstream end 35 b of the plate-like member 35 (opposite the downstream end 35 b). According to this configuration, even when the curled paper P is transported, it is difficult for the paper P to come into contact with the plate-like member 35 when the paper P moves away from below the plate-like member 35 (first region A) ( FIG. 17B). However, when the curled paper P enters the lower side of the plate-like member 35 (first area A), the corner on the front end side of the paper P is likely to come into contact with the plate-like member 35 (FIG. 17A).

  In contrast to the configuration shown in FIGS. 15 to 17, in this embodiment, as shown in FIGS. 18A and 18B, each first groove 321 a is transported from below the plate-like member 35. The film extends (projects) upstream and downstream of the plate member 35 with respect to the direction X. In addition, two first through holes 322a are provided in the first groove 321a. One of the two first through holes 322a is located immediately below the upstream end 35a of the plate-like member 35 (opposite the upstream end 35a). The other of the two first through holes 322a is located immediately below the downstream end 35b of the plate-like member 35 (opposite the downstream end 35b). Accordingly, the suction force increases at any of the upstream side end portion 35a and the downstream side end portion 35b of the plate-like member 35. Therefore, even when the curled paper P is transported, it is difficult for the paper P to contact the plate-like member 35 when the paper P enters below the plate-like member 35 (first area A) (FIG. 18 ( a)). Further, even when the curled paper P is separated from the lower side (first area A) of the plate-like member 35, a problem that the paper P contacts the plate-like member 35 hardly occurs (FIG. 18B). In other words, the curled paper P can be reliably adsorbed to the transport belt 310 (see FIG. 6).

  Next, another example 1 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment will be described with reference to FIG. FIG. 19 is a diagram illustrating another example 1 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment.

  In the configuration shown in FIG. 19, a plurality of first grooves 321 a and a plurality of third grooves 321 c are formed below the plate-like member 35. Each first groove 321a extends (projects) only from the lower side of the plate-like member 35 to the downstream side of the plate-like member 35 in the paper transport direction X, as in the first embodiment. Each of the third grooves 321 c extends (projects) only from the lower side of the plate-like member 35 to the upstream side of the plate-like member 35 in the paper transport direction X. The first grooves 321a and the third grooves 321c are alternately arranged along the paper width direction.

  In the configuration shown in FIG. 19, one through hole 322 (first through hole 322a) is provided in each first groove 321a as in the first embodiment. One through hole 322 is also provided in each third groove 321c. Hereinafter, the through hole 322 in the third groove 321c is referred to as a third through hole 322c. Each first through hole 322 a is provided below the downstream end portion 35 b of the plate-like member 35. That is, each first through hole 322 a faces the downstream end portion 35 b of the plate-like member 35. Each of the third through holes 322c is provided below the upstream end portion 35a of the plate-like member 35. That is, each third through-hole 322 c faces the upstream end 35 a of the plate-like member 35.

  Even with such a configuration, the suction force immediately below both the upstream end 35a and the downstream end 35b of the plate-like member 35 is increased. As shown in FIG. 14, when two through holes 322 (first through holes 322a) are opened in one groove 321 (first groove 321a), one through hole 322 is formed in one groove 321. In order to obtain a suction force equivalent to the suction force of the groove 321 generated when opening, it is necessary to increase the suction force of the first suction device 372a (see FIG. 6). That is, it is necessary to increase the power supplied to the first suction device 372a. In contrast, in the configuration shown in FIG. 19, one through hole 322 (first through hole 322a and third through hole 322c) is opened in one groove 321 (first groove 321a and third groove 321c). Therefore, the configuration shown in FIG. 19 can reduce the suction force of the first suction device 372a compared to the configuration shown in FIG. In other words, according to the configuration shown in FIG. 19, compared with the configuration shown in FIG. 14, the curled paper P is transferred to the transport belt 310 (see FIG. 6) without increasing the suction force of the first suction device 372a. Adsorption can be ensured.

  Next, another example 2 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment will be described with reference to FIG. FIG. 20 is a diagram illustrating another example 2 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment.

  In the configuration shown in FIG. 20, the number of the third grooves 321c is larger than that of the first grooves 321a. According to such a configuration, the number of through holes 322 (third through holes 322 c) immediately below the upstream end 35 a of the plate-like member 35 is increased, so that the curled paper P is reliably adsorbed to the transport belt 310. be able to. Although the suction force just below the downstream end 35b of the plate-like member 35 is slightly reduced, the sheet P is once sucked by the conveyance belt 310 just below the upstream end 35a of the plate-like member 35. The curled paper P can be adsorbed to the transport belt 310 with a lower suction force directly below the downstream end 35b of the plate-like member 35 than immediately below the upstream end 35a of the plate-like member 35.

  Next, another example 3 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment will be described with reference to FIG. FIG. 21 is a diagram illustrating another example 3 of the groove 321 and the through hole 322 below the plate-like member 35 according to the second embodiment.

  FIG. 21 shows an example of each size of the paper P on which the transport plate 32 (see FIG. 6) can be guided (that is, the ink jet recording apparatus 1 can record). Specifically, in FIG. 21, “12 × 18” indicates the sheet P when the short side of the sheet P having a size of “12 inches × 18 inches” (so-called A3 Nobi) is orthogonal to the sheet transport direction X. Indicates the position of the end of the region through which the That is, it indicates a position through which the four corners of the sheet P having a size of “12 inches × 18 inches” pass. Similarly, “A3” indicates a position where the four corners of the paper P pass when the short side of the A3 size paper P is orthogonal to the paper transport direction X. “A4R” indicates a position through which the four corners of the paper P pass when the short side of the A4 size paper P is orthogonal to the paper transport direction X.

  In the configuration shown in FIG. 21, third grooves 321c are provided inside and outside the positions where the four corners of each size of paper P pass (the end of the region through which the paper P passes). In other words, the third groove 321c is provided across the end of the area through which each size of paper P passes. According to such a configuration, the four corners of the paper P where the distortion due to curling is particularly large can be efficiently adsorbed to the transport belt 310 (see FIG. 6).

  According to the second embodiment described above, the foreign matter is separated from the paper P in the first area A (see FIG. 5) before the paper P enters the second area B (see FIG. 5). it can. Furthermore, according to the second embodiment, it is possible to suppress contact (collision) with the plate-like members 35 at the four corners of the paper P caused by curling and paper jam in the narrow space 351 (see FIG. 6). .

  In the configuration shown in FIG. 14, only the first grooves 321 a extending respectively upstream and downstream of the plate-like member 35 with respect to the paper transport direction X are arranged below the plate-like member 35. The invention is not limited to this. A first groove 321a extending upstream and downstream of the plate-like member 35 with respect to the paper transport direction X, and a first groove extending only downstream of the plate-like member 35 with respect to the paper transport direction X 321a (see, for example, FIG. 19) and the third groove 321c (see, for example, FIG. 19) may be formed on one transport plate 32.

  In the configurations shown in FIGS. 19 to 21, at least one first groove 321a and at least one third groove 321c are alternately arranged along the paper width direction, but the present invention is not limited to this. Not. For example, as shown in FIG. 22, the first groove 321 a and the third groove 321 c may be formed in the same row along the paper transport direction X below the plate-like member 35. FIG. 22 shows the arrangement of the grooves 321 shown in FIG. 8 of the first embodiment, just like the second embodiment, directly below the upstream end 35a and the downstream end 35b of the plate-like member 35 (upstream end). The structure which provided the through-hole 322 (the 1st through-hole 322a and the 3rd through-hole 322c) in the position which opposes the part 35a and the downstream end part 35b is shown.

  The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the above-described embodiment, and can be implemented in various modes without departing from the gist thereof.

  For example, in the embodiment of the present invention, the mode in which the transport belt 310 transports the paper P has been described. For example, the paper P may be transported by a plurality of transport rollers. In this case, it is preferable to suck air from between adjacent conveyance rollers.

  In the embodiment of the present invention, the form in which the narrow space 351 is formed by the plate-like member 35 has been described. However, the form in which the narrow space 351 is formed by other methods may be used. For example, the head base 36 may be formed so as to protrude toward the conveyance belt 310 on the upstream side of the recording head 34 with respect to the sheet conveyance direction X to form the narrow space 351. In this case, the structure can be simplified.

  Alternatively, the narrow space 351 may be formed by a belt stretched around two rollers instead of the plate member 35. Specifically, an endless belt stretched between a driving roller and a driven roller can be used as the space forming member. In this case, it is preferable to arrange the driving roller and the driven roller so that the surface of the endless belt facing the conveyance belt 310 or the conveyance plate 32 is parallel to the conveyance belt 310 or the conveyance plate 32. According to such a configuration, even when paper dust adheres to the endless belt, the endless belt is driven to rotate so that the surface of the endless belt to which paper dust does not adhere is conveyed to the conveyor belt 310 or the conveyor plate. 32. Therefore, it is possible to reduce the frequency with which the serviceman or the like removes the paper dust adhering to the endless belt.

  In the embodiment of the present invention, the case where the first hole 361 is formed in the head base 36 has been described, but the present invention is not limited to this. The length of the head base 36 in the paper transport direction X may be shortened, and the gap between the upstream end of the head base 36 in the paper transport direction X and the suction roller 316 may be increased.

  In the embodiment of the present invention, the case where the transport plate 32 and the box-shaped member 371 are separate members has been described. However, the transport plate 32 and the box-shaped member 371 may be integrally formed. In this case, the negative pressure leak from the pressure chamber 374, that is, the inflow of air into the pressure chamber 374 from the gap between the transport plate 32 and the box-shaped member 371 can be prevented.

  Moreover, although embodiment of this invention demonstrated the case where a negative pressure was generated in one pressure chamber 374 by two independent suction devices 372a and 372b, this invention is not limited to this. For example, as shown in FIG. 23, the suction part 37 may be provided with two pressure chambers 374a and 374b.

  FIG. 23 is a diagram illustrating another example 1 of the configuration of the recording unit 3. In the configuration shown in FIG. 23, the suction portion 37 further includes a partition plate 376. The partition plate 376 is erected in a space defined by the transport plate 32 and the box-shaped member 371. Specifically, the partition plate 376 divides a space defined by the transport plate 32 and the box-shaped member 371 into two to form two pressure chambers 374a and 374b.

  As shown in FIG. 24, the partition plate 376 is provided between the first through hole 322a and the second through hole 322b. FIG. 24 is a diagram illustrating the position of the partition plate 376. Specifically, FIG. 24 shows the position of the partition plate 376 provided for the configuration shown in FIG. 8 of the first embodiment. As shown in FIG. 24, by providing the partition plate 376, the space defined by the transport plate 32 and the box-shaped member 371 is divided into a pressure chamber 374a in which the suction force of the first suction device 372a acts, and a second suction device. It can be divided into a pressure chamber 374b on which the suction force of 372b acts. Therefore, the suction force in the narrow space 351 and the suction force in the space below the recording head 34 can be individually adjusted. As a result, it is easy to make the suction force in the narrow space 351 larger than the suction force in the space below the recording head 34.

  In the embodiment of the present invention, the case where two independent suction devices 372a and 372b are used in order to make the suction force in the narrow space 351 larger than the suction force in the space below the recording head 34 will be described. However, the present invention is not limited to this.

  For example, as shown in FIG. 25, only one suction device 372 may be used. FIG. 25 is a diagram illustrating another example 2 of the configuration of the recording unit 3. As shown in FIG. 25, when only one suction device 372 is used, the depth H1 of the pressure chamber 374 below the plate-like member 35 is set larger than the depth H2 of the pressure chamber 374 below the recording head 34. To do. A suction device 372 is disposed below the plate-like member 35. Even with such a configuration, the suction force in the narrow space 351 can be made larger than the suction force in the space below the recording head 34.

  Alternatively, more than two suction devices may be used. For example, two suction devices may be disposed below the plate-like member 35, and one suction device may be disposed below the recording head 34. That is, the number of suction devices arranged below the plate-like member 35 may be larger than the number of suction devices arranged below the recording head 34. According to such a configuration, equal power can be supplied to each suction device, and the power supply system can be simplified.

  In the embodiments of the present invention, the case where the present invention is applied to an inkjet recording apparatus capable of recording an image in full color has been described. However, the present invention can also be applied to an inkjet recording apparatus that records an image in monochrome. .

  Note that the items described in the embodiment of the present invention can be combined as appropriate.

  The present invention can be used for an electronic apparatus capable of recording an image on a recording medium by ejecting ink droplets.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 3 Recording part 31 Conveying part 310 Conveying belt 311 Suction hole 32 Conveying plate 321 Groove 321a 1st groove 321b 2nd groove 321c 3rd groove 322 Through-hole 322a 1st through-hole 322b 2nd through-hole 322c 3rd through-hole Hole 34, 34a to 34d Recording head 35 Plate member 351 Narrow space 37 Suction part 372a First suction device 372b Second suction device 374 Pressure chamber P Paper

Claims (10)

An inkjet recording apparatus that ejects ink droplets and records an image on a recording medium,
A plurality of grooves extending in the first direction in which the recording medium is conveyed, a through hole opening in the groove and communicating with the groove, and the plurality of grooves in the first direction and the first direction A guide member for guiding the recording medium from the first area to the second area, and a support surface formed along a second direction perpendicular to
A transport unit that transports the recording medium from the first region to the second region along the support surface;
A suction part for generating a suction force in the groove through the through hole;
A space forming member that faces the support surface in the first region and forms a foreign matter recovery space with the support surface;
A recording head that discharges the ink droplets to the recording medium conveyed to the second region, facing the support surface in the second region;
The plurality of grooves include a plurality of first grooves extending from the first region to a position upstream of the second region with respect to the first direction,
The ink jet recording apparatus, wherein the through hole in the first groove is provided at a position closer to the first area than the second area, or in the first area.   2. The inkjet recording apparatus according to claim 1, wherein the plurality of first grooves include a plurality of types of the grooves having different lengths in the first direction. The plurality of grooves include a plurality of second grooves extending from the second region to a position downstream of the first region with respect to the first direction,
3. The ink jet recording apparatus according to claim 1, wherein the through hole in the second groove is provided at a position closer to the second area than the first area or in the second area.   The inkjet recording apparatus according to claim 3, wherein the plurality of second grooves include a plurality of types of the grooves having different lengths in the first direction.   The ink jet recording apparatus according to claim 1, wherein the suction force in the first region is larger than the suction force in the second region. The first groove extends from the first region to the upstream side and the downstream side of the first region with respect to the first direction,
The two through holes are provided in the first groove at positions facing the upstream end and the downstream end of the space forming member in the first direction, respectively. The inkjet recording apparatus according to any one of 5. The plurality of grooves include a plurality of third grooves extending from the first region to the upstream side of the first region with respect to the first direction,
The through hole in the first groove is provided at a position facing the downstream end of the space forming member in the first direction;
The inkjet according to any one of claims 1 to 5, wherein the through hole in the third groove is provided at a position facing an upstream end of the space forming member in the first direction. Recording device.   The inkjet recording apparatus according to claim 7, wherein at least one of the first grooves and at least one of the third grooves are alternately arranged along the second direction.   The inkjet recording apparatus according to claim 8, wherein the number of the third grooves is larger than the number of the first grooves.   The said 3rd groove | channel is provided in the inner side and the outer side of the edge of the area | region through which the said to-be-recorded medium of each size which the said guide member can guide, respectively. Inkjet recording device.

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