JP5211908B2 - Image recording device - Google Patents

Description

  The present invention relates to an image recording apparatus for recording an image.

  Conventionally, when ink is ejected from a recording head of a printer as an image recording apparatus, most of the ink lands on a recording medium as ink droplets, but a part of the ink remains in the atmosphere as a minute ink mist. For example, the ink mist may adhere to the conveyance belt of the recording medium, and the recording medium is placed on the area where the ink mist adheres, and the back surface of the recording medium may be stained. Therefore, Patent Document 1 discloses a printer having a mist collection unit that includes a duct, a fan that sucks ink mist in the duct, and a filter that collects ink mist, and sucks ink mist discharged from the recording head. Have been described. In this printer, the suction portion of the duct is disposed on the downstream side in the conveyance direction of the recording head, and the ink mist is sucked from the suction portion and collected by the filter as the fan rotates.

Japanese Patent Laying-Open No. 2005-271314 (FIG. 1)

  However, the printer described in Patent Document 1 includes a mist collecting unit only for the purpose of sucking ink mist, and the number of parts increases.

  Accordingly, an object of the present invention is to provide an image recording apparatus in which the number of parts is reduced.

  An image recording apparatus according to the present invention includes a recording head that discharges liquid droplets to record an image on a recording medium, and a medium suction having a plurality of first holes that are opposed to the recording head and suck the recording medium. A transport belt for transporting the recording medium adsorbed in the medium suction area in the transport direction, and a plurality of first holes, and a mist suction area in which a second hole for sucking mist is formed. And a decompression device for generating a flow of air that passes toward the inside of the conveyor belt in the second hole. A virtual unit area in which the length in the transport direction is equal to the distance between the two first holes adjacent to each other in the transport direction and the length in the direction perpendicular to the transport direction is equal to the width of the transport belt. The maximum value of the total opening area of the second holes in the unit area when moved in the mist suction area is within the unit area when the unit area is moved in the medium adsorption area. It is larger than the maximum value of the total opening area of the certain first hole.

  According to the image recording apparatus of the present invention, the decompression device used for adsorbing the recording medium to the medium adsorbing area of the conveying belt can also be used for sucking mist. Therefore, it is not necessary to newly provide a mist suction means, and the number of parts can be reduced. Further, since the maximum value of the total opening area per unit area of the second hole of the mist suction area is larger than the maximum value of the total opening area per unit area of the first hole of the medium adsorption area, the mist is effectively prevented. Can be aspirated.

  The diameter of the second hole formed in the mist suction area is preferably larger than the diameter of the first hole formed in the medium adsorption area. According to this, compared with the case where the total opening area is increased by increasing the number of the second holes, it is possible to lengthen the distance between the two adjacent second holes, so that the kinking of the conveyor belt can be reduced.

  Furthermore, the diameter of the second hole is equal to or less than the diameter of the first hole, and the number of the second holes per row along the direction perpendicular to the transport direction formed in the mist suction region is: More than the number of the first holes per row along the direction perpendicular to the transport direction formed in the medium adsorption region, the total opening area of the second holes per row is the one row It is preferable that it is larger than the total opening area of the first hole. According to this, compared with the case where the diameter of the second hole is increased to increase the total opening area, it is difficult for a piece of paper with a torn recording medium to enter the second hole.

  In addition, between the medium adsorbing region and the mist suction region of the transport belt, two first adjacent to the transport direction along the circumferential direction of the transport belt in the entire width of the transport belt. It is preferable that the area | region where an opening area is zero is formed over the length longer than the distance between holes. According to this, the image quality is improved because it is hardly affected by the airflow caused by the mist suction during the recording operation.

  The total opening area of the second holes in the mist suction area is preferably larger than the total opening area of the plurality of first holes in the medium adsorption area. According to this, since the total opening area of the second holes in the mist suction area is larger than the total opening area of the first holes in the medium adsorption area, a large amount of mist can be sucked.

  Further, the apparatus further comprises control means for controlling the transport belt and the pressure reducing device, the control means facing the mist suction area and the recording head in a state where the pressure reducing device is operated, and It is preferable to stop the travel of the conveyor belt. According to this, mist remaining in the atmosphere can be sucked in a state in which the traveling of the conveyor belt is stopped after the recording operation is completed.

<First Embodiment>
Hereinafter, a preferred first embodiment of the present invention will be described with reference to the drawings. This embodiment is an example in which the present invention is applied to an ink jet printer that records characters, images, and the like by ejecting ink onto paper.

  FIG. 1 is a schematic configuration diagram of an ink jet printer according to a first embodiment of the present invention. FIG. 2 is a plan view of the sheet suction area of the conveyor belt shown in FIG. FIG. 3 is a plan view of a mist suction region of the conveyor belt shown in FIG.

  As shown in FIG. 1, an ink jet printer 1 that is an image recording apparatus is a color ink jet printer having four ink jet heads 2 and a belt conveying device 3. The ink jet printer 1 has a control unit 60 (see FIG. 4) for controlling the ink jet printer 1.

  The four inkjet heads 2 are arranged side by side along the conveyance direction (arrow direction in FIG. 1) of the paper P that is a recording medium, corresponding to the four color inks (magenta, yellow, cyan, and black). Yes. That is, the inkjet printer 1 is a line printer.

  The four inkjet heads 2 are long in the width direction (perpendicular to the paper surface in FIG. 1) parallel to the surface moving in the transport direction of the paper P and in the width direction (perpendicular to the paper surface in FIG. 1) of the outer peripheral surface 8a of the transport belt 8 described later. It has a rectangular parallelepiped shape. The bottom surface of the inkjet head 2 is opposed to an outer peripheral surface 8a of a conveyance belt 8 described later.

  The four inkjet heads 2 eject ink of each color from nozzles (not shown) toward the upper surface of the sheet P when the sheet P conveyed on the outer peripheral surface 8a of the sheet adsorption area 20 described later passes immediately below. Thus, a desired color image is recorded on the paper P.

  The belt conveyance device 3 includes a paper feeding unit 11 on the left side in FIG. 1 and a paper discharge unit 12 on the right side in FIG. 1, and the paper P is fed from the paper feeding unit 11 toward the paper discharge unit 12. Transport in the transport direction. A pair of feed rollers 9 a and 9 b that convey the paper P while sandwiching the paper P are disposed immediately downstream of the paper feed unit 11. The paper P is fed from left to right in FIG. 1 by the pair of feed rollers 9a and 9b.

  The belt conveying device 3 is wound around a pair of belt rollers 13 and 14 having rotation axes parallel to each other and the pair of belt rollers 13 and 14, and the pair of belt rollers 13 and 14 is rotated. And an endless conveyance belt 8 that conveys a sheet P placed on an outer peripheral surface 8a of a sheet suction area 20 to be described later in the conveyance direction.

  The conveyor belt 8 has a paper suction area 20 and a mist suction area 21. As shown in FIG. 2, the sheet suction region 20 is longer than the length in the conveyance direction of the sheet P along the circumferential direction of the conveyance belt 8 in the entire width in the width direction of the conveyance belt 8, and from the conveyance direction length of the space A described later. Only a short region is formed. In the sheet suction area 20, a plurality of rows of holes 20a (first holes) arranged in the width direction are arranged in the transport direction. The paper P is placed on the outer peripheral surface 8a of the paper suction area 20 and is transported in the transport direction.

  As shown in FIG. 3, the mist suction area 21 is formed in the entire width in the width direction of the conveyance belt 8 by the same length as the sheet suction area 20 along the circumferential direction of the conveyance belt 8. In the mist suction region 21, a plurality of rows of holes 21a (second holes) having a larger diameter than the holes 20a arranged at the same intervals as the holes 20a along the width direction are arranged in the transport direction at the same intervals as the holes 20a. Has been. That is, the total opening area of the holes 21 a in the mist suction area 21 is larger than the total opening area of the holes 20 a in the paper suction area 20. A hole 21a in the mist suction area 21 sucks mist remaining in the atmosphere including the periphery of the inkjet head 2 by rotation of a rotary blade of a rotary fan 5 described later. At this time, since the total opening area of the holes 21a in the mist suction area 21 is larger than the total opening area of the holes 20a in the paper suction area 20, a large amount of mist can be sucked.

  Further, here, a virtual area in which the length in the transport direction is equal to the distance between two holes 20a adjacent in the transport direction and the length in the width direction is equal to the width of the transport belt 8 (in FIG. 2). The area indicated by diagonal lines is a unit area 22. At this time, the maximum value of the total opening area of the holes 21a in the unit area 22 when moved in the mist suction area 21 is within the unit area 22 when the unit area 22 is moved in the paper suction area 20. It is larger than the maximum value of the total opening area of the holes 20a.

  That is, since the maximum value of the total opening area per unit area 22 of the hole 21a in the mist suction area 21 is larger than the maximum value of the total opening area per unit area 22 of the hole 20a in the paper suction area 20, the mist In the suction area 21, mist can be effectively sucked compared to the paper suction area 20. At this time, the diameter of the hole 21a in the mist suction area 21 is made larger than the diameter of the hole 20a in the sheet suction area 20 to increase the total opening area of the holes 21a in the mist suction area 21, so that the mist suction area Compared with the case where the total opening area is increased by increasing the number of the 21 holes 21a, the distance between the two adjacent holes 21a can be increased, and the kinking of the transport belt 8 can be reduced.

  In addition, between the sheet suction area 20 and the mist suction area 21, the entire width of the conveyance belt 8 is longer than the distance between the two holes 20 a adjacent in the conveyance direction along the circumferential direction of the conveyance belt 8. A non-porous region having no opening area and having no holes is formed. In the present embodiment, since the non-perforated area is formed on the conveyance belt 8, the mist suction area 21 is located along the vertical direction when the paper suction area 20 faces the inkjet head 2. It is arranged at a position overlapping 20.

  The belt roller 13 is a driving roller that receives a driving force from a conveyance motor 74 (see FIG. 4) and rotates clockwise. The belt roller 14 is driven to rotate by the rotational force applied from the conveying belt 8 as the belt roller 13 rotates. The transport belt 8 travels in the transport direction as the pair of belt rollers 13 and 14 rotate.

  As the transport belt 8 travels, the four inkjet heads 2 face each other in the order of the sheet suction area 20, the non-hole area, the mist suction area 21, and the non-hole area. In this way, by forming a non-hole area between the paper suction area 20 and the mist suction area 21, the recording head is discharged from the inkjet head 2 due to the influence of air current due to mist suction on both sides in the transport direction. Since the ink flight direction is difficult to change, the image quality is improved.

  An encoder 15 (see FIG. 4) is provided on the rotating shaft of the belt roller 13. The encoder 15 detects the rotational position of the belt roller 13. Based on the rotational position of the belt roller 13 detected by the encoder 15, a position acquisition unit 64 described later acquires the positions of the paper suction area 20 and the mist suction area 21 formed on the conveyance belt 8 in the conveyance direction.

  The paper P sent out from the paper supply unit 11 by the feed rollers 9 a and 9 b is pressed against the outer peripheral surface 8 a of the paper suction area 20 of the transport belt 8 by the pressing roller 16 facing the belt roller 14. The sheet P pressed against the outer peripheral surface 8a by the pressing roller 16 is conveyed downstream in the conveying direction (to the right in FIG. 1) as the conveying belt 8 is driven by the clockwise rotation driving of the belt roller 13. Then, it is peeled from the outer peripheral surface 8 a by the peeling mechanism 17 immediately downstream of the conveying belt 8 and sent to the paper discharge unit 12.

  Returning to FIG. 1, in the inner region surrounded by the conveyor belt 8, the platen 19 and the two rotary fans 5 (in order from the top along the vertical direction (the direction in which the inkjet head 2 and the conveyor belt 8 face each other)) ( Pressure reducing device) is arranged.

  Further, a sealing plate that defines a space A in which the platen 19 and the two rotary fans 5 are accommodated in a part of the inner peripheral surface of the conveyor belt 8 in the inner region surrounded by the conveyor belt 8. 25 is arranged. The sealing plate 25 is formed with an opening for exposing the lower surfaces of the two rotary fans 5.

  The platen 19 has a width similar to the width of the conveyor belt 8, extends between the pair of belt rollers 13 and 14, and contacts the surface opposite to the outer peripheral surface 8 a of the conveyor belt 8. Thus, the conveyor belt 8 is supported. A plurality of holes (not shown) are formed in the platen 19.

  The rotary fan 5 has a substantially rectangular parallelepiped shape, and sucks air in the space A by rotating a rotary blade provided inside. Then, the pressure in the space A is reduced, and the air that passes through the holes 20a and 21a formed in the conveying belt 8 that defines the space A and the holes (not shown) of the platen 19 toward the space A. The flow of Then, the air that has flowed in is discharged from the lower surface of the rotary fan 5 through the opening of the sealing plate 25.

  When the sheet suction area 20 faces the inkjet head 2 as the transport belt 8 travels due to the air flow, the sheet P placed on the outer peripheral surface 8a of the paper suction area 20 is sucked to the outer peripheral surface 8a. When the mist suction area 21 faces the inkjet head 2 as the transport belt 8 travels, the mist remaining in the atmosphere is sucked from the hole 21 a in the mist suction area 21.

  Next, the control system of the inkjet printer 1 will be described with reference to FIG. FIG. 4 is a schematic block diagram showing a control configuration of the inkjet printer according to the first embodiment of the present invention. The control unit 60 included in the inkjet printer 1 includes a CPU (Central Processing Unit) that is an arithmetic processing device, a ROM (Read Only Memory) that stores a control program executed by the CPU and data used in the control program. A RAM (Random Access Memory) for temporarily storing data during program execution.

  As shown in FIG. 4, the control unit 60 includes a head control unit 61, a conveyance control unit 62, a belt roller control unit 63, a position acquisition unit 64, and a pressure reduction control unit 65.

  When the control unit 60 receives a print signal from the PC 80 (personal computer), the head control unit 61 controls the head drive circuit 71 to eject ink from the corresponding ink jet head 2 so that an image or the like is generated on the paper P. Let's record.

  When the control unit 60 receives a print signal from the PC 80, the transport control unit 62 drives the feed motor 72 to rotate both the feed rollers 9 a and 9 b, thereby attracting the paper P to the paper of the transport belt 8. The motor driver 73 is controlled so as to be supplied onto the outer peripheral surface 8 a of the region 20.

  The belt roller control unit 63 drives the conveyance motor 74 to rotate the belt roller 13 when the sheet P is supplied onto the outer peripheral surface 8a of the sheet adsorption region 20 of the conveyance belt 8 under the control of the conveyance control unit 62. As a result, the motor driver 75 is controlled so that the transport belt 8 travels and the paper P on the outer peripheral surface 8a is transported in the transport direction.

  The position acquisition unit 64 acquires positions related to the paper suction area 20 and the mist suction area 21 of the transport belt 8 from the rotational position of the belt roller 13 detected by the encoder 15. When the position acquisition unit 64 acquires that the paper suction area 20 of the transport belt 8 is positioned in the vicinity of the paper feed unit 11, the paper P is supplied by the transport control unit 62, so that the outer periphery of the paper suction area 20. The paper P is placed on the surface 8a.

  The decompression control unit 65 controls the motor driver 79 to drive the rotary motor 78 and rotate the rotary blades of the rotary fan 5 to decompress the space A.

  In the ink jet printer 1, the decompression control unit 65 rotates the rotary blades of the rotary fan 5 to depressurize the space A, so that the paper P that is sucked and transported by the outer peripheral surface 8 a of the paper suction region 20 is transported to the ink jet head 2. When passing underneath, the ink of each color is ejected from a nozzle (not shown) toward the upper surface of the paper P to record a desired color image on the paper P.

  In addition, when the recording operation on the paper P is completed and the recording operation on the next paper P is to be performed, the inkjet printer 1 before the paper P is placed on the paper suction area 20 of the traveling conveyor belt 8. Furthermore, the mist suction area 21 faces the inkjet head 2. At this time, as in the case of the adsorption of the paper P to the paper adsorption area 20, the state where the space A is depressurized by rotating the rotary blades of the rotary fan 5 by the adsorption pressure reduction control unit 65 is maintained. The ink jet printer 1 sucks mist remaining in the atmosphere including the periphery of the ink jet head 2 from the hole 21a in the mist suction area 21.

  Further, when the recording operation on the paper P is completed and there is no recording operation on the next paper P, the ink jet printer 1 causes the transport control unit 62 to run the transport belt 8 to move the mist suction area 21 to the ink jet head. The conveying belt 8 is stopped in a state of being opposed to 2. Then, the decompression control unit 65 rotates the rotating blades of the rotary fan 5 to reduce the pressure in the space A, so that the atmosphere including the surroundings of the inkjet head 2 from the hole 21a in the mist suction area 21 after the recording operation is completed. The remaining mist can be sucked.

  According to the inkjet printer 1 according to the first embodiment described above, the rotary fan 5 used for sucking the paper P to the paper suction area 20 of the transport belt 8 can also be used for sucking mist. Therefore, it is not necessary to newly provide a mist suction means, and the number of parts can be reduced.

Second Embodiment
Next, a second embodiment will be described. FIG. 5 is a plan view of a mist suction region of the conveyor belt according to the second embodiment. The second embodiment is the same as the first embodiment except that the mist suction area 21 of the conveyor belt 8 in the first embodiment is a mist suction area 221. Components similar to those in the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 5, the mist suction region 221 is formed along the circumferential direction of the transport belt 8 by the same length as the paper suction region 20 in the entire width of the transport belt 8. In the mist suction region 221, a plurality of rows of holes 221a having the same diameter as the holes 20a arranged at a smaller interval than the holes 20a along the width direction are arranged in the transport direction at the same intervals as the holes 20a.

  In other words, the number of holes 221a per row along the width direction formed in the mist suction region 221 is greater than the number of holes 20a per row along the width direction formed in the paper suction region 20. ing. The total opening area of the holes 221 a per row formed in the mist suction area 221 is larger than the total opening area of the holes 20 a per line formed in the paper suction area 20. The holes 221a in the mist suction area 221 can suck more mist remaining in the atmosphere including the periphery of the inkjet head 2 than the holes 20a in the paper suction area 20 by the rotation of the rotary blades of the rotary fan 5. . In addition, the diameter of the hole 221a in the mist suction region 221 of the second embodiment is larger than that of the hole 21a in the mist suction region 21 of the first embodiment to increase the total opening area. Is small, it becomes difficult for a piece of paper P torn to enter.

  Next, modified examples in which various modifications are added to the above-described embodiment will be described. In the first and second embodiments described above, the non-porous region is formed between the paper suction region and the mist suction region, but the non-porous region may not be formed.

  In the first and second embodiments described above, a plurality of rows of holes arranged in the width direction are arranged in the transport direction in the mist suction region, and the number of rows is formed in the sheet suction region. Although the number of holes formed is the same as the number of holes, the number of lines arranged in the transport direction may be one or any number of lines larger than that. Even if there is only one row, the position of the mist suction area in which the hole is formed is moved by the travel of the transport belt when the transport belt 8 travels, so that the mist remaining in the atmosphere can be sucked. it can. At this time, since the holes formed in the mist suction area can suck more mist than the holes formed in the paper suction area, the total opening area of the holes per unit area of the mist suction area However, it is necessary to be larger than the total opening area of the holes per unit area of the sheet suction area.

  Furthermore, the number of holes formed in the mist suction region is not limited to a plurality, and may be one or any number. At this time, since the holes in the mist suction area can suck more mist than the holes in the paper suction area, the total opening area of the holes per unit area of the mist suction area is more It must be larger than the total opening area of the holes per unit area of the region.

  In the first and second embodiments described above, the sheet adsorption region 20 is longer than the length in the conveyance direction of the sheet P along the circumferential direction of the conveyance belt 8 in the entire width of the conveyance belt 8. However, it may be formed over a region longer than the length of the space A in the transport direction. At this time, the holes 20 a in the sheet suction area 20 that are effective when the air in the space A is sucked by the rotary fan 5 are only the length in the transport direction of the space A. When the transport direction lengths of the space A are compared in the entire width of the transport belt 8, the total opening area of the holes 21 a in the mist suction area 21 is the total opening area of the holes 20 a in the paper suction area 20. Is bigger than.

  Furthermore, in the second embodiment described above, the diameter of the hole in the mist suction area is the same as the diameter of the hole in the paper suction area, but may be smaller than the diameter of the hole in the paper suction area. . At this time, the total opening area of the holes per row along the width direction formed in the mist suction region is larger than the total opening area of the holes per row along the width direction formed in the paper suction region. It only has to be.

  The present invention is not limited to the ink jet printer as in the above-described embodiment, and can be applied to various apparatuses as long as the apparatus is an image recording apparatus.

1 is a schematic configuration diagram of an inkjet printer according to a first embodiment of the present invention. FIG. 2 is a plan view of a sheet suction region of the conveyance belt illustrated in FIG. 1. It is a top view of the mist suction area | region of the conveyance belt shown in FIG. It is a schematic block diagram which shows the control structure of the inkjet printer which concerns on 1st Embodiment of this invention. It is a top view of the mist suction area | region of the conveyance belt which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Inkjet head 5 Rotating fan 8 Conveying belt 20 Paper adsorption | suction area | region 20a, 21a, 221a Hole 21,221 Mist suction area 22 Unit area 60 Control part

Claims (6)

A recording head that discharges droplets and records an image on a recording medium;
A medium adsorbing area formed with a plurality of first holes for adsorbing a recording medium facing the recording head; and a mist suction area formed with a second hole for sucking mist, A conveyance belt for conveying the recording medium adsorbed in the medium adsorption area in the conveyance direction;
A pressure reducing device that generates a flow of air that passes toward the inside of the conveyor belt in the plurality of first holes and the second holes, and
A virtual unit area in which the length in the transport direction is equal to the distance between the two first holes adjacent to each other in the transport direction and the length in the direction perpendicular to the transport direction is equal to the width of the transport belt. The maximum value of the total opening area of the second holes in the unit area when moved in the mist suction area is within the unit area when the unit area is moved in the medium adsorption area. An image recording apparatus characterized by being larger than a maximum value of a total opening area of the first hole.   The image recording apparatus according to claim 1, wherein a diameter of the second hole formed in the mist suction area is larger than a diameter of the first hole formed in the medium adsorption area. The diameter of the second hole is equal to or less than the diameter of the first hole,
The number of the second holes per row along the direction perpendicular to the transport direction formed in the mist suction region is one row along the direction perpendicular to the transport direction formed in the medium suction region. More than the number of the first holes per hit,
The total opening area of the second hole per the one column, the image recording apparatus according to claim 1, wherein greater than the total opening area of the first hole per the one column.   Between the medium adsorbing region and the mist suction region of the transport belt, between the two first holes adjacent to the transport direction along the circumferential direction of the transport belt in the entire width of the transport belt. The image recording apparatus according to claim 1, wherein a region having an opening area of zero is formed over a length longer than the distance.   The total opening area of the second holes in the mist suction area is larger than the total opening area of the plurality of first holes in the medium adsorption area. The image recording apparatus according to claim 1. A control means for controlling the conveyor belt and the pressure reducing device;
6. The image recording according to claim 5, wherein the control unit is configured to stop the traveling of the conveyance belt by causing the mist suction area and the recording head to face each other in a state in which the decompression device is operated. apparatus.

Images