JP5745245B2 - Inkjet recording device - Google Patents

Description

  The present invention relates to an ink jet recording apparatus.

  Conventionally, ink jet recording apparatuses have been used for recording images on various recording media. And the proposal regarding an inkjet recording device is made (for example, refer patent document 1, 2).

  Patent Documents 1 and 2 disclose ink jet recording heads. The ink jet recording heads of Patent Documents 1 and 2 include four recording element substrates H1100. According to Patent Documents 1 and 2, among the four recording element substrates H1100, the recording element substrate H1100a and the recording element substrate H1100c, and the recording element substrate H1100b and the recording element substrate H1100d are arranged in the same row in the ejection port array direction.

  According to Patent Document 1, a dummy substrate H1600 is formed between the recording element substrate H1100a and the recording element substrate H1100c, and between the recording element substrate H1100b and the recording element substrate H1100d. It arrange | positions so that it may become substantially the same height as a surface. The gaps between the substrates are processed so as not to cause a step by the sealing material H1304.

  According to Patent Document 2, a cooling element substrate H2000 in which cooling elements such as Peltier elements are formed between the recording element substrate H1100a and the recording element substrate H1100c, and between the recording element substrate H1100b and the recording element substrate H1100d, respectively. The recording element substrate is disposed so as to have substantially the same height as the ejection port forming surface of the recording element substrate. The gaps between the substrates are processed so as not to be stepped by the sealing material H1304.

  The applicant has also proposed an ink jet recording apparatus (see, for example, Patent Document 3). In the ink jet recording apparatus of Patent Document 3, the recording head unit is moved to a position facing the ejection ink processing unit, and only the selected ink ejection head pressurizes the ink in the sub tank to perform the ejection recovery process. Then, when the recording head unit is returned to the original recording position, the residual ink is wiped off by the cleaning processing unit and sucked and removed.

  In addition, various proposals have been made (see, for example, Patent Documents 4, 5, and 6). Patent Document 5 discloses that an FPC as a power supply member is joined to the upper surface of an actuator unit and pulled out in one of the main scanning directions. According to Patent Document 5, the FPC joined to the actuator unit is drawn upward along the side surface of the ink tank. A driver IC is installed on the FPC. In the FPC, a plurality of signal lines arranged along the extending direction of the FPC are formed, and the driver IC and the surface electrode (actuator unit) are electrically connected.

  Further, Patent Document 6 discloses that a recording apparatus including an ink jet recording head has a problem that ink droplets are likely to be misted because ink droplets fly as a very small amount of ink droplets. According to Patent Document 6, since this ink mist is floating in the apparatus, if it adheres to a carriage, a housing or the like, it can be a large ink droplet. If the ink droplets become large, the ink droplets may enter the gap between the recording head and the carriage due to capillary force or the like, and the recording head may be soiled.

JP 2007-22037 A JP 2007-22038 A JP 2009-208408 A Japanese Patent Laid-Open No. 7-227966 JP 2006-44196 A JP 2004-203060 A

  The recording (patterning) of an image using an ink jet recording apparatus can also use as a recording medium an industrial material such as a concrete block forming a block wall or an exterior material used as an outer wall of a building such as a house. By the way, industrial materials sometimes have variations in thickness in a direction perpendicular to the recording surface. In some cases, the recording surface may have large irregularities. Therefore, it is necessary to prevent the recording head from contacting the recording surface of the industrial material during recording. For this reason, the ink discharge surface in which the discharge ports (nozzles) are formed in the recording head and the recording surface of the industrial material are considerably separated in consideration of contact prevention. For example, the gap between the two is set in a state of being separated by about 5 mm to 10 mm or about several tens of mm.

  Here, if the distance between the ink ejection surface of the recording head and the recording surface is increased, the flying distance of the ink ejected from the recording head becomes longer. For this reason, the ink is easily misted by the satellite of the ejected ink and / or the breakup of the ink droplets.

  Ink mist adhering to the ink ejection surface can be removed by regular maintenance. By the way, the structure of the ink jet recording apparatus is complicated. Therefore, when floating ink mist adheres to various components such as a substrate installed on the top of the recording head, it may be difficult to maintain the components contaminated by the ink mist. Further, when ink mist adheres to various components such as a substrate, the ink causes corrosion on various components such as the substrate, which may shorten the life of the ink jet recording apparatus.

  An object of the present invention is to provide an ink jet recording apparatus capable of reducing contamination by ink mist.

One aspect of the present invention made in view of the above-described conventional problems is an ink jet recording apparatus that transports a recording medium, discharges ink onto the recording medium, and records an image, and a transport unit that transports the recording medium; A plurality of recording heads for ejecting ink onto the recording medium transported by the transport unit to record the image, a recording head support member connecting the plurality of recording heads, and a plurality of recording heads. The recording unit including a plurality of fasteners that fasten each of the recording head support members to the recording head support member, and the recording unit by the plurality of recording heads separated from the recording head support member and connected by the recording head support member Is fixed, and the gap between the recording unit and the recording surface of the recording medium conveyed by the conveying unit is 5 mm or more, and is set above the conveying surface of the conveying unit. A carriage that is, included in the control unit of the ink jet recording apparatus, and a control part which is installed on top of said recording unit which is fixed to the carriage, the recording head supporting member, the recording by the conveying unit A first recording head row by a plurality of first recording heads of the plurality of recording heads arranged at a first position in a medium conveying direction in a direction orthogonal to the conveying direction; and the first recording head Among the plurality of recording heads, the plurality of first recording heads are arranged in parallel with each other at a second position downstream in the transport direction from the first position in the transport direction. A first recording head support member for connecting a second recording head array formed by a plurality of second recording heads separate from the recording head, the second recording head array, and the second recording head Of the plurality of recording heads arranged in the orthogonal direction at a third position downstream in the transport direction from the second position in the transport direction. A second recording head support member that connects a recording head and a third recording head row of a plurality of third recording heads that are separate from the plurality of second recording heads, and the first recording The head support member blocks an area in the transport direction between the first print head row and the second print head row, and the second print head support member serves as the second print head. A region in the transport direction between the row and the third printhead row is sealed, and the plurality of second printheads eject ink of a first color, and the plurality of third printheads Ejects ink of a second color different from the first color Inkjet recording apparatus.

According to this, it is possible to prevent the ink mist due to the ejected ink from floating in the opposite ejection direction during image recording. That is, it is possible to prevent the ink mist from floating in the anti-ejection direction in a region separated in the transport direction. A properly sealed state can be secured. The effect can be exhibited particularly when the gap exceeds 5 mm and a large amount of ink mist is generated. The recording head includes at least an element for ejecting ink.

This ink jet recording apparatus can also be configured as follows. That is, the plurality of fasteners are not projected from the respective recording heads toward the conveyance surface of the conveyance unit in a state where the plurality of recording heads are fastened to the recording head support member. it may be as we provided in the recording unit. According to this, the state sealed suitably can be ensured.

  According to the present invention, an ink jet recording apparatus capable of reducing contamination by ink mist can be obtained.

It is a figure which shows the outline of a line type inkjet recording device. (A) is a top view, (b) is a front view. FIG. 3 is a diagram illustrating an outline of a recording unit viewed from the ink ejection surface side. It is a schematic end view of the AA line shown in FIG. It is a schematic end view of the BB line shown in FIG. It is a figure which shows the gap dependence of an ink mist, Comprising: (a) is a table | surface which shows the relationship between a gap and the amount of ink mist generation | occurrence | production, (b) is the graph which graphed (a).

  Embodiments for carrying out the present invention will be described with reference to the drawings. The present invention is not limited to the configurations described below, and various configurations can be employed in the same technical idea. For example, some of the configurations shown below may be omitted or replaced with other configurations. Moreover, you may make it include another structure.

(Inkjet recording device)
As shown in FIG. 1, the inkjet recording apparatus 1 includes a conveyance unit 10, a carriage 20, a recording unit 30, an ultraviolet irradiation unit 40, and a control unit 50. The ink jet recording apparatus includes a serial type ink jet recording apparatus and a line type ink jet recording apparatus. In this embodiment, the case where the inkjet recording apparatus 1 is a line type inkjet recording apparatus will be described as an example. In the inkjet recording apparatus 1, a full-color image is formed on the recording surface 72 of the industrial material 70 as a recording medium. The industrial material 70 as a recording medium includes a building exterior material such as a ceramic siding material in addition to a concrete block as shown in FIG. An active energy curable ink is used for image recording in the ink jet recording apparatus 1. Examples of the active energy curable ink include ultraviolet curable ink and electron beam curable ink. In this embodiment, an ultraviolet curable ink will be described as an example.

  The conveyance unit 10 is configured by a conveyor or the like. The transport unit 10 transports the industrial material 70 placed on the transport surface 12. The transport unit 10 allows the industrial material 70 to pass through the carriage 20 and the ultraviolet irradiation unit 40 from one end side of the transport unit 10 (the left end side when FIG. 1A and FIG. 1B are viewed from the front). (Refer to the two-dot chain line industrial material 70 shown on the right side when FIGS. 1A and 1B are viewed from the front).

  The carriage 20 includes a recording unit 30. The recording unit 30 is attached and fixed to the carriage 20. The recording unit 30 includes recording head units 32K, 32C, 32M, and 32Y as shown in FIG. The recording head unit 32K includes a plurality of recording heads that discharge black ultraviolet curable ink (hereinafter also referred to as “ultraviolet curable black ink”). In the example shown in FIG. 2, the recording head 34 includes six recording heads 34K1 to 34K6. The recording head unit 32 </ b> C includes a plurality of recording heads that discharge cyan ultraviolet curable ink (hereinafter also referred to as “ultraviolet curable cyan ink”). In the example illustrated in FIG. 2, the recording head 34 includes six recording heads 34 </ b> C <b> 1 to 34 </ b> C <b> 6. The recording head unit 32M includes a plurality of recording heads that eject magenta ultraviolet curable ink (hereinafter also referred to as “ultraviolet curable magenta ink”). In the example shown in FIG. 2, the recording head 34 includes six recording heads 34M1 to 34M6. The recording head unit 32Y includes a plurality of recording heads that discharge yellow ultraviolet curable ink (hereinafter also referred to as “ultraviolet curable yellow ink”). In the example illustrated in FIG. 2, the recording head 34 includes six recording heads 34Y1 to 34Y6.

  A gap G (see FIG. 1B) between the recording unit 30 (in detail, an ink ejection surface 348 described later) and the recording surface 72 of the industrial material 70 is about 5 mm to 10 mm or about several tens of mm away. It is set to the state. In a state where the recording unit 30 is attached to the carriage 20, the surface of the carriage 20 facing the conveyance surface 12 and the ink ejection surface 348 of the recording unit 30 are set to the same height so as to be included in the same plane. Is done. The recording unit 30 will be described later.

  The ultraviolet irradiation unit 40 functions as an active energy irradiation unit that irradiates active energy. The ultraviolet irradiation unit 40 is installed at a predetermined position downstream of the recording unit 30 in the transport direction. The ultraviolet irradiation unit 40 includes an ultraviolet lamp installed toward the conveyance surface 12 of the conveyance unit 10 and irradiates ultraviolet rays as active energy rays in the direction of the conveyance surface 12. The ultraviolet irradiation unit 40 includes a shutter mechanism that can prevent the ultraviolet rays emitted from the ultraviolet lamp from being radiated to the outside. By opening and closing the shutter mechanism, the ultraviolet irradiation can be started and stopped. The start and stop of ultraviolet irradiation may be realized by turning on and off an ultraviolet lamp provided in the ultraviolet irradiation unit 40. In this case, the shutter mechanism can be omitted.

  The irradiation of ultraviolet rays is performed by, for example, a detection sensor (not shown) installed at a predetermined position downstream of the recording unit 30 in the conveyance direction and upstream of the ultraviolet irradiation unit 40 in the conveyance direction. It is started on the condition that passage is detected. The ultraviolet irradiation is performed by detecting that the industrial material 70 has passed through the ultraviolet irradiation unit 40 by a detection sensor (not shown) installed at a predetermined position downstream of the ultraviolet irradiation unit 40 in the transport direction. Stopped as a condition. You may make it stop irradiation of an ultraviolet-ray when predetermined time passes after the start of irradiation of an ultraviolet-ray.

  The control unit 50 controls various processes including image recording performed by the inkjet recording apparatus 1. The control unit 50 includes a circuit board on which electronic components are mounted, electrical wiring, and the like. At least a part of the configuration included in the control unit 50 is installed in the upper part of the recording unit 30.

  In addition, the inkjet recording apparatus 1 includes a main tank (not shown) that stores, for example, black, cyan, magenta, and yellow ultraviolet curable inks. The ultraviolet curable black ink stored in the black main tank is supplied to the recording heads 34K1 to 34K6 of the recording head unit 32K via the black ink supply line 60. The ultraviolet curable cyan ink stored in the cyan main tank is supplied to the recording heads 34C1 to 34C6 of the recording head unit 32C via the cyan ink supply line 60. The ultraviolet curable magenta ink stored in the magenta main tank is supplied to the recording heads 34M1 to 34M6 of the recording head unit 32M via the magenta ink supply line 60. The ultraviolet curable yellow ink stored in the yellow main tank is supplied to the recording heads 34Y1 to 34Y6 of the recording head unit 32Y via the yellow ink supply line 60. In FIGS. 1A and 1B, the ink supply lines 60 for the respective colors are shown in a simplified manner.

  Further, the inkjet recording apparatus 1 includes a predetermined interface (not shown) such as a network interface. The ink jet recording apparatus 1 is connected to an external device such as a personal computer via an interface so as to be communicable. The external device inputs an image recording command to the recording surface 72 and data indicating the image to be recorded to the inkjet recording apparatus 1. In the inkjet recording apparatus 1 to which the recording command is input, the following processing is executed, and an image indicated by the input data is recorded on the industrial material 70.

  First, the transport unit 10 starts operating, and transport of the industrial material 70 placed on the transport surface 12 is started. Next, in the recording unit 30, black dots made of ultraviolet curable black ink, cyan ink dots made of ultraviolet curable cyan ink, magenta dots made of ultraviolet curable magenta ink, and yellow dots made of ultraviolet curable yellow ink are: Recorded on the recording surface 72. In the recording, the ink jet recording apparatus 1 generates ink mist due to the discharged ultraviolet curable ink. Since the industrial material 70 has large irregularities on the recording surface 72, it is necessary to widen the gap G with the recording surface 72 in the inkjet recording apparatus for industrial materials. When the gap G is widened, the ink droplets are split and partly become mist before landing on the recording surface 72. When the gap G between the ink discharge surface 348 and the recording surface 72 becomes wide, ink mist is likely to occur. In addition, even when recording the entire recording surface 72 of the industrial material 70, the recording range is set somewhat wide in consideration of the recording positional deviation, so that ink droplets ejected outside the recording surface 72 during the recording soar. Ink mist is likely to occur.

  Thereafter, the industrial material 70 is further transported by the transport unit 10, and the recording surface 72 is irradiated with ultraviolet rays in the ultraviolet irradiation unit 40. In other words, ultraviolet rays are applied to ink droplets of ultraviolet curable ink of each color that land on the recording surface 72 and form black dots, cyan dots, magenta dots, and yellow dots. As a result, black dots, cyan dots, magenta dots, and yellow dots are cured, and image recording for one industrial material 70 is completed. In addition, the industrial material 70 can be sequentially placed on the transport surface 12 at a predetermined timing, the transport thereof can be started, and the above processing can be repeated continuously. In this case, the ink mist is accumulated and the total amount generated is increased. Since the recording surface 72 of the industrial material 70 is uneven, a turbulent flow is generated when the industrial material 70 is conveyed, and the generated ink mist is likely to be scattered.

(Recording part)
As shown in FIG. 2, the recording head units 32K, 32C, 32M, and 32Y in the recording unit 30 are arranged from the upstream side to the downstream side in the transport direction from the recording head unit 32K, the recording head unit 32C, the recording head unit 32M, and the recording head unit. The head units 32Y are arranged in this order. The arrangement order of the recording head units 32K, 32C, 32M, and 32Y is not limited to this, and may be appropriately changed in consideration of various conditions.

  As shown in FIG. 2, the recording head unit 32K is configured by two recording head rows arranged in the transport direction. Each recording head row constituting the recording head unit 32K is configured by recording heads 34K1 to 34K3 and recording heads 34K4 to 34K6 aligned in a direction orthogonal to the transport direction on a horizontal plane (see “orthogonal direction” in FIG. 2). . In the recording head unit 32K, the recording head rows of the three / row recording heads 34K1 to 34K6 arranged in the orthogonal direction are displaced in the orthogonal direction due to the positional relationship in which the six recording heads 34K1 to 34K6 are arranged in a staggered manner. Are arranged.

  For example, as shown in FIG. 3, the recording head 34 </ b> K <b> 1 includes a head main body 342 and a sub tank 344. The head main body 342 of the recording head 34K1 includes a plurality of ejection openings 346 that eject ultraviolet curable black ink. The plurality of discharge ports 346 are arranged in a staggered manner. The head main body 342 includes an ink ejection surface 348. The ink ejection surface 348 is a surface on which a plurality of ejection ports 346 are formed, and is a surface facing the recording surface 72 of the industrial material 70 placed on the transport surface 12. The sub tank 344 of the recording head 34K1 temporarily stores ultraviolet curable black ink supplied from a main tank (not shown) via the black ink supply line 60. The stored ultraviolet curable black ink is supplied to the head main body 342 through a predetermined flow path (not shown) connecting the sub tank 344 and the head main body 342 and discharged from the discharge port 346.

  Of the side surfaces of the recording head 34K1, two upper portions of the side surfaces that intersect with the conveyance direction, specifically, perpendicular to each other, have a flange 350 so as to protrude in the conveyance direction and the opposite direction, for example, as shown in FIG. Is formed. A through hole 352 that penetrates in a direction that coincides with the discharge direction of the ultraviolet curable ink is provided at a predetermined position of the collar portion 350. In FIG. 3, the discharge port 346 is not shown. Functions of the flange portion 350 and the through hole 352 will be described later. The recording heads 34K1 to 34K6 have the same configuration. A description of the recording heads 34K2 to 34K6 is omitted.

  As shown in FIG. 2, the recording head unit 32 </ b> C includes two recording head rows arranged in the transport direction. Each recording head row constituting the recording head unit 32C is configured by recording heads 34C1 to 34C3 and recording heads 34C4 to 34C6 aligned in a direction perpendicular to the transport direction on a horizontal plane. In the recording head unit 32C, the recording head rows of the three recording heads 34C1 to 34C6 arranged in the orthogonal direction are shifted in the orthogonal direction due to the positional relationship in which the six recording heads 34C1 to 34C6 are arranged in a staggered manner. Are arranged. The recording heads 34C1 to 34C6 differ from the recording head 34K1 in the ink color of the target ultraviolet curable ink, but are the same as the recording head 34K1 described above in other respects. That is, the head main body 342 included in each of the recording heads 34C1 to 34C6 includes a plurality of ejection ports 346 that eject ultraviolet curable cyan ink. The sub tank 344 provided in each of the recording heads 34C1 to 34C6 temporarily stores ultraviolet curable cyan ink supplied from a main tank (not shown) via the cyan ink supply line 60. Description of the recording heads 34C1 to 34C6 is omitted.

  As shown in FIG. 2, the recording head unit 32M includes two recording head rows arranged in the transport direction. Each recording head row constituting the recording head unit 32M is configured by recording heads 34M1 to 34M3 and recording heads 34M4 to 34M6 aligned in a direction perpendicular to the transport direction on a horizontal plane. In the recording head unit 32M, the recording head rows of the three / row recording heads 34M1 to 34M6 arranged in the orthogonal direction are displaced in the orthogonal direction due to the positional relationship in which the six recording heads 34M1 to 34M6 are arranged in a staggered manner. Are arranged. The recording heads 34M1 to 34M6 differ from the recording head 34K1 in the ink color of the target ultraviolet curable ink, but are the same as the recording head 34K1 described above in other respects. That is, the head main body 342 included in each of the recording heads 34M1 to 34M6 includes a plurality of ejection ports 346 that eject ultraviolet curable magenta ink. In addition, the UV curable magenta ink supplied from the main tank (not shown) via the magenta ink supply line 60 is temporarily stored in the sub tank 344 provided in each of the recording heads 34M1 to 34M6. A description of the recording heads 34M1 to 34M6 is omitted.

  As shown in FIG. 2, the recording head unit 32Y includes two recording head rows arranged in the transport direction. Each recording head row constituting the recording head unit 32Y is configured by recording heads 34Y1 to 34Y3 and recording heads 34Y4 to 34Y6 aligned in a direction perpendicular to the transport direction on a horizontal plane. In the recording head unit 32Y, the recording head rows of the three / row recording heads 34Y1 to 34Y6 arranged in the orthogonal direction are shifted in the orthogonal direction due to the positional relationship in which the six recording heads 34Y1 to 34Y6 are arranged in a staggered manner. Are arranged. The recording heads 34Y1 to 34Y6 differ from the recording head 34K1 in the ink color of the target ultraviolet curable ink, but are the same as the recording head 34K1 described above in other respects. That is, the head main body 342 included in each of the recording heads 34Y1 to 34Y6 includes a plurality of ejection ports 346 that eject ultraviolet curable yellow ink. The sub tank 344 included in each of the recording heads 34Y1 to 34Y6 temporarily stores ultraviolet curable yellow ink supplied from a main tank (not shown) via the yellow ink supply line 60. Description of the recording heads 34Y1 to 34Y6 is omitted.

  The recording unit 30 may include a recording head unit having an ink color different from black, cyan, magenta, and yellow. The number of recording head columns constituting each of the recording head units 32K, 32C, 32M, and 32Y is not limited to the above, and may be appropriately changed in consideration of various conditions. The same applies to the number of recording heads constituting one recording head row. In the following, the recording head array formed by the recording heads 34K1 to 34K3 is referred to as a first recording head array, and the recording heads 34K4 to 34K6 are referred to as second recording head arrays. A recording head array formed by the recording heads 34C1 to 34C3 is referred to as a third recording head array, and the recording heads 34C4 to 34C6 are referred to as a fourth recording head array. A recording head array formed by the recording heads 34M1 to 34M3 is referred to as a fifth recording head array, and the recording heads 34M4 to 34M6 are referred to as a sixth recording head array. A recording head array formed by the recording heads 34Y1 to 34Y3 is referred to as a seventh recording head array, and the recording heads 34Y4 to 34Y6 are referred to as an eighth recording head array.

  Here, in the recording unit 30, the first recording head row and the second recording head row cross the transport direction, specifically, the side surfaces orthogonal to each other (hereinafter, described as an example of “orthogonal”) are transported. They are parallel and spaced apart in the direction. The same applies to the third and fourth recording head arrays, the fifth and sixth recording head arrays, and the seventh and eighth recording head arrays. In this regard, the positional relationship between the first recording head array and the second recording head array will be described by taking the recording head 34K1 of the first recording head array and the recording head 34K4 of the second recording head array as an example. Of the surfaces forming the outer surface of the recording head 34K1, a part of the side surface that is orthogonal to the conveying direction and downstream in the conveying direction and the surface that forms the outer surface of the recording head 34K4 is orthogonal to the conveying direction and conveying direction. As shown in FIGS. 2 and 3, a part of the side surface on the upstream side is parallel (opposed) in a state of being separated by a width W1 in the transport direction.

  Further, the second recording head array and the third recording head array, the fourth recording head array and the fifth recording head array, and the sixth recording head array and the seventh recording head array, which have different ink colors, are also described above. Similarly, the positions are parallel and spaced apart. In this regard, the positional relationship between the second recording head array and the third recording head array will be described by taking the recording head 34K4 of the second recording head array and the recording head 34C1 of the third recording head array as an example. Among the surfaces forming the outer surface of the recording head 34K4, a part of the side surface that is orthogonal to the conveyance direction and downstream of the conveyance direction and the surface that forms the outer surface of the recording head 34C1 are orthogonal to the conveyance direction and are in the conveyance direction. As shown in FIGS. 2 and 3, a part of the side surface on the upstream side is parallel (opposed) in a state of being separated by a width W2 in the transport direction. That is, in each of these recording head arrays arranged in the transport direction, the side surfaces perpendicular to the transport direction are separated from each other in the transport direction. Note that the width W1 and the width W2 are equal or have a relationship in which either one is larger (smaller) than the other.

  In the recording unit 30, the recording head arrays are connected via recording head support members 36 disposed between adjacent recording head arrays. The adjacent recording head rows are connected via the recording head support member 36 by, for example, screwing as shown in FIG. As apparent from FIGS. 2 and 3, the recording head support member 36 is a plate-like member, and a female screw portion 362 into which a bolt 37 for connection is screwed is formed at a predetermined position. As shown in FIG. 2, the recording head support member 36 has substantially the same length as the dimensions of the recording head units 32K, 32C, 32M, and 32Y in the orthogonal direction. The recording head support member 36 has a predetermined thickness t as shown in FIG. In addition, the first and second recording head rows, the third and fourth recording head rows, the fifth and sixth recording head rows, the seventh and eighth recording head rows, The recording head support members 36 to be coupled have substantially the same width that is slightly narrower than the width W1, for example. The recording head support member 36 that connects the second recording head array, the third recording head array, the fourth recording head array, the fifth recording head array, the sixth recording head array, and the seventh recording head array is slightly smaller than, for example, the width W2. Have substantially the same width. The recording head support member 36 is not formed with a hole that penetrates the thickness direction in addition to the female screw portion 362. The female screw portion 362 is also partway along the recording head support member 36 and does not have to penetrate the recording head support member 36.

  The state in which the adjacent recording head arrays are connected to each other is indicated by the recording head 34K1 of the first recording head array and the recording head 34K4 of the second recording head array, and the recording head 34K4 of the second recording head array and the third recording head array. The recording head 34C1 will be described as an example with reference to FIG.

  First, in a state where the recording head 34K1 and the recording head 34K4 are connected, the recording head 34K1 and the recording head 34K4 are separated by a width W1, and the side surfaces orthogonal to the conveyance direction of the recording heads 34K1 and 34K4 are parallel to each other ( Opposite). The recording head support member 36 is disposed in a space having a width W1 extending in the orthogonal direction. The recording head support member 36 is in surface contact with the flange portion 350 that protrudes in the conveyance direction of the recording head 34K1 and the flange portion 350 that protrudes in the direction opposite to the conveyance direction of the recording head 34K4. The through hole 352 of each flange 350 and the female screw 362 of the recording head support member 36 are in communication with each other. Bolts 37 are inserted into the respective through holes 352 from above the recording heads 34K1 and 34K4, and the bolts 37 are screwed into the respective female screw portions 362. In a state where the recording head 34K1 and the recording head 34K4 are connected, the space between the recording heads extending in the orthogonal direction including the space of the width W1 is sealed over the entire region in the orthogonal direction.

  Next, in a state where the recording head 34K4 and the recording head 34C1 are connected, the recording head 34K4 and the recording head 34C1 are separated from each other by a width W2, and the side surfaces orthogonal to the conveyance directions of the recording heads 34K4 and 34C1 are parallel to each other. (Facing). The recording head support member 36 is disposed in a space having a width W2 extending in the orthogonal direction. The recording head support member 36 is in surface contact with the flange portion 350 that protrudes in the conveyance direction of the recording head 34K4 and the flange portion 350 that protrudes in the direction opposite to the conveyance direction of the recording head 34C1. The through hole 352 of each flange 350 and the female screw 362 of the recording head support member 36 are in communication with each other. Bolts 37 are inserted into the respective through holes 352 from above the recording heads 34K4 and 34C1, and the bolts 37 are screwed into the respective female screw portions 362. In a state where the recording head 34K4 and the recording head 34C1 are connected, the space between the recording heads extending in the orthogonal direction including the space of the width W2 is sealed over the entire region in the orthogonal direction.

  The ink jet recording apparatus 1 realizes the connection structure via the recording head support member 36 as described above in the entire recording unit 30. Therefore, according to the inkjet recording apparatus 1, the space between the recording heads can be totally sealed. Therefore, in the ink jet recording apparatus 1, the ink mist generated by the ultraviolet curable ink ejected during recording floats and passes through the space between the recording heads in the anti-ejection direction, and is above the recording unit 30, for example, the control unit 50. Occurrence of a state of adhering to various components and / or the ink supply line 60 can be suitably prevented. The number of maintenances of the ink jet recording apparatus 1 can be reduced, and the life of the ink jet recording apparatus 1 can be improved. Since the bolt 37 is screwed into the female screw portion 362, the ink mist does not pass through the female screw portion 362.

  Further, the recording heads 34K1 to 34K3, 34K4 to 34K6, etc. constituting each recording head row in the recording unit 30 have a positional relationship in which side surfaces parallel to the transport direction are close to each other as shown in FIG. The width W3 between the side surfaces is set to about 1 mm to 2.5 mm, for example, 1.3 mm. In this regard, the recording heads 34K1 to 34K3 constituting the first recording head row will be described as an example. As shown in FIG. 4, the recording head 34 </ b> K <b> 1 and the recording head 34 </ b> K <b> 2 are in a state in which the opposing side surfaces of the recording heads 34 </ b> K <b> 1 and 34 </ b> K <b> 2 are parallel to each other. Further, as shown in FIG. 4, the recording head 34K2 and the recording head 34K3 are in a state in which the opposing side surfaces of the recording heads 34K2 and 34K3 parallel to the transport direction are close to each other. The side surfaces parallel to the conveyance direction of the recording heads 34K1 to 34K3 can also be brought into close contact with each other.

  As described above, the ink jet recording apparatus 1 includes the recording unit 30 in which the opposing side surfaces parallel to the transport direction in each recording head row approach or are in close contact with each other. Therefore, according to the ink jet recording apparatus 1, the space formed by the opposing side surfaces parallel to the transport direction can be substantially blocked or sealed as a whole. Therefore, in the ink jet recording apparatus 1, the ink mist of the ultraviolet curable ink ejected at the time of recording floats and passes through this space in the opposite ejection direction, and is above the recording unit 30, for example, various components of the control unit 50. And / or occurrence of a state of adhering to the ink supply line 60 can be suitably prevented. The number of maintenance operations of the ink jet recording apparatus 1 can be reduced, and the life of the ink jet recording apparatus 1 can be extended.

  As described above, when the recording medium is the industrial material 70, the gap G is set at a distance of about 5 mm to 10 mm, for example. The inventor examined the gap dependency of ink mist and found the relationship shown in FIGS. 5 (a) and 5 (b). Note that the amount of ink mist generated in FIGS. 5A and 5B is obtained based on the weight of the ink droplets landed on the recording medium when the gap G is 0.5 mm. Specifically, the ink mist generation amount was obtained by calculating the difference between the reference weight and the weight of the ink droplet landed in each gap G shown in FIG. 5A and dividing the difference by the reference weight. Values are expressed as percentages. According to FIGS. 5A and 5B, ink mist is hardly generated in a region where the gap G is narrow. However, when the gap G widens, for example, exceeding 5 mm, the order of the ink mist generation amount increases by an order of magnitude, and the amount of ink mist generation increases. For example, the ink mist generation amount when the gap G is 9 mm is 2.6%. When ink droplets that land when the gap G is 0.5 mm are used as a reference, it can be seen that 2.6% by weight of ink droplets are ink mist. As is clear from the relationship shown in FIGS. 5A and 5B, the configuration of this embodiment must have a wide gap G as in the industrial material 70. As a result, a large amount of ink mist is generated. In particular, the effect can be exerted in the case where it occurs.

  The configuration of the present embodiment described above can also be as follows. That is, in the example shown in FIG. 3, in the state where the recording head support member 36 is connected, a space of width W1 or width W2 remains between the connected recording heads (between the recording head arrays). Yes. The thickness t of the recording head support member 36 may be increased so that the spaces with the widths W1 and W2 do not remain. In this case, in a state where the recording head support member 36 is fastened with the bolt 37, the recording head is arranged such that the back surface of the surface of the recording head support member 36 that is in surface contact with the flange 350 is flush with the ink ejection surface 348. The thickness t of the support member 36 may be set. The surface of the recording unit 30 facing the recording surface 72 is a flat surface, and the ink ejection surface 348 can be suitably wiped, that is, cleaned. In the state in which such a recording head support member 36 is employed, each recording head (each recording head row), specifically, the side surfaces orthogonal to the transport direction are in a state in which the recording head support member 36 is interposed. Then, they are spaced apart in parallel.

In the above description, the recording head arrays are connected via the recording head support member 36, and the space between the recording heads is sealed by the recording head support member 36. That is, in the above, the recording head support member 36 functions as a means for sealing the space between the recording heads. By the way, such blocking may be performed by filling the space between the recording heads with a resin or the like. As shown in FIG. 3, the resin is filled so that a part of the space having the widths W1 and W2 remains, or the entire space having the widths W1 and W2 is filled. Furthermore, based on between the ink colors are different each recording head row (Fig. 2, second, between the third recording head column, fourth, between the fifth recording head column, sixth, seventh recording head array The recording head rows adjacent in the transport direction may be approached or brought into close contact with each other. In these cases, the recording head support member 36 and the like can be omitted. The recording heads 34K1 to 34K6, 34C1 to 34C6, 34M1 to 34M6, 34Y1 to 34Y6 are fixed to the carriage 20, respectively. In addition, between the side surfaces parallel to the conveyance direction shown in FIG. 4 may be filled with resin or the like, and the space between them may be sealed.

  In the above description, for example, as shown in FIGS. 3 and 4, the recording head 34 </ b> K <b> 1 in which the head main body 342 and the sub tank 344 are integrated has been described as an example. In addition, the head main body 342 and the sub tank 344 may be separated from each other, and both may be piped by a tube or the like. In this case, a flange portion 350 and the like are formed on the two side surface upper portions of the side surface of the head main body 342 that intersect (orthogonal) the conveyance direction so as to protrude in the conveyance direction and the opposite direction. The recording heads 34K1 to 34K6, 34C1 to 34C6, 34M1 to 34M6, and 34Y1 to 34Y6 configured by the head main body 342 realize the same configuration as described above.

  In the above, as shown in FIG. 2, the recording heads 34K1 to 34K6, the recording heads 34C1 to 34C6, the recording heads 34M1 to 34M6, and the recording heads 34Y1 to 34Y6 are displaced in the orthogonal direction due to the positional relationship in which they are arranged in a staggered manner. The configuration arranged as described above has been described as an example. In such a case, a predetermined space is formed on one side of the first to eighth recording head arrays in the orthogonal direction. Specifically, in the first recording head row, this predetermined space is formed on the side surface of the both sides of the recording head 34K3 parallel to the transport direction that does not face the recording head 34K2 (in FIG. 2, cutting is performed). (Refer to a portion where a dashed-dotted arrow “B” indicating a portion is shown). Further, in the second recording head row, this predetermined space is formed on the side of the recording head 34K4 parallel to the transport direction on the side surface that does not face the recording head 34K5 (in FIG. 2, reference numeral 34K4). (Refer to the portion where the leader line is shown). Although not described here, the same applies to the third to eighth recording head arrays.

  In the ink jet recording apparatus 1, such a predetermined space may be sealed. Specifically, for example, a plate-like or block-like member (blocking member) may be arranged in this predetermined space. This plate-like or block-like member is fixed to the recording head support member 36 by a method such as screwing. For the predetermined spaces in the recording heads 34K4, 34C3, 34C4, 34M3, 34M4, and 34Y3, the plate-like or block-like member crosses the adjacent recording head support member 36 via these predetermined spaces. Arranged and fixed to the respective recording head support members 36. In this case, the plate-like or block-like member may be fixed so as to be fitted between the recording head support members 36. According to such a configuration, a more suitable blockage can be realized. That is, the state where the ink mist floats in the predetermined ejection space in the anti-ejection direction and adheres to the various parts of the control unit 50 and / or the ink supply line 60 above the recording unit 30, for example. Can be more preferably prevented.

DESCRIPTION OF SYMBOLS 1 Inkjet recording device 10 Conveyance part, 12 Conveyance surface 30 Recording part 32K Recording head unit (for black)
32C recording head unit (for cyan)
32M recording head unit (for magenta)
32Y recording head unit (for yellow)
34K1-34K6 recording head (for black)
34C1-34C6 print head (for cyan)
34M1-34M6 print head (for magenta)
34Y1-34Y6 print head (for yellow)
342 Head main body, 344 Sub tank, 348 Ink discharge surface 350 鍔 part 36 Recording head support member 70 Industrial material, 72 Recording surface

Claims (2)

An inkjet recording apparatus that conveys a recording medium, ejects ink onto the recording medium, and records an image,
A transport unit for transporting the recording medium;
In order to record the image, each of a plurality of recording heads that eject ink onto the recording medium conveyed by the conveyance unit, a recording head support member that connects the plurality of recording heads, and each of the plurality of recording heads A recording unit comprising a plurality of fasteners for fastening the recording head to the recording head support member;
Recording of the recording medium separated from the recording head support member and fixed by the plurality of recording heads connected by the recording head support member and transported by the recording unit and the transport unit A carriage installed above the transport surface of the transport unit in a state where the gap with the surface is 5 mm or more;
A control part included in the control unit of the ink jet recording apparatus and installed on the upper part of the recording unit fixed to the carriage ;
The recording head support member is
A first recording head row by a plurality of first recording heads of the plurality of recording heads arranged in a perpendicular direction orthogonal to the transport direction at a first position in the transport direction of the recording medium by the transport unit; Of the plurality of recording heads, the first recording head row is spaced apart in parallel in the transport direction and arranged in the orthogonal direction at a second position downstream of the transport direction from the first position in the transport direction. A first recording head support member for connecting a plurality of first recording heads and a second recording head array formed by a plurality of second recording heads, which are separate bodies;
The second recording head row, the second recording head row and the second recording head row are spaced apart from each other in the transport direction, and are arranged in the orthogonal direction at a third position downstream from the second position in the transport direction. Of the plurality of recording heads arranged side by side, the plurality of first recording heads and the plurality of second recording heads are connected to a third recording head array formed by a plurality of third recording heads that are separate bodies. A second recording head support member,
The first recording head support member seals a region in the transport direction between the first recording head row and the second recording head row,
The second recording head support member seals a region in the transport direction between the second recording head row and the third recording head row;
The plurality of second recording heads eject ink of a first color;
Wherein the plurality of the third recording head is an ink jet recording apparatus that discharges ink of the second color different from said first color. The plurality of fasteners may be configured such that each of the plurality of recording heads is fastened to the recording head support member, and does not protrude from the respective recording heads toward the conveying surface of the conveying unit. An ink jet recording apparatus according to claim 1 is provided et al.

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