JP2009285840A - Inkjet head, head unit and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily cool a driving circuit which controls a driving part for ejecting an ink from outlets while making an inkjet head compact in size in a printer of an inkjet system. <P>SOLUTION: At each inkjet head of the printer, a common collecting passage 344 and a circuit cooling passage 345 to which the ink drawn out of a first print head and a second print head flows in are formed at an intermediate supporting member 34 where the first print head and the second print head are attached to both sides in a scan direction. The inkjet head can thus be simplified in structure and made compact in size. The ink flowing in from a first head end passage and a second head end passage is made to pass the vicinity of a first driving circuit and a second driving circuit substantially in contact with the intermediate supporting member 34 by the circuit cooling passage 345, whereby the first driving circuit and the second driving circuit can be cooled easily. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ink jet head that ejects ink droplets from a plurality of ejection openings toward a print medium in an ink jet printing apparatus, a head unit including the ink jet head, and printing including the head unit. Also related to the device.

  2. Description of the Related Art Conventionally, an ink jet printing apparatus that performs printing on a print medium by scanning a discharge mechanism in which a plurality of discharge ports for discharging minute ink droplets are arranged relative to the print medium has been used. ing.

  In the ink jet printing apparatus disclosed in Patent Document 1, in a line head that ejects micro droplets of ink, a plurality of head modules each having two heads arranged in the scanning direction of the printing medium are arranged in a two-stage zigzag pattern. The plurality of head modules are attached to a common support substrate disposed between the two-stage head modules. By the way, in each head module of such an ink jet printing apparatus, when the ink introduction tube and the discharge tube to each head are connected to a surface perpendicular to the scanning direction of the head, the size of the head module in the scanning direction increases. End up. Therefore, in the line head disclosed in Patent Document 1, an ink flow path common to a plurality of head modules is provided inside the above-described common support substrate, and ink is supplied from the ink flow path to the two heads of each head module. Thus, the size of the line head in the scanning direction is reduced.

  On the other hand, Patent Document 2 discloses an ink circulation system in an ink jet printer pen that re-feeds ink collected from a print head to the print head while circulating the ink through an ink circulation path.

  Patent Document 3 proposes a structure for cooling a charge driver electronic device provided in an inkjet printer. In the inkjet printer of Patent Document 3, a printed circuit board is mounted on a frame for a print head independently from the print head, and a cooling plate is attached to a plurality of charge driver electronic devices arranged on one surface of the printed circuit board. The charge driver electronic device is cooled by the contact. In the ink jet printer of Patent Document 3, as the cooling fluid flowing inside the cooling plate, the ink before being supplied to the print head or the ink different from the ink supplied to the print head (that is, supplied to the print head) Not used).

Patent Document 4 relates to a printer head chip used in a printer head for a bubble ink jet printer. In the printer head chip, the ink is heated by a heating resistor provided in an ink pressurizing chamber corresponding to each ejection port. Ink pressure is generated in the ink pressurizing chamber to discharge ink droplets from the discharge ports. The printer head chip of Patent Document 4 has an ink channel groove that extends in the arrangement direction of the plurality of ejection ports and communicates with each ink pressurizing chamber, and circulates the ink in the ink channel groove to the outside of the printer head chip. By doing so, heat generated in the printer head chip is released to the outside.
JP 2007-90686 A Japanese Patent Laid-Open No. 7-251508 JP 2000-218828 A JP 2003-80711 A

  By the way, in an inkjet printing apparatus, normally, a plurality of ejection port arrays, each of which is a set of a plurality of ejection ports arranged in a predetermined arrangement direction, are arranged in a scanning direction substantially perpendicular to the arrangement direction. For this reason, if the size of the ejection mechanism in the scanning direction is large in a printing apparatus (so-called one-pass printing apparatus) that performs printing by a single scan of the ejection mechanism with respect to the printing medium, the meandering when the printing medium moves in the scanning direction Also, the displacement of the relative position of the discharge mechanism with respect to the base material due to feed unevenness or the like becomes large, and print quality may be deteriorated.

  Further, in a printing apparatus that performs printing by scanning the ejection mechanism a plurality of times on a print medium (so-called shuttle type printing apparatus), if the size of the ejection mechanism in the scanning direction is large, The moving distance becomes large and the productivity is lowered.

  Further, in a printing apparatus that uses ultraviolet curable ink, an ultraviolet lamp is usually provided behind the plurality of ejection openings (that is, the rear side in the scanning direction of the ejection mechanism), so that the size of the ejection mechanism in the scanning direction is large. If the thickness is large, the time from when the ink is ejected until it is irradiated with ultraviolet rays becomes long, and the print quality may be deteriorated due to ink bleeding.

  In the line head of Patent Document 1, since ink is supplied to each head module from the middle of a common ink flow path extending in the arrangement direction of a plurality of head modules, it is necessary to enlarge the ink flow path. There is a limit to miniaturization in the direction. In addition, since the pressure loss in each head module differs based on the pressure of the ink supplied to the line head, there is a difference in the ink flow rate and discharge amount between the head modules, which limits the improvement in print quality. There is. Furthermore, since the distance between each of the two heads and the ink flow path is different in each head module, the pressure loss is different between the two heads, which may cause a difference in the discharge amount.

  On the other hand, in the ink jet printer of Patent Document 3, it is necessary to provide a printed circuit board and a cooling plate that are independent of the print head, which increases the size of the head portion of the ink jet printer and complicates the structure. Further, in the structure of Patent Document 3, when a drive circuit or the like of a drive unit that discharges ink is provided in the print head, the drive circuit cannot be cooled.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problem, and an object of the present invention is to easily cool a drive circuit that controls a drive unit that ejects ink from an ejection port while downsizing an inkjet head in an inkjet printing apparatus. Yes.

  According to a first aspect of the present invention, there is provided an ink jet head that ejects micro droplets of ink from a plurality of ejection openings toward a print medium in an ink jet printing apparatus, wherein the plurality of first heads arranged in a predetermined arrangement direction. A second print head having a first print head having one discharge port and a plurality of second discharge ports arranged in the arrangement direction and arranged in a direction substantially perpendicular to the arrangement direction with respect to the first print head. A print head; and an intermediate support member disposed between the first print head and the second print head to which the first print head and the second print head are attached, the first print head comprising: A plurality of first ejection flow paths for guiding ink toward the plurality of first ejection openings; a direction for guiding the ink in parallel with the arrangement direction; and a contact with the plurality of first ejection flow paths. A plurality of first head end flow paths and a plurality of first discharge flow paths that are provided in the vicinity of the plurality of first discharge openings to discharge micro droplets of ink from the plurality of first discharge openings. A plurality of second ejection flows including a first driving unit and a first driving circuit for controlling the plurality of first driving units, wherein the second print head guides ink toward the plurality of second ejection ports. A plurality of second discharge ports of the plurality of second discharge flow paths, a second head end flow path connected to the plurality of second discharge flow paths while guiding the ink parallel to the arrangement direction. A plurality of second drive units provided in the vicinity for discharging micro droplets of ink from the plurality of second discharge ports; and a second drive circuit for controlling the plurality of second drive units. The drive circuit and the second drive circuit are substantially in contact with the intermediate support member; The support member passes the ink flowing in from the first head end channel and the second head end channel through the vicinity of the first drive circuit and the second drive circuit, and thereby the first drive circuit and A circuit cooling flow path for cooling the second drive circuit is provided.

  According to a second aspect of the present invention, in the ink jet head according to the first aspect, the intermediate support member causes the ink supplied from the outside to flow through the first head end channel and the second head end flow. A common supply flow path leading to the path is further provided.

  A third aspect of the present invention is the ink jet head according to the second aspect, wherein the intermediate support member is attached to the first print head in a direction in which the first print head and the second print head are arranged. An ink supply port provided at a position between a first mounting surface to be mounted and a second mounting surface to which the second print head is mounted, and into which the ink guided to the common supply flow path is introduced, and the first print head And an ink discharge port which is provided at a position between the first mounting surface and the second mounting surface in a direction in which the second print heads are arranged and discharges ink from the circuit cooling channel. .

  A fourth aspect of the present invention is the inkjet head according to any one of the first to third aspects, wherein the plurality of first discharge ports and the plurality of second discharge ports have the same pitch in the arrangement direction. In the arrangement direction, the plurality of first discharge ports are arranged at positions shifted by half of the pitch with respect to the plurality of second discharge ports.

  A fifth aspect of the present invention is the ink jet head according to any one of the first to fourth aspects, wherein each of the plurality of first drive units and each of the plurality of second drive units is a piezoelectric element. When each first driving unit is deformed, pressure is applied to the ink in the vicinity of the first ejection port corresponding to each first driving unit, and a minute droplet of ink is ejected from the first ejection port. When each second driving unit is deformed, pressure is applied to the ink in the vicinity of the second ejection port corresponding to each second driving unit, and micro droplets of ink are ejected from the second ejection port.

  A sixth aspect of the present invention is a head unit that ejects micro droplets of ink from a plurality of ejection openings toward a print medium in an ink jet printing apparatus, and the head unit according to any one of the first to fifth aspects. An inkjet head, another inkjet head having the same structure as the inkjet head, and at least partially overlapping the inkjet head in a direction in which the first print head and the second print head are arranged, the inkjet head, and An ink supply tank for storing ink to be supplied to the other ink jet head; and an ink recovery unit into which ink discharged from the ink jet head and the other ink jet head flows.

  The invention described in claim 7 is a head unit that discharges micro droplets of ink toward a printing medium from a plurality of discharge ports in an inkjet printing apparatus, and the inkjet head according to claim 3, Another inkjet head having the same structure as the inkjet head, and at least partially overlapping the inkjet head in a direction in which the first print head and the second print head are arranged, the inkjet head, and the other inkjet An ink supply tank for storing ink to be supplied to the head; and an ink collection unit for receiving ink discharged from the ink jet head and the other ink jet head, and the ink jet head and the other ink jet head. The ink supply port and the ink supply tank are linearly connected with the same flow path length and flow path diameter, and the ink discharge port of the ink jet head and the other ink jet head and the ink recovery section are the same flow path. It is connected in a straight line with a length and a channel diameter.

  The invention according to claim 8 is an ink jet type printing apparatus, wherein the head unit according to claim 6 or 7 and a circulation line for guiding ink from the ink recovery section of the head unit to the ink supply tank. And a scanning mechanism that moves the print medium relative to the head unit in a scanning direction that intersects the arrangement direction.

  The invention according to claim 9 is the printing apparatus according to claim 8, further comprising an ultraviolet irradiation unit that irradiates the ink on the print medium with ultraviolet rays, and the ink is ultraviolet curable ink.

  In the present invention, the first drive circuit and the second drive circuit can be easily cooled while downsizing the inkjet head. In the inventions of claims 2 and 3, the ink jet head can be further downsized.

  In the inventions of claims 6 and 7, the head unit can be reduced in size. Furthermore, in the invention of claim 7, the uniformity of pressure loss in a plurality of ink jet heads can be improved.

  FIG. 1 is a perspective view showing an appearance of a printing apparatus 1 according to an embodiment of the present invention. The printing apparatus 1 is an apparatus that performs color printing by an inkjet method on a substrate 9 that is a sheet-like printing medium having liquid repellency such as a film.

  The printing apparatus 1 illustrated in FIG. 1 includes a transport unit 27 that is a scanning mechanism that moves the sheet-like base material 9 in the Y direction (hereinafter, also referred to as “scan direction”) in FIG. A discharge mechanism 3 for discharging fine droplets of ink toward the substrate 9, and a control unit 4 for controlling the configuration thereof. In FIG. 1, for convenience of illustration, illustration of an ink circulation mechanism 5 described later is omitted.

  In the transport unit 27, a plurality of rollers 271 that are each long in the X direction in FIG. 1 are arranged in the Y direction, and a roll-shaped substrate 9 (supply roll) is placed on the (+ Y) side of the plurality of rollers 271. A supply unit 272 for holding is provided, and a winding unit 273 for holding the roll-shaped base material 9 (winding roll) is provided on the (−Y) side of the plurality of rollers 271. Actually, the base material 9 is rolled in each of the supply unit 272 and the winding unit 273. In the following description, the term “base material 9” simply means the base material 9 that is being conveyed (that is, the base material 9 on the plurality of rollers 271).

  An encoder 29 that detects the moving speed of the base material 9 in the scanning direction is provided on one roller 271 a of the transport unit 27, and a movement control unit 42 (see FIG. 11) described later is based on the output of the encoder 29. By controlling the rotation of the motor 273, the base material 9 moves at a constant speed in the (-Y) direction. At this time, by applying a load (tension) in the direction opposite to the movement direction (that is, (+ Y) direction) to the base material 9 by the motor of the supply unit 272, the base material on the plurality of rollers 271 is provided. 9 moves smoothly without undulations. Note that the encoder 29 that detects the moving speed of the base material 9 can be regarded as detecting a change in the position in the scanning direction of one part on the base material 9 during conveyance.

  The ejection mechanism 3 is disposed above the plurality of rollers 271, and the ejection mechanism 3 is fixed to the frame 25 provided on the base 20 so as to straddle the plurality of rollers 271. A light source 39 for emitting ultraviolet rays is provided on the frame 25, and a plurality of optical fibers (actually, the plurality of optical fibers are bundled. In FIG. The light from the light source 39 is introduced into the inside of the discharge mechanism 3.

  FIG. 2 is a bottom view showing the discharge mechanism 3. As shown in FIG. 2, the ejection mechanism 3 includes a plurality of (four in the present embodiment) ink jet head units 31 that eject inks of different colors, and these ink jet head units 31. Have a similar structure. The plurality of inkjet head units 31 are arranged in the Y direction (that is, the scanning direction) and attached to the head unit attachment portion 30 of the ejection mechanism 3. The most (+ Y) side inkjet head unit 31 in FIG. 2 ejects K (black) color ink, and the (−Y) side inkjet head unit 31 of the K inkjet head unit 31 is C (cyan). The color ink is ejected, the (−Y) side ink jet head unit 31 of the C ink jet head unit 31 ejects M (magenta) color ink, and the most (−Y) side ink jet head unit 31 is Y. (Yellow) color ink is ejected. Each color ink is an ultraviolet curable ink containing an ultraviolet curing agent.

  In the ejection mechanism 3, the lamp head unit 38, which is a head unit connected to the light source 39 (see FIG. 1), together with these inkjet head units 31 on the (−Y) side of the four inkjet head units 31. They are arranged in the Y direction (that is, the scanning direction) and attached to the head unit attachment portion 30. Here, when a plurality of head units attached to the head unit attachment portion 30 are collectively referred to as a head unit group, the head unit group includes the above-described inkjet head units 31 of K, C, M, and Y, and In addition to the lamp head unit 38, for example, an inkjet head unit for other colors such as light cyan, light magenta, and white may be included.

  In the lamp head unit 38, a plurality of optical fibers are arranged along the X direction, and linear irradiation extending in the X direction (that is, a direction perpendicular to the scanning direction) on the substrate 9 by the lamp head unit 38. The region is irradiated with ultraviolet light. In the printing apparatus 1, the ultraviolet curable ink ejected from the plurality of inkjet head units 31 onto the substrate 9 is irradiated with ultraviolet rays from the lamp head unit 38. Cured. In other words, the lamp head unit 38 is an ultraviolet irradiation unit that irradiates the ink discharged onto the substrate 9 with ultraviolet rays, and is also a curing head unit that cures the ink.

  In the printing apparatus 1, the inkjet head unit 31 and the lamp head unit 38 extend over the entire printing area on the base material 9 (here, the entire X direction of the base material 9 in the X direction perpendicular to the scanning direction). The printing of the image on the substrate 9 is completed only once the substrate 9 passes under the discharge mechanism 3 once (so-called one-pass printing is performed).

  FIGS. 3 and 4 are a bottom view and a front view, respectively, showing one inkjet head unit 31. As shown in FIG. 3, the inkjet head unit 31 includes a plurality (six in this embodiment) of inkjet heads 32, and these inkjet heads 32 have the same structure. Each inkjet head 32 has a plurality of discharge ports 331 arranged in two rows in a predetermined arrangement direction approximately parallel to the X direction in FIG. 3 on the lower surface (that is, the (−Z) side surface). Ink droplets are ejected from the plurality of ejection ports 331 toward the substrate 9. In FIG. 3, for convenience of illustration, the size of each discharge port 331 and the distance in the arrangement direction between adjacent discharge ports 331 are drawn larger than actual. Note that the actual inkjet head unit 31 is provided with a larger number of ejection ports 331 than shown in FIG.

  Moreover, the inkjet head unit 31 is further provided with the center rib 311 which is an attachment member to which the some inkjet head 32 is attached, as shown in FIG. 3 and FIG. The center rib 311 has a T-shaped outer shape when viewed along the X direction, a plate-shaped rib upper portion 3111 having a main surface substantially perpendicular to the Z direction, and a main rib substantially perpendicular to the Y direction. A plate-like rib lower portion 3112 having a surface is provided.

  As shown in FIG. 4, the ink jet head unit 31 is arranged above the plurality of ink jet heads 32 (that is, on the (+ Z) side) and the ink recovery unit 312 into which the ink discharged from the plurality of ink jet heads 32 flows. And an ink supply tank 313 that is disposed above the ink recovery unit 312 and that stores ink supplied to the plurality of inkjet heads 32. In FIG. 4, only the three inkjet heads 32 attached to the (+ Y) side of the rib lower portion 3112 of the center rib 311 among the six inkjet heads 32 of the inkjet head unit 31 are shown for easy understanding of the drawing. The three inkjet heads 32 attached to the (−Y) side of the rib lower part 3112 of the center rib 311 are not shown.

  As shown in FIG. 3, the plurality of inkjet heads 32 are arranged in the X direction so as to be alternately located on the (−Y) side and the (+ Y) side of the rib lower part 3112 of the center rib 311 (so-called staggered pattern). The inkjet heads 32 are arranged so that at least a portion thereof overlaps with the inkjet heads 32 adjacent in the X direction in the Y direction. For example, the inkjet head 32 positioned closest to the (−X) side on the (−Y) side of the rib lower portion 3112 is in the X direction with the inkjet head 32 positioned closest to the (−X) side of the (+ Y) side of the rib lower portion 3112. (In other words, the end of the former (+ X) side and the end of the latter (−X) side of the two inkjet heads 32 in the Y direction). overlapping.

  As shown in FIG. 4, the ink jet head unit 31 penetrates through the rib upper part 3111 of the center rib 311 to connect the ink supply tank 313 and the plurality of ink jet heads 32, and from the ink supply tank 313 to the plurality of ink jet heads 32. A plurality of ink introduction pipes 3131 for introducing ink to the head, and the ink recovery unit 312 and the plurality of inkjet heads 32 are connected to each other through the rib upper portion 3111 and the ink recovery units 312 are connected to the plurality of inkjet heads 32. A plurality of ink outlet pipes 3121 for leading ink to the head are provided.

  In the present embodiment, six linear ink introduction tubes 3131 and six linear ink outlet tubes 3121 are provided in the inkjet head unit 31, and the length of the six ink introduction tubes 3131 is provided. The inner diameter (that is, the channel length and the channel diameter by the six ink introduction pipes 3131) is made equal to each other. Further, the length and the inner diameter of the six ink outlet tubes 3121 (that is, the channel length and the channel diameter of the six ink outlet tubes 3121) are also made equal to each other. In other words, ink supply ports 3431 (see FIG. 9), which will be described later, of the six inkjet heads 32 and the ink supply tank 313 are linearly connected with the same channel length and channel diameter, and the six inkjet heads. An ink discharge port 3451 (see FIG. 9), which will be described later, of the head 32 and an ink recovery unit 312 are connected in a straight line with the same flow path length and flow path diameter.

  FIG. 5 is a view showing the ink circulation mechanism 5 connected to one inkjet head unit 31 and supplying the ink while circulating the ink to the inkjet head unit 31 together with the inkjet head unit 31. In the printing apparatus 1, one ink circulation mechanism 5 is connected to each of the plurality of inkjet head units 31 shown in FIG. As shown in FIG. 5, the ink circulation mechanism 5 includes a circulation line 51 that is used for supplying ink to the plurality of inkjet heads 32 of the inkjet head unit 31, and both ends of the circulation line 51 are arranged on the inkjet head unit 31. The ink supply tank 313 and the ink recovery unit 312 are connected. In the ink circulation mechanism 5, the ink that has flowed from the plurality of inkjet heads 32 to the ink recovery unit 312 is guided to the ink supply tank 313 by the circulation line 51, and is circulated to the plurality of inkjet heads 32 via the ink supply tank 313. And re-supply.

  On the circulation line 51, a flow rate adjustment valve 52 that is a flow rate adjustment unit, an external ink tank 53 that is an ink tank provided outside the inkjet head unit 31, a pump 54, and a filter 55 are provided. A pressure reducing mechanism 56 having a pump, a pressure adjusting valve, a pressure gauge, and the like is connected to the device. The external ink tank 53 is provided with a heater 531 that heats ink inside the external ink tank 53 as necessary.

In the ink circulation mechanism 5 hundreds millibars from within the external ink tank 53 (gas) is the atmospheric pressure by pressure reducing mechanism 56 (mbar) (e.g., 500 mbar. However, 1 bar is 10 ⁵ Pascals (Pa).) Only low Due to the pressure, a flow path from the ink supply tank 313 of the ink jet head unit 31 to the external ink tank 53 (that is, a part of the plurality of ink jet heads 32, the ink collection unit 312 and the circulation line 51 from the ink supply tank 313). Ink is sent from the ink supply tank 313 to the external ink tank 53 in a state where the path) to the external ink tank 53 via is filled with ink. Then, the ink in the external ink tank 53 is sent out by the pump 54, and unnecessary substances are removed by the filter 55, and then supplied to the ink supply tank 313 and stored.

  In this manner, the pump 54 is driven to supply the ink in the external ink tank 53 to the ink supply tank 313, and the ink is supplied from the ink supply tank 313 to the external ink tank 53 with a negative pressure in the external ink tank 53. By returning, the ink is appropriately circulated while degassing the ink in the external ink tank 53 using the negative pressure of the external ink tank 53. In the ink circulation mechanism 5, the flow rate adjustment valve 52 provided on the circulation line 51 between the ink recovery unit 312 and the external ink tank 53 allows flow according to the pressure difference between the ink supply tank 313 and the external ink tank 53. By adjusting the area of the path opening (that is, the opening of the flow path inside the flow rate adjusting valve 52), the ink flow rate from the ink supply tank 313 to the external ink tank 53 is adjusted to be substantially constant.

  In the inkjet head unit 31 shown in FIG. 4, as described above, a plurality of inkjet heads 32 are linearly connected to the ink supply tank 313 with the same flow path length and the same flow path diameter, and the same flow path length and the same. The ink collecting unit 312 is linearly connected with the flow path diameter. Thereby, in the plurality of inkjet heads 32, the pressure loss of the flow path from the ink supply tank 313 to the ink recovery unit 312 via the ink introduction pipe 3131, the inkjet head 32, and the ink outlet pipe 3121 becomes equal to each other. The plurality of ink jet heads 32 make the ink flow rate uniform.

  6 and 7. FIGS. 7A and 7B are a front view and a side view, respectively, showing an inkjet head 32 in an enlarged manner. B is an exploded side view showing the structure of the inkjet head 32 in an exploded manner. FIG. A and FIG. As shown in B, the inkjet head 32 has two print heads arranged in the Y direction (hereinafter, the (+ Y) side print head is referred to as a “first print head 33a”, and the (−Y) side print head is referred to as the “−Y” side print head. "Referred to as" second print head 33b "), and a plate-like intermediate portion disposed between the first print head 33a and the second print head 33b to which the first print head 33a and the second print head 33b are attached. A support member 34 is provided. The second print head 33b has substantially the same structure as the first print head 33a, and is opposite to the first print head 33a in the Y direction. In FIG. 6, only the first print head 33a and the intermediate support member 34 are depicted. FIG. In B, the first print head 33a, the intermediate support member 34, and the second print head 33b are drawn separately in the Y direction.

  FIG. FIG. 8A is a front view of the first print head 33a viewed from the (+ Y) side in the (−Y) direction, and FIG. B is a rear view showing the second print head 33b as viewed from the (+ Y) side in the (-Y) direction. 9 is a front view showing the intermediate support member 34, and FIG. A, FIG. B, FIG. C, FIG. D and FIG. E is a longitudinal sectional view obtained by cutting the inkjet head 32 at positions AA, BB, CC, DD and EE in FIG.

  The first print head 33a is shown in FIG. As shown in FIG. Ink is guided in the (−Z) direction toward the plurality of first ejection ports 331a and the plurality of first ejection ports 331a arranged at a predetermined pitch in a predetermined arrangement direction approximately parallel to the X direction in A. A plurality of first ejection channels 332a and a first head end channel 333a that guides ink parallel to the arrangement direction of the plurality of first ejection ports 331a and is connected to the plurality of first ejection channels 332a. . Note that FIG. In A, eight first discharge ports 331a and first discharge passages 332a are drawn, respectively, but the number of first discharge ports 331a and first discharge passages 332a actually provided in the first print head 33a is as follows. FIG. More than that shown in A (the same applies to the second print head 33b shown in FIG. 8.B).

  The first print head 33a is provided in the vicinity of the plurality of first discharge ports 331a of the plurality of first discharge channels 332a and discharges a plurality of ink droplets from the plurality of first discharge ports 331a. 1 drive part 334a (refer to Drawing 10C) and the 1st drive circuit 335a which controls a plurality of 1st drive parts 334a (namely, drive) are provided.

  FIG. 11 is a block diagram illustrating functions of the control unit 4 illustrated in FIG. 1, and FIG. 11 also illustrates the configuration of the printing apparatus 1 connected to the control unit 4. The control unit 4 includes a drawing control unit 41 that performs control related to the ejection of ink from the inkjet heads 32 of the four inkjet head units 31 (see FIG. 2), and a movement control unit that performs movement control on the transport unit 27. 42. The drawing control unit 41 is connected to the first drive circuit 335a of the first print head 33a of each inkjet head 32, and controls the plurality of first drive units 334a via the first drive circuit 335a. For convenience of illustration, FIG. 11 shows only the first drive circuit 335a and the first drive unit 334a provided in one first print head 33a (the second drive circuit 335b and the second drive circuit 335b of the second print head 33b described later). The same applies to the drive unit 334b).

  Each of the plurality of first drive units 334a (see FIG. 10C) is a piezoelectric element (piezo element), and each first drive unit 334a is deformed by the control by the drawing control unit 41 via the first drive circuit 335a, FIG. In the vicinity of the first discharge port 331a corresponding to each first drive unit 334a shown in C, the volume of the first discharge channel 332a (more specifically, provided near the first discharge port 331a of the first discharge channel 332a). Chamber volume) is reduced. As a result, pressure is applied to the ink in the vicinity of the first ejection port 331a corresponding to each first drive unit 334a (that is, the ink in the chamber of the first ejection channel 332a that guides ink to the first ejection port 331a). A minute droplet of ink is ejected from the first ejection port 331a. Then, when the shape of the first driving unit 334a is restored, the volume of the first ejection channel 332a is restored to the original in the vicinity of the first ejection port 331a corresponding to the first driving unit 334a, and the volume of the ejected ink is small. The same amount of ink as the droplet is supplied from the first head end channel 333a to the first ejection channel 332a.

  In the first print head 33a, a small amount of ink droplets are ejected by a predetermined amount of deformation of the first drive unit 334a, and ink is supplied to the first ejection channel 332a by the deformation of the first drive unit 334a. Done during a long time. In other words, when the first drive unit 334a vibrates with a predetermined amplitude (hereinafter referred to as “ejection amplitude”), a minute droplet of ink from the first ejection port 331a corresponding to the first drive unit 334a. Is discharged.

  FIG. A and FIG. As shown in B, the second print head 33b arranged in the (−Y) direction substantially perpendicular to the arrangement direction of the plurality of first discharge ports 331a (see FIG. 8.A) with respect to the first print head 33a. The structure is substantially the same as the structure of the first print head 33a. FIG. As shown in B, the second print head 33b is directed toward the plurality of second discharge ports 331b and the plurality of second discharge ports 331b arranged at the same pitch as the first discharge ports 331a in the arrangement direction. A plurality of second ejection channels 332b that guide ink in the (−Z) direction, and a second ink that guides ink parallel to the arrangement direction of the plurality of second ejection ports 331b and is connected to the plurality of second ejection ports 331b. A head end channel 333b is provided. FIG. A and FIG. As shown in B, the plurality of first discharge ports 331a of the first print head 33a is (−X) half the pitch of the discharge ports with respect to the plurality of second discharge ports 331b of the second print head 33b. It is arranged at a position shifted in the direction.

  FIG. As shown in B, the second print head 33b is provided in the vicinity of the plurality of second discharge ports 331b of the plurality of second discharge channels 332b and discharges micro droplets of ink from the plurality of second discharge ports 331b. A second drive unit 334b (see FIG. 10B), which is a plurality of piezoelectric elements, and a second drive circuit 335b that controls (that is, drives) the plurality of second drive units 334b. Actually, the plurality of second drive units 334b of the second print head 33b are controlled by the drawing control unit 41 of the control unit 4 via the second drive circuit 335b as shown in FIG.

  Similarly to the first print head 33a, the second print head 33b is similar to FIG. When each of the second drive units 334b shown in B is deformed, pressure is applied to the ink in the vicinity of the second discharge port 331b in the second discharge flow path 332b corresponding to each of the second drive units 334b, and the second discharge port. Ink droplets are ejected from 331b. That is, when each second drive unit 334b vibrates at the discharge amplitude, ink droplets are ejected from the second ejection port 331b corresponding to each second drive unit 334b.

  FIG. A and FIG. As shown in B, the intermediate support member 34 has a first attachment surface 341 that is a (+ Y) side surface to which the first print head 33a is attached, and a (−Y) side to which the second print head 33b is attached. A second mounting surface 342 that is a surface is provided. In the first print head 33a, a first drive circuit 335a fixed on a thin wiring board is formed as shown in FIG. As shown to A, it is contacting the intermediate support member 34 indirectly through the said wiring board, and can be in the state in which heat conduction is possible between the intermediate support members 34. Similarly to the first drive circuit 335a, the second drive circuit 335b of the second print head 33b is also indirectly in contact with the intermediate support member 34 via the wiring board, and between the second support circuit 34 and the intermediate support member 34. Heat conduction is possible.

  In the inkjet head 32, each of the first drive circuit 335a and the second drive circuit 335b only needs to be in contact with the intermediate support member 34 in a state where heat conduction can be performed between the first support circuit 335a and the second drive circuit 335b (that is, intermediate support member 34). For example, the intermediate support member 34 may be directly contacted.

  As shown in FIG. 9, the intermediate support member 34 includes a common supply channel 343, a common recovery channel 344, and a circuit cooling channel 345 between the first mounting surface 341 and the second mounting surface 342. The common supply flow path 343 is connected to the ink introduction pipe 3131 via an ink supply port 3431 provided between the first attachment surface 341 and the second attachment surface 342 on the (+ Z) side of the intermediate support member 34. . The circuit cooling flow path 345 is connected to the ink outlet tube 3121 via an ink discharge port 3451 provided between the first mounting surface 341 and the second mounting surface 342 on the (+ Z) side of the intermediate support member 34. .

  The common supply flow path 343 is shown in FIG. As shown to A, it connects with the (+ X) side edge part of each of the 1st head end part flow path 333a of the 1st print head 33a, and the 2nd head end part flow path 333b of the 2nd print head 33b. The ink introduced into the common supply channel 343 from the ink supply tank 313 (see FIG. 4) (that is, from the outside of the inkjet head 32) via the ink introduction tube 3131 and the ink supply port 3431 shown in FIG. . As shown in FIG. 10A, the first head end channel 333a and the second head end channel 333b are guided to FIG. A to FIG. The ink is guided from the (+ X) side of the inkjet head 32 to the (−X) side by the first head end channel 333a and the second head end channel 333b shown in FIG.

  The common recovery channel 344 is shown in FIG. As shown to D, it connects to the (-X) side edge part of each of the 1st head end part channel 333a and the 2nd head end part channel 333b. Ink from the first head end channel 333a and the second head end channel 333b is guided to the common recovery channel 344, and FIG. A to FIG. The ink is guided from the (−X) side of the inkjet head 32 to the (+ X) side by the common recovery flow path 344 shown in D.

  In the intermediate support member 34, FIG. A to FIG. As shown in FIG. 10D, the circuit cooling channel 345 is provided on the (+ Z) side of the common recovery channel 344, and FIG. As shown in A, the circuit cooling channel 345 is connected to the (+ X) side end of the common recovery channel 344. The ink that has flowed from the first head end channel 333a and the second head end channel 333b into the circuit cooling channel 345 via the common recovery channel 344 is shown in FIG. A to FIG. The ink is guided from the (+ X) side of the inkjet head 32 to the (−X) side by the circuit cooling channel 345 shown in E.

  FIG. B and FIG. As shown in C, the circuit cooling flow path 345 is disposed between the first drive circuit 335a and the second drive circuit 335b and in the vicinity of the first drive circuit 335a and the second drive circuit 335b. Thermal conduction occurs between the ink flowing through the flow path 345 and the first drive circuit 335a and the second drive circuit 335b, whereby the first drive circuit 335a and the second drive circuit 335b are cooled. In other words, in the inkjet head 32, the first drive circuit 335a and the second drive circuit 335b are allowed to pass through the vicinity of the first drive circuit 335a and the vicinity of the second drive circuit 335b by allowing the ink flowing through the circuit cooling flow path 345 to pass through. To be cooled.

  The ink used for cooling the first drive circuit 335a and the second drive circuit 335b is guided to the (−X) side of the inkjet head 32 by the circuit cooling flow path 345, and FIG. 4 is discharged to the ink recovery unit 312 shown in FIG. 4 (that is, to the outside of the inkjet head 32) via the ink discharge port 3451 and the ink outlet tube 3121 shown in E, and the circulation line 51 ( (See FIG. 5).

  As described above, the ink used in the printing apparatus 1 is an ultraviolet curable ink, and the temperature of ink that is appropriately ejected (hereinafter referred to as “appropriate ejection temperature”) is higher than room temperature, and is about 40 to 50 ° C. In the printing apparatus 1, 40 to 45 ° C. ink is supplied to the ink supply tank 313 of the inkjet head unit 31 and supplied to the plurality of inkjet heads 32 by the ink circulation mechanism 5 shown in FIG. 5. The ink supplied to the inkjet head 32 generates heat from the first drive unit 334a and the second drive unit 334b (see FIGS. 10B and 10C), and the first drive circuit 335a in the circuit cooling channel 345. And the circulation line 51 through the ink recovery unit 312 in a state where the temperature is increased by about 3 to 5 ° C. due to cooling of the second drive circuit 335b (that is, heat conduction from the first drive circuit 335a and the second drive circuit 335b). Led to.

  Then, the ink temperature is lowered by natural cooling by a temperature substantially equal to the above-mentioned increase (about 3 to 5 ° C.) until it flows through the circulation line 51 and is re-supplied to the ink supply tank 313. As a result, ink having an appropriate discharge temperature higher than room temperature is supplied to the inkjet head unit 31 without heating and cooling the ink in the circulation line 51. For this reason, in the ink circulation mechanism 5, the heater 531 of the external ink tank 53 is normally used only for heating the ink when the printing apparatus 1 is started up.

  When printing is performed by the printing apparatus 1 illustrated in FIG. 1, the transport unit 27 is controlled by the movement control unit 42 (see FIG. 11) of the control unit 4, so that the base material 9 is in the scanning direction (that is, FIG. 1 in the Y direction, and in a direction substantially perpendicular to the arrangement direction of the plurality of first ejection ports 331a and the plurality of second ejection ports 331b of each inkjet head 32. In addition, the drawing control unit 41 (see FIG. 11) performs the first drive circuit 335a and the first drive circuit 335a of each inkjet head 32 based on the image data to be printed on the substrate 9 in parallel with the movement of the substrate 9. By controlling the second drive circuit 335b (see FIGS. 8.A and 8.B), each time the base material 9 moves by a predetermined distance in the scanning direction, the plurality of first drive units 334a and the plurality of second drive units 334a are moved. The drive unit 334b (hereinafter, when there is no need to distinguish between the first drive unit 334a and the second drive unit 334b, it is also simply referred to as “drive unit”. The first discharge port 331a, the second discharge port 331b, and The same applies to the first discharge flow path 332a and the second discharge flow path 332b.) Among the first discharge flow path 332a and the second discharge flow path 332b), a pulse signal is applied to the drive unit corresponding to the discharge port from which the ink is discharged. When a pulse signal is applied to the drive unit, the drive unit, which is a piezoelectric element, vibrates with a predetermined amplitude, and a minute droplet of ink is ejected from the ejection port corresponding to the drive unit and applied to the substrate 9. Thus, an image is printed on the substrate 9.

  As described above, in each inkjet head 32 of the inkjet head unit 31 of the printing apparatus 1, the first print head 33a and the second print head 33b are respectively attached to both sides in the scanning direction of the intermediate support member 34. The intermediate support member 34 is formed with a flow path (that is, a common recovery flow path 344 and a circuit cooling flow path 345) into which ink derived from the first print head 33a and the second print head 33b flows.

  Thereby, the structure of the inkjet head 32 is simplified as compared with the case where the flow path into which the ink derived from the first print head flows and the flow path into which the ink derived from the second print head flows are provided separately. In addition, the inkjet head 32 can be miniaturized. In particular, a flow path into which ink derived from the first print head flows is provided on the (+ Y) side of the first print head (that is, the side opposite to the intermediate support member), and the ink derived from the second print head. Compared to the case where the flow path into which the ink flows is provided on the (−Y) side of the second print head (that is, the side opposite to the intermediate support member), the inkjet head 32 can be downsized in the Y direction which is the scanning direction. it can.

  In addition, the flow path from the first head end flow path 333a of the first print head 33a to the ink recovery section 312 through the common recovery flow path 344, the circuit cooling flow path 345, and the ink outlet pipe 3121 is the second print. The pressure loss in the flow path related to the ink discharge of the first print head 33a and the second print head 33b is made common with the flow path from the second head end flow path 333b of the head 33b to the ink recovery section 312. Are equal to each other. Thereby, the uniformity of the ink flow rate in the first head end channel 333a and the second head end channel 333b is improved, and printing is performed due to the difference in the ink discharge amount between the first print head 33a and the second print head 33b. Unevenness is prevented.

  Furthermore, the circuit cooling flow path 345 provided in the intermediate support member 34 causes the ink flowing from the first head end flow path 333 a and the second head end flow path 333 b to substantially contact the intermediate support member 34. By passing the vicinity of the first drive circuit 335a and the second drive circuit 335b, the first print circuit 335a and the second drive circuit 335b can be cooled without first providing a dedicated mechanism for cooling the first print circuit 335a and the second drive circuit 335b. The first drive circuit 335a and the second drive circuit 335b provided in the head 33a and the second print head 33b can be easily cooled. As a result, the ink jet head 32 can be further downsized.

  In the inkjet head 32, a common supply channel 343 that guides the ink supplied from the ink supply tank 313 to the first head end channel 333 a and the second head end channel 333 b is formed in the intermediate support member 34. As a result, the structure of the inkjet head 32 can be further simplified, and the inkjet head 32 can be further miniaturized. In particular, a flow path through which ink supplied to the first print head flows is provided on the (+ Y) side of the first print head, and a flow path through which ink supplied to the second print head flows is (− The inkjet head 32 can be further reduced in size in the scanning direction as compared with the case where it is provided on the Y) side.

  A flow path from the ink supply tank 313 to the first head end flow path 333a of the first print head 33a through the ink introduction pipe 3131 and the common supply flow path 343 is connected to the second print head. By sharing the flow path to the second head end flow path 333b of 33b, pressure losses in the flow paths related to the ink supply to the first print head 33a and the second print head 33b become equal to each other. Thereby, the uniformity of the ink flow rate in the first head end channel 333a and the second head end channel 333b is further improved, and due to the difference in the ink discharge amount between the first print head 33a and the second print head 33b. Uneven printing can be prevented more reliably.

  In the intermediate support member 34, an ink supply port 3431 through which ink is introduced into the common supply channel 343 and an ink discharge port 3451 through which ink is discharged from the circuit cooling channel 345 are connected to the first mounting surface 341 and the first support surface 341. 2 between the two attachment surfaces 342. Thereby, the flow path related to the supply of ink to the ink jet head 32 and the flow path related to the discharge of ink from the ink jet head 32 form the first mounting surface 341 and the second mounting surface 342 of the intermediate support member 34. Since the connection is made in between, the structure related to the connection is suppressed from projecting to the (+ Y) side from the first print head 33a and the (−Y) side from the second print head 33b. As a result, downsizing of the inkjet head 32 in the scanning direction is more reliably realized.

  Note that the ink supply port 3431 and the ink discharge port 3451 are not necessarily provided between the first mounting surface 341 and the second mounting surface 342 of the intermediate support member 34, but the first print head 33a and the second print head 33a. A position between the first attachment surface 341 and the second attachment surface 342 in the Y direction in which the heads 33b are arranged (for example, between the first attachment surface 341 and the second attachment surface 342 in the Y direction, and It is preferable that the first mounting surface 341 and the second mounting surface 342 are provided at the (+ X) side or (−X) side) in the X direction. Thereby, similarly to the above, downsizing of the inkjet head 32 in the scanning direction is more reliably realized.

  In the inkjet head 32, the plurality of first ejection ports 331a of the first print head 33a are shifted from the plurality of second ejection ports 331b of the second print head 33b by half the pitch of the ejection ports in the arrangement direction. By arranging, the printing resolution can be easily improved. Also, it is difficult for an ink jet head of a type that discharges ink from the first discharge port 331a and the second discharge port 331b by a piezoelectric element to heat the ink and discharge the ink by the pressure of an ink bubble (bubble). In addition, it is possible to easily discharge such a low heat resistant ink.

  In the printing apparatus 1, as described above, when the inkjet head 32 is reduced in size in the scanning direction, each inkjet head unit 31 including the plurality of inkjet heads 32 is also reduced in size in the scanning direction. In the inkjet head unit 31, a plurality of inkjet heads 32 are arranged in the X direction so as to be alternately positioned on the (−Y) side and the (+ Y) side of the center rib 311, and each inkjet head 32 is related to the X direction. It is arranged so that at least part of it overlaps with the adjacent inkjet head 32 in the Y direction which is the scanning direction. For this reason, the size reduction in the scanning direction of the inkjet head unit 31 is efficiently realized by the size reduction in the scanning direction of the inkjet head 32.

  In the ink jet head unit 31, the ink supply tank 313 and the plurality of ink jet heads 32 are individually connected, and the ink recovery unit 312 and the plurality of ink jet heads 32 are individually connected. For this reason, it is not necessary to provide a common flow path for connecting the plurality of ink jet heads and the ink supply tank or the ink recovery unit to the mounting member to which the plurality of ink jet heads are attached, and the center rib 311 can be downsized in the scanning direction. Can do. As a result, the inkjet head unit 31 can be further downsized in the scanning direction.

  In the inkjet head unit 31, a plurality of inkjet heads 32 are linearly connected to the ink supply tank 313 with the same flow path length and the same flow path diameter, and are connected to the ink recovery unit 312 with the same flow path length and the same flow path diameter. Connected in a straight line. Thereby, the uniformity of the pressure loss in the plurality of inkjet heads 32 is improved, and the flow rate of the ink flowing through the plurality of inkjet heads 32 becomes uniform as described above. As a result, printing unevenness due to the difference in the ink ejection amounts of the plurality of inkjet heads 32 is prevented.

  In the printing apparatus 1, downsizing of the ejection mechanism 3 in the scanning direction is realized by downsizing each inkjet head unit 31 in the scanning direction. As a result, the length in the scanning direction of the portion of the base material 9 that overlaps the ejection mechanism 3 is shortened, and therefore, when the base material 9 moves in the scanning direction, meandering of the base material 9 or uneven feeding of the base material 9 occurs. However, the relative position of the base material 9 with respect to the discharge mechanism 3 on the (+ Y) side of the discharge mechanism 3 may be significantly different from the relative position of the base material 9 with respect to the discharge mechanism 3 on the (−Y) side of the discharge mechanism 3. Is prevented. As described above, in the printing apparatus 1, even when the meandering or feeding unevenness of the base material 9 occurs, the influence of the meandering or feeding unevenness is reduced to suppress the deterioration of the printing quality on the base material 9. it can.

  In the printing apparatus 1, ultraviolet curable ink having an appropriate discharge temperature higher than room temperature is used, so that the ink flowing through the circulation line 51 from the ink recovery unit 312 to the ink supply tank 313 is naturally cooled. Therefore, assuming that the ink with the proper discharge temperature is discharged from each inkjet head to the ink collection unit, the ink whose temperature has been lowered by natural cooling is heated to the discharge appropriate temperature in an ink circulation mechanism, an ink supply tank, etc. It is necessary to supply the head.

  On the other hand, in the printing apparatus 1 according to the present embodiment, in each inkjet head 32, the first head end channel 333a and the second head end channel 333b of the first print head 33a and the second print head 33b. The first drive circuit 335a and the second drive circuit 335b are cooled by the ink derived from the above, and the temperature of the ink rises. Accordingly, the temperature of the ink discharged from the ink jet head 32 to the ink recovery unit 312 is higher than the appropriate discharge temperature, and the ink is re-supplied to the ink supply tank 313 while being naturally cooled to the appropriate discharge temperature. In the circulation mechanism 5, heating of ink by the heater 531 is almost unnecessary. In this way, the printing apparatus 1 can maintain the temperature of the ink supplied to each inkjet head 32 at an appropriate discharge temperature without heating the ink with a heater or the like. Particularly suitable for printing with a reactive ink.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  For example, in the printing apparatus 1 shown in FIG. 1 (so-called roll-to-roll printing apparatus), the base material 9 is moved in the scanning direction intersecting the arrangement direction of the plurality of ejection openings by the transport unit 27 that moves the base material 9 in the scanning direction. 9 moves at a constant speed with respect to the ejection mechanism 3, but the printing apparatus 1 may be provided with a mechanism for moving the ejection mechanism 3 in the scanning direction. Further, as in the printing apparatus 1a shown in FIG. 12 (so-called sheet-fed printing apparatus), the stage 21 that holds the rectangular base material 9 and the stage 21 in the scanning direction (Y direction in FIG. 12). A moving stage moving mechanism 22 may be provided. As described above, the scanning mechanism that moves the base material 9 in the scanning direction relative to the ejection mechanism 3 can be realized in various configurations.

  In the printing apparatus 1a shown in FIG. 12, for example, printing may be performed on the base material 9 having a width larger than the width in the X direction of the ejection mechanism 3. In this case, a mechanism for moving the stage 21 or the discharge mechanism 3 in the X direction in FIG. 12 is provided, and every time the base material 9 moves once in the Y direction that is the scanning direction (that is, the base material of the discharge mechanism 3). Every time the scanning with respect to 9 is completed), the substrate 9 or the ejection mechanism 3 moves by a predetermined distance in the X direction, and printing is repeated. In such a printing apparatus (a so-called shuttle type printing apparatus), as described above, the ejection mechanism 3 is downsized in the scanning direction, so that the moving distance of the base material 9 in the scanning direction is shortened and the printing efficiency is increased. Is improved.

  The printing medium in the above-described printing apparatus may be a plate-like member or printing paper formed of plastic in addition to the sheet-like base material 9. In the printing apparatus, ink other than ultraviolet curable ink may be used for printing.

1 is a perspective view illustrating an appearance of a printing apparatus according to an embodiment. It is a bottom view of a discharge mechanism. It is a bottom view of an inkjet head unit. It is a front view of an inkjet head unit. It is a figure which shows an inkjet head unit and an ink circulation mechanism. It is a front view of an inkjet head. It is a side view of an inkjet head. It is a disassembled side view of an inkjet head. FIG. 3 is a front view of a first print head. It is a rear view of a 2nd print head. It is a front view of an intermediate support member. It is a longitudinal cross-sectional view of an inkjet head. It is a longitudinal cross-sectional view of an inkjet head. It is a longitudinal cross-sectional view of an inkjet head. It is a longitudinal cross-sectional view of an inkjet head. It is a longitudinal cross-sectional view of an inkjet head. It is a block diagram which shows the function of a control unit. It is a perspective view which shows the other example of a printing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Printing apparatus 9 Base material 27 Conveyance part 31 Inkjet head unit 32 Inkjet head 33a 1st print head 33b 2nd print head 34 Intermediate support member 38 Lamp head unit 51 Circulation line 312 Ink collection part 313 Ink supply tank 331 Ejection port 331a First discharge port 331b Second discharge port 332a First discharge channel 332b Second discharge channel 333a First head end channel 333b Second head end channel 334a First drive unit 334b Second drive unit 335a First 1 drive circuit 335b 2nd drive circuit 341 1st mounting surface 342 2nd mounting surface 343 Common supply flow path 345 Circuit cooling flow path 3431 Ink supply port 3451 Ink discharge port

Claims (9)

An inkjet head that ejects micro droplets of ink from a plurality of ejection openings toward a printing medium in an inkjet printing apparatus,
A first print head having a plurality of first ejection openings arranged in a predetermined arrangement direction;
A second print head having a plurality of second discharge ports arranged in the arrangement direction and arranged in a direction substantially perpendicular to the arrangement direction with respect to the first print head;
An intermediate support member disposed between the first print head and the second print head to which the first print head and the second print head are attached;
With
The first print head comprises:
A plurality of first discharge channels for guiding ink toward the plurality of first discharge ports;
A first head end channel that guides ink parallel to the arrangement direction and is connected to the plurality of first ejection channels;
A plurality of first drive units that are provided in the vicinity of the plurality of first discharge ports of the plurality of first discharge channels and that discharge micro droplets of ink from the plurality of first discharge ports;
A first drive circuit for controlling the plurality of first drive units;
With
The second print head comprises:
A plurality of second discharge channels for guiding ink toward the plurality of second discharge ports;
A second head end channel that guides ink parallel to the arrangement direction and is connected to the plurality of second ejection channels;
A plurality of second drive units that are provided in the vicinity of the plurality of second discharge ports of the plurality of second discharge channels and that discharge micro droplets of ink from the plurality of second discharge ports;
A second drive circuit for controlling the plurality of second drive units;
With
The first drive circuit and the second drive circuit are substantially in contact with the intermediate support member;
The intermediate driving member passes the ink flowing in from the first head end channel and the second head end channel through the vicinity of the first drive circuit and the second drive circuit, so that the first drive is performed. An inkjet head comprising a circuit cooling flow path for cooling the circuit and the second drive circuit. The inkjet head according to claim 1,
The inkjet head according to claim 1, wherein the intermediate support member further includes a common supply channel that guides ink supplied from the outside to the first head end channel and the second head end channel. The inkjet head according to claim 2,
The intermediate support member is
In the direction in which the first print head and the second print head are arranged, the first print head is provided at a position between a first attachment surface to which the first print head is attached and a second attachment surface to which the second print head is attached. An ink supply port through which ink guided to the common supply channel is introduced;
Ink drainage that is provided at a position between the first mounting surface and the second mounting surface in a direction in which the first printhead and the second printhead are arranged and that discharges ink from the circuit cooling channel. Exit,
An inkjet head characterized by further comprising: The inkjet head according to any one of claims 1 to 3,
The plurality of first discharge ports and the plurality of second discharge ports are arranged at the same pitch in the arrangement direction, and the plurality of first discharge ports in the arrangement direction are the plurality of second discharge ports. An ink jet head, wherein the ink jet head is disposed at a position shifted by half of the pitch. The inkjet head according to any one of claims 1 to 4,
Each of the plurality of first drive units and each of the plurality of second drive units are piezoelectric elements,
By deforming each first drive unit, pressure is applied to the ink in the vicinity of the first ejection port corresponding to each first drive unit, and a minute droplet of ink is ejected from the first ejection port,
By deforming each second driving unit, pressure is applied to the ink in the vicinity of the second ejection port corresponding to each second driving unit, and a minute droplet of ink is ejected from the second ejection port. Inkjet head characterized. A head unit that ejects micro droplets of ink from a plurality of ejection openings toward a print medium in an inkjet printing apparatus,
An ink jet head according to any one of claims 1 to 5;
Another inkjet head having the same structure as the inkjet head and at least partially overlapping the inkjet head in a direction in which the first print head and the second print head are arranged;
An ink supply tank for storing ink to be supplied to the inkjet head and the other inkjet head;
An ink recovery unit into which ink discharged from the inkjet head and the other inkjet head flows;
A head unit comprising: A head unit that ejects micro droplets of ink from a plurality of ejection openings toward a print medium in an inkjet printing apparatus,
An inkjet head according to claim 3;
Another inkjet head having the same structure as the inkjet head and at least partially overlapping the inkjet head in a direction in which the first print head and the second print head are arranged;
An ink supply tank for storing ink to be supplied to the inkjet head and the other inkjet head;
An ink recovery unit into which ink discharged from the inkjet head and the other inkjet head flows;
With
The ink supply port of the inkjet head and the other inkjet head and the ink supply tank are linearly connected with the same channel length and channel diameter,
An ink discharge port of the ink jet head and the other ink jet head and the ink recovery portion are linearly connected with the same flow path length and flow path diameter. An inkjet printing apparatus,
The head unit according to claim 6 or 7,
A circulation line for guiding ink from the ink recovery part of the head unit to the ink supply tank;
A scanning mechanism that moves a print medium relative to the head unit in a scanning direction that intersects the arrangement direction;
A printing apparatus comprising: The printing apparatus according to claim 8, wherein
An ultraviolet irradiation unit for irradiating the ink on the printing medium with ultraviolet rays;
A printing apparatus, wherein the ink is an ultraviolet curable ink.

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