JP6260110B2 - Liquid ejection device - Google Patents

Description

  The present invention relates to a liquid ejection apparatus.

  As a liquid discharge head that discharges liquid, Japanese Patent Application Laid-Open No. 2004-133867 discloses an ink jet that can perform multicolor printing by discharging four colors of ink onto a recording medium that is transported in a predetermined transport direction. A head is disclosed. The four color inks are specifically three color inks of cyan (blue), magenta (red), and yellow, and black ink used for monochrome printing.

  The ink-jet head disclosed in Patent Document 1 has three color nozzle arrays that respectively eject three color inks of cyan, magenta, and yellow, and a black nozzle array that ejects black ink. The color nozzle row is one row for each color, while the black nozzle row is provided in three rows. In addition, the position of the nozzles in the arrangement direction is identical between one of the three black nozzle rows and the three color nozzle rows.

  The other two black nozzle rows are shifted in the arrangement direction with respect to the total of four nozzle rows of the three color nozzle rows and the one black nozzle row with the same nozzle position. Has been. As a result, on one side in the arrangement direction (upper side in FIG. 3 of Patent Document 1), four nozzles positioned at the respective ends of the four nozzle rows correspond to the other two black nozzle rows. It is arranged in a state where the positions in the arrangement direction are aligned at a position on one side of the end nozzle. Further, on the other side in the arrangement direction (lower side in FIG. 3 of Patent Document 1), the nozzles located at the ends of the two black nozzle rows are arranged at the ends of the four nozzle rows at which the nozzle positions coincide. It arrange | positions so that it may protrude to the said other side rather than a nozzle. Note that Patent Document 1 does not specifically disclose the relationship between the side where the nozzles at the ends of the four nozzle rows are aligned and the conveyance direction of the recording medium.

JP-A-63-13752 (FIGS. 1 and 3)

  By the way, on the upstream side in the transport direction of the ink jet head, the recording medium sent toward the ink jet head is likely to float and flutter. If the recording medium comes into contact with the nozzles of the ink jet head due to the floating or fluttering, there is a possibility that ejection failure may occur in the nozzles. For this reason, the nozzles at the end of each nozzle row are desired to be arranged as far as possible from the upstream edge in the transport direction of the ink jet head, but in this case, there is a problem that the ink jet head is enlarged in the transport direction. Therefore, the inventor of the present application, in particular, in the head of the nozzle arrangement as in Patent Document 1, examined the separation of the nozzle position from the upstream edge in the transport direction as much as possible without increasing the size of the head in the transport direction. The present invention has been reached.

  An object of the present invention is to suppress as much as possible that a discharge target such as a recording medium sent from the upstream side contacts a nozzle without increasing the size of the liquid discharge head in the transport direction.

According to a first aspect of the present invention, there is provided a liquid discharge apparatus including: a liquid discharge head having a plurality of nozzles arranged along a first direction; and a target to be discharged by the liquid discharged from the liquid discharge head. A transport unit that transports the liquid discharge head from the one side in the first direction to the other side;
The liquid discharge heads are arranged at predetermined intervals in the first direction as well as a first nozzle row composed of a plurality of first nozzles arranged at predetermined intervals in the first direction to discharge the first liquid. A plurality of second nozzle rows composed of a plurality of second nozzles for discharging the second liquid,
The plurality of second nozzle rows include the second nozzle row at the same position where the nozzle positions in the first direction coincide with the first nozzle row, and the nozzle positions in the first direction with respect to the first nozzle row. And the second nozzle row at different positions shifted from each other,
The first nozzle located at the other end of the first nozzle row and the second nozzle located at the other end of the second nozzle row at the same position are the second nozzle row at the different position. A second nozzle that is arranged at a position on the other side of the first direction with respect to the second nozzle in a state where the positions in the first direction are aligned and located at the end on the one side of the second nozzle row at the different position. Is arranged at a position on the one side in the first direction with respect to the first nozzle of the first nozzle row and the second nozzle of the second nozzle row at the same position. is there.

  In the present invention, the position of the first nozzle at the end of the first nozzle row and the position of the second nozzle at the end of the second nozzle at the same position on the other side in the first direction, that is, the downstream side in the transport direction of the discharged object. It's all there. And in the conveyance direction upstream of the opposite side, the 2nd nozzle of a different position 2nd nozzle row is arrange | positioned so that it may protrude rather than the nozzle of the end of another nozzle row. As a result, the number of nozzles arranged closer to the upstream edge of the liquid discharge head in the transport direction is reduced, and even if the discharge target floats or flutters, it is possible to suppress the discharge target from contacting the nozzle as much as possible. Is done.

  The liquid ejection apparatus according to a second aspect is the liquid ejection device according to the first aspect, wherein the second nozzle row at a different position is in a second direction orthogonal to the first direction among all the nozzle rows of the liquid ejection head. It is arrange | positioned in the position of an edge, It is characterized by the above-mentioned.

  In particular, the discharge target conveyed to the liquid discharge head is likely to float and flutter at the central portion in the second direction orthogonal to the conveyance direction. In this regard, in the present invention, the different-position second nozzle row in which the second nozzle at the end is arranged most upstream in the transport direction is located at the end in the second direction among all the nozzle rows. On the end side in the second direction, the discharged object is less likely to float and flutter compared to the center portion, and therefore the discharged object is less likely to contact the second nozzle located at the end of the second nozzle row at the different position. .

According to a third aspect of the present invention, in the first or second aspect, the liquid discharge head includes a flow path structure having a liquid flow path including the plurality of nozzles, and the flow path structure. A discharge drive unit that is disposed on a surface opposite to the liquid discharge surface and discharges liquid from each of the plurality of nozzles;
The apparatus further includes a flexible wiring board connected to the ejection driving unit of the liquid ejection head, wherein the ejection driving unit is arranged in the first direction corresponding to the plurality of first nozzles. A first terminal row comprising terminals, and a second terminal row comprising a plurality of second connection terminals arranged in the first direction corresponding to the plurality of second nozzles, respectively.
The flexible wiring board is connected to the first connection terminal and the second connection terminal in a state of covering the discharge driving unit, and is drawn from the discharge driving unit to the other side in the first direction,
For the second terminal row corresponding to the first terminal row and the second nozzle row at the same position, the discharge driving portion and the flexible wiring board are disposed on both outer sides of the terminal row in the first direction. Reinforcing portions that reinforce bonding are provided, and the second terminal row corresponding to the differently located second nozzle row is provided with the reinforcing portion only on the other side in the first direction, and on the one side. Is characterized in that the reinforcing part is not provided.

  In the present invention, the flexible wiring board is connected to the ejection driving unit of the liquid ejection head in a state of covering the ejection driving unit. Further, the flexible wiring board connected to the ejection driving unit is configured such that the positions of the nozzles at the respective ends of the second nozzle array at the same position as the first nozzle array of the liquid ejection head are aligned with each other in the first direction. Has been pulled from.

  In addition, for each of the first terminal row corresponding to the first nozzle row and the second terminal row corresponding to the second nozzle row, a reinforcing portion is provided on the outer side in the first direction from the connection terminal located at the end. ing. Here, on the other side in the first direction from which the flexible wiring board is pulled out, the flexible wiring board is easily peeled off, and therefore, reinforcing portions are provided for all the terminal rows. On the other hand, on the one side in the first direction, the flexible wiring board is less likely to be peeled off as far as the other side, that is, the drawer side of the flexible wiring board. is there.

  In the present invention, the second terminal row corresponding to the different-position second nozzle row arranged so that the second nozzle at the end protrudes to the one side, the reinforcing portion only on the other side from which the wiring board is drawn out. And the reinforcing part is not provided on the one side. Thereby, compared with the case where a reinforcement part is provided in the both outer sides about all the terminal rows, the enlargement of the liquid discharge head and flexible wiring board in a 1st direction is suppressed. Further, even if the reinforcing portion on the one side of the second terminal row is omitted, the reinforcing portion is provided on the other terminal row, so that it is possible to sufficiently prevent peeling of the wiring board on the one side.

In any one of the first to third inventions, a liquid ejection device according to a fourth aspect of the present invention includes a plurality of first nozzle rows that eject a plurality of types of the first liquid, and the different types of the first nozzles. The positions of the first nozzles in the first direction coincide between the first nozzle rows that discharge liquid, respectively, and the plurality of first nozzle rows and the plurality of second nozzle rows have nozzles. The number of columns is equal,
The plurality of first nozzle rows are arranged side by side in the second direction on one side in a second direction orthogonal to the first direction, and the plurality of second nozzle rows are arranged on the other side in the second direction. Arranged side by side in the second direction,
The liquid ejection head further includes a cap member that is mounted so as to cover the plurality of nozzles, and the cap member includes a first cap portion that covers the plurality of first nozzle rows in common, and the plurality of second nozzles. And a second cap portion that covers the nozzle rows in common.

  In the present invention, the number of nozzle rows is equal between the plurality of first nozzle rows that respectively discharge a plurality of types of first liquids and the plurality of second nozzle rows that discharge the second liquid. That is, the number of first nozzle rows covered with the first cap portion of the cap member is equal to the number of second nozzle rows covered with the second cap portion. Accordingly, the sizes of the first cap portion and the second cap portion can be made substantially equal. Thereby, when the cap member is mounted on the liquid discharge head, the first cap portion and the second cap portion are pressed against the liquid discharge head with substantially equal force. Deformation of the liquid ejection surface is suppressed. Further, since the pressing force of the cap member is made uniform, the sealing performance is also improved.

  According to the present invention, the first nozzle at the end of the first nozzle row and the second nozzle at the end of the second nozzle at the same position on the other side in the first direction, that is, downstream in the transport direction of the discharged object. The position is aligned. On the upstream side in the transport direction on the opposite side, the second nozzle at the end of the second nozzle row at the different position is arranged so as to protrude from the nozzle at the end of the other nozzle row. Accordingly, the number of nozzles arranged close to the edge on the upstream side in the transport direction of the liquid discharge head is reduced, and the discharge target that has been sent toward the liquid discharge head is prevented from contacting the nozzle as much as possible.

1 is a plan view illustrating a schematic configuration of an ink jet printer according to an embodiment. It is a front view of a carriage. It is a block diagram which shows roughly the control system of an inkjet printer. It is a top view of an inkjet head. It is the A section enlarged view of FIG. FIG. 6 is a sectional view taken along line VI-VI in FIG. 5. It is the VII-VII sectional view taken on the line of FIG. It is a figure which shows the some nozzle arrangement of an inkjet head.

  Next, an embodiment of the present invention will be described. This embodiment is an example in which the present invention is applied to an ink jet printer that prints an image or the like by ejecting ink onto a recording sheet. FIG. 1 is a plan view showing a schematic configuration of the ink jet printer according to the present embodiment. FIG. 2 is a front view of the carriage. FIG. 3 is a block diagram schematically showing a control system of the ink jet printer. In the following, the front side in FIG. 1 is defined as the upper side, and the other side of the page is defined as the lower side, and the explanation will be made using direction words “up” and “down” as appropriate. As shown in FIG. 1, the inkjet printer 1 includes a platen 2, a carriage 3, an inkjet head 4, a transport mechanism 5, a maintenance mechanism 6, a control device 7, and the like.

  On the upper surface of the platen 2, a recording sheet 100 as a recording medium is placed. The recording paper 100 is transported in the transport direction shown in FIG. 1 by a transport mechanism 5 described later. The carriage 3 is configured to be capable of reciprocating in the scanning direction orthogonal to the transport direction along the two guide rails 10 and 11 in the region facing the platen 2. An endless belt 14 is connected to the end of the carriage 3 on the downstream side in the transport direction. When the endless belt 14 is driven by the carriage drive motor 15, the carriage 3 moves in the scanning direction.

  The inkjet head 4 is attached to the carriage 3 and moves in the scanning direction together with the carriage 3. The ink jet head 4 is connected to ink cartridges 17 of four colors (black, yellow, cyan, magenta) mounted on the printer 1 by a tube (not shown). In the following description, among the four color inks, the three color inks of yellow, cyan, and magenta other than the black ink may be collectively referred to as “color ink”. In addition, for each component of the printer 1, for each of the black (K), yellow (Y), cyan (C), and magenta (M) inks, which ink follows the reference numeral indicating that component. As appropriate, any one of “k” indicating black, “y” indicating yellow, “c” indicating cyan, and “m” indicating magenta is appropriately attached. For example, the ink cartridge 17k refers to the ink cartridge 17 that stores black ink.

A plurality of nozzles 42 are formed on the lower surface of the ink jet head 4 (the surface on the other side of the paper in FIG. 1). Hereinafter, the lower surface of the inkjet head 4 on which the plurality of nozzles 42 are formed is also referred to as an ink ejection surface 4a. The plurality of nozzles 42 formed on the ink ejection surface 4a are arranged along the transport direction and constitute a plurality of nozzle rows 44 arranged in the scanning direction. As shown in FIG. 2, nozzle rows 44y, 44c, and 44m that discharge yellow, cyan, and magenta color inks are arranged in the scanning direction on the right side, and nozzles that discharge black ink on the left side. Rows 44k are arranged side by side in the scanning direction. Details of the configuration of the inkjet head 4 will be described later.

  A rectangular frame-shaped nozzle guide 16 is attached to the inkjet head 4 so as to surround the ink discharge surface 4a. As shown in FIG. 2, the nozzle guide 16 protrudes slightly below the ink ejection surface 4a. The nozzle guide 16 prevents the recording paper 100 conveyed by the conveyance mechanism 5 described below from coming into contact with the ink ejection surface 4a.

  The transport mechanism 5 includes two transport rollers 12 and 13 arranged so as to sandwich the platen 2 in the transport direction. The two transport rollers 12 and 13 are driven in synchronization by a transport motor 19 (see FIG. 3). The transport mechanism 5 transports the recording paper 100 placed on the platen 2 in the transport direction by two transport rollers 12 and 13.

  The maintenance mechanism 6 is disposed at a position outside the area facing the recording paper 100 (on the right side in FIG. 1) in the movement range of the carriage 3 in the scanning direction. The maintenance mechanism 6 includes a cap member 20, a cap drive motor 21 (see FIG. 2), and a suction pump 22.

  The cap member 20 is driven in a vertical direction (a direction perpendicular to the paper surface of FIG. 1) by a cap drive motor 21. When the carriage 3 moves to a position immediately above the maintenance mechanism 6, the ink ejection surface 4 a of the inkjet head 4 faces the cap member 20 as shown in FIG. 2. In this state, when the cap member 20 is driven upward by the cap drive motor 21, the cap member 20 is in close contact with the ink discharge surface 4 a and covers the plurality of nozzles 42. The cap member 20 includes a first cap portion 20a on the right side and a second cap portion 20b on the left side. The 1st cap part 20a and the 2nd cap part 20b are partitioned off by the partition part 20c. When the cap member 20 is in close contact with the ink ejection surface 4a, among the plurality of nozzle rows 44 of the inkjet head 4, the plurality of color nozzle rows 44y, 44c, 44m located on the right side are shared by the first cap portion 20a. Covered. The plurality of black nozzle rows 44k located on the left side are commonly covered by the second cap portion 20b.

  As shown in FIG. 1, a suction pump 22 is connected to the cap member 20. The suction pump 22 is connected to the cap member 20 via the switching device 23. The switching device 23 switches the connection destination of the suction pump 22 between the first cap portion 20a and the second cap portion 20b of the cap member 20.

  In a state where the cap member 20 is in close contact with the ink discharge surface 4a of the inkjet head 4, the suction pump 22 is operated to decompress the inside of the first cap portion 20a or the second cap portion 20b. Then, the ink is forcibly discharged from the plurality of nozzles 42 covered with the cap portion 20a (20b) whose inside is decompressed. By this forced ink discharging operation, bubbles and dust in the ink jet head 4 or ink thickened by drying are discharged from the plurality of nozzles 42, respectively, so that the ejection failure of the nozzles 42 is eliminated.

  3 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an ASIC (Application Specific Integrated Circuit) including various control circuits, and the like. The control device 7 is connected to various devices or drive units of the printer 1 such as the inkjet head 4, the carriage drive motor 15, the transport motor 19, and the suction pump 22. The control device 7 is connected to the operation panel 24 and a PC 25 that is an external device.

  The control device 7 causes the CPU and ASIC to execute various processes according to the program stored in the ROM. For example, the control device 7 controls the inkjet head 4, the carriage drive motor 15, and the like based on the print command transmitted from the PC 25 to print an image or the like on the recording paper 100. In addition, although the control apparatus 7 gave the example which performs various processes by CPU and ASIC, this invention is not limited to this, The control apparatus 7 may be implement | achieved by what hardware constitutions. For example, the processing may be performed by only the CPU or only the ASIC. The functions may be shared by two or more CPUs or two or more ASICs.

  Next, the inkjet head 4 will be described in detail. FIG. 4 is a plan view of the inkjet head. FIG. 5 is an enlarged view of part A of FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5, and FIG. 7 is a sectional view taken along the line VII-VII in FIG. For simplification of the drawing, FIG. 4 shows the COF 60 covering the piezoelectric actuator 31 with a two-dot chain line. In FIG. 5, the COF 63 is not shown. As shown in FIGS. 4 to 7, the inkjet head 4 includes a flow path unit 30 and a piezoelectric actuator 31.

  First, the flow path unit 30 will be described. As shown in FIGS. 6 and 7, the flow path unit 30 has a structure in which five plates 32 to 36 are laminated. The lowermost plate 36 among the five plates 32 to 36 is a nozzle plate 36 in which a plurality of nozzles 42 are formed, and the lower surface of the nozzle plate 36 serves as the ink ejection surface 4a. The remaining four plates 32 to 35 on the upper side are made of a metal material such as stainless steel. In these four metal plates 32 to 35, flow paths such as a manifold 41 and a pressure chamber 43 communicating with the plurality of nozzles 42 are formed.

  Next, the configuration of the ink flow path formed in the flow path unit 30 will be described. As shown in FIG. 4, four ink supply holes 40 are formed in the upper surface of the flow path unit 30 side by side in the scanning direction. Of the four ink supply holes 40, the ink supply hole 40 k located on the left side is larger than the three ink supply holes 40 on the right side. The left ink supply hole 40k is connected to an ink cartridge 17k that stores black ink. The three ink supply holes 40y, 40c, and 40m on the right side are connected to the three ink cartridges 17y, 17c, and 17m that store the three color inks, respectively.

  A total of seven manifolds 41 extending in the transport direction are formed inside the flow path unit 30. Of the seven manifolds 41, the four manifolds 41k1 to 41k4 located on the left side in FIG. 2 are connected to the black ink supply hole 40k. Further, the three manifolds 41y, 41c, 41m located on the right side are connected to the three ink supply holes 40y, 40c, 40m of the color, respectively.

  Further, the flow path unit 30 has a plurality of nozzles 42 opened on the ink discharge surface 4 a on the lower surface thereof, and a plurality of pressure chambers 43 respectively communicating with the plurality of nozzles 42.

  The arrangement of the plurality of nozzles 42 will be described. The plurality of nozzles 42y, 42c, and 42m that discharge three color inks are arranged on the right side in FIG. The plurality of nozzles 42y that discharge yellow ink are arranged on both sides of the yellow manifold 41y to form two nozzle rows 44y1 and 44y2. Similarly, the plurality of nozzles 42c that discharge cyan ink constitute two nozzle rows 44c1 and 44c2 on both sides of the manifold 41c. The plurality of nozzles 42m that eject magenta ink constitute two nozzle rows 44m1 and 44m2 on both sides of the manifold 41m.

  The plurality of nozzles 42k that discharge black ink are arranged in the transport direction on the left side of FIG. 4 to form six nozzle rows 44k1 to 44k6. Six nozzle rows 44k1 to 44k6 are arranged between the four manifolds 41k1 to 41k4. More specifically, two nozzle rows 44k are arranged between two manifolds 41k adjacent in the scanning direction. For example, two nozzle rows 44k1 and 44k2 are arranged between the first manifold 41k1 and the second manifold 41k2 from the left.

  FIG. 8 is a diagram showing the nozzle arrangement of the inkjet head. FIG. 8 shows only a plurality of nozzles 42 extracted from FIG. 4 so that the nozzle arrangement can be easily understood. In the twelve nozzle rows 44 shown in FIG. 8, the arrangement intervals P of the nozzles 42 are all equal. Further, the position of the nozzle 42 is shifted by P / 2 between the two nozzle rows 44 adjacent in the scanning direction. Note that such a set of two nozzle rows 44 is referred to as a nozzle row set 45. That is, one nozzle row set 45y is constituted by the two nozzle rows 44y1 and 44y2 of yellow. Similarly, one nozzle row set 45c is constituted by the two nozzle rows 44c1 and 44c2 of cyan, and one nozzle row set 45m is constituted by the two nozzle rows 44m1 and 44m2 of magenta. Further, the six nozzle rows 44k of black constitute three nozzle row groups 45k1 to 45k3. The arrangement interval of the nozzles 42 in each nozzle row set 45 is half (P / 2) of the arrangement interval P of each nozzle row 44.

  The positions of the nozzles 42 in the transport direction are the same in the three-color nozzle row groups 45y, 45c, 45m and the black nozzle row group 45k3 adjacent thereto. In the black nozzle array set 45k2, the position of the nozzle 42 is shifted by P / 3 on the upstream side in the transport direction with respect to the nozzle array sets 45k3, 45y, 45c, and 45m. Further, with respect to this nozzle row set 45k2, the nozzle row set 45k1 is further shifted by P / 3 on the upstream side in the transport direction.

  As a result, for the color nozzles 42y, 42c, and 42m constituting one nozzle row set 45, the nozzles 42 are arranged at intervals of P / 2 in the transport direction. On the other hand, since the black nozzles 42k constitute three nozzle row groups 45 that are displaced from each other by P / 3 in the transport direction, (P / 2) × (P / 3) = P / 6. The nozzles 42 are arranged at intervals of. That is, the arrangement interval of the black nozzles 42k in the entire six nozzle rows 44k is 1/3 of the arrangement interval of the color nozzles 42y, 42c, and 42m.

  With this configuration, in the case of so-called monochrome printing in which only black ink is used, high-speed and high-resolution printing can be performed by simultaneously using all six nozzle rows 44k1 to 44k6. On the other hand, in the case of so-called color printing using all four colors of ink, the positions of the nozzles 42 y, 44 c, 44 m of the color ink and the nozzles 42 of the six nozzle rows 44 k 1 to 44 k 6 of the black ink coincide. Only two nozzle rows 44k5 and 44k6 of the nozzle row set 45k3 are used. The black nozzle row set 45k3 and the color nozzle row sets 45y, 45c, and 45m, in which the positions of the nozzles 42 coincide, are adjacent to each other in the scanning direction. That is, in color printing, four adjacent nozzle row groups 45k3, 45y, 45c, and 45m are used. According to this configuration, during the color printing, when the carriage 3 moving to the right in FIG. 1 changes its direction to the left, the nozzle array set 45k3 passes the print area of the recording paper 100, that is, the nozzle. The carriage 3 can be reversed to the left in a state in which the column sets 45k1 and 45k2 have not yet passed the printing area. As a result, the time required for reversing the carriage 3 during color printing can be shortened, and the printing speed can be increased.

  Further, the two black nozzle row sets 45k1 and 45k2 are shifted to the upstream side in the transport direction with respect to the color nozzle row sets 45y, 45c, and 45m and the black nozzle row set 45k3. Therefore, on the upstream side in the transport direction, the nozzles 42k positioned at the ends of the two nozzle row groups 45k1 and 45k2 are arranged upstream of the nozzles 42 at the ends of the other nozzle row groups 45 in the transport direction. . On the other hand, on the downstream side in the transport direction, the four nozzles 42 positioned at the ends of the four nozzle row groups 45k3, 45y, 45c, and 45m are downstream in the transport direction from the nozzles 42 at the ends of the other nozzle row groups 45k1 and 45k2. On the side, they are arranged with their positions in the transport direction aligned.

  In the present embodiment, as shown in FIG. 2, nozzle rows 44y, 44c, 44m for color ink covered with the first cap portion 20a of the cap member 20 and nozzles for black ink covered with the second cap portion 20b. In the row 44k, the number of nozzle rows 44 is equal to 6 rows. Accordingly, the sizes of the first cap part 20a and the second cap part 20b are substantially equal. Thus, when the cap member 20 is mounted on the inkjet head 4, the first cap portion 20a and the second cap portion 20b are pressed against the ink discharge surface 4a with substantially equal force, so that the deformation of the ink discharge surface 4a is prevented. It can be suppressed. Further, since the pressing force of the cap member 20 is made uniform, the sealing performance is also improved.

  As shown in FIG. 4, the plurality of pressure chambers 43 are arranged in the transport direction corresponding to the plurality of nozzles 42, respectively. That is, on the right side of FIG. 4, a plurality of pressure chambers 43 respectively communicating with the plurality of color nozzles 42y, 42c, and 42m are arranged in the transport direction so as to partially overlap the manifold 41 in the vertical direction, and are arranged in six rows. It constitutes a pressure chamber row. Also, on the left side of FIG. 4, a plurality of pressure chambers 43 respectively communicating with the plurality of black nozzles 42k are arranged so as to partially overlap the manifold 41 in the vertical direction, and similarly constitute six pressure chamber rows. ing. As shown in FIG. 6, each pressure chamber 43 communicates with a manifold 41 located immediately below it.

  As described above, as indicated by arrows in FIG. 6, a plurality of individual flow paths are formed in the flow path unit 30 so as to branch from the respective manifolds 41 and reach the nozzles 42 through the pressure chambers 43.

  Next, the piezoelectric actuator 31 will be described. As shown in FIGS. 4 to 7, the piezoelectric actuator 31 is disposed on the upper surface of the flow path unit 30 on the side opposite to the ink discharge surface 4a. The piezoelectric actuator 31 includes a diaphragm 50, piezoelectric layers 51 and 52, a plurality of individual electrodes 53, and a common electrode 54.

  The diaphragm 50 is joined to the upper surface of the flow path unit 30 in a state of covering the plurality of pressure chambers 43. The two piezoelectric layers 51 and 52 are laminated on the upper surface of the diaphragm 50. The piezoelectric layers 51 and 52 are each made of a piezoelectric material mainly composed of ferroelectric lead zirconate titanate (PZT), which is a solid solution of lead titanate and lead zirconate.

  The plurality of individual electrodes 53 are arranged on the upper surface of the upper piezoelectric layer 51 so as to face the plurality of pressure chambers 43, respectively. That is, the plurality of individual electrodes 53 are arranged in the transport direction corresponding to the plurality of nozzles 42 and the plurality of pressure chambers 43, respectively. The common electrode 54 is disposed across the plurality of pressure chambers 43 between the two piezoelectric layers 51 and 52.

  On the upper surface of the piezoelectric layer 51, a plurality of connection terminals 56 are led out from the plurality of individual electrodes 53, respectively. Each connection terminal 56 is drawn from the corresponding individual electrode 53 to a region that does not face the pressure chamber 43 along the longitudinal direction of the pressure chamber 43. Further, the plurality of connection terminals 56 are arranged in the transport direction corresponding to the plurality of individual electrodes 53, and six terminal rows 58y1, 58y2, 58c1, 58c2, 58m1, 58m2 corresponding to the color nozzles 42, Six terminal rows 58k1 to 58k6 corresponding to the black nozzles 42k are formed. More specifically, among the six black terminal rows 58k1 to 58k6, the two right-side terminal rows 58k5 and 58k6 have the terminal rows 58y, 58c and 58m corresponding to the color nozzle 42, and the positions of the connection terminals 56. It's all there. The other black terminal rows 58k1 to 58k4 are shifted to the upstream side in the transport direction with respect to the color terminal rows 58y, 58c, and 58m. As shown in FIGS. 5 to 7, the plurality of connection terminals 56 are each provided with bumps 57 for connecting a COF 60 to be described later.

  As shown in FIGS. 4, 6, and 7, a COF 60 that is a flexible wiring board is disposed above the piezoelectric actuator 31. As shown in FIG. 7, the COF 60 is provided with a driver IC 61 that supplies a drive signal to the piezoelectric actuator 31. The COF 60 is connected to a plurality of connection terminals 56 arranged on the upper surface of the piezoelectric layer 51 via bumps 57 in a state of covering the piezoelectric actuator 31.

  The COF 60 is drawn downstream from the upper surface of the piezoelectric actuator 31 on which the plurality of connection terminals 56 are disposed, and is bent upward. A plurality of reinforcing bumps 62 for reinforcing the connection with the COF 60 are provided on the entire circumference of the edge of the upper surface of the piezoelectric actuator 31.

  The plurality of individual electrodes 53 are connected to the driver IC 61 via connection terminals 56 and wiring (not shown) on the COF 60, and drive signals are respectively supplied from the driver IC 61 to the plurality of individual electrodes 53. The On the other hand, the common electrode 54 is always held at the ground potential by being connected to the ground wiring (not shown) on the COF 60. The portions of the upper piezoelectric layer 51 sandwiched between the individual electrode 53 and the common electrode 54 are each polarized in the thickness direction.

  The operation of the piezoelectric actuator 31 when ejecting ink from the nozzles 42 is as follows. When a drive signal is applied from a driver IC 61 to a certain individual electrode 53, a potential difference is generated between the individual electrode 53 and the common electrode 54 held at the ground potential. As a result, an electric field in the thickness direction is generated in a portion of the piezoelectric layer 51 sandwiched between the individual electrode 53 and the common electrode 54. Further, since the polarization direction of the piezoelectric layer 51 and the direction of the electric field coincide with each other, the piezoelectric layer 51 extends in the thickness direction, which is the polarization direction, and contracts in the plane direction. As the piezoelectric layer 51 contracts and deforms, the portion of the diaphragm 50 that faces the pressure chamber 43 is bent so as to protrude toward the pressure chamber 43. At this time, the volume of the pressure chamber 43 is reduced, pressure is applied to the ink inside the pressure chamber 43, and ink droplets are ejected from the nozzle 42 communicating with the pressure chamber 43.

  As described above, in the inkjet head 4 of the present embodiment, the two nozzle rows 44k5 and 44k6 among the six nozzle rows 44k1 to 44k6 for black and the color nozzle rows 44y, 44c and 44m. The positions of the nozzles 42 in the transport direction are the same. On the other hand, the positions of the nozzles 42 in the transport direction of the other black nozzle rows 44k1 to 44k4 are shifted in the transport direction with respect to the color nozzle rows 44y, 44c, and 44m.

  As shown in FIG. 8, on the downstream side in the transport direction, the nozzles 42 at the ends of the black nozzle row 44k6 and the nozzles 42 at the ends of the color nozzle rows 44y2, 44c2, 44m2 are connected to the other nozzle rows 44. The nozzles 42 are arranged in a state where their positions are aligned downstream of the nozzle 42 at the end in the transport direction. On the other hand, on the upstream side in the transport direction, the nozzle 42 at the end of the black nozzle row 44k1 is disposed so as to protrude further upstream in the transport direction than the nozzle 42 at the end of the other nozzle row 44. Such an arrangement of the nozzles 42 provides the following effects.

(1) In the vicinity of the edge of the inkjet head 4 on the upstream side in the transport direction, the recording paper 100 that has been transported may float or flutter. 1 and 2, the recording paper 100 passing under the ink jet head 4 is suppressed, so that the above-described floating or the like is suppressed to some extent, but it cannot be completely suppressed. .

  In the present embodiment, the positions of the nozzles 42 at the ends of the four nozzle rows 44k6, 44y2, 44c2, and 44m2 are aligned on the downstream side in the transport direction. The nozzle 42 at the end of the black nozzle row 44k1 is disposed so as to protrude from the nozzle 42 at the end of the other nozzle row 44 on the opposite side, upstream in the transport direction. As a result, the number of nozzles 42 arranged closer to the upstream edge of the inkjet head 4 in the transport direction is reduced, so that the recording paper 100 contacts the nozzles 42 when the recording paper 100 floats or varies. It is suppressed as much as possible.

  Further, on the upstream side in the transport direction, the recording paper 100 is likely to float and flutter particularly in the central portion in the scanning direction, which is orthogonal to the transport direction. In this regard, as shown in FIG. 8, the nozzle row 44k1 in which the nozzle 42 at the end is located on the most upstream side in the transport direction is at the end position in the scanning direction among the 12 nozzle rows 44. At the end side in the scanning direction, the recording paper 100 is less likely to float and flutter compared to the central portion. Accordingly, the nozzles 42 located at the end of the nozzle row 44k1 are located closest to the upstream side in the transport direction, but are unlikely to contact the recording paper 100.

(2) As shown in FIG. 4, in this embodiment, the COF 60 is connected to the piezoelectric actuator 31 of the inkjet head 4 so as to cover the piezoelectric actuator 31. The COF 60 connected to the piezoelectric actuator 31 is drawn out from the downstream side in the transport direction, that is, the side where the nozzles 42 at the ends of the four nozzle rows 44k6, 44y2, 44c2, and 44m2 are aligned.

  The piezoelectric actuator 31 has reinforcing bumps 62 on the outer side in the arrangement direction (conveying direction) than the connection terminals 56 located at the ends of each of the 12 terminal rows 58 corresponding to the 12 nozzle rows 44. Is provided. Here, since the COF 60 is easily peeled on the downstream side in the transport direction from which the COF 60 is pulled out, the reinforcing bumps 62 are provided for all the terminal rows 58. On the other hand, on the upstream side in the transport direction, which is the opposite side to the drawing side of the COF 60, the COF 60 is less likely to be peeled as far as the drawing side, so there is no problem even if the reinforcing bumps 62 are omitted for some terminal rows 58.

  Therefore, as shown in FIG. 4, in the present embodiment, the terminal row 58k1 corresponding to the nozzle row 44k1 arranged so that the nozzle 42 at the end protrudes upstream in the carrying direction is only on the downstream side in the carrying direction. Reinforcing bumps 62 are provided, and no reinforcing bumps 62 are provided on the upstream side in the transport direction. Thereby, compared with the case where the reinforcement bumps 62 are provided on both outer sides of all the terminal rows 58, the enlargement of the inkjet head 4 and the COF 60 in the transport direction can be suppressed. Even if the reinforcing bumps 62 of the terminal row 58k1 are omitted, since the reinforcing bumps 62 are provided for the other terminal rows 58, the separation of the COF 60 on the side opposite to the lead-out side can be sufficiently prevented. In FIG. 4, the reinforcing bumps 62 are omitted only for the terminal rows 58k1 corresponding to the black nozzle rows 44k1, but they are also arranged so as to be shifted upstream of the color nozzle rows 44y, 44c, 44m in the transport direction. Also for the terminal row 58k3 corresponding to the nozzle row 44k3, the reinforcing bump 62 on the upstream side in the transport direction may be omitted.

  In the embodiment described above, the ink jet printer 1 corresponds to the liquid ejection apparatus of the present invention. The ink jet head 4 corresponds to the liquid discharge head of the present invention. The transport mechanism 5 corresponds to the transport means of the present invention. The nozzles 42y, 42c, and 42m that discharge the color ink correspond to the first nozzle of the present invention. The nozzle rows 44y1, 44y2, 44c1, 44c2, 44m1, and 44m2 correspond to the first nozzle row of the present invention. The nozzle 42k that discharges black ink corresponds to the second nozzle of the present invention. The nozzle rows 44k1 to 44k6 correspond to the second nozzle row of the present invention. The nozzle rows 44k5 and 44k6 correspond to the same position second nozzle row of the present invention. The nozzle rows 44k1 to 44k4 correspond to the different position second nozzle rows of the present invention. Further, the transport direction corresponds to the first direction of the present invention, and the scanning direction corresponds to the second direction of the present invention.

  The flow path unit 30 corresponds to the flow path structure of the present invention. The piezoelectric actuator 31 corresponds to the discharge driving unit of the present invention. The color connection terminals 56y, 56c, and 56m correspond to the first connection terminal of the present invention. The color terminal rows 58y1, 58y2, 58c1, 58c2, 58m1, and 58m2 correspond to the first terminal row of the present invention. The black connection terminal 56k corresponds to the second connection terminal of the present invention. The black terminal rows 58k1 to 58k6 correspond to the second terminal row of the present invention. The reinforcing bump 62 corresponds to the reinforcing portion of the present invention.

  Next, modified embodiments in which various modifications are made to the embodiment will be described. However, components having the same configuration as in the above embodiment are given the same reference numerals and description thereof is omitted as appropriate.

1] In the above embodiment, there are six color nozzle rows 44y, 44c, 44m and six black nozzle rows 44k, but the number of nozzle rows 44 can be changed as appropriate. Further, two nozzle rows 44k5 and 44k6 of the six black nozzle rows 44k are aligned with the color nozzle rows 44y, 44c and 44m, and the positions of the nozzles 42 are the same. The positions and the number of nozzle rows 44 with the same position can be changed as appropriate.

2] The nozzle guide 16 of FIGS. 1 and 2 may be omitted. In this case, the recording paper 100 is more likely to float or flutter on the upstream side in the transport direction of the inkjet head 4. Therefore, the significance of applying the present invention that can suppress the recording paper 100 from coming into contact with the nozzles 42 is further increased.

3] In the above embodiment, the COF 60 connected to the piezoelectric actuator 31 is disposed so as to cover the piezoelectric actuator 31. On the other hand, if the connection terminals 56 can be centrally arranged at one place on the upper surface of the piezoelectric actuator 31 by, for example, routing wiring from the plurality of individual electrodes 53, the aggregation is possible. The piezoelectric actuator 31 only needs to be connected to the arrangement location. In this case, it is not necessary to arrange the COF 60 so as to cover the piezoelectric actuator 31.

  In the above-described embodiment, the above-described embodiment and the modification thereof are those in which the present invention is applied to an inkjet printer that discharges ink onto a recording sheet and prints an image or the like on the recording sheet. The present invention can also be applied to a liquid ejection apparatus used for various purposes other than printing. For example, the present invention can be applied to a liquid ejection apparatus that forms a conductive pattern on the surface of a substrate by ejecting a plurality of types of liquid onto the substrate.

  Next, disclosed inventions other than the inventions according to claims 1 to 4 described in the claims at the beginning of the application will be described.

A liquid ejection head having a plurality of nozzles arranged along a predetermined first direction;
The liquid discharge heads are arranged at predetermined intervals in the first direction as well as a first nozzle row composed of a plurality of first nozzles arranged at predetermined intervals in the first direction to discharge the first liquid. A plurality of second nozzle rows composed of a plurality of second nozzles for discharging the second liquid,
A plurality of the first nozzle rows for discharging a plurality of types of the first liquid;
The plurality of first nozzle rows and the plurality of second nozzle rows have the same number of nozzle rows,
The plurality of first nozzle rows are arranged side by side in the second direction on one side in a second direction orthogonal to the first direction, and the plurality of second nozzle rows are arranged on the other side in the second direction. A cap member arranged side by side in the second direction and further mounted on the liquid ejection head so as to cover the plurality of nozzles, wherein the cap member covers the plurality of first nozzle rows in common. And a second cap portion that covers the plurality of second nozzle rows in common.
That is, the above disclosed invention corresponds to claim 4 of the scope of claims at the beginning of the application, but does not assume the configuration of claim 1.

  Regarding the above disclosed invention, differences from the above-described embodiment according to the scope of claims of the application will be described with reference to FIG. 2 and FIG. 8 of the above-described embodiment. As in FIG. 2 of the embodiment, the color ink nozzle rows 44y, 44c, and 44m covered with the first cap portion 20a of the cap member 20 and the black ink nozzle row 44k covered with the second cap portion 20b, The number of nozzle rows 44 is equal.

  However, in the above embodiment, as shown in FIG. 8, the four nozzles 42 located at the ends of the four nozzle row groups 45k3, 45y, 45c, 45m are replaced with the nozzles 42 at the ends of the other nozzle row sets 45k1, 45k2. Further, the position in the transport direction is arranged on the downstream side in the transport direction. On the other hand, in the above disclosed invention, the direction in which the positions of the four nozzles 42 located at the ends of the four nozzle row groups 45k3, 45y, 45c, and 45m are not particularly limited. Therefore, the positions of the four nozzles 42 located at the ends of the four nozzle row groups 45k3, 45y, 45c, and 45m may be aligned on the upstream side in the transport direction.

DESCRIPTION OF SYMBOLS 1 Inkjet printer 4 Inkjet head 5 Conveyance mechanism 20 Cap member 20a 1st cap part 20b 2nd cap part 30 Flow path unit 31 Piezoelectric actuator 42 Nozzle 44 Nozzle row 56 Connection terminal 58 Terminal row 60 COF
62 Reinforcing bump 100 Recording paper

Claims (8)

A liquid ejection head having a plurality of nozzles arranged along a predetermined first direction;
Transporting means for transporting, from the one side in the first direction to the other side, the target to which the liquid ejected from the liquid ejecting head lands,
The liquid discharge head is
A first nozzle array comprising a plurality of first nozzles arranged at a predetermined interval in the first direction and discharging a first liquid, and also discharges a second liquid arranged at the predetermined interval in the first direction. A plurality of second nozzle rows composed of a plurality of second nozzles,
The plurality of second nozzle rows include the second nozzle row at the same position where the nozzle positions in the first direction coincide with the first nozzle row, and the nozzle positions in the first direction with respect to the first nozzle row. And the second nozzle row at different positions shifted from each other,
The first nozzle located at the other end of the first nozzle row and the second nozzle located at the other end of the second nozzle row at the same position are the second nozzle row at the different position. At a position on the other side of the first direction than the second nozzle, the position in the first direction is aligned,
The second nozzle located at the one-side end of the second nozzle row at the different position is the first nozzle than the first nozzle of the first nozzle row and the second nozzle of the second nozzle row at the same position. Arranged on the one side of the direction,
The liquid discharge head is disposed on a flow path structure having a liquid flow path including the plurality of nozzles, and on a surface opposite to the liquid discharge surface of the flow path structure, and receives liquid from the plurality of nozzles. A discharge driving unit for discharging,
A flexible wiring board connected to the ejection driving unit of the liquid ejection head;
The ejection driving unit corresponds to a first terminal row including a plurality of first connection terminals arranged in the first direction corresponding to the plurality of first nozzles, and to the plurality of second nozzles, respectively. A second terminal row composed of a plurality of second connection terminals arranged in the first direction,
The flexible wiring board is connected to the first connection terminal and the second connection terminal in a state of covering the discharge driving unit, and is drawn from the discharge driving unit to the other side in the first direction,
For the second terminal row corresponding to the first terminal row and the second nozzle row at the same position, the discharge driving portion and the flexible wiring board are disposed on both outer sides of the terminal row in the first direction. Reinforcing parts to reinforce the joint are provided,
For the second terminal row corresponding to the second nozzle row at the different position, the reinforcing portion is provided only on the other side in the first direction, and the reinforcing portion is not provided on the one side. A liquid ejecting apparatus.   2. The different position second nozzle row is arranged at an end position in a second direction orthogonal to the first direction among all nozzle rows of the liquid ejection head. The liquid discharge apparatus as described. A plurality of first nozzle rows for discharging a plurality of types of the first liquid;
Between the first nozzle rows that discharge the first liquids of different types, the positions of the first nozzles in the first direction are the same,
The plurality of first nozzle rows and the plurality of second nozzle rows have the same number of nozzle rows,
The plurality of first nozzle rows are arranged side by side in the second direction on one side in a second direction orthogonal to the first direction, and the plurality of second nozzle rows are arranged on the other side in the second direction. Arranged side by side in the second direction,
The liquid discharge head further includes a cap member attached to cover the plurality of nozzles,
The cap member has a first cap portion that covers the plurality of first nozzle rows in common, and a second cap portion that covers the plurality of second nozzle rows in common. 3. The liquid ejection device according to 2. A liquid ejection head having a plurality of nozzles arranged along a predetermined first direction;
Transporting means for transporting, from the one side in the first direction to the other side, the target to which the liquid ejected from the liquid ejecting head lands,
The liquid discharge head is
A first nozzle array comprising a plurality of first nozzles arranged at a predetermined interval in the first direction and discharging a first liquid, and also discharges a second liquid arranged at the predetermined interval in the first direction. A plurality of second nozzle rows composed of a plurality of second nozzles,
The plurality of second nozzle rows include the second nozzle row at the same position where the nozzle positions in the first direction coincide with the first nozzle row, and the nozzle positions in the first direction with respect to the first nozzle row. And the second nozzle row at different positions shifted from each other,
The first nozzle located at the other end of the first nozzle row and the second nozzle located at the other end of the second nozzle row at the same position are the second nozzle row at the different position. At a position on the other side of the first direction than the second nozzle, the position in the first direction is aligned,
The second nozzle located at the one-side end of the second nozzle row at the different position is the first nozzle than the first nozzle of the first nozzle row and the second nozzle of the second nozzle row at the same position. Arranged on the one side of the direction,
The liquid ejection head has an ejection drive unit that ejects liquid from each of the plurality of nozzles,
A flexible wiring board connected to the ejection driving unit of the liquid ejection head;
The ejection driving unit corresponds to a first terminal row including a plurality of first connection terminals arranged in the first direction corresponding to the plurality of first nozzles, and to the plurality of second nozzles, respectively. A second terminal row composed of a plurality of second connection terminals arranged in the first direction,
The flexible wiring board is connected to the first connection terminal and the second connection terminal in a state of covering the discharge driving unit, and is drawn from the discharge driving unit to the other side in the first direction,
Reinforcing portions that reinforce the bonding between the ejection driving portion and the flexible wiring board are respectively provided on the other side in the first direction of the first terminal row and the second terminal row. Liquid ejection device. A liquid ejection head having a plurality of nozzles arranged along a predetermined first direction;
Transporting means for transporting, from the one side in the first direction to the other side, the target to which the liquid ejected from the liquid ejecting head lands,
The liquid discharge head is
A first nozzle array comprising a plurality of first nozzles arranged at a predetermined interval in the first direction and discharging a first liquid, and also discharges a second liquid arranged at the predetermined interval in the first direction. A plurality of second nozzle rows composed of a plurality of second nozzles,
The plurality of second nozzle rows include the second nozzle row at the same position where the nozzle positions in the first direction coincide with the first nozzle row, and the nozzle positions in the first direction with respect to the first nozzle row. And the second nozzle row at different positions shifted from each other,
The first nozzle located at the other end of the first nozzle row and the second nozzle located at the other end of the second nozzle row at the same position are the second nozzle row at the different position. At a position on the other side of the first direction than the second nozzle, the position in the first direction is aligned,
The second nozzle located at the one-side end of the second nozzle row at the different position is the first nozzle than the first nozzle of the first nozzle row and the second nozzle of the second nozzle row at the same position. Arranged on the one side of the direction,
The liquid ejection head has an ejection drive unit that ejects liquid from each of the plurality of nozzles,
A wiring board connected to the ejection driving unit of the liquid ejection head;
The ejection driving unit corresponds to a first terminal row including a plurality of first connection terminals arranged in the first direction corresponding to the plurality of first nozzles, and to the plurality of second nozzles, respectively. A second terminal row composed of a plurality of second connection terminals arranged in the first direction,
For the second terminal row corresponding to the second nozzle row at the same position, a reinforcing portion that reinforces the bonding between the ejection driving portion and the wiring board is provided on the one side in the first direction.
The liquid ejecting apparatus, wherein the second terminal row corresponding to the second nozzle row at the different position is not provided with the reinforcing portion on the one side in the first direction. A liquid ejection head having a plurality of nozzles arranged along a predetermined first direction;
Transporting means for transporting, from the one side in the first direction to the other side, the target to which the liquid ejected from the liquid ejecting head lands,
The liquid discharge head is
A first nozzle array comprising a plurality of first nozzles arranged at a predetermined interval in the first direction and discharging a first liquid, and also discharges a second liquid arranged at the predetermined interval in the first direction. A plurality of second nozzle rows composed of a plurality of second nozzles,
The plurality of second nozzle rows include the second nozzle row at the same position where the nozzle positions in the first direction coincide with the first nozzle row, and the nozzle positions in the first direction with respect to the first nozzle row. And the second nozzle row at different positions shifted from each other,
The first nozzle located at the other end of the first nozzle row and the second nozzle located at the other end of the second nozzle row at the same position are the second nozzle row at the different position. At a position on the other side of the first direction than the second nozzle, the position in the first direction is aligned,
The second nozzle located at the one-side end of the second nozzle row at the different position is the first nozzle than the first nozzle of the first nozzle row and the second nozzle of the second nozzle row at the same position. Arranged on the one side of the direction,
A plurality of first nozzle rows for discharging a plurality of types of the first liquid;
The plurality of first nozzle rows and the plurality of second nozzle rows have the same number of nozzle rows,
The plurality of first nozzle rows are arranged side by side in the second direction on one side in a second direction orthogonal to the first direction, and the plurality of second nozzle rows are arranged on the other side in the second direction. Arranged side by side in the second direction,
The liquid discharge head further includes a cap member attached to cover the plurality of nozzles,
The liquid ejecting apparatus according to claim 1, wherein the cap member includes a first cap portion that covers the plurality of first nozzle rows in common and a second cap portion that covers the plurality of second nozzle rows in common. The first nozzle row and the second nozzle row are
The liquid discharge apparatus according to claim 6, wherein the liquid discharge apparatus is formed on the same nozzle plate provided in the liquid discharge head. The liquid ejecting apparatus according to claim 6, wherein the first cap portion and the second cap portion are partitioned by a partition wall portion formed in the cap member.