Nozzle plate, liquid ejecting apparatus, and recording apparatus

Abstract

To reduce the probability of an increase in size.SOLUTION: The nozzle plate has a plurality of nozzle groups each having a plurality of nozzles opened in the ejection surface and arranged in the first direction. The shape formed by the lines connecting the four corners of each nozzle group is a parallelogram. When θ, α, Wx, Wy, Wf, r1, r2, and L2 are defined with respect to the shape, dimensions, and relative position of the arrangement region of the Nb nozzle groups, and A1, A2, A3, A5, C1, and C2 are within predetermined ranges, the following equations are established. (A1-C1sin α) / (sin θ cos α) ≤ r1: (I), A2 / sin (α - θ) ≤ r2: (II), (A3 - r1sin θ) / sin α ≥ r2: (III), (A5 - (Nb-1) - θ) / cos α ≥: (IV), Wx ≥ and Wf> C1 L2 Nbr1cos 2Wy Nbr2 SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a nozzle plate having a plurality of nozzles that eject liquid, a liquid ejection device having the nozzle plate, and a recording device having the liquid ejection device. [Background technology]

[0002] There is known a recording device that records (e.g., prints) by ejecting a liquid (e.g., ink) toward a recording medium (e.g., paper) (see, for example, Patent Document 1 listed below). The liquid is ejected from a nozzle plate having a plurality of nozzles. The plurality of nozzles are arranged, for example, in a matrix. Patent Document 1 discloses a specific example of an arrangement pattern of the plurality of nozzles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2009 / 142894 Summary of the Invention

[0004] A nozzle plate according to one aspect of the present disclosure has an ejection surface extending in a first direction and a second direction orthogonal to each other, and a plurality of nozzle groups each having a plurality of nozzles opening in the ejection surface and aligned in the first direction, wherein, when n is an integer equal to or greater than 2, each of the nozzle groups is configured with n rows of nozzles arranged in parallel to each other, each row having a plurality of nozzles aligned in a direction intersecting the second direction, and the plurality of nozzles are aligned in the second direction as a whole, excluding both end portions in the first direction, at intervals corresponding to a resolution of D [dpi] when viewed in the second direction, one side in the first direction is defined as a first side, the other side is defined as a second side, one side in the second direction is defined as a third side, and the other side is defined as a fourth side, and in each of the nozzle groups, the position of the nozzle located furthest to the first side of the nozzle row located furthest to the third side is defined as a first point, and the position of the nozzle located furthest to the third side is defined as a second point. a second point is a position of the nozzle furthest to the second side in the nozzle row located closest to the fourth side, a third point is a position of the nozzle furthest to the first side in the nozzle row located closest to the fourth side, and a fourth point is a position of the nozzle furthest to the second side in the nozzle row located closest to the fourth side, a shape formed by lines sequentially connecting the first point, the second point, the fourth point, the third point, and the first point is a parallelogram, a first side connecting the first point and the second point is inclined at an angle θ with respect to the first direction so as to be positioned closer to the fourth side as it approaches the second side, the angle θ being greater than 0° and less than 90°, a second side connecting the first point and the third point is inclined at an angle α with respect to the first direction so as to be positioned closer to the fourth side as it approaches the second side, the angle α being greater than the angle θ and less than 90°, and the number of the plurality of nozzle groups is set to N b Let N b The total length of the nozzle groups in the first direction is Wx [mm], and N b the length of the entire nozzle group in the second direction is Wy [mm], the length of the first side is r1 [mm], the length of the second side is r2 [mm], and the distance between the first side and the side opposite to the first side is L2 [mm]; Let C1 = 25.4 / D × n, Let C2 = 2 × C1 / n × (n-1), 2mm≦A1≦10mm, 10mm≦A2≦50mm, 20mm≦A3≦100mm, 50mm≦A5≦300mm, When Wf [mm] is defined as the value obtained by adding C2 to the length from the third point of the nozzle group located closest to the first side to the second point of the nozzle group located closest to the second side, The following formulas (I) to (IV) hold true: (A1-C1sinα) / (sinθcosα)≦r1(I) A2 / sin(α-θ)≦r2(II) (A3-r1sinθ) / sinα≧r2(III) (A5-C1(N b -1)-N b r1cosθ) / cosα≧r2(IV) And Wx≧2Wy and Wf>L2 are satisfied.

[0005] A liquid ejection device according to an aspect of the present disclosure includes a plurality of nozzle plates according to claim 1 arranged in the first direction, and the number of the plurality of nozzle plates is N h year, When 5 inches≦A4≦50 inches, (N h N b r1cosθ+(N h N b -1)C1+C2-A4) / cosα≧r2(V) holds true.

[0006] A recording apparatus according to one aspect of the present disclosure includes the liquid ejection device and a transport device that moves the liquid ejection device and the recording medium relative to each other in the second direction. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic perspective view showing a recording apparatus according to an embodiment. [Figure 2] FIG. 2 is a top view of a plurality of flow path members included in the recording device of FIG. 1. [Figure 3]FIG. 3 is a plan perspective view of one of the flow path members of FIG. 2. [Figure 4] FIG. 4 is an enlarged plan perspective view of region IV in FIG. 3. [Figure 5] 5 is a cross-sectional view taken along line VV in FIG. 4. [Figure 6] FIG. 4 is a schematic diagram showing definitions of symbols used in mathematical expressions relating to nozzle arrangement. [Figure 7] FIG. 10 is a diagram showing an example of values ​​that satisfy a mathematical formula related to the nozzle arrangement. [Figure 8] FIG. 3 is a schematic diagram showing a nozzle arrangement according to a first example. [Figure 9] FIG. 10 corresponds to a part of FIG. 8. [Figure 10] FIG. 10 is a schematic diagram showing a nozzle arrangement according to a second example. [Figure 11] 10 is a table showing parameter values ​​of nozzle arrangements according to third to tenth examples. DETAILED DESCRIPTION OF THE INVENTION

[0008] The drawings used in the following description are schematic. Therefore, for example, certain shapes and / or dimensions may be exaggerated or details may be omitted. Furthermore, the dimensional proportions of the same components in the drawings do not necessarily match. However, this does not deny that shape and / or dimensional features may be extracted from the drawings.

[0009] For convenience, the drawings are illustrated with a Cartesian coordinate system D1D2D3, and terms such as D1 direction, D2 direction, and D3 direction are used. The recording device according to the embodiment may be used in any orientation. However, for convenience, an example in which the +D3 side is upward is used without any particular mention, and expressions based on this example are used.

[0010] (Outline of the embodiment) 1 is a schematic perspective view of a printer 1 (an example of a recording device) according to an embodiment. The printer 1 is configured as an inkjet printer that prints on a medium 101 (an example of a recording medium) such as paper. More specifically, in the illustrated example, the medium 101 is roll paper, and is transported in the direction indicated by the white arrow (or the opposite direction). Then, ink is ejected from an ejection system 3 toward the medium 101, thereby printing.

[0011] The ejection system 3 has, for example, a plurality of (four in the illustrated example) ejection units 5. The plurality of ejection units 5 eject, for example, ink of different colors (for example, four colors). Each ejection unit 5 has, for example, a plurality of (three in the illustrated example) heads 7 arranged in a direction (direction D1) that intersects (for example, is perpendicular to) the transport direction of the medium 101. The ejection system 3, the ejection units 5, and the heads 7 are each an example of a liquid ejection device.

[0012] 2 is a top view showing the portion of one ejection unit 5 on the media 101 side (more specifically, the flow path member 9 described later). In this figure, however, the nozzle area NA located on the lower surface (the surface on the -D3 side) of the flow path member 9 is also shown by a two-dot chain line. The nozzle area NA indicates the area where the nozzles 11 (see FIGS. 4 and 5 described later for the reference numerals) that eject ink are arranged.

[0013] Fig. 3 is a planar perspective view of one flow path member 9. Fig. 4 is an enlarged view of region IV in Fig. 3. However, in Figs. 3 and 4, for convenience of illustration, selected components are shown in perspective. More specifically, Fig. 3 shows, for example, an inlet 15S for supplying ink to the nozzle 11, a main common supply flow path 17S, and a sub-common supply flow path 19S, among the flow paths 13 through which ink flows. Fig. 4 shows, for example, the nozzle 11 in addition to the above components.

[0014] 2, 3, and 4, the plurality of nozzles 11 are arranged in a matrix within a parallelogram-shaped nozzle region NA. The plurality of nozzles 11 included in each nozzle region NA may be collectively referred to as a nozzle group 27. As shown in Fig. 4, in each nozzle group 27, the plurality of nozzles 11 are arranged in a direction intersecting direction D2 (direction D4 in the illustrated example) to form a plurality of nozzle rows 29 (n rows).

[0015] When viewed in the D2 direction (the transport direction of the medium 101), the nozzles 11 of the multiple (n) nozzle rows 29 are positioned in different positions in the D1 direction. In other words, when viewed in the D2 direction, between adjacent nozzles 11 in one nozzle row 29, nozzles 11 in one or more other nozzle rows 29 are positioned. This makes it possible to form dots on the medium 101 that are aligned in the D1 direction at a distance shorter than the distance in the D1 direction between adjacent nozzles 11 in one nozzle row 29. In other words, higher resolution is achieved compared to an embodiment in which only one nozzle row 29 is provided.

[0016] 2, each nozzle region NA has a main region NAm that does not overlap with adjacent nozzle regions NA when viewed in the D2 direction, and sub-regions NAs that do overlap. In the main region NAm, a desired resolution is achieved by only one nozzle region NA (one nozzle group 27). In the sub-region NAs, a desired resolution is achieved by two nozzle regions NA (two sub-regions NAs, two nozzle groups 27) that overlap with each other. From another perspective, by separating the two nozzle regions NA from each other, for example, space that can be used for an appropriate purpose (such as arranging the supply main common channel 17S) is secured between them.

[0017] 6 is a schematic diagram showing the definitions of various symbols used in the description of the embodiment. Generally speaking, the various symbols shown in this diagram correspond to parameters indicating the shape and dimensions of each nozzle group 27 (each nozzle area NA) and the relative positions of the multiple nozzle groups 27. In the embodiment, at least some of the following mathematical expressions using these symbols (and other symbols described below) are satisfied. (A1-C1sinα) / sinθcosα≦r1(I) A2 / sin(α-θ)≦r2(II) (A3-r1sinθ) / sinα≧r2(III) (A5-C1(N b -1)-N b r1cosθ) / cosα≧r2(IV) (N h N b r1cosθ+(N h N b -1)C1+C2-A4) / cosα≧r2(V) Wx≧2Wy (VI) Wf>L2 (VII)

[0018] As will be understood from the following explanation, satisfying formulas (I) to (V) makes it easier to, for example, reduce the size of the nozzle area NA while ensuring the area necessary for arranging certain components. In other words, it becomes easier to satisfy both the demand that is likely to result in an increase in the size of the head 7 (or, from another perspective, the nozzle plate 41N described below) and the opposing demand for a smaller head 7. Furthermore, formulas (VI) and (VII) indicate that, for example, the head 7 is relatively large in the lateral direction with respect to its relative movement with the medium 101.

[0019] It should be noted that technical matters may be extracted from the present disclosure from a different perspective than the above. In this case, the above formulas do not necessarily have to be satisfied.

[0020] The above is an overview of the printer 1 according to the embodiment. The following will provide an overview in the following order. 1. Printer 1 General (Figure 1) 2. Discharge System 3 (Figure 1) 3. Discharge unit 5 (Figs. 1 and 2) 4. Head 7 (Figures 3 to 5) 4.1. Head 7 General 4.2. Flow path member 9 4.2.1. General flow path components 4.2.2. General flow path shape 4.2.3. Common flow path 4.2.4. Individual flow paths Actuators 5. Arrangement of nozzle 11 (Figure 6) 5.1. General nozzle arrangement 5.2. Parameters related to formulas 5.3. Overview of Formulas (I) to (V) 5.4. Derivation process of equation (I) 5.5. Derivation process of equation (II) 5.6. Derivation process of equation (III) 5.7.Derivation process of equation (IV) 5.8.Derivation process of equation (V) 5.9. Specific Value Examples (Figure 7) 5.10. Deviation ratio 5.11. Various Examples of Nozzle Arrangements 5.11.1. First Example 5.11.2. Second Example 5.11.3. Examples 3 to 10 6. Summary of embodiments

[0021] (1. Printers in general) 1 includes, for example, the above-described ejection system 3 and a transport device 31 that transports the medium 101. Although not specifically shown, the printer 1 may also include, for example, a drying device that dries ink that has landed on the medium 101, and a controller that controls each part of the printer 1 (such as the ejection system 3 and the transport device 31).

[0022] The printer 1 prints on, for example, roll paper as the medium 101. However, the medium 101 may also be sheet paper. The size of the medium 101 is also arbitrary. For example, the size of the medium 101 may be small like a receipt, may be a size commonly used in an office, or may be large like a poster. From another perspective, the size of the printer 1 is arbitrary.

[0023] The transport device 31 may have any configuration. FIG. 1 illustrates a configuration in which a roller in contact with the medium 101 is rotated. Other configurations include a configuration in which a belt that adsorbs the medium 101 is transported, and a configuration in which a drum around which the medium 101 is wound is rotated. The transport path for the medium 101 may also be any configuration. For example, the transport path may extend generally straight (including a path that curves gradually so that part or all of it does not make a U-turn) (as in the illustrated example), or it may extend in a U-turn.

[0024] (2. Discharge System) 1 is configured for use in a so-called line printer. That is, the discharge system 3 (or, from another perspective, the discharge unit 5) spans almost the entire width (direction D1) of the medium 101. Then, as the medium 101 is transported, printing is performed in a band-shaped area extending in the direction D1, and a two-dimensional image is formed.

[0025] Unlike the illustrated example, one head 7 may span substantially the entire width of the medium 101. The ejection system 3 may also be for a serial printer. In this case, the operation of printing while moving the head 7 (or the ejection unit 5 or the ejection system 3) in the direction D1 and the transport of the medium 101 are performed alternately. For convenience, in explaining the embodiments, a line printer in which two or more heads 7 (three in FIG. 1) span the width of the medium 101 may be used as an example unless otherwise specified.

[0026] The ejection system 3 has at least one head 7 (12 in the illustrated example). In the example of FIG. 1, as described above, four ejection units 5 are arranged in the D2 direction (the transport direction of the medium 101) corresponding to four colors. In other words, the multiple (three) heads 7 in each ejection unit 5 correspond to ink of the same color. The four colors are, for example, magenta (M), yellow (Y), cyan (C), and black (K). This allows the printer 1 to function as a color printer.

[0027] Unlike the above description, the printer 1 may print in a single color, or conversely, may print in more than four colors. In other words, the number of colors is arbitrary. Also, unlike the above description, two or more ejection units 5 may correspond to one color. This may more than double the resolution of one color. Conversely, one head 7 may correspond to two or more colors. As can be understood from the above, the number of ejection units 5 (heads 7) that the ejection system 3 has is arbitrary.

[0028] The discharge system 3 may hold the discharge unit 5 using an appropriate member. FIG. 1 illustrates a plate-shaped (frame-shaped) unit holding member 33 as an example. The unit holding member 33 has an opening (not shown) that exposes a discharge surface 9a (FIG. 5) of the head 7 where the nozzles 11 are open. The discharge unit 5 (for example, a head holding member 35 described later) abuts against the periphery of the opening of the unit holding member 33 from the +D3 side, and is fixed to the unit holding member 33 by screws (not shown) or the like.

[0029] (3. Discharge unit) Each discharge unit 5 has a plurality of heads 7 (three in the illustrated example) whose positions in the D1 direction are different from each other. The plurality of heads 7 may, for example, have the same configuration as each other, or may have different configurations from each other. In the description of the embodiment, the former mode may be taken as an example unless otherwise specified.

[0030] The number of heads 7 included in the discharge unit 5 is arbitrary. For example, unlike the illustrated example, the number of heads 7 may be two, or may be four or more. Also, unlike the description of the embodiment, only one head 7 may be provided. In other words, the discharge unit 5 may not be conceptualized.

[0031] In each discharge unit 5, the multiple heads 7 are arranged, for example, linearly in the D1 direction (in a row from another perspective). That is, the positions of the multiple heads 7 in the D2 direction are the same. In this regard, the multiple heads 7 may be arranged so that each head has a configuration that is 180° rotationally symmetrical with respect to an axis of symmetry parallel to the D3 axis, or the multiple heads 7 may be arranged so that each head has a configuration that is 180° rotationally asymmetrical with respect to the axis of symmetry parallel to the D3 axis, in the same direction or in opposite directions. Whether the positions in the D2 direction are the same or different may be determined, for example, based on the position of the nozzle 11.

[0032] As shown in FIG. 2, the sub-regions NAs of adjacent heads 7 are adjacent to each other. As with two adjacent sub-regions NAs within one head 7, the desired resolution is achieved by both nozzles 11. In the explanation of the outline of the embodiment, it was stated that the sub-regions NAs contribute to ensuring an area for arranging the main common supply flow channel 17S. In addition to or instead of ensuring such an area, the sub-regions NAs can contribute to ensuring the distance between adjacent heads 7 (however, in the example of FIG. 2, the distance between the two is zero) and / or ensuring the distance from the sub-regions NAs of each head 7 to the outer edge of the head 7 in the portion where the heads 7 are adjacent to each other.

[0033] Unlike the illustrated example, the positions of adjacent heads 7 in the D2 direction may be offset from each other by a distance shorter than the length of the heads 7 in the D2 direction. In other words, in such a positional relationship, the shapes of the sub-regions NAs and the positions of the sub-regions NAs relative to the heads 7 may be set so that the desired resolution is achieved by the adjacent sub-regions NAs of the adjacent heads 7. Furthermore, the multiple heads 7 may be arranged in a staggered pattern. In other words, the multiple heads 7 may be arranged in the D1 direction with their positions in the D2 direction alternately differing, so that the ends of the heads 7 overlap each other when viewed in the D2 direction.

[0034] In each ejection unit 5, the multiple heads 7 may be fixed to one another by an appropriate member. FIG. 1 illustrates a plate-shaped (frame-shaped) head holding member 35. The head holding member 35 has, for example, an opening (not shown) that exposes the ejection surface 9a (FIG. 5) of the head 7 where the nozzles 11 are open. The head 7 abuts against the periphery of the opening of the head holding member 35 from the +D3 side, and is fixed to the head holding member 35 by screws (not shown) or the like. Note that, unlike the illustrated example, the multiple heads 7 may be fixed directly to the unit holding member 33 (the head holding member 35 may not be provided).

[0035] (4. Head) (4.1. Head in general) Any driving method may be used to drive the head 7 to eject ink. For example, the head 7 may be a piezoelectric type that applies pressure to the ink by deforming a piezoelectric element, or a thermal type that applies pressure to the ink by heating the ink to generate bubbles. In the description of the embodiments, the piezoelectric type may be used as an example unless otherwise specified.

[0036] Fig. 5 is a cross-sectional view taken along line VV in Fig. 4. As shown in this figure, the head 7 has, for example, the flow path member 9 described above having nozzles 11, and an actuator substrate 37 that applies pressure to the ink in the flow path member 9 to eject ink droplets. The actuator substrate 37 has a plurality of actuators 39 that correspond to the plurality of nozzles 11, respectively.

[0037] Although not specifically shown, the head 7 may have other components than those described above. For example, although not specifically shown, the head 7 may have the following components: A plate-like or tubular member that supplies (and / or recovers) ink to the flow path member 9. A flexible substrate that inputs a drive signal to the actuator 39. A rigid circuit board that is connected to the flexible substrate. A driver IC (integrated circuit) that generates a drive signal and is mounted on the flexible substrate or circuit board. A housing that houses these components. Regardless of the presence or absence of these components, only the flow path member 9, or only the combination of the flow path member 9 and the actuator substrate 37, may be considered to be the head.

[0038] One head 7 (or, from another perspective, one flow path member 9 or one nozzle plate 41N (described later)) has, for example, multiple (four in the example of FIG. 2) nozzle regions NA (nozzle groups 27). However, one head 7 may only have one nozzle group 27. In other words, the sub-regions NAs may contribute solely to achieving the desired resolution between adjacent heads 7. However, in the description of the embodiments, unless otherwise specified, the description may be made on the premise that one head 7 has multiple nozzle regions NA.

[0039] The head 7 may simply be supplied with ink from a tank (not shown), or may be supplied with ink from a tank (not shown) and collect the ink in the tank. In other words, the ejection system 3 may not circulate ink, or may circulate ink. In the description of the embodiments, a configuration in which ink is circulated will basically be taken as an example.

[0040] (4.2. Flow path components) (4.2.1. General flow path components) The flow path member 9 is a generally flat member. Its planar shape is, for example, a parallelogram, as shown in FIGS. 2 and 3. It should be noted that, in this context, the corners may be chamfered with straight or curved lines, and the sides may have relatively small recesses or protrusions. The same applies to other members and / or shapes. This parallelogram has, for example, a first pair of sides parallel to the D1 direction and a second pair of sides inclined with respect to the D2 direction. The second pair of sides is, for example, along (e.g., parallel to) the side of the sub-region NAs opposite to the main region NAm. From another perspective, the angle of the second pair of sides with respect to the D1 direction is approximately the same as the angle α (FIG. 6) (for example, the difference between the two is 5° or less, 3° or less, or 1° or less).

[0041] Unlike the illustrated example, the shape of the flow path member 9 does not have to be a parallelogram. For example, it is clear that the shape and orientation, etc. of the first opposite side parallel to the D1 direction are arbitrary. It is also clear that the shape and orientation, etc. of the side of the head 7 located at the end that is not adjacent to the other heads 7 are arbitrary. As can be understood from the above explanation that the multiple heads 7 do not have to be arranged in a straight line, the shape and orientation, etc. of the side located between two heads 7 are also arbitrary. A shape for aligning the adjacent sides of two adjacent heads 7 may be formed. Only a portion of the flow path member 9 on the ejection surface 9a side may be parallelogram-shaped.

[0042] The dimensions of the flow path member 9 are arbitrary. Take an example where the printer 1 is a line printer that prints on a relatively wide medium 101. The maximum length of the flow path member 9 in the D1 direction (the length parallel to the D1 direction from the lower left corner to the upper right corner in FIG. 3) may be, for example, 50 mm or more and 300 mm or less. The maximum length of the flow path member 9 in the D2 direction may be, for example, 20 mm or more and 100 mm or less. The maximum length in the D1 direction may be longer than the maximum length in the D2 direction. For example, the former may be 1.5 times or more and 5 times or less than the latter. The thickness of the flow path member 9 may be 0.5 mm or more and 2 mm or less.

[0043] 5, the flow path member 9 is configured, for example, by stacking a plurality of flow path parts 41 in the D3 direction. The flow path parts 41 are generally flat plate-shaped members, and overlapping parts are fixed together with an adhesive (not shown) interposed between them. Holes formed in the plurality of flow path parts 41 are connected to each other to form a flow path 13. The holes that form the flow path 13 are, for example, through-holes that penetrate the flow path part 41 in the thickness direction (D3 direction), or recesses formed on the surface of the flow path part 41 on the +D3 side or the -D3 side.

[0044] Of the multiple flow path parts 41, the one located closest to the -D3 side is formed with a nozzle 11. This flow path part 41 may be referred to as a nozzle plate 41N.

[0045] The shape, dimensions, number of layers, material, etc. of the flow path parts 41 are arbitrary. For example, the shape and size of the outer edge of each flow path part 41 may be the same as the shape and size (as described above) of the outer edge of the flow path member 9. The thickness of the flow path part 41 may be, for example, 10 μm or more and 300 μm or less. The material of the flow path parts 41 may be, for example, metal, resin, or ceramic.

[0046] The flow path member 9 may be realized in a manner different from the illustrated example. For example, all or a part (for example, the part on the +D3 side) of the flow path member 9 (flow path 13) may be configured by stacking flow path parts 41 in a direction perpendicular to the D3 direction, rather than by stacking the flow path parts in the D3 direction. Furthermore, at least a part of the flow path parts may have a shape that cannot be considered as a plate shape.

[0047] The method for forming each of the flow path parts 41, including the nozzle plate 41N, is arbitrary. For example, the holes and outer edges of the flow path part 41 (41N) may be formed by punching, laser processing, dry etching (excluding laser processing), and / or wet etching. In addition, the holes and outer edges of the flow path part 41 (41N) may be formed one after the other, or may be formed simultaneously. In the former case, the methods for forming the holes and outer edges may be the same or different from each other.

[0048] As one example, the nozzles 11 of the nozzle plate 41N may be formed by an appropriate method (e.g., punching) and then the outer edge of the nozzle plate 41N may be formed by a method other than machining (e.g., laser processing). If, instead of this procedure, the nozzles 11 are formed and then the outer edge is formed by cutting the nozzle plate 41N by machining (e.g., punching), distortion may occur near the outer edge of the nozzle plate 41N, which may result in errors in the shape and / or position of the nozzles 11 near the outer edge. The procedure described above can reduce the likelihood of such an error.

[0049] The flow path member 9 may have components other than the flow path, for example, a damper (not shown) that attenuates pressure fluctuations of the ink may be provided.

[0050] (4.2.2. General flow path shape) The flow paths 13 included in the flow path member 9 may have various configurations as long as they have nozzles 11. In the illustrated example, the flow paths 13 are configured to be able to circulate ink. More specifically, for example, the flow paths 13 include a supply flow path that leads from the outside of the flow path member 9 to the nozzles 11, and a recovery flow path that leads from a position in the supply flow path to the outside of the flow path member 9. The supply flow paths, for example, gradually branch off from the outside of the flow path member 9 and reach the multiple nozzles 11. The recovery flow paths, for example, gradually merge from the multiple nozzles 11 side and reach the outside of the flow path member 9. Note that the supply and recovery of ink may be reversed from the following description. That is, ink may be supplied from a flow path that will be described below as a recovery flow path, and ink may be recovered from a flow path that will be described below as a supply flow path.

[0051] More specifically, for example, the supply flow path has the following parts in the order in which the ink flows. Note that some of the individual flow paths 20 described below also constitute recovery flow paths. The number of flow paths is the number in one flow path member 9. Inlet 15S (FIGS. 2 to 4): At least one inlet (four in the illustrated example) is provided to receive ink from the outside of the flow path member 9. · Supply main common flow path 17S (FIGS. 3 and 4): At least one (two in the illustrated example) is provided, extending from the inlet 15S. · Supply sub-common flow path 19S (FIGS. 3 to 5): At least one (in the illustrated example, a plurality (a large number)) is provided, extending (for example, branching) from the supply main common flow path 17S. Individual flow paths 20 (FIGS. 4 and 5): A plurality (a large number in the illustrated example) of these are provided, branching off from the supply sub-common flow path 19S, and each including a nozzle 11.

[0052] The recovery flow path has the following parts in the order in which the ink flows, for example: · Recovery sub-common channel 19C (FIG. 5): At least one (in the illustrated example, a plurality (a large number)) is provided, where a plurality of individual channels 20 join together. · Recovery main common channel 17C (FIGS. 3 and 4): At least one (two in the illustrated example) is provided, extending from the recovery sub-common channel 19C (for example, where a plurality of recovery sub-common channels 19C converge). Outlet 15C (FIGS. 2 to 4): At least one outlet 15C (four in the illustrated example) is provided, to which the main common recovery flow path 17C is connected, and which allows ink to flow out of the flow path member 9.

[0053] As described above, ink is supplied from outside the flow path member 9 to the individual flow paths 20 including the nozzles 11, via the inlet 15S, the supply main common flow path 17S, and the supply sub-common flow path 19S in this order. Ink that has not been ejected from the nozzles 11 is discharged from the individual flow paths 20 to the outside of the flow path member 9, via the recovery sub-common flow path 19C, the recovery main common flow path 17C, and the outlet 15C in this order.

[0054] One inlet 15S, one supply main common flow path 17S, and one supply sub-common flow path 19S are each connected to multiple nozzles 11 (common to multiple nozzles 11). A combination of two or more of these may be considered as one type of common flow path. The same can be said for one outlet 15C, one recovery main common flow path 17C, and one recovery sub-common flow path 19C. Each of the multiple individual flow paths 20 includes a nozzle 11, and basically, the number of the individual flow paths 20 is the same as the number of the nozzles 11.

[0055] (4.2.3. Common flow path) The number of inlets 15S is arbitrary. In the examples of FIGS. 2 to 4, the number of inlets 15S (in one flow path member 9) is four. Unlike the illustrated example, for example, the number of inlets 15S may be one or more and three or less, or five or more. Furthermore, in the illustrated example, as will be understood from the description that follows, the two inlets 15S do not correspond to separate inlets but to two nozzle groups 27 together. Unlike the illustrated example, for example, one inlet 15S may correspond to a nozzle group 27 separately from the other inlet 15S, and / or may correspond to only one nozzle group 27 or to three or more nozzle groups 27.

[0056] The position of the inlet 15S is also arbitrary. In the example of FIGS. 2 to 4, the inlet 15S opens in a region of the upper surface of the flow path member 9 that is outside the nozzle region NA in a planar perspective view. Specifically, the inlet 15S is disposed in a space between the opposite sides of the nozzle region NA that face each other in the direction D2 and that are inclined with respect to the direction D1, and the outer edge of the flow path member 9. This allows the flow path member 9 to be made compact. Furthermore, the inlet 15S is selectively disposed in some of the above-described multiple spaces. Unlike the illustrated example, for example, the inlet 15S may be located outside the above-described spaces, or may be located in all of the above-described spaces.

[0057] The shape and dimensions of the inlet 15S are also arbitrary. In the example of Figures 2 to 4, the inlet 15S has a generally circular cross section, extends in the direction D3, and reaches the upper surface of the supply main common channel 17S. The diameter of the inlet 15S is, for example, generally the same as the width of the supply main common channel 17S.

[0058] The above description of the number, position, shape, dimensions, etc. of the inlet 15S may be applied to the outlet 15C. However, in the illustrated example, the outlet 15C is shifted to the opposite side of the main common supply flow path 17S with respect to the inlet 15S.

[0059] In the illustrated example, the common supply flow paths (17S and 19S) excluding the inlet 15S and the common recovery flow paths (17C and 19C) excluding the outlet 15C are configured to generally overlap in a plan view. That is, as illustrated in FIG. 5, they are arranged one above the other. More specifically, for example, in a plan view, the common recovery flow path is configured by extending the common supply flow path outward from the position of the inlet 15S. The portions (most portions) other than the extended portion are basically the same, except for, for example, manufacturing errors. Therefore, in FIGS. 3 and 4, the shape of the common supply flow path may be considered to indicate the shape (most portions) of the common recovery flow path.

[0060] Unlike the illustrated example, the common supply flow paths (17S and 19S) and the common recovery flow paths (17C and 19C) arranged above and below may have different shapes other than the above-mentioned extension portions. Furthermore, the common supply flow path and the common recovery flow path may be arranged at different positions from each other in a plan view. For example, they may extend partially or entirely parallel to each other in a plan view.

[0061] In the illustrated example, the common supply flow paths (17S and 19S) are located above (on the +D3 side of) the common recovery flow paths (17C and 19C). This allows, for example, the supply sub-common flow path 19S to be closer to the pressure chamber 23 described below, and the recovery sub-common flow path 19C to be closer to the nozzle 11, thereby improving space efficiency. However, the up-down relationship can also be reversed from the illustrated example.

[0062] In the illustrated example, the height (dimension in the D3 direction) of each of the common supply flow paths (17S and 19S) and the common recovery flow paths (17C and 19C) is less than half the thickness (dimension in the D3 direction) of the flow path member 9. However, even in a configuration in which the two overlap, it is possible for one of them to be more than half the thickness of the flow path member 9. Furthermore, in an embodiment in which the two do not overlap, or in an embodiment in which a recovery flow path is not provided, it is clear that the height of the common supply flow path may be more than half the thickness of the flow path member 9 (of course, it may also be less than half). The specific height of each common flow path is arbitrary.

[0063] The number and positions (in plan view) of the supply main common channels 17S are arbitrary. In the example of Fig. 3, one supply main common channel 17S is provided to connect two inlets 15S, and a total of two supply main common channels 17S are provided corresponding to the four inlets 15S. Ink flows from both sides of each supply main common channel 17S toward the center.

[0064] In the illustrated example, each supply main common channel 17S extends between two adjacent nozzle regions NA (nozzle groups 27) roughly along the opposing ends (sides of a parallelogram) of the two nozzle groups 27. Each supply main common channel 17S supplies ink to the two nozzle groups 27 located on both sides thereof via supply sub-common channels 19S.

[0065] Furthermore, in the illustrated example, no supply main common channel 17S is provided in the central region of the three regions located between the four nozzle groups 27. In other words, a supply main common channel 17S is provided in every other region located between the multiple nozzle groups 27. From another perspective, a supply main common channel 17S is provided on only one side of each nozzle group 27 (ink is supplied to each nozzle group 27 from only one side).

[0066] Unlike the illustrated example, for example, one supply main common channel 17S may be provided in one inlet 15S. Then, ink may flow from one end of the supply main common channel 17S to the other. A specific example of such an embodiment is a configuration in which the illustrated supply main common channel 17S is divided into two channels in the length direction. In this case, for example, one supply main common channel 17S supplies ink to half of the +D2 or −D2 sides of the two nozzle groups 27 on both sides.

[0067] Also, unlike the illustrated example, for example, the supply main common flow channel 17S may be provided between the central nozzle groups 27. Furthermore, depending on how the heads 7 are arranged, the supply main common flow channel 17S may be provided on the -D1 side and / or +D1 side of all of the multiple nozzle groups 27 of each head 7. From another perspective, the number of supply main common flow channels 17S may be the same as the number of spaces between the multiple nozzle groups 27, or may be greater than that. Such positions and / or numbers of supply main common flow channels 17S may be applied not only to the illustrated example, but also to an embodiment in which the above-mentioned supply main common flow channel 17S is divided in the length direction.

[0068] In various embodiments different from the illustrated example as described above, each supply main common channel 17S may supply ink only to the nozzle group 27 located on one side thereof, or may supply ink to the nozzle groups 27 located on both sides thereof. From another perspective, one nozzle group 27 may be supplied with ink only from the supply main common channel 17S located on one side thereof, or may be supplied with ink from the supply main common channel 17S located on both sides thereof.

[0069] The shape of the supply main common flow path 17S is also arbitrary. In the illustrated example, the supply main common flow path 17S has a main portion (reference numeral omitted) extending along opposite sides of the nozzle group 27 that face each other in the D1 direction, and a connection portion (reference numeral omitted) extending from the main portion to the inlet 15S. The connection portion extends, for example, along opposite sides of the nozzle group 27 that face each other in the D2 direction. The supply main common flow path 17S (main portion and / or connection portion) extends linearly, for example, with a constant cross section (constant shape and dimensions). The cross-sectional shape is, for example, rectangular.

[0070] The dimensions of the supply main common flow channel 17S are also arbitrary. In a plan view, the inclination angle of the supply main common flow channel 17S (main portion) with respect to the D1 direction may be, for example, approximately the same as the angle α (FIG. 6) (for example, the difference between the two may be 3° or less or 1° or less). The width of the supply main common flow channel 17S (main portion) may be, for example, close to the distance L1 (FIG. 6). For example, the difference between the two may be, using the distance C1 described below, a maximum of 5×C1 or less, 3×C1 or less, or 2×C1 or less. And / or the difference between the two may be a maximum of 0.6×L1 or less, 0.5×L1 or less, or 0.3×L1 or less.

[0071] Each supply sub-common flow path 19S extends, for example, between two adjacent nozzle rows 29 and along (for example, parallel to) those two nozzle rows 29. Each supply sub-common flow path 19S supplies ink to the nozzles 11 included in the two nozzle rows 29 on either side. Therefore, one flow path member 9 has a total of half the number of nozzle rows 29 (24 × 4 ÷ 2 = 48 in the illustrated example). Unlike the illustrated example, for example, one supply sub-common flow path 19S may be provided for one nozzle row 29, or one supply sub-common flow path 19S may be provided for four nozzle rows 29. The shape and dimensions of the supply sub-common flow paths 19S are arbitrary. For example, the supply sub-common flow path 19S extends linearly with a constant cross section (constant shape and dimensions). The cross-sectional shape is, for example, rectangular (see FIG. 5).

[0072] The common supply flow path may be significantly different from the illustrated example. For example, the supply sub-common flow path 19S may extend so as to intersect with the nozzle row 29. More specifically, the supply sub-common flow path 19S may extend along the row of the nozzles 11 arranged in a matrix. Furthermore, for example, the supply main common flow path 17S may be omitted from the flow path member 9, and an inlet 15S may be provided for each supply sub-common flow path 19S. A flow path may be provided that connects the common supply flow path and the common recovery flow path without the individual flow paths 20. For example, a flow path may be provided that connects the end of the supply sub-common flow path 19S opposite to the end connected to the supply main common flow path 17S with the end of the recovery sub-common flow path 19C opposite to the end connected to the recovery main common flow path 17C.

[0073] The above-mentioned explanations regarding the number, position, shape, dimensions, etc. of the common supply flow paths (17S and 19S) may be applied to the common recovery flow paths (17C and 19C) unless there is a contradiction, etc. This applies not only to the case where the common recovery flow path overlaps with the common supply flow path as in the illustrated example, but also to the case where the two do not overlap.

[0074] (4.2.4. Individual flow paths) As shown in Fig. 4, the multiple individual flow paths 20 are arranged, for example, along each supply sub-common flow path 19S. From another perspective, the multiple nozzles 11 are arranged along the supply sub-common flow path 19S. As will be understood from the above explanation, this arrangement constitutes nozzle rows 29 in the illustrated example. Furthermore, in the examples of Figs. 4 and 5, as already mentioned, the multiple nozzles 11 connected to each supply sub-common flow path 19S are arranged in two rows, one row on each side of each supply sub-common flow path 19S. The two individual flow paths 20 leading to the nozzles 11 on both sides are, for example, opposite to each other in the direction intersecting the supply sub-common flow path 19S (direction D2 in the illustrated example).

[0075] 5, each individual flow path 20 has, for example, a supply connection part 21S, a pressure chamber 23, and a descender 25 in that order from the supply sub-common flow path 19S to the nozzle 11. Furthermore, each individual flow path 20 has a recovery connection part 21C that connects the descender 25 and the recovery sub-common flow path 19C. Note that, in FIG. 4, with regard to the individual flow path 20, only the part of the supply connection part 21S that extends from the supply sub-common flow path 19S to the +D3 side, the pressure chamber 23, the descender 25, and the nozzle 11 are shown.

[0076] When the volume of the pressure chamber 23 changes and pressure is applied to the ink, liquid is sent from the pressure chamber 23 to the descender 25, and eventually ink droplets (droplets) are ejected from the nozzle 11. Furthermore, liquid is replenished into the pressure chamber 23 from the supply sub-common channel 19S via the supply connection portion 21S. Ink that is not ejected from the nozzle 11 is recovered into the recovery sub-common channel 19C via the recovery connection portion 21C.

[0077] The shape and dimensions of each part of the individual flow path 20 are arbitrary. In the illustrated example, they are as follows.

[0078] The supply connection portion 21S extends upward from the upper surface of the supply sub-common channel 19S, then extends horizontally, extends upward again, and is connected to one end of the lower surface of the pressure chamber 23. Unlike the example shown in the figure, in an embodiment in which ink is supplied from each supply sub-common channel 19S to two rows of individual channel 20 located on one side thereof, for example, the horizontal lengths of the supply connection portion 21S (and the recovery connection portion 21C) are made different between the individual channel 20 in the two rows.

[0079] The pressure chamber 23 opens, for example, on the upper surface of the flow path member 9 and is closed by the actuator substrate 37. Unlike the illustrated example, the pressure chamber 23 may be closed by a relatively thin flow path part 41. The upper surface of the flow path member 9 may be formed by the upper surface of the flow path part 41, and the actuator substrate 37 may be disposed on that upper surface (however, this may also be considered as a matter of defining the boundary between the flow path member 9 and the actuator substrate 37). The pressure chamber 23 is formed, for example, in a thin shape that spreads with a constant thickness along the upper surface of the flow path member 9. The planar shape of the pressure chamber 23 may be an appropriate shape such as a rhombic shape (example of FIG. 4), a circle, or an ellipse. For example, in a planar perspective view, a portion of the pressure chamber 23 on the supply connection portion 21S side overlaps with the supply sub-common flow path 19S.

[0080] The descender 25 extends from one end of the lower surface of the pressure chamber 23 (the side opposite the supply connection portion 21S) toward the ejection surface 9a. The descender 25 may extend linearly (as in the illustrated example), or may be partially or entirely curved. The descender 25 may extend parallel to the D3 direction (as in the illustrated example), or may be inclined relative to the D3 direction. The shape and dimensions of the cross section of the descender 25 parallel to the D1D2 plane may or may not be constant along the length. The shape of the cross section of the descender 25 parallel to the D1D2 plane is arbitrary, and may be, for example, circular.

[0081] The nozzle 11 opens to a part of the bottom surface of the descender 25 (the surface opposite to the pressure chamber 23). The nozzle 11 may be located, for example, approximately in the center of the bottom surface of the descender 25 (in the illustrated example), or it may not be located in the center. The vertical cross section of the nozzle 11 may be, for example, tapered so that the diameter decreases toward the ejection surface 9a (in the illustrated example), or may be partially or entirely reverse tapered.

[0082] One end of the recovery connection portion 21C opens, for example, in a region closest to the ejection surface 9a on the side surface of the descender 25. The other end opens, for example, to the lower surface of the recovery sub-common channel 19C.

[0083] As described above, the nozzles 11 in different nozzle rows 29 are positioned differently in the direction D1. This arrangement may be achieved by any suitable method. For example, the shapes and dimensions of the individual flow paths 20 may be identical, while the positions of the individual flow paths 20 in the direction along the supply sub-common flow path 19S may be different between nozzle rows 29. Alternatively, for example, the positions and shapes from the supply connection portions 21S to the pressure chambers 23 of the individual flow paths 20 may be identical between nozzle rows 29, while the shapes of the descenders 25 may be different between nozzle rows 29. Alternatively, for example, the method of varying the positions and the method of varying the shapes of the descenders may be combined.

[0084] The configuration of the individual flow paths 20 may be completely different from the illustrated example. For example, depending on the type of actuator 39 (whether it is piezoelectric or not, and the specific structure if it is piezoelectric, etc.), the pressure chamber 23 may be located to the side or below the common flow paths (17S and 19S). Also, for example, the descender 25 may not be provided, and the nozzle 11 may open directly to the bottom surface of the pressure chamber 23. However, the pressure chamber 23 and the descender 25 may be considered as a whole to be the pressure chamber, and even in the illustrated example, the nozzle 11 may be considered to open to the bottom surface of the pressure chamber.

[0085] (4.3. Actuator) The actuator substrate 37 is, for example, substantially plate-shaped and has an area spanning the plurality of pressure chambers 23. Its planar shape may or may not be the same as the planar shape of the flow path member 9. The actuator 39 illustrated in FIG. 5 is configured by a so-called unimorph type piezoelectric actuator. The actuator 39 may also be configured by another type of piezoelectric actuator, such as a bimorph type. The actuator 39 (actuator substrate 37) has, for example, a vibration plate 43, a common electrode 45, a piezoelectric layer 47, and individual electrodes 49, in this order from the flow path member 9 side.

[0086] The vibration plate 43, the common electrode 45, and the piezoelectric layer 47 extend over the plurality of pressure chambers 23 in a plan view, for example. That is, they are provided in common to the plurality of pressure chambers 23. The individual electrode 49 is provided for each pressure chamber 23 at a position facing the pressure chamber 23. The number of individual electrodes 49 is basically the same as the number of pressure chambers 23.

[0087] The portion of the piezoelectric layer 47 sandwiched between the individual electrode 49 and the common electrode 45 is polarized in the thickness direction. Therefore, for example, when an electric field (voltage) is applied in the polarization direction of the piezoelectric layer 47 by the individual electrode 49 and the common electrode 45, the piezoelectric layer 47 contracts in a direction along the layer. This contraction is regulated by the vibration plate 43. As a result, the actuator 39 is flexibly deformed so as to become convex toward the pressure chamber 23. Consequently, the volume of the pressure chamber 23 is reduced, and pressure is applied to the liquid in the pressure chamber 23. Conversely, when an electric field (voltage) is applied in the opposite direction to the polarization direction, the actuator 39 is flexibly deformed so as to become concave relative to the pressure chamber 23. Using this convex and / or concave deformation, the actuator 39 applies pressure to the pressure chamber 23.

[0088] (5. Nozzle Arrangement) (5.1. General nozzle arrangement) The correspondence between the arrangement pattern of the nozzles 11 in the nozzle group 27 (or, from another perspective, the orientation of the parallelogram presented by the nozzle area NA) and the transport direction of the medium 101 is arbitrary. From another perspective, assuming that the Cartesian coordinate system D1D2D3 is defined fixedly with respect to the transport device 31, in the description of the embodiment, the terms -D1 and +D1 may be interchangeable, and / or the terms -D2 and +D2 may be interchangeable. Furthermore, the arrangement pattern of the nozzles 11 in the nozzle group 27 may or may not be 180° rotationally symmetric about an axis of symmetry parallel to the D3 direction.

[0089] For example, it is conceivable to use two flexible substrates to input drive signals to the actuators 39 of one nozzle group 27. If the arrangement of the nozzles 11 is rotationally symmetrical by 180°, then drive signals can be input to the actuators 39 of one nozzle group 27 using two flexible substrates that have the same arrangement of connection points with the actuators 39. Of such two flexible substrates, a first flexible substrate is electrically connected to the actuators 39 that correspond to the nozzles 11 on the -D2 side of a predetermined boundary in one nozzle group 27. A second flexible substrate is electrically connected to the actuators 39 that correspond to the nozzles 11 on the +D2 side of the predetermined boundary in one nozzle group 27.

[0090] As described in the overview of the embodiment, in the main region NAm, a desired resolution is achieved by only one nozzle group 27. Specifically, for example, as shown in FIG. 4, it is assumed that a plurality of nozzles 11 are arranged at regular intervals in each nozzle row 29. The distance of this interval in the direction D1 is C1. Considering a strip-shaped region BA that has a width C1 and extends parallel to the direction D2, in the main region NAm of one nozzle group 27, n nozzles 11 included in different nozzle rows 29 are located in the strip-shaped region BA. This achieves a resolution that allows dots arranged in the direction D1 at intervals of C1 / n on the medium 101.

[0091] Furthermore, as described in the overview of the embodiment, in the sub-region NAs, the desired resolution is achieved by two adjacent nozzle groups 27. Specifically, in the sub-region NAs of each nozzle group 27, for example, less than n nozzles 11 included in different nozzle rows 29 are located in the band-shaped region BA. However, in two sub-regions NAs where the positions in the D1 direction of two adjacent nozzle groups 27 overlap, a total of n nozzles 11 are located in the band-shaped region BA. Furthermore, the positions of the n nozzles 11 in the D1 direction are different from each other. This achieves a resolution of C1 / n.

[0092] In each nozzle group 27, the positions of the multiple nozzle rows 29 in the D1 direction are shifted by a distance C1 or more so that, for example, the nozzles on the +D2 side are positioned closer to the +D1 side. This ensures that the number of nozzles 11 (or, from another perspective, nozzle rows 29) included in the strip-shaped area BA in each sub-area NAs is less than n. Furthermore, the inclination angle of the -D1 side of the sub-area NAs located on the -D1 side of the main area NAm, or the +D1 side of the sub-area NAs located on the +D1 side of the main area NAm, is adjusted, for example, by determining the number of strip-shaped areas BA to be shifted for each row, or the number of rows to be shifted for each strip-shaped area BA. The amount of shift does not have to be constant across the entire side.

[0093] In each strip area BA, the relationship between the row number (described below) to which each nozzle 11 belongs and the relative position in the D1 direction with respect to other nozzles 11 (i.e., the arrangement pattern of nozzles 11 within the strip area BA) is arbitrary. For example, in each strip area BA, the n nozzles 11 may or may not be arranged so that the nozzles on the +D2 side are located closer to the +D1 side.

[0094] In the above description, the nozzles 11 in each nozzle row 29 are arranged at regular intervals. From another perspective, the arrangement pattern of the n nozzles 11 within a strip area BA is the same across multiple strip areas BA. However, the arrangement pattern does not have to be regular. Alternatively, an integer multiple of n nozzles 11 may be arranged in a regular pattern, and the pattern may be repeated.

[0095] As described above, the interval C1 between adjacent nozzles 11 is constant in each nozzle row 29. Furthermore, when the nozzles 11 in n nozzle rows 29 are projected in the D2 direction, the pitch (C1 / n) of the projection points aligned in the D1 direction is constant. Furthermore, in each nozzle row 29, the multiple nozzles 11 are arranged linearly.

[0096] The nozzles 11 may be intentionally positioned slightly offset from their original positions so long as the principle of achieving a resolution of C1 / n is not violated. For example, in a configuration in which the spacing C1 between adjacent nozzles 11 in each nozzle row 29 is intended to be constant, the spacing C1 may be varied by a small amount. Also, in a configuration in which multiple nozzles 11 in each nozzle row 29 are intended to be arranged linearly, the nozzles 11 may be arranged in a slight meandering pattern. Such variations (e.g., randomness) contribute to, for example, reducing the likelihood of periodic occurrence of irregularities and reducing the visibility of the irregularities.

[0097] Because the above-described variations are relatively small, they may be considered to be equivalent to tolerances when determining whether the various mathematical formulas in the present disclosure are satisfied. For example, even if the value of a specific parameter deviates from the range derived from the mathematical formula by an amount equivalent to the above-described variations, the mathematical formula may be determined to be satisfied. Of course, unintended deviations due to manufacturing errors may also exist.

[0098] If the number of rows n of the nozzle rows 29 is too small, it may be possible to simply arrange the nozzles 11, but when arranging structures such as the pressure chambers 23, the following problem may occur, depending on other design parameters. When the number of rows n is small, it may be necessary to increase the angle θ of the nozzle rows 29 (approaching 90°) to achieve a predetermined resolution. If the angle θ is large, lengthening the nozzle rows 29 increases the size of the head 7 in the D2 direction, so it is considered that the nozzle rows 29 cannot be made too long. If the angle θ is large and the nozzle rows 29 are not very long, the size of the nozzle groups 27 in the D1 direction decreases. This increases the number of nozzle groups 27 per unit length. The boundaries between the nozzle groups 27 may result in slightly reduced printing accuracy. Furthermore, for example, structures such as the inlet 15S may increase in number in accordance with the number of nozzle groups 27, and the area in which such structures are arranged also increases. If the number n of nozzle rows 29 is set to 12 or more, preferably 16 or more, and especially 20 or more, the size of the head 7 in the D2 direction can be reduced, and the number of nozzle groups 27 per unit length can also be reduced.

[0099] In the process of deriving a formula, various assumptions may be made, which do not necessarily hold true when the final formula is applied to a product.

[0100] (5.2. Parameters related to formulas) Before explaining formulas (I) to (V), we will explain the parameters (symbols) used in these formulas. For convenience of explanation, as shown in Fig. 6, we will use the x-axis corresponding to the D1 axis and the y-axis corresponding to the D2 axis.

[0101] In the following description, it is assumed that the multiple nozzle groups 27 have the same configuration regarding the arrangement of the nozzles 11. It is also assumed that the multiple nozzle groups 27 are linearly arranged in the x direction at regular intervals. If these assumptions do not hold, for example, the value of a parameter used in the formula may be specified in a direction that makes it difficult to satisfy the formula, and it may be determined whether the formula is satisfied. For example, if the multiple nozzle groups 27 are not linearly arranged and therefore the length of the multiple nozzle groups 27 in the y direction (Wy, described below) is large, the larger value of Wy may be used in a formula that requires Wy to be small. The same applies to the assumptions for each nozzle group 27 (for example, those described below).

[0102] The number of rows in the multiple nozzle rows 29 is n. The number of nozzles 11 included in the multiple nozzle rows 29 is m, which is the same for each nozzle row. The n nozzle rows 29 are counted from the -y side (an example of the third side) as the first row, second row, third row, ..., nth row. In any nozzle group 27 except for the nozzle group 27 furthest from the +x side, the nozzles 11 included in each nozzle row 29 may be counted from the -x side as the first column, second column, third column, ..., mth column. In each nozzle row 29 of the nozzle group 27 located adjacent to any of the nozzle groups 27 on the +x side, the nozzle 11 furthest from the -x side may be referred to as the nozzle 11 in the (m+1)th column. Note that, although the term "column" is used for convenience, nozzles 11 with the same column number in different nozzle rows 29 do not necessarily form a column (are included in the same band-shaped area BA).

[0103] The position of nozzle 11 is expressed as coordinates (x (行,列) ,y (行,列) ) in Figure 6. (1,1) ,y (1,1) ), (x (1,m) ,y (1,m) ), (x (n,1) ,y (n,1) ) and (x (1,m+1) ,y (1,m+1) The coordinates of four points (x) of the nozzle group 27 (or any nozzle group 27) on the -x side are shown as examples. (1,1) ,y (1,1)) is sometimes used as the origin in the Cartesian coordinate system xy. In Figure 6, for convenience, (x (1,1) ,y (1,1) ) and the symbols for the Cartesian coordinate system xy are shown at a position away from the center.

[0104] The corners and sides of each nozzle area NA will be referred to as follows. First point P1: The position of the nozzle 11 located furthest on the -x side (an example of the first side) of the nozzle row 29 located furthest on the -y side (an example of the third side). Second point P2: The position of the nozzle 11 located furthest on the +x side (an example of the second side) of the nozzle row 29 located furthest on the -y side. Third point P3: The position of the nozzle 11 located furthest on the −x side of the nozzle row 29 located furthest on the +y side (an example of the fourth side). Fourth point P4: Position of the nozzle 11 located furthest on the +x side in the nozzle row 29 located furthest on the +y side. ·First side S1: The side connecting the first point P1 and the second point P2. · Second side S2: The side connecting the first point P1 and the third point P3. ·Third side S3: The side connecting the second point P2 and the fourth point P4. ·Fourth side S4: The side connecting the third point P3 and the fourth point P4.

[0105] The symbols shown in FIG. 6 have the following meanings: ·θ: Inclination angle of the first side S1 with respect to the x-axis. α: Inclination angle of the second side S2 with respect to the x-axis. ·r1[mm]: Length of the first side S1. ·r2 [mm]: Length of the second side S2. L1 [mm]: The distance (shortest distance) between adjacent nozzle groups 27. L2 [mm]: The distance between the first side S1 and the fourth side S4 (shortest distance). ·Wx [mm]: the overall length of the multiple nozzle groups 27 in the x direction. Wy [mm]: the overall length of the nozzle groups 27 in the y direction. Wf [mm]: the length in the x direction of the range of all the nozzle groups 27 within which the desired resolution is achieved.

[0106] θ and α are each greater than 0° and less than 90°. In other words, the positive and negative sides of the x-axis and y-axis are defined so that θ and α fall within the above-mentioned angle ranges. Based on the definitions of θ and α, the following relationship holds: 0°<θ<α<90° (1)

[0107] As can be understood from the definitions of the first side S1 and the second side S2, θ, α, r1, and r2 may be determined based on the position of the nozzle 11. L1, L2, Wx, Wy, and Wf may also be determined based on the position of the nozzle 11. However, in the process of deriving the formulas, for convenience, differences in position in the D1 direction (up to about C1) due to nozzle rows 29 within the band-shaped area BA may be ignored.

[0108] More specifically, distance L1 may be the distance between the third side S3 of the nozzle group 27 on the -x side and the second side S2 of the nozzle group 27 on the +x side of two adjacent nozzle groups 27. The two sides are basically parallel, and the shortest distance between them is the distance in a direction perpendicular to them. Regarding distance L2, the first side S1 and the fourth side S4 are basically parallel, and the shortest distance between them is the distance in a direction perpendicular to them.

[0109] Distance Wx is usually the same as or close to the distance in the x direction between first point P1 of nozzle group 27 closest to the -x side and fourth point P4 of nozzle group 27 closest to the +x side in one head 7. When multiple nozzle groups 27 in one head 7 have the same configuration and are arranged in a linear fashion, distance Wy is usually the same as or close to the distance in the y direction between first point P1 and fourth point P4 of any nozzle group 27.

[0110] Distance Wf can be considered to be the length in the x direction of the range in which multiple nozzles 11 are arranged at C1 / n when viewed in the y direction in one head 7. In other words, it can be considered to be the length obtained by excluding the x direction lengths of the sub-regions NAs located at both ends of the multiple nozzle regions NA as a whole from the x direction length of the multiple nozzle regions NA as a whole in one head 7. Distance Wf is usually calculated by adding C2 to the distance in the x direction between the third point P3 of the nozzle group 27 furthest on the -x side and the second point P2 of the nozzle group 27 furthest on the +x side in one head 7.

[0111] C2 will now be explained. Consider the range on the -x side from the third point P3 of the nozzle group 27 furthest to the -x side of one head 7, in which the nozzles 11 are arranged at the desired resolution. The n-1 nozzles 11 on the -x side from the third point P3 are the nozzles 11 included in the nozzle group 27. These n-1 nozzles 11 include one nozzle 11 each from the 1st to n-1th nozzle rows, so printing at the desired resolution is possible. In the nozzle group 27, it is the nozzle 11 corresponding to the nth nozzle 11 that cannot print at the desired resolution on the -x side from the third point P3. This position is a position where, if another head 7 is arranged on the −x side, printing will be performed from the nozzles 11 of the other head 7, and printing cannot be performed by the nozzle group 27 in question.

[0112] Therefore, the range in which nozzles 11 are arranged at the desired resolution on the -x side from third point P3 of nozzle group 27 furthest on the -x side of one head 7 is C1 / n × (n-1). The same is true on the +x side, so the range in which one head 7 can print at the desired resolution is obtained by adding double this value C2 to the distance in the x direction between third point P3 of nozzle group 27 furthest on the -x side and second point P2 of nozzle group 27 furthest on the +x side.

[0113] The following symbols shown in Figure 2 may also be used: We [mm]: the length in the x direction of the range in which the desired resolution is achieved in one discharge unit 5. For ease of illustration, FIG. 2 shows only both sides of the dimension line for the distance We. The above explanation of the distance Wf may be applied to the distance We by substituting the term "head 7" with the term "ejection unit 5." That is, like the distance Wf, the distance We is the distance in the x direction between the third point P3 of the nozzle group 27 on the -x-most side of the head 7 on the -x-most side and the second point P2 of the nozzle group 27 on the +x-most side of the head 7 on the +x-most side, plus C2. Note that FIG. 2 is not drawn in a way that allows the influence of C2 to be discerned.

[0114] The following symbols shown in Figure 3 may also be used: ·W mani [mm]: Width of supply sub-common channel 19S ·W g [mm]: Width between adjacent supply sub-common channels 19S

[0115] Although not shown, the following parameters may also be used: N h : The number of heads 7 in one discharge unit 5. N b : The number of nozzle groups 27 in one head 7. N mani : The number of supply sub-common flow paths 19S associated with one nozzle group 27. ·D[dpi]: Resolution achieved by head 7. In the above description, the term "head 7" may be replaced with the term "nozzle plate 41N." h is 3 and N b is 4 and N mani is 12. D can be expressed as 25.4 / C1×n using C1 [mm].

[0116] (5.3. Overview of Equations (I) to (V)) As will be described in detail later, the formula (I) is derived so that the distance L1 satisfies the following condition. A1≦L1 (2) The distance A1 is a length required from the viewpoint of, for example, ensuring the width of the main common supply channel 17S and / or ensuring the distance between adjacent heads 7. The specific value thereof is arbitrary.

[0117] As will be described in detail later, the formula (II) is derived so that the distance L2 satisfies the following condition. A2≦L2 (3) The distance A2 is a length required from the viewpoint of, for example, ensuring an area for arranging the individual flow paths 20 and the supply sub-common flow path 19S, etc. The specific value thereof is arbitrary.

[0118] As will be described in detail later, the formula (III) is derived so that the length Wy satisfies the following condition. A3≧Wy (4) The length A3 is, for example, a length required from the viewpoint of miniaturization in the y direction of the head 7. The specific value thereof is arbitrary.

[0119] As will be described in detail later, formula (IV) is derived so that the length Wx satisfies the following condition: A5≧Wx (40) The length A5 is, for example, a length required from the viewpoint of miniaturization in the x direction of the head 7. The specific value thereof is arbitrary.

[0120] As will be explained in detail later, equation (V) is derived so that the length We satisfies the following condition: A4≦We (5) The length A4 is, for example, a length required in terms of the width in the x direction that can be printed by the discharge unit 5. The specific value thereof is arbitrary.

[0121] If formulas (2) and (3) (and formula (5)) are to be satisfied, there is a high probability that the head 7 (or the ejection unit 5) will become larger. On the other hand, if formulas (4) and (40) are to be satisfied, there is a high probability that the head 7 will become smaller. Therefore, by satisfying formulas (I) to (IV) (and formula (V)), it is possible to balance various requirements.

[0122] (5.4. Derivation process of equation (I)) As described above, formula (I) is based on formula (2). The distance L1 in formula (2) can be calculated based on r1, θ, α, etc., for example, as follows:

[0123] In any nozzle group 27 except for the nozzle group 27 closest to the +x side, the second side S2 (sometimes referred to as the "first straight line") can be expressed by the following formula. y=tan(α)x (6) In any of the nozzle groups 27 described above, the third side S3 (sometimes referred to as the "second straight line") can be expressed by the following formula. y=tan(α)x+b2(7) In the nozzle group 27 adjacent to any of the nozzle groups 27 from the +x side, the second side S2 (sometimes referred to as the "third straight line") can be expressed by the following formula. y=tan(α)x+b3(8) In this case, the distance L1 can be calculated using the following formula. L1=(b2-b3)×cos(α) (9) Therefore, b2 and b3 are calculated.

[0124] The second and third lines are the parallel translations of the first line. Therefore, the coordinates (x (行,列) ,y (行,列) ), the second and third lines can be expressed as follows: yy (1,m) =tan(α)(xx (1,m) ) (10) yy (1,m+1) =tan(α)(xx (1,m+1) ) (11) By rearranging the above equation, the following equation is obtained. y=tan(α)x-tan(α)x (1,m) +y (1,m) (12) y=tan(α)x-tan(α)x (1,m+1) +y (1,m+1) (13) The second and third terms on the right side of equation (12) correspond to b2. The second and third terms on the right side of equation (13) correspond to b3.

[0125] Δb is defined as follows: Δb = b2 - b3 (14) Then, the following equation is obtained from equations (12) and (13). Δb=(-tan(α)x (1,m) +y (1,m) ) -(-tan(α)x (1,m+1) +y (1,m+1) ) (15) The above formula can be rearranged as follows: Δb=tan(α)(x (1,m+1) -x (1,m) )+y (1,m) -y (1,m+1) (16)

[0126] As described above, in the Cartesian coordinate system xy, the position of the nozzle 11 in the first row and the first column is set as the origin. Therefore, the following equation holds for the third term on the right side of equation (16). y (1,m+1) =0 (17) When the adjacent nozzle groups 27 are viewed in the y direction, the distance between the nozzle 11 in the m-th column of the first row and the nozzle 11 in the m+1-th column of the first row (i.e., x (1,m+1) -x (1,m) ) is C1 [mm]. Therefore, if the resolution is D [dpi], the following equation holds for part of the first term on the right side of equation (16): x (1,m+1) -x (1,m) =25.4 / D×n=C1 (18) Therefore, equation (16) becomes as follows: Δb=C1tan(α)+y (1,m) (19)

[0127] Regarding the second term on the right side of equation (19), the following equation holds. y (1,m) =r1sinθ (20) Therefore, when equations (19) and (20) are substituted into equation (9), the following equation is obtained. L1=cosα(C1tan(α)+r1sinθ) (21) From the above equation, a formula for determining the distance L1 based on r1, θ, α, etc. is obtained.

[0128] Then, by substituting equation (21) into equation (2), the following equation is obtained. A1≦cosα(C1tan(α)+r1sinθ) (22) By rearranging this, the following formula is obtained. (A1-C1sinα) / (sinθcosα)≦r1(23) Equation (23) is the same as equation (I) already mentioned.

[0129] (5.5. Formula (II)) As already mentioned, the formula (II) is based on the formula (3). As can be seen from FIG. L2=r2sin(α-θ) (24) Substituting equation (24) into equation (3) gives the following equation: A2≦r2sin(α−θ) (25) Here, the following holds from the definitions of α and θ. 0 <sin(α-θ)<1 (26) Therefore, by rearranging equation (25), the following equation is obtained. A2 / sin(α-θ)≦r2(27) Equation (27) is the same as equation (II) already mentioned.

[0130] The distance A2 is the number N of the supply sub-common flow paths 19S located in one nozzle area NA. mani , the width W of the supply sub-common flow path 19S mani , and the width W between adjacent supply sub-common flow paths 19S g For example, the distance A2 may be calculated by the following formula: A2=N mani W mani +(Nmani -1)W g (46)

[0131] (5.6.Equation (III)) As mentioned above, the formula (III) is based on the formula (4). The length Wy in the formula (4) is calculated by dividing the origin of the x and y coordinates by (x (1,1) ,y (1,1) ) and the nozzle area NA is a parallelogram, it can be expressed by the following formula. Wy=y (n,m) =y (1,m) +y (n,1) (28) The first and second terms in the rightmost equation above are expressed by the following equations, respectively. y (1,m) =r1sinθ (29) y (n,1) =r2sinα (30) Substituting equations (28) to (30) into equation (4), the following equation is obtained. A3≧r1sinθ+r2sinα (31) By rearranging the above equation, the following equation is obtained. (A3-r1sinθ) / sinα≧r2(32) Equation (32) is the same as equation (III) already mentioned.

[0132] (5.7.Equation (IV)) As already mentioned, the formula (IV) is based on the formula (40). As can be seen from FIG. 6, the length Wx in the formula (40) is expressed by the following formula. Wx=N b r1cosθ+r2cosα+(N b -1)C1 (41) Substituting equation (41) into equation (40) gives the following equation: A5≧N b r1cosθ+r2cosα+(N b -1)C1 (42) By rearranging the above equation, the following equation is obtained. (A5-C1(N b -1)-N br1cosθ) / cosα≧r2(43) Equation (43) is the same as equation (IV) already mentioned.

[0133] (5.8.Equation (V)) As mentioned above, formula (V) is based on formula (5). Here, it is assumed that in one discharge unit 5, the nozzles 11 are arranged from the first row to the k-th row, from the nozzle group 27 located furthest on the -x side to the nozzle group 27 located furthest on the +x side. That is, in one discharge unit 5, the x coordinate of the third point of the nozzle group 27 located furthest on the -x side is x (n,1) In addition, in one discharge unit 5, the x coordinate of the second point of the nozzle group 27 located closest to the +x side is x (1,k) is.

[0134] When defined as above, the length We in equation (5) is roughly x (1,k) -x (n,1) Here, the coordinate x is expressed by ignoring the difference in the x-direction position in the band-shaped area BA due to the nozzle row 29. That is, x (1,k) -x (n,1) evaluates the length of the band-shaped area BA at both ends of one discharge unit 5 as short. Therefore, the formula that more accurately expresses the length We is as follows: We=x (1,k) -x (n,1) +2×C1 / n×(n-1) (33)

[0135] The first term on the right side of equation (33) can be expressed as follows: x (1,k) =N h N b r1cosθ+(N h N b -1)C1 (34) The second term on the right side of equation (33) can be expressed as follows: x (n,1) =r2cosα (35) The third term on the right side of equation (33) is expressed as follows: C2=2×C1 / n×(n-1) (36) Substituting these equations into equation (33), we obtain the following equation: We=N h N b r1cosθ+(N h N b -1)C1-r2cosα+C2 (37)

[0136] Substituting equation (37) into equation (5) gives the following equation: A4≦N h N b r1cosθ+(N h N b -1)C1-r2cosα+C2 (38) By rearranging the above equation, the following equation is obtained. r2≦(N h N b r1cosθ+(N h N b -1)C1+C2-A4) / cosα (39) Equation (39) is the same as equation (V) already mentioned.

[0137] (5.9. Examples of specific values) FIG. 7 is a diagram showing examples of values ​​that satisfy formulas (I) to (V). In this diagram, the horizontal axis represents α°, and the vertical axis represents r2 [mm]. The ranges that satisfy each of formulas (I) to (V) are the ranges extending from the lines labeled (I) to (V) in the diagram in the direction of the arrows. The hatched design range DW is the range that satisfies all of formulas (I) to (V).

[0138] Equations (II) to (V) all contain α as a variable. Furthermore, Equations (II) to (V) all contain r2 as a variable. Therefore, the values ​​of the other variables are fixed to predetermined values, and the range of values ​​that r2 can take when the values ​​of α in Equations (II) to (V) are changed is calculated and shown in Figure 7. Since Equation (I) contains α but does not contain r2, the range of values ​​that α can take when the values ​​of the other variables are fixed to predetermined values ​​as described above is shown by a line parallel to the vertical axis.

[0139] Since formulas (I) to (V) differ from each other in defining the upper and lower limits of r1 or r2, the values ​​of the variables that satisfy these formulas are limited. Here, an example is shown in which the design range DW is formed, but depending on the values ​​of the variables, the lower limit defined by one formula may be larger than the upper limit defined by another formula, and the design range DW may not be established.

[0140] As an example of a range of values ​​that can be established as the design range DW, the range including the values ​​used in the calculation of FIG. 7 is shown below. D: 600dpi or more and 2400dpi or less n: 12 or more and 48 or less m: 30 or more and 120 or less N h : 2 or more and 6 or less N b : 2 or more and 8 or less C1: 0.2mm to 1.0mm C2: 0.5mm to 2.0mm r1: 15mm or more and 60mm or less r2: 20mm or more and 80mm or less θ: 10° to 40° (θ<α) α: 30° or more and less than 90° A1: 2mm to 10mm A2: 10mm or more and 50mm or less A3: 20mm or more and 100mm or less A4: 5inch or more and 50inch or less A5: 50mm or more and 300mm or less N mani : 6 or more and 24 or less W mani : 0.5mm to 3.0mm W g : 0.3mm or more and 1.5mm or less L1: 2mm to 10mm (however, L1≧A1) L2: 10mm or more and 50mm or less (however, L2≧A2) Wy: 20mm to 100mm (Wy≦A3) Width: 5 inches or more and 50 inches or less (Weight ≥ A4) Wx: 50mm to 300mm (Wx≦A5)

[0141] (5.10. Deviation ratio) The parameter f that defines the arrangement of the nozzles 11 will be described below.

[0142] Consider how much the third point P3 is shifted toward the +D1 side relative to the first point P1 in one nozzle group 27. The shift g is a natural number with the distance C1 as a unit and with decimals rounded down. In other words, the shift g is the integer part of the value obtained by dividing the distance parallel to the D1 direction from the first point P1 to the third point P3 by the distance C1.

[0143] The ratio f (= g / n) of the offset g to the number n of nozzle rows 29 is a parameter related to the angle α. As f becomes smaller, the angle α becomes larger (approaching 90°), and as f becomes larger, the angle α becomes smaller (approaching 0°).

[0144] Reducing f increases the ratio of the printing width that can be printed at a specified resolution to the size of the head 7 in the D1 direction, but reducing f also narrows the spacing between the nozzle groups 27. For this reason, f may be set to 1.1 or greater and 1.5 or less (when n=24, g is 27 or greater and 36 or less), or even 1.15 or greater and 1.45 or less (when n=24, g is 28 or greater and 34 or less).

[0145] (5.11. Various Examples of Nozzle Arrangements) Various specific examples of the arrangement of the nozzles 11 are shown below.

[0146] (5.11.1. Example 1) FIG. 8 shows the arrangement of nozzles 11 according to the first example. Specifically, this figure schematically shows the arrangement of nozzles 11 in the adjacent portions of two nozzle groups 27. Black circles in the figure represent nozzles 11. The vertical lines are parallel to the D2 direction and aligned in the D1 direction at a fixed interval C1. In other words, the area between the vertical lines represents a band-shaped area BA. However, the vertical lines are drawn so as to pass through the nozzles 11 in the nozzle row 29 closest to the -D2 side. Note that the aspect ratio of the figure does not necessarily match the actual one. In this example, the number of rows n is 24.

[0147] FIG. 9 is a diagram showing a portion of FIG. 8. Specifically, FIG. 9 is a diagram showing the arrangement (periodic pattern) of the nozzles 11 belonging to each strip-shaped area BA of the main area NAm. The numbers on the vertical axis indicate the nozzle row 29 numbers. For example, "1" on the vertical axis indicates the first row. As mentioned above, the relationship between the row number to which each nozzle 11 belongs and its relative position in the D1 direction with respect to other nozzles 11 is arbitrary. In the illustrated example, the nozzles 11 are arranged such that a line meanders in order from the nozzles 11 in the first row, the nozzles 11 in the second row, the nozzles 11 in the third row, ..., and the nozzles 11 in the nth row.

[0148] (5.11.2. Example 2) Fig. 10 is a diagram showing the arrangement of nozzles 11 according to a second example, and is a diagram similar to Fig. 8. In the second example, like the first example, the number of rows n is 24. However, the periodic pattern of the nozzles 11 and the specific offset method of the nozzles 11 at the left and right ends of the nozzle group 27 are different from those in the first example.

[0149] (5.11.3. Examples 3 to 10) Prior to explaining the arrangements of Examples 3 to 10, a supplementary explanation of Example 1 will be provided. Fig. 9 shows the periodic pattern of the nozzles 11. Fig. 9 shows in which nozzle row 29 the nozzles 11 are arranged, in order in the D1 direction. The periodic pattern is one period of the arrangement of the nozzles 11, which is repeated periodically.

[0150] Here, let us consider the distance between the nozzles 11. The nozzles 11 are arranged with a certain distance between them so as not to be subject to restrictions when manufacturing the nozzle plate 41N. Furthermore, there are restrictions when manufacturing the flow path parts 41 for the descenders 25 and pressure chambers 23 connected to the nozzles 11, so the nozzles 11 are arranged with a certain distance between them so that a certain distance can be maintained between them. Even for nozzle groups 27 with the same angle α or offset g, the distance between the nozzles 11 changes depending on the periodic pattern. Conversely, for nozzle groups 27 with different angles α or offset g, the periodic patterns that can increase the distance between the nozzles 11 may differ.

[0151] 11 shows periodic patterns and the like for multiple examples (Examples 3 to 10) in which the combination of the offset g and the periodic pattern is different from one another. The table shows that in each band-shaped area BA of the main area NAm, the nozzle 11 of the jth nozzle row 29 is positioned at the ith position from the -D1 side. However, the band-shaped area BA and / or the periodic pattern are set so that the nozzle 11 of the first nozzle row 29 is positioned at the first position. This table also includes a table for Example 1, so please refer to the table for Example 1 to confirm the correspondence between j and i and FIG. 9.

[0152] The exemplified nozzle arrangement can increase the distance between the nozzles 11. Alternatively, if the distance between the nozzles 11 arranged in this manner is longer than a predetermined distance, the entire nozzle arrangement may be contracted in the direction D2. In this case, the size of the head 7 in the direction D2 can be reduced. In this case, for example, the widths of the supply sub-common flow path 19S and the recovery sub-common flow path 19C may be left unchanged, and the distance between the supply sub-common flow path 19S and the recovery sub-common flow path 19C may be shortened.

[0153] It should be noted that the arrangement of the nozzles 11 in the nozzle group 27 can be made 180° rotationally symmetrical, not limited to the third to tenth examples, by making the periodic pattern 180° rotationally symmetrical.

[0154] (6. Summary of embodiments) As described above, the nozzle plate 41N according to the embodiment has an ejection surface 9a and a plurality of nozzle groups 27. The ejection surface 9a extends in a first direction (D1 direction and x direction) and a second direction (D2 direction and y direction) that are orthogonal to each other. Each of the plurality of nozzle groups 27 has a plurality of nozzles 11 that open to the ejection surface 9a and are aligned in the D1 direction. Each nozzle group 27 is configured with a plurality of parallel nozzle rows 29 (n rows), each of which has a plurality of nozzles 11 aligned in a direction intersecting the D2 direction. In the entirety of the plurality of nozzle groups 27, the plurality of nozzles 11 are aligned at intervals (C1 / n) corresponding to the resolution D [dpi] when viewed in the D2 direction, except for both end portions in the D1 direction (the sub-regions NAs on both sides). In each nozzle group 27, when the first point P1 to the fourth point P4 are defined as described above, the shape formed by the lines connecting the first point P1, the second point P2, the fourth point P4, the third point P3, and the first point P1 in that order is a parallelogram. When C1=25.4 / D×n, C2=2×C1 / n×(n-1), and the ranges of the values ​​of A1, A2, A3, A5, C1, and C2 are the ranges exemplified in the previous section, formulas (I) to (IV) hold, and Wx≧2Wy and Wf>L2 hold.

[0155] Therefore, for example, by setting θ and α, etc., relating to the parallelogram of the nozzle area NA, the nozzle plate 41N ensures an area for various flow paths (see L1 and L2), while reducing the likelihood of the overall size (Wx and Wy) becoming large. When printing on a wide medium 101, Wx is usually made wider, and the nozzle plate 41N becomes larger. In this case, for example, the initial cost of equipment for manufacturing such a large nozzle plate 41N (and other components of the head 7) is likely to be high. Furthermore, manufacturing errors are likely to be large. Meanwhile, in this embodiment, Wx is set to A5 or less because formula (IV) is satisfied. This reduces the likelihood of the above-mentioned inconvenience occurring.

[0156] A liquid ejection device according to an embodiment (e.g., ejection unit 5) has a plurality of nozzle plates 41N according to an embodiment as described above. The plurality of nozzle plates 41N are arranged in the direction D1. When the range of the value of A4 is the range exemplified in the previous section, formula (V) holds.

[0157] Therefore, for example, the above-described effects are achieved not only by the head 7 alone but also by the discharge unit 5. When formula (V) is satisfied, for example, a line-type head capable of printing on a relatively wide medium 101 is realized.

[0158] The recording apparatus (printer 1) according to the embodiment includes the liquid ejection apparatus (ejection unit 5) according to the embodiment described above, and a conveying device 31. The conveying device 31 moves the ejection unit 5 and the recording medium (media 101) relative to each other in the direction D2. The printer 1 can enjoy the above-mentioned effects because it includes the ejection unit 5 according to the embodiment.

[0159] The technology according to the present disclosure is not limited to the above-described embodiments and may be implemented in various forms.

[0160] For example, the recording device is not limited to those generally classified as printers. For example, the recording device may be a plotter. Furthermore, for example, the recording device may be a device in which a liquid ejection device is moved by a robot to print on a stationary recording medium, or a handheld printer in which a liquid ejection device is moved by hand to print on a stationary recording medium. As can be understood from the above, the transport device is not limited to one that moves the recording medium, but may also be one that moves the liquid ejection device, or one that moves both the liquid ejection device and the recording medium.

[0161] Furthermore, for example, the liquid is not limited to ink, but may be paint or a conductive material for patterning a circuit board (however, either can be considered as a type of ink.) Furthermore, for example, the liquid may be one that exhibits the properties of a Newtonian fluid, or one that exhibits the properties of a non-Newtonian fluid (e.g., pseudoplasticity).

[0162] Furthermore, for example, the media is not limited to paper, and may be, for example, resin, cloth, wood, metal, or ceramic. Furthermore, the media is not limited to paper (film)-like objects, and may be, for example, plate-like objects, car bodies, or buildings.

[0163] The nozzle plate and the liquid ejection device may be used for purposes other than recording. For example, the nozzle plate may be used for ejecting a chemical substance from the nozzles toward another chemical substance to cause a chemical reaction. [Explanation of symbols]

[0164] 1...printer (recording device), 3...ejection system, 5...ejection unit (liquid ejection device), 7...head, 9...flow path member, 9a...ejection surface, 11...nozzle, 27...nozzle group, 29...nozzle row, 41N...nozzle plate.

Claims

1. an ejection surface extending in a first direction and a second direction perpendicular to each other; a plurality of nozzle groups each having a plurality of nozzles opening on the ejection surface and aligned in the first direction, wherein n is an integer equal to or greater than 2, and each of the nozzle groups is configured with n rows of nozzles arranged in parallel to one another, the rows having a plurality of the nozzles arranged in a direction intersecting the second direction; In the entirety of the plurality of nozzle groups, the plurality of nozzles are arranged at intervals corresponding to a resolution of D [dpi] when viewed in the second direction, excluding both end portions in the first direction, One side of the first direction is referred to as a first side, and the other side is referred to as a second side, one side of the second direction is a third side, and the other side is a fourth side; In each of the nozzle groups, a first point is a position of the nozzle located closest to the first side in the nozzle row located closest to the third side; a second point is a position of the nozzle located closest to the second side in the nozzle row located closest to the third side; a third point is a position of the nozzle located closest to the first side in the nozzle row located closest to the fourth side; When the position of the nozzle located furthest to the second side in the nozzle row located furthest to the fourth side is defined as a fourth point, a shape formed by lines sequentially connecting the first point, the second point, the fourth point, the third point, and the first point is a parallelogram, a first side connecting the first point and the second point is inclined at an angle θ with respect to the first direction so as to be positioned toward the fourth side as it approaches the second side, the angle θ being greater than 0° and less than 90°; a second side connecting the first point and the third point is inclined at an angle α with respect to the first direction so as to be positioned toward the fourth side as it approaches the second side, the angle α being greater than the angle θ and less than 90°; The number of the plurality of nozzle groups is N ｂ year, N ｂ the length of the entire nozzle group in the first direction is Wx [mm], N ｂ the length of the entire nozzle group in the second direction is Wy [mm], The length of the first side is r １ [mm], The length of the second side is r ２ [mm], The distance between the first side and the side opposite to the first side is L2 [mm], C1=25.4 / D×n, Let C2 = 2 × C1 / n × (n-1), 2 mm≦A １ ≦10 mm, 10 mm≦A ２ ≦50 mm, 20 mm≦A ３ ≦100 mm, 50 mm≦A ５ ≦300 mm, When Wf [mm] is defined as a value obtained by adding C2 to the length from the third point of the nozzle group located closest to the first side to the second point of the nozzle group located closest to the second side, The following formulas (I) to (IV) are satisfied: (A １ -C1sinα) / (sinθcosα)≦r １ (I) A ２ / sin (α-θ)≦r ２ (II) () ３  １ sinθ)osinα≧r ２ (III) (A ５ -C1(N ｂ -1)-N ｂ r １ cosθ) / cosα≧r ２ (IV) And Wx≧2Wy and Wf>L2 are satisfied. Nozzle plate.

2. a plurality of nozzle plates according to claim 1 arranged in the first direction; The number of the plurality of nozzle plates is N ｈ year, 5 inches≦A ４ When it is ≦50 inches, (N ｈ N ｂ r １ cosθ+(N ｈ N ｂ -1)C1+C2-A ４ ) / cosα≧r ２ (V) holds true, Liquid discharge device.

3. The liquid ejection device according to claim 2; a conveying device that moves the liquid ejection device and the recording medium relatively in the second direction; A recording device having:

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