JP4715143B2 - Ink jet recording head and ink jet recording apparatus - Google Patents

Description

  The present invention relates to an ink jet recording head and an ink jet recording apparatus, and more particularly, to an ink jet recording head including a plurality of ejector units in which ejectors for ejecting ink droplets are arranged, and an ink jet recording apparatus including the ink jet recording head.

  2. Description of the Related Art Conventionally, an inkjet recording head (hereinafter referred to as “matrix arrangement head”) in which ejectors for ejecting ink droplets are two-dimensionally arranged in a matrix is known (Patent Document 1, etc.).

  FIG. 15A shows a basic structure of a conventional matrix arrangement head. In the matrix arrangement head 242, a plurality of ejectors 244 are arranged two-dimensionally. By ejecting ink droplets from each ejector, as shown in FIG. 15B, the print dots 250 are formed so as to be arranged at equal intervals Pn so as to have a predetermined resolution. As described above, since the ejectors are arranged at equal intervals Pn in the direction indicated by the arrow S in the figure, this direction is referred to as an ejector arrangement direction in the following description. In these matrix arrangement heads 242, a plurality of ejectors 244 are connected by respective common flow paths 246, and a plurality of common flow paths 246 are connected by a second common flow path 248. For example, in the matrix arrangement head 242 shown in FIG. 15A, the common flow path 246 is arranged along the row direction of the head matrix (indicated by the arrow M), and the second common flow path 248 is the column direction of the matrix. (It is synonymous with the ejector arrangement direction and is indicated by an arrow S.).

  The ejectors (244A to 244H) connected to the same common flow path 246 are arranged by being shifted by Pn in the ejector arrangement direction, and by ejecting ink droplets from each ejector while controlling the ejection timing, As shown in FIG. 15B, dots 250 are formed at a pitch Pn.

  However, the conventional matrix arrangement head has a problem that periodic uneven density (non-uniform dot diameter) occurs.

  There are various reasons why periodic density unevenness is likely to occur in the matrix arrangement head. Particularly, in the case of nozzles arranged in a matrix, depending on the position of the ejector on the nozzle surface, the ejection characteristics of the ejector (for example, the volume of ink droplets, It is easy to cause a change in the ink droplet discharge speed.

  In general, it is impossible to manufacture a head without causing variations in ejection characteristics of the ejectors, and the ejection characteristics of the ejectors tend to increase as the ejectors are physically separated from each other. For example, in the case of manufacturing a head by stacking members such as substrates, a deviation in the rotation direction between the stacked members causes a difference in ejection characteristics between the ejectors.

  There are other factors that cause a difference in ejection characteristics depending on the distance between the ejectors. For example, positioning accuracy when forming and processing the nozzle is one of them. In order not to vary the discharge characteristics, it is necessary to accurately position the nozzle with respect to the ejector. Factors that influence the positioning accuracy include a difference in scale between the processing apparatus and the matrix arrangement head, and a shift in the rotational direction between the two. When these are displaced, the displacement of the nozzle position with respect to the ejector and therefore the nozzle position with respect to the ejector is enlarged, resulting in a change in the ejection characteristics.

  Hereinafter, such a change in ejection characteristics depending on the position of the ejector is referred to as “ejection characteristic distribution”. For example, when printing is performed with a matrix arrangement head having an ejection characteristic distribution in the row direction, as shown in FIG. 15B, a dot diameter change with a period of n occurs in the recorded dot row. That is, in the recorded image, density unevenness having a period of n in the ejector arrangement direction occurs.

Further, a long inkjet recording head has been proposed in which the matrix arrangement head is used as a unit and a plurality of the units are connected in the ejector arrangement direction (Patent Document 2). When connecting a plurality of head units in this way, it is common to arrange adjacent units so as to overlap each other.
Japanese Patent No. 2806386 JP 2003-31959 A Japanese Patent Laid-Open No. 2004-167982

  However, by overlapping the units, there is a problem that the periodicity of the density unevenness is disturbed at the joint of the units, and the density unevenness becomes conspicuous.

  Further, the present inventors have proposed a technique for making the recording image uniform by increasing the frequency of density unevenness due to the “ejection characteristic distribution” by devising the ejector arrangement of the matrix arrangement head ( Patent Document 3) has a problem that if the periodicity of density unevenness is disturbed, sufficient effects cannot be obtained even if this technique is applied.

  The present invention has been made to solve the above problems, and an object of the present invention is to suppress density unevenness in an ink jet recording head having a plurality of units in which ejectors for ejecting ink droplets are arranged in a matrix. An object of the present invention is to provide an ink jet recording head capable of recording a high quality image and an ink jet recording apparatus provided with the ink jet recording head.

In order to achieve the above object, an inkjet recording head according to the present invention includes a plurality of units in which ejectors for ejecting ink droplets are arranged in a two-dimensional matrix, wherein the column direction of the matrix is the width direction of the recording medium and the matrix Are arranged in such a manner that the row direction is perpendicular to the width direction of the recording medium, and an image is formed on the recording medium while moving relative to the recording medium in a direction perpendicular to the width direction of the recording medium. The plurality of units are arranged in a staggered manner so that adjacent units overlap in the row direction of the matrix, and the period in the column direction of the matrix is the plurality of units. is arranged to be constant between the units, each of the plurality of units, the ink droplet ejected onto the recording medium The ejector is oscillated in the column direction of the matrix, and the ejector is oscillated in the row direction of the matrix of the ejector when the ejector follows the ejector in the column direction of the matrix. In the portion where the adjacent units overlap each other, the ejectors in the corresponding rows of the adjacent units are arranged on the same straight line in the relative movement direction. In addition, the number of ejectors driven by the units adjacent to each other may be increased or decreased along the ejector arrangement direction.

  In order to achieve the above object, an ink jet recording apparatus of the present invention includes the ink jet recording head of the present invention.

  In the ink jet recording head of the present invention, since the plurality of units are arranged so that the period in the column direction of the matrix is constant among the plurality of units, the generation period of density unevenness is not disturbed. Therefore, it is possible to record high-quality images while suppressing uneven density. For example, the plurality of units are arranged so that the period in the column direction of the matrix is continuous between adjacent units.

  In the above-described ink jet recording head, each of the plurality of units may be arranged with the ejector so that the dot diameter of the ink droplet ejected on the recording medium vibrates in the column direction of the matrix. it can. For example, in each of the plurality of units, the ejector is arranged such that the position in the row direction of the matrix of the ejector vibrates when the ejector is followed in the ejector arrangement direction. Thereby, the frequency of the density unevenness is increased, and the density unevenness is further suppressed.

  It is preferable that the number of effective ejectors included in each of the plurality of units is an integer multiple of the number of columns of the matrix. The number of columns of the matrix is preferably an odd number. Further, in a portion where adjacent units overlap, the number of ejectors driven by each unit may be increased or decreased along the ejector arrangement direction.

  According to the present invention, an inkjet recording head having a plurality of units in which ejectors for ejecting ink droplets are arranged in a matrix can produce an effect that density unevenness can be suppressed and a high-quality image can be recorded.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Overall configuration of inkjet recording apparatus)
FIG. 1 is a diagram showing a configuration of an ink jet recording apparatus according to an embodiment of the present invention.

  The inkjet recording apparatus 10 includes an inkjet recording head 12 that records an image by discharging ink. The ink jet recording head 12 includes four recording heads 14C, 14M, 14Y, and 14K corresponding to each color of C (cyan), M (magenta), Y (yellow), and K (black). In the following description, an initial letter corresponding to each color is added to the code when distinguishing each color, and an initial letter corresponding to each color is omitted unless otherwise distinguished.

  Each recording head 14 is a long head having a recording area equal to or larger than the width of the recording paper. The configuration of the recording head 14 will be described later.

  Ink tanks 16 </ b> C, 16 </ b> M, 16 </ b> Y, and 16 </ b> K are provided corresponding to the recording heads 14. The ink stored in the ink tank 16 is supplied to the recording head 14 corresponding to each color through a pipe (not shown).

  In the vicinity of the inkjet recording head 12, a maintenance unit that performs cleaning or the like for preventing clogging of the ink of each recording head 14 at a predetermined timing, for example, a non-image recording timing such as when the inkjet recording apparatus 10 is activated. 15 is provided corresponding to each recording head 14.

  The maintenance unit 15 is positioned on both sides of the inkjet recording head 12 as shown in FIG. 1 during image recording, and moved to a position facing each nozzle 11 of the inkjet recording head 12 as shown in FIG. 2 during maintenance. Is configured to do. Note that the configuration of the maintenance unit 15 is not limited to this, and any configuration may be used as long as the maintenance unit 15 can be disposed so as to face each nozzle 11 of the inkjet recording head 12 during maintenance.

  The ink jet recording apparatus 10 includes a paper feed tray 18 that stores recording paper. The recording paper supplied from the paper feed tray 18 is conveyed by a plurality of roller pairs 20 and supplied to the ink jet recording head 12. Is done. An endless belt-like transport body 24 wound around rollers 22A and 22B is provided at a position facing the ink jet recording head 12, and the endless belt-like transport body 24 is rotated by the rotation of the rollers 22A and 22B. The recording sheet conveyed by the roller pair 20 is conveyed to a position facing the inkjet recording head 12 by the endless belt-shaped conveyance body 24.

  A suction roller 26 is provided at a position facing the roller 22B. The recording paper conveyed by the plurality of roller pairs 20 is attracted to the endless belt-shaped transport body 24 by being charged by the suction roller 26 and being pressed by the endless belt-shaped transport body 24.

  A plurality of roller pairs 28 and transport rollers 30 are provided on the downstream side of the endless belt-shaped transport body 24 in the recording paper transport direction. The recording paper on which the image is recorded by the ink jet recording head 12 is conveyed by the plurality of roller pairs 28 and the conveying roller 30 and is discharged to the paper discharge tray 32.

  Further, the inkjet recording apparatus 10 includes a reversing path 33 for double-sided recording. The reversing path 33 is composed of a plurality of roller pairs 35, and the recording paper on which an image is recorded on one side by the ink jet recording head 12 is reversed by the reversing path 33 and conveyed to a position again facing the ink jet recording head 12. Is done. This makes it possible to record images on both sides of the recording paper.

(Electrical configuration of inkjet recording apparatus)
FIG. 3 is a block diagram for explaining the electrical configuration of the ink jet recording apparatus. The inkjet recording apparatus 10 includes a control device 74 that includes a CPU, a ROM, and a RAM. The control device 74 includes an input interface 72 for receiving image data from the terminal device 70, an image processing device 76 that performs image processing such as halftone processing on the input image data, and each recording head 14. A head driver 78 to be driven and a motor driver 80 for driving a paper conveyance device such as the conveyance roller 20 and the maintenance unit 15 are connected.

  In the inkjet recording apparatus 10, when image data is input from the input interface 72, the input image data is input to the image processing device 76 via the control device 74, and halftone processing is performed by the image processing device 76. . The halftone-processed image data is input to the control device 74, and the control device 74 converts the image data into a selection signal that selects a drive signal in accordance with the gradation of the halftone image. The head driver 78 selects a drive signal having a predetermined drive voltage waveform based on the selection signal generated by the control device 74, and drives each recording head 14 by this drive signal.

  That is, a drive voltage waveform corresponding to image information is applied to a piezoelectric actuator included in an ejector constituting each recording head 14, and an ink droplet is ejected from the ejector by the action of the generated pressure wave. A detailed ink droplet ejection mechanism will be described later.

(Configuration of recording head)
As shown in FIG. 4, the recording head 14 has a plurality of units 112 in which ejectors for ejecting ink are arranged in a matrix and are alternately arranged in a staggered manner in the width direction of the recording paper. In this example, a total of eight units 112 are arranged in two rows by four. Each of the plurality of units 112 is separated from each other so as not to mechanically interfere. Since the ejectors are arranged along the width direction of the recording paper, this direction is referred to as an ejector arrangement direction. The ejector array direction corresponds to the “matrix column direction”, and the direction orthogonal to the ejector array direction corresponds to the “matrix row direction”.

  By moving the recording paper relative to the recording head 14, each unit 112 prints a band-like region (band) that is long in the paper traveling direction so as to be aligned in the width direction of the recording paper. Recording can be performed.

  5 to 7, the unit 112 is partially shown. The direction indicated by the arrow S is the “column direction (ejector arrangement direction)”, and the direction indicated by the arrow M is the “row direction”. As shown in FIG. 6, the unit 112 has a laminated flow path plate 114. The laminated flow path plate 114 is formed by aligning and laminating a total of 5 plates including a nozzle plate 116, a common flow path plate 118, a supply path plate 120, a pressure generation chamber plate 122, and a vibration plate 124, and adhesive layers, etc. It is formed by joining by a joining means. In the pressure generation chamber plate 122, the supply path plate 120, and the common flow path plate 118, two long holes 126, 128, and 130 are formed in parallel along the matrix row direction, and the common flow path plate 118, In a state where the supply path plate 120 and the pressure generation chamber plate 122 are stacked, the second common flow path 132 (see FIG. 5) is configured by the long holes 126, 128, and 130.

  An ink supply hole 134 is formed in the vibration plate 124 at a position corresponding to the center of each second common flow path 132. An ink supply device (not shown) is connected to the ink supply hole 134.

  The common flow path plate 118 is common to a plurality of (in this embodiment, 11 per long hole 130 (second common flow path 132)) continuously from the long holes 130 and along the column direction of the matrix. A flow path 136 is formed, and the liquid flows in the common flow path 136 in a state where the supply path plate 120, the common flow path plate 118, and the nozzle plate 116 are stacked.

  In the pressure generation chamber plate 122, a plurality of pressure generation chambers 142 (three per one common flow path 136 in the present embodiment, 66 in the whole unit 112) are formed along the common flow path 136, respectively. Corresponding to the pressure generating chamber 142, a single plate type piezoelectric actuator 144 as a pressure generating means is attached to the diaphragm 124 (see FIG. 7). Further, as can be seen from FIG. 5, the supply path plate 120 has one ink supply path 146, one for each pressure generation chamber 142, so that the pressure generation chamber 142 is positioned substantially diagonally when viewed in plan. In addition, an ink discharge path 148 is formed. Further, the common flow path plate 118 and the nozzle plate 116 are formed with a communication path 150 and an ink discharge port 152 at positions corresponding to the ink discharge paths 148, respectively. The ink discharge path 148, the communication path 150, and the ink discharge port 152 constitute a nozzle 140. Further, the pressure generating chamber 142, the nozzle 140, and the piezoelectric actuator 144 constitute an ejector 138.

  Accordingly, as can be seen from the cross-sectional view of FIG. 7, a continuous ink passage is configured from the common flow path 136 to the pressure generation chamber 142, the ink discharge path 148, the communication path 150, and the ink discharge port 152. Become. Ink sent from an ink supply device (not shown) is supplied to the unit 112 through the ink supply hole 134 and filled into the pressure generation chamber 142 from the second common flow path 132 through the respective common flow paths 136. Is done. Here, when a drive voltage waveform corresponding to image information is applied to the piezoelectric actuator 144, the piezoelectric actuator 144 is bent and deformed, and the pressure generating chamber 142 is expanded or compressed. As a result, when a volume change occurs in the pressure generation chamber 142, a pressure wave is generated in the pressure generation chamber 142. By the action of the pressure wave, the ink in the nozzle 140 (the ink discharge path 148, the communication path 150, and the ink discharge port 152) moves and is discharged from the ink discharge port 152 to form an ink droplet.

  8A schematically shows the arrangement of the nozzles 140 (ejectors 138) of the unit 112. FIG. As can be seen from the above description, the nozzles 140 are provided at the same position with respect to each of the ejectors 138, and the relative positional relationship of each nozzle 140 is the same as the relative positional relationship of each ejector 138. The same applies.

  The plurality of nozzles 140 are arranged in a matrix with the number of columns of the matrix being 11, and the matrix pitch Nm in the row direction and the matrix pitch Ns in the column direction. That is, when the nozzles 140 (ejectors 138) are sequentially followed in the ejector arrangement direction, as an example, the droplets are in the order of the nozzles 140A-140F-140K-140E-140J-140D-140I-140C-140H-140B-140G. Each nozzle 140 is arranged so that the dots are ejected and the dots are arranged in the ejector arrangement direction.

  The unit 112 is assumed to have a plurality of ejector groups 168. One ejector group 168 includes 11 nozzles 140A to 140K, and the nozzles 140 (for example, the nozzles 140B and 140C and the nozzles 140C and 140D) adjacent in the row direction have twice the nozzle pitch p. (It is assumed that this is d).

  In the present embodiment, the number of columns in the matrix is eleven. However, the number of columns may be an odd number, for example, another odd number of columns such as nine. Since the distance d between adjacent rows is twice the nozzle pitch p, by setting the number of rows to an odd number, the relationship between the distances between adjacent pixel rows in the ejector arrangement direction becomes constant, and the arrangement of the nozzles is easy. become.

  Next, the arrangement of two adjacent units 112 will be described. As shown in FIG. 9, the two adjacent units 112 are arranged such that the ejectors 138 in the same row (D row in FIG. 9) of the overlapping ejector group 168 are arranged on the same line in the paper traveling direction. . As a result, the period in the column direction of the matrix is continuous between adjacent units, and the matrix pitch Ns in the ejector array direction is constant across the units 112.

  Further, since one ejector 138 in the overlap portion is not used, the number of ejectors 138 used in the single unit 112 (hereinafter referred to as “effective ejector number”) is an integral multiple of the number of columns. . For example, in FIG. 9, the number of columns from A to K is 11, and the effective number of ejectors is 66, six times that number.

  In the present embodiment, by adopting the arrangement of the nozzle 140 described above, the position of the nozzle 140 (ejector 138) in the row direction vibrates when the nozzle 140 (ejector 138) is sequentially followed in the ejector arrangement direction. Thus, a periodic change in the dot diameter in the ejector arrangement direction is suppressed, and the recorded image has high uniformity.

  This point will be described in detail below. In the following, the vibration of the position in the row direction of the nozzle 140 (ejector 138) when the nozzle 140 (ejector 138) is sequentially followed in the ejector arrangement direction is referred to as “vibration of the matrix nozzle arrangement”.

  In general, in an inkjet recording head having nozzles arranged in a matrix, the volume of ink droplets ejected from each nozzle varies depending on the position of the ejector in the laminated flow path plate 114 (see FIGS. 6 and 7). A linear discharge characteristic distribution is shown. For example, in the case of a droplet discharge head having the same configuration as that of the present embodiment, ink is ejected depending on the position of the ejector as shown in FIG. There is a tendency for drop size (or drop volume) to change. Although there is a tendency that the droplet volume also changes in the column direction, here, first, a change in the droplet volume in the row direction is considered.

  When such a drop volume changes, a dot diameter change pattern is generated on the recording medium as in the conventional case shown in FIG. That is, when the dots of the ink droplets ejected by the ejectors 244A-244B-244C-244D-244E-244F-244G-244H connected in the row direction are arranged at a constant pitch p in the ejector array direction, the ejector array A pattern of periodic dot diameter changes with the matrix pitch Ns as a period appears in the direction.

  FIG. 11 shows the relationship between the dot number and the density in the ejector arrangement direction in the conventional matrix arrangement head. Also from this graph, it can be seen that the density periodically changes with the matrix pitch Ns in the ejector array direction as a period, and a pattern of dot diameter changes appears.

  On the other hand, in the unit 112 of this embodiment, as described above, when the nozzles 140 (ejectors 138) are sequentially followed in the ejector arrangement direction, the rows of the nozzles 140 (ejectors 138) vibrate. When the dots 158 are viewed along the ejector arrangement direction, their sizes vibrate alternately (see FIG. 8B).

  Also, as shown in FIG. 12, in the relationship between the dot number and the density in the ejector arrangement direction, the density oscillates with a fluctuation period of two rasters. Furthermore, as shown in FIG. 13, even when the relationship between the raster and the density in the ejector arrangement direction between adjacent units is seen, the density oscillates with a constant fluctuation cycle. As described above, since the dots 158 on the recording paper P vibrate when viewed in the ejector arrangement direction, fluctuations in the dot diameter in the ejector arrangement direction are suppressed, and the fluctuation of the dot diameter fluctuation period is eliminated. The recorded image has high uniformity.

  As described above, in the ink jet recording apparatus according to this embodiment, a plurality of units in which ejectors that eject ink are arranged in a matrix are used in a staggered manner across the width direction of the recording paper. However, since the ejectors are arranged so that the matrix pitch Ns in the ejector arrangement direction is constant across the units, the density unevenness generation period is not disturbed and the density unevenness is not noticeable.

  For each unit, the ejector is arranged so that the size of the dot diameter oscillates when viewed in the ejector arrangement direction, so the density unevenness period due to the “ejection characteristic distribution” is increased and the density unevenness is suppressed. Is done.

  In the above-described embodiment, the configuration is such that one of the ejectors in the overlap portion is not used for printing, but the ejectors in the overlap portion can be used selectively in terms of time. For example, in the overlap portion, the number of used ejectors of two overlapping units may be increased or decreased along the ejector arrangement direction. As a result, the joints of the units become inconspicuous.

  Specifically, as shown in FIG. 14A, when the number of dots formed in the paper traveling direction is 5, the overlap portion is formed by the unit 1 as it approaches the unit 2 from the unit 1. Adjust the ejector so that the number of dots gradually decreases to 5, 4, 3, and so on, and the number of dots formed by unit 2 gradually increases to 0, 1, 2, and so on. It can be driven in time division. At this time, as shown in FIG. 14B, the dots formed by the unit 1 do not have to be continuous in the ejector arrangement direction.

1 is a schematic diagram illustrating a configuration of an ink jet recording apparatus according to an embodiment of the present invention. It is the schematic which shows the arrangement structure at the time of the maintenance of the inkjet recording device of FIG. It is a block diagram for demonstrating the electrical structure of the inkjet recording device of FIG. It is a top view which shows the structure of an inkjet recording head. It is a top view which shows typically the arrangement | positioning of the ejector of each unit, a common flow path, and a 2nd common flow path. It is a disassembled perspective view which shows the plate structure of each unit. It is sectional drawing which shows the ejector of each unit. (A) is a plan view schematically showing the arrangement of ejectors of each unit, and (B) is an explanatory diagram showing dots formed by ink droplets ejected from this unit. It is a top view which shows typically arrangement | positioning of the ejector of two adjacent units. It is a graph which shows qualitatively the general relationship between the position of an ejector in the row direction and the size of an ink droplet. It is a graph which shows the relationship between the raster and the density | concentration in the conventional matrix arrangement | positioning head. It is a graph which shows the relationship between the raster and density in each unit. It is a graph which shows the relationship between the raster and density | concentration in two adjacent units. (A) And (B) is a figure which shows the arrangement | sequence of the dot formed by each unit, when the ejector of an overlap part is driven by a time division. (A) is a plan view schematically showing an ejector array of a conventional matrix array droplet discharge head, and (B) is an explanatory diagram showing dots formed by droplets discharged from this droplet discharge head. is there.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inkjet recording apparatus 11 Each nozzle 12 Inkjet recording head 14 Each recording head 15 Maintenance unit 16 Ink tank 18 Paper feed tray 20 Conveyance roller 22A Roller 22B Roller 24 Endless belt-shaped conveyance body 26 Adsorption roller 28 Roller pair 30 Conveyance roller 32 Paper discharge Tray 33 Reverse path 35 Roller pair 70 Terminal device 72 Input interface 74 Control device 76 Image processing device 78 Head driver 80 Motor driver 112 Unit 114 Laminated channel plate 116 Nozzle plate 118 Common channel plate 120 Supply channel plate 122 Pressure generation chamber plate 124 Diaphragm 126 Long hole 130 Long hole 132 Common flow path 134 Ink supply hole 136 Common flow path 138 Ejector 140 Nozzle 142 Pressure generating chamber 144 Piezoelectric actuator 14 The ink supply path 148 ink discharge path 150 communicating path 152 ink discharge ports 158 dots 168 ejector group Nm matrix pitch Ns matrix pitch P recording paper Pn pitch p nozzle pitch

Claims (4)

A plurality of units in which ejectors for ejecting ink droplets are arranged in a two-dimensional matrix are such that the column direction of the matrix is the width direction of the recording medium and the row direction of the matrix is perpendicular to the width direction of the recording medium. An inkjet recording head that records an image on the recording medium while moving relative to the recording medium along a direction orthogonal to the width direction of the recording medium,
The plurality of units are arranged in a staggered manner so that adjacent units overlap in the row direction of the matrix, and are arranged so that the period in the column direction of the matrix is constant among the plurality of units. ,
Each of the plurality of units, said ejector when the size of the dot diameter of ink droplets ejected onto the recording medium with vibrating in the column direction of said matrix, followed the the ejector in the column direction of said matrix The ejectors are arranged in a plurality of columns in the column direction of the matrix so that the position of the matrix in the row direction vibrates.
In the portion where the units adjacent to each other overlap, the ejectors in the corresponding rows of the units adjacent to each other are arranged so as to be aligned on the same straight line in the relative movement direction, and the ejectors driven by the units adjacent to each other Characterized in that the number of is increased or decreased along the ejector arrangement direction,
Inkjet recording head.   The inkjet recording head according to claim 1, wherein the number of effective ejectors included in each of the plurality of units is an integral multiple of the number of columns of the matrix.   The ink jet recording head according to claim 1, wherein the number of columns of the matrix is an odd number.   An ink jet recording apparatus comprising the ink jet recording head according to claim 1.

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