JP2010194770A - Liquid droplet delivery device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a manufacturing error in PZT burning, even when nozzles are formed with high density or with a large number, and to simplify constitution. <P>SOLUTION: A printing head 3 includes the first and second nozzle lines (first and second nozzle line groups A, B) arrayed with the plurality of nozzles along a paper sheet feed direction X at a prescribed interval. The first and second nozzle lines are provided with a space larger than the prescribed interval along the paper sheet feed direction X. The printing head 3 includes the first piezoelectric actuator 12A for imparting selectively pressure to a liquid in the plurality of nozzles 11a, in the plurality of nozzles 11a belonging to the first nozzle line, and the second piezoelectric actuator 12B, that is another piezoelectric actuator other than the first piezoelectric actuator 12A, for imparting selectively pressure to a liquid in the plurality of nozzles, in the plurality of nozzles belonging to the second nozzle line. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a droplet discharge apparatus such as an ink jet printing apparatus.

  In an inkjet printing apparatus that prints on recording paper by ejecting ink droplets from a plurality of nozzles of a print head, the nozzle density and the number of nozzles are increased in the print head in order to achieve high speed and high image quality. In order to increase the nozzle density and the number of nozzles, it is usually necessary to lengthen the print head and drive it serially.

  However, in the case of a print head using a piezoelectric actuator (PZT), it is necessary to fire PZT. Therefore, if the PZT becomes large due to the increase in length, the warpage of the PZT may occur at the time of firing, or manufacturing errors (firing errors). ) Gets bigger. In addition, as the nozzle density is increased and the number of nozzles is increased, the intervals between the electrical wirings are also reduced.

  By the way, two piezoelectric actuators are arranged adjacent to one long common liquid chamber (manifold), and an ink introduction port (ink supply port) is arranged at one end of the common liquid chamber. Is known (for example, see Patent Document 1).

  With such a structure, the piezoelectric actuator is divided and configured, so that the enlargement of PZT can be avoided and the error due to PZT firing can be reduced.

JP 10-34923 A

However, although the technique described in Patent Document 1 has a configuration in which two piezoelectric actuators are arranged adjacent to each other, the interval between the piezoelectric actuators necessary for joining the piezoelectric actuators becomes an interval greater than the nozzle pitch. Therefore, the pressure chamber is inclined in order to make the interval between the piezoelectric actuators the same as the nozzle pitch, but this makes the flow path configuration complicated.

An object of the present invention is to provide a droplet discharge device that can reduce manufacturing errors during PZT firing even when the nozzle density is increased or the number of nozzles is increased, and the flow path configuration is simple.

According to a first aspect of the present invention, there is provided a droplet discharge head that discharges droplets, a head moving unit that reciprocates the droplet discharge head in a predetermined direction, and a medium conveyance of a droplet discharge medium orthogonal to the predetermined direction. A liquid droplet ejection apparatus including a medium conveyance unit configured to convey in a direction, wherein the liquid droplet ejection head includes first and second nozzle arrays in which a plurality of nozzles are arranged at predetermined intervals in the medium conveyance direction. And the first and second nozzle rows are provided with an interval larger than the predetermined interval in the medium transport direction, and for the plurality of nozzles belonging to the first nozzle row, A first piezoelectric actuator that selectively applies pressure to the liquid in the plurality of nozzles, and a piezoelectric actuator different from the first piezoelectric actuator, the plurality of nozzles belonging to the second nozzle row Relative to a second piezoelectric actuator for selectively applying pressure to the liquid within those plurality of nozzles, characterized in that it comprises.

  In this way, the size of the piezoelectric actuator can be made smaller than that of a single piece, so that the manufacturing error during firing is reduced as compared with the case of increasing the nozzle density and the number of nozzles with a single piece. it can. In addition, the first and second nozzle rows are provided in the medium transport direction at a larger interval than the predetermined interval, and it is possible to realize high density nozzles and multiple nozzles with a simple flow path configuration. it can.

  Further, if the interval between the nozzle rows is sufficiently large, there is a sufficient space between the piezoelectric actuators, so that the piezoelectric actuators can be joined easily, and wiring for each piezoelectric actuator is sufficient. The number of electrical wirings connected to one piezoelectric actuator is reduced, and wiring work is facilitated.

  According to a second aspect of the present invention, in the liquid droplet ejection apparatus according to the first aspect, the manifold of liquid supplied to each nozzle of the first and second nozzle rows is the first and second nozzles. A plurality of liquid supply ports that are common to the row and supply the liquid to each manifold may be arranged between the first and second nozzle rows.

  In this way, since a plurality of liquid supply ports for supplying liquid to each manifold are arranged in the nozzle-free region between the nozzle rows, not only can the wasteful space be used effectively, It is possible to reduce the distance from the liquid supply port to the nozzle far from the liquid supply port, and to prevent the occurrence of non-ejection of ink due to insufficient supply of ink.

  In this case, as described in claim 3, in the droplet discharge device according to claim 1 or 2, the droplet discharge head has a length in the nozzle row direction of each of the first and second nozzle rows. Assuming L, an interval larger than the predetermined interval between the first and second nozzle rows is a length corresponding to the sum of the length L and a length corresponding to twice the nozzle pitch in each nozzle row. do it.

  In this way, after the liquid droplets are discharged from the first and second nozzle rows, the liquid droplets can be continuously discharged by moving the sum of the length L and the nozzle pitch. It is possible to discharge droplets at high speed without forming them.

  In the liquid droplet ejection apparatus according to claims 1 to 3, the control unit is driven and controlled as follows when droplets are ejected from one liquid droplet ejection medium.

  For example, according to a fourth aspect of the present invention, in the liquid droplet ejection apparatus according to any one of the first to third aspects, the control means for driving and controlling the head moving means, the medium conveying means, and the first and second piezoelectric actuators is provided. And the controller is configured so that the number of times of use of each nozzle row is equal or the number of times of use of one nozzle row is equal to that of the other nozzle row when droplets are ejected on the one liquid droplet ejection medium. When the drive control is performed so that the number of uses is one more than the number of uses, and the number of uses of each nozzle row is equal, the drive control is repeated for each droplet ejection medium, while the number of uses of the one nozzle row is repeated. Is one more than the number of times of use of the other nozzle row, the number of times of use of the other nozzle row is one time higher than the number of times of use of the one nozzle row for the next droplet discharge medium. To be It is possible to control.

According to a fifth aspect of the present invention, in the liquid droplet ejection apparatus according to the fourth aspect, the control means is configured such that when the number of uses of the one nozzle row is one more than the number of uses of the other nozzle row. When the one nozzle row is the first nozzle row on the upstream side in the medium transport direction, the one-time use becomes the last of the droplet discharge operation, and the one nozzle row In the case of the second nozzle row on the downstream side in the medium conveyance direction, the one-time use may be controlled to be the beginning of the droplet discharge operation.

  According to a sixth aspect of the present invention, in the liquid droplet ejection apparatus according to the fourth or fifth aspect, the control unit performs the first and second liquid droplet ejection operations on one liquid droplet ejection medium. In the case where droplets are ejected using both nozzle rows, the feed amount of the droplet ejection medium is set to an amount corresponding to the sum of the length L of the nozzle rows and the nozzle pitch after an odd number of uses. On the other hand, after the even-numbered use, an amount corresponding to the sum of three times the length L of the nozzle row and three times the nozzle pitch can be used.

  According to a seventh aspect of the present invention, in the liquid droplet ejection apparatus according to the fourth or fifth aspect, the control unit performs the first liquid droplet ejection operation on one liquid droplet ejection medium in the second nozzle row. Droplets using only the first and second nozzle rows across the portion where the second droplet ejection operation ejected droplets in the first droplet ejection operation. In this case, after the odd-numbered use, the feed amount of the droplet discharge medium is set to an amount corresponding to the sum of the length L of the nozzle row and the nozzle pitch, while the even-numbered after-use Then, it may be an amount corresponding to the sum of three times the length L of the nozzle row and a length corresponding to three times the nozzle pitch.

  According to a eighth aspect of the present invention, in the liquid droplet ejection apparatus according to the fourth or fifth aspect, the control unit performs the first liquid droplet ejection operation on one liquid droplet ejection medium only in the second nozzle row. The first and second nozzles are ejected at a portion on the downstream side of the medium transport direction from the portion where the second droplet ejection operation ejects the droplet in the first droplet ejection operation. When ejecting droplets using a row, the amount of droplet ejection medium fed is equivalent to three times the length L of the nozzle row and three times the nozzle pitch after an odd number of uses. While the amount is equivalent to the sum of the length, it is also possible to make the amount equivalent to the sum of the length L of the nozzle row and the nozzle pitch after the even-numbered use.

  Since the present invention is configured as described above, since the size of the piezoelectric actuator is smaller than that of a single sheet, the nozzle density can be increased and the number of nozzles can be increased without increasing the firing error. I can plan. If the distance between the first and second piezoelectric actuators is sufficiently large, the joining process of the piezoelectric actuators is facilitated, and the wiring work may be performed for each piezoelectric actuator, and the number of electrical wirings for each piezoelectric actuator is small. Therefore, the wiring work is facilitated.

1 is a schematic configuration diagram illustrating a schematic configuration of an ink jet printing apparatus (droplet discharge apparatus) according to an embodiment of the present invention. It is explanatory drawing which shows the relationship between the cavity unit which concerns on this invention, a piezoelectric actuator, and a flexible wiring board (COP). It is a top view which shows the relationship between the cavity unit which concerns on this invention, and a piezoelectric actuator. It is a block diagram which shows the electrical structure of the control means of the said inkjet printing apparatus. (A)-(f) is explanatory drawing which shows an example of the printing control pattern of the printing head based on this invention, respectively. (A)-(f) is explanatory drawing which shows another example of the printing control pattern of the printing head based on this invention, respectively. (A)-(f) is explanatory drawing which shows another example of the printing control pattern of the printing head based on this invention, respectively. (A)-(f) is explanatory drawing which shows the other example of the printing control pattern of the printing head based on this invention, respectively. It is a flowchart figure which shows the flow of control by a control means. It is a flowchart figure which shows the flow of another control by a control means.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an inkjet printing apparatus 1 as an embodiment of a droplet discharge apparatus according to the present invention has a printing paper P (covered paper) on the lower surface of a carriage 2 on which an ink cartridge (not shown) is mounted. A print head 3 (droplet discharge head) that discharges ink droplets for printing on a droplet discharge medium) is provided. The carriage 2 is supported by a carriage shaft 5 and a guide plate (not shown) provided in the printer frame 4, and in a scanning direction Y (predetermined direction) orthogonal to the paper feed direction X (medium transport direction) of the printing paper P. The carriage drive motor 56 (head moving means), which will be described later, is configured to reciprocate. A printing paper P conveyed by a conveyance motor 55 (medium conveyance means), which will be described later, in a paper feeding direction X from a paper feeding unit (not shown) is introduced between a platen roller (not shown) and the print head 3, Predetermined printing is performed by the ink ejected from the print head 3 toward the printing paper P, and then the paper is discharged by the paper discharge roller 6.

  As shown in FIGS. 2 and 3, the print head 3 includes a cavity unit 11 and piezoelectric actuators (first and second piezoelectric actuators 12 </ b> A and 12 </ b> B) in order from the lower side, and the first and second First and second flexible wiring boards 13A and 13B (signal lines) for supplying drive signals are provided on the upper surfaces of the piezoelectric actuators 12A and 12B, respectively.

  The cavity unit 11 is provided with a vibration plate on the upper side of a laminate composed of a plurality of plate members, and is not specifically shown, but communicates with each of the plurality of nozzles 11a and the plurality of nozzles as is well known. A plurality of pressure chambers 11b and a manifold 11c for temporarily storing ink to be supplied to the pressure chambers 11b are included, and the plurality of nozzles 11a and the plurality of pressure chambers 11b communicate with each other.

  The print head 3 (cavity unit 11) has a plurality of first and second nozzle rows in which a plurality of nozzles are arranged at a predetermined interval (a predetermined nozzle pitch) in the paper feed direction X. These first and second nozzle rows are provided in the paper feed direction X with an interval larger than the predetermined interval, and form a nozzle row for one color. A first nozzle row group A in which a plurality of first nozzle rows are provided in parallel corresponding to each color, and a second nozzle row group in which a plurality of second nozzle rows are provided in parallel corresponding to the respective colors. B is provided at the interval, and the entire nozzle group is formed. As shown in FIG. 3, the interval is the length between the first and second nozzle rows for each color (that is, the length in the nozzle row direction of the first and second nozzle row groups A and B). Let L be the sum of the length L and a length corresponding to twice the nozzle pitch α in each nozzle row, and a length corresponding to L + 2α.

  Piezoelectric actuators 12A and 12B for selectively ejecting ink (liquid) in the pressure chambers are bonded (fixed) to the upper side of the diaphragm corresponding to the nozzle row groups A and B, respectively. . As a result, the size of each piezoelectric actuator 12A, 12B can be half that of a single piezoelectric actuator, so manufacturing errors (firing errors) of the piezoelectric actuators 12A, 12B are reduced.

The first piezoelectric actuator 12A selectively applies pressure to the ink in the plurality of nozzles 11a with respect to the plurality of nozzles 11a belonging to the first nozzle row group A (first nozzle row). . The second piezoelectric actuator 12B, which is a piezoelectric actuator different from the first piezoelectric actuator 12A, has a plurality of nozzles 11a belonging to the second nozzle row group B (second nozzle row). A pressure is selectively applied to the liquid in the nozzle 11a.

  An ink manifold 11c supplied to each nozzle 11a of the first and second nozzle rows is common to the first and second nozzle rows. Between the first and second nozzle array groups A and B (first and second nozzle arrays), a plurality of ink supply ports 11d (liquid supply ports) for supplying ink of each manifold 11c are arranged, The ink supply port 11d is provided with a filter (not shown) for capturing dust contained in the ink.

  Each of the piezoelectric actuators 12A and 12B is formed by sequentially laminating a plurality of piezoelectric layers made of a lead zirconate titanate (PZT) ceramic material (piezoelectric sheet) having ferroelectricity, and is driven by the piezoelectric layer. Electrodes to be used (electrodes to which a voltage is applied and earth electrodes having a ground potential) are provided.

  Next, the electrical configuration of the control means (control unit 54) of the inkjet printing apparatus will be described with reference to FIG. 4 which is a block diagram.

  First, the control unit 54 stores a CPU 51 that is an arithmetic device, a ROM 52 that stores various control programs and data executed by the CPU 51, and print data and control signals input from an input device (for example, a personal computer). And a RAM 53 which is a memory for performing the above.

  The CPU 51, ROM 52, and RAM 53 are connected to each other via a bus line 58, and the bus line 58 is connected to an input / output port 59.

  The input / output port 59 can print on the printing paper P by driving a drive unit 57 having the print head 3, the transport motor 55, and the carriage drive motor 56.

  In the print head 3, nozzles for ejecting ink onto the printing paper P are formed. Then, cyan, magenta, yellow, and black ink supplied from the ink cartridge (not shown) to the print head 3 are ejected from the nozzles, and an image is formed on the printing paper P.

  The transport motor 55 is a motor that rotationally drives a transport roller and a paper discharge roller that transport the printing paper P, and a carriage drive motor 56 supplies a driving force that reciprocates the carriage 2 on which the print head 3 is mounted. is there.

  The CPU 51 develops print data input from the input device 60 via the interface 61 into print data that can be printed by the print head 3, and outputs the data to the print head 3 as an ejection signal for each nozzle. is there. By driving the print head 3 in accordance with the ejection signal, ink is ejected from each nozzle and printing is performed on the printing paper P, and the carriage drive motor 56 and the transport motor 55 are output to the print head 3. Driven in synchronization with the discharge signal.

By the way, the frequency of use related to the life of the print head 3 is made equal between the first and second nozzle arrays (first and second nozzle array groups A and B), and the number of scans (pass number) required for printing is small. There is a demand to do. Here, equalizing the usage frequency is not only when the usage frequency when printing one sheet of printing paper P becomes equal, but also when the usage frequency becomes equal every time several printing papers P are printed. Including.

  Therefore, when printing on one printing paper P, the control unit 54 makes the number of uses of each nozzle row equal, or the number of uses of one nozzle row is 1 more than the number of uses of the other nozzle row. When the number of uses of each nozzle row is equal, the drive control is repeated for each printing paper P, while the number of uses of the one nozzle row is the use of the other nozzle row. When the number of times is greater than the number of times, the next printing paper P is controlled so that the number of times of use of the other nozzle row is greater than the number of times of use of the one nozzle row.

  When the number of times of use of the one nozzle row is one more than the number of times of use of the other nozzle row, the one nozzle row is the first nozzle row (upstream in the paper feed direction X) In the case of the first nozzle row group A), the one-time use increases at the end of the printing operation, and the one nozzle row is the second nozzle row (second) on the downstream side in the paper feed direction X. In the case of the nozzle row group B), the above-mentioned one-time use is controlled to be the beginning of the printing operation.

  Next, a specific print control pattern when printing using the print head 3 will be considered.

First, the print head 3 has a portion not having the nozzle row and not printing the range of the width L between the portions having the first and second nozzle row groups A and B that print the range of the width L, respectively. Therefore, printing is performed with two width L portions (first and second nozzle row groups A and B) in the forward direction, and on the return, the two width L portions (first and second nozzle row groups A and B). If the printing is performed in (), a portion four times the width L can be printed in a reciprocating manner. Based on this, the printing range is a multiple of 4 times the width L (Case1
Print head 3 depending on whether it is larger than width L (displayed as Case2), twice as large as width L (displayed as Case3), or three times larger than width L (displayed as Case4). The control content of the drive is changed.

As will be described later, the print control patterns for Cases 1 to 4 are
It is classified into the following three types.
(Α-TYPE)
The first printing operation for one printing paper P is a case where printing is performed using both the first and second nozzle array groups A and B, and the feed amount of the printing paper P is set to an odd number after use. Is an amount corresponding to the sum of the nozzle row length L and the nozzle pitch, but after an even-numbered use, an amount corresponding to the sum of three times the nozzle row length L and the nozzle pitch. Things to do.
(Β-TYPE)
The first printing operation on one printing paper P is printed using only the second nozzle row group B, and the second printing operation is sandwiched between the portions printed by the first printing operation. And the second nozzle array group A and B, and the printing paper P feed amount is set to the sum of the length L of the nozzle array and the nozzle pitch after the odd-numbered use. On the other hand, after the even-numbered use, the amount corresponds to the sum of three times the nozzle row length L and the nozzle pitch.
(Γ-TYPE)
The first printing operation on one printing paper P is printed using only the second nozzle array group B, and the second printing operation is more in the paper transport direction than the portion printed by the first printing operation. In the case where printing is performed using the first and second nozzle array groups A and B in the downstream portion, the feed amount of the printing paper P is set to the length L of the nozzle array after the odd-numbered use. An amount corresponding to the sum of three times the nozzle pitch and an amount corresponding to the sum of the length L of the nozzle row and the nozzle pitch after the even-numbered use.

Next, print control patterns for Cases 1 to 4 will be described with reference to FIGS. In each figure, the number of scans in which printing is performed is indicated by a circled number.
-Case 1-
The print width is represented by L × (4n + 4) (n = 0, 1, 2, 3,...). As a print control pattern, for example, when n = 1, as shown in FIG. 5A, printing is performed by both nozzle array groups A and B in the forward direction, and printing is also performed by both nozzle array groups A and B. α-TYPE, as shown in FIG. 5 (b), printing is performed with only one nozzle row group B in the forward direction, printing is performed with both nozzle row groups A and B on the return side, and the other nozzle is further moved once again .Beta.-TYPE to be printed in the row group A, as shown in FIG. 5C, printing is performed only with one nozzle group B in the forward direction, and the return is made by increasing the feed amount of the printing paper P to return both nozzle row groups A, Any one of γ-TYPE is used in which printing is performed using B and then printing is performed one more time and printing is performed using the other nozzle array group A. In each TYPE, the nozzle array groups A and B are used twice, but the number of scans (pass number) is only α-TYPE, and β and γ-TYPE are both three. is there.

In the case of n = 2, as shown in FIG. 5D, printing is performed twice with both nozzle array groups A and B, and the printing with both nozzle array groups A and B is repeated twice as shown in FIG. -TYPE, as shown in FIG. 5 (e), printing is performed with only one nozzle row group B in the forward direction, and printing is performed with both nozzle row groups A and B in the forward direction, and then with both nozzle row groups A and B in the forward direction. Printing is performed on both sides of the nozzle group A and B, and finally the printing is performed one more time and the other nozzle array group A is printed, as shown in FIG. 5 (f). Printing is performed with only one nozzle row group B, and the return is printed with both nozzle row groups A and B by increasing the feed amount of the printing paper P, and then printing is performed with both nozzle row groups A and B. Either γ-TYPE is used, in which printing is performed by both nozzle row groups A and B, and then printed one more time by the other nozzle row group A. In this case, the nozzle array groups A and B are used four times for any TYPE, but the number of scans (pass number) is only four for α-TYPE, and both β and γ-TYPE are used. 5 times.
-Case 2-
The print width is represented by L × (4n + 1) (n = 0, 1, 2, 3,...). As for the print control pattern, when n = 1, as shown in FIG. 6A, printing is performed with both nozzle array groups A and B in the forward direction, and the printing is performed with both nozzle array groups A and B, and further, Α-TYPE to be printed once again with the other nozzle row group A, as shown in FIG. 6B, printing is performed only with one nozzle row group B in the forward direction. Printing with B, then printing with the other nozzle row group A, and then going back one more time and printing with the other nozzle row group A, as shown in FIG. Printing is performed only with the nozzle array group B, and on the return side, the printing paper P is increased in feed amount, printing is performed with both nozzle array groups A and B, and printing is performed with both nozzle array groups A and B one more time. -TYPE is adopted. In any TYPE, either one of the nozzle array groups A and B is used twice and the other is used three times, but the number of scans (pass number) is 3 for both α and γ-TYPE. , Β-TYPE is 2 times.

In the case of n = 2, as shown in FIG. 6 (d), printing with both nozzle array groups A and B in the forward direction and printing with both nozzle array groups A and B are repeated twice, as shown in FIG. Further, α-TYPE is printed once again by the other nozzle row group A, as shown in FIG. 6E, and only one nozzle row group B is printed in the forward direction. , B, and then printing with both nozzle rows A and B, then printing with both nozzle rows A and B, going back and printing with both nozzle rows A and B, Finally, β-TYPE is printed one more time and printed by the other nozzle row group A, and the return is also printed by the nozzle row group A, as shown in FIG. Only, and on the return side, the printing paper P is increased in feed amount and printed with both nozzle groups A and B, and then forward with both nozzle groups A and B. On the return side, the printing operation is performed with both nozzle row groups A and B, and one of γ-TYPE printing is performed with both nozzle row groups A and B going one more time. In any TYPE, the frequency of use of either one of the nozzle array groups A and B is 4 and the other is 5; however, the number of scans (pass number) is 5 for both α and γ-TYPE. , Β-TYPE is 6 times.
-Case 3-
The print width is represented by L × (4n + 2) (n = 0, 1, 2, 3,...). As for the printing control pattern, when n = 1, as shown in FIG. 7A, printing is performed with both nozzle array groups A and B in the forward direction, and printing is performed with both nozzle array groups A and B, and then Α-TYPE, which is printed with the other nozzle row group A and then goes one more time and printed with the other nozzle row group A, as shown in FIG. Β-TYPE for printing, printing on both nozzle arrays A and B, printing on both nozzle arrays A and B, and printing on the other nozzle array A on the return As shown in FIG. 7 (c), printing is performed with only one nozzle row group B in the forward direction, and on the return side, printing is performed with both nozzle row groups A and B by increasing the feed amount of the printing paper P, and then is sent once more. Thus, either γ-TYPE is used in which printing is performed by both nozzles A and B and then printing is performed by the other nozzle array group A. In each TYPE, the number of scans is four, but the frequency of use is four for the α-TYPE, four for the nozzle row group A, twice for the nozzle row group B, and β, γ-TYPE for any nozzle row. 3 times.

In the case of n = 2, as shown in FIG. 7 (d), printing with both nozzle row groups A and B in the forward direction and printing with both nozzle row groups A and B are repeated twice, as shown in FIG. Finally, α-TYPE is printed one more time, printing with the other nozzle row group A, and then returning with the nozzle row group A. As shown in FIG. Is printed with only the nozzle group A and B on the return side, then with both nozzle group groups A and B on the way back, and with both nozzle group groups A and B on the return side, and finally another one. Printing with both nozzle rows going back and printing with only the other nozzle row group A on the return side, as shown in FIG. 7 (f), printing with only one nozzle row group B in the forward direction, On the return side, the printing paper P is increased in feed amount, printing is performed with both nozzle row groups A and B, and then printing is performed with both nozzle row groups A and B in the forward direction. Either γ-TYPE is used, in which printing is performed by both nozzle row groups A and B, and is further printed once by both nozzle rows, and then is printed only by the other nozzle row group A. In both patterns, the number of scans is 6, but the frequency of use is 6 for the nozzle row group A and 4 times for the nozzle row group B only for α-TYPE, and β, γ-TYPE for all nozzle rows. 5 times.
-Case 4-
The print width is represented by L × (4n + 3) (n = 0, 1, 2, 3,...). As for the print control pattern, when n = 1, as shown in FIG. 8 (a), printing is performed with both nozzle array groups A and B in the forward direction, and printing is performed with both nozzle array groups A and B in the forward direction. Α-TYPE is printed by going back and forth with both nozzle row groups A and B, and printing with the other nozzle row group A on the return side, as shown in FIG. Β-TYPE, which is printed, the return is printed by both nozzle row groups A and B, is further printed once by both nozzle row groups A and B, and the return is also printed by both nozzle row groups A and B, As shown in FIG. 8 (c), printing is performed by only one nozzle row group B in the forward direction, and on the return side, printing is performed by both nozzle row groups A and B with the feeding amount of the printing paper P being increased, and going once more. Print with both nozzles A and B, then print with the other nozzle row group A, and then go back and print with nozzle row group A only once more γ-TYPE One is adopted. In any of the patterns, the frequency of use is 4 times for one of the nozzle rows and 3 for the other, but the number of scans is 4 times for α, β-TYPE and 5 times for γ-TYPE.

In the case of n = 2, as shown in FIG. 8 (d), printing with both nozzle array groups A and B in the forward direction and return printing with both nozzle array groups A and B are repeated twice. Finally, the nozzle array groups A and B are printed one more time, and the return is printed by only the nozzle array group A. As shown in FIG. Printing is performed only with group B, the return is printed with both nozzle row groups A and B, then is printed with both nozzle row groups A and B, the return is printed with both nozzle row groups A and B, and finally Β-TYPE, which is printed once again by both nozzle row groups A and B, and the return is printed by both nozzle row groups A and B, as shown in FIG. Printing is performed using only B, and on the return side, the printing paper P is increased in feed amount, printing is performed using both nozzle groups A and B, and then the printing is performed using both nozzle groups A and B. Printing, the return prints with both nozzle groups A and B, and then goes one more time and prints with both nozzle groups A and B. On the return, only the other nozzle group A prints, and finally the nozzle Any one of γ-TYPE, which is printed once more only in the column group A, is employed. In any pattern, the frequency of use is 5 times for one of the nozzle rows and 6 times for the other, but the number of scans is 6 times for α, β-TYPE and 7 times for γ-TYPE.

  Next, the flow of processing by the control unit 54 will be described with reference to FIG.

  When the power is turned on, image data is first received (step S1), and information about the print length P per print sheet P is acquired from the image data (step S2).

  It is determined whether or not the relationship between the printing length H and the nozzle row length L satisfies any of the following relational expressions (1) and (2) (step S3).

L × (4n + 1) <H ≦ L × (4n + 2) (1)
L × (4n + 3) <H ≦ L × (4n + 4) (2)
When either of the relational expressions (1) and (2) is satisfied, a print control pattern in which the usage frequency of the nozzle row group A and the nozzle row group B is the same in Case 1 or Case 3 based on FIGS. 5 and 7 is selected. (Step S4), printing is performed (Step S5), and the process returns to Step S2. As a result, the nozzle array group A and the nozzle array group B have the same use frequency and substantially the same service life.

  On the other hand, when none of the relational expressions (1) and (2) is satisfied, it is Case 2 or Case 4, so it is determined whether or not the cumulative use frequency of each nozzle row is the same (step S6). In this case, an arbitrary print control pattern is selected based on FIGS. 6 and 8 (step S7), the cumulative use frequency of each nozzle row is stored (step S8), and printing is executed (step S5). If the cumulative use frequency of each nozzle row is different, a print control pattern that uses many nozzle rows with a low cumulative use frequency is selected based on FIGS. 6 and 8 (step S9), and the cumulative use of each nozzle row is selected. The frequency is stored (step S8), and printing is executed (step S5). Thereby, since the nozzle array group A and the nozzle array group B are controlled in the direction in which the use frequency is the same, it is advantageous in that the service life is also made approximately the same.

  The process only controls the nozzle usage frequency to be the same in each nozzle row (that is, including the case where the number of printing passes is not minimized), but the nozzle usage frequency is the same and the printing pass is the same. It is also possible to control the number to be minimized.

  In this case, as shown in FIG. 10, when the power is turned on, image data is first received (step S11), and information about the print length P per print sheet P is obtained from the image data. (Step S12).

The relationship between the printing length H and the nozzle row length L is expressed by the following relational expression L × (4n + 3) <H ≦ L × (4n + 4) (3)
It is determined whether or not the condition is satisfied (step S13).

  If the relational expression (3) is satisfied, it is Case 1, so that an α-TYPE print control pattern is selected based on FIG. 5 (step S14), printing is performed (step S15), and the process returns to step S12.

If the relational expression (3) is not satisfied, then the relation between the printing length H and the nozzle row length L is expressed by the following relational expression L × (4n + 1) <H ≦ L × (4n + 2) (4 )
It is determined whether or not the condition is satisfied (step S16).

  If the relational expression (4) is satisfied, it is Case 3, so that a printing control pattern of β-TYPE or γ-TYPE is selected based on FIG. 7 (step S17), printing is executed (step S15), Return to S12.

When the relational expression (4) is not satisfied, the relation between the printing length H and the nozzle row length L is further expressed by the following relational expression L × (4n + 4) <H ≦ L × (4n + 3) (5)
It is determined whether or not the condition is satisfied (step S18).

  If the relational expression (5) is satisfied, since it is Case 2, it is determined whether or not the cumulative use frequency of each nozzle row is the same (step S19). If the same, α-TYPE is based on FIG. Is selected (step S20), the cumulative use frequency of each of the nozzle array groups A and B is stored (step S21), printing is performed (step S15), and the process returns to step S12. For example, a γ-TYPE print control pattern is selected based on FIG. 6 (step S22), printing is performed (step S15), and the process returns to step S12.

  If the relational expression (5) is not satisfied, it is Case 4, so it is determined whether or not the cumulative usage frequency of each nozzle row is the same (step S23). A TYPE print control pattern is selected (step S24), the cumulative use frequency of each nozzle row is stored (step S21), printing is performed (step S15), and the process returns to step S12. 8 selects a β-TYPE print control pattern (step S25), stores the cumulative use frequency of each nozzle array (step S21), executes printing (step S15), and returns to step S12.

  Thereby, control is performed so that the nozzle use frequency is the same and the number of print passes is minimized.

  In addition to the above, the present invention can be implemented with the following modifications.

(i) The present invention is not limited to the case where the droplet discharge head is an ink jet type print head, and a colored liquid is applied as fine droplets, or a wiring pattern is formed by discharging a conductive liquid. The present invention can also be applied to other droplet discharge heads.

  (ii) Not only printing paper but also various materials such as resin and cloth can be used as the liquid droplet ejection medium, and not only ink but also various liquids such as colored liquid and functional liquid can be ejected. Can be used.

1 Inkjet printing device (droplet ejection device)
3 Print head (droplet discharge head)
11a Nozzle 11b Pressure chamber 11c Manifold 11d Ink supply port 12A, 12B Piezoelectric actuator 54 Control unit (control means)
55 Transport motor (medium transport means)
56 Carriage drive motor (head moving means)
A 1st nozzle row group B 2nd nozzle row group

Claims (8)

A droplet discharge head for discharging droplets;
A head moving means for reciprocating the droplet discharge head in a predetermined direction;
A droplet discharge device comprising: a medium transfer means for transferring a droplet discharge medium in a medium transfer direction orthogonal to the predetermined direction;
The droplet discharge head is
A plurality of nozzles have first and second nozzle arrays arranged in the medium transport direction at a predetermined interval, and the first and second nozzle arrays have an interval larger than the predetermined interval in the medium transport direction. Is provided,
further,
A first piezoelectric actuator that selectively applies pressure to the liquid in the plurality of nozzles with respect to the plurality of nozzles belonging to the first nozzle row;
A second piezoelectric actuator different from the first piezoelectric actuator, which selectively applies pressure to the liquid in the plurality of nozzles to the plurality of nozzles belonging to the second nozzle row. An actuator,
A droplet discharge device comprising:
The manifold of liquid supplied to each nozzle of the first and second nozzle rows is common to the first and second nozzle rows,
The liquid droplet ejection apparatus according to claim 1, wherein a plurality of liquid supply ports that supply liquid to each manifold are arranged between the first and second nozzle rows.
In the droplet discharge head, when the length in the nozzle row direction of the first and second nozzle rows is a length L, an interval larger than the predetermined interval between the first and second nozzle rows is 3. The droplet discharge device according to claim 1, wherein the droplet discharge device has a length corresponding to a sum of a length L and a length corresponding to twice the nozzle pitch in each nozzle row.
Control means for driving and controlling the head moving means, the medium conveying means, and the first and second piezoelectric actuators;
The controller is configured so that the number of times of use of each nozzle row is equal or the number of times of use of one nozzle row is equal to the number of times of use of the other nozzle row when ejecting droplets on the one droplet ejection medium. Drive control to be more than once,
When the number of uses of each nozzle row is equal, while repeating its drive control for each droplet discharge medium,
When the number of times of use of the one nozzle row is one more than the number of times of use of the other nozzle row, for the next droplet discharge medium, the number of times of use of the other nozzle row is equal to the one nozzle row. The droplet discharge device according to claim 1, wherein the droplet discharge device is controlled to be one more than the number of times of use.
When the number of times of use of the one nozzle row is one more than the number of times of use of the other nozzle row, the control means causes the one nozzle row to move the first nozzle row upstream of the medium transport direction. In the case of a nozzle row, the one-time use becomes the last of the droplet discharge operation, and when the one nozzle row is the second nozzle row on the downstream side in the medium transport direction, 5. The droplet discharge device according to claim 4, wherein the control is performed so that the use once is started at the beginning of the droplet discharge operation.
When the first droplet ejection operation for one droplet ejection medium ejects droplets using both the first and second nozzle rows, the control means feeds the droplet ejection medium. The amount is set to an amount corresponding to the sum of the length L of the nozzle row and the nozzle pitch after the odd-numbered use, while the nozzle length is three times the length L of the nozzle row after the even-numbered use. 6. The droplet discharge device according to claim 4, wherein the amount is equivalent to a sum corresponding to a length corresponding to three times the pitch.
The control unit discharges a droplet using a second nozzle row only for a first droplet discharge operation for one droplet discharge medium, and performs a second droplet discharge operation for the first liquid. When droplets are ejected using the first and second nozzle rows across the portion where droplets are ejected by the droplet ejection operation, the feed amount of the droplet ejection medium is set to an odd number after use. While the amount corresponds to the sum of the nozzle row length L and the nozzle pitch, after the even-numbered use, the length corresponding to 3 times the nozzle row length L and 3 times the nozzle pitch 6. The droplet discharge apparatus according to claim 4, wherein the amount is equivalent to the sum of the two.
  The control means performs the first droplet ejection operation on one droplet ejection medium using only the second nozzle row, and the second droplet ejection operation performs the first droplet ejection operation. When droplets are ejected using the first and second nozzle arrays to a portion downstream of the medium transport direction from the portion where droplets are ejected in the droplet ejection operation, the droplet ejection medium is fed. The amount is set to an amount corresponding to the sum of three times the length L of the nozzle row and the length corresponding to three times the nozzle pitch after the odd-numbered use, while the nozzle row after the even-numbered use. The droplet discharge device according to claim 4 or 5, wherein the amount is equivalent to the sum of the length L of the nozzle and the nozzle pitch.

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