JP2009083296A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder equipped with a nozzle array driving power source, which drives a plurality of nozzle arrays, has a simple circuit constitution, and is low-cost. <P>SOLUTION: Nozzle array voltage converting parts 2-1 and 2-2 are equipped with: both dropper regulators 2-1-2-1 to 2-2-2-2 respectively corresponding to nozzle arrays 22-1 to 22-4; and switching regulators 2-1-1 and 2-2-1 which convert an output voltage of a main power source 8 that supplies an electric power for driving all of the nozzle arrays 22-1 to 22-4, and output the voltage to the dropper regulators 2-1-2-1 to 2-2-2-2. The dropper regulators 2-1-2-1 to 2-2-2-2 step down a voltage outputted from the switching regulator 2-1-1 or 2-2-1, and impress it to those corresponding to themselves among the nozzle arrays 22-1 to 22-4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image recording technique for recording an image by ejecting ink onto a recording medium such as paper or film, and more particularly, to a power source technique for driving a recording head in an inkjet image recording apparatus.

  In the ink jet type image recording apparatus, as shown in FIG. 13, in order to obtain a high resolution image using a low resolution recording head (hereinafter, “recording head” is also referred to as “nozzle row”), The nozzle rows 22-1 and 22-2 are divided into two in the main scanning direction with respect to the nozzle pitch (the nozzle pitches provided at equal intervals in the main scanning direction in the nozzle rows 22-1 and 22-2, respectively). A method of forming a nozzle row capable of forming a high-resolution image by laminating and pasting each other is used. In this way, a recording head having a configuration in which a plurality of recording heads are bonded together to enable high-resolution image formation is called a bonding head.

  Here, as illustrated in FIG. 14, the bonding head 23-1 configured by bonding the nozzle rows 22-1 and 22-2 and the nozzle rows 22-3 and 22-4 are bonded to each other. The laminating head 23-2 is disposed so that the end thereof overlaps with the length α when viewed in the sub-scanning direction (recording medium conveyance direction) perpendicular to the main scanning direction. Further, as shown in FIG. 15, a bonding head 23-3 formed by bonding nozzle rows 22-5 and 22-6, and a bonding formed by bonding nozzle rows 22-7 and 22-8. A head 23-4, a bonding head 23-5 configured by bonding nozzle rows 22-9 and 22-10, and a bonding head 23 configured by bonding nozzle rows 22-11 and 22-12. Similarly, -6 is arranged so that its end portions overlap. In FIG. 15, by arranging the bonding heads 23-1 to 23-6 in this way, the recording medium 24 has a length that is equal to or greater than the width (the length that is greater than the length in the conveyance direction of the recording medium 51). A line head which is a recording head is configured.

  FIG. 16 shows the relationship between the pixels formed by performing image formation with the recording head configured by combining the bonding head 23-1 and the bonding head 23-2 and the density of image recording at that time. .

  As can be seen from FIG. 16, in the range of the length α that is an overlapping portion of the bonding head 23-1 and the bonding head 23-2, the nozzle density is twice that of the other portions. For this reason, if image recording is performed by ejecting ink from all the nozzles in this range, the image recording density of the overlapping portion becomes high, and a seam is visible in the recorded image.

  In order to avoid this problem, as shown in FIG. 17, in the range of the length α which is an overlapping portion, the overlapping portion is not overlapped by recording by thinning out the number of pixels to be formed. A technique has been proposed in which the concentration is equal to that of the portion.

  In addition, when performing image recording with a plurality of bonding heads, the density difference and density gradient of the recorded images are different for each nozzle row. An operation is performed in which the density of the recording image is adjusted to be approximately the same for each nozzle row constituting the alignment head, and further, the density of the bonding heads disposed adjacent to each other is adjusted to be approximately the same.

In such an inkjet type image recording apparatus that performs image recording using a plurality of bonding heads, for example, as disclosed in Patent Document 1, a nozzle row driving power source capable of adjusting the nozzle row driving voltage for each nozzle row. Some use a switching regulator.
JP 2002-264308 A

  However, when the technique disclosed in Patent Document 1 described above is applied to a full-line type image recording apparatus including a plurality of nozzle rows, it is necessary to provide a switching regulator as a nozzle row driving power source for each nozzle row. .

  Since a switching regulator uses a switching element for voltage conversion, generally high conversion efficiency can be obtained. However, compared with a dropper regulator that generates a voltage drop by releasing Joule heat and converts the voltage, the number of parts is large and the circuit is complicated, so the cost of the nozzle row driving power source is high.

  Accordingly, in view of the above-described problems, an object of the present invention is to provide an ink jet recording apparatus that includes a nozzle row driving power source that drives a plurality of nozzle rows and has a simple circuit configuration and a low cost.

  In order to achieve the above-described object, an ink jet recording apparatus according to an aspect of the present invention is an ink jet recording apparatus having a plurality of nozzle arrays in which a plurality of nozzles that eject ink are arranged in a straight line. A plurality of dropper regulators associated with each nozzle row, and a switching regulator that converts an output voltage of a power source that supplies power for driving all of the nozzle rows and outputs the converted voltage to the dropper regulator. At least a nozzle row voltage conversion unit is provided, and the dropper regulator is configured to step down and apply a voltage output from the switching regulator to a nozzle row associated with the dropper regulator.

  An ink jet recording apparatus according to another aspect of the present invention includes an ink jet recording apparatus having a plurality of nozzle arrays in which a plurality of nozzles that eject ink are arranged in a straight line. A plurality of bonding heads are configured to be bonded one by one, and a plurality of dropper regulators are associated with each bonding head, and a plurality are associated with each bonding head. A switching regulator, and at least a nozzle row voltage converter, the switching regulator converts an output voltage of a power source that supplies power for driving all of the nozzle rows, and is attached to the switching regulator. One of the two nozzle arrays constituting the alignment head is connected to the converted electric power. The dropper regulator steps down the converted voltage to the nozzle row to which the switching regulator does not apply the converted voltage, out of the two nozzle rows associated with the dropper regulator. It is characterized by applying.

  According to the present invention, it is possible to provide an ink jet recording apparatus having a simple and low-cost nozzle array driving power source that drives a plurality of nozzle arrays.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a conceptual block configuration of an inkjet image recording apparatus according to this embodiment. FIG. 2 schematically shows an arrangement example of the ink jet image recording apparatus according to the present embodiment.

  The control unit 1 controls the entire image recording apparatus 9, and includes a medium detection unit 6, a transport mechanism 7, nozzle row drive units 21-1 to 21-2m of the recording units 5-1 to 5-n, and a nozzle row. The voltage converter 2 (2-1 to 2-m) and a feeding mechanism (not shown) are controlled in an integrated manner. The control unit 1 also includes a storage unit 3 that stores various setting information set in the nozzle array voltage conversion units 2-1 to 2-m, and an image included in job information sent from the host apparatus 11. A plane memory 4 for storing data.

  The recording medium conveyance unit 7 controls conveyance of a recording medium (recording material) (not shown). The recording medium is placed on the basis of an instruction from the control unit 1 and conveyed downstream in the conveyance path. . In addition, the recording medium transport unit 7 includes a transport information generation unit 32 for generating transport information of the recording medium when transporting the recording medium.

The medium detection unit 6 is a sensor that detects a recording medium conveyed downstream from the sheet feeding mechanism (not shown) in the conveyance path.
The nozzle array driving units 21-1 to 21-2m of the recording units 5-1 to 5-n record an image based on the image data on a recording medium in accordance with an instruction from the control unit 1, and On the other hand, it has nozzle rows (recording heads) 22-1 to 22-2m for performing image recording.

  The nozzle row voltage conversion units 2-1 to 2-m convert the voltage of the power supplied from the main power supply 8 into appropriate voltage values for driving the nozzle rows 22-1 to 22-2m, and The power is supplied to the column driving units 21-1 to 21-2m. The appropriate voltage value is stored in the storage unit 3 in the control unit 1.

The nozzle rows 22-1 to 22-2m are formed by arranging a plurality of nozzles that eject ink in a straight line.
The image recording apparatus 9 includes at least one feeding unit (not shown) disposed on the most upstream side of the conveyance path of the recording medium 51 and a medium detection unit 6 disposed on the downstream side of the conveyance path of the feeding unit. And a recording medium transport unit 7 disposed further downstream of the transport path, recording units 5-1 to 5-n disposed to face the recording medium transport unit 7, and an operation process according to the present invention. And a control unit 1 that performs overall control of the entire image recording apparatus.

  In response to an instruction from the control unit 1, the feeding unit conveys a plurality of recording media 51 loaded and stored in a feeding tray (not shown) one by one to the downstream side of the conveyance path. It is.

  The medium detection unit 6 includes, for example, an optical transmission sensor, detects the leading or trailing end of the recording medium 51 conveyed from the feeding unit, and notifies the control unit 1 of the detection information. .

  The recording medium transport unit 7 includes an endless belt in the transport member 31, for example, a driven roller 41 a in which the transport information generation unit 32 is connected to the rotation shaft and a drive roller 41 b in which the transport mechanism drive unit 33 is connected to the rotation shaft. Is constructed. Further, a platen (not shown) having a plurality of holes is provided below the endless belt, and a suction fan (not shown) is provided below the platen.

The conveyance information generation unit 32 is configured by, for example, a rotary encoder. Further, the transport mechanism drive unit 33 is configured by a motor, for example.
In response to an instruction from the control unit 1, the recording medium transport unit 7 sucks and holds the recording medium 51 delivered from the feeding unit on the endless belt by driving a suction fan, and the transport mechanism driving unit 33 further supports the endless belt. Is rotated to convey the recording medium 51 to the downstream side of the conveyance path. At this time, the rotary encoder constituting the conveyance information generation unit 32 generates a pulse signal corresponding to the movement amount of the endless belt (that is, the conveyance amount of the recording medium 51) and notifies the control unit 1 of the pulse signal.

  The recording units 5-1 to 5-n include at least one nozzle row driving units 21-1 to 21-2 m and nozzle rows 22-1 to 22-2 m. Here, the symbols n and m are integers of 2 ≦ n and 2 ≦ m, respectively.

  When the image recording apparatus 1 has a color recording function, as the recording units 5-1 to 5-n, for example, in the order of the conveyance path of the recording medium 51, the K (black) recording unit 5-1, C (cyan). A recording unit 5-2, an M (magenta) recording unit 5-3, and a Y (yellow) recording unit 5-4 are provided.

  In response to an instruction from the control unit 1, the nozzle row driving units 21-1 to 21-2m drive a plurality of nozzles included in the nozzle rows 22-1 to 22-2m to cause ink ejection. In addition, the nozzle array driving units 21-1 to 21-2m apply the nozzle array driving voltages supplied from the nozzle array voltage conversion units 2-1 to 2-m to the nozzle arrays 22-1 to 22-2m.

  In the case where the nozzle arrays 22-1 to 22-2m are alternately arranged, for example, before and after the recording medium 51 in the conveyance direction with respect to the recording units 5-1 to 5-n, the adjacent end portions are included. A portion is arranged so as to overlap when viewed from the conveyance direction. The nozzle arrays 22-1 to 22-2m are formed by deforming, for example, ink stored in a plurality of ink chambers by a piezoelectric member (for example, PZT (lead zirconate titanate) piezoelectric ceramic) provided for each ink chamber. It is configured using a system that discharges by volume change.

  The control unit 1 performs overall control of each component of the image recording device 9, and a storage unit 3 that stores appropriate output voltage values set in the nozzle array voltage conversion units 2-1 to 2-m. At least.

  The control unit 2 includes, for example, an MPU (Micro Processor Unit) having a control function and an arithmetic function, a ROM (Read Only Memory) that stores a control program, and a RAM (Random) that the MPU uses as a work storage area. And a non-volatile memory for storing various setting values related to the control of the image recording apparatus 9.

  For example, the control unit 1 uses, as a trigger, detection information output by the medium detection unit 6 detecting and outputting the leading end of the recording medium 51 to be conveyed, and the number of pulse signals generated by the rotary encoder in the conveyance information generation unit 32 after the trigger. When the cumulative value of the nozzle row coincides with the cumulative value of the number of pulse signals corresponding to the plurality of nozzle formation positions in the nozzle rows 22-1 to 22-2m, the nozzle row driving units 21-1 to 21-2m are controlled. The recording process is performed on the nozzle arrays 22-1 to 22-2m.

  The host apparatus 11 is an external device of the image recording apparatus 9 of the present embodiment, and is connected to the image recording apparatus 1 via, for example, a LAN (Local Area Network). The host apparatus 11 corresponds to a user computer that causes the image recording apparatus 9 of the present invention to perform recording processing, and notifies the image recording apparatus 9 of job information as information relating to recording processing.

Next, the relationship between the position of the nozzle row according to this embodiment and the image recording density will be described.
In the image recording apparatus 9 of the present embodiment, two nozzle rows 22-1 to 22-2m are bonded together to form a bonding head 23-1 to 23-m.

  Here, FIG. 3 and FIG. 4 will be described. 3 and 4 show the state of image recording when image recording is performed with the bonding head used in the image recording apparatus 9 according to the present embodiment. Among these, FIG. 3 shows an example of image recording by the bonding head 23-1 in which the nozzle row 22-1 and the nozzle row 22-2 are bonded at an ideal nozzle pitch. FIG. 4 shows an example of image recording by the bonding head 23-1 in which the nozzle array 22-1 and the nozzle array 22-2 are bonded to each other with an offset from the ideal nozzle pitch.

  Here, the “ideal nozzle pitch” means that the arrangement pitch of each nozzle in the nozzle array 22-1 and each nozzle in the nozzle array 22-2 is 1 as viewed in the sub-scanning direction (recording medium conveyance direction). / 2 It means a state in which the nozzles in the nozzle row 22-2 are arranged at an intermediate point between the nozzles in the nozzle row 22-1 formed at a uniform interval. When the nozzles are arranged in this way, when recording is performed by driving both the nozzle array 22-1 and the nozzle array 22-2, the recording density (formation is formed over the entire area of the recorded image). The density of pixels) becomes uniform.

  In both the bonding heads 23-1 shown in FIGS. 3 and 4, the density of the recorded image when the image recording is performed only with the nozzles of the nozzle row 22-1 and the nozzles of the nozzle row 22-2. It is ideal that the density of the recorded image when the same image is recorded is the same. However, in reality, due to individual differences between the nozzle array 22-1 and the nozzle array 22-2 due to manufacturing variations and the like, the density of the recorded images often does not match even when the same image is recorded. However, this recording density can be adjusted by changing the voltage applied to the nozzle arrays 22-1 and 22-2. Here, Va is a variable range of the applied voltage required for this adjustment.

  Next, FIGS. 5 and 6 will be described. 5 and 6 show how the recording density is adjusted for each nozzle row in the bonding head used in the image recording apparatus 9 according to this embodiment.

  Here, FIG. 5 shows the density in the same direction as the tendency of the change in recording density with respect to each nozzle position between the nozzle array 22-1 and the nozzle array 22-2 constituting the bonding head 23-1. The example in the case of having a gradient is shown. In this case, the recording density can be adjusted to an acceptable level only by adjusting the applied voltage within the range of Va described above.

  On the other hand, FIG. 6 shows the reverse direction as the tendency of the recording density fluctuation for each nozzle position between the nozzle row 22-1 and the nozzle row 22-2 constituting the bonding head 23-1. The example in the case of having a concentration gradient is shown. When the density gradient at the time of image recording is opposite between the nozzle array 22-1 and the nozzle array 22-2 constituting the bonding head 23-1, as shown in FIG. The adjustment of the recording density is insufficient only by adjusting the applied voltage within the range, and it is necessary to adjust the applied voltage in a wider range. Here, let Vb be the variable range of the applied voltage that is further required for this adjustment.

Note that the variable ranges Va and Vb of these applied voltages can be set to relatively small values in a nozzle array manufactured in a stable manufacturing process.
Next, the relationship between the arrangement position and the image recording density when a plurality of bonding heads according to this embodiment are arranged in the sub-scanning direction will be described.

In the image recording apparatus 9 of the present embodiment, a plurality of bonding heads 23-1 to 23-m are arranged side by side in a direction perpendicular to the conveyance direction of the recording medium 51, and the length of the recording medium 51 in the conveyance direction. The line head which has the above length is comprised. The bonding heads 23-1 to 23-m constituting the line head are arranged so that their end portions overlap each other by a predetermined length when viewed in the conveyance direction of the recording medium 51. 7 and FIG. 8 will be described. 7 and 8 show the state of image recording when image recording is performed with the bonding heads 23-1 and 23-2 used in the image recording apparatus 9 according to the present embodiment arranged in the sub-scanning direction. It is shown.

  Here, FIG. 7 shows an example of image recording when two bonding heads 23-1 and 23-2, which are both bonded at an ideal nozzle pitch, are provided. . In this example, when image recording is performed by driving the two bonding heads 23-1 and 23-2 together, the recording density (density of formed pixels) is uniform over the entire area of the recorded image. Become.

  On the other hand, in FIG. 8, of the two bonding heads 23-1 and 23-2, the bonding head 23-2 constituted by the nozzle row 22-3 and the nozzle row 22-4 is an ideal nozzle. An example of image recording when it is pasted out of the pitch is shown. In the case of this example, the recording density of the bonding head 23-1 bonded with an ideal nozzle pitch is higher than the recording density of only the bonding head 23-2. Also for the adjustment for making the recording density uniform, it is effective to change the voltage applied to each of the nozzle arrays 22-1, 22-2, 22-3, and 22-4. Here, the variable range of the applied voltage required for this adjustment is Vc.

  When the nozzle rows are bonded together, the density of the recorded image changes greatly when the pitch of the arrangement of the nozzles is shifted by only a few micrometers from the ideal nozzle pitch. For this reason, in order to improve the bonding accuracy and suppress the density difference, extremely high accuracy is required for processing, bonding position adjustment, and assembly, which is not realistic from the viewpoint of manufacturing cost. Therefore, when image recording is performed with a plurality of bonding heads arranged in the sub-scanning direction, the recording density between the bonding heads is adjusted by adjusting the voltage applied to the nozzle row driving unit described above. There is a need. Note that the adjustment range Vc of the applied voltage for adjusting the recording density needs to be much wider than the adjustment ranges Va and Vb described above.

Next, adjustment of the recording density for each bonding head when performing image recording by arranging a plurality of bonding heads according to the present embodiment in the sub-scanning direction will be described.
9 and 10 both show the positions of the nozzles and the recording density when the bonding heads 23-1 and 23-2 used in the image recording apparatus 9 according to the present embodiment are arranged in the sub-scanning direction. An example of the relationship is shown. Here, FIG. 9 shows the relationship between each nozzle position and the recording density before adjusting the recording density, and FIG. 10 shows the relationship between each nozzle position and the recording density after adjusting the recording density. .

  When both the bonding heads 23-1 and 23-2 have a density gradient as a tendency of the recording density fluctuation with respect to the nozzle position, the adjustment of the recording density is performed by the bonding heads 23-1 and 23-2. When the image recording is performed only for each of the recording heads, as shown in FIG. 9, a discontinuous density region is generated at the boundary between the bonding head 23-1 and the bonding head 23-2. There is. A recorded image in which such a region occurs gives an unnatural impression. Therefore, the voltage applied to the bonding heads 23-1 and 23-2 is adjusted, and the recording density is adjusted at the boundary between the bonding head 23-1 and the bonding head 23-2 as shown in FIG. It needs to be continuous. Here, the variable range of the applied voltage required for this adjustment is Vd.

  When a full-line image recording apparatus is configured by arranging a plurality of bonding heads in the sub-scanning direction, the above-described adjustment for making the recording density continuous needs to be performed for each boundary between the plurality of bonding heads. Therefore, the variable range Vd of the applied voltage described above needs to be much wider than the adjustment ranges Va and Vb described above.

To summarize the above description, in order to obtain a uniform image density with a bonding head in which a plurality of nozzle rows are bonded, the variable range V1 of the voltage applied to the bonding head is as follows:
V1 = Va + Vb
Is required.

Further, when a full-line type image recording apparatus is configured by arranging a plurality of bonding heads in the sub-scanning direction, in order to obtain a uniform image density, a variable range V2 of the voltage applied to the bonding head is used. ,
V2 = Vc + Vd
Is required.

Here, the range of the voltage variable ranges Va and Vb mainly determined by the nozzle row manufacturing process may be narrow, while the voltage variable range Vc and Vd range in which various factors other than the nozzle row manufacturing process are involved is wide. Things are needed. Therefore, between the variable range V1 and V2 of the voltage applied to the nozzle row,
Vl << V2
It will have the relationship.

Next, the configuration of the nozzle array voltage conversion units 2-1 to 2-m according to the present embodiment will be described.
FIG. 11 shows a first example of the configuration of the nozzle array voltage conversion units 2-1 to 2-m according to the present embodiment. FIG. 11 shows only the configuration of the nozzle row voltage conversion units 2-1 and 2-2, but the nozzle row voltage conversion units 2-3 to 2-m also include the nozzle row voltage conversion unit 2-1 and It is the same structure as 2-2.

  In this first example, one switching regulator 2-1-1 and 2-2-1 are provided for each of the bonding heads 23-1 and 23-2, and the bonding heads 23-1 and 23-2 are provided. One dropper regulator 2-2-1-1 to 2-2-2-2 is provided for each of the nozzle rows 22-1 to 22-4 constituting the nozzle row voltage converter 2-1 and 2-2 is configured.

  Here, the switching regulators 2-1-1 and 2-2-1 convert (for example, step-down) the output voltage of the main power supply 8 that supplies power for driving all of the nozzle arrays 22-1 to 22-4. To do. The dropper regulators 2-1-2-1 to 2-2-2-2 are for stepping down the output voltages of the switching regulators 2-1-1 and 2-2-1. Among these, the dropper regulators 2-2-1-1 and 2-1-2-2 individually step down the output voltage of the switching regulator 2-1-1 and corresponding nozzle arrays 22-1 and 22-2. To be applied. The dropper regulators 2-2-1 and 2-2-2 individually step down the output voltage of the switching regulator 2-2-1 and apply it to the corresponding nozzle rows 22-3 and 22-4. To do.

  In the configuration of FIG. 11, adjustment of the voltage applied to each of the nozzle arrays 22-1 to 22-4 is performed with respect to, for example, the dropper regulators 2-1-2-1 to 2-2-2-2. That is, the dropper regulators 2-1-2-1 to 2-2-2-2 provide the function of adjusting the output voltage over the variable range of V1 and V2 described above. And the information which shows the appropriate voltage value after this adjustment is memorize | stored in the memory | storage part 3 in the control part 1. FIG. When the image recording apparatus 9 according to the present embodiment performs an image recording operation, the control unit 1 controls the dropper regulators 2-2-1-1 to 2-2-2-2 based on the stored information. An appropriate voltage value is applied to each of the nozzle rows 22-1 to 22-4.

  Since the image recording apparatus 9 includes the nozzle array voltage conversion units 2-1 to 2-m having the configuration according to the first example illustrated in FIG. 11, the number of switching regulators having a complicated circuit configuration and high cost can be reduced. This can be reduced compared to the case where one switching regulator is provided for each of the nozzle arrays 22-1 to 22-2m. Therefore, according to the image recording apparatus 9 according to the present embodiment, the circuit configuration of the nozzle row driving power source is simplified and the cost can be reduced.

  FIG. 12 shows a second example of the configuration of the nozzle array voltage conversion units 2-1 to 2-m according to the present embodiment. FIG. 12 shows only the configuration of the nozzle row voltage conversion units 2-1 and 2-2, but the nozzle row voltage conversion units 2-3 to 2-m also include the nozzle row voltage conversion unit 2-1 and It is the same structure as 2-2.

  In this second example, the switching regulators 2-1-1 and 2-2-1 and the dropper regulators 2-1-2 and 2-2-2 are respectively set to the bonding heads 23-1 and 23-2. Further, regulators for applying voltages to the nozzle arrays 22-1 to 22-4 are provided, switching regulators 2-1-1 and 2-2-1, and dropper regulators 2-1-2 and 2-2. Nozzle switch voltage conversion units 2-1 and 2-2 are provided by providing one changeover switch 2-1-3 and 2-2-3, respectively.

  Here, each of the switching regulators 2-1-1 and 2-2-1 converts the output voltage of the main power supply 8 that supplies power for driving all of the nozzle arrays 22-1 to 22-4 ( For example, the pressure is reduced. The dropper regulators 2-1-2 and 2-2-2 step down the output voltages of the switching regulators 2-1-1 and 2-2-1, respectively.

  The change-over switch 2-1-3 is a regulator that applies a voltage to each of the nozzle rows 22-1 and 22-2 constituting the bonding head 23-1 and a switching regulator 2-1-1 and a dropper. Switching between the regulator 2-1-2. Therefore, when the output voltage of the switching regulator 2-1-1 is applied to either the nozzle row 22-1 or the nozzle row 22-2, the output voltage of the dropper regulator 2-1-2 is It is applied to the one where the output voltage of the switching regulator 2-1-1 is not applied among the 22-1 and the nozzle array 22-2.

  The change-over switch 2-2-3 is a switching regulator 2-2-1 that applies a voltage to each of the nozzle rows 22-3 and 22-4 constituting the bonding head 23-2. And the dropper regulator 2-2-2. Therefore, when the output voltage of the switching regulator 2-2-1 is applied to either the nozzle row 22-3 or the nozzle row 22-4, the output voltage of the dropper regulator 2-2-2 is It is applied to the one to which the output voltage of the switching regulator 2-2-1 is not applied among 22-3 and the nozzle row 22-4.

  In the configuration of FIG. 12, the adjustment of the voltage applied to each of the nozzle rows 22-1 to 22-4 is performed by switching regulators 2-1-1 and 2-2-1 and dropper regulators 2-1-2 and 2-2. Perform for both 2-2. Here, for example, the switching regulators 2-1-1 and 2-2-1 provide the function of adjusting the output voltage over the above-described variable range of V1, and the above-described variable range of V2 is narrower than V1. Dropper regulators 2-1-2 and 2-2-2 provide an output voltage adjustment function. Then, information indicating the adjusted appropriate voltage value and switching information of the changeover switches 2-1-3 and 2-1-4 are stored in the storage unit 3 in the control unit 1. When the image recording apparatus 9 according to the present embodiment performs an image recording operation, the control unit 1 performs switching regulators 2-1-1 and 2-2-1 and a dropper regulator 2-1-2 based on the stored information. And 2-2-2 and the selector switches 2-1-3 and 2-1-4 are controlled to apply appropriate voltage values to each of the nozzle arrays 22-1 to 22-4.

  Since the image recording apparatus 9 includes the nozzle array voltage conversion units 2-1 to 2-m having the configuration according to the second example illustrated in FIG. 12, the number of switching regulators having a complicated circuit configuration and high cost can be reduced. This can be reduced compared to the case where one switching regulator is provided for each of the nozzle arrays 22-1 to 22-2m. Therefore, according to the image recording apparatus 9 according to the present embodiment, the circuit configuration of the nozzle row driving power source is simplified and the cost can be reduced. In addition, since the nozzle row voltage converters 2-1 to 2-m having the configuration according to the second example shown in FIG. 12 have a smaller number of dropper regulators than the first example shown in FIG. The circuit configuration of the nozzle row driving power supply is further simplified, and the cost can be further reduced.

  The embodiments of the present invention are not limited to the above-described embodiments, and various improvements and changes can be made without departing from the scope of the present invention.

1 is a diagram illustrating a conceptual block configuration of an inkjet image recording apparatus according to an embodiment of the present invention. 1 is a diagram schematically illustrating an arrangement example of an inkjet image recording apparatus according to an embodiment of the present invention. FIG. 6 is a diagram (part 1) illustrating a state of image recording when image recording is performed with a bonding head. FIG. 6 is a diagram (part 2) illustrating a state of image recording when image recording is performed with a bonding head. FIG. 6 is a diagram (No. 1) showing how recording density is adjusted for each nozzle row in a bonding head; FIG. 10 is a (second) diagram illustrating how recording density is adjusted for each nozzle row in the bonding head; FIG. 6 is a diagram (part 1) illustrating a state of image recording when two bonding heads are arranged in the sub-scanning direction and image recording is performed. FIG. 10 is a diagram (part 2) illustrating a state of image recording when two bonding heads are arranged in the sub-scanning direction and image recording is performed. FIG. 6 is a diagram (part 1) illustrating an example of a relationship between each nozzle position and recording density when two bonding heads are arranged in the sub-scanning direction. FIG. 10 is a diagram (part 2) illustrating an example of a relationship between each nozzle position and recording density when two bonding heads are arranged in the sub-scanning direction. It is a figure which shows the 1st example of a structure of the nozzle row voltage conversion part which concerns on this embodiment. It is a figure which shows the 2nd example of a structure of the nozzle row voltage conversion part which concerns on this embodiment. It is a figure which shows the structure of a bonding head. It is a figure which shows the structure of the recording head comprised by arrange | positioning and arrange | positioning the edge part of a bonding head. It is a figure which shows the structure of the line head comprised by arrange | positioning multiple bonding heads. It is a figure explaining the problem which the recording head which arrange | positioned and comprised the several bonding head has. It is a figure which shows an example of the solution of the problem of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control part 2,2-1 thru | or 2-m Nozzle row voltage conversion part 2-1-1, 2-2-1 Switching regulator 2-1-2, 2-2-2
2-1-2-1 to 2-2-2-2 dropper regulator 2-1-3, 2-2-3 changeover switch 3 storage unit 4 plain memory 5-1 to 5-n recording unit 6 medium detection unit 7 Recording medium transport unit 8 Main power supply 11 Host device 21-1 to 21-2m Nozzle row drive unit 22-1 to 22-2m Nozzle row 23-1 to 23-m Bonding head 31 Transport member 32 Transport information generation unit 33 Transport Mechanism drive unit 41a Driven roller 41b Drive roller 51 Recording medium

Claims (7)

In an inkjet recording apparatus having a plurality of nozzle rows formed by arranging a plurality of nozzles for discharging ink in a straight line,
A plurality of dropper regulators associated one by one for each nozzle row;
A switching regulator that converts an output voltage of a power supply that supplies power for driving all of the nozzle rows and outputs the converted voltage to the dropper regulator;
Comprising at least a nozzle row voltage converter comprising:
The ink jet recording apparatus, wherein the dropper regulator steps down and applies a voltage output from the switching regulator to a nozzle row associated with the dropper regulator.   The inkjet recording apparatus according to claim 1, wherein the nozzle rows are bonded two by two to form a plurality of bonded heads.   A plurality of the bonding heads are arranged side by side in a direction perpendicular to the conveyance direction of the recording medium, and constitute a line head having a length equal to or longer than the length in the conveyance direction of the recording medium. The inkjet recording apparatus according to claim 2.   4. The inkjet according to claim 3, wherein the laminating head constituting the line head is disposed so that an end thereof overlaps with a predetermined length when viewed in the transport direction. Recording device. In an inkjet recording apparatus having a plurality of nozzle rows formed by arranging a plurality of nozzles for discharging ink in a straight line,
The nozzle row is laminated two by two to form a plurality of pasting heads,
A plurality of dropper regulators associated with each of the bonding heads;
A plurality of switching regulators associated with each of the bonding heads;
Comprising at least a nozzle row voltage converter comprising:
The switching regulator converts an output voltage of a power supply that supplies electric power for driving all of the nozzle rows, and includes two nozzle rows that constitute a bonding head associated with the switching regulator. The voltage after the conversion is applied to one of the
The dropper regulator steps down and applies the converted voltage to the nozzle row to which the switching regulator does not apply the converted voltage, of the two nozzle rows associated with the dropper regulator. An ink jet recording apparatus.   A plurality of the bonding heads are arranged side by side in a direction perpendicular to the conveyance direction of the recording medium, and constitute a line head having a length equal to or longer than the length in the conveyance direction of the recording medium. An ink jet recording apparatus according to claim 5.   The inkjet head according to claim 6, wherein the bonding head constituting the line head is disposed such that an end portion thereof overlaps with a predetermined length when viewed in the transport direction. Recording device.