JP2006212791A - Inkjet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable improvement of a nozzle interval precision between head units, and also to enable easy replacement of the head units without the nozzle interval precision damaged. <P>SOLUTION: A recording head HD has the constitution in which the head units H1-H4 with a plurality of nozzles formed and arranged therein are set side by side detachably at a supporting frame SW which supports the head units H1-H4, along a unit arrangement direction that intersects a transfer direction so that dot trains can be formed to align at predetermined intervals along a main scanning direction Y orthogonal to the transfer direction of a recording medium. Each of the head units H1-H4 has projecting parts with projection amounts adjusted to be a predetermined size from predetermined nozzles at the outside of unit bodies of the head units H1-H4 in a plan view. The projecting parts are arranged to connect positioning reference parts set at the supporting frame SW. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus, and more particularly to a recording head that performs recording by ejecting ink droplets onto a recording medium.

  In recent years, in an ink jet recording apparatus that performs recording on a recording medium by ejecting ink droplets from nozzles, in order to increase the recording speed, a large number of nozzles are arranged in a direction crossing the recording medium conveyance direction. An ink jet recording apparatus (hereinafter referred to as a line type ink jet recording apparatus) including a line type recording head (hereinafter referred to as a line head) arranged over a distance greater than a width has been put into practical use.

In this line head, conventionally, a configuration is known in which a plurality of head units constituting the recording width are detachably disposed on a head base (for example, see Patent Document 1).
JP-A-9-1789 (page 3, FIG. 1)

In the configuration of Patent Document 1, the position of each head unit with respect to the head base is determined by fitting a slide groove, which is a tenon groove, into a tenon provided on the head base.
In general, when a line head is configured by arranging a plurality of head units, each head unit has a recording resolution of, for example, 360 dpi so that the nozzle interval between the head units is within an allowable range of about ± 5 μm. Strict positional accuracy is required. If this nozzle interval deviates from the allowable range, the interval between dots formed by the ink droplets ejected from the nozzle becomes wider than the other parts at the boundary of recording between head units, Banding that gets narrower will occur. Further, the allowable range in the nozzle interval becomes narrower as the recording resolution becomes higher.

That is, in the configuration of Patent Document 1, there are many factors such as the slide groove shape accuracy, slide groove dimensional accuracy, and slide groove position accuracy with respect to the nozzle, so that the nozzle spacing accuracy between the head units is improved. There is an unsolved problem that is difficult.
The present invention has been made to solve the above-described problems, and can improve the nozzle interval accuracy between the head units and easily replace the head unit without impairing the nozzle interval accuracy. An object of the present invention is to provide an ink jet recording apparatus capable of performing the above.

  A first aspect of the invention is an ink jet recording apparatus comprising: a recording medium conveying unit that conveys a recording medium; and a recording head that performs recording by ejecting ink droplets from nozzles onto the recording medium conveyed by the recording medium conveying unit. The recording head can form a dot row that aligns a plurality of head units in which a plurality of the nozzles are arrayed at a predetermined interval along a main scanning direction orthogonal to the conveyance direction of the recording medium. A plurality of head units are arranged in a support frame that supports the plurality of head units along a unit arrangement direction that intersects the transport direction so as to be detachable. A protrusion provided on the support frame, the protrusion having an amount of protrusion adjusted to a predetermined size from the predetermined nozzle on the outside of the unit body; Characterized in that it is disposed to abut against the semi-section.

According to the first aspect of the invention, the head unit is provided with a protruding portion whose protruding amount is adjusted to a predetermined dimension from a predetermined nozzle, and the protruding portion can be attached to and detached from the positioning reference portion. It is arrange | positioned at the support frame.
Therefore, it is possible to reduce the factor that affects the nozzle interval accuracy, and it is possible to improve the nozzle interval accuracy. In addition, when replacing the head unit, it is possible to ensure good nozzle spacing accuracy by simply bringing the protruding portion into contact with the positioning reference portion, and it is possible to replace the head unit easily and accurately.

  According to a second invention, in the first invention, the protrusion amount is formed by decentering a head portion having an outer periphery larger than the shaft portion at one end portion of the shaft portion in plan view with respect to the shaft portion. A core member is disposed on the unit body so that the head protrudes outside the unit body in a plan view and is rotatable about the shaft, and the head protrudes from the unit body. The amount is adjusted to be a predetermined dimension from the predetermined nozzle.

In the second aspect of the invention, if the eccentric member provided in the unit body is rotated, the protrusion amount of the head can be reduced within a range twice the eccentric amount of the shaft portion of the eccentric member and the head. It becomes possible to adjust.
Therefore, it is possible to improve the nozzle interval accuracy by a simple method of rotating the eccentric member.
According to a third aspect, in the second aspect, the unit body is provided with at least three eccentric members so that the protruding amounts of the eccentric members can be adjusted. And

An embodiment of the present invention will be described with reference to the drawings, taking a line type ink jet recording apparatus that performs black color recording as an example.
As shown in FIG. 1A, which is a plan view, and FIG. 1B, which is a front view, an ink jet recording apparatus 1 according to an embodiment of the present invention includes a gate roller GR, a paper transport unit CV, and a recording head HD. And. In FIG. 1, the X direction indicates the conveyance direction of the recording paper P, and the Y direction indicates a direction orthogonal to the X direction.

Further, as shown in FIG. 2 which is a block diagram, the inkjet recording apparatus 1 has a recording information storage for storing recording information from a paper feeding unit KS, a transport unit driving motor Mo, a paper discharging unit EJ, and an external device. Part BF.
Here, the detail of each said structure is demonstrated.
As shown in FIG. 3 which is a plan view, the recording head HD is configured to include four head units H1 to H4 and a support frame SW that supports the head units H1 to H4.

These head units H1 to H4 are arranged with two head units H1 and H2 aligned at a predetermined interval in the Y direction, and the other two head units H3 on the downstream side in the X direction of these head units H1 and H2. And H4 are arranged at predetermined intervals in the Y direction, and are arranged so as to be alternately arranged in the Y direction with the head units H1 and H2.
As shown in FIG. 4A, which is a plan view, each of the head units H1 to H4 includes a unit body UB and slotted eccentric screws HS1 to HS3. As shown in FIG. 4B, which is a side view, the unit body UB has arm portions AM formed on the upper and lower side surfaces as viewed in this figure. The eccentric machine screws HS1 to HS3 are assigned the same reference numerals for the sake of convenience, but are the same.

As shown in FIG. 4C, which is a bottom view, these arm portions AM are formed with screw holes NA into which the eccentric machine screws HS1 to HS3 are fitted, and a cross-recessed machine screw described later. A screw insertion hole FH to be inserted is formed.
Here, the eccentric machine screws HS1 to HS3 are provided to regulate the position of the unit body UB with respect to a support frame SW described later, and are bonded to the arm portion AM after the rotation position described later is adjusted. Fixed.

  Further, as shown in FIG. 4C, the head units H1 to H4 move the nozzles NZ from which ink droplets are ejected in the Y direction at a predetermined interval CL over a distance KH, where n (n is 2 or more). (Integer) arrangement. The arrangement distance KH of the nozzles NZ is a recording width in each of the head units H1 to H4. In addition, as these head units H1 to H4, a head unit that applies pressure to ink by a piezoelectric element, a heating element or the like and ejects ink droplets from the nozzle NZ can be employed.

Further, in FIG. 4C, the size of the nozzle NZ is exaggerated for easy understanding of the configuration. Further, different symbols NZ1 to NZn are given to the n nozzles NZ, and in the present specification, for convenience of explanation, the symbols NZ and NZ1 to NZn are properly used.
As shown in FIG. 5A, which is a plan view of the support frame SW, unit disposition tanks HT1 to HT4 partitioned by side walls are formed for each head unit H1 to H4. A head unit insertion opening OH for inserting the head units H1 to H4 and a screw hole NH for stopping a cross-recessed machine screw CS, which will be described later, are formed on the bottom surfaces of the unit arranging tanks HT1 to HT4.

As shown in FIG. 5B, which is a cross-sectional view taken along the line BB in FIG. 5A, the head unit insertion opening OH is formed on the inner wall WY extending in the Y direction as seen in this figure. Are formed along.
Each inner wall WY is formed with high vertical accuracy with respect to the inner wall WX extending along the X direction for each of the unit placement tanks HT1 to HT4 as seen in FIG. Furthermore, the inner side wall WY between the unit arrangement tanks HT1 and HT2 is located on a straight line extending along the Y direction. Similarly, the inner side wall WY between the unit arrangement tanks HT3 and HT4 is located on a straight line extending along the Y direction.

Further, the inner side wall WX is formed with high accuracy at a predetermined interval in the Y direction between the unit arrangement tanks HT1 to HT4.
Here, as shown in FIG. 3, each of the head units H1 to H4 is inserted into the head unit insertion opening OH of the support frame SW, and the eccentric small screws HS1 to HS3 are applied to the inner wall WX and the inner wall WY. The positions in the X direction and the Y direction are determined by contact. In each head unit H1 to H4, the arm part AM is fixed to the support frame SW by a cross-recessed machine screw CS through a screw insertion hole FH formed in the two arm parts AM.

  Here, as shown in FIG. 6 which is a bottom view, the recording head HD is arranged such that the head units H1 to H4 are aligned at a predetermined interval in the Y direction. That is, the head units H1 to H4 are each provided with a predetermined distance CL between the nozzles NZn of the head unit H1 and the nozzles NZ1 of the head unit H3 by the eccentric machine screws HS1 to HS3, respectively. The arrangement positions are determined such that the distance between the nozzles NZ1 of H2 is a predetermined distance CL, and the distance between the nozzles NZn of the head unit H2 and the nozzle NZ1 of the head unit H4 is a predetermined distance CL.

Therefore, when the head units H1 to H4 are aligned on the straight line in the Y direction, all the nozzles NZ of the head units H1 to H4 are aligned at a predetermined interval CL over the distance KR. This distance KR is a Y-direction recording area in the inkjet recording apparatus 1.
As shown in FIG. 1A, the recording head HD having the above configuration has the nozzle NZ on the recording paper P such that the recording area KR straddles the width of the recording paper P in the Y direction on the paper transport unit CV. Further, as shown in FIG. 1B, the nozzle surface and the recording surface PP of the recording paper P are arranged so as to be kept at a predetermined interval.

In addition, as shown in FIG. 2, the recording head HD has its head units H1 to H4 individually controlled by a head control unit HDD that receives a recording command from the CPU, and a recording area based on recording information from an external device. Recording is performed by selectively ejecting ink droplets from the nozzles NZ constituting the KR.
As shown in FIG. 1A, the paper transport unit CV is disposed on the upstream side in the X direction of the drive roller DS and the drive roller DS to which power is transmitted from the transport unit drive motor Mo. A driven roller FS, and a driving belt DS and a conveyor belt V that runs over the driven roller FS.

Here, although not shown, the drive roller DS and the driven roller FS are rotatably held in the housing by a bearing.
Further, although not shown, the driven roller FS is applied with a force in the upstream direction in the X direction in order to apply tension so as not to loosen the conveying belt V that is passed between the driven roller FS and the driving roller DS.

  As shown in FIG. 2, the conveyance unit drive motor Mo is driven by a motor control unit MD that receives a conveyance unit drive command from the CPU, and drives the paper conveyance unit CV. Then, the paper transport unit CV transports the recording paper P placed on the transport belt V by rotating the transport belt V counterclockwise as viewed in FIG. 1B by the power of the transport unit drive motor Mo. It is conveyed in the X direction which is the direction.

As shown in FIG. 2, the operation of the paper feeding unit KS is controlled by a paper feeding control unit KSD that receives a paper feeding command from the CPU, and recording is performed from a paper cassette, a paper tray, etc. (not shown) in which the recording paper P is stored. The paper P is supplied one by one to a gate roller GR described later.
As shown in FIGS. 1A and 1B, the gate roller GR is provided on the upstream side in the X direction of the paper transport unit CV, and includes a pair of rollers that rotate while contacting the outer periphery. Yes. The gate roller GR is skew-corrected to correct the inclination of the recording paper P with respect to the X direction and the positional deviation in the Y direction when the recording paper P is supplied by the paper supply unit KS so as to abut between the pair of rollers. I do. As shown in FIG. 2, the gate roller GR is driven by a gate roller control unit GRD that receives a paper supply command from the CPU at a predetermined timing, and the recording paper P subjected to skew correction is fed to a paper transport unit. Supply to CV.

The paper discharge unit EJ shown in FIG. 2 is disposed on the downstream side in the X direction of the paper conveyance unit CV. The drive is controlled by the paper discharge control unit EJD that has received a paper discharge command from the CPU and is conveyed by the conveyance belt V. The discharged recording paper P is discharged out of the inkjet recording apparatus 1.
As shown in FIGS. 1A and 1B, the ink jet recording apparatus 1 having the above-described configuration records on a recording sheet P that is placed on the transport belt V and transported in the X direction under the recording head HD. Recording is performed by ejecting ink droplets toward the surface PP. That is, the ink jet recording apparatus 1 completes recording without moving the recording head HD by ejecting ink droplets from the nozzles NZ onto the recording paper P that is continuously or intermittently moved under the recording head HD by the conveyance belt V. To do.

The recording paper P or the conveyance belt V is charged so that the recording paper P does not deviate from the position on the conveyance belt V, or an opening is formed on the surface of the conveyance belt V on which the recording paper P is placed. It is desirable that the recording paper P is adsorbed to the conveying belt V by forming and sucking air using a suction fan.
Here, the manufacturing method of each head unit H1-H4 is demonstrated.

This manufacturing method adjusts the rotational position of the eccentric small screws HS1 to HS3 in the head units H1 to H4, and the jig positioning step for aligning the rotational position adjusting jig and the optical axis of the optical microscope, which will be described later. There are roughly divided into a rotation position adjustment process and an adhesion process in which the eccentric machine screws HS1 to HS3 are adhered to the arm portion AM.
Here, first, the jigs and tools used in the rotation position adjustment process and the jigs and tools used in the jig position adjustment process will be described in this order, and then the jig position adjustment process and the rotation position adjustment process. The bonding process will be described in this order to facilitate understanding of the manufacturing method.

  In the rotational position adjusting step, the unit body UB is placed on the rotational position adjusting jig TL with the eccentric machine screws HS1 to HS3 fitted in the screw holes NA as shown in FIG. As shown in FIG. 7B, the eccentric machine screws HS1 to HS3 are rotated while grasping the position of the nozzle NZ with the optical microscopes MS1 and MS2, and the position of the unit body UB with respect to the rotational position adjusting jig TL is determined. It is a process to decide.

Here, as shown in FIG. 8A, which is a plan view, the rotational position adjusting jig TL is a front view with an opening OP into which the unit body UB is inserted on the bottom surface BM. As shown in FIG. 8 (b), the inner side walls TY and TX with which the eccentric machine screws HS1 to HS3 abut are formed to extend upward from the bottom surface BM as seen in this figure.
The rotational position adjusting jig TL is formed by a machine tool such as a surface grinding machine, and the bottom surface BM and the inner side walls TY and TX are machined with high planar accuracy and mutual vertical accuracy.

Then, when the unit body UB is inserted into the opening OP of the rotational position adjusting jig TL, as shown in FIG. 7B, the arm part AM of the unit body UB is supported by the bottom surface BM. In addition, the thickness of the bottom surface BM is set to such a thickness that the nozzle surface, which is the surface on which the nozzle NZ of the unit body UB is formed, does not protrude outward from the bottom surface BM.
Further, each of the eccentric machine screws HS1 to HS3 has a shaft portion with the center of the head TB having a radius of a distance R as shown in FIG. 9A which is a detailed view of the B portion in FIG. It is biased at a distance K from the center of JK. In the state shown in FIG. 9A, the distance R from the inner wall TX of the rotational position adjusting jig TL to the center of the shaft portion JK is the distance R.

When each of the eccentric small screws HS1 to HS3 is rotated 90 degrees counterclockwise as viewed in this figure from the state shown in FIG. 9A, as shown in FIG. The distance to the center of JK is the distance (R−K).
Further, when each of the eccentric machine screws HS1 to HS3 is rotated 90 degrees clockwise from the state shown in FIG. 9A, as shown in FIG. 9C, as shown in FIG. The distance to the center of the part JK is the distance (R + K).

That is, each of the eccentric small screws HS1 to HS3 is configured to be able to adjust the position of the unit body UB with respect to the rotational position adjusting jig TL within a range of distance (2 × K).
Next, jigs and tools used in the jig positioning process will be described.
This jig alignment process is a process in which the positions of the rotational position adjustment jig TL and the optical axes of the optical microscopes MS1 and MS2 are aligned using a reference scale.

The reference scale SC is processed and formed by a machine tool such as a surface grinding machine, and as shown in FIG. 10A which is a plan view and FIG. 10B which is a front view, a scale plate BD having a predetermined thickness. The back surface RP and the side surfaces PY and PX are machined with high accuracy in their respective plane accuracy and mutual vertical accuracy.
Further, on the back surface RP of the scale plate BD, as shown in FIG. 10C, which is a bottom view, a scale SC1 parallel to the side surface PY and a scale SC2 parallel to the side surface PX have a distance LX and a side surface from the side surface PY. It is engraved so as to intersect at a distance LY from PX.

The length of the scale SC1 may be the same as the length of the recording width KH of the head units H1 to H4 from the intersection CP with the scale SC2 to the end on the side PX side, and is formed with high accuracy. It does not have to be.
Next, the flow of the jig positioning process will be described.
In this jig / tool positioning step, first, the reference scale SC is brought into contact with the inner wall TY of the rotational position adjusting jig TL as shown in FIG. Then, the side surface PX is brought into contact with the inner side wall TX and placed on the rotational position adjusting jig TL. At this time, the scales SC1 and SC2 of the reference scale SC are visually recognized through the opening OP as shown in FIG.

Next, with the scales SC1 and SC2 visible, the optical axes of the optical microscopes MS1 and MS2 are aligned as shown in FIG. At this time, the optical axis of the optical microscope MS1 is aligned with the intersection CP of the scales SC1 and SC2, and the optical axis of the optical microscope MS2 is aligned with the scale SC1 in the vicinity of the end on the side surface PX side of the scale SC1.
Next, the flow of the rotation position adjustment process will be described.

In this rotational position adjustment process, the unit body UB is eccentric with the eccentric small screws HS1 to HS3 fitted in the screw holes NA as shown in FIGS. 7 (a) and 7 (b). The heads TB of the machine screws HS1 to HS3 are brought into contact with the inner side walls TY and TX and placed on the rotational position adjusting jig TL.
Next, while grasping the position of the nozzle NZ with the optical microscopes MS1 and MS2, the eccentric machine screws HS1 to HS3 are rotated while maintaining the contact between the head TB and the inner walls TY and TX, and the unit body UB The position with respect to the rotational position adjustment jig TL is adjusted.

  Here, as shown in FIGS. 12A and 12B, the optical microscopes MS1 and MS2 are views showing the visual field visually recognized through the horizontal lines HL1 and HL1 extending in the horizontal direction as seen in these drawings. Cross lines composed of HL2 and vertical lines PL1 and PL2 extending in the vertical direction are formed in the respective visual fields. In these FIGS. 12A and 12B, the horizontal lines HL1 and HL2 and the vertical lines PL1 and PL2 are indicated by alternate long and short dash lines.

And when rotating each eccentric machine screw HS1 to HS3, as shown in FIG. 12A, the intersection of the horizontal line HL1 and the vertical line PL1 in the optical microscope MS1 is aligned with the center of the nozzle NZ1. Each eccentric machine screw HS1 to HS3 is rotated.
Next, each eccentricity is set so that the intersection of the horizontal line HL2 and the vertical line PL2 in the optical microscope MS2 is located on a line connecting the center of the nozzle NZn and the center of the nozzle NZ1, as shown in FIG. The small screws HS1 to HS3 are rotated.

Here, in the optical microscope MS2, the intersection of the horizontal line HL2 and the vertical line PL2 in the optical microscope MS2 is not aligned with the center of the nozzle NZn but on the line connecting the center of the nozzle NZn and the center of the nozzle NZ1. This is because it is sufficient to know the inclination of the UB with respect to the horizontal line HL2.
That is, the position of the unit body UB with respect to the rotational position adjustment jig TL is adjusted by aligning the cross point of the optical microscope MS1 with the center position of the nozzle NZ1, and the center of the nozzle NZn and the center of the nozzle NZ1 are connected. The inclination of the unit body UB with respect to the rotational position adjusting jig TL is adjusted by aligning the crossing point of the optical microscope MS2 on the line.

After adjusting the position and inclination of the unit body UB with respect to the rotational position adjusting jig TL in the rotational position adjusting step, when the eccentric machine screws HS1 to HS3 are bonded to the arm part AM in the bonding step, the head units H1 to H1 are bonded. H4 is completed.
In the present embodiment, the inner side walls WY and WX correspond to the positioning reference portion, and the eccentric machine screws HS1 to HS3 correspond to the eccentric member.

In the ink jet recording apparatus according to the present embodiment, the head units H1 to H4 are arranged such that the head units TB of the eccentric small screws HS1 to HS3 touch the inner side walls TY and TX of the rotational position adjusting jig TL. When placed on the rotation position adjustment jig TL in a contact state, the position of the nozzle NZ with respect to the rotation position adjustment jig TL has high accuracy.
The head units H1 to H4 have the eccentric machine screws HS1 to HS3 brought into contact with the inner wall WX and the inner wall WY of the support frame SW, and the arm portion AM is attached to the support frame SW by the cross-recessed machine screw CS. It is fixed.

  Therefore, for example, when one of the head units H1 to H4 breaks down and is replaced with a new head unit, the eccentric head screws HS1 to HS3 of the new head unit are replaced with the inner side wall WX and the inner side wall WY of the support frame SW. All the head units H1 to H4 including the new head unit can be easily and accurately arranged by simply contacting and fixing the arm portion AM to the support frame SW with the cross-recessed machine screw CS. .

In the present embodiment, the case where the eccentric machine screws HS1 to HS3 have a circular head TB in plan view has been described as an example. However, the shape of the head TB is not limited to this, and as shown in FIG. Further, it may be polygonal in plan view.
In this case, the amount of rotation of the eccentric machine screws HS1 to HS3 is adjusted so that each periphery constituting the polygon comes into contact with the inner wall WX and the inner wall WY of the support frame SW. Accordingly, the heads TB of the eccentric small screws HS1 to HS3 stably come into contact with the inner side wall WX and the inner side wall WY of the support frame SW, so that the positional stability of the head units H1 to H4 with respect to the support frame SW is increased. It becomes possible.

Further, the number of corners of the polygon forming the head TB of the eccentric machine screws HS1 to HS3 can be any value of 3 or more.
In this embodiment, the line type ink jet recording apparatus that performs black color recording has been described as an example. However, the present invention is not limited to this, and a recording head HD that performs magenta, cyan, and yellow color recording is added. The type can be configured to include any type of recording head HD such as six types including light cyan and light magenta, and the configuration of the head units H1 to H4 and the support frame SW can be changed accordingly. do it.

In this embodiment, the recording head HD is arranged with the arrangement direction of the nozzles NZ oriented in the Y direction. However, the present invention is not limited to this, and the recording head HD is arranged in an arbitrary direction intersecting the X direction. You may make it do. In this case, the nozzle pitch viewed from the conveyance direction of the recording paper P can be set short, and the recording resolution in the Y direction can be increased.
Further, the recording medium is not limited to the recording paper P, and any recording medium can be applied as long as ink droplets can adhere to form dots.

  Further, in the present embodiment, the belt conveyance in which the recording paper P is placed on the conveyance belt V and conveyed is adopted. However, the present invention is not limited to this, and the recording paper P is sandwiched between a pair of rollers rotating on the outer periphery. An arbitrary conveyance form such as a roller conveyance to be conveyed and a drum conveyance in which the outer periphery is fixed to the outer peripheral surface of the rotating drum with the outer periphery facing the nozzle surface of the recording head HD can be adopted.

1 is an external view showing a main configuration of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 3 is a block diagram showing a connection of control of main parts of the ink jet recording apparatus according to the embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of a recording head of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of a head unit of an ink jet recording apparatus according to an embodiment of the invention. FIG. 3 is a diagram illustrating a configuration of a support frame of the ink jet recording apparatus according to the embodiment of the invention. FIG. 3 is a bottom view of the recording head of the ink jet recording apparatus according to the embodiment of the invention. The figure explaining the rotation position adjustment process in the manufacturing method of the head unit of the inkjet recording device in embodiment of this invention. The figure explaining the structure of a rotation position adjustment jig. FIG. 3 is a diagram illustrating a configuration of an eccentric machine screw of the ink jet recording apparatus according to the embodiment of the invention. The figure explaining the structure of a reference | standard scale. The figure explaining the jig alignment process in the manufacturing method of the head unit of the inkjet recording device in the embodiment of the present invention. The figure explaining the grasping | ascertainment of the nozzle position by an optical microscope. FIG. 6 is a diagram showing another example of an eccentric machine screw of the ink jet recording apparatus according to the embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Inkjet recording device, HD ... Recording head, SW ... Support frame, H1-H4 ... Head unit, HS1-HS3 ... Eccentric machine screw, UB ... Unit body

Claims (3)

An inkjet recording apparatus comprising: a recording medium conveying unit that conveys a recording medium; and a recording head that performs recording by ejecting ink droplets from nozzles onto the recording medium conveyed by the recording medium conveying unit,
The recording head is capable of forming dot rows that align a plurality of head units in which a plurality of the nozzles are arranged at predetermined intervals along a main scanning direction orthogonal to the transport direction of the recording medium. Along the intersecting unit arrangement direction, it has a configuration that is detachably arranged side by side on a support frame that supports the plurality of head units,
Each of the plurality of head units has a protrusion provided on the support frame, the protrusion having a protrusion amount adjusted to have a predetermined dimension from a predetermined nozzle outside the unit body of the head unit in plan view. An ink jet recording apparatus, wherein the ink jet recording apparatus is disposed in contact with a reference portion.   The projecting amount is the eccentric member formed by decentering a head having an outer periphery larger than the shaft portion in one end portion of the shaft portion with respect to the shaft portion in the plan view. The head is disposed so as to protrude outward from the unit body and is rotatable about the shaft, and the amount of protrusion of the head from the unit body is a predetermined dimension from the predetermined nozzle. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus is adjusted.   The inkjet recording apparatus according to claim 2, wherein at least three of the eccentric members are arranged on the unit body so that the protruding amount of each of the eccentric members can be adjusted.

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