JP2003211638A - Inkjet printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To adjust a head configuration without separating the head. <P>SOLUTION: Adjusting screws 71a and 73a are arranged respectively at a Y axis positive direction side end part and a Y axis negative direction side end part of a side face perpendicular to an X axis positive direction of a head fixing plate 61. Elastic members 72a and 74a are arranged respectively at a Y axis positive direction side end part and a Y axis negative direction side end part of a side face perpendicular to an X axis negative direction of the head fixing plate 61 to excite the end parts in the X axis positive direction. Moreover, an adjusting screw 75a is arranged at a side face perpendicular to the Y axis negative direction of the head fixing plate 61, and an elastic member 76a is set at a side face perpendicular to the Y axis positive direction of the head fixing plate 61 to excite the side face in the Y axis negative direction. For a head fixing plate 62, adjusting screws 71b, 73b and 75b and elastic members 72b, 74b and 76b are arranged similarly. Moreover, adjusting screws 71c, 73c and 75c and elastic members 72c, 74c and 76c are arranged similarly for a head fixing plate 63. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer for printing an image on a print medium by an ink jet method.

[0002]

2. Description of the Related Art Ink jet printers print by spraying liquid ink onto paper. An inkjet printer includes a plurality of heads for ejecting ink onto a sheet of paper, and a carriage that holds the plurality of heads and that reciprocates in a direction perpendicular to the sheet conveyance direction while facing the sheet of paper. There is something.

In such an ink jet printer, the plurality of heads each have a nozzle row including a large number of ejection nozzles, and in many cases, color inks of different colors are ejected from these ejection nozzles. Therefore, in such an ink jet printer, color inks of different colors are ejected from ejection nozzles that reciprocate together with the head in a direction perpendicular to the paper conveyance direction, and the inks are superimposed on the paper to print an image. To be done.

When the head is not properly attached to the carriage, the nozzle pitch shifts due to this, and the landing positions of the inks ejected from the plurality of ejection nozzles on the paper. May fluctuate. That is, the color inks ejected from the ejection nozzles of the plurality of heads do not overlap on the paper.

In such a case, there is a problem that banding occurs in the image printed on the sheet or the graininess of the image is conspicuous and the image deteriorates. In particular, in order to enable printing of an image having a quality (photo quality) similar to that of a photograph obtained by optical processing, the landing position of ink ejected from the ejection nozzles of a plurality of heads on the paper is It is necessary to print so that they are accurately overlapped without misalignment.

Therefore, in order to solve the above problem, the carriage reciprocating direction (driving axis direction) with respect to the sheet conveying direction and the inclination (angle) of the head with respect to the carriage are often adjusted. That is, when the printer is assembled, the printer is assembled while being adjusted so that the direction and the inclination are appropriate.

[0007]

However, even when the above-mentioned directions and inclinations are properly adjusted and assembled, when the ejection angles of the inks from the ejection nozzles of the plurality of heads are different, the carriage is different. It may be necessary to fine-tune the placement of the head with respect to. At this time, since the arrangement cannot be adjusted with the head attached to the carriage, it is necessary to remove the head from the carriage and then reassemble it while adjusting the arrangement again. Therefore, the arrangement of the head is properly adjusted. Therefore, it takes a considerably long time.

Therefore, an object of the present invention is to provide an ink jet printer which can easily adjust the arrangement of the head without removing the head.

[0009]

In order to achieve the above object, an ink jet printer according to a first aspect of the present invention is an ink discharger having a plurality of heads mounted with a nozzle array including a large number of nozzles, and In a state where a plurality of heads are attached to the ink ejecting section, an adjusting mechanism for individually adjusting the arrangement state of each of the plurality of heads with respect to the ink ejecting section is provided. is there.

According to the first aspect, while confirming the landing position of the ink ejected from the nozzles included in the plurality of heads on the print medium, the arrangement state of each of the plurality of heads with respect to the ink ejecting portion can be adjusted. it can. In addition, since the arrangement state of each of the plurality of heads can be individually adjusted, the adjustment can be performed with high accuracy.
In addition, since a plurality of heads are adjusted while being attached to the ink ejection unit, it is not necessary to consider the mounting error of each head when mounting the heads to the ink ejection unit, and the heads are connected It can be adjusted without removing the ink piping and wiring.
Therefore, the work efficiency in adjusting the arrangement of the heads can be improved.

Here, the "arrangement state of the head with respect to the ink ejection portion" includes both the position and the inclination of the head with respect to the ink ejection portion, or at least one of them.

The ink jet printer according to claim 2 is
The adjusting mechanism has a pressing member arranged to abut one end of the plurality of heads, and an elastic member arranged to abut the other end of the plurality of heads and to face the pressing member. It is characterized by having and.

According to the second aspect, the structure of the adjusting mechanism for adjusting the arrangement of the head with respect to the ink ejecting portion can be simplified.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of an inkjet printer according to an embodiment of the present invention. FIG. 2 is a diagram showing a schematic configuration of the print head unit. FIG. 3 is a diagram showing a schematic configuration of the head. FIG. 4 is a bottom view of the head block showing the schematic configuration of the adjusting mechanism. FIG. 5 is a perspective view of a head block showing a schematic configuration of the adjusting mechanism. In addition,
FIG. 5 is a diagram when the head block is viewed from the lower oblique direction, and the heads 51 to 53 are omitted.

The ink jet printer 1 shown in FIG.
Has a transport table 4, a transport roller unit 5, an inkjet printing unit 6, a pressure roller unit 7, a cutting unit 8, and a discharge roller unit 9 in a substantially rectangular parallelepiped housing 30. Further, in the housing 30, a long sheet 2 having a winding portion 2a wound in a roll shape is formed.
Are arranged. The winding portion 2a of the paper 2 is held by a drum 3 which is rotatable around an axis center. Further, as will be described later, the operation of each part of the inkjet printer 1 is performed by the controller 2 arranged in the housing 30.
Controlled by 0.

The transport roller unit 5 is a controller 2
A pair of drive rollers driven by a motor 25 controlled by 0, for conveying the sheet 2 before being cut by the cutting unit 8. That is, the transport roller unit 5 unwinds the paper 2 from the winding portion 2 a, transports the paper 2 on the transport base 4 to the downstream side, and sequentially passes the inkjet printing unit 6 and the cutting unit 8.

The ink jet printing unit 6 has a print head portion 11 and a suction fan 12. As shown in FIG. 2, the print head unit 11 includes heads 51 to 53.
A head block 44 (see FIGS. 3 and 4),
Carriage 45 for supporting the head block 44
And an annular belt 46 for holding the carriage 45
And rollers 47 and 48 around which an annular belt 46 is stretched.

Here, the heads 51 to 53, as shown in FIG. 3, have a large number of ejection nozzles 51a to 51e capable of ejecting color inks of yellow (yellow), magenta (magenta), and cyan (blue-green). 53a are provided respectively. Here, the large number of ejection nozzles 51a to 53a are connected to the heads 51 to 51.
The nozzle row is arranged along the axial direction of 53. Therefore, the heads 51 to 53, based on the signal from the controller 20, move toward the front surface (the upper surface in FIG. 1) of the conveyed paper 2 and have a large number of ejection nozzles 51a to 5a.
A desired color image can be printed by ejecting each color ink from 3a. The number and arrangement of the discharge nozzles 51a to 53a can be arbitrarily changed. In addition, the ejection nozzles 5 of the heads 51 to 53
It is not always necessary to eject inks of different colors from 1a to 53a. For example, only the black ink may be ejected from all the ejection nozzles 51a to 53a, and a black and white image may be printed. Good.

The head block 44 is a flat plate-shaped member, and the surface (the lower surface in FIG. 2) facing the paper 2 has
As shown in FIG. 4, a plate-shaped head plate 41 for holding the head fixing plates 61 to 63, to which the heads 51 to 53 are fixed, is attached. A recess 41a is formed on the surface of the head plate 41 facing the paper 2 (see FIG. 5). Then, the head fixing plates 61 to 63 (heads 51 to 53) are provided in the recess 41a.
The sheets 2 are arranged so as to be separated from each other along a direction perpendicular to the conveyance direction of the sheet 2. An adjusting mechanism 70 for adjusting the positions of the head fixing plates 61 to 63 is provided in the recess 41 a of the head plate 41. The detailed structure of the adjusting mechanism 70 will be described later.

The head plate 41 is swingably supported by a rotary shaft pin 42 at the center position in the width direction of one end thereof. And the head plate 41
Is adjusted to an appropriate angle with respect to the head block 44, and then the two fixing screws 4 are attached to the head block 44.
It is designed to be fixed by 3.

At the end of the head plate 41 opposite to the end supported by the rotary shaft pin 42, a projection 41b having a sharp tip is formed. When the head plate 41 swings with respect to the head block 44, the protrusion 41 b is formed on the lower surface of the head block 44.
A scale 44a is provided at a position corresponding to. Therefore, when adjusting the inclination of the head plate 41 with respect to the head block 44, the projection 41b and the scale 44a are adjusted.
You can make adjustments while checking the relative position with.

Here, the recess 41a of the head plate 41
The adjusting mechanism 70 provided inside the head fixing plates 61 to 6
Adjustment screws 71a for adjusting the respective positions of
71c and elastic members 72a to 72c, and an adjusting screw 73
a to 73c and elastic members 74a to 74c, and adjusting screws 75a to 75c and elastic members 76a to 76c.

Adjustment screws 71a-71c and elastic member 7
2a to 72c, the adjusting screws 73a to 73c, and the elastic members 74a to 74c are arranged in a direction perpendicular to the conveyance direction of the respective sheets 2 of the head fixing plates 61 to 63, that is, in the reciprocating direction of the heads 51 to 53 (hereinafter, This is for adjusting the position of the head fixing plates 61 to 63 with respect to the head plate 41, as well as adjusting the position in the X-axis direction). Meanwhile, adjusting screws 75a to 75c
The elastic members 76a to 76c are for adjusting the position of the sheet 2 in the transport direction (hereinafter referred to as the Y-axis direction).

When each of the head fixing plates 61 to 63 is shown as the X-axis direction and the Y-axis direction, the center position of each of the head fixing plates 61 to 63 will be described as the origin, and the head plate 41 will be described. Will be described as the X-axis direction and the Y-axis direction, the center position of the head plate 41 will be described as the origin.

The tip of the adjusting screw 71a is in contact with the end of the side surface of the head fixing plate 61 perpendicular to the positive direction of the X axis on the positive side of the Y axis. Here, the adjusting screw 71a is screwed into a screw hole formed in the side wall of the head plate 41 that is perpendicular to the positive direction of the X axis. Therefore, by screwing the adjusting screw 71a into the screw hole, the tip end portion that abuts on the head fixing plate 61 can be advanced, and by screwing the adjusting screw 71a into the screw hole, The tip end portion that abuts the fixed plate 61 can be retracted. The adjusting screw 71a is used for the head fixing plates 62, 63.
It is fitted into the through holes 62a and 63a formed in the.

On the other hand, the tip of the elastic member 72a is in contact with the end of the side surface of the head fixing plate 61 perpendicular to the negative direction of the X axis on the positive side of the Y axis. The elastic member 72a is arranged so as to face the adjusting screw 71a. here,
The elastic member 72a is, for example, a coil spring or the like, and is arranged between the head fixing plate 61 and the inner peripheral surface of the wall surface of the recess 41a of the head plate 41 perpendicular to the negative direction of the X axis.
The end portion of the head fixing plate 61 on the Y axis positive direction side is biased in the X axis positive direction.

Therefore, when the adjusting screw 71a is screwed into the screw hole, the end portion of the head fixing plate 61 on the positive side of the Y-axis moves in the negative direction of the X-axis against the biasing force of the elastic member 72a. When the adjusting screw 71a is moved and screwed into the screw hole, the biasing force of the elastic member 72a causes the adjusting screw 71a to move in the positive direction of the X-axis. That is, the position of the end of the head fixing plate 61 on the positive Y-axis side in the X-axis direction can be adjusted by the adjusting screw 71a and the elastic member 72a.

The tip of the adjusting screw 73a is in contact with the end of the side surface of the head fixing plate 61 which is perpendicular to the positive direction of the X axis on the negative side of the Y axis. Here, like the adjusting screw 71a, the adjusting screw 73a is screwed into a screw hole formed in a side wall of the head plate 41 perpendicular to the positive direction of the X axis. Accordingly, by screwing the adjusting screw 73a into the screw hole, the tip end portion that abuts on the head fixing plate 61 can be advanced, and by screwing the adjusting screw 73a into the screw hole, The tip end portion that abuts the fixed plate 61 can be retracted. Adjustment screw 7
3a is a through hole 6 formed in the head fixing plates 62 and 63.
It is fitted in 2b and 63b.

On the other hand, the tip of the elastic member 74a is in contact with the end of the side surface of the head fixing plate 61 which is perpendicular to the negative direction of the X axis on the Y axis negative direction side. The elastic member 74a is arranged so as to face the adjusting screw 73a. here,
The elastic member 74a is, for example, a coil spring or the like, and is arranged between the head fixing plate 61 and the inner peripheral surface of the wall surface of the recess 41a of the head plate 41 perpendicular to the negative direction of the X axis.
The end of the head fixing plate 61 on the Y axis negative direction side is biased in the X axis positive direction.

Therefore, when the adjusting screw 73a is screwed into the screw hole, the end of the head fixing plate 61 on the negative side of the Y-axis moves in the negative direction of the X-axis against the urging force of the elastic member 74a. When the adjustment screw 73a is moved and screwed into the screw hole, the adjustment screw 73a is moved in the positive direction of the X axis by the urging force of the elastic member 74a. That is, the position of the end of the head fixing plate 61 on the Y axis negative direction side in the X axis direction can be adjusted by the adjusting screw 73a and the elastic member 73a.

Here, the adjusting screw 71a and the elastic member 7
X of the end portion of the head fixing plate 61 on the positive side of the Y axis due to 2a.
Adjusting the tilt of the head fixing plate 61 with respect to the head plate 41 by adjusting the position in the axial direction and adjusting the position of the end of the head fixing plate 61 on the Y axis negative direction side by the adjustment screw 73a and the elastic member 73a in the X axis direction. You can

The tip of the adjusting screw 75a is in contact with the side surface of the head fixing plate 61 which is perpendicular to the negative direction of the Y axis. Here, the adjusting screw 75a is screwed into a screw hole formed in the side wall of the head plate 41 that is perpendicular to the negative direction of the Y axis. Therefore, by screwing the adjusting screw 75a into the screw hole, the tip end portion that abuts on the head fixing plate 61 can be advanced, and by screwing the adjusting screw 75a into the screw hole, Fixed plate 61
It is possible to retract the tip end portion that comes into contact with.

On the other hand, the tip of the elastic member 76a is in contact with the side surface of the head fixing plate 61 which is perpendicular to the positive direction of the Y axis. The elastic member 76a is arranged so as to face the adjusting screw 75a. Here, the elastic member 76a is
For example, a coil spring or the like is arranged between the inner peripheral surface of the wall surface of the recess 41a of the head plate 41 which is perpendicular to the positive direction of the Y axis and the head fixing plate 61, and the head fixing plate 61 has the positive direction of the Y axis. The side end is biased in the Y-axis negative direction.

Therefore, the head fixing plate 61 is provided with the adjusting screw 7
When 5a is screwed into the screw hole, it moves in the Y-axis positive direction against the biasing force of the elastic member 76a, and when the adjusting screw 75a is screwed into the screw hole, the elastic member 76a It is adapted to move in the Y-axis negative direction by the urging force. That is, the position of the entire head fixing plate 61 in the Y-axis direction can be adjusted by the adjusting screw 75a and the elastic member 76a.

As for the head fixing plate 62, the position of the end of the head fixing plate 62 on the positive Y-axis side in the X-axis direction is adjusted by the adjusting screw 71b and the elastic member 72b, similarly to the head fixing plate 61. Can be adjusted screw 7
3b and the elastic member 74b, the head fixing plate 62
It is possible to adjust the position in the X-axis direction of the end portion on the Y-axis negative direction side, and to adjust the inclination of the head fixing plate 62 relative to the head plate 41. Further, the position of the entire head fixing plate 62 in the Y-axis direction can be adjusted by the adjusting screw 75b and the elastic member 76b.

With respect to the head fixing plate 63, the position of the end of the head fixing plate 63 on the Y axis positive direction side in the X axis direction can be adjusted by the adjusting screw 71c and the elastic member 72c. With the elastic member 74c, the position of the end of the head fixing plate 63 on the Y axis negative direction side in the X axis direction can be adjusted, and the inclination of the head fixing plate 63 with respect to the head plate 41 can be adjusted. Further, the position of the entire head fixing plate 63 in the Y-axis direction can be adjusted by the adjusting screw 75c and the elastic member 76c.

Here, the head fixing plates 61 to 63 are arranged so as to be sufficiently separated from each other so as not to come into contact with each other when the positions or the inclinations in the X-axis direction and the Y-axis direction with respect to the head plate 41 are adjusted. ing. Therefore, proper adjustment can be performed for each of the head fixing plates 61 to 63.

As described above, the heads 51 to 53 are provided on the lower surfaces (upper surfaces in FIG. 5) of the head fixing plates 61 to 63.
Are fixed respectively, the head fixing plates 61 to 6
3, the heads 51 to 53 move. That is, the positions and the inclinations of the head fixing plates 61 to 63 are adjusted so that the heads 51 to 53 are arranged at the proper positions and the inclinations with respect to the head plate 41.

The carriage 45, which supports the head block 44 provided with the adjusting mechanism 70, is held by an annular belt 46, as shown in FIG. Further, the annular belt 46 is spanned by rollers 47 and 48 which are rotatable around rotary shafts (not shown) fitted and inserted in the respective axial center positions. The rollers 47 and 48 are arranged at intervals larger than the width of the sheet 2. The annular belt 46 is arranged so as to be substantially perpendicular to the conveyance direction of the paper 2.

Here, the roller 47 is a driving roller that is rotationally driven by a motor (not shown), and the roller 48 is a driven roller that is rotated by the rotation of the roller 47 being transmitted through the annular belt 46. It's Laura. Therefore, when the roller 47 is rotated, the annular belt 46 also rotates in the same direction. Then, when the roller 47 is rotated in one direction by a predetermined angle, the rotation direction is changed, and this time, the roller 47 is rotated in the opposite direction by a predetermined angle, and the rotation direction is changed again. After that, this operation is repeated, and as the roller 47 rotates, the annular belt 46 moves back and forth, so that the carriage 45
Can reciprocate between the vicinity of one end and the vicinity of the other end of the paper 2 in the width direction. Here, the predetermined angle of the roller 47 corresponds to the distance that the carriage 45 reciprocates between the vicinity of one end and the vicinity of the other end of the paper 2 in the width direction.

The print head unit 11 of the ink jet printing unit 6 prints on the paper 2 by ejecting liquid ink from the nozzles dot by dot, and is of a piezo jet type, a thermal jet type or other types. Any one may be adopted.

Further, the suction fan 12 is arranged at a position facing the print head portion 11 with the conveyance path of the sheet 2 interposed therebetween, and the conveyance table 4 is provided through an opening (not shown) formed in the conveyance table 4. It is for adsorbing the upper sheet 2.
Therefore, the paper 2 facing the print head unit 11 is the paper 2
Fan 12 arranged on the back side (bottom surface in FIG. 1) of the
Is sucked into the carrier table 4 and is transported in close contact therewith,
The distance from the print head unit 11 is constant. This is because when the paper 2 is curled, a part of the paper 2 is largely separated from the transport table 4 to suppress the occurrence of a printing defect due to a change in the distance from the print head unit 11. .

The pressure roller unit 7 holds the sheet 2 conveyed between the ink jet printing unit 6 and the cutting unit 8. Here, by disposing the pressure bonding roller unit 7 between the inkjet printing unit 6 and the cutting unit 8, it is possible to properly perform the image printing by the inkjet printing unit 5 and the cutting of the paper 2 by the cutting unit 8. Becomes

The cutting unit 8 includes a moving blade 8a arranged on the same side as the print head 11 with respect to the paper 2, and the paper 2
It has a fixed blade 8b arranged so as to face the movable blade 8a with the blade sandwiched therebetween. The movable blade 8a and the fixed blade 8b are
Both are rectangular blades having a width slightly larger than the width of the paper 2. The movable blade 8a can be moved toward or away from the fixed blade 8b by the motor 27 controlled by the controller 20, and can move the printed sheet 2 conveyed from the upstream side of the conveyance path. , Can be cut along the width direction by the interaction with the fixed blade 8b. By cutting in this way, the printed paper 2 is divided into a predetermined length.

The discharge roller unit 9 is the controller 2
It is a drive roller pair driven by a motor 26 controlled by 0, and conveys the printed paper 2 cut by the cutting unit 8 and discharges it from the discharge port 30a.

The controller 20 performs a predetermined process on the image signal supplied from an input interface (not shown), and supplies a print signal containing image data corresponding to the image to be printed to the ink jet printing unit 6. Further, the controller 20 can supply a drive signal to the transport roller unit 5 and the discharge roller unit 9 at appropriate transport timing, and can control the print timing in the inkjet printing unit 6 and the cut timing in the cutting unit 8.

Next, the procedure for adjusting the arrangement of the heads 51 to 53 with respect to the head plate 41 in the ink jet printer 1 according to this embodiment will be described. FIG. 6 is a diagram showing a confirmation pattern before the arrangement state of the heads is adjusted. FIG. 7 is a diagram showing a confirmation pattern after the arrangement of the heads has been adjusted. 6 and 7, the dots printed on the paper 2 by the ink ejected from the ejection nozzles 51 a of the head 51 are indicated by “◯”, and the ink ejected from the ejection nozzles 52 a of the head 52 is indicated. The dots printed on the paper 2 by the mark “Δ” are indicated by the ink discharged from the discharge nozzles 53 a of the head 53.
The dots printed above are indicated by "□".

When the ink jet printer 1 is assembled, the head plate 41 holding the heads 51 to 53 is arranged so that the heads 51 to 53 are arranged substantially parallel to the transport direction of the paper 2. It is fixed to. In addition, when the heads 51 to 53 are not parallel to the conveyance direction of the sheet 2 and are largely displaced,
The inclination of the head plate 41 with respect to the head block 44 is adjusted while confirming the relative position between the protrusion 41b and the scale 44a.

First, while the paper 2 is fixed to the ink jet printing unit 6, the heads 51 to 53 are moved together with the carriage 45 in a direction perpendicular to the transport direction of the paper 2, and the ejection of each of the heads 51 to 53 is performed. Ink is ejected from the nozzles 51a to 53a, and a confirmation pattern is printed in a predetermined area on the paper 2.

In the present embodiment, as shown in FIG. 6, while the heads 51 to 53 are scanned once in the width direction of the paper 2, the discharge nozzles 51a to 53a respectively perform 6 times at predetermined time intervals. Only the ink is ejected and the confirmation pattern is printed. Therefore, as the confirmation pattern, a total of 36 dots arranged in the width direction of the sheet 2 are separated from each other by the distance x and in the transport direction of the sheet 2 are separated from each other by the distance y. ~
Printing is performed by the respective ejection nozzles 51a to 53a of 53.

The ejection nozzles 51 of the heads 51 to 53 are
a to 53a corresponding to the discharge nozzles 51a to
The ink ejected from 53a is ejected from each of the ejection nozzles 51a to 53a at a timing such that the ink is printed so as to overlap the same landing position on the paper 2. That is, for example, the ink ejected from the ejection nozzles 51 a to 53 a arranged near the respective end portions of the heads 51 to 53 prints dots so that they are overlapped at the same position on the paper 2.

Here, FIG. 6 shows a confirmation pattern printed before the arrangement state of the heads 51 to 53 is adjusted. The confirmation pattern is printed on the paper 2 by the ink ejected from the ejection nozzles 51a to 53a. Dots are printed in different areas without overlapping each other.

The confirmation pattern printed before the arrangement of the heads 51 to 53 is adjusted will be described in detail.
The sheet 2 is formed by the ink ejected from the ejection nozzle 51a.
Dots printed on top (hereinafter referred to as dot group 81)
Based on the above, the dots printed on the paper 2 by the ink ejected from the ejection nozzle 52a (hereinafter,
In the dot group 82), the end of the dot group 82 on the Y-axis positive direction side is displaced in the X-axis positive direction by a distance a1, and the end of the dot group 82 on the Y-axis negative direction side is the X-axis positive direction. To distance a2
And the entire dot group 82 is displaced in the negative direction of the Y-axis by the distance a3.

The dots printed on the paper 2 by the ink ejected from the ejection nozzles 53a (hereinafter referred to as the dot group 83) are based on the dot group 81. The end on the direction side is displaced in the positive direction of the X axis by a distance b1, the end on the negative side of the Y axis of the dot group 83 is displaced in the positive direction of the X axis by a distance b2, and the entire dot group 83 is in the Y axis. It is displaced in the positive direction by a distance b3.

Therefore, in order to make all the dot groups 81 to 83 overlap, the head plate 41 is offset by the amount of the dot groups 82 and 83 displaced from the dot group 81.
The positions of the heads 51 to 53 may be adjusted in the direction opposite to the above-described direction.

Here, in the adjustment of the arrangement of the head 52 with respect to the head plate 41, the head fixing plate 62 having the head 52 fixed thereto is screwed with the adjusting screw 71b into the screw hole to fix the head. By moving the end of the plate 62 on the Y axis positive direction side by a distance a1 in the X axis negative direction and screwing the adjusting screw 73b into the screw hole, the end of the head fixing plate 62 on the Y axis negative direction side. The unit is moved in the negative direction of the X axis by a distance a2. Further, by screwing the adjusting screw 75b into the screw hole, the entire head fixing plate 62 is moved in the Y-axis positive direction by the distance a3.

Similarly, in adjusting the arrangement of the head 53 with respect to the head plate 41, the head fixing plate 63 having the head 53 fixed thereto is screwed with the adjusting screw 71c into the screw hole. Y of head fixing plate 63
The end on the Y axis negative direction side of the head fixing plate 63 is moved by moving the end on the Y axis negative direction by a distance b1 in the X axis negative direction and screwing the adjusting screw 73c into the screw hole. The distance b2 is moved in the negative direction. In addition, the adjusting screw 75
By screwing c into the screw hole, the entire head fixing plate 63 is moved in the Y-axis negative direction by the distance b3.

After adjusting the arrangement of the heads 51 to 53 with respect to the head plate 41 in this way, the confirmation pattern is printed again in the same manner as described above.

Then, the dot group 82 of the confirmation pattern is
From the state shown in FIG. 6, the end on the positive side of the Y axis is X.
It is printed so that it moves a distance a1 in the negative direction of the axis, its end on the negative Y-axis side moves a distance a2 in the negative X-axis direction, and further moves a distance a3 in the positive Y-axis direction. Therefore,
The dot group 81 and the dot group 82 are printed so as to overlap each other.

Similarly, the dot group 83 of the confirmation pattern is
From the state shown in FIG. 6, the end on the positive side of the Y axis is X.
Printing is performed so that the end portion on the Y-axis negative direction side is moved by a distance b2 in the Y-axis negative direction, and the end portion on the Y-axis negative direction side is moved by a distance b3 in the Y-axis negative direction. Therefore,
The dot group 81 and the dot group 83 are printed so as to overlap each other.

That is, as shown in FIG.
The dots ejected from the ejection nozzles 51a to 53a of 53 are printed so that the dot groups 81 to 83 are overlapped with each other.

As described above, in the ink jet printer 1 according to the present embodiment, while confirming the landing position of the ink ejected from the ejection nozzles 51a to 53a included in the heads 51 to 53 on the paper 2, the head is confirmed. The position and inclination of each of the heads 51 to 53 with respect to the plate 41 can be adjusted. Also, the head 51 to
Since each position and inclination of 53 can be adjusted individually, the adjustment can be performed accurately. Also,
Since the heads 51 to 53 are adjusted in a state of being attached to the head plate 41, it is not necessary to consider an attachment error of each head when attaching the heads 51 to 53 to the head plate 41, and the head 51 ~
The adjustment can be performed without removing the ink pipe and wiring connected to 53. Therefore, the heads 51 to
The work efficiency in the arrangement adjustment of 53 can be improved.

The adjusting mechanism 70 includes the head fixing plate 61.
Adjusting screws 71a to 71c and elastic members 72a to 7 arranged so as to come into contact with respective facing surfaces of
2c, adjusting screws 73a to 73c and elastic members 74a to
74c or the adjusting screws 75a to 75c and the elastic members 76a to 76c, the structure for adjusting the arrangement of the heads 51 to 53 with respect to the head plate 41 can be simplified.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various design changes are possible within the scope of the claims. Is. For example, in the above-described embodiment, the print head unit 11 in which the three heads 51 to 53 are arranged so as to be separated from each other along the direction perpendicular to the transport direction of the sheet 2 has been described. The number and arrangement of the heads can be arbitrarily changed as long as the print head unit is attached. Therefore, a plurality of heads may be arranged so as to be separated from each other along the sheet conveying direction, and for example, the head plate 41.
In addition, as shown in FIG. 8, the heads 151 to 157 and the head fixing plates 161 to 167 are separated from each other in the direction perpendicular to the conveyance direction of the sheet 2 and are separated from each other along the conveyance direction of the sheet 2. It may be arranged. Although an adjustment mechanism for adjusting the arrangement of the head fixing plates 161 to 167 is omitted in FIG. 8, the arrangement of each of the head fixing plates 161 to 167 is adjusted as in the present embodiment. An adjusting mechanism is provided for this purpose.

In the above embodiment, the dot group 8
Although the case where the deviations of the dot groups 82 and 83 are confirmed with reference to 1 and then the dot groups 82 and 83 are adjusted so as to overlap the dot group 81 is described, the present invention is not limited to this, and the dot groups 81 to 81- It suffices that the 83 be adjusted so that all of them overlap. Therefore, also in the present embodiment, the dot groups 81 and 83 may be adjusted so as to overlap the dot group 82, or the dot groups 81 and 82 may be adjusted so as to overlap the dot group 83.

However, like the dot group 81 of the present embodiment, the dot group in which each dot is arranged in parallel both in the conveying direction of the paper 2 and in the direction perpendicular to it is overlapped with the other dot group. Is preferably adjusted as follows. Therefore, in the present embodiment, the dots of the dot group 81 are arranged in parallel both in the transport direction of the paper 2 and in the direction perpendicular thereto, so that the dot group 81 is not adjusted in its arrangement. However, when the dots of the dot group 81 are not arranged in parallel to at least one of the transport direction of the paper 2 and the direction perpendicular to the transport direction of the paper 2, the dot group 81 should also be arranged in the transport direction of the paper 2. It is preferable to adjust so that the dot groups 82 and 83 overlap with the dot group 81 after the adjustment so that the dots are arranged in parallel in any direction perpendicular thereto.

Further, in the above embodiment, the adjusting mechanism 7
The adjusting screws 71a to 71c and the elastic members 72a to 72c, and the adjusting screws 73a to 73c, which are arranged so that 0 abuts on the respective facing surfaces of the head fixing plates 61 to 63.
And elastic members 74a to 74c or adjusting screw 75a
~ 75c and the elastic members 76a to 76c have been described, the present invention is not limited to this.
Any configuration may be used as long as the arrangement of the head fixing plates 61 to 63 can be adjusted.

Further, in the above embodiment, the adjusting mechanism 7
0 is the head fixing plate 61 to the head plate 41
Although the case where the respective positions and the inclinations of 63 are adjustable has been described, one of the respective positions and the inclinations of the head fixing plates 61 to 63 with respect to the head plate 41 may be adjustable. .

Further, in the above-described embodiment, the inclination of the head fixing plates 61 to 63 with respect to the head plate 41 is such that the end on the Y-axis positive direction side and the end on the Y-axis negative direction side are in the X-axis direction. Although the case where the adjustment is performed by moving the heads is described, the present invention is not limited to this, and any configuration for adjusting the inclination of the head fixing plates 61 to 63 with respect to the head plate 41 may be used. Good.
Therefore, for example, the head plate is divided with respect to each of the heads 51 to 53 and is swingably supported, and the head plate on which the heads 51 to 53 are arranged is swung with respect to the head block. The inclination of the heads 51 to 53 may be adjusted.

In addition to paper, thin plastic or the like can be used as the print medium in the ink jet printer of the present invention.

[0071]

As described above, according to the first aspect, while confirming the landing position of the ink ejected from the nozzles included in the plurality of heads on the print medium, each of the plurality of heads with respect to the ink ejecting portion is confirmed. The arrangement state of can be adjusted. In addition, since the arrangement state of each of the plurality of heads can be individually adjusted, the adjustment can be performed with high accuracy. In addition, since a plurality of heads are adjusted while being attached to the ink ejection unit, it is not necessary to consider the mounting error of each head when mounting the heads to the ink ejection unit, and the heads are connected to the heads. It can be adjusted without removing the ink piping and wiring. Therefore, the work efficiency in adjusting the arrangement of the heads can be improved.

According to the second aspect, the structure of the adjusting mechanism for adjusting the arrangement of the head with respect to the ink ejecting section can be simplified.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of an inkjet printer according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a schematic configuration of a print head unit.

FIG. 3 is a diagram showing a schematic configuration of a head.

FIG. 4 is a bottom view of a head block showing a schematic configuration of an adjustment mechanism.

FIG. 5 is a perspective view of a head block showing a schematic configuration of an adjusting mechanism.

FIG. 6 is a diagram showing a confirmation pattern before the arrangement state of heads is adjusted.

FIG. 7 is a diagram showing a confirmation pattern after the arrangement state of heads is adjusted.

FIG. 8 is a diagram showing a schematic configuration of another head.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Paper 6 Inkjet printing unit 11 Print head part (ink discharge part) 41 Head plate 44 Head block 45 Carriage 51-53 Heads 51a-53a Discharge nozzle (nozzle) 61-63 Head fixing plates 71a-71c, 73a- 73c, 75a-75c Adjustment screw (pressing member) 72a-72c, 74a-74c, 76a-76c Elastic member 81-83 Dot group

Claims (2)

[Claims] 1. An ink ejection unit having a plurality of heads, in which a nozzle row including a large number of nozzles is arranged, and an ink ejection unit for the ink ejection unit in a state where the plurality of heads are attached to the ink ejection unit. An inkjet printer, comprising: an adjusting mechanism for individually adjusting the arrangement state of each of the plurality of heads. 2. The adjusting mechanism includes a pressing member arranged to abut one end of the plurality of heads, and an abutting member to the other end of the plurality of heads and to face the pressing member. The inkjet printer according to claim 1, further comprising an elastic member arranged.