JP2002059568A - Ink jet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet printer which records at high speeds by concurrently executing a maintenance process such as wiping and recording. SOLUTION: A head module 41 of the ink jet printer has a rotary shaft 43 fixed to both end faces of short sides of a substrate 23 and is supported to be alternately rotatable half as indicated by an arrow F to a frame of a printer body. While one printing head 40a prints at a recording position to a paper 42 transferred in a vertical scanning direction of an arrow E, the other printing head 40b is primed and wiped by a maintenance unit 44 at a maintenance position, and then capped to rest. The head module 41 is rotated half by every predetermined period to positionally interchange the printing heads 40a and 40b, so that recording and maintenance are alternately concurrently executed.

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 in which maintenance such as wiping and priming and printing are performed in parallel to increase the printing speed.

[0002]

2. Description of the Related Art Conventionally, an ink jet printer has been used. The printing method in this ink jet printer is to print (print) characters, images, and the like by discharging ink droplets from discharge nozzles of a print head and absorbing the ink droplets to a recording material such as paper or cloth. It is. This printing method is a printing method that generates less noise, is quiet, has no special fixing process, can perform relatively high-speed printing, and can perform full-color printing.

[0003] Full-color printing is usually performed on three color inks of the subtractive primary colors yellow (yellow), magenta (red dye name) and cyan (greenish blue), and on black portions of characters and images. Printing is performed using four colors of ink to which black (black) is used. That is, a nozzle row dedicated to each color is arranged in one print head, and four color inks of yellow, magenta, cyan, and black are discharged from these nozzle rows while controlling the discharge amount of each color, For example, full-color printing is performed by mixing and absorbing each ink in one pixel area of the recording material.

In a print head of an ink jet printer that discharges ink droplets from the above-mentioned discharge nozzles, a heating element is arranged in a fine ink pressurizing chamber, and an electric pulse is applied to the heating element to heat the heating element. Using a thermal inkjet head that ejects ink droplets using force and an electromechanical transducer such as a piezo element, a pressure is also generated by mechanical deformation in a fine ink pressurization chamber, and the pressure ejects the ink. There is a piezo type inkjet head that ejects ink droplets from nozzles.

[0005] Further, the above-mentioned thermal type ink jet head has two configurations depending on the ejection direction of ink droplets. One is a side shooter type that discharges ink droplets in a direction parallel to the heating surface of the heating element, and the other is a roof shooter type that discharges ink droplets in a direction perpendicular to the heating surface of the heating element. It is called. In particular, it is known that a roof shooter type print head requires extremely low power consumption as compared with a side shooter type print head.

As a method of manufacturing this roof shooter type print head (thermal type ink jet head), for example, a silicon wafer having a diameter of 6 × 25.4 mm or more has a size of about 10 mm × 15 mm and 90 or more pieces. Silicon LSI on a large number of chip substrates
There is a method of monolithically forming a large number of heating elements and electrode wirings, driving circuits, ink flow paths, ejection nozzles, and the like that individually drive these heating elements by using a forming technique and a thin film forming technique.

FIG. 8A is a perspective view showing the ink ejection surface of such a thermal roof shooter type print head, and FIG. 8B is a sectional view taken along the line AA 'of FIG. FIG. 1A shows the printing paper P in a transparent manner. The configuration of the print head and the general manufacturing method will be described with reference to FIGS. In the print head 1, a drive circuit 3 composed of a diffusion layer is formed on an upper surface of a chip substrate 2 by an LSI formation processing technique. Then, an individual wiring electrode 4 connected to the drive circuit 3, a heating section 5 having one end connected to the individual wiring electrode 4, and a common electrode 6 connected to the other end of the heating section 5.
Are formed by a thin film forming technique such as sputtering, a mask pattern forming technique such as photolithography, and a patterning technique such as etching.

The heating portions 5 are formed with a large number of heating portions, for example, 64, 128, 256, etc., at a fine arrangement pitch of, for example, 20 to 40 μm, depending on the design policy. The common electrode 6 has a central opening that extends in the longitudinal direction of the chip substrate 2.
At this time, a connection electrode terminal 7 for connecting the drive circuit 3 or the common electrode 6 to the outside is formed at one end in the longitudinal direction of the chip substrate 2 together with the wiring electrode.

Then, in the central opening of the common electrode 6,
An ink supply groove 8 is formed along the shape of the opening by, for example, sandblasting technology, and an ink supply hole 9 penetrating from the bottom surface of the ink supply groove 8 to the back surface of the chip substrate 2 is similarly formed by sandblasting. Is formed.

The connection electrode terminals 7 on the chip substrate 2
A height of about 10 μm is formed between the portion surrounding the entire periphery except for the portion where the
m partition walls 11 (11-1, 11-2, 11-3) are stacked by thin film formation by sputtering, mask formation by photolithography, patterning by etching, and solidification by baking.

The partition 11-1 surrounding the entire periphery of the chip substrate 2 blocks the internal structure on the chip substrate 2 from the outside, and the partition 13-2 continuously covers the individual wiring electrodes 4. The partition 13-3 extending from the partition 13-2 between the heat generating portions 5 and the heat generating portions 5 forms the ink pressurizing chambers 12 that individually surround the heat generating portion 5 from three sides. .

Then, a top plate 13 is placed on these partition walls 11.
Are attached by heating and crimping. By stacking the top plate 13, an ink flow path 14 having a height of about 10 μm from the ink supply groove 8 to the ink pressurizing chamber 12 is formed. Discharge nozzles 15 are formed in the top plate 13 at positions facing the heat generating portions 5 by a metal mask pattern forming technique and a helicon wave etching technique, for example. Thus, the number of the ejection nozzles 15 equal to the number of the heating portions 5 is
However, one nozzle row 16 is formed on the top plate 13.

With such a shape, the print heads 1 are completed on a number of chip substrates 2 partitioned on a silicon wafer (not shown). And finally, the silicon wafer is cut along the scribe line using a dicing saw or the like and cut off individually for each chip substrate 2.
Die-bonding to the mounting board and terminal connection by wire bonding or the like complete the printhead module in practical units.

In the print head 1, ink supplied from an external ink cartridge or the like to the ink supply hole 9 is supplied to the ink pressurizing chamber 12 via the ink supply groove 8 and the ink flow path 14, and the print head 1 is used for printing. The heat generating portion 5 is selectively energized according to print information and generates heat instantaneously, causing a film boiling phenomenon at an interface between the heat generating portion 5 and the ink, and corresponding to the heat generating portion 5 by the growth pressure of the film bubble. Ink droplets are ejected from the ejection nozzles 15. The ink droplet becomes a print dot having a size approximately twice as large as that of the ink droplet, and lands on the printing surface of the paper P conveyed in the sub-scanning direction indicated by the arrow B in FIG.
As a result, an image is formed on the sheet surface.

Generally, printers are roughly classified into two types: serial printers and line printers. The serial printer performs printing by scanning a print head in the width direction (main scanning direction) of a print area. On the other hand, a line type printer uses a full array type print head which has a longer length by arranging ejection nozzles to fill the print area in the main scanning direction, and fixing the print head to the printer main body side, and only printing paper. This is a transport method. This line type printer is economical because the mechanical operation is only for transporting the paper, so that the load on the drive system is small and the power consumption is small.

Further, since the line type printer itself is a printer corresponding to high speed, in order to respond to a strong demand for higher printing speed especially in business, as in recent years, a serial type printer is required. Line-type printers are more promising than
This will be central to future development.

FIGS. 9A and 9B are diagrams schematically showing two examples of the configuration of a print head of such a line type printer.
There are roughly two methods for realizing the print head of the line type printer. FIG. 9A shows the first method. The print head 17 shown in FIG. 5A is obtained by mounting a single head chip 18 having a longer length on a parent substrate 19. The parent board 19 is fixed to the printer main body, and a sheet (not shown) is conveyed in the sub-scanning direction indicated by an arrow C in the figure to perform printing.

FIG. 9 (b) shows a second method. The print head 20 shown in FIG. 9 (b) includes a plurality of print heads shown in FIGS.
(b) A small head chip 21 as shown in (b) is mounted and arranged in a staggered manner in the longitudinal direction of a parent substrate 22.
The reason why the head chips 21 are staggered and staggered in this manner is that there is an edge without a discharge nozzle at the end of the head chip 21. However, since the outermost discharge nozzles of the adjacent head chips exist at a distance twice as long as the edge, the discharge nozzles of each head chip 21 are not continuous at the correct interval. This is because the staggered arrangement allows all the ejection nozzles in the main scanning direction to be continuous at correct intervals. This print head 2
Also in the case of 0, the master board 22 is fixed to the printer main body, and a sheet (not shown) is conveyed in the sub-scanning direction indicated by the arrow D in the drawing to perform printing.

The print head 17 according to the first method described above
Are often formed on a semiconductor substrate such as a silicon wafer.
Can be formed only in a limited portion such as the center of a substantially circular silicon wafer. Therefore, there is a drawback that the number of pieces is reduced, the yield is reduced, and the cost is increased, but there is an advantage that the print head 17 as a whole becomes smaller.

The print head 20 according to the second method is
Although the manufacturing yield of the head chips 21 is good, there is an advantage that the cost is low, but the head chips 21 are arranged in a staggered manner, so that the entire print head 20 becomes large,
The ink supply path from the externally mounted ink tank to the head chip 21 is complicated, which has the disadvantage of lowering reliability and increasing costs. The print head (17 or 20) prepared by any of the methods has advantages and disadvantages.

In the above-described ink jet type print head, since the ink always stays in the discharge nozzle in a printing standby state, a drying prevention mechanism such as capping is provided in the print head. Also, the drying proceeds and the viscosity increases due to the evaporation of the water content of the ink.
Therefore, the discharge nozzle may be clogged as it is. In addition, even during printing, individual nozzles may have a pause period, so if printing is performed as it is, the ink in the nozzles not used for printing will also dry out and thicken. In addition, there is a possibility that some of the multiple discharge nozzles may cause clogging and cause discharge failure.

Accordingly, not only when the power is turned on after the printer body is suspended but also during printing, in order to recover the discharge function failure due to clogging which may have occurred, The recovery mechanism periodically performs wiping, which is a wiping process of the ink ejection surface by the wiping member, and priming, which is an idle ejection process of ink (ink ejection without printing) by all ejection nozzles. I have.

[0023]

However, FIG.
(a) The print head 17 or 20 having the configuration shown in (b)
Also in the above, the process of recovering the ejection function by the above-described recovery mechanism, in particular, the process of wiping the ink ejection surface by the wiping member in the wiping is performed in the longitudinal direction of the print head, so that it takes time. Even if a print head such as a line type head capable of high-speed printing is used, there is a problem that the actual printing speed is not as high as expected.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances,
It is an object of the present invention to provide an ink jet printer in which a recording speed is improved by performing maintenance such as wiping and priming and recording in parallel.

[0025]

The construction of the ink jet printer according to the present invention will be described below. The inkjet printer of the present invention is an inkjet printer that performs recording by applying pressure to ink and ejecting the ink in a predetermined direction from a discharge nozzle to land on paper.
A plurality of inkjet heads, a maintenance means detachably mounted on an ink ejection surface of the inkjet head to perform maintenance processing for maintaining proper ejection performance of the ejection nozzles, and a plurality of inkjet heads respectively. Drive control means for performing recording and maintenance processing by the maintenance means in parallel,
Is configured.

A plurality of the ink jet heads are respectively mounted on at least two surfaces of one rotatably supported base, and each of the plurality of ink jet heads is mounted on the at least two surfaces. The inkjet head of (1) is configured to move to a recording position where recording is performed and a maintenance position where maintenance processing is performed by rotation of the base.

Further, two ink jet heads may be provided, for example, such that the ink jet heads are provided on opposing end surfaces of the base having a rectangular parallelepiped shape. Further, for example, as described in claim 4, two ink jet heads are provided, and the two ink jet heads are respectively installed on opposing end faces forming a rectangular parallelepiped of a fixed base, and the two ink jet heads are provided. A paper transport path is provided for each recording position of the head, the maintenance means is provided for each of the ink jet heads, and these maintenance means are movably disposed at a printing retract position and a maintenance position, respectively. May be.

It is preferable that the ink jet head is a full array head having a discharge nozzle array corresponding to substantially the entire width of the recording area of a sheet. Then, the maintenance process includes, for example, capping, wiping,
This is a process for performing at least one of priming.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a head module of a line type ink jet printer (hereinafter, simply referred to as a printer) according to a first embodiment, and FIGS. 2 (a) and (b) and FIGS. 3 (a) and 3 (b). FIG. 4 is a diagram showing a manufacturing process order of the head module. 2 (a) and 2 (b), FIGS. 3 (a) and 3 (b), and FIG.

As shown in FIGS. 2 (a) and 2 (b), in this head module, the substrate 23 is a flat substrate made of ceramic, and a pair of large main planes 24 (24-
1 and 24-2, where 24-2 is the lower side in FIGS. 2 (a) and 2 (b) and cannot be seen). The pair of end faces 25 (25
-1, 25-2 where 25-2 is obliquely leftward and invisible in FIGS. 2 (a) and 2 (b)). FIG. 2 shows a pair of end surfaces 26 (26-1, 26-2;
(a) and (b) are diagonally far right and invisible, and have a hexahedral (cuboid) shape.

The four end faces 25-1, 25-2, 26
-1, 26-2, a pair of end surfaces 26-1, 2 on the short side
An ink introduction path 27 penetrating from one end face to the other end face is formed between 6-2, and between the pair of end faces 25-1 and 25-2 on the long side and the ink introduction path 27. Is
4 penetrating from each end face to the ink introduction path 27;
Each of the ink supply holes 28 is formed. These ink introduction paths 27 and ink supply holes 28 are
3 is formed simultaneously with the formation.

Each of the long sides of the pair of main planes 24 is formed to be long in a direction orthogonal to the long side, and the long side end face 25 is formed.
A plurality of individual wiring electrodes 29, which are bent at right angles and formed short, are arranged at a predetermined pitch. The short-side individual wiring electrode 29 is formed on the long side end face 25.
Further, a common electrode 31 is formed on one surface except for the ink supply hole 28.

The individual wiring electrodes 29 and the common electrode 31 are formed by laminating an electrode material on the substrate 23 and patterning and etching by photolithography. Alternatively, when the resistance of the common electrode 31 may be slightly increased, the common electrode 31 may be formed by a photolithography technique using a photosensitive conductive paste. If sufficient processing accuracy can be obtained, it may be formed using a screen printing technique.

Subsequently, as shown in FIG. 3B, a number of heat generating portions 32 corresponding to the number of the individual wiring electrodes 29 are formed between the individual wiring electrodes 29 and the common electrode 31. Heating part 32
Is formed by patterning a heating resistor film, and at least partially overlaps the individual wiring electrode 29 and the common electrode 31. Even if the heat generating portion 32 is formed in this manner, there is no problem because only the portion where the individual wiring electrode 29 or the common electrode 31 does not actually generate heat does not cause any problem. It is already determined when the common electrode 31 is formed.

As shown in FIGS. 3A and 3B, the heat generating portions 32 are arranged in two rows in the longitudinal direction so as to sandwich the common electrode 31, and the heat generating portions 32 are arranged between the rows. , The heaters 32 in the row are displaced by half the arrangement pitch. 2 (a) and 2 (b) and FIGS. 3 (a) and 3 (b), for convenience of illustration, the length of the substrate 23 in the long side direction is shorter than the actual length. In addition, the number of the individual wiring electrodes 29, that is, the number of the heat generating portions 32 is smaller than the actual number.
Further, it is desirable that the substrate 23 be formed such that the smoothness of both end surfaces on the long side where the heat generating portion 32 is formed is the highest.

FIG. 3A shows a long side end surface 25 (25-1, 25-1).
FIG. 3A is a front view of FIG.
Partition walls 33 (33-1, 33-2) having a height of about 10 μm.
Is formed. The partition wall 33 surrounds the periphery of the region where the heat generating portion 32 and the ink supply hole 28 are formed on the long side end face 25, and the seal partition wall 33-1 laminated on the individual wiring electrode 29 and the common electrode 31 is formed. An ink pressurizing chamber 34 extending from the seal partition 33-1 to each heat generating portion 32 and a partition partition 33-2 formed extending between the heat generating portions 32, and surrounding the individual heat generating portions 32 from three sides.
And an ink passage 35 for guiding the ink from the ink supply hole 28 to the ink pressurizing chamber 34. This partition 3
Reference numeral 3 is formed by sputtering, photolithography, etching, and baking using a photosensitive polyimide or the like.

By the way, a substrate 23 made of a rigid material such as ceramic and a partition 33 made of a resin material such as polyimide are suitable.
Have generally different coefficients of thermal expansion. Therefore, when the head module is lengthened in this way, the head module may be broken due to internal stress generated by a temperature change.

Therefore, as shown in FIG. 3B, slits are formed in portions of the elongated seal partition 33-1 and the partition partition 33-2 extending from the seal partition 33-1 which do not come into contact with ink. It is desirable to form 36 in advance. Here, FIGS. 3A and 3B are shown as separate steps, but in actuality, when the slits 36 are formed, the slits 36 are formed simultaneously with the formation of the partition walls 33.

Subsequently to the above, as shown in FIG.
The top plate 37 is stuck on 3. Then, two rows of discharge nozzles 38 are provided on the top plate 37 at a position facing the heat generating portion 32.
To form As described above, the arrangement of the two rows of the heating sections 32 corresponding to the discharge nozzles 38 is different from the arrangement of the heating sections 32 in the row.
Are displaced from each other in the column direction by の of the arrangement pitch of the nozzles. They are formed so as to be shifted from each other by two in the column direction.

The attachment of the top plate 37 and the formation of the discharge nozzles 38 are almost the same as those in FIGS. 8 (a) and 8 (b).
If a slit is formed on the top plate 37 at a position corresponding to the slit 36, the adverse effect of the internal stress due to the temperature change can be further suppressed.

Finally, when the drive circuit chip 39 is connected to the individual wiring electrodes 29 and fixed to the substrate 23, the ink supply holes 28 described above are formed in the long side end surfaces 25 (25-1, 25-2). Wiring electrode 29, common electrode 31, heating element 32,
A print head (inkjet head) 40 (40a, 40b) including a partition wall 33, an ink pressurizing chamber 34, an ink flow path 35, a slit 36, a top plate 37, and a discharge nozzle 38
Are completed, thereby completing the head module 41.

As described above, in this embodiment, since the head module is formed using the ceramic substrate, a head module head which is more advantageous in terms of production, such as yield and man-hours, and cost, than the silicon substrate is provided. It is possible to provide. It is preferable that an appropriate protective film is formed on an exposed portion of the individual wiring electrode 29, and that the drive circuit 29 is also sealed with an appropriate resin or the like. Further, a control signal input terminal (not shown) of the drive circuit chip 39 may be connected to a control line (not shown) formed on the substrate 23,
May be connected to a control line (not shown) formed on the FPC connected to the FPC.

As shown in FIG. 1, the head module 41 moves the paper 42 conveyed in the sub-scanning direction indicated by the arrow E in the figure in the vicinity of the top plate 37 from the two rows of ejection nozzles 38 into the mono module. Printing (printing, recording) is performed by discharging color (eg, black) ink. The ink is supplied from an external ink tank or the like to the ink pressurizing chamber 34 via the ink introduction path 27, the ink supply hole 28, and the ink flow path 35.

As described above, the two rows of discharge nozzles 3
The arrangements 8 are formed so as to be shifted from each other in the column direction by の of the arrangement pitch in the column. Therefore, the density (resolution) of the recording dots recorded by the head module 41
Represents the ink droplets ejected from the two rows of ejection nozzles 38,
By arranging and landing on the same line on the recording surface of the paper 42, high-resolution recording can be performed at a density twice the arrangement pitch in the row of the ejection nozzles 38.

FIG. 4 is a diagram for explaining a recording operation and a maintenance operation of the printer using the full array type head module 41 described above. Here, the maintenance includes a process of capping, wiping, and / or priming the ink ejection surface of the print head 40 as a process for maintaining an appropriate ejection performance of the ejection nozzle 38. FIG. 1 shows only the configuration of the main parts necessary for explaining the recording operation and the maintenance operation, and the configurations of the drive system, the paper transport system, and the control system thereof are omitted.

As shown in FIG.
Is provided with rotating shafts 43 fixed to both end surfaces on the short side of the substrate 23. The rotating shafts 43 are supported by a frame of a printer main body (not shown), and are alternately halfway as shown by a double-headed arrow F in FIG. Drive control is performed by a drive unit (not shown) so as to rotate.

FIG. 5 shows a state in which the print head 40a is positioned to the right by rotation of the rotary shaft 43. Therefore, the print head 40a is disposed on the end face facing the print head 40a. 40b is positioned to the left. The right position where the print head 40a is positioned is a recording position, and the left position where the other print head 40b is positioned is a maintenance position.

At one recording position, the sheet 42 is conveyed in the sub-scanning direction indicated by the arrow E, and recording is performed on the sheet 42 by the print head 40a. On the opposite side of the print head 40a at the recording position, a cap member 44-1 is provided so as to be able to advance and retreat in the direction of arrow K with respect to the recording position. The cap member 44-1 covers the ejection surface of one of the print heads 40a at the recording position, for example, while the printing of the entire printer is stopped. The supply of ink from an external ink tank to the ink introduction path 27 is performed via a tube connected to a hole (not shown) provided on the rotating shaft 43.

At the same time, maintenance processing of the print head 40b is performed at the other maintenance position. The maintenance unit 44 is located at the maintenance position.
Priming to the maintenance unit 44 by the discharge nozzle 38 of the print head 40b, or the print head 4 by the maintenance unit 44.
The wiping of the ink ejection surface of 0b, the capping of the ink ejection surface of the print head 40b by the maintenance unit 44, or a combination thereof is performed at a predetermined recording cycle such as the number of recordings.

After the predetermined recording cycle, the rotation of the rotary shaft 43 causes the head module 41 to make a half turn, thereby positioning the print head 40b at the right recording position, and maintaining the print head 40a at the left position. Then, the recording and the maintenance processing described above are performed. As described above, the state in which the half rotation of the head module 41, the subsequent recording, and the maintenance processing proceed simultaneously is repeated, and the recording on the paper proceeds.

That is, the recording operation only stagnates during the half rotation of the head module 41, and the recording is performed by the other print head even during the maintenance process, so that the recording operation is not interrupted for a long time. Recording can be performed at high speed. In the first embodiment, the print head 40 of the head module 41 is a print head that discharges monochromatic ink, that is, a print head that supports only monochrome recording. For example, a head module that forms four or six print heads and supplies four or six colors of ink corresponding to the individual print heads to perform color recording may be formed.

Alternatively, the head module 41, the rotating shaft 43, and the maintenance unit 44 shown in FIG.
As a set, four or six sets may be arranged side by side, and a printer that performs color printing by supplying inks of four or six colors corresponding to each set may be configured.

Further, the cap member 44-1 mounted on the print head located at the recording position when the printer is stopped, sucks and discharges the ink from the print head located at the recording position while the printer is stopped, and removes the print head. It is also possible to omit it by taking a method such as emptying.

In addition, in the above embodiment, two print heads are provided on a pair of opposed end faces of the rectangular parallelepiped base.
However, the present invention is not limited to this. For example, three or four or more print heads may be provided on three or more of the different surfaces of one base. An example of such an embodiment is described below.

FIG. 5 is a diagram showing a configuration and an operation state of a head module according to the second embodiment. As shown in the figure, the head module 45 includes a triangular prism-shaped base 47 made of ceramics and the like rotatably supported on a rotating shaft 46, and long prints formed on each of three surfaces of the base 47. Heads 48a, 48b, and 48c.
The print head 48 includes the head module 41 shown in FIG.
Is substantially similar to a shape obtained by cutting the print head in half for each of the print heads 40a and 40b.

In the figure, the print head 48a is positioned at the recording position immediately to the right of the right side, and performs recording on the sheet 42 conveyed in the sub-scanning direction indicated by the arrow E in the figure. The other print head 48b is positioned at a first maintenance position facing obliquely to the upper left, and is capped by a first maintenance unit 49 dedicated to capping. The other remaining print head 48c is positioned at the second maintenance position facing diagonally downward and leftward, and is set by the second maintenance unit 51 in a state where both priming and wiping are possible. .

The head module 45 makes a 1/3 turn in a counterclockwise direction indicated by an arrow G in the figure at a predetermined cycle,
The print head 48a is at the position of the print head 48b, the print head 48b is at the position of the print head 48c,
8c are positioned alternately with the positions of the print heads 48a, the print heads 48c execute recording, the print heads 48a are capped, and the print heads 48b are primed or wiped, or a wiping and priming maintenance process is performed. Is executed. This is sequentially repeated.

Also in this case, the head module 45
The recording operation only stagnates for a period of three rotations.
Since printing is performed by one print head remaining during the maintenance process, printing can be performed at high speed without interrupting the printing operation for a long period of time while performing a plurality of maintenance processes sufficiently.

FIG. 6 is a diagram showing a configuration and an operation state of a main part of a printer according to the third embodiment. FIG. 2 shows a head module 52 and two maintenance units 53 (53-53), which are main parts of the invention of the printer.
1, 53-2) and papers 42a and 42b being transported and waiting in two paper transport paths (not shown).

The head module 52 shown in FIG.
And is fixed to the frame of the printer main body. With the head module 52 fixed to the printer body in this manner, printing is executed by the two print heads 54a and 54b disposed on the two opposite end surfaces of the head module 52.

First, as shown in FIG.
a is a sheet 42 conveyed in the sub-scanning direction indicated by the arrow H in the figure.
While printing is being performed on a, the maintenance unit 53-1 dedicated to the print head 54a has moved to the retracted position shown in the figure. A maintenance unit 53-2 dedicated to the print head 54b is moved to and adjacent to the other print head 54b, and a predetermined maintenance process is performed. Further, the sheet 42b to be recorded next is conveyed halfway through the dedicated conveyance path by the print head 54b in the sub-scanning direction indicated by the arrow J, and stands by at the standby position.

From this state, the paper 42a is discharged out of the machine and a predetermined printing cycle is reached, so that the print head 54a
The dedicated maintenance unit 53-1 moves to the left as shown by the arrow K in the figure and is positioned at the maintenance position.
The maintenance process is started, the maintenance unit 53-2 dedicated to the print head 54b moves leftward as shown by the arrow L in the drawing and retreats to the retreat position, and the conveyance of the waiting sheet 42b is started, and the print head 54b Starts recording.

When a predetermined number of sheets 42b are recorded and a predetermined printing cycle is reached, the maintenance unit 53-2 dedicated to the print head 54b moves from the retracted position to the maintenance position shown in FIG. The maintenance unit 5 dedicated to the print head 54a
3-1 is retracted from the above-described maintenance position to the retracted position shown in the figure, the conveyance of the waiting sheet 42a is started, and the recording by the print head 54a is started.

As described above, the recording execution and the maintenance process are repeated at a predetermined printing cycle, and
4 (54a or 54b) is performed by the other print head 54 (54b or 54a) during the maintenance processing.
The recording operation only stagnates during the movement period of 3-2, and recording is performed by one print head remaining during the maintenance processing, so that high-speed recording can be performed without interrupting the recording operation for a long period of time. Can be done.

In this case as well, a head module for performing color recording by forming four or six print heads on the long side end surface of the substrate may be used.
Two or two maintenance units 53 may be used as one set, and four or six sets may be arranged in parallel to constitute a printer that performs color printing.

In each of the first to third embodiments, a head module in which a plurality of print heads are integrally provided on one substrate or base is used as a print module. Not limited to the above, equipped with a plurality of print heads that are individually arranged and execute recording separately, when the print head that was recording has entered maintenance processing, the other print head takes over the recording, and The configuration may be different from the above-described configuration as long as the maintenance process and the recording are performed in parallel. An example of a printer having such a configuration will be described below as a fourth embodiment.

FIGS. 7A, 7B and 7C are diagrams for explaining the configuration and operation of the printer according to the fourth embodiment. The figure
(a), (b) and (c) show only the components necessary for explanation,
The other components are not shown. Figures (a), (b),
As shown in (c), the printer 55 has a first print head unit 56 and a second print head unit 57 which can be freely moved to a recording position and a maintenance position by a guide shaft and a drive belt (not shown). , Which is arranged at the center and is circulated clockwise in FIG.
1. A first maintenance unit 62 fixed at both maintenance positions on both sides of the belt 61 for conveying and platen.
And a second maintenance unit 63.

The paper is not particularly shown in the figure.
As shown by the arrow M in (a), the printer body is inserted from the lower left side in the figure, is attracted to the conveyor / platen belt 61, is conveyed to the right in the figure, and is printed while passing through the recording position. , And is discharged U-turn by the driven roller 59.

FIG. 7A shows the first print head unit 5.
6 indicates that recording is being performed at the recording position. During this time, the second print head unit 57 is moved to the second maintenance position on the right by a slide mechanism (not shown), and the second print head unit 57 is moved to the second maintenance position. Maintenance unit 63
Is rested with the cap member 63a.

Next, at a predetermined printing cycle, the first print head unit 56 that has been performing recording is moved to the first maintenance position on the left side by the slide mechanism, as shown in FIG. And the first maintenance unit 6
A predetermined maintenance process is performed with the second cap member 62a covered, and at the same time, the second print head unit 57 moves from the right maintenance position to the recording position to execute recording.

During recording, FIG. 7 (a) and FIG. 7 (b) are repeated. When recording is paused or stopped, as shown in FIG.
Both the first print head 56 and the second print head 57 are rested at their respective maintenance positions with the cap member 62a of the first maintenance unit 62 or the cap member 63a of the second maintenance unit 63 covered.

The present invention is not limited to a thermal ink jet printer, but can be applied to other types of ink jet printers such as a piezoelectric type using a piezo element.

[0073]

As described above in detail, according to the present invention, a plurality of print heads are provided, and when a print head during recording enters a wiping or priming maintenance process, another print head is simultaneously provided. Since printing is continued by the print head, the printing operation can be performed at high speed without stagnation of the printing operation due to the maintenance process.

[Brief description of the drawings]

FIG. 1 is a perspective view of a head module of a printer according to a first embodiment.

FIGS. 2A and 2B are diagrams (part 1) illustrating a manufacturing process sequence of the head module of the printer according to the first embodiment.

FIGS. 3A and 3B are diagrams (part 2) illustrating a manufacturing process sequence of the head module of the printer according to the first embodiment.

FIG. 4 is a diagram illustrating a recording operation and a maintenance operation of the printer according to the first embodiment.

FIG. 5 is a diagram illustrating a configuration and an operation state of a head module including three print heads according to a second embodiment.

FIG. 6 is a diagram illustrating a configuration and operation of a main part of a printer according to a third embodiment.

FIGS. 7A, 7B, and 7C are diagrams illustrating the configuration and operation of a main part of a printer according to a fourth embodiment.

8A is a perspective view showing an ink ejection surface of a conventional thermal roof shooter type print head, and FIG.
It is A 'sectional arrow view.

FIGS. 9A and 9B are diagrams schematically showing two examples of the configuration of a print head of a conventional line type printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Print head 2 Chip board 3 Drive circuit 4 Individual wiring electrode 5 Heating part 6 Common electrode 7 Connection electrode terminal 8 Ink supply groove 9 Ink supply hole 11 (11-1, 11-2, 11-3) Partition 12 Ink pressurization Chamber 13 Top plate 14 Ink flow path 15 Discharge nozzle 16 Nozzle row 17, 20 Print head 18, 21 Head chip 19, 22 Parent substrate 23 Substrate 24 (24-1, 24-2) Main plane 25 (25-1, 25) -2) Long side end surface 26 (26-1, 26-2) Short side end surface 27 Ink introduction path 28 Ink supply hole 29 Individual wiring electrode 31 Common electrode 32 Heat generation part 33 (33-1, 33-2) Partition wall 34 ink pressurizing chamber 35 ink flow path 36 slit 37 top plate 38 discharge nozzle 39 drive circuit chip 40 (40a, 40b) print head 41 head module 4 , 42a, 42b Paper 43 Head holder 44-1 Cap member 44-2 Maintenance unit 45 Head module 46 Head holder 47 Base 48 (48a, 48b, 48c) Print head 49 First maintenance unit 51 Second maintenance unit 52 Head module 53 (53-1, 53-2) Maintenance unit 54 (54a, 54b) Print head 55 Printer 56 First print head unit 57 Second print head unit 58 Drive roller 59 Follower roller 61 Conveyor / platen belt 62 first maintenance unit 62a cap member 63 second maintenance unit 63a cap member

Claims (6)

[Claims] 1. An ink jet printer which performs recording by applying pressure to ink and ejecting the ink from a discharge nozzle in a predetermined direction to land on a sheet of paper, comprising: a plurality of ink jet heads; A maintenance unit that is detachably mounted on the ejection surface and performs a maintenance process for maintaining proper ejection performance of the ejection nozzles; and performs a recording process and a maintenance process by the maintenance unit on the plurality of inkjet heads, respectively. An ink-jet printer, comprising: a drive control means for performing the operation. 2. The inkjet head according to claim 1, wherein each of the plurality of inkjet heads is installed on at least two surfaces of a rotatably supported base, and each of the inkjet heads installed on each of the at least two surfaces includes the inkjet head. 2. The ink jet printer according to claim 1, wherein the rotation of the base moves to a recording position where recording is performed and a maintenance position where maintenance processing is performed. 3. The ink-jet printer according to claim 2, wherein two ink-jet heads are provided, and each of the ink-jet heads is provided on an opposing end face of the rectangular parallelepiped base. 4. An ink jet head comprising two ink jet heads,
The two ink-jet heads are respectively installed on opposing end faces forming a rectangular parallelepiped of a fixed base, paper transport paths are provided for respective recording positions of the two ink-jet heads, and the maintenance means is provided. 2. An ink jet printer according to claim 1, wherein said maintenance means is provided for each of said ink jet heads, and said maintenance means is movably disposed between a retreat position during printing and a maintenance position. 5. The ink jet head according to claim 1, wherein the ink jet head is a full array head including a discharge nozzle array corresponding to substantially the entire recording area width of a sheet.
Or the inkjet printer according to 4. 6. The ink jet printer according to claim 1, wherein the maintenance process is a process for performing at least one of capping, wiping, and priming.