JP2003048315A - Ink jet recorder and its adjusting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large ink jet recorder having high recording efficiency and accuracy, and its adjusting method. SOLUTION: The ink jet recorder is provided with a plurality of head units 10 each comprising a recording head 6 carried on a carriage 1 and reciprocated in the widthwise direction of a recording medium in order to eject ink drops toward the recording medium, and a sub-tank 7 carried on the carriage together with the recording head such that the position can be adjusted and supplying ink to the recording head while being supplied with ink from a main tank 9. Since the difference of head between the ink level in the sub-tank and the nozzle forming face of the recording head can be adjusted, ink ejection from the nozzle can be made uniform even if each recording head can not be adjusted finely when the driving waveform of the ink jet recorder is standardized, for example, resulting in further enhancement of recording accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus in which a sub tank for supplying ink to a recording head is mounted on a carriage and a method of adjusting the same, and in particular, a plurality of head units having a recording head and a sub tank are provided. The present invention also relates to an inkjet recording apparatus and an adjusting method thereof.

[0002]

2. Description of the Related Art Ink jet printers, which are one of ink jet recording apparatuses, generate relatively small noise during printing and can form small dots with high density. Is used for. For example, a serial printing type inkjet printer is generally mounted on a carriage and moves an inkjet recording head in the width direction of a recording sheet, and moves the recording sheet in a direction orthogonal to the moving direction of the recording head. Paper feeding means is provided,
Printing is performed by ejecting ink droplets from the recording head onto the recording sheet based on the print data.

Ink jet printers provided for the office or business need to be capable of printing relatively large volumes. For this reason, a large-capacity main tank for each color is arranged on the printer main body side, and each color is connected to each main tank via the ink supply tube and each color connected via the recording head and the ink supply tube. A type has been proposed in which each sub-tank is arranged on a carriage, ink is replenished from each main tank to each sub-tank, and ink is further supplied from each sub-tank to a recording head (for example, Japanese Patent Laid-Open No. Hei 11). -161880, JP-A-11-2406
74, JP-A-11-240914, and JP-A-6-121134).

[0004]

By the way, in recent years, there is an increasing demand for a large ink jet printer capable of printing on a large paper surface. In such an ink jet printer, the number of nozzles in the recording head is increased in order to improve throughput. However, it is difficult to form a large number of nozzles with uniform characteristics in one recording head, and there is a limit to improvement of printing accuracy.

The present invention has been made in view of the above problems, and an object thereof is to provide a large-sized ink jet recording apparatus having high recording efficiency and recording accuracy and an adjusting method thereof.

[0006]

In order to achieve the above object, an ink jet recording apparatus according to claim 1 of the present invention comprises:
A recording head, which is mounted on a carriage and reciprocates in the width direction of the recording medium, ejects ink droplets onto the recording medium, and is mounted on the carriage together with the recording head so that the position of the recording head is adjustable, and ink is supplied from a main tank A plurality of head units, each of which has a sub-tank that receives the ink and supplies the ink to the recording head, are arranged. As a result, a large number of independent head units are arranged on the carriage. Therefore, head units having certain characteristics are selected and mounted, or head units having deteriorated characteristics have heads having predetermined characteristics. You will be able to replace it with a unit. Therefore, the throughput for a large-sized recording medium can be improved, and the recording accuracy can be improved and maintained. Furthermore, since the head difference between the ink surface in the sub tank and the nozzle formation surface of the recording head can be adjusted, fine adjustment can be performed for each recording head when considering common drive waveforms for ink jet recording devices. Even if it is not necessary, the amount of ink ejected from the nozzles can be made uniform, and the recording accuracy can be further improved.

According to a second aspect of the invention, in the ink jet recording apparatus according to the first aspect, the position of the sub-tank is adjusted during recording on the recording medium by the recording head. This makes it possible to adjust the head difference between the ink surface in the sub-tank and the nozzle formation surface of the recording head, especially during the recording process on the upper and lower ends of the recording medium, so that the amount of ink ejected from the nozzles can be made uniform. Therefore, the recording accuracy can be further improved.

According to a third aspect of the present invention, in the ink jet recording apparatus according to the first or second aspect, the position of the sub-tank is finely adjusted at the stage of assembly to the carriage. As a result, the amount of ink ejected from the nozzles can be made uniform to some extent in the initial stage, and the adjustment range of the position of the sub tank thereafter can be widened, and the dynamic pressure adjustment by the sub tank position during printing can be performed over a wide range. It can be performed stably.

According to a fourth aspect of the invention, in the ink jet recording apparatus according to the fourth aspect, the fine adjustment of the position of the sub-tank is performed according to the drive waveform proper voltage displayed for each recording head. It has a feature. As a result, the recording head with the highest drive waveform appropriate voltage, that is, the recording head that does not eject much ink at the same voltage, is used as a reference so that the ink surface in the sub-tank of another recording head is ejected so that the appropriate ink amount can be ejected. The head difference can be adjusted by lowering it from the nozzle forming surface. Since the change in the dynamic pressure when the height of the sub-tank is changed is larger in the recording head having the lower proper voltage, the number of sub-tanks needs to be adjusted less. In addition, since the adjustment is performed by lowering the sub tank, ink does not drip from the nozzle due to the adjustment. The same applies to adjustment during printing because the sub-tank is lowered.

According to a fifth aspect of the present invention, in the ink jet recording apparatus according to the fourth aspect, storage means for storing the drive waveform appropriate voltage for each recording head, and the storage means for each recording head from the storage means. It is characterized by comprising an adjusting means for reading the drive waveform proper voltage and finely adjusting the position of the sub tank. As a result, the head difference between the ink surface in the sub tank and the nozzle forming surface of the recording head can be automatically adjusted, so that the optimum print output can be obtained even if the print duty changes.

According to a sixth aspect of the present invention, in the ink jet recording apparatus according to the fifth aspect, a table is provided for storing the adjustment value of the position of the sub tank corresponding to the drive waveform appropriate voltage for each of the recording heads. It is characterized in that the adjusting means makes a fine adjustment based on the adjustment value of the position of the sub tank selected from the table according to the drive waveform appropriate voltage for each of the recording heads read from the storage means. As a result, the number of nozzles used at the time of recording processing, especially at the upper and lower ends of the recording medium, is smaller than in the normal state, and the variation in dynamic pressure in the flow path increases the ink discharge weight per nozzle, There is an adverse effect such that the color becomes darker than that in normal recording. Since it is possible to quickly adjust the position of the sub-tank to the optimum position by referring to the table in which the adjustment value is written according to the nozzle, it is possible to improve the recording accuracy of the upper and lower ends.

According to a seventh aspect of the invention, in the ink jet recording apparatus according to any one of the fourth to sixth aspects, the fine adjustment of the position of the sub-tank is performed by the recording head having a high drive waveform appropriate voltage. As a standard, it is characterized in that the head is lowered. As a result, the water head pressure acting on the ink liquid surface is constantly lowered, so that it is possible to avoid ink leakage that occurs due to raising the water head. Also, with a recording head with a high drive waveform appropriate voltage,
Since the change in the ink discharge weight due to the head difference is small, many changes in the water head are necessary for a small change in the ink discharge weight, that is, the range of motion is large, but in this case, the range of motion is minimized. Can be suppressed.

According to an eighth aspect of the present invention, in the ink jet recording apparatus according to any one of the first to seventh aspects, each head unit includes the recording heads and the recording heads for all colors used for color printing. It is characterized by having a sub tank. As a result, since all the colors are included in one head unit when the head unit is built, positioning adjustment within the head unit is not necessary, and positioning adjustment may be performed for each head unit, reducing man-hours. be able to.

According to a ninth aspect of the invention, in the ink jet recording apparatus according to any one of the first to eighth aspects, a common drive signal is supplied to each of the recording units. As a result, the circuit can be shared and the cost can be reduced.

In the invention according to claim 10, claims 1 to 9 are provided.
The ink jet recording apparatus according to any one of the above 1 to 3, wherein a plurality of the main tanks are provided at different heights. Even when a plurality of recording heads are provided and the heights of the sub-tanks greatly differ, the head difference between the sub-tank and the main tank can be made uniform, so that ink can be stably supplied to the sub-tank for printing.

According to the invention of claim 11, claims 1 to 1
0. In the ink jet recording apparatus according to any one of 0, a cap unit that seals a nozzle forming surface of each recording head and sucks and discharges the ink from the recording head is provided for each recording head. It is characterized by being. Further, in the invention according to claim 12, in the ink jet recording apparatus according to any one of claims 1 to 11, the first flow path opening / closing means for controlling the opening / closing of the ink flow path around each of the recording heads is the above-mentioned. It is characterized in that it is provided for each ink flow path. As a result, cleaning can be performed for each recording head, and defective nozzles can be reliably and efficiently recovered.

According to a thirteenth aspect of the present invention, in the ink jet recording apparatus according to the twelfth aspect, the first flow path opening / closing means is disposed on the cap unit side. Further, in the invention according to claim 14, in the ink jet recording apparatus according to any one of claims 11 to 13, negative pressure generating means for setting a negative pressure to the ink flow path is provided. It has a feature. As a result, a negative pressure is not generated in the recording head that is not the cleaning target, so that the meniscus formed in the nozzle can be prevented from being destroyed. Particularly, by using a desiccator as the negative pressure generating means, a decompression curve does not occur, so that the cleaning time can be shortened.

According to a fifteenth aspect of the present invention, in the ink jet recording apparatus according to the fourteenth aspect, a plurality of the negative pressure generating means are arranged, and a plurality of negative pressure generating means are provided for each ink flow path on the negative pressure generating means side. It is characterized in that two flow path opening / closing means are provided. This makes it possible to adjust the negative pressure for each recording head, so that the cleaning time can be shortened and defective nozzles can be effectively used even when a tube pump or the like is used as the negative pressure generating means in addition to the desiccator. Can be restored to.

According to the invention of claim 16, claims 1 to 1
5. The ink jet recording apparatus according to any one of 5 above, further comprising a wiper unit which is movable in an array direction of the recording heads and wipes a nozzle forming surface of the recording heads arranged in a movable region. It is characterized by being. As a result, the space occupied by the wiper unit with respect to the device can be reduced, so that the cost increase due to the increase in size of the device can be suppressed.

According to a seventeenth aspect of the present invention, there is provided an ink jet recording apparatus adjusting method, wherein the recording head is mounted on a carriage and reciprocates in a width direction of the recording medium to eject ink droplets onto the recording medium. An inkjet recording apparatus having a plurality of head units, which are mounted together with a recording head on the carriage in a positionally adjustable manner, receive a supply of ink from a main tank, and have a sub-tank that supplies the ink to the recording head. The adjusting method is characterized in that the position of the sub-tank is adjusted during recording on the recording medium by the recording head.

According to an eighteenth aspect of the present invention, in the method of adjusting an ink jet recording apparatus according to the seventeenth aspect,
The position of the sub-tank is finely adjusted during the assembly of the sub-tank. According to a nineteenth aspect of the present invention, in the method of adjusting the ink jet recording apparatus according to the eighteenth aspect, the fine adjustment of the position of the sub-tank is performed according to the drive waveform proper voltage displayed for each of the recording heads. It has a feature.

According to a twentieth aspect of the invention, in the method of adjusting the ink jet recording apparatus according to the nineteenth aspect,
Storage means for storing the drive waveform proper voltage for each recording head; adjusting means for reading the drive waveform proper voltage for each recording head from the storage means to finely adjust the position of the sub tank; A table for storing the adjustment value of the position of the sub-tank corresponding to the drive waveform proper voltage for each, the adjusting means, according to the drive waveform proper voltage for each of the recording head read from the storage means, the table The fine adjustment is performed based on the adjustment value of the position of the sub tank selected from.

According to a twenty-first aspect of the invention, in the method for adjusting an ink jet recording apparatus according to the nineteenth or twentieth aspect, the fine adjustment of the position of the sub-tank is based on the recording head having a high drive waveform proper voltage. The feature is that the head is lowered. Claim 2
The invention according to 2 is characterized in that the adjusting method for an ink jet recording apparatus according to any one of claims 17 to 21 is constructed in a computer-executable program.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view showing a structural example of an ink jet printer according to an embodiment of an ink jet recording apparatus of the present invention. The inkjet printer 200 shown in FIG. 1 is a large inkjet printer capable of printing even a relatively large size printing paper (roll paper R) such as JIS A0 size or JIS B0 size. Then, the paper feeding unit 210, the printing unit 220,
The paper discharge section 230 is arranged from the upper side of the printer body 250 toward the lower side of the leg section 240.

The paper feeding section 210 is provided with a roll paper holder 211 on which the roll paper R before printing can be set. The roll paper holder 211 includes a spindle 212 that holds the roll paper and a pair of spindle receivers 213 and 214 to which the spindle 212 can be attached / detached and suspended. Two roll holders are provided above the printer body 250. Support pillar 2
It is arranged between 15 units. After the roll paper R is mounted in the center of the spindle 212, the spindle receiver 21
3, 214, and is rotatably supported by a shaft.

The paper discharge section 230 has a take-up holder 231 which can take up the roll paper R after printing. The take-up holder 231 includes a spindle 232 for taking up the roll paper R on which printing has been completed, and a pair of spindle receivers 233 and 234 to which the spindle 232 can be attached / detached and suspended. It is arranged between two support columns 242 each having a roller 241. Spindle 2
Both ends of 32 are attached to spindle receivers 233 and 234, and are rotatably supported by shafts by driving means (not shown).

The printing unit 220 is housed in the printer body 250 and is covered by an upper lid 220a and a front lid 220b attached to the upper surface and the front surface of the printer body 250, the details of which will be described with reference to FIG. . FIG. 2 is a partial cross-sectional side view of the inkjet printer 200 shown in FIG. A paper transport path from the paper feed unit 210 to the paper discharge unit 230 via the printing unit 220 is provided so as to be inclined from the upper rear surface side to the lower front surface side of the inkjet printer 200.

On this paper transport path, a paper feed guide 221, a contacting / separable paper feed roller 222 and a driven roller 223, which are arranged facing each other, and a plurality of rollers mounted on the carriage 1, are arranged in this order from the paper feed section 210 side. Inkjet recording head 6, printing stage 224 arranged opposite recording head 6, ejection guide 225, and ejection guide 22
5, a paper discharge roller 226 is disposed so as to face the No. 5 unit.

The paper feed guide 221, the printing stage 224,
The paper ejection guides 225 act as a paper transport surface and are formed flat. Therefore, the paper feed guide 22
The roll paper R from 1 to the paper discharge guide 225 via the printing stage 224 is conveyed while being flat.

Here, FIG. 3 is a top view of the printing unit 220,
4 is a plan view showing the periphery of the carriage 1, and FIG.
2 is a cross-sectional side view taken along line AA of FIG. As shown in FIG. 3, the carriage 1 is guided by the scanning guide member 4 via the timing belt 3 driven by the carriage motor 2 and is in the longitudinal direction of the printing stage 224, that is, the main scanning direction which is the width direction of the recording paper. It is supposed to be moved back and forth.

As shown in FIGS. 3 to 5, the carriage 1 has a head unit 10 having a recording head 6 (not shown in FIG. 3) and a sub-tank 7 for supplying ink to the recording head 6. But 4 in the main and sub-scanning directions
They are arranged in a unit of 4 (5 in part). It should be noted that the number of arrays of the head units 10 is not particularly limited to 4 × 4 (some 5), and any number of arrays may be used. As shown in FIG. 1, a cartridge holder 8 arranged at the end of the apparatus main body is equipped with a main tank 9 for supplying ink to the sub tank 7.

As shown in FIGS. 4 and 5, each recording head 6 is mounted on the surface side of the carriage 1 facing the paper feed member 5, and each sub-tank 7 is a carriage above the corresponding recording head 6. It is mounted on 1. In this example,
Since the number of sub-tanks 7 is large relative to the space on the carriage 1, each sub-tank 7 is separately mounted on two stages of plates 1 a and 1 b arranged on the carriage 1.
The plates 1a and 1b are not limited to two stages, and one or three or more stages of plates can be provided depending on the number of sub-tanks 7. Further, the sub tank 7 and the head unit 10 may be integrated and fixed on the carriage 1. This further facilitates exchange maintenance.

Each sub-tank 7 is provided with an actuator 17 for moving the sub-tank 7 in the direction of arrow a, that is, in the height direction. The actuator 17 is provided with the ink surface in the sub tank 7 and the recording head 6.
It is arranged to adjust the head pressure caused by the head difference from the nozzle forming surface and to adjust the ink discharge weight of the recording head 6. The actuator 17 is composed of, for example, a ball screw / nut having a motor, an air cylinder, a hydraulic cylinder, or the like. Further, a sensor using a Hall element that adjusts the ink surface can be used as the head difference adjusting means.

By performing the adjustment by the actuator 17 during printing, it is possible to make the amount of ink ejected from the nozzles uniform, particularly during the printing process on the upper and lower ends of the recording paper, and further improve the printing accuracy. it can. Further, since fine adjustment by the actuator 17 is performed when the sub-tank 7 is incorporated in the carriage 1, the amount of ink ejected from the nozzles can be made uniform to some extent in the initial stage. Therefore, the dynamic pressure can be stably adjusted over a wide range depending on the position of the sub tank during printing. Further, in the present embodiment, one sub-tank 7 is provided with the actuator 17, but the same number as the number of sub-tanks constituting each color may be provided. As a result, the height can be adjusted for each color according to the ink surface of the sub-tank, so that the printing quality can be further improved.

Here, since the dynamic pressure of the recording head 6 is different for each head, as shown in FIG. 6, the inclination of the head difference h-ink discharge weight Iw is also the drive waveform proper voltage VH of the recording head 6.
Depends on the head ID determined at the time of manufacture. The drive waveform appropriate voltage VH is a voltage that is solid, that is, the voltage at which the ink weight is optimal during full-duty printing. Therefore, the recording heads 6 in the areas A, B, and C are selectively used, and the adjustment value of the head difference h is selected to adjust the position of the sub tank 7. As a result, since the characteristics of the print heads 6 can be made uniform, the print heads 6 to be incorporated in the carriage 1 can be selected even if the characteristics of the print heads 6 vary greatly, and the head driver can be shared. Therefore, the cost can be significantly reduced.

Further, when the recording head 6 having the lowest drive waveform proper voltage VH, that is, the recording head 6 at which the same voltage produces a large amount of ink, is used as a reference, the other recording heads 6 have the same voltage and discharge a small amount of ink. It is necessary to adjust the head difference h in the direction of raising it from the reference position. Regarding the nozzle position and the height of the ink surface of the sub tank 7, if the nozzle position is not higher, the ink will drop. Therefore, sub tank 7
There is a limit to the height that can be raised. On the other hand, for example, in FIG.
As shown in, when the recording head 6 having the highest drive waveform proper voltage VH, that is, the recording head a at which the same voltage does not leave a large amount of ink, is used as a reference, the head difference h may be adjusted in the direction of lowering from the reference position. Since the change in the dynamic pressure when the height of the sub-tank 7 is changed is larger in the recording head b having a lower appropriate voltage, less adjustment of the sub-tank 7 is required. Further, since the adjustment is performed by lowering the sub tank 7, the ink does not drip from the nozzle due to the adjustment. The same applies to the adjustment at the time of printing because the sub-tank 7 is lowered.

Particularly, since the number of nozzles used when performing the upper and lower end processing on the recording paper is smaller than the number of nozzles normally used, the dynamic pressure of the flow path is reduced, and the ink discharge weight is about 5% to 7%. Since it increases, it is possible to adjust the position of the sub tank 7 by referring to the table by preparing a table in which the water head adjustment value H is preliminarily recorded according to the number of nozzles.

Although the actuator 17 is provided as a means for adjusting the water head difference between the ink surface in the sub tank 7 and the nozzle forming surface of the recording head 6, the present invention is not limited to this, and a long hole is formed in the sub tank 7. Alternatively, the sub-tank 7 may be provided, and the height of the sub-tank 7 may be determined and then screwed to the carriage 1. In addition, Hall elements 33a and 33b provided in the sub tank 7 described later (see FIG. 9).
A means for changing the position of may be provided.

FIG. 8 is a sectional view showing the details of the recording head 6. As shown in FIG. 8, the recording head 6 has a flow path unit 161 and a piezoelectric vibration unit 162. The flow path unit 161 includes a nozzle plate 163 having a plurality of nozzle openings 163a formed as a nozzle row, a pressure generation chamber 164a communicating with the nozzle openings 163a, and a reservoir 164c for supplying ink to the pressure generation chambers 164a. The flow path forming substrate 164 and the elastic plate 165 that abuts on the tip of each piezoelectric vibrator 162a in the longitudinal vibration mode of the piezoelectric vibration unit 162 to expand or contract the volume of the pressure generating chamber 164a are integrally laminated. Has been done.

The piezoelectric vibrating unit 162 is connected to a flexible cable 166 for transmitting a drive signal from the outside, and then housed and bonded in a housing chamber 167a of a holder 167 formed by injection molding of a polymer material. The holder 167 and the flow path unit 161 are fixed with an adhesive. Holder 16
In FIG. 7, an ink guide path 167b communicating with an external ink tank (not shown) is formed, the tip of which is connected to the ink introduction port 167c of the flow path unit 161, and the ink from the sub-tank 7 enters the flow path unit 161. Supplied. A frame 168 that also serves as a shield is inserted into the integrated holder 167 and the flow path unit 161 on the side of the nozzle plate 163 to form the recording head 6.

Each piezoelectric vibrator 162a in the longitudinal vibration mode which constitutes the piezoelectric vibration unit 162 is, for example, although not shown, sandwiched between electrodes serving as one pole and electrodes serving as the other pole via a piezoelectric material. , One electrode is exposed on the front end side and the other electrode is exposed on the rear end side, and each end face is connected to the segment electrode and the common electrode and has a piezoelectric constant d31. The piezoelectric vibrating unit 162 is fixed to the fixed substrate 169 so as to match the arrangement pitch of the.

Each piezoelectric vibrator 1 of the piezoelectric vibration unit 162
The segment electrode and the common electrode (not shown) of 62a are connected to the conductive pattern for driving signal transmission of the flexible cable 166 via the solder layers, respectively. As the drive signal, a common signal is supplied to each of the recording heads 6, so that the landing position deviation of the ink droplets of each recording head 6 can be adjusted independently.

Inkjet printer 20 in this example
Since 0 is a model that uses six color inks of black, yellow, magenta, light magenta, cyan and light cyan, as shown in the enlarged plan view of FIG. 2 rows × 3 heads 6a in which three nozzle rows 6n are combined
It has a configuration of b, 6 cd, and 6 ef.

2 rows × 3 heads 6ab, 6cd, 6
The number of print heads is not limited to the print head 6 of ef, and any number of print heads can be used. As shown in FIG. 3, the sub-tank 7 and the main tank 9 have six tanks 7 corresponding to the respective inks in order to temporarily store the six color inks therein.
It has a configuration including a to 7f and 9a to 9f.

As shown in FIGS. 3 and 5, each recording head 6 and each sub-tank 7a to 7f are connected by an ink supply tube 11. As shown in FIG. 3, each sub-tank 7a to 7f and each main tank are connected. An ink supply tube 12 is connected to the tanks 9a to 9f. As a result, the six color inks in the main tanks 9a to 9f are transferred to the sub tanks 7a to 7f via the ink supply tube 12.
The six color inks in each sub tank 7a to 7f are supplied to each recording head 6 through the ink supply tube 11.

As described above, when the head unit 10 is built, all the colors used for color printing, that is, the above six colors are included in one head unit, so that the recording head 6 is included in one head unit. It suffices that the sub-tank 7 and the sub-tank 7 are reliably positioned, and it is only necessary to adjust the positioning for each head unit 10.

It should be noted that all the colors used for color printing are not limited to the above six colors, and for example, four colors of black, yellow, magenta, and cyan or black, dark yellow, yellow, magenta, light magenta, It is also applicable to seven colors of cyan and light cyan, black, light black, yellow, magenta, light magenta, cyan and light cyan.

As described above, since the head unit 10 having a large number of recording heads 6 and sub-tanks 7 is arranged on the carriage 1, the throughput for a large-sized recording medium can be improved. Further, since each head unit 10 is independent, it is possible to select and install the recording heads 6 having the characteristics of each recording head 6 on the carriage 1, and further, there is a difference in the characteristics of each recording head 6. However, since the characteristics of the recording heads 6 can be made uniform by adjusting the head difference with the sub-tanks 7, uniform recording image quality can be obtained.
Further, when the characteristics of the recording head 6 are deteriorated, the head unit 10 having the recording head 6 having a predetermined characteristic can be easily replaced, so that the maintenance work is facilitated and the recording accuracy is high. You can continue to maintain at.

As shown in FIG. 3, a cap unit 15 is arranged in a non-printing area (home position) on the movement path of the carriage 1. In this cap unit 15, a cap member 15a formed of a flexible material such as rubber capable of sealing the nozzle forming surface of each recording head 6 is provided with heads 6ab, 6cd of each recording head 6.
A plurality (3 × 4 × 4) in this example are arranged corresponding to the 6 ef arrangement. As a result, when the carriage 1 moves to the home position, the nozzle forming surface of each recording head 6 is sealed by each cap member 15a on the cap unit 15 that follows this movement, and the inkjet printer 200 pauses. It is possible to prevent the nozzle openings of the recording heads 6 from being dried.

The cap is not limited to one head and one cap, and may be, for example, three heads and one cap. In this example, each head 6ab, 6cd, 6ef is 2
The ink is a set of colors, and two colors of ink are mixed in each cap member 15a at the time of regular flushing. Therefore, it is possible to prevent solidification that occurs when one color is used.

As shown in FIG. 3, the cap unit 15
A wiper unit 16 formed of an elastic material such as rubber and having a drive stroke in the sub-scanning direction shown by an arrow S in the drawing is disposed on the side of the printing area adjacent to. As a result, the nozzle forming surfaces of the plurality of recording heads 6 can be selectively wiped and cleaned efficiently.

Further, since the space occupied by the wiper unit 16 in the ink jet printer 200 can be reduced, it is possible to suppress an increase in cost due to an increase in the size of the ink jet printer 200. Although the wiper unit 16 is configured to also wipe the plurality of recording heads 6 in the moving area, the present invention is not limited to this, and each of the heads 6ab, 6cd, 6ef or each recording head 6 is wiped. It may be configured for use.

FIG. 9 is a diagram schematically showing an ink supply system mounted on the ink jet printer 200 of FIG. Note that FIG. 9 shows the configuration for one color for convenience. As shown in FIG. 9, the pressurized air generated by the pressure pump 21 is supplied to the pressure adjusting valve 22, and the pressurized air whose pressure is adjusted by the pressure adjusting valve 22 is supplied to the pressure detector 2.
3 is supplied to the main tank 9.

Here, the main tank 9 has an outer shell formed in an airtight state, and an ink pack 24 made of a flexible material in which ink is sealed is housed inside the main tank 9. A space formed by the outer contour of the main tank 9 and the ink pack 24 constitutes a pressure chamber 25, and pressurized air is supplied into the pressure chamber 25 via the pressure detector 23. ing.

As a result, the ink pack 24 housed in the main tank 9 receives pressure from the pressurized air, and acts to generate an ink flow from the main tank 9 to the sub tank 7. Therefore, the ink pressurized in the main tank 9 is supplied to the sub tank 7 mounted on the carriage 1 via the ink supply valve 26 and each ink supply tube 12.

Here, the sub-tank 7 has a float member 31 arranged therein, and a permanent magnet 32 is attached to a part of the float member 31. Magnetoelectric conversion elements 33a and 33b typified by Hall elements are mounted on the substrate 34 and attached to the side wall of the sub tank 7. As a result, the permanent magnet 3 is moved in accordance with the floating position of the float member 31 according to the amount of ink in the sub tank 7.
Lines of magnetic force due to 2 act on the Hall elements 33a and 33b.

Therefore, the Hall elements 33a, 33
The amount of ink in the sub tank 7 can be detected by the electrical output of b. For example, when the amount of ink in the sub-tank 7 becomes small, the position of the float member 31 housed in the sub-tank 7 moves in the gravity direction, and the position of the permanent magnet 32 also moves in the gravity direction accordingly. Therefore, the Hall elements 33 a, 33 due to the movement of the permanent magnet 32
The ink supply valve 26 is opened by the electrical output of b, and the ink pressurized in the main tank 9 is delivered to the sub tank 7 in which the ink amount has decreased.

When the amount of ink in the sub tank 7 reaches a sufficient amount, the Hall element 33a,
The ink supply valve 26 is closed based on the electrical output of 33b. By repeating such a process, the ink is supplied intermittently from the main tank 9 to the sub tanks 7, and the ink is always stored in each sub tank 7 in a substantially constant range. .

In this way, the ink pressurized by the air pressure in the main tank 9 is replenished to the sub tank 7 based on the electrical output based on the position of the float member 31 arranged in the sub tank 7. As a result, the ink supply response can be improved, and the amount of ink stored in the sub tank 7 can be appropriately managed.

Ink is supplied from the sub-tank 7 to the recording head 6 through a valve unit 35 as a flow path opening / closing means and an ink supply tube 36 connected to the valve unit 35. Then, based on print data given to an actuator (not shown) of the recording head 6, ink droplets are ejected from the nozzle openings 6a on the nozzle forming surface of the recording head 6.

Here, the recording heads 6 for all colors and the sub-tanks 7 are both integrally formed, and the ink supply tubes 36 of the recording heads 6 for all colors of the integrated structure are arranged near the valve unit 35. It is configured to be detachable from the carriage 1 by being separated by a joint. As a result, each recording head 6 can be removed from the carriage 1 for easy maintenance.

To the cap unit 15, one end of a suction tube 37a, to which a plurality of suction pumps 37 such as desiccators, which are negative pressure generating means, are connected, is connected. And the cap member 1 in this suction tube 37a
On the 5a side, the valve unit 1 which is the first flow path opening / closing means
5V is connected, and a valve unit 37V that is a second flow path opening / closing means is connected to each suction pump 37 side of the suction tube 37a.

As a result, a negative pressure by the suction pump 37 is applied to each of the heads 6ab, 6cd, 6ef of each recording head 6, and the heads 6ab, 6cd, 6e of each recording head 6 are actuated.
A cleaning process of sucking the ink from f and discharging it to the waste liquid tank 38 can be performed. Especially some heads 6
When defective nozzles occur in ab, 6cd, and 6ef, by opening the valve unit 15V communicating only with the corresponding heads 6ab, 6cd, and 6ef, the defective nozzle can be reliably and efficiently recovered, and good Since no negative pressure is generated in the nozzle, it is possible to prevent the meniscus formed in the nozzle from being destroyed. In addition, wasteful ink consumption can be prevented by the selective cleaning process.

Further, since a plurality of suction pumps 37 are connected, it is possible to appropriately change the negative pressure generation force by selecting the valve unit 37V to be opened. You can switch to and perform fine cleaning. Further, since the desiccator is used as the suction pump 37, the decompression curve does not occur, and the cleaning time can be shortened. A tube pump or the like may be used as the negative pressure generating means as well as the desiccator. Further, a plurality of negative pressure generating means for generating the same negative pressure may be arranged, or a plurality of negative pressure generating means for generating different negative pressure may be arranged.

If the valve unit 15V is closed and the inside of the cap member 15a is filled with ink by flushing when the power of the ink jet printer 200 is turned off, the moisturizing effect can be secured and clogging by ink can be prevented. be able to. In this example, each of the heads 6ab, 6cd, and 6ef has a set of two colors, but the nozzles are arranged in a staggered manner, for example, so that the cleaning process can be performed more effectively. You can

Further, as shown in FIG. 10, a print stage 224 having a plurality of small holes 224a perforated on the sheet conveying surface is connected to one end of the suction tube 37a to which the plurality of suction pumps 37 are connected. . Then, on the side of the printing stage 224 in the suction tube 37a,
The valve unit 224V which is the third flow path opening / closing means is connected.

As a result, a negative pressure generated by the suction pump 37 is generated in the small hole 224a of the printing stage 224, and the roll paper R on the printing stage 224 is sucked to print the printing stage 2
By sticking to the 24th surface, the roll paper R can be held in a flat state. Therefore, the conveyance accuracy can be improved and the printing can be performed with higher accuracy.

Further, for example, when the material to be printed is not an air-permeable material such as paper but an air-impermeable material such as a plastic film, there is a risk that the printing stage 224 may stick to the surface of the printing stage 224 at the time of suction to cause a transport failure. is there. At this time, by selecting the valve unit 37V to be opened, the negative pressure generation force can be changed as appropriate, so that sticking during suction can be prevented and the conveyance accuracy of the printing material can be improved. it can. in this way,
By changing the generated force according to the type of printed material, it is possible to stably convey the printed material. Alternatively, the pump 37 may be shared and a regulator may be provided between the pump 37 and the valve 37V. The pressure can be selected according to the regulator. By using the common pump 37, space saving and low cost can be achieved.

In this way, the ink is sucked from the recording head 6 and discharged to the waste liquid tank 38 during the cleaning process, and the roll paper R on the printing stage 224 is sucked.
Paper R that sucks in and sucks onto the printing stage 224 surface
The suction of the valve unit 15 with one suction pump 37.
Since V, 224V, and 37V can be switched automatically or manually, space can be saved and cost can be reduced.

11 to 13 are views showing an embodiment of the sub-tank 7, and FIG. 11 omits a part of the construction of the sub-tank 7, and is a perspective view of the sub-tank 7 viewed from one side, FIG.
Is a perspective view seen from the same direction, and FIG. 13 is a rear view seen from the back surface direction. The sub-tank 7 is formed in a substantially rectangular parallelepiped shape and has a flat shape as a whole. The outer shell of the sub-tank 7 is composed of a box-shaped member 41 integrally formed with a side wall 41a and a peripheral side wall 41b continuous with the side wall 41a. The member 42 (see FIG. 10) is attached in close contact with the heat welding means, and the ink storage space 43 is formed inside the box member 41 and the film member 42.

Then, one side wall 4 constituting the box-shaped member 41
A support shaft 44 projecting from the ink storage space 43 toward the ink storage space 43 is integrally formed with the box-shaped member 41. The float member 31 has a gravity center in the ink storage space 43 with the support shaft 44 as a rotation center. It is arranged to be movable. In this embodiment, the support shaft 44 is arranged in the vicinity of the horizontal end of the ink storage space 43, and the float member 31 includes the support shaft 44.
Is integrally formed on the movable free end side of the support arm member 45 which is movable around the rotation center.

Then, as shown in FIG. 12, a permanent magnet 32 is attached to the free end side of the support arm member 45. The permanent magnet 32 is provided when the support arm member 45 is in a substantially horizontal state. The sub-tank 7 should be located near the other end of the ink storage space 43 in the horizontal direction.
Hall element 3 mounted on the substrate 34 attached to the side wall of the
It is configured to be closest to 3a and 33b.

The hall elements 33a and 33b are inserted into the positioning recess 41c formed in the side wall of the sub tank 7. By forming this positioning recess 41c, the side wall of the sub tank 7 is made thinner. The moving path of the permanent magnet 32 attached to the float member 31 and the Hall elements 33a and 33b are configured to be closer to each other.

On the other hand, the sub-tank 7 has a lower portion in the direction of gravity, that is, the peripheral side wall 41b in this embodiment.
Has an ink supply port 46 formed at the bottom thereof, and is configured to supply ink from the main tank 9 into the ink storage space 43 via the ink supply tube 12 connected to the ink supply port 46. There is. By forming the ink supply port 46 in the sub-tank 7 at the lower portion in the direction of gravity, the ink from the main tank 9 is supplied from the bottom of the ink storage space 43. Therefore, the ink is supplied to the inside of the ink storage space 43. In order to prevent bubbling of ink in the above, consideration is given.

Further, in the sub-tank 7, in a portion avoiding the moving regions of the float member 31 and the support arm member 45,
Plural rib members 47 are arranged to reduce the degree of ink waviness in the sub-tank 7 as the carriage 1 moves. In this embodiment, the rib member 4
Reference numeral 7 denotes one side wall 41 of the box-shaped member 41 forming the sub tank 7.
The one side wall 41a is integrally formed so as to project from the a toward the ink storage space 43, but it may be formed separately.

The presence of the rib member 47 can reduce the degree of ink waviness in the sub tank 7, thereby improving the accuracy of detecting the amount of ink stored in the sub tank 7 by the Hall elements 33a and 33b. It is possible to maintain the ink amount in the sub-tank 7 at a constant amount at all times and make the head difference between the ink upper surface in the sub-tank 7 and the nozzle forming surface of the recording head 6 constant. In addition, for example, by using a sub-tank that can store only the amount of ink that can be recorded on A0 size paper,
It is not necessary to provide the ink storage amount detecting means in the sub tank 7 as described above, and the manufacturing cost can be reduced.

In addition, an ink outlet port 48 is formed in the sub tank 7 close to the ink supply port 46. A filter member 49 for trapping a foreign substance forming a pentagon (home base shape) is arranged so as to cover the ink outlet port 48. Therefore, the ink stored in the sub tank 7 passes through the filter member 49. And is led to the ink outlet 48. Moreover, since the ink outlet port 48 is formed in the vicinity of the ink supply port 46, the relatively new ink introduced into the sub tank 7 acts so as to be immediately discharged from the outlet port 48.

As shown in FIG. 13, the ink led out from the ink outlet 48 is led out to the groove 50 formed on the back surface of the side wall 41a, and the film-shaped member 51 heat-welded so as to cover the groove. It is configured to reach the valve unit 35 arranged at the lower bottom portion of the sub-tank 7 through the formed ink outlet path. Then, via the valve unit 35, the ink lead-out path (also denoted by the same reference numeral) formed by the film-shaped member 51 that is led out to the groove portion 52 similarly formed on the back surface of the side wall 41a and heat-sealed so as to cover the groove portion 52. (Indicated by 52), the ink is supplied to the connection port 53 of the ink supply tube 36 connected to the recording head 6.

On the other hand, in the upper half part of the sub tank 7, FIG.
As shown in FIG. 12 and FIG. 12, the conductive groove 61 that conducts to the ink storage space 43 is formed in an inclined state, and the upper end portion of this conductive groove 61, that is, the high portion of the sub tank 7 in the direction of gravity, of the sub tank 7. An atmosphere communication port 62 is formed on the back surface of the side wall 41a. This atmosphere communication port 62 is
As shown in FIG. 13, it is arranged on the back surface of the sub tank 7,
It is closed by a water-repellent film 63 formed in a substantially rectangular shape that allows the passage of air and blocks the passage of ink.

The water-repellent film 63 is formed on the side wall 4 of the sub tank 7.
It is arranged so as to be housed in a recess formed in the back surface of the la 1a, and is held by a film member 64 heat-welded so as to cover the upper back surface of the side wall 41a. A meandering groove 65 is formed on the back surface of the side wall 41a via the water-repellent film 63, and an end portion of the meandering groove 65 communicates with a bottomed hole 66 formed in the side wall 41a of the sub tank 7. There is. The meandering groove 65 and the bottomed hole 66 are covered in an airtight state by the film member 64. Therefore, the meandering groove 65 and the film member 64 cause an air flow resistance path (the reference numeral 65 is the same as the meandering groove). Are formed.

Then, the film-like member 64 covering the bottomed hole 66 is broken with a sharp tool or the like to open the atmosphere opening port 6
2 is communicated with the atmosphere via an air flow resistance path 65 formed in a meandering shape. As described above, since the atmosphere communication port 62 formed in the sub tank 7 is configured to be covered with the water repellent film 63, the water repellent film 63 is not formed when the entire recording apparatus is accidentally turned upside down. It is possible to avoid the problem that the existence of the ink causes the ink in the sub tank 7 to leak.

Further, the bottomed hole 66 formed at the end of the air circulation resistance path 65 is covered in advance with the film member 64 in an airtight state, so that liquid leakage of the sub tank is completed when the sub tank is completed. (Ink leak) can be checked, and when this check is completed,
By destroying the film-like member 64 that covers the bottomed hole 66, it is possible to provide the original function. A through hole 67 is formed in the sub-tank 7, and each sub-tank 7 is supported in parallel by a single support shaft (not shown) that supports the sub-tank 7 by penetrating the through-hole 67. The sub tank unit can be configured.

FIG. 14 is an exploded perspective view showing a detailed structure of the float member 31. As shown in FIG. 14, the float member 31 includes a side wall 71a and a peripheral side wall 71b continuous with the side wall 71a.
And a box-shaped member 71 integrally formed with the box-shaped member 7
It is configured by a closing member 72 that closes the first opening to form a hollow inside. As the closing member 72,
A film-like member made of transparent resin is used, and the film-like closing member 72 is attached to the opening peripheral edge of the box-like member 71 in a close contact state, for example, by heat welding means, whereby the inside is in a hollow state. Is formed in.

The float member 31 formed in this way
Is integrally formed on the movable free end side of a support arm member 45 that is movable around a support shaft 44 formed in the sub tank 7 as a rotation center. A support ring 73 is integrally formed at the base end portion of the support arm member 45, and the support ring 73 is rotatably mounted on the support shaft 44 so that the support shaft 44 serves as a rotation center. It is configured to be supported. A permanent magnet 32 is attached to the free end side of the support arm member 45, and the permanent magnet 32 is covered with a film member 74 attached to the surface thereof and stored in the sub tank 7. It is designed to avoid the chemical adverse effects of the ink.

Further, positioning pins 75 are formed on a part of the float member 31 and the support arm member 45 at three locations so as to project in the horizontal direction on both outer sides thereof. It is desirable that these positioning pins 75 project from both side surfaces of the float member 31 by 1 mm or more, so that a distance of at least 1 mm or more is maintained between the float member and the support arm member and the inner wall of the sub tank 7. To work. As a result, it is possible to solve the problem that the surface tension of the ink acts between the float member 31 and the inner wall of the sub tank 7 to hinder the movement of the float member 31.

FIG. 15 is an enlarged sectional view showing the valve unit 35 as the flow path opening / closing means arranged in the sub tank 7. Note that the structure shown in this figure is based on the valve unit 1.
The same applies to 5V and 37V. As shown in FIG. 15, the valve unit 35 is disposed between the sub tank 7 as an ink storage unit and the recording head 6 and has a function of controlling opening / closing of the ink supply path to the recording head 6.

When the valve unit 35 is closed, a negative pressure is applied from the suction pump 37 to the cap unit 15 in which the nozzle forming surface of the recording head 6 is sealed, and the negative pressure is sufficiently accumulated. In this state, the valve unit 35 is controlled to open. With this control, a rapid flow of ink is instantaneously created in the ink flow path from the sub-tank 7 to the nozzle opening 6a of the recording head 6, and the bubbles remaining in the ink flow path are effectively discharged.

For the valve unit 35, a diaphragm valve 35a made of a flexible material such as a rubber material is used. The diaphragm valve 35a is mounted such that its peripheral portion is sandwiched between a box-shaped member 41 that constitutes the sub-tank 7 and a cylinder member 35c that is mounted to the box-shaped member 41 with screws 35b. There is. Then, one end of the rod member 35d as an actuating member is attached to the lower surface side of the diaphragm valve 35a in the direction of gravity, and the diaphragm valve 35a receives the driving force in the axial direction of the rod member 35d, and has a substantially central portion. Is configured to be deformed in a direction orthogonal to the surface direction.

The rod member 35d is a cylinder member 35c.
A coil-shaped spring that is configured to be able to move in the inside in the vertical direction and that is arranged between a disc-shaped body 35e formed on the rod member 35d and a spring receiving member 35f arranged on the inner bottom of the cylinder member 35c. Due to the action of 35g, the central portion of the diaphragm valve 35a is urged so as to project upward as shown by the chain line. Diaphragm valve 35a
The upper side in the gravity direction of the recording head 6 from the sub tank 7
The opening / closing control chamber 35h of the ink supply path toward the side is formed. An outlet opening 35i in the opening / closing control chamber 35h extending from the opening / closing control chamber 35h toward the recording head 6 is formed immediately above the center of the diaphragm valve 35a.

Further, around the outlet opening 35i in the opening / closing control chamber 35h, a ring-shaped contact surface 35n with which a ring-shaped protrusion formed on the diaphragm valve 35a, which will be described later, contacts is formed.
Are formed. Then, an inclined surface 35j is formed continuously around the annular contact surface 35n, the diameter of which decreases in the antigravity direction. In this example, the inclination angle of the inclined surface 35j is about 45 degrees with respect to the gravity direction, and the inclination angle of the inclined surface 35j is 45 degrees.
It is desirable that the angle is within ± 15 degrees with respect to the degree.

On the other hand, from the sub tank 7 to the opening / closing control chamber 35h
The inlet opening portion 35k reaching to is formed at a position avoiding just above the central portion of the diaphragm valve, that is, at a part of the inclined surface 35j. Further, an annular convex portion 35m is formed at the substantially central portion of the diaphragm valve 35a facing the opening / closing control chamber 35h.
Are integrally formed, and the upward deformation of the diaphragm valve 35a causes the annular convex portion 35m to become the outlet opening 35.
abutting on an annular contact surface 35n formed around i,
It is configured so that the outlet opening 35i can be closed.

In the above structure, the central portion of the diaphragm valve 35a is normally deformed so as to project upward under the action of the spring member 35g, and as shown by the chain line in FIG. 15, the central portion of the diaphragm valve 35a. The annular convex portion 35m formed in the portion abuts on the annular contact surface 35n formed in the opening / closing control chamber 35h, and acts to close the outlet opening 35i.

When printing is performed by the recording head 6, the rod member 35d is pulled downward by the driving force of an actuator (not shown), whereby the normally closed diaphragm valve 35a is controlled to open and close. The outlet opening 35i formed in the chamber 35h is opened to open the valve. Further, even when the cleaning operation of the recording head 6 is performed, the diaphragm valve 35a is valve-opened in a state where the cap unit 15 seals the nozzle forming surface of the recording head 6 and negative pressure is accumulated.

The valve unit 3 constructed as described above
5 is a diaphragm valve 35a by a rod member 35d.
It is possible to open the valve by pulling the central part of the valve slightly downward, and it is possible to close the diaphragm valve 35a by releasing the pulling of the rod member 35d. Therefore, the actuating force of the actuator required for the opening / closing operation of the valve unit 35 is very small.

The valve unit 35 is closed when the nozzle forming surface of the recording head 6 is sealed by the cap unit 15 and receives the negative pressure from the suction pump 37, and the diaphragm valve 35a to the recording head 6 are closed. The valve is opened in a state where the ink flow path leading to is accumulated in negative pressure. By following such an operation sequence, it is possible to instantly generate a fast flow of ink in the ink flow path immediately after the valve unit 35 is opened, and to increase the viscosity of the ink in the ink flow path.
In particular, bubbles remaining in the opening / closing control chamber 35h can be discharged to the cap unit 15 side.

In this case, in the valve unit 35, the opening / closing control chamber 3 is provided above the diaphragm valve 35a in the gravity direction.
5h is formed, an outlet opening 35i extending from the opening / closing control chamber 35h to the recording head 6 is formed immediately above the substantially central portion of the diaphragm valve 35a, and a diameter is formed around the outlet opening 35i in the antigravity direction. Since the small inclined surface 35j is formed, the bubbles remaining in the opening / closing control chamber 35h can be guided to the vicinity of the outlet opening 35i by the floating action. This makes it possible to further enhance the effect of discharging the residual air.

Further, an annular convex portion 35m formed in substantially the center of the diaphragm valve facing the opening / closing control chamber 35h.
Is an annular contact surface 35n formed in the opening / closing control chamber 35h.
Since it acts so as to close the outlet opening 35i toward the recording head 6 in close contact with, the annular convex portion 35m constitutes a flexible sealing surface, and the rod member 35d is reliably moved in accordance with the linear movement operation. On-off valve operation can be obtained. The annular contact surface 35n is a flat surface,
It is desirable that the width of the surface is formed to be the minimum width that allows the annular convex portion 35m to be in close contact with the diaphragm valve 35a when the diaphragm valve 35a is closed. It is possible to enhance the excretion of the air motility induced by.

According to this structure, when a negative pressure is applied while the recording head 6 is in the capping state, the diaphragm valve 35a receives the negative pressure and the sealing property in the closed state is further improved, so that the valve is closed reliably. It will keep functioning. Further, by adopting the diaphragm valve, the volume change on the recording head 6 side due to the opening / closing valve operation can be minimized, and there is a problem that the meniscus of the ink formed in the nozzle opening 6a of the recording head 6 is destroyed. It can be avoided.

FIG. 16 is a view showing another example of the valve unit 35, and is a sectional view in which the opening / closing control chamber 35h shown in FIG. 15 is further enlarged. The structure shown in this figure is the same for the valve units 15V and 37V. As shown in FIG. 16, from the opening / closing control chamber 35h to the recording head 6
Exit opening 35i in the opening / closing control chamber 35h toward the
Is formed immediately above the central portion of the diaphragm valve 35a, and the inlet opening 35k in the opening / closing control chamber 35h from the ink storage portion to the opening / closing control chamber 35h is replaced by the outlet opening 35k.
It is formed at a lower position in the gravity direction with respect to i.

In this way, by forming the inlet opening 35k at a lower position in the gravity direction with respect to the outlet opening 35i, the opening 35k from the inlet opening 35k to the upper outlet opening 35i in the opening / closing control chamber 35h. It is possible to generate an orderly flow of ink, and to accelerate the discharging action of bubbles remaining in the opening / closing control chamber 35h.

The distance h between the annular contact surface 35n formed in the opening / closing control chamber 35h and the convex portion 35m of the diaphragm valve is 1.0 m when the diaphragm valve is open.
It is desirable that the thickness is set to m to 1.3 mm. If this distance h is less than 1.0 mm, a phenomenon occurs in which bubbles remaining in the opening / closing control chamber 35h are caught between the convex portion 35m of the diaphragm valve and the annular contact surface 35n, and the opening / closing control chamber 35h. The degree to which the discharge property of bubbles from 35h is obstructed becomes large. Also, the distance is 1.3 mm
If it exceeds, the change in the internal volume of the opening / closing control chamber 35h becomes large during the opening / closing operation of the diaphragm valve 35a, which causes an unnecessary pressure fluctuation particularly to the recording head 6, which is not preferable.

On the other hand, the flow passage area of the ink outlet path 52 extending from the outlet opening portion 35i in the opening / closing control chamber 35h to the recording head 6 is equal to the outlet opening portion 35 in the opening / closing control chamber 35h.
It is configured such that it is small in the immediate vicinity of i and increases with increasing distance from the opening / closing control chamber 35h. With this configuration, it is possible to increase the flow velocity of the ink in the outlet opening portion 35i of the opening / closing control chamber 35h and improve the discharge property of bubbles in the opening / closing control chamber 35h.

17 and 18 are sectional views showing a part of the structure of the main tank 9 and a part of the structure of the cartridge holder 8. In FIG. 17, the main tank 9 is loaded into the cartridge holder 8. FIG. 18 shows the state immediately before (or the state where the cartridge holder 8 is pulled out).
The states in which the main tank 9 is loaded in the cartridge holder 8 are shown.

As shown in FIGS. 17 and 18, the ink outlet plug 101 of the ink pack 24 in which ink is sealed at the end of the case 100 which constitutes the outer member of the main tank 9.
Is attached. In this ink outlet plug 101,
A valve member 102 is provided which is brought into contact with a connection plug on the side of the cartridge holder 8 and is retracted in the axial direction to open the valve. The valve member 102 is attached by a spring member 103 so as to advance in the axial direction. It is energized.

The valve member 102, which is urged by the spring member 103 so as to advance in the axial direction, is pressed against an annular packing member 104 having a tributary hole formed in the central portion thereof, and as a result, FIG. The ink outlet plug 101 is closed as shown in FIG. Further, the case 100 is formed with a pressurized air introduction port. This pressurized air introduction port forms a cylindrical body 1 that forms an air passage communicating with the pressure chamber 25.
The tubular body 105 is integrally formed so as to project toward the front end side of the main tank.

On the other hand, on the cartridge holder 8 side, an ink receiving connection plug 111 is formed so as to project in the center thereof. When the main tank 9 is loaded, the ink receiving connection plug 111 is brought into contact with the ink outlet plug 101 on the main tank 9 side to open the valve, and when the cartridge holder 8 is unloaded, the valve closed state is set. Is configured to be retained.

That is, the ink receiving connection plug 111 has a hollow needle 113 having an ink introduction hole 112,
A position that is slidably arranged so as to surround the outer circumference of the hollow needle 113 and closes the ink introduction hole 112 formed in the hollow needle 113 under the bias of the spring member 114 when the cartridge holder 8 is not loaded. An annular sliding member 115 that moves to the right is provided.

Therefore, in the case where the main tank 9 is in the unloaded state as shown in FIG. 13, the annular sliding member 1
15 is moved forward by the bias of the spring member 114, and the hollow needle 1
The ink introduction hole 112 formed in 13 is closed to close the valve. Further, in the case where the main tank 9 is loaded in the cartridge holder 8 as shown in FIG. 14, the ink outlet plug 101 on the main tank 9 side comes into contact with the annular sliding member 115 to retract it. Hollow needle 11
The ink introduction hole 112 formed in No. 3 is exposed, and the valve is opened so that ink can be introduced.

At this time, on the main tank 9 side, the tip of the hollow needle 113 on the cartridge holder 8 side contacts the valve member 102 through the through hole formed in the packing member 104, and the valve member 102 is axially moved. The ink outlet plug 101 on the side of the main tank 9 is also opened to retract it. As a result, ink can be supplied from the main tank 9 to the cartridge holder 8 side as shown by the arrow in FIG.

At the same time, the cylindrical opening 105 forming the pressurized air introduction port on the cartridge 8 side also enters into the annular packing member 122 of the pressurized air supply plug 121 arranged on the cartridge holder 8 side. As a result, the packing member 122 is tightly connected to the outer peripheral surface of the tubular body 105, and pressurized air can be introduced into the pressure chamber 25 on the cartridge 8 side as shown by the arrow in FIG.

With the above configuration, the cartridge holder 8
When the main tank 9 is removed from the tank, the ink outlet plug 101 arranged on the main tank 9 side is closed as shown in FIG. 17, so that the ink is prevented from leaking due to gravity. You can At the same time, since the ink receiving connection plug 111 on the cartridge holder 8 side is also closed, it is possible to prevent the reverse flow of ink from the sub tank 7 side.

FIG. 19 is a perspective view showing a partial structure of the cartridge holder 8. The cartridge holder 8 is provided with a cover member 131 that is opened when the main tank 9 is attached or detached. That is, the cover member 131 is arranged on the front surface of the opening of the cartridge holder 8, and the rotation shaft 131a is supported by the support hole formed on the apparatus main body side (not shown). The front face of the opening of 8 can be opened (state shown by a solid line) or closed (state shown by a chain line).

Inside the cover member 131 in the closed state, a plurality of operation levers 132 are arranged corresponding to each main tank 9 loaded in the cartridge holder 8. A locking hole 132a is formed at the base end of the operating lever 132.
Is formed and is rotatably supported by a support rod (not shown) which is inserted into and supported by the respective locking holes 132a of each operation lever 132.

The operating lever 132 is the cover member 1
In the state where 31 is opened, the main tank 9 can be loaded or unloaded by rotating the cover member 131 in the same direction as the opening direction. That is, when loading the main tank 9 into the cartridge holder 8, the main tank 9 is inserted into the cartridge holder 8 with the operation lever 132 rotated in the same direction as the opening direction of the cover member 131, and the operation lever By raising 132, the pressing portion 132b formed on the operation lever 132 comes into contact with the front end of the main tank 9, and the main tank 9 is loaded on the cartridge holder 8 side by the lever principle.

When the main tank 9 loaded in the cartridge holder 8 side is pulled out, the operating lever 132 is also rotated in the same direction as the opening direction of the cover member 131, although not shown. ,
The main tank 9 is pushed out from the back side through the link rod engaged with a part of the operation lever 132. Therefore, the main tank 9 pushed out in the front direction can be easily pulled out.

The cartridge holder 8 is further provided with an electric switch 133 for detecting the opening of the cover member 131. The switch 133 has a cover member 131.
There is used, for example, a tact switch which is turned on by contacting the back surface of the cover member 131 in the closed state, and turned off in the opened state of the cover member 131.

The tact switch 133 controls the energization to the electromagnetic plunger 91 in the pressure adjusting valve 22 which also serves as the atmosphere release valve.
Is on, that is, when the cover member 131 is closed, the electromagnetic plunger 91 can be energized, and the tact switch 133 is off, that is, the cover member 13.
When 1 is open, it acts so as to cut off the energization to the electromagnetic plunger 91.

Therefore, the ink jet printer 2
When the main tank 9 is to be pulled out from the cartridge holder 8 while the operating power supply to 00 is turned on, the energization to the electromagnetic plunger 91 is cut off based on the opening of the cover member 131 mounted on the cartridge holder 8. To be done. As a result, the pressure adjusting valve 22 that also functions as an atmosphere opening valve is opened, and the pressurized air that is attached to the cartridge holder 8 and applied to the main tank 9 is instantly released. Therefore, since the outer shell member of the main tank 9 which has been expanded to some extent under the action of the pressurized air returns to its original shape, it can be easily pulled out from the cartridge holder 8, and the main tank 9 can be easily operated during the operation. It is also possible to avoid problems such as damage to both the cartridge holder and the cartridge holder.

When pulling out the main tank 9 from the cartridge holder 8, the pressurized air supply plug in which the cylindrical body 105 forming the pressurized air introduction port formed in the main tank 9 is arranged on the cartridge holder 8 side It is considered that the pressure chamber 25 of the main tank 9 is opened to the atmosphere at the moment when it is separated from 121. Therefore, when the main tank 9 is pulled out from the cartridge holder 8,
The pressurization to the main tank 9 is immediately eliminated, and imperfections such as ink ejection due to the action of the residual pressurized air are eliminated.

However, it is preferable to additionally use means for releasing the pressurized air based on the opening of the cover member 131 mounted on the cartridge holder 8. That is,
At the moment when the main tank 9 is about to be separated from the cartridge holder 8, the ink outlet plug 101 on the main tank 9 side is slightly separated from the ink receiving connection plug 111 on the cartridge holder 8 side while the pressurized air is applied. The situation arises. In this situation, the ink outlet plug 10
1 and the ink receiving connection plug 111 are both in the valve open state. Therefore, when the means for releasing the pressurized air in conjunction with the opening of the cover member 131 is not used together, the ink may blow out at this moment.

Further, when the main tank 9 is pulled out from the cartridge holder 8 and the main tank 9 is not constructed so that the pressurized air introduction port formed in the main tank 9 is opened, , Based on the opening of the cover member 131 of the cartridge holder 8,
It goes without saying that it is extremely important to take measures to release the pressurized air. Further, it is desirable that the driving of the air pressure pump is stopped by turning off the tact switch 133 based on the opening of the cover member 131. With this configuration, meaningless idling of the air pressure pump can be prevented.

20 and 21 are partial sectional views in which a main part of the pressure regulating valve 22 which also serves as an atmosphere opening valve is cut away.
20 shows a state of functioning as a pressure regulating valve, and FIG. 21 shows a state of being open to the atmosphere. 20 and 2
As shown in FIG. 1, the on-off valve unit 81 includes an upper case 81a and a lower case 81 each having a space formed therein.
b, the upper case 81a and the lower case 81 are provided.
It is configured so that it can be divided vertically by b.
A diaphragm valve 82 is arranged at the joint between the upper case 81a and the lower case 81b.

The diaphragm valve 82 is formed by molding a rubber material into a disc shape, and the peripheral portion thereof is the upper case 81a.
The air chamber 83 is sandwiched between the lower case 81b and the lower case 81b, and forms an airtight air chamber 83 in the space of the lower case 81b. The lower case 81b is formed with a pair of connecting pipes 84a and 84b communicating with the air chamber 83, and these connecting pipes 84a and 84b are respectively connected to the air pressurizing pump 2.
1 and the pressure detector 23.

Therefore, the pressurized air from the air pressure pump 21 is applied along the arrow shown in FIG. 21, and is further applied to the pressure detector 23 and each main tank 9 via the air chamber 83. Is applied. A ventilation hole 84c is formed in the center of the lower case 81b, and the diaphragm valve 82 is configured to come into contact with the center of the diaphragm valve 82 at the opening end of the ventilation hole 84c to the air chamber 83.

On the other hand, a drive shaft 85 is arranged in the upper case 81a so as to slide in the vertical direction, and the upper surface of the diaphragm valve 82 is supported by the lower end of the drive shaft 85. An annular spring seat 86 is attached to the drive shaft 85, and a coil-shaped spring member 87 is arranged between the spring seat 86 and the upper space of the upper case 81a. The center portion of the diaphragm valve 82 is biased by 87 so as to come into contact with the open end of the vent hole 84c.

An engaging head portion 88 is provided at the upper end of the drive shaft 85, and is supported by a support shaft 89.
The engaging head portion 88 is attached to the upper portion through which a through hole formed in the drive lever 90 that is rotated in a seesaw shape around the center is provided. An operating rod 91a of an electromagnetic plunger 91 as a driving means is engaged with one end of the drive lever 90.

A spring member, that is, one end of an extension spring 93 is attached to the other end of the drive lever 90 via the support shaft 89. The action of the extension spring 93 causes the drive lever 90 to support the support shaft 89. Is urged to rotate counterclockwise in FIG. And the electromagnetic plunger 9
The engaging head portion 88 of the drive shaft 85 in the on-off valve unit 81 is engaged with the intermediate portion between the one end portion of the drive lever 90 that receives the driving force of 1 and the support shaft 89.

When the electromagnetic plunger 91 is energized, as shown in FIG. 20, one end of the drive lever 90 is pulled down against the biasing force of the tension spring 93. Therefore, the engaging head portion 88 attached to the drive shaft 85 of the opening / closing valve unit 81 is in a state of floating from the drive lever 90. As a result, the diaphragm valve 82 is closed by the biasing force of the spring member 87 and the elastic force held by the diaphragm valve 82 to close the vent hole 84c.

When the pressure in the air chamber 83 exceeds a predetermined value, the diaphragm valve 82 is pushed upward in the air chamber 83, whereby the contact of the diaphragm valve 82 with the vent hole 84c is released. Functions as a pressure control valve. As a result, the air pressure pressurized by the air pressure pump 21 releases the pressure that has reached an excessive state due to some trouble, and maintains the air pressure applied to the main tank 9 within a predetermined range.

On the other hand, when the electromagnetic plunger 91 is de-energized, the drive lever 90 is rotated counterclockwise in the figure by the action of the tension spring 93 as shown in FIG. The drive shaft 85 of the unit 81 is pulled up against the biasing force of the bending member 87 in the opening / closing valve unit 81 and the elastic force held by the diaphragm valve 82. Therefore, from the air chamber 83 to the vent hole 8
4c is opened to the atmosphere in which pressurized air is released.

As described above, when the electromagnetic plunger 91 is de-energized, it is opened to the atmosphere. Therefore, when the cover member 131 mounted on the cartridge holder 8 is opened, the electromagnetic plunger 91 is de-energized. By configuring so as to cut off, the air pressure applied to each main tank 9 as the cover member 131 is opened is instantly released. Further, when the operating power supply of the inkjet printer 200 is turned off, the power supply to the electromagnetic plunger 91 is also cut off.
In the rest state, the pressure is automatically released. As a result, when the inkjet printer 200 is not used, the air pressure applied to the main tank 9 is released, and when the inkjet printer 200 is at rest, residual air pressure may cause a problem such as ink leakage from the main tank 9. It can be avoided.

FIG. 22 shows an ink jet printer 20.
FIG. 3 is a block diagram showing the configuration of a control circuit mounted on 0. As shown in FIG. 20, the print control unit 170 generates bitmap data based on the print data supplied from the host computer, and the head drive unit 171 generates a drive signal based on the bitmap data, Ink droplets are ejected from the recording head 6. The head drive unit 171 receives a flushing command signal from the flushing control unit 172 and outputs a drive signal for flushing operation to the recording head 6 in addition to the drive signal based on the print data.

The cleaning control means 173 operates the pump drive means 174 to drive and control the suction pump 37. The cleaning control unit 173 includes a print control unit 170 and a cleaning sequence control unit 175.
Also, a cleaning command signal is supplied from the cleaning command detection means 176. A cleaning command switch 177 is connected to the cleaning command detecting means 176, and a user pushes the cleaning command switch 177 to operate the cleaning command detecting means 176 to perform a manual cleaning operation. It is supposed to be done.

Cleaning sequence control means 175
Receives a command signal from the host computer and sends a control signal to the cleaning control means 173, the valve unit driving means 178 and the carriage driving means 179. The valve unit driving means 178 drives an actuator (not shown) that pulls the rod member 35d arranged in the valve unit 35 downward to open the valve unit 35. Further, the carriage driving unit 179 drives the carriage motor 2 to move the carriage 1 to the home position side, and causes the cap unit 15 to cap the nozzle forming surface of the recording head 6.

The sub-tank position adjusting means 182 reads the head ID determined at the time of manufacture from the head ID storing means 180 by the appropriate drive waveform maximum voltage VH of the recording head 6, and according to the head ID, the sub-tank adjustment value storage table 181 reads the sub-tank. The water head adjustment value H of 7 is selected, and the actuator 17 is operated based on the water head adjustment value H to adjust the position of the sub tank 7.

FIG. 23 shows the valve units 35, 15V,
25 is a flowchart showing an example of a cleaning operation performed by using the 37V function, and the cleaning operation sequence will be described below with reference to FIG. First, when the cleaning operation is started, among the valve units 15V and 37V which are closed in advance, the valve unit 15 corresponding to the recording head 6 to be cleaned is first.
V is selected and the valve is opened.

This is because the cleaning sequence control means 175 receiving a command from the host computer controls the valve unit driving means 178 so that the rod member in the valve unit 15V receives the driving force of the actuator and is pulled downward. Is executed (step S11). In addition, the valve unit 15V, 3
Since 7V is closed in advance, the depressurizing time during the cleaning operation can be shortened.

Subsequently, the carriage 1 moves to the home position side (step S12), and the nozzle forming surface of the recording head 6 is capped by the cap unit 15 (step S13). And the valve unit 3
7V is selected so as to have a predetermined suction force, and the valve is opened. This is executed by the cleaning sequence control means 175 receiving a command from the host computer controlling the valve unit driving means 178 so that the rod member in the valve unit 37V receives the driving force of the actuator and is pulled downward. (Step S14).

Following this, the selected suction pump 37
Is driven. This is executed by sending a control signal from the cleaning sequence control means 175 to the cleaning control means 173 and sending a command signal from the cleaning control means 173 to the pump drive means 174 (step S15). Then, the elapse of the predetermined time is awaited (step S16).

Then, the valve unit 37V is further selected so as to have a predetermined suction force and is opened, and the selected suction pump 37 is driven (step S1).
7, 18). Then, the elapse of the predetermined time is awaited (step S19). As a result, the bubbles present in the ink flow path along with the thickened ink, especially the bubbles remaining in the opening / closing control chamber 35h, are discharged to the cap unit 15 side, and the ink discharged into the cap unit 15 is sucked by the suction pump 37.
And is discarded in the waste liquid tank 38.

Next, the driving of the suction pump 37 is stopped (step S20), and the capping of the recording head 6 by the cap unit 15 is released (step S2).
1). Then, the carriage 1 moves to the print area side (step S22), the nozzle forming surface of the recording head 6 is wiped by the wiper unit 16, and the paper dust and the like adhering to the nozzle forming surface of the recording head 6 is removed. .

This is executed by the cleaning sequence control means 175 which has received a command from the host computer and sends a control signal to the carriage drive means 179 (step S23). Further, the carriage 1 moves to a position where the recording head 6 and the cap member 15a face each other (step S24), the recording head 6 is flushed, and the cleaning process is ended.

On the other hand, in the case of performing choke cleaning, when it is determined in step S16 that the predetermined time has elapsed, the process branches to A, and the valve unit 35 subject to choke cleaning is selected and closed.
This is executed by the cleaning sequence control means 75 receiving a command from the host computer controlling the valve unit driving means 178 so that the valve unit 35 receives the biasing force of the spring member 35g housed in the unit. (Step S25).

Then, the selected suction pump 37 is driven to wait for a predetermined time (step S26).
As a result, negative pressure is accumulated in the ink supply path from the sub tank 7 to the recording head 6. Then, the valve unit 35 is controlled to open. This is because the cleaning sequence control means 175 controls the valve unit driving means 178 and the rod member 35d in the valve unit 35.
Is executed by receiving the driving force of the actuator and being pulled downward (step S27). Due to the opening of the valve unit 35, a rapid flow of ink is instantaneously generated in the ink supply path from the sub tank 7 to the recording head 6, and the bubbles present in the ink flow path along with the thickened ink, in particular, opening and closing. The bubbles remaining in the control chamber 35h are discharged to the cap unit 15 side, and the choke cleaning process is completed.

In the above-described embodiment, the printer has been described as an example, but the present invention is not limited to this, and is applicable to a recording apparatus having a recording medium conveyance guide unit, such as a facsimile apparatus or a copying apparatus. is there.

[0147]

As described above, according to the ink jet recording apparatus and the adjusting method thereof according to the present invention, since a large number of independent head units are arranged on the carriage, the characteristics can be adjusted to some extent. It becomes possible to selectively install a head unit, or to replace a head unit having deteriorated characteristics with a head unit having predetermined characteristics, and improve throughput with respect to a large-sized recording medium. The recording accuracy can be increased and maintained. further,
Since it is possible to adjust the water head difference between the ink surface in the sub tank and the nozzle formation surface of the recording head, it is not possible to make fine adjustment for each recording head, for example, when considering the common drive waveform of the ink jet recording apparatus. Also, the amount of ink ejected from the nozzles can be made uniform, and the recording accuracy can be further improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a configuration example of an ink jet printer according to an embodiment of an ink jet recording apparatus of the present invention.

2 is a partial cross-sectional side view of the inkjet printer shown in FIG.

FIG. 3 is a top view of a printing unit of the inkjet printer shown in FIG.

FIG. 4 is a plan view showing the vicinity of the carriage of the inkjet printer shown in FIG.

5 is a cross-sectional side view taken along the line AA of FIG.

FIG. 6 is a diagram showing the relationship between the head difference and the ink discharge weight for each recording head.

FIG. 7 is a diagram showing a specific example of the characteristics shown in FIG.

8 is a cross-sectional view showing details of a recording head of the ink jet printer shown in FIG.

9 is a diagram schematically showing an ink supply system installed in the inkjet printer shown in FIG.

10 is a diagram schematically showing a cap unit and a printing stage connected to one end of a suction tube of the ink supply system shown in FIG.

11 is a perspective view showing a state in which a part of the sub-tank of the ink jet printer of FIG. 1 is omitted and viewed from one surface direction.

FIG. 12 is a perspective view of the sub-tank of the ink jet printer of FIG. 1 as viewed from one surface direction.

FIG. 13 is a rear view of the sub-tank of the inkjet printer of FIG. 1 as viewed from the rear surface direction.

14 is an exploded perspective view showing a configuration of a float member housed in a sub tank of the ink jet printer of FIG.

15 is an enlarged cross-sectional view showing a valve unit arranged in a part of a sub tank of the ink jet printer of FIG.

16 is an enlarged cross-sectional view of an opening / closing control chamber portion showing another valve unit of the ink jet printer of FIG.

17 is a cross-sectional view showing a part of a configuration of a main tank and a cartridge holder of the ink jet printer of FIG.

FIG. 18 is a cross-sectional view showing a state where the main tank of the ink jet printer of FIG. 1 is attached to the cartridge holder.

19 is a perspective view showing a part of the configuration of the cartridge holder of the ink jet printer of FIG.

20 is a partial cross-sectional view showing a state in which the opening / closing valve unit of the inkjet printer of FIG. 1 functions as a pressure adjusting valve.

FIG. 21 is a partial cross-sectional view showing a state where the on-off valve unit of the inkjet printer of FIG. 1 is opened to the atmosphere.

22 is a block diagram showing a configuration of a control circuit installed in the inkjet printer of FIG. 1. FIG.

23 is a flowchart showing a control routine of a cleaning operation performed by the control circuit shown in FIG.

[Explanation of symbols]

1 Carriage 6 Recording Head 7 (7a, 7b, 7c, 7d, 7e, 7f) Sub Tank 8 Cartridge Holder 9 (9a, 9b, 9c, 9d, 9e, 9f) Main Tank 10 Head Unit 11 Ink Supply Tube 12 Ink Supply Tube 15 Cap unit 15V, 35V, 37V, 224V Valve unit 16 Wiper unit 17 Actuator 21 Air pressure pump 22 Pressure adjusting valve 23 Pressure detector 24 Ink pack 25 Pressure chamber 26 Ink supply valve 31 Float member 32 Permanent magnet 33 (33a, 33a, 33b) Hall element 37 Suction pump 37a Suction tube 38 Waste liquid tank 170 Printing control means 171 Head drive means 172 Flushing control means 173 Cleaning control means 174 Pump drive means 175 Cleaning sequence Control means 176 Cleaning command detection means 177 Cleaning command switch 178 Valve unit drive means 179 Carriage drive means 180 Head ID storage means 181 Sub tank adjustment value storage table 182 Sub tank position adjustment means 200 Inkjet printer 210 Paper feed section 220 Printing section 224 Printing stage 224a Small hole 230 Paper output section 240 Leg section 250 Printer body

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B41J 2/185 F term (reference) 2C056 EA01 EB21 EB51 EC20 EC32 EC57 FA04 FA10 HA37 HA60 JA13 JB04 JC20 KB04 KB37 KC14 KC27 2C057 AF22 AG74 AG76 AG80 AL17 AM31 AM40 AN01 AP82

Claims (22)

[Claims] 1. A main tank, which is mounted on a carriage and reciprocates in the width direction of a recording medium, ejects ink droplets onto the recording medium, and is mounted on the carriage together with the recording head in a positionally adjustable manner. An ink jet recording apparatus, wherein a plurality of head units each having a sub-tank for supplying the ink to the recording head while being replenished with ink are provided. 2. The ink jet recording apparatus according to claim 1, wherein a position of the sub tank is adjusted during recording on the recording medium by the recording head. 3. The ink jet recording apparatus according to claim 1, wherein a position of the sub tank is finely adjusted during an assembly step with the carriage. 4. The ink jet recording apparatus according to claim 3, wherein the fine adjustment of the position of the sub-tank is performed according to the drive waveform proper voltage displayed for each recording head. 5. Storage means for storing the drive waveform proper voltage for each recording head, and adjustment means for finely adjusting the position of the sub-tank by reading the drive waveform proper voltage for each print head from the storage means. The inkjet recording apparatus according to claim 4, further comprising: 6. A table for storing an adjustment value of the position of the sub-tank corresponding to the drive waveform appropriate voltage for each recording head, wherein the adjusting means is the drive for each recording head read from the storage means. The inkjet recording apparatus according to claim 5, wherein fine adjustment is performed based on an adjustment value of the position of the sub-tank selected from the table according to the waveform proper voltage. 7. The fine adjustment of the position of the sub-tank is performed in the direction of lowering the water head with the recording head having the high drive waveform appropriate voltage as a reference.
6. The inkjet recording device according to any one of 6. 8. The ink jet type according to claim 1, wherein each head unit includes the recording heads and the sub tanks for all colors used for color printing. Recording device. 9. The ink jet recording apparatus according to claim 1, wherein a common drive signal is supplied to each recording unit. 10. The ink jet recording apparatus according to claim 1, wherein a plurality of the main tanks are provided at different heights. 11. A cap unit for sealing the nozzle forming surface of each recording head and for sucking and discharging the ink from the recording head is provided for each recording head. The inkjet recording device according to any one of 1 to 10. 12. A first flow path opening / closing means for opening / closing controlling an ink flow path around each of the recording heads is provided for each of the ink flow paths. The ink jet recording apparatus according to the item 1. 13. The ink jet recording apparatus according to claim 12, wherein the first flow path opening / closing means is disposed on the cap unit side. 14. A negative pressure generating means for applying a negative pressure to the ink flow path is provided.
3. The inkjet recording device according to any one of 3 above. 15. A plurality of the negative pressure generating means are provided, and a second flow path opening / closing means is provided for each of the ink flow paths on the side of the negative pressure generating means. 14. The ink jet recording apparatus according to 14. 16. A wiper unit is provided which is movable in the arrangement direction of the recording heads and wipes a nozzle forming surface of the recording heads arranged in a movable region. 16. The inkjet recording device according to any one of 1 to 15. 17. A recording head which is mounted on a carriage and reciprocates in the width direction of a recording medium to eject ink droplets onto the recording medium, and a recording head which is mounted on the carriage together with the recording head so as to be position-adjustable. A method for adjusting an ink jet recording apparatus in which a plurality of head units each having a sub tank for supplying the ink to the recording head are provided while receiving the replenishment of ink from the recording head, A method for adjusting an inkjet recording apparatus, wherein a position is adjusted during recording on a recording medium. 18. The method of adjusting an ink jet recording apparatus according to claim 17, wherein the sub-tank is finely adjusted in a position during the assembling to the carriage. 19. The adjustment method for an ink jet recording apparatus according to claim 18, wherein the fine adjustment of the position of the sub-tank is performed according to the drive waveform appropriate voltage displayed for each of the recording heads. 20. Storage means for storing the appropriate drive waveform voltage for each recording head, and adjustment means for finely adjusting the position of the sub-tank by reading the appropriate drive waveform voltage for each recording head from the storage means. And a table that stores an adjustment value of the position of the sub-tank corresponding to the drive waveform appropriate voltage for each recording head, wherein the adjusting unit is the drive waveform appropriate for each recording head read from the storage unit. 20. The adjustment method for an inkjet recording apparatus according to claim 19, wherein fine adjustment is performed based on an adjustment value of the position of the sub tank selected from the table according to the voltage. 21. The fine adjustment of the position of the sub-tank is performed in a direction of lowering a water head with the recording head having a high drive waveform appropriate voltage as a reference.
21. A method for adjusting an ink jet recording apparatus according to 9 or 20. 22. A computer-executable program, comprising the adjustment method for an ink jet recording apparatus according to claim 17.