JP3387691B2 - Ink jet apparatus and method of operating the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium including paper, plastic sheet, cloth, articles, etc. (hereinafter, typically referred to as "paper"), ink, functional liquid, etc. Characters, symbols, images, etc. (hereinafter, typically referred to as “image”) are recorded and printed (hereinafter, typically referred to as “recorded”) by ejecting ink. The present invention relates to an inkjet device in which an inkjet head to be performed and an inkjet pen including an ink storage unit for storing ink supplied to the inkjet head are mounted. The present invention also relates to a method of operating an inkjet device.

The ink jet pen referred to in the present invention includes both a cartridge form in which an ink jet head and an ink reservoir are integrated, and a form in which they are detachably combined as separate bodies. The inkjet pen is detachable from a mounting means such as a carriage on the apparatus body side. In addition, the inkjet device according to the present invention is provided integrally or separately as an output terminal of an information processing device such as a word processor or a computer, and also has a copying device combined with an information reading device and an information transmitting / receiving function. It means a device including various forms such as a facsimile machine and a machine for printing a cloth.

[0003]

2. Description of the Related Art In an ink jet recording apparatus, water or other volatile components of ink in a nozzle (hereinafter also referred to as "ejection port") evaporate when the apparatus is not used for a long time. And increase the viscosity of the ink,
In some cases, it may be difficult for the ink to be ejected well due to bubbles mixed in the nozzles or the ink path. In order to recover such a state to the original good ink discharge state, the ink jet recording apparatus is often provided with some kind of recovery means. As one of such recovery means, there is a suction mechanism for sucking ink from the nozzle and supplying new ink from the ink tank side to the head when the cap covers the nozzle. Typical elements that constitute such a suction mechanism include a cylinder pump that generates a pressure change by utilizing the relative movement of a cylinder and a piston, and a tube pump that generates a pressure change by squeezing a tube. You can

[0004]

In such an ink jet recording apparatus, the inside of the suction mechanism, that is, the cap, the pump, the ink suction path from the cap to the pump,
Alternatively, there is a possibility that the ink may be dried inside the waste ink flow path or the like from the pump to the waste ink storage portion, and the ink passage may be blocked. For example, if the ink hardens inside the pump, the pump may be stuck. Alternatively, when the ink is solidified in the waste ink flow path and the ink that should originally go to the waste ink storage portion stops flowing, the ink flows back to the head side to deteriorate the ejection characteristics and adversely affect the recording quality,
There is a fear that the ink may overflow from the unexpected place into the device and stain the inside of the device or may adversely affect the electric circuit in the device.

Further, such technical problems also exist on the ink jet head side. For example, as a typical example of the above-mentioned inkjet pen, there may be mentioned a form in which an inkjet head and an ink storage portion for storing ink supplied to this head are integrally joined / separable. The inkjet head is
An ejection port for ejecting ink is provided, and it has an electrothermal converter that generates, for example, thermal energy as energy used for ejecting ink from the ejection port. In many cases, the ink storage portion contains a porous absorber for storing ink. A filter for trapping foreign matters such as dust in the ink is generally provided in the ink supply path for connecting the inkjet head and the ink reservoir.

When such an ink-jet pen is used, if the ink reservoir is not attached to the ink-jet head for a long time, the ink component evaporates from the filter portion of the ink supply path, the ejection port, etc., and the ink is solidified. Ink sometimes adhered to the wall surface of the. Once such ink sticking occurs, there is a problem in that even if the ink storage section is attached to the inkjet head again, the stuck ink may hinder the ink supply, resulting in defective ink ejection. It was

The above-mentioned technical problems become remarkable when using a water-resistant ink which becomes water-insoluble after drying. A water-resistant ink that becomes water-insoluble after drying can meet the recent technical demand for improving the water resistance of a recorded image, but on the other hand, it has created a new technical problem that it easily sticks inside the apparatus. . That is, such a water-resistant ink is a technical problem that it is easily fixed inside the recovery mechanism or inside the ink passage of the inkjet head.

[0008]

One of the objects of the present invention is to solve the above-mentioned technical problems, and to prevent ink sticking in the ink path, or even if ink sticking occurs immediately, so that a stable recording state can be achieved. An object of the present invention is to provide an inkjet device that can be maintained for a long period of time and a method of operating the inkjet device.

Another object of the present invention is to provide an ink jet apparatus capable of maintaining a stable recording state for a long period of time, since ink can be fixed inside the recovery mechanism or can be removed immediately even if it occurs. It is to provide the operation method.

It is still another object of the present invention that ink sticking does not occur or occurs inside a recovery mechanism for recovering an ink jet head using a water resistant ink in which at least one ink becomes water-insoluble after drying. It is an object of the present invention to provide an inkjet device that can be immediately removed and a method of operating the same.

It is still another object of the present invention that ink sticking does not occur or occurs inside a recovery mechanism for recovering an ink jet head using a water resistant ink in which at least one color of ink becomes water insoluble after drying. It is an object of the present invention to provide a color inkjet device that can be immediately removed, and that is unlikely to cause color mixing, and a method of operating the same.

Still another object of the present invention is to provide ink in an ink passage of an ink jet head even when the ink reservoir is not attached for a long time to an ink jet head using a water resistant ink which becomes water-insoluble after drying. It is an object of the present invention to provide an inkjet device and an operating method thereof, in which sticking of ink is less likely to occur, and stable ink ejection can be promptly performed after mounting the ink storage portion.

Still another object of the present invention is to contain urea
An ejection port for ejecting a first ink, and the first ink
Ejects a second ink that has different water resistance and does not contain urea
Discharge port surface with multiple discharge ports arranged
For recording with an inkjet head that has
A jet recording device, which presses against the discharge port surface
The plurality of discharge ports arranged on the discharge port surface.
A cap that can be bundled and sealed, and a cap provided inside the cap.
With suction means for sucking through the opened opening.
In the method of operating a jet recording device, the cap
Is brought into pressure contact with the discharge port surface by the suction means.
The first suction from the plurality of discharge ports
A suction step of sucking ink and the second ink;
The first outlet from the plurality of discharge ports with respect to the cap.
A discharging step for discharging a second ink and the second ink;
With the cap communicating with the atmosphere,
By performing more suction, the cap is removed in the discharging step.
And the second ink ejected in the ink
( EN) A method for operating an ink jet recording apparatus , which comprises sequentially performing a discharging step of discharging ink.

Yet another object of the present invention is to contain urea.
An ejection port for ejecting a first ink, and the first ink
Ejects a second ink that has different water resistance and does not contain urea
Discharge port surface with multiple discharge ports arranged
An inkjet head having the
Ink for storing the ink supplied to the head
The discharge port surface is brought into contact with the storage part by pressure contact with the discharge port surface.
A key that can collectively seal the plurality of discharge ports arranged in
And using the inkjet head described above.
A method of operating an inkjet device for recording, comprising:
When the ink reservoir is not installed, the ink jet
The first ink and the second ink in the wet head
And a discharging step for discharging
Discharge of ink from the plurality of discharge ports, or
Ink is ejected from the plurality of ejection ports to the cap.
It is an object of the present invention to provide a method for operating an inkjet device, which is one of ejecting by ejecting .

Yet another object of the present invention is to contain urea.
An ejection port for ejecting a first ink, and the first ink
Ejects a second ink that has different water resistance and does not contain urea
Discharge port surface with multiple discharge ports arranged
For recording with an inkjet head that has
A jet recording device, which presses against the discharge port surface
The plurality of discharge ports arranged on the discharge port surface.
A cap that can be bundled and sealed, and a cap provided inside the cap.
Suction means for performing suction through the opened opening and the cap.
From the plurality of ejection ports to the first ink
An ejecting unit that ejects the second ink, and the cap
Is pressed against the discharge port surface by the suction means.
By performing suction, the first outlet is discharged from the plurality of discharge ports.
Ink and the second ink, and the discharge means
From the plurality of discharge ports to the cap, the first
Of the second ink and the ink of
Suction by the suction means with the inside communicating with the atmosphere
By doing so, the first ink discharged into the cap is discharged.
Control for discharging the ink and the second ink.
It is to provide an ink jet recording apparatus, comprising: the means.

Yet another object of the present invention is to contain urea.
An ejection port for ejecting a first ink, and the first ink
Ejects a second ink that has different water resistance and does not contain urea
Discharge port surface with multiple discharge ports arranged
An inkjet head having the
Ink for storing the ink supplied to the head
An ink jet device to which a storage part is attached,
It is arranged on the discharge port surface by being pressed against the discharge port surface.
A cap that can seal the plurality of discharge ports at once,
Suction through the opening provided in the cap
When the pulling means and the ink reservoir are not attached
Is the first from the plurality of discharge ports by the suction means.
Control to suck ink and the second ink
An inkjet recording apparatus comprising: a control unit . Still another object of the present invention
Is an ejection port for ejecting the first ink containing urea,
Does not contain urea, which has a different water resistance from the first ink
A plurality of ejection ports including ejection ports for ejecting the second ink
An inkjet head having a discharge port surface in which
Stores the ink supplied to the inkjet head
The ink jet that is installed with the ink reservoir for retaining
A discharge device, the discharge port is formed by pressing the discharge port surface against the discharge port.
The multiple outlets arranged on the outlet surface can be sealed at once
Cap and the multiple discharges to the cap
Ejecting the first ink and the second ink from the mouth
If the ejection means and the ink reservoir are not installed
When the discharge means is used,
The first ink and the second ink from a plurality of ejection ports
And a control means for controlling so as to discharge
To provide a characteristic inkjet recording device.
It

[0017]

The present invention is intended to solve the above-mentioned technical problem of ink sticking inside the recovery mechanism, and more particularly, the more remarkable technical problem when using a water-resistant ink that becomes water-insoluble after drying. It was the result of keen research by the researchers. That is, the gist of the present invention is to prevent or remove ink sticking inside a recovery mechanism including a cap by performing preliminary ink ejection to the inside of the cap after performing suction recovery via the cap. After that, the ink remaining in the recovery mechanism is discharged by idle suction, so that the ink itself causing the ink sticking is eliminated from the recovery mechanism. In this case, in an inkjet device that uses both a water-resistant ink that becomes water-insoluble after drying and a normal non-water-resistant ink, even if ink sticking occurs due to the water-resistant ink, the non-water-resistant ink is not discharged by preliminary ejection. Since they are mixed, the effect of the present invention of preventing or removing the sticking of the ink becomes more remarkable.

When water-resistant inks that become water-insoluble after drying and inks of different colors are used as normal non-water-resistant inks, suction is performed through a cap that collectively covers the discharge ports for discharging them. There is a technical problem that different inks mix in the cap and flow back into the ejection port to mix colors. However, according to the present invention, the mixed color ink can be discharged from each discharge port by performing the preliminary discharge after the suction, so that the technical problem of color mixing can be solved.

According to the present invention, the ink in the ink jet head is discharged even if the ink storage part is not attached for a long time to the ink jet head using the water resistant ink which becomes water-insoluble after drying. Ink is not likely to stick in the ink passage of the inkjet head, and stable ink ejection can be performed promptly after mounting the ink reservoir.

In the present invention, "suction" means that when the cap covers the discharge port, the suction means typified by a pump is driven to perform suction from the discharge port via the cap. The "empty suction" referred to in the present invention allows the inside of the cap to communicate with the atmosphere when the cap opens the discharge port or even when the cap covers the discharge port by opening a valve that communicates with the cap. At times, this means that the suction means typified by a pump is driven to perform suction by drawing the atmosphere into the recovery mechanism through the cap. The discharged ink is finally guided to, for example, a waste ink storage section provided in the main body, and is held so as not to leak outside. In the present invention, "preliminary ejection" means ejection of ink irrelevant to recording to an ink receiving means such as a cap. In the present invention, “wiping” means wiping off foreign matter such as ink droplets and dust adhering to the ejection port surface provided with the ejection port of the inkjet head, usually with a wiper blade made of an elastic body.

[0021]

The preferred embodiments of the present invention will be described in detail below.

FIG. 1 is a perspective view showing a main part of an example of an ink jet recording apparatus (IJRA) suitable for applying the present invention.

In FIG. 1, 5001 is an ink tank (IT), and 5012 is an ink jet recording head (IJH) connected thereto. Ink tank 50
01 and the recording head 5012 form an integral replaceable inkjet cartridge (IJC). 501
Reference numeral 4 denotes a carriage (HC) which carries an inkjet cartridge (IJC) and moves, and reference numeral 5003 denotes a guide for guiding the carriage (HC) in the main scanning direction.

Numeral 5000 is a platen roller for scanning the recording member indicated by the symbol P in the sub-scanning direction. 5
Reference numeral 024 is a temperature sensor for measuring the environmental temperature in the device. The carriage 5014 has a recording head 501.
A flexible cable (not shown) for supplying a pulse signal current for driving and a current for head temperature adjustment is connected to the No. 2. The flexible cable is connected to a printed board (not shown) having an electric circuit for controlling the device. A temperature sensor 5024 such as a thermistor is mounted on the printed board to measure the environmental temperature or to estimate the head temperature based on the temperature.

The carriage HC interlocks with the forward and reverse rotations of the drive motor 5013, and the drive force transmission gears 5011 and 5009.
Spiral groove 5 of the lead screw 5005 rotating through
It has a pin (not shown) that engages with 004, and is reciprocated in the direction of arrow a or b as the lead screw 5005 rotates. Reference numeral 5002 denotes a paper pressing plate that holds the recording member P on the platen 500 in the carriage movement direction.
Press against 0. Reference numerals 5007 and 5008 denote photocouplers, which serve as home position detecting means for confirming the presence of the lever 5006 of the carriage HC in this area and switching the rotation direction of the motor 5013. Reference numeral 5016 is a member that supports a cap member 5022 for capping the ejection port surface of the recording head. A suction pump 5015 sucks the inside of the cap, and performs suction recovery of the recording head 5012 through an opening in the cap.

5017 is a cleaning blade, 501
Reference numeral 9 denotes a member that allows the blade 5017 to move in the front-rear direction, and these members are supported by a support plate 5018 on the main body side. Reference numeral 5012 is a lever for starting suction recovery, which moves with the movement of the cam 5020 that engages with the carriage HC, and the driving force from the driving motor is movement-controlled by a known transmission means such as clutch switching. The capping, blade cleaning, and suction recovery are configured such that when the carriage HC comes to the home position side area, desired processing can be performed at the corresponding positions by the action of the lead screw 5005.

FIG. 3 is a sectional view showing a cylinder pump used in the embodiment of the present invention.

In FIG. 3, reference numeral 124 is a cylinder,
It has a cylindrical cylinder portion 124a and a guide portion 124b that guides a piston shaft, which will be described later, and the guide portion 124b is formed with an ink flow path 124c by partially cutting out in the axial direction. Reference numeral 124d denotes a cap lever receiver, which is formed so that a lever seal described later can be fitted therein. Further, 124e is an ink flow path,
It opens at a predetermined position in the cylinder portion 124a. 1
Reference numeral 24f is a rotary lever, which is formed integrally with the cylinder 124 and is given a rotational force by an appropriate means. 124
Reference numeral g denotes a waste ink tube, which is formed integrally with the cylinder 124, and has a tip portion cut into an acute angle to facilitate insertion into a waste ink absorber described later. 1
Reference numeral 24b is an ink flow path formed in the waste ink tube 124g.

Reference numeral 125 denotes a cylinder cap, which is press fitted into the end of the cylinder 124. Reference numeral 125a denotes a lever guide, which is arranged at a position facing the cap lever receiver 124d of the cylinder 124 described above. Reference numeral 126 is a piston seal fitted in the cylinder 124, and its inner diameter is made slightly smaller so that a predetermined pressure contact force with the piston shaft described later can be obtained. Further, the surface may be lubricated to reduce the sliding force of the piston shaft.

Reference numeral 127 is a piston shaft, and the operating shaft 127
a, a piston retainer 127b, a piston receiver 127c, a connecting shaft 127d, and a guide shaft 127e are formed, and further, a groove 127f serving as an ink flow path is formed on the connecting shaft 127.
It is formed along d and the guide shaft 127e. 1
27g is a detent and is formed as a groove on the operating shaft 127a. Further, the bearing portion 1 is provided on the end surface of the operating shaft 127a.
27h is provided. Reference numeral 128 denotes a piston, and the main body forming an inner layer as viewed from the cylinder sliding portion side is formed of an elastic body. The outer diameter thereof is formed to be larger than the inner diameter of the cylinder 124 by a predetermined amount, and when it is inserted into the cylinder 124, it is in a state of being appropriately compressed.

Reference numeral 132 denotes a cap lever that supports the cap member 5022 (see FIG. 1).
It is a member for joining / separating 022 to the ejection port surface of the head and has an ink suction path inside.

4 (A) to 4 (D) are sectional process drawings for explaining a suction recovery process performed using the cylinder pump according to the embodiment of the present invention.

When starting, the cap member 5022
(See FIG. 1) is brought into pressure contact with the discharge port surface by an appropriate mechanism. After the discharge port is sealed and the capping is completed, the suction recovery operation is started.

First, when a member (not shown) pushes the piston pressing roller 129 attached to the piston shaft 127, the piston shaft 127 moves in the H direction as shown in FIGS. 4 (A) and 4 (B). The piston 128 is the piston retainer 12
It is pressed by 7b and moves in the H direction,
Becomes a negative pressure state. Ink flow path 124 of cylinder 124
Since e is closed by the piston 128, the piston 128 can move only by increasing the negative pressure in the pump chamber 142.

When the ink flow path 124e is opened, the ink in the head is sucked through the cap. The sucked ink passes through the ink flow path 132f formed inside the cap lever 132, passes through the communication hole of the lever seal 133,
Further, through the ink flow path 124e of the cylinder 124,
The negative pressure in the pump chamber 142 is relieved by flowing into the pump chamber 142.

Next, by a proper mechanism, the piston shaft 127
Is pulled in the J direction, as shown in FIGS. 4C and 4D, the piston receiver 12 of the piston shaft 127 is moved in the arrow J direction.
Since 7c moves after coming into contact, a gap Δ1 is created between the end surface 128b of the piston 128 (see FIG. 3) and the piston retainer 127. However, the waste ink sucked into the pump chamber 142 due to the movement of the piston shaft 127 and the piston 128 causes the gap Δl, the groove 127f of the piston shaft, and the ink flow path 124c of the cylinder 124.
Then, the waste ink absorber 137 is discharged to the vicinity of the center.

FIG. 2 is a perspective view showing an example of a multicolor integrated type ink jet recording head mounted on the ink jet recording apparatus according to the embodiment of the present invention.

With this head, unlike the case where color recording is performed using four separate recording heads, color recording can be performed with a small apparatus. In order to make full use of the advantage of such a multi-color integrated recording head, that is, the miniaturization can be achieved, even when performing a recovery operation peculiar to the inkjet recording method such as suction, it is different from the case for a single color head. It is preferable that the same recovery operation can be performed. That is, it is desirable that the ink of all the nozzles can be sucked and recovered by a single suction without the nozzles of one color being sucked a plurality of times. However, if ink is collectively sucked from the nozzles of the multi-color integrated recording head, an irregular flow of ink will occur in the cap, and the ink sucked from the nozzle by suction will be transferred to the nozzles of other colors. The problem of intrusion may arise. This causes discoloration (hereinafter also referred to as mixed color) of the writing start portion of each color after recovery and appears on the image.

In order to prevent this color mixture, it is necessary to eject the mixed color ink from the nozzle in the preliminary ejection before printing, but the ink used for this preliminary ejection is not used for printing. It is a waste of ink, so to speak, it is desirable to minimize it. Therefore, it is desirable to minimize this color mixture itself.

In FIG. 2, nozzles for yellow, magenta and cyan inks (200Y, 200M and 200 respectively).
C) has 24 nozzles each, black ink nozzles (200B) has 64 nozzles, and the intervals between the colors are equivalent to 8 nozzles, and they are arranged in a line on the ejection port surface 201 at a nozzle pitch (resolution) of 360 dpi. This inkjet recording head
The ink is heated by utilizing the thermal energy generated by the electrothermal converter (heater) provided along the ink path communicating with the ejection port, thereby causing the ink to foam and eject the ink. About 40p for color ink
1 and black ink, an ink droplet having a volume of about 80 pl can be ejected at about 6 kHz.

The black ink was obtained by mixing the components shown in Table 1 and thoroughly stirring, and then pressure-filtering with a fluoropore filter (Sumitomo Electric Co., Ltd.) having a pore size of 0.45 μm. This ink is a water-containing ink containing urea that becomes water-insoluble after drying. BJ for color ink
A normal non-water resistant ink for a C-600 printer (manufactured by Canon Inc.) was used.

[0042]

[Table 1]

FIG. 5 is a flow chart for explaining the first embodiment of the present invention.

In this embodiment, in the above-described ink jet recording apparatus, as a suction recovery sequence, as shown in the flowchart of FIG. 5, immediately after suction (S2) in the capping state (S1), the cap is opened (S3). Wiping (S4), 2kHz from all nozzles of all colors
After 5000 preliminary discharges (S5) were performed, the idle suction operation (ink discharge operation in the suction mechanism) was performed 5 times (S6).

After that, the test for printing on the recording paper is conducted 20 times.
Repeated 0 times, but no discoloration (color mixture) occurred even at the beginning of writing. After that, the sample was stored in an environment of 60 ° C. for one month, and the same test was conducted again, but in that case as well, there was no abnormality in the operation of the apparatus and no color mixing occurred.

FIG. 6 is a flow chart for explaining the second embodiment of the present invention.

In this Example 2 as well, the ink jet recording apparatus used in Example 1 was used. As a suction recovery sequence, as shown in FIG. 6, immediately after suction (S12) in the capping state (S11), the cap is opened (S1).
3) Wiping (S14) was performed, 3000 preliminary discharges (S15) were performed from all nozzles of all colors at 6 kHz, and then idle suction operation was performed 5 times (S16). That is,
The frequency of the preliminary ejection was increased as compared with that in Example 1, and the recovery sequence was performed with a smaller number of preliminary ejections than in Example 1.

After the recovery sequence was completed, the test for printing on the recording paper was repeated 2000 times, but no discoloration (color mixture) occurred at the beginning of writing. Then 60
The sample was stored in an environment of ° C for 1 month and the same test was conducted again, but in that case, there was no abnormality in the operation of the apparatus and no color mixing occurred.

FIG. 7 is a flow chart for explaining the third embodiment of the present invention.

In this Example 3 as well, the ink jet recording apparatus used in Example 1 was used. As the suction recovery sequence, as shown in FIG. 7, after the suction (S22) in the capping state (S21), the cap is opened halfway (S2).
3: The suction operation (S24) is performed in a state where only a part of the ejection port surface contact portion of the cap is in contact with the ejection port surface of the head) to absorb the ink remaining on the ejection port surface of the head, and then the cap. Open (S25) and wipe (S2
6) is performed, and 3000 preliminary shots (S27) are performed from all nozzles at 6 kHz, and then the idle suction operation is performed four times (S2).
8) done.

After the suction sequence was completed, the test for printing on the recording paper was repeated 200 times, but no discoloration (color mixing) occurred at the beginning of writing. Then 60
The sample was stored in an environment of ° C for 1 month and the same test was conducted again, but in that case, there was no abnormality in the operation of the apparatus and no color mixing occurred.

Which of the second embodiment and the third embodiment can reduce the color mixture, that is, the amount of the preliminary ejection can be determined by the water repellency of the ejection surface of the head, the properties of the ink (surface tension, contact angle, etc.). ), Etc., and it must be finally determined by an experiment including a durability test. However, when a large amount of ink remains on the ejection port surface of the head,
Is preferred.

FIG. 8 is a perspective view showing a main part of another ink jet recording apparatus according to the embodiment of the invention.

An ink jet head (also referred to as an ink jet unit) 11 having ejection openings for ejecting ink arranged in a row is installed on a carriage 13. A recording member P made of a sheet of paper, a plastic thin plate, or the like is nipped by a sheet ejection roller 17 via a conveyance roller (not shown), and is fed in the direction of an arrow when a conveyance motor (not shown) is driven. The carriage 13 is guided and supported by the guide shaft 12 and the encoder (not shown). The carriage 13 reciprocates along the guide shaft 12 by driving the carriage motor 15 via the drive belt 14.

The ink path communicating with the ink ejection port of the ink jet unit is provided with an electric / thermal energy converter which is a heating element for generating thermal energy used for ejecting ink. An image can be formed by driving the heating element based on a recording signal in accordance with the reading timing of an encoder (not shown) and causing the ink to fly and adhere onto the recording material P as droplets.

A recovery unit having a cap portion 16 is arranged at the home position (HP) of the carriage selected outside the recording area. When recording is not performed, the carriage 13 is moved to the home position (HP) and the cap portion 16 seals the ink ejection port surface of the ink jet unit to fix ink due to evaporation of the ink solvent, dust, paper dust, or the like. Prevents clogging due to foreign matter. The cap portion 16 is a preliminary ejection for ejecting ink to the cap portion 16 which is away from the ink ejection port in order to eliminate ejection failure and clogging due to ink thickening, sticking, etc. of the ink ejection port with low recording frequency. It is used for a mode or for operating a pump (not shown) in a capped state to suck ink from the ink ejection port and recover the ejection function of the ink ejection port that has caused ejection failure. Also, by disposing the blade at a position adjacent to the cap portion, it is possible to clean the ink ejection port surface of the inkjet unit.

FIG. 9 is a schematic perspective view showing the ink discharge port array of the ink jet recording head from the recording member side. FIG. 10 is a schematic partial perspective view showing the structure of the ink ejection portion of the inkjet recording head.

This recording head has an ejection port surface 22 provided with a plurality of ejection ports 23 which are open.
Energy generating elements 32 that generate energy used for ejecting ink are respectively disposed in the liquid path portion 31 communicating with the. The arrow y indicates the scanning direction of the carriage 13. Reference numeral 33 in FIG. 10 is a sensor for detecting the temperature of the recording head. In the present embodiment, the thermistors 33 are provided at both ends of the ejection port array. Other sensors such as a diode sensor may be used as the temperature detecting means, and the head temperature may be calculated from the duty of the print dots. 34 is a common ink chamber.

FIG. 11 is a block diagram of an ink jet recording apparatus according to an embodiment of the present invention.

As shown in FIG. 11, the image input section 40 for accessing each main bus line 405.
3, software processing means such as the image signal processing unit 404 and the central control unit CPU 400 corresponding thereto, and the operation unit 40.
6, the recovery system control circuit 407, the inkjet head temperature control circuit 414, and the head drive control circuit 415. CPU 400
Usually has a read only memory (ROM) 401 and a random access memory (RAM) 402, and applies a proper recording condition to input information to drive a recording head 413 to perform recording.

A program for executing a discharge function recovery timing chart which is executed by moving to the home position (HP) described above is stored in the RAM 402, and recovery conditions such as preliminary discharge conditions are recovered as necessary in the recovery system. It is given to the control circuit 407, the recording head 413, the heat retention heater and the like. The recovery system motor 408 drives the above-described recording head and the cleaning blade 409, the cap 410, and the suction pump 411 that face and separate from the recording head. The head drive control circuit 415 executes drive conditions for the electrothermal converters for ink ejection of the recording head, and causes the recording head to perform preliminary ejection and ejection of recording ink.

The print head 413 is provided with a heat-retaining heater on a substrate provided with an electrothermal converter for ejecting ink, and the ink temperature in the print head can be adjusted by heating to a desired set temperature. . Also, the thermistor 41
Similarly, 2 is provided on the substrate for measuring the ink temperature inside the recording head. Note that both the thermistor 412 and the heat retention motor may be provided outside the substrate instead of on the substrate, or in the vicinity of the periphery of the recording head.

FIG. 12 is a schematic cross-sectional view showing an ink jet pen in which the ink tank according to the embodiment of the present invention can be replaced.

This ink-jet pen has an atmosphere communication port 58 for exchanging ink and atmosphere, and an ink tank 57 containing an absorber 59 for holding ink is replaceable with a head along a tank guide 56. Has become.
The ink in the ink tank 57 passes through the filter 54 for trapping dust in the ink and the ink supply path 5
1, the ink is supplied from the common ink chamber 34 to the ink passage 31 provided with the heater and reaches the ejection port 23.

Since the ink tank 57 is replaceable, when the ink tank is not attached to the head, the ink evaporates from the location of the filter 54 and the ink ejection port 23, and the ink is solidified and fixed in the ink passage. May occur. In particular, since the ink used in the examples described below is a water-resistant ink that becomes water-insoluble after drying, the technical problem of ink fixation is remarkable.

FIG. 13 shows the results of investigating the time when the ink tank is not attached to the head and the number of suctions required to restore the function until the ink is ejected from all the ink ejection ports after the ink tank is attached. It is a graph. It can be seen from FIG. 13 that the longer the time the ink tank is not attached, the more the number of suctions required until ink is ejected from all the ink ejection ports tends to increase.

FIG. 14 is a flow chart showing the operation when the ink tank according to the fourth embodiment of the present invention is not attached.

When the replacement operation of the ink tank is set to START and the absence of the ink tank is detected in the presence / absence detection of the ink tank (S71), the ink ejection port of the recording head is capped by the cap (S72) and sucked (S73).
Is performed once or a plurality of times to set the print standby state to END.

FIG. 15 is a schematic sectional view showing an ink jet pen provided with a detection means for detecting whether or not an ink tank is attached.

The ink jet pen shown in FIG.
Ink tank 57 and two electrodes 81 on the tank guide 56
A detection switch mechanism, such as a conductive plate 82, is provided. In FIG. 15, when the ink tank 57 is attached, the conductive plate 82 attached to the ink tank 57.
And the two electrodes 81 attached to the tank guide 56 come into contact with each other and become conductive through the conductive plate 82, and this conductive state is detected as the presence of the tank. When the ink tank is not attached, the conductive plate 82 and the two electrodes 81 do not come into contact with each other, so that conduction does not occur, and this non-conduction state is detected as no tank.

In the suction (S73) of FIG. 14, the suction force is set to a low suction force having a slow negative velocity of 0.5 atm or less and a slow flow rate, so that the liquid passage 31, the common liquid chamber 34, and the supply passage 51 in the print head are provided. The ink can be sucked without running out and can be emptied.

The suction (S73) operation of FIG.
The liquid passage 31 and the common liquid chamber 34 in the recording head can be simply rotated.
Also, the ink in the supply path 51 can be emptied, but it can be emptied more reliably by performing it a plurality of times.

As described above, in the fourth embodiment, by performing the operation shown in FIG. 14, even if the ink tank 57 is not attached to the head for a long time, the liquid passage 3 in the recording head is not used.
1, the ink in the common liquid chamber 34 and the supply path 51 can be removed,
Ink sticking is prevented. Even if sticking occurs, the supply passage 51, the common liquid chamber 34, and the liquid passage 31 are not all covered with the solidified ink, and there is always an ink discharge port communicating with each other. Therefore, when the suction operation is performed after the ink tank is attached, fresh ink is introduced from the ink tank into the supply passage 51, the common liquid chamber 34, and the liquid passage 31, so that the stuck portion is easily redissolved, Recovery is possible in a short time, and stable recording can always be performed.

FIG. 16 is a flow chart showing the operation when the ink tank according to the fifth embodiment of the present invention is not attached.

When the replacement operation of the ink tank is set to START and the absence of the ink tank is detected in the presence / absence detection of the ink tank (S91), the preliminary ejection A (S92) and the preliminary ejection B (S93) are performed once or plural times at the home position. The print standby state is set to END. A switch mechanism as shown in FIG. 15 may be used as a means for detecting the presence or absence of the ink tank.

In the preliminary ejection step of FIG. 16, the conditions are set according to the physical properties of the ink and the shape of the ink ejection port, but the drive frequency of the head is set to be different between the central portion and the end portion of the ink ejection port array. It turns out that the effect is even higher. FIG. 16 shows the central portion as preliminary discharge A (S92) and the end portion as preliminary discharge B (S93). Specifically, it is preferable that the driving frequency of the head is set to a low frequency of 3 KHz or less in the central portion of the ink ejection port array, and is higher than the frequency of the central portion in the end portion, specifically, 3 to 8 KHz. As a result, the ink in the liquid passage in the recording head, the common liquid chamber, and the supply passage can be ejected without being cut off on the way and can be emptied. The ink in the liquid passage in the print head, the common liquid chamber, and the supply passage can be emptied by performing the operations of the preliminary ejection A and the preliminary ejection B of FIG. 16 only once. Can be

As described above, in the fifth embodiment, by performing the operation shown in FIG. 16, even if the ink tank is not attached to the head for a long time, the liquid path in the recording head,
Ink sticking phenomenon in the common liquid chamber and the supply path can be prevented. Moreover, since fresh ink is introduced when the ink tank is attached, even if there is a part where the sticking phenomenon occurs inside, it can be redissolved in a short time. This makes it possible to recover in a short time and always perform stable recording.

FIG. 17 is a flow chart showing the operation when the ink tank according to the sixth embodiment of the present invention is not attached.

When the replacement operation of the ink tank is set to START and the absence of the ink tank is detected in the presence / absence detection of the ink tank (S101), the ink ejection port of the recording head is capped by the cap (S102) and sucked (S1).
03) once or several times, or suction (S103),
The two operations of preliminary ejection (S104) are performed once or a plurality of times, and the print standby state is set to END. The switch mechanism shown in FIG. 15 may be used as a means for detecting the presence or absence of the ink tank.

In the suction (S103) of FIG. 17, suction with a slow negative flow velocity is performed once or a plurality of times by a suction force whose maximum negative pressure is less than 0.5 atm, and then in preliminary discharge,
As in the case of the preliminary ejection shown in the fifth embodiment, the head driving frequency is set higher than the central portion of the ink ejection port array to carry out the preliminary ejection, or the head driving frequency is set to be the same and the head ejection frequency is the same. By making the number of preliminary ejections at both ends larger than that at the center, it is possible to reliably remove the ink that tends to remain on the wall surface of the end of the common liquid chamber after suction, and the liquid passage in the recording head, the common liquid chamber, and the supply passage The ink can be surely emptied without running out. Specifically, when the head drive frequency is set higher than the central portion of the ink ejection port array to perform the preliminary ejection, the central portion of the ink ejection port array has a low frequency of 3 KHz or less and the end portion is the central portion. It is desirable that the frequency is higher than the frequency of 3 to 8 KHz. When the head drive frequency is set to be the same and the number of preliminary ejections in the end portion is larger than that in the central portion of the ink ejection port array, the head drive frequency is set to 0.5 to
In the range of 8 KHz, it is preferable to perform preliminary ejection for 1000 to 5000 dots in the central portion and 5000 to 20000 dots for the end portions. The ink in the liquid passage in the recording head, the common liquid chamber, and the supply passage can be emptied by performing the suction operation (S103) and the preliminary ejection operation (S104) of FIG. 17 only once.
It can be emptied more reliably by repeating the process a plurality of times.

As described above, in the sixth embodiment, by performing the operation shown in FIG. 17, even if the ink tank is not attached to the head for a long time, the liquid passage in the recording head, the common liquid chamber, and the supply It is possible to prevent the ink sticking phenomenon on the road. In addition, since fresh ink is introduced when the ink tank is attached, even if there is a part where a sticking phenomenon occurs inside, it can be redissolved in a short time. This makes it possible to recover in a short time and always perform stable recording.

FIG. 18 is a flow chart showing the operation when the ink tank according to the seventh embodiment of the present invention is not attached.

When the replacement operation of the ink tank is set to START and the absence of the ink tank is detected in the presence / absence detection of the ink tank (S111), the ink ejection port of the recording head is capped by the cap (S112), and the suction A (S
113), the preliminary ejection A (S114) operation is performed, and then the suction B (S115) and preliminary ejection B (S116) operations are alternately performed once or a plurality of times to set the print standby state to END.
And A switch mechanism as shown in FIG. 15 may be used as a means for detecting the presence or absence of the ink tank.

In the suction A (S113) of FIG. 18, suction with a slow flow velocity is performed by the suction force whose maximum negative pressure is less than 0.5 atm, and then the head drive frequency is changed in the preliminary ejection A (S114) of FIG. By performing the preliminary ejection at a frequency of 3 KHz or less, which is lower than that at the time of normal recording, the ink in the liquid passage in the recording head, the common liquid chamber, and the supply passage can be emptied without being cut off. Then, in the suction B (S115) of FIG. 18, suction is performed with a suction force stronger than that of the suction A, specifically, at a negative pressure of 0.5 atm or more, and then in the preliminary discharge B (S116) of FIG. By performing the preliminary ejection at a frequency higher than the drive frequency of the head of the preliminary ejection A, specifically at 3 to 8 KHz, the ink remaining on the liquid passages in the recording head, the common liquid chamber, and the supply passage can be surely removed. Can be removed and emptied. FIG.
The operations of the suction A (S113), the preliminary ejection A (S114), the suction B (S115), and the preliminary ejection B (S116) are performed only once, and the ink in the liquid passage, the common liquid chamber, and the supply passage in the print head is Can be emptied, but it can be emptied more reliably by repeating the process several times.

As described above, in the seventh embodiment, by performing the operation shown in FIG. 18, even if the ink tank is not attached to the head for a long time, the liquid passage in the recording head, the common liquid chamber, and the supply It is possible to prevent the ink sticking phenomenon on the road. Further, since fresh ink is introduced when the ink tank is attached, even if there is a part where the sticking phenomenon occurs inside, it can be redissolved in a short time. This makes it possible to recover in a short time and always perform stable recording.

FIG. 19 is a flow chart showing the operation at the time of replacing the ink tank when the means for detecting the presence or absence of the ink tank according to the eighth embodiment of the present invention is not provided.

The apparatus is provided with a tank exchange button,
Detection of whether or not the tank replacement button is turned on (S12
If 1) is performed and the answer is “Yes”, the carriage equipped with the ink jet recording head moves from the home position to the tank exchange position in the central portion of the guide shaft (S12).
2). The ink tank replacement work (S123) is performed, and it is detected whether the tank replacement button is turned ON again (S12).
There is 4). When "Yes" is detected, or "N"
When "T" has elapsed since the first tank replacement button was turned on after detecting "o" (S125), the carriage moves to the home position (S126). Since it is different, the T time in S125 can be changed according to the environmental temperature.

The carriage moves to the home position (S
126) and when the ink tank is not attached, the recovery operation by suction and preliminary ejection similar to those in the sixth and seventh embodiments is performed in steps S127, S128, and S129, and thereby the liquid path in the recording head, It is possible to prevent the phenomenon of ink sticking in the common liquid chamber and the supply path. On the other hand, when an ink tank is attached, when performing preliminary ejection (S129) after the suction operation (S128), the temperature rise due to the presence or absence of ink is measured by a thermistor or the like that can measure the ink temperature inside the recording head. By detecting the difference, it can be determined that the ink tank is mounted. In such a case, suction or preliminary ejection may be stopped or suppressed in order to eliminate waste of ink.

As described above, in the eighth embodiment, by showing the operation shown in FIG. 19, when the ink tank is not attached to the head for a long time without the means for detecting the presence or absence of the ink tank. However, it is possible to prevent ink from adhering to the liquid passage in the recording head, the common liquid chamber, and the supply passage. Further, when the ink tank and the head are mounted, waste of ink due to the recovery operation can be eliminated, and stable recording can always be performed.

[0090]

According to the present invention as described above, the above-mentioned technical problem of ink sticking inside the recovery mechanism, and more particularly, the more remarkable technical problem when a water-resistant ink that becomes water-insoluble after drying is used. Can be solved.

Further, according to the present invention, even in the case of performing color recording, the mixed color ink can be discharged from each ejection port by performing the preliminary ejection after the suction, so that the technical problem of color mixture is solved. It is possible to

Further, according to the present invention, the ink in the ink jet head is discharged even if the ink reservoir is not attached for a long time to the ink jet head using the water resistant ink which becomes water insoluble after drying. As a result, the ink is less likely to stick to the ink passage of the inkjet head, and stable ink ejection can be performed promptly after mounting the ink reservoir.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of an example of an inkjet recording apparatus suitable for applying the present invention.

FIG. 2 is a perspective view showing an example of a multicolor integrated type ink jet recording head mounted in the ink jet recording apparatus according to the embodiment of the invention.

FIG. 3 is a cross-sectional view showing a cylinder pump used in an embodiment of the present invention.

FIG. 4A to FIG. 4D are cross-sectional process diagrams for explaining a suction recovery process performed using the cylinder pump according to the embodiment of the present invention.

FIG. 5 is a flowchart for explaining the first embodiment of the present invention.

FIG. 6 is a flowchart illustrating a second embodiment of the present invention.

FIG. 7 is a flowchart for explaining a third embodiment of the present invention.

FIG. 8 is a perspective view showing a main part of another ink jet recording apparatus according to an embodiment of the invention.

FIG. 9 is a schematic perspective view showing an ink ejection port array of an inkjet recording head from the recording member side.

FIG. 10 is a schematic partial perspective view showing the structure of an ink ejection portion of an inkjet recording head.

FIG. 11 is a block diagram of an inkjet recording apparatus according to an embodiment of the present invention.

FIG. 12 is a schematic cross-sectional view showing an inkjet pen in which an ink tank according to an embodiment of the present invention is replaceable.

FIG. 13 is a graph showing the results of investigating the time when the ink tank is not attached to the head and the number of suctions required to restore the function until ink is ejected from all the ink ejection ports after the ink tank is attached. .

FIG. 14 is a flowchart showing an operation when the ink tank according to the fourth embodiment of the invention is not attached.

FIG. 15 is a schematic cross-sectional view showing an inkjet pen provided with detection means for detecting whether or not an ink tank is attached.

FIG. 16 is a flowchart showing an operation when the ink tank according to the fifth embodiment of the invention is not attached.

FIG. 17 is a flowchart showing an operation when the ink tank according to the sixth embodiment of the present invention is not attached.

FIG. 18 is a flowchart showing an operation when the ink tank according to the seventh embodiment of the present invention is not attached.

FIG. 19 is a flow chart showing an operation at the time of replacing an ink tank when a means for detecting the presence or absence of the ink tank according to the eighth embodiment of the present invention is not provided.

[Explanation of symbols]

23 Discharge port 31 Ink Road 34 Common ink chamber 51 ink supply path 54 Filter 56 Tank guide 57 ink tank 59 Absorber 124 cylinders 125 cylinder cap 126 Piston seal 127 piston shaft 128 pistons 2000 Control unit 2025 cylinder pump 5013 motor 5022 Cap

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-278230 (JP, A) JP-A-5-162337 (JP, A) JP-A-5-86315 (JP, A) JP-A-5- 84926 (JP, A) JP-A-4-239649 (JP, A) JP-A-4-128049 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/175 B41J 2 / 165 B41J 2/18 B41J 2/185

Claims (18)

(57) [Claims] 1. A first ink containing urea is ejected.
Urea having different water resistance from the ejection port and the first ink
And a discharge port for discharging the second ink that does not include
Inkjet having a discharge port surface in which a number of discharge ports are arranged
An inkjet recording apparatus that performs recording using a head
The pressure on the discharge port surface,
Suction is performed through a cap capable of collectively sealing the plurality of arranged discharge ports and an opening provided in the cap.
In the operation method for an ink jet recording apparatus having a suction device which performs, in the state in which the cap was pressed against the ejection outlet surface, by performing the suction by the suction means, or said plurality of outlets
And a suction step of sucking the first ink and the second ink; and the first ejection from the plurality of ejection ports with respect to the cap.
In the ejection step of ejecting ink and the second ink, and in a state where the inside of the cap is in communication with the atmosphere, the suction hand
By performing suction by the step, the first ink and the second ink ejected into the cap in the ejection step are
A method of operating an inkjet recording apparatus, which comprises sequentially performing a discharging step of discharging ink . 2. The method of operating an inkjet apparatus according to claim 1 , wherein the first ink and the second ink have different colors from each other. 3. The inside of the cap is in the atmosphere during the discharging step.
The first ink and the second ink in a state of being communicated with the second ink.
2. The method for operating an inkjet device according to claim 1, wherein the ink is discharged . 4. Between the suction step and the discharge step ,
A state where a part of the cap is in contact with the discharge port surface
The method for operating an inkjet apparatus according to claim 1, further comprising the step of driving the suction means by means of. 5. A first ink containing urea is ejected.
Urea having different water resistance from the ejection port and the first ink
And a discharge port for discharging the second ink that does not include
An inkjet head having an ejection port surface in which a number of ejection ports are arranged, an ink reservoir for accumulating the ink supplied to the inkjet head, and the ejection port surface
The plurality of the nozzles arranged on the discharge port surface by being pressed against
It has a cap that can collectively seal the discharge ports.
A method of operating an inkjet apparatus for performing recording using a inkjet head, wherein the first ink and the second ink in the inkjet head are discharged when the ink storage section is not installed. A discharge step , wherein the discharge step is either discharge of ink from the plurality of discharge ports by suction or discharge of ink to the cap from the plurality of discharge ports. A method for operating an inkjet device, comprising: 6. The method of operating an inkjet apparatus according to claim 5 , further comprising a detection step of detecting whether or not the ink storage portion is mounted before the discharging step. 7. The discharge step is connected to the plurality of discharge ports.
From the plurality of ejection ports provided along the ink passage
Produces energy used to eject ink
By driving the energy generating means for
The first ink from the ejection port to the cap.
Ejecting a second ink, the frequency of driving of the energy generating means, said first i from said plurality of outlets
6. The method for operating an inkjet apparatus according to claim 5 , wherein the frequency is lower than the frequency of driving the energy generating unit when recording ink and the second ink to perform recording. Wherein said discharge step, the operation method of the ink jet device according to claim 7, characterized in that it comprises a plurality of driving steps with different frequencies of said energy generating means. Frequency of the drive of the energy generating means in claim 9, wherein the discharge step, according to claim 7, wherein the different between the central portion and the end portion of the discharge port array aligned plurality of ejection ports Inkjet device operating method. 10. The suction in the discharging step comprises:
The method for operating an inkjet apparatus according to claim 5 , wherein the suction force is weaker than 0.5 negative pressure. 11. The method of operating an inkjet apparatus according to claim 5 , wherein the discharging step includes a plurality of suction steps with different suction forces. 12. A first ink containing urea is ejected.
Urine, which has different water resistance between the ejection port and the first ink.
And an ejection port for ejecting a second ink containing no element
An ink jet having an ejection port surface in which a plurality of ejection ports are arranged.
Inkjet recording device that records using the head
It is arranged on the discharge port surface by pressing it against the discharge port surface.
A cap capable of collectively sealing the plurality of discharge ports, suction means for performing suction through an opening provided in the cap, and the plurality of discharge ports for the cap. a discharging means for discharging the second ink and the first ink, by performing the suction by the suction means the cap in the state of being pressed against the discharge port surface, from said plurality of outlets
Sucking the first ink and the second ink ,
Ejecting the first ink and the second ink from the plurality of ejection ports to the cap by ejection means ,
The suction means with the inside of the cap communicating with the atmosphere
And then discharged into the cap .
An ink jet recording apparatus characterized by comprising a control means for controlling so as to discharge the second ink and the first ink. 13. The ink jet apparatus according to claim 12 , wherein the first ink and the second ink have different colors from each other. 14. The inside of the cap is enlarged by the control means.
In a state of communicated with the air, it said against the cap first
Ink jet apparatus according to claim 12, ink and the second ink, characterized in that ejects. 15. A first ink containing urea is ejected.
Urine, which has different water resistance between the ejection port and the first ink.
And an ejection port for ejecting a second ink containing no element
An ink jet head having an ejection port surface in which a plurality of ejection ports are arranged, and an ink storage section for storing the ink supplied to the inkjet head are mounted.
An ink jet device, comprising: a cap capable of collectively sealing the plurality of ejection ports arranged on the ejection port surface by being pressed against the ejection port surface; and an opening provided in the cap. Do suction
And suction means, said suction when the ink reservoir is not attached
Means for ejecting the first ink from the plurality of ejection ports.
An ink jet recording apparatus , comprising: a control unit that controls so as to suck the second ink . 16. The plurality of discharges to the cap
Ejecting the first ink and the second ink from the mouth
The control means further includes a discharge means for discharging the first ink and the second ink from the plurality of discharge ports to the cap by the discharge means.
16. The ink jet recording apparatus according to claim 15, which ejects the ink. 17. A first ink containing urea is ejected.
Urine, which has different water resistance between the ejection port and the first ink.
And an ejection port for ejecting a second ink containing no element
An ink jet head having an ejection port surface in which a plurality of ejection ports are arranged, and an ink storage section for storing the ink supplied to the inkjet head are mounted.
An inkjet device, which is arranged on the ejection port surface by being pressed against the ejection port surface.
A cap capable of collectively sealing the plurality of ejection openings; an ejection unit configured to eject the first ink and the second ink from the plurality of ejection openings to the cap; the discharge when the but not mounted
By means of the plurality of discharge ports to the cap
To eject the first ink and the second ink
An ink jet recording apparatus characterized by comprising a control means for controlling the. 18. The ink jet apparatus according to claim 15 , further comprising a detection unit for detecting whether or not the ink storage section is attached.