JPH07115472B2 - Inkjet device recovery method - Google Patents

Description

The present invention relates to a method for recovering an inkjet device.

[Prior Art] In an inkjet recording apparatus, droplet ejection performance is caused by clogging of an ink ejection port provided in a print head, inclusion of bubbles in an ink supply path leading to the ink ejection port, or the like. May deteriorate, resulting in defective ink ejection.

Therefore, in the conventional ink jet recording apparatus, a suction unit that can face the discharge port is provided outside the discharge port, and ink is sucked from the discharge port or pressure is applied in the ink supply path to flow the ink at a certain flow rate. By discharging from the discharge port, the cause of the above-mentioned defective discharge is removed.

[Problems to be Solved by the Invention] However, in the ink jet recording apparatus,
The print head, the corners in the supply path, and the bumps in the stepped portion have a large flow resistance in the part such as a filter for removing foreign matters provided in the supply path, and therefore a sufficient flow velocity cannot be obtained, and therefore, There is a problem that the bubbles and the like staying in those portions are not discharged and only the ink is discharged, and the cause of the ejection failure may not be properly removed.

Further, in order to eliminate such a cause of ejection failure, it is conceivable to increase the suction force by the suction means or the pressure force by the pressure means for performing the pressure to secure the flow velocity.
Therefore, there is a problem that the size of the device cannot be avoided.

[Means for Solving Problems] According to the present invention, it is possible to solve the problems and secure a sufficient flow velocity without increasing the size of the apparatus, and thus a reliable discharge recovery process can be performed. An object of the present invention is to provide a recovery method for an inkjet device.

Therefore, the recovery method of the inkjet device of the present invention is the recovery method of the inkjet device in which the ink is ejected from the plurality of ejection ports to the medium, and the ink chamber which is commonly communicated with the plurality of ejection ports from the plurality of ejection ports. And a discharge step of discharging the introduced gas together with the ink from the plurality of discharge ports.

[Operation] In the present invention, gas is introduced into the ink chamber through the plurality of ejection ports, and the introduced gas is discharged together with the ink through the plurality of ejection ports. As a result, it is possible to appropriately remove foreign matter in the ink supply path to the ejection port, for example, filters in the supply path, bubbles and dust accumulated in stepped portions, corners and the like of the supply path. Among them, foreign matters including small bubbles are likely to adhere to and stay on the walls near the openings where the ink chamber branches toward the plurality of ejection ports. However, according to the present invention, they can be reliably removed. That is, dust and the like are peeled off by the gas introduced into the ink chamber through the plurality of ejection ports and small bubbles are merged and flowed.However, even if foreign matter remains on the wall, the gas is ejected to the plurality of ejection ports together with the ink. This is because they are removed by the action of a large force when flowing back. In particular, since the flow velocity of gas is usually higher than that of ink due to the flow path resistance, it is preferable to form a gas flow in the ink supply path in order to perform appropriate recovery.

EXAMPLES The present invention will be described in detail below with reference to the drawings.

1 (A) and 1 (B) are an example of the external configuration of an inkjet recording apparatus to which the present invention is applicable and the configuration of an operation panel provided on the front surface of the apparatus, and FIGS. 2 and 3 are shown in FIG. 1 (A). 1) shows an example of the configuration of a recording unit housed inside the apparatus shown in FIG. 2), and in this example, a so-called serial type inkjet recording apparatus is illustrated.

First, in FIG. 1A, 1000 is a device main body 1100, a power switch, and 1200 is an operation panel. Operation panel 1200
As shown in FIG. 3B, an FF switch 1210 and an LF switch 12 for the operator to instruct the conveyance of a recording medium such as paper are displayed.
20, and other command means, such as an online switch 1230 for providing online commands with the master device,
Online lamp 1250 for displaying the online status of the device, alarm lamp 1260 for notifying of abnormalities, etc.
Further, display means such as a ready lamp 1270 for notifying the ready state can be provided.

In FIGS. 2 and 3, reference numeral 1 denotes a head having an ink ejection port on the front surface facing the recording paper P, and a sub tank for supplying ink to a liquid chamber (ink chamber) in the head 1 through a tube 17. 12 and s on the shaft 23 in the figure
The carriage 22 is mounted on a carriage 22 that moves in the same direction, and ink droplets are ejected from the ejection ports in the course of the movement to record on the recording paper P whose recording surface is regulated by the platen 21. Reference numeral 13 is an ink cartridge that is detachably held in the main body 1200, has an ink bag 20 and a plug 19 made of an elastic member inside, and supplies a hollow needle 18 to the plug 19 to an appropriate position to supply a tube. Sub tank through 14
The ink flow path communication state with 12 is obtained.

Here, the ink supplied to the head 1 is kept at a negative pressure as compared with the water head at the ejection port portion. The head of the ink to be supplied is always kept substantially constant by the water level adjusting tube 15, and the ink is supplied to the ejection port side by the surface tension, so that the ink does not recede from the ejection port.
Further, the ink is prevented from leaking from the ejection port due to vibration or the like.

Reference numeral 100 denotes a cap device which is disposed at the home position of the carriage 22, and caps the head 1 when the carriage 22 is positioned at the home position. In this cap device 100, 3 is a head 1
A joint portion that is made of an elastic member that can be joined to the front surface of the, and has a cap 3A for protecting the ejection port when not recording
Reference numerals 7A and 7B respectively denote a gear and a cam for positioning the gear that configures a joint portion conveying mechanism that conveys the joint portion 3 in the T direction in the drawing to join / disengage from the head 1. This joining / disengaging positioning can be performed by, for example, turning on / off the contact 11B of the switch 11 with the cam 7B.

Reference numeral 6 denotes a pump as a suction means, which is connected to the inside of the joint 3 and the inside of the sub tank 12 via the tube 4 and the tube 15 for keeping the ink level in the sub tank 12, respectively, to perform suction. Reference numeral 8 denotes an opening / closing means arranged in the atmosphere open tube 5 for opening the inside of the joint portion 3 to the atmosphere, and for example, a solenoid valve can be used. Further, for example, a vent valve that can be closed is provided between the electromagnetic valve 8 of the tube 5 and the joint portion 3. Reference numeral 9 denotes an operation lever, which engages with a portion capable of closing the ventilation valve and the pump contact 6A, and the pump 6
It has a projection 9A for driving.

In this example, a lever control member including, for example, a spring and a latch is provided, and the lever 9 can be set to an on position, an off position, and an intermediate position between them, and after moving operation from the off position to the on position. When the operation is released, it is held at the intermediate position, and when the operation is released after performing the moving operation from the intermediate position to the on position, it is returned to the off position. Thus, in the ON position, the vent valve 5A is closed and the pump contact 6A is lowered to the maximum to perform the suction operation, and in the intermediate position, the pump contact 6A is returned while the vent valve 5A is closed, and in the OFF position. The vent valve 5A is opened, and the engagement between the pump contact 6A and the projection 9A is released.

Further, as will be described later, the output of the switch 11 and the moving position of the lever 9 are detected by the control unit, and the conveyance of the joint 3 and the driving of the solenoid valve 8 are controlled.

FIG. 4 shows an example of the configuration of the main part of the device of the present invention. In this example, pressure is applied from the outside of the ejection port to introduce air into the recording head 1 and then suction is performed by the pump 6. The ejection recovery process is not performed, and the joining portion 3 is repeatedly joined to and separated from the head 1 for pressurization.

In the figure, 5A is a ventilation valve provided in the middle of the atmosphere release tube 5, which responds to the operation of the operation lever 9 and its portion 9B.
Can be closed by. 3B is an ink absorber provided on the cap 3A and capable of holding ink, and can be formed of, for example, a liquid-absorbing porous material. The cap 3A can be generally formed of various rubber materials such as silicon rubber and butyl rubber.

Reference numeral 30 denotes a filter disposed in the middle of the ink supply tube 17, which collects foreign matter such as dust in the supplied ink and prevents the foreign matter from flowing into the recording head 1 side. Reference numeral 16 is a waste ink absorber disposed in the ink cartridge 13, and receives the waste ink sucked by the pump 6 via the waste ink tube 10.

FIG. 5 is a structural example of a control system of the apparatus according to the embodiment shown in FIG. Reference numeral 200 denotes, for example, a control unit in the form of a microcomputer having a CPU, ROM, RAM, etc., which controls each unit according to a processing procedure stored in the ROM and drives the head 1 for image data received from a host device or the like. Make a record. PS is a paper sensor that detects the recording paper P, and the control unit 200 controls the paper feed by driving the platen roller 21 via the paper feed mechanism 21A including a paper feed motor in response to the detection. CS is a carriage position sensor, and the control unit 200 controls driving of the carriage 22 and positioning to a home position or the like via the carriage motor 22A according to the detected position information.

Reference numeral 7 denotes a transfer mechanism having a drive member such as a motor for transferring the joint 3 in addition to the gear 7A and the cam 7B.
The controller 200 positions the joint with respect to the head 1 in accordance with the contact signal from 11. Reference numerals 1205 and 1255 denote a command means and a display means provided on the operation panel shown in FIG. 1 (B), respectively. LS is a position sensor of the lever 9, and can be provided, for example, in association with the pump contact 6A.

FIG. 6 shows an example of a recovery processing procedure by the control unit 200 shown in FIG. 5, and FIGS. 7 to 9 show an operation example of each unit in the processing.

First, when the carriage 22 is positioned at the home position at the appropriate timing when the power is turned on or during the recording process,
In step S1 in FIG. 6, the joint portion 3 is moved and capped with respect to the head 1. In this state, the operator moves the lever 9 from the off position to the on position in step S3 (time point A in FIG. 7), and waits for a predetermined time until the blinking of the alarm lamp ends in step S5. Step S7
Release the operation of lever 9 with. At the time of moving to the ON position, the suction process from the ejection port 2 is performed, and the ink is filled in the joint portion 3 and the suction tube 4. At this time, in step S9, the solenoid valve 8 is opened for a predetermined time (period B in FIG. 7) to prevent excessive filling.

Next, in step S11, the joining portion transport mechanism 7 is suppressed, and joining / separation of the cap 3A and the discharge port 2 is repeated several times (seventh embodiment).
Period C in the figure). At this time, air is sent into the inside of the head 1 through the ejection port 2 by the cap 3A which is an elastic body. In addition, the cap 3A and the tube 4 are filled with ink, and the volume of the pushing portion is small,
Further, since the filled ink works as an elastic body, the air is effectively pushed. Note that this step S11
As shown in FIG. 8 in connection with the air introduction process of FIG. 8, if the solenoid valve 8 is opened only immediately before the cap 3A of C is separated from the discharge port 2 as shown in FIG. It is possible to remove the negative pressure that is generated instantaneously in (1) and to prevent the introduced air from being discharged (advance of the meniscus) and from scattering the ink.

Next, in step S13, the alarm lamp 1260 and the online lamp 1250 are alternately blinked to notify the operator of the end of the air introduction process. Thus, for example, when the operator moves the lever 9 from the intermediate position to the on position in step S15 (time point E) after the period D, the suction process is started, and after a predetermined time (time point F), the process proceeds to step S17. To open the solenoid valve 8. Then, the operator turns off the lever 9 in step S19, and closes the solenoid valve 8 in step S21.

At this time, since air is introduced to the rear of the ejection port 2, that is, into the ink chamber in the head 1 and the supply tube 17, when negative pressure suction is performed by the pump 6 in this state, the air is ejected at a stretch. As a result, the flow path resistance is substantially reduced and a large suction force is obtained. Therefore,
The cause of ejection failure in the ink supply path from the sub tank 12 to the ejection port 2, that is, foreign matters such as bubbles accumulated in the filter 30, the corners, and the stepped portions are reliably removed.

The reason why the ink is sucked in the processes of steps S3 to S7 to fill the inside of the cap 3A and the suction tube 4 with the ink is that the pressure force due to the joining surely reaches the ejection port 2 when air is introduced to the rear of the ejection port 2. To do so. Further, in the process of step S17, the opening timing of the solenoid valve 8 is delayed relative to the ON timing of the lever 9
For the following reasons.

When the pump 6 is turned on (operating state) at a time point E in FIGS. 7, 8, and 9 with the discharge port 2 sealed by the cap 3A and the ventilation valve 5A and the solenoid valve 8 closed. Then, suction is performed through the suction tube 4, negative pressure (ink suction negative pressure) is generated in the cap 3A and the atmosphere opening tube 5, and the suction process from the ejection port 2 is performed.

At this time, the ink sucked together with the air from the ejection port 2 fills the inside of the cap 3A and leaks from the ink absorber 3B. In addition, the atmosphere open tube 5 may be filled with ink. However, if this state is left as it is, the subsequent ink ejection will be adversely affected.

Therefore, in this example, a time point F when a predetermined time has elapsed from the time point E
Then, the solenoid valve 8 is turned on (opened state) so that the atmosphere open tube 5 is communicated with the atmosphere. Then, the ink leaking from the ink absorber 3B and the ink in the atmosphere open tube 5 are sent to the pump 6 via the suction tube 4.

As shown in FIG. 9, the pressure (suction pressure waveform) in the cap 3A becomes negative with a slight rising angle at the time E when the pump 6 is turned on, and the solenoid valve 8 is turned on (open). At time point F, the atmospheric pressure suddenly returns. Therefore, after the time point F, ink suction is not performed.

Here, the time (FE) from the time E when the pump 6 is turned on to the time F when the solenoid valve 8 is turned on can be controlled by the control unit 200. Further, it may be controlled by a timer for controlling opening / closing of the solenoid valve. This time F-E, that is, the ink suction time, can be appropriately changed by adjusting the control unit 200 or the timer.

In the above embodiment, the operation of the lever 9 is manually performed by the operator, but it is also possible to provide it with appropriate command means and drive means, or to provide drive means during the control process. It is also very easy, and even when the manual operation is performed, the recovery operation can be simplified by providing a start switch or the like so as to start from the broken line at the time point A in FIGS. 7 and 8. it can.

Further, the pressure for pushing the air from the discharge port is made by the cap 3A for preventing the clogging of the nozzle and the mixture of dust and the like, but the pressure for pushing the air from the discharge port 2 is provided separately from the cap 3A. A pressure cap may be provided.

Further, as long as sufficient air is introduced by one-time joining, only one-time joining operation may be performed without repeating the joining.

In addition, in the above embodiment, air is introduced by applying pressure from the outside of the discharge port 2, but air is introduced by setting the inside of the discharge port 2 to a negative pressure state. You can also

FIG. 10 shows another structural example of the main part of the present invention. In the figure, reference numeral 40 is a limiting means which is disposed in the middle of the supply tube 14 and which interrupts or reduces the ink supply, and can be, for example, a solenoid valve. In this example, the solenoid valve 40 is closed and the pump 6 is operated in that state to operate the sub tank.
The supply path from 12 to the ejection port 2 is set to a negative pressure state, and is thus used for introducing suction of ink from the ejection port 2.

The vent valve 5A provided in the middle of the atmosphere release tube 5 responds to the operation of the operation lever 9 and can be closed by its portion 9B.
The ink absorber 3B provided in the cap 3A and capable of holding ink can be formed of, for example, a liquid-absorbing porous material. The cap 3A can be generally formed of various rubber materials such as silicon rubber and butyl rubber.

A filter 30 arranged in the middle of the ink supply tube 17 collects foreign matters such as dust in the supplied ink and prevents the foreign matters from flowing into the recording head 1 side. The waste ink absorber 16 provided in the ink cartridge 13 receives the waste ink sucked by the pump 6 through the waste ink tube 10.

FIG. 11 is a structural example of a control system of the apparatus according to the embodiment shown in FIG. Reference numeral 300 denotes, for example, a control unit in the form of a microcomputer having a CPU, ROM, RAM, etc., which controls each unit according to a processing procedure stored in the ROM and drives the head 1 for image data received from a host device or the like. Make a record. Further, the control unit 300 drives the platen roller 21 via the paper feeding mechanism 21A including a paper feeding motor in response to the paper detection by the paper sensor PS that detects the recording paper P and controls the paper feeding. Further, the control unit 300 controls driving of the carriage 22 and positioning to the home position or the like via the carriage motor 22A according to the carriage position information detected by the carriage position sensor CS.

In addition to the gear 7A and the cam 7B, the control unit 300 uses the transport mechanism 7 having a driving member such as a motor for transporting the joint portion 3, and the head 1 according to the contact signal from the switch 11.
The joint portion 3 is positioned with respect to. 1205 and 1255
Are command means and display means provided on the operation panel shown in FIG. 1 (B), respectively. The position sensor LS can be arranged in relation to the lever 9, for example the pump contact 6A. In addition, the control unit 300 controls opening / closing of the solenoid valve 40 in the recovery process.

FIG. 12 shows an example of a recovery processing procedure by the control unit 300 shown in FIG.

First, when the carriage 22 is positioned at the home position at the appropriate timing when the power is turned on or during the recording process,
In step S101, the joint portion 3 is moved with respect to the head 1 for capping. Next, after closing the solenoid valve 8 in step S103, the solenoid valve 40 is closed in step S105,
The ink supply path from the ink cartridge 13 is shut off.

In this state, in step S107, the lever 9 is moved from the off position to the on position, and then the operation of the lever 9 is released. At this time, the ventilation valve 5A is closed, and as the lever 9 moves to the ON position, the inside of the cap 3A via the suction tube 15 and the ink supply path from the sub tank 12 to the ejection port 2 are in a negative pressure state. To be done. Then, by opening the solenoid valve 8 in step S109, air is sucked from the discharge port 2 through the atmosphere opening tube 5. Then, in step S111, the solenoid valve 40 is opened, in step S113 the solenoid valve 8 is closed, and then in step S115, the lever 9 is moved from the intermediate position to the on position, and the suction process is started. It

At this time, since air is introduced to the rear of the discharge port 2, that is, inside the head 1 and the supply tube 17, when negative pressure suction is performed by the pump 6 in this state, air is expelled from the discharge port 2 at once. Therefore, the flow path resistance is substantially reduced and a large suction force is obtained. Therefore, the sub tank
The cause of ejection failure in the ink supply path from 12 to the ejection port 2, that is, air bubbles and foreign matter accumulated in the filter 30, the corners, and the stepped portions are reliably removed.

As shown in FIG. 13, in addition to the solenoid valve 40, for example, an opening / closing means 42 such as a solenoid valve which can be controlled by a control unit may be provided in the middle of the suction tube 4 to perform the air introduction process.

That is, for example, when the electromagnetic valve 8 is opened and the electromagnetic valve 42 is closed after the electromagnetic valve 40 is closed and the pump 6 is operated, a large negative pressure is applied to the inside of the head 1 via the tube 15. Therefore, the ink in the head 1 flows back to the sub tank 12 side via the supply tube 17, and the air is sucked from the ejection port 2.

After that, the electromagnetic valves 40 and 42 are opened and the electromagnetic valve 8 is closed to operate the pump 6 to obtain the same effect as described above.

Further, as shown in FIG. 14, in addition to the solenoid valve 40, a three-way switching valve 44 is provided in the middle of the suction tube 4, and further in the middle of the three-way switching valve 44 and the supply tube 17, for example, a portion 17A.
A bypass tube 46 that connects the
May be appropriately switched to select the suction path on the suction tube 4 side or the bypass tube 46 side to perform the air introduction process.

That is, for example, if the electromagnetic valve 40 is closed and the electromagnetic valve 8 is opened, the suction path is switched to the bypass tube 46 side by the three-way valve 44, and the pump 6 is operated in this state, then at least the portion 17A is discharged. Air can be taken in through the outlet 2.

Then, the solenoid valve 40 is opened, the solenoid valve 8 is closed, the three-way valve 44 is switched to the suction tube 4 side, and the pump 6 is operated.
The same effect as described above can be obtained.

Further, as shown in FIG. 15, a connecting tube 52 for connecting the supply tube 17 and the suction tube 4 is provided, and a connecting portion with the supply tube 17 is connected to a position for connecting the sub tank 12 side and the head 1 side. A three-way valve 54 that can be switched to a position where the tube 52 side and the head 1 side communicate with each other, and a position where the joint 3 side and the pump 6 side communicate with the connection part with the suction tube 4 and a connecting tube 52 side and pump 6 A three-way valve 56 that can be switched to a position where it communicates with the side may be provided to perform the air introduction process from the discharge port 2.

That is, for example, normally, the three-way valve 54 is set so that the sub-tank 12 and the print head are connected to each other so that ink can be supplied to the head 1, and the three-way valve 56 is set to the state where the joint 3 and the pump 6 are connected.

In the recovery process, the three-way valve 54 is switched to a position where the head 1 communicates with the communication tube 52, and the three-way valve 56 is set to a position where the communication tube 52 communicates with the pump 6. That is, the head 1 communicates with the pump 6 via a part of the supply tube 17, the connecting tube 52 and the suction tube 4 by the two three-way valves.

In this state, if the pump 6 is operated with the joining portion 3 detached from the head 1 or with the cap 3A joined to the head 1 by opening the solenoid valve 8, the head 1
The ink inside is sucked from the supply tube side, and the air is sucked into the head 1 from the ejection port 2.

Then, after returning the three-way valves 54 and 56 to the normal state and performing the recovery operation in the same manner as the above-mentioned example, the same effect can be obtained.

In the examples of FIGS. 10 to 15, the pump 6 is also used as the negative pressure generating means for introducing air into the head 1.
Other negative pressure generating means may be used.

FIG. 16 shows an example thereof, in which a three-way valve 64 is provided in the middle of the supply tube 17, and the three-way valve 64 is communicated with the waste ink absorber 16 via a pump 66 as a negative pressure generating means and a waste ink tube 67. It was possible. The three-way valve 64 can form a path that connects the head 1 side and the pump 66 side. Further, 63 is an operation lever of the pump 66.

In such a configuration, the three-way valve 64 normally connects the sub-tank 12 and the head 1 and maintains a state where ink can be supplied.
In the recovery process, after switching the three-way valve 64 to the communication position between the head 1 and the pump 66, the pump lever 66 is operated by the operation lever 63.
Is operated to generate a negative pressure, and air is taken into the head 1 from the discharge port 2. At this time, the joint portion 3 is separated from the head 1, or the solenoid valve 8 is opened to join the joint portion 3 to the head 1.

The ink sucked by the pump 66 is collected by the waste ink absorber 16 in the ink tank 13 via the waste ink tube 67. Then, the three-way valve 64 may be returned to the normal state and the recovery operation similar to the above may be performed.

In the examples of FIGS. 10 to 16, when a negative pressure is generated inside the discharge port 2 and air is introduced from the discharge port 2, a solenoid valve or a three-way valve is provided at an appropriate position of the supply system as appropriate. Although the switching process is performed to perform the recovery process, the ink supply is performed as follows, paying attention to the fact that the hollow needle 18 is stuck to the plug 19 made of the elastic member of the ink bag 20. You can

17 (A) and 17 (B) show an example of the configuration of the connecting portion between the supply tube 14 and the ink cartridge 13. Normally, the needle hole 18A of the needle 18 enters the space 19A in the stopper 19 of the ink bag 20 to obtain ink conduction as shown in FIG. On the other hand, during the recovery process, the ink cartridge
The positional relationship between the needle 18 and the needle 18 is as shown in FIG.
If the needle hole 18A is positioned within the elastic member of the stopper 19, the stopper 19 closes the needle hole 18A.

18 to 21 show various structural examples of an apparatus capable of performing the position setting shown in FIG.

First, FIGS. 18 (A) and (B) show a fitting guide 24 of the apparatus main body 1000 for receiving the ink cartridge 13,
Click points 24A and 24B for holding the ink cartridge 13 are provided at two positions, that is, a position where the supply path is cut off and a position where the supply path is electrically connected, while the ink cartridge 13 has a locking portion 13 that is locked by these click points.
A is provided. Further, 29 is a needle position fixing member fixed to the main body 1000.

By doing so, if the ink cartridge 13 is positioned by an operator's operation or an appropriate driving means in relation to the recovery process, the ink blocking state by the click point 24A (FIG. (B)) or the click point 24B. The conductive state ((A) in the figure) is obtained.

19 (A) and 19 (B), a stopper 25 which can be moved up and down is provided below the fitting path of the ink cartridge 13, and when the stopper 25 is descending, an ink conduction state (FIG. 19 (A)) is obtained. This is so that the ink blocking state (FIG. 7B) can be obtained when the stopper 25 is in the raised position. In addition, this stopper 25 is an appropriate part other than the fitting path,
For example, it may be provided on the fitting guide 24.

20 (A) and 20 (B) show the ink blocking state by aligning the alignment mark 26 provided on the ink cartridge 13 with the alignment mark 27 provided near the fitting portion of the main body 1000 (FIG. 20 (B)). ) Is obtained. If the marks are not fitted and fitted to the innermost part, a conduction state as shown in FIG.

Further, the position may be set by the mark on the main body side and the edge of the ink cartridge 13.

FIGS. 21A and 21B show an example in which the attachment 28 is detachably attached to the ink cartridge 13 for positioning. Depending on whether or not the attachment 28 is attached, the connection state (the same figure (B)) or the conduction state (the same figure (A))
Can be obtained.

According to the examples shown in FIGS. 17 to 21, not only can the ink supply path be reliably blocked, but it is also very easy to obtain the blocked state. Further, these examples can be widely applied not only to a device that sucks ink from the outside of the discharge port 2, but also to a device that performs recovery processing by pressurizing the inside of the discharge port and pushing out ink.

In the above embodiment, the air is introduced from the outside of the discharge port 2. However, since the discharge port 2 has a large flow path resistance as described above, the air introduction process may not be performed quickly. Conceivable. Therefore, in this example, the front surface 1A of the head 1 is configured as follows.

22 (A), (B) and (C) are three examples of the configuration of the head front surface 1A. In the figure, (A) is a general configuration example of the head front surface 1A, and this configuration may be used when the air introduction process is not urgent. However, when rapid and reliable introduction is desired, as shown in (B) and (C) of the same figure, a dummy ejection having a cross-sectional area larger than that of the ejection port 2 and not used for actual printing is provided. The exit 2A should be provided.

That is, since the holding force of the meniscus at the discharge port is determined by the surface tension, the larger the cross-sectional area (radius r for a circular discharge port), the smaller the holding force of the meniscus,
Therefore, it is easy to take in air when introducing pressure or negative pressure of air. Needless to say, the number and placement of the dummy ejection ports 2A can be arbitrarily selected as desired.

In the above description, the case where the present invention is applied to the serial type ink jet recording apparatus has been described, but it goes without saying that the present invention can be applied to any type of ink jet recording apparatus that ejects ink from an ejection port to perform recording. . For example, it may be a full-multi type device having a plurality of ejection units in the width direction of the recording paper.

Further, in the above description, the operation of the pump and the like is performed manually, but it is also easy to operate it in the control process by using an appropriate drive means.

[Effects of the Invention] As described above, according to the present invention, it is possible to realize a recovery method for an inkjet device that can perform a reliable ejection recovery process without increasing the size of the device.

[Brief description of drawings]

1 (A) and 1 (B) are a perspective view and a front view, respectively, showing an outer appearance of an inkjet recording apparatus to which the present invention is applicable and an example of a configuration of an operation panel provided on the front surface of the apparatus. FIG. 2 and FIG. 3 are a perspective view and a plan view showing one structural example of the recording unit housed in the apparatus shown in FIG. 1 (A). FIG. 4 is a schematic view showing one structural example of an apparatus for introducing air from the outside of the discharge port as a main part of the apparatus of the present invention. FIG. 5 is a block diagram showing one structural example of the control system in the embodiment shown in FIG. FIG. 6 is a flowchart showing an example of a recovery processing procedure by the control system shown in FIG. 7 to 9 are timing charts showing the operation of each part in the recovery processing. FIG. 10 is a schematic view showing an example of an apparatus in which the inside of the discharge port is in a negative pressure state and air is taken in from the discharge port as another configuration example of the main part of the device of the present invention. FIG. 11 is a block diagram showing a structural example of a control system in the embodiment shown in FIG. FIG. 12 is a flowchart showing an example of a recovery processing procedure by the control system shown in FIG. 13 to 16 are schematic views showing four examples of other configurations of the apparatus in which the inside of the discharge port is in a negative pressure state and air is taken in from the discharge port. 17 (A) and 17 (B) are cross-sectional views showing a connected state of the ink supply tube and the ink cartridge. FIGS. 18 (A) and (B) to FIGS. 21 (A) and (B) are four examples of the configuration of the device capable of setting the ink cartridge position shown in FIGS. 17 (A) and (B). FIG. 22 (A), (B) and (C) are front views showing three examples of the configuration of the front surface of the head. 1 ... Head, 2 ... Discharge port, 3 ... Joint, 3A ... Cap, 3B ... Ink absorber, 4,15 ... Ink suction tube, 5 ... Atmosphere release tube, 5A ... Vent valve , 6 ... Pump, 6A ... Pump contact, 7 ... Joint transport mechanism, 8 ... Solenoid valve, 9 ... Operating lever, 10 ... Waste ink tube, 12 ... Sub tank, 13 ... Ink cartridge, 14,17 ... Ink supply tube, 16 ... Waste ink absorber, 18 ... Needle, 18A ... Needle hole, 19 ... Plug, 19A ... Space part, 20 ... Ink bag, 22 ... Carriage, 24 …… Mating guide, 30 …… Filter, 40,42 …… Solenoid valve, 44,54,64 …… Three-way switching valve, 66 …… Pump, 200,300 …… Control unit, 1000 …… Device body, 1200… …control panel.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Akira Miyagawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Riki Abe 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Nori Hattori 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A-58-14762 (JP, A)

Claims (1)

[Claims] 1. A method of recovering an ink jet device for ejecting ink from a plurality of ejection ports to a medium, wherein an introducing step of introducing gas from the plurality of ejection ports into an ink chamber commonly communicating with the plurality of ejection ports. And a discharge step of discharging the introduced gas together with the ink from the plurality of discharge ports, the recovery method of the inkjet device.