JP2002086746A - Ink ejection recovery device and ink-jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an image stably with a good quality by preventing deterioration of the ejection recovery process function of a recording head. SOLUTION: A suctioning tube 25 interlocked with a suctioning pump 26, is provided on both end parts in the longitudinal direction of a suctioning cap 21 so that an ink supplied to a recording head 3 is provided as an even ink flow in the suctioning cap 21 by uniformly suctioning the inside of the suctioning cap 21 by uniformly suctioning the inside of the suctioning cap 21 for recovering the ejection function of each nozzle stably. The ink stagnated in the suctioning cap 21 is suctioned from both end parts of the suctioning cap 21 so as to be discharged stably by opening the inside of the suctioning cap 21 to the atmosphere by an atmosphere opening pipe 28 interlocked with an atmosphere opening valve 27 in the center part of the suctioning cap 26.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink ejection recovery device for a recording head for ejecting ink to form characters and images on a recording material, and an ink jet recording device.

[0002]

2. Description of the Related Art In an ink jet printer, a mechanism for maintaining the performance of a recording head for discharging ink is indispensable. The main functions are a cap function to prevent drying of the nozzle that discharges ink, a discharge recovery function that sucks ink from the ink cartridge through the cap function and fills the inside of the print head, and a wiper function that wipes the nozzle surface. It is composed of

In recent years, the speed of image formation has been increased, and by increasing the number of nozzles of a recording head, the number of nozzles of a recording head has been increased to improve the throughput by skipping more ink droplets. In the direction. Accordingly, the shape of the recording head is elongated in the nozzle row direction, and accordingly, the cap for covering the nozzle of the maintenance / recovery mechanism is also elongated. This suction cap 21 is usually held by an outer frame 22, as shown in the sectional view of FIG.
A cap body 23 made of an elastic material such as rubber or elastomer, an absorbent body 24 attached to the inside of the cap body 23 and having a water retention property for moisturizing, and a suction port penetrating through the cap body 23 to be absorbed. A suction tube 25 provided at the lower part of the body 4, a suction pump 26 attached to the suction tube 25, and provided to penetrate through the cap body 23 and the absorber 24, and have an atmosphere opening valve 27 at a tip end. And a tube 28.

When the ejection recovery process of the recording head 3 is performed by the suction cap 21, the nozzle surface 12 having the nozzle row for ejecting the ink of the recording head 3 is moved to the cap body 2.
3 and the air release valve 27 is closed, the suction pump 26 is driven to suck air from the cap body 23 to make the inside of the cap body 23 a negative pressure, and to print from the ink tank connected to the print head 3. The ink is supplied to the head 3. The ink supplied to the recording head 3 flows out into the cap body 23 by the suction force of the suction pump 26 and fills the inside of the cap body 23 and the suction tube 25. If the suction cap 21 is removed from the recording head 3 in this state, a large amount of ink remains on the nozzle surface 12 of the recording head 3, and the load when the ink remaining on the nozzle surface 12 is wiped with a wiper in the next process increases. In order to prevent this, before removing the suction cap 21 from the recording head 3, the air release valve 27 of the air release pipe 28 is opened, and the suction pump 26 is further driven. Suction pump 2 with air release valve 27 open
6 is driven to open the cap body 23 from the atmosphere opening pipe 28.
Then, the air is sucked from the ink tank, and the ink in the cap body 23 and the ink absorbed by the absorber 24 are sucked and discharged without sucking the ink from the ink tank. This ink suction is performed for a predetermined time, and the cap is removed in a state where the ink in the cap body 23 is as low as possible.
The amount of ink remaining on the nozzle surface 12 is reduced. Then, the ink remaining on the nozzle surface 12 in the next step is wiped off with a wiper. In this manner, the ink remaining on the nozzle surface 12 is wiped while the amount of the ink remaining on the nozzle surface 12 is minimized, so that it is possible to prevent the ink from remaining on the nozzle surface 12 and deteriorating the ejection characteristics.

In order to effectively perform the ejection recovery processing of the recording head 3 for each nozzle, for example, Japanese Patent Laid-Open No. 7957/1995
The ink jet recording apparatus disclosed in Japanese Patent Application Laid-Open Publication No. 12-123456 has a suction tube 25 at a position distant from a position facing an ink supply port for supplying ink from an ink tank to the recording head 3.
Is provided, and the pressure of the cap main body 23 during suction by the suction tube 25 is made uniform to make the flow of ink passing through each nozzle uniform.

[0006]

However, when the shape of the recording head 3 is elongated in the nozzle row direction and the shape of the suction cap 21 is also elongated, the absorber 24 in the cap body 23 is necessarily elongated. Cap body 23
When sucking ink with the inside open to the atmosphere,
Absorber 24 at a position away from the suction port of suction tube 25
It is not easy to suck and discharge the ink that has been absorbed by the ink, and ink that remains while being absorbed by the absorber 24 occurs. The ink 13 remaining in the absorber 24 gradually increases when the ejection recovery processing of the recording head 3 is repeatedly performed, and the water evaporates to a high viscosity, thereby rapidly deteriorating the absorption performance. In recent years, pigment-based inks have been frequently used from the viewpoint of improving image quality.
Higher viscosity is more remarkable than dye ink. For this reason, the ejection recovery processing function of the recording head is reduced.

An object of the present invention is to provide an ink jet recording apparatus and an ink jet recording apparatus which can improve the above disadvantages and can stably form a high-quality image by preventing the deterioration of the recording head ejection processing function. It is the purpose.

[0008]

An ink ejection recovery device according to the present invention is mounted on a carriage, covers the nozzle surface of a recording head with a suction cap, and recovers the ink ejection function of the nozzle by applying a negative pressure to the inside of the suction cap. In the ink ejection recovery device, a suction tube connected to a suction pump is provided at both ends in a longitudinal direction of the suction cap, and an atmosphere opening pipe connected to an atmosphere opening valve is provided at a center portion of the suction cap.

Another ink discharge recovery device according to the present invention is a device mounted on a carriage, which covers a nozzle surface of a recording head with a suction cap, and restores the ink discharge function of the nozzle by applying a negative pressure to the inside of the suction cap. Wherein a suction tube connected to a suction pump is provided at a central portion of the suction cap, and an atmosphere opening pipe connected to an atmosphere opening valve is provided at both ends in a longitudinal direction of the suction cap.

The suction cap has a cap body formed of an elastic material and an absorber mounted inside the cap body, and a suction port of a suction tube is provided at a lower portion of the absorber through the cap body. It is desirable to provide an air inlet for the open-to-atmosphere pipe through the cap body and the absorber.

An ink jet recording apparatus according to the present invention includes any one of the above-described ink discharge recovery devices.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An ink jet printer according to the present invention has a cyan C, a magenta M, a yellow Y and a black Bk.
There are four ink cartridges respectively containing the respective color inks, four recording heads having a plurality of nozzles to which ink is supplied from each ink cartridge, and a carriage on which the ink cartridges and the recording heads are mounted.

Outside the print area of the carriage, there is provided a suction cap of the ejection recovery device for the recording head. The suction cap is held by the outer frame, the cap body made of an elastic material, the absorber attached inside the cap body, and the suction port penetrating through both ends in the longitudinal direction of the cap body to form the suction port. Two suction tubes provided at the lower part, a suction pump connected to each suction tube, and an air inlet provided through the center of the cap body and the absorber, and having an air release valve at the tip. And an open tube.

When the recovery operation of the recording head is performed by the suction cap, the air release valve is closed while the nozzle surface of the recording head is covered by the cap body, and the suction pump is driven to release air in the cap body by two. The inside of the cap body is made negative pressure by suction with the suction tube, and ink is supplied to the recording head from an ink cartridge connected to the recording head. The ink supplied to the recording head flows out of each nozzle as a uniform ink flow into the cap body by the suction force from the suction port of each suction tube, and the ejection function of each nozzle is restored. The ink flowing out of each nozzle fills the inside of the cap body and the suction tube. In this state, the air release valve of the air release pipe is opened and the suction pump is driven to suck and discharge the ink in the cap body and the ink absorbed by the absorber.

[0015]

FIG. 1 is a block diagram of one embodiment of the present invention.
As shown in the figure, the ink jet printer 1 has four ink cartridges 2 containing inks of respective colors of cyan C, magenta M, yellow Y and black Bk.
And four recording heads 3 each having a plurality of nozzles and supplied with ink from each ink cartridge 2, a carriage 4 on which the ink cartridge 2 and the recording head 3 are mounted, and a paper feed tray 5a containing recording paper, A transport roller 8 for transporting recording paper from a manual feed table 6 to a printing unit 7; and a discharge roller 10 for discharging printed recording paper to a paper output tray 9.
Having. When printing the image data sent from the host device on the recording paper, the carriage 4 scans the carriage guide roller 11 while scanning the carriage 4 with the nozzles of the recording head 3 on the recording paper sent to the printing unit 7. And ejects ink according to the image data to record characters and images.

Outside the printing area of the carriage 4, there is provided a suction cap 21 of the ejection recovery device for the recording head 3, as shown in the perspective view of FIG. The suction cap 21 is an outer frame 22
A cap body 23 formed of an elastic material such as rubber or an elastomer, and an absorber 24 attached to the inside of the cap body 23 and having a function of retaining water and defoaming ink for moisture retention. As shown in the cross-sectional view of FIG. 3, two suction tubes 25a and 25b, each of which penetrates both ends in the longitudinal direction of the cap main body 23 and whose suction ports are provided at the lower part of the absorber 4, and the suction tubes 25a and 25b. Suction tube 25c connected to suction pump 26 by connecting 25b
An air inlet is provided through the center of the cap body 23 and the absorber 24, and has an atmosphere opening pipe 28 having an atmosphere opening valve 27 at the tip.

The recording head 3 is moved out of the printing area by the carriage 4 when recording is not being performed, and the nozzle surface 12 of the recording head 3 having the nozzle array for ejecting ink is covered with the cap body 23 of the suction cap 21. Drying of each nozzle is prevented. When performing the ejection recovery process of the recording head 3 with the suction cap 21, the atmosphere opening valve 27 is closed with the nozzle surface 12 of the recording head 3 covered with the cap body 23, and the suction pump 26 is driven to drive the cap body 23. Is sucked by the two suction tubes 25a and 25b to make the inside of the cap body 23 a negative pressure, and ink is supplied to the recording head 3 from the ink cartridge 2 connected to the recording head 3. When the air in the cap body 23 is sucked by the suction tubes 25a and 25b to make a negative pressure,
The suction ports of the suction tubes 25a and 25b are
3, the inside of the cap body 3 can be uniformly sucked. Recording head 3
Is supplied from each nozzle to the cap body 23 by the suction force from the suction ports of the suction tubes 25a and 25b.
The ink flows out as a uniform ink flow inside, and the ejection function of each nozzle is restored. The ink flowing from each nozzle fills the inside of the cap body 23 and the suction tube 25.
In this state, the air release valve 27 of the air release pipe 28 is opened to drive the suction pump 26. When the suction pump 26 is driven with the atmosphere release valve 27 opened, air enters the cap body 23 through the atmosphere release pipe 28 and absorbs the ink in the cap body 23 without sucking the ink from the ink cartridge 2. The ink absorbed by the body 24 is sucked and discharged. Ink and absorber 2 in cap body 23
When sucking and discharging the ink absorbed in 4,
The air injection port of the open-to-atmosphere pipe 28 is provided at the center of the cap body 23, and the suction ports of the suction tubes 25a and 25b are provided at both ends in the longitudinal direction of the cap body 23. Certain ink and absorber 2
The ink absorbed by the suction tube 25 is supplied to the suction tubes 25a, 25
b can be sucked and discharged. Further, the distance from the air inlet to the suction ports of the suction tubes 25a and 25b is almost half of the entire length of the cap body 23, so that the resistance applied to the air flow injected from the air inlet can be reduced. The remaining ink can be sucked and discharged without deteriorating the suction performance of the tubes 25a and 25b. Therefore, it is possible to prevent the ink from remaining in the cap body 23 and the absorber 24, and to prevent the ejection function of each nozzle of the recording head 3 from being lowered. In addition, a high-quality image can be stably formed by ejecting ink from the nozzles of the recording head 3 whose ejection function has been restored.

In the above embodiment, the suction tubes 25a, 25b
Are described at the longitudinal ends of the cap body 23, and the air inlet of the air release pipe 28 is provided at the center of the cap body 23, as shown in the cross-sectional view of FIG. Even if the suction ports of the suction tubes 25a and 25b are provided at the center of the cap body 23 and the air injection ports of the air release pipe 28 are provided at both ends in the longitudinal direction of the cap body 23, as in the above-described embodiment, The remaining ink can be sucked and discharged without deteriorating the suction performance of 25b.

[0019]

As described above, according to the present invention, the inside of the suction cap can be uniformly sucked by providing the suction tubes connected to the suction pump at both ends in the longitudinal direction of the suction cap. The ink supplied to the print head can flow out from each nozzle as a uniform ink flow into the suction cap by the suction force from the suction port of each suction tube, and the ejection function of each nozzle can be restored stably. Can be.

Further, by providing a suction tube connected to a suction pump at both ends in the longitudinal direction of the suction cap and providing an air release pipe connected to an air release valve at the center of the suction cap, the suction tube remains in the suction cap. The sucked ink can be stably discharged from both ends of the suction cap. In addition, the distance from the air inlet to the suction port of the suction tube is almost half of the entire length of the suction cap, so that the resistance applied to the air flow injected from the air inlet can be reduced, and the suction performance of the suction tube can be reduced. The remaining ink can be sucked and discharged without deteriorating the ink.

A suction tube connected to a suction pump is provided at the center of the suction cap, and an atmosphere opening pipe connected to an atmosphere opening valve is provided at both ends in the longitudinal direction of the suction cap, so that the air is injected from the air inlet. The resistance applied to the air flow can be reduced, and the remaining ink can be sucked and discharged without deteriorating the suction performance of the suction tube.

Further, the suction cap has a cap body formed of an elastic material, and an absorber mounted inside the cap body, and a suction port of the suction tube penetrates the cap body to a lower portion of the absorber. By providing an air inlet for the open-to-atmosphere pipe through the cap body and the absorber, the ink that has been absorbed by the absorber and remaining ink can be stably sucked and discharged. The high-viscosity ink can be prevented from staying.

Further, by providing this ink ejection recovery device in an ink jet printer, a facsimile, or the like,
The ink discharge function of the recording head can be recovered stably, and a high-quality image can be formed stably.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an ink jet printer according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a configuration of a suction cap.

FIG. 3 is a cross-sectional view illustrating a configuration of a suction cap.

FIG. 4 is a cross-sectional view illustrating a configuration of another suction cap.

FIG. 5 is a cross-sectional view showing a configuration of a suction cap of a conventional example.

DESCRIPTION OF SYMBOLS 1; inkjet printer, 2; ink cartridge, 3; recording head, 4; carriage, 21; suction cap, 22; outer frame, 23; cap body, 24; absorber, 25; Suction pump, 27; atmosphere release valve, 28; atmosphere release pipe.

Claims (4)

[Claims] 1. An ink ejection recovery device which is mounted on a carriage, covers a nozzle surface of a recording head with a suction cap, and recovers an ink ejection function of a nozzle by applying a negative pressure to the inside of the suction cap. A suction tube connected to a suction pump, and an air release pipe connected to an air release valve at the center of the suction cap. 2. An ink ejection recovery device which is mounted on a carriage, covers a nozzle surface of a recording head with a suction cap, and restores the ink ejection function of the nozzle by applying a negative pressure to the inside of the suction cap. And a suction tube connected to an air release valve at both ends of the suction cap in the longitudinal direction. 3. The suction cap has a cap body formed of an elastic material, and an absorber mounted inside the cap body, and a suction port of the suction tube penetrates the cap body and is located below the absorber. The ink ejection recovery device according to claim 1, wherein the air injection port of the open-to-atmosphere pipe is provided to penetrate the cap body and the absorber. 4. An ink jet recording apparatus comprising the ink ejection recovery device according to claim 1, 2 or 3.