JPH09239995A - Capping device for inkjet recording head - Google Patents

Abstract

(57) Abstract: To simplify the flow path configuration for negative pressure supply of a capping device of a recording head having black and color nozzle opening arrays. A cap member (42) has a single ink suction port (53) and a single air opening port (54) on the bottom surface, the lower surface is in contact with the upper surface of an ink absorbing sheet (58), and the upper surface is a nozzle of a recording head. A partition 42a integrally formed with the cap member main body is provided so as to contact the boundary between the color nozzle opening row 31 and the black nozzle opening row 32-34 of the plate 26. The negative pressure supplied to the single ink suction port 53 causes the ink absorbing sheet 5 at the bottom of the cap member 42 to be discharged.
Since it acts on each of the regions 61 and 62 through the partition 8,
Ink is discharged from all the nozzle opening rows 31 to 34 by the single ink suction port 53 regardless of 2a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus having a recording head which moves in the width direction of a recording sheet, and ejecting ink droplets onto the recording sheet in accordance with print data to form an image. The present invention relates to a capping device suitable for a recording device equipped with a head.

[0002]

2. Description of the Related Art An ink jet recording head body is extremely small in size, and color printing is possible by changing ink colors. Therefore, black, yellow, cyan, and magenta inks are ejected to a common head holder. Inkjet color printers that can perform full-color printing as well as text printing with black ink have been put into practical use by providing a recording head capable of printing. In such an ink jet recording head, ink pressurized in a pressure generating chamber is ejected from a nozzle as an ink droplet onto a recording sheet to record print data. There is a problem that printing failure occurs due to increase in viscosity, solidification of ink, adhesion of dust, and inclusion of bubbles.

Therefore, the ink jet recording apparatus is
Usually, it is provided with a capping means for sealing the nozzle openings of the recording head during non-printing, and a cleaning means for cleaning the nozzle plate if necessary. This capping means not only functions as a lid for preventing the above-mentioned nozzle opening from drying, but when the nozzle opening is clogged, the capping means seals the nozzle plate to prevent negative pressure from the suction pump. It also has a function of supplying ink and forcibly ejecting ink from the nozzle openings to eliminate clogging of the nozzle openings.

However, when a negative pressure is applied to the nozzle openings to forcibly discharge the ink from the nozzle openings, inks of different colors, especially black ink, infiltrate into the nozzle openings for ejecting the color inks, resulting in color printing. There is a problem of degrading quality.

Therefore, as disclosed in Japanese Patent Laid-Open No. 6-101961, the capping means is divided into two chambers by ribs at the boundary between the nozzle opening for ejecting black ink and the nozzle opening for ejecting color ink. , A capping means has been proposed which is configured to supply negative pressure to each room independently.

[0006]

However, a mechanism for switching and supplying the negative pressure to the two chambers is required, which not only complicates the structure, but also the black ink recording head and the color ink recording head. Since negative pressure is sequentially supplied to the recording head, there is a problem that the discharge recovery operation takes time.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a simple ink jet recording apparatus having a structure that does not cause color mixture of black ink and color ink. That is.

[0008]

In order to solve such a problem, according to the present invention, a recording head having an ink absorbing sheet on the bottom surface and a nozzle opening array for black ink and a nozzle opening array for color ink is provided. In a capping device provided with a cap member for sealing
The cap member has a single ink suction port on the bottom surface and a single atmosphere opening port, the lower surface is in contact with the upper surface of the ink absorbing sheet, and the upper surface is the color nozzle of the nozzle plate of the recording head. A partition portion integrally formed with the cap member main body is provided so as to contact the boundary between the opening row and the black nozzle opening row.

[0009]

Since the negative pressure supplied to the single ink suction port acts on each region through the ink absorbing sheet at the bottom of the cap member, the single ink suction port can be used to open all the nozzle openings regardless of the partition. Ink can be forced out of the row.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The details of the present invention will be described below with reference to illustrated embodiments. FIG. 1 shows an embodiment of an ink jet recording apparatus to which the present invention is applied. In the drawing, reference numeral 1 is a carriage connected to a motor 3 via a timing belt 2 and guided by a guide member 4 to a platen. 5 is configured to be reciprocable in the axial direction.

A recording head 7 is mounted on the side of the carriage 1 facing the recording paper 6, and an ink cartridge 8 for supplying ink to the recording head 7 is detachably provided on the upper surface.

On the other hand, a capping device 10 for sealing the nozzle opening rows 31 to 34 of the recording head 7 in the non-printing area.
Is provided and the nozzle opening rows 31 to 3 during the rest period are provided.
In addition to functioning as a cap means for preventing drying of No. 4, it also functions as an ink receiver at the time of flushing operation, and causes the negative pressure from the suction pump 11 to act on the recording head 7.
It has a function as a suction unit for forcibly discharging the ink from the recording head 7.

FIGS. 2 (a) and 2 (b) respectively show an embodiment of the ink jet recording head described above. The unit 21 for ejecting black ink and the yellow for enabling color printing are shown. The units 22, 23, 24 for ejecting cyan, magenta, and cyan inks are provided in the flow path unit 25 in which the nozzle opening rows 31, 32, 33, 34 are formed, and the black ink is discharged from the nozzle opening row 31 of the nozzle plate 26. , And the nozzle opening row 32,
Yellow, cyan, and magenta ink droplets are ejected from 33 and 34, respectively.

FIGS. 3 and 4 show an embodiment of the capping device 10 described above. In FIG. 3, reference numeral 40 is a slider, which follows the movement of the carriage 1 when the carriage 1 moves to the non-printing area. The upper surface of the base 41 in the horizontal direction,
And is configured to move in the vertical direction.

A cap member 42, which will be described later, for sealing the nozzle opening rows 31 to 34 of the recording head 7 is provided in one half of the upper surface on the printing area side (left side in the figure), and the outer area (right side in the figure). In the other half, a valve unit 57 that is opened and closed by an operating rod 64 is provided, and a flag piece 44 that abuts the carriage 1 is provided at the outermost end.

The slider 40 has a convex piece 45 at the lower end, contacts the guide surface 46 of the base 41 and slides on the surface thereof, and the carriage 1 moves to the side of the printing area side. It has a protrusion 47 orthogonal to the direction and one end is a long groove 48.
The arm 49 is rotatably supported by the base 41 and is rotatably supported by the other end of the arm 49. The compression spring 50 inserted between the base 41 and the arm 49 always moves the print area side upward. It is configured to urge to take a substantially horizontal posture.

On the other hand, the guide surface 46 of the base 41 has a low position 46a and a high position so that the cap member 42 can occupy a position separated from the nozzle plate 26 and two positions in which the cap member 42 elastically contacts the nozzle plate 26. It is formed by the place 46b and the slope 46c connecting these.

The cap member 42 is made of a synthetic resin such as rubber having ink resistance and is formed as a cup having an atmosphere communication port 53 and an ink suction port 54 on the bottom surface.
The slider 40 is attached to the slider 40 by being fitted into a support frame 52 which is held horizontally by two springs 65, 65.

The atmosphere communication port 53 and the ink suction port 5
4 are connected to a valve unit 57, which will be described later, and a common suction pump 11 by conduits 55 and 56 formed integrally with the cap member 42, respectively.

FIG. 5 is an enlarged view of the cap member 42 described above. The bottom part of the ink absorption sheet 58 is made of a porous material having ink resistance and ink absorption.
Is inserted so as to cover almost the bottom surface.

The lower surface is in contact with the upper surface of the ink absorbing sheet 58, and the upper surface is in contact with the boundary between the color nozzle opening rows 32 to 34 and the black nozzle opening row 31 of the nozzle plate 26, and is integrated with the cap member main body. The partition portion 42a configured as described above is formed, and the space on the nozzle opening side in the cap is divided into a black sealing region 62 and a color sealing region 61.

In this embodiment, when it is necessary to forcibly discharge the ink from the recording head 7, the pump unit 1 is in the capped state (FIG. 6).
When 1 is operated and a negative pressure is applied to the ink suction port 56,
A negative pressure is also applied to each of the sealing regions 61 and 62 via the ink absorbing sheet 58.

As a result, the black nozzle opening row 3 is formed.
1, and ink droplets are ejected from the color nozzle opening rows 32 to 34, and a part thereof is sucked by the ink suction pump 11 from the ink suction port 55 via the absorption sheet 58 and discharged to a waste ink tank (not shown). The black nozzle opening row 31 and the color nozzle opening rows 32-34 are separated by a partition 42.
Since it is divided by a, the ink ejected from the nozzle opening row of one group cannot flow into the other nozzle opening row.

Therefore, the black ink and the color inks are not mixed with each other, and the dust and paper dust adhering to the black nozzle opening row 31 and the color nozzle opening rows 32 to 34 are cleaned and further recorded. The bubbles in the head 7 are discharged to the cap member 42 together with the ink.

At the stage where the forced ejection of ink is completed,
When the carriage 1 is further moved from the capped state to the non-printing area side, the operating rod 64 causes the valve unit 5 to move.
Since 7 is opened, the atmosphere flows in from the atmosphere communication hole 56,
The ink remaining on the ink absorbing sheet 58 is discharged from the ink suction port 56 without applying an excessive negative pressure to the nozzle openings 31 to 34.

In the above-described embodiment, the color nozzle opening rows 32 to 34 are divided into one group, but as shown in FIG. 7, the color nozzle opening rows 32 and 33 are divided. , 34 at the boundary of 34
If the nozzle opening rows 31 to 34 for black, yellow, cyan, and magenta are separated by providing 2b and 42c, it is possible to prevent not only black and color ink but also color mixing between color inks.

Further, in the above-mentioned embodiment, the partition 4
The black nozzle opening row and the color printing nozzle opening row are divided by 2a, as shown in FIG.
As shown in (b), it is clear that the same effect can be achieved even if only the contact portions 42d and 42e with the nozzle plate 26 are made independent and the main body is integrally formed.

[0028]

As described above, in the present invention, the cap member has the single ink suction port on the bottom surface and the single atmosphere opening port, and the lower surface is in contact with the upper surface of the ink absorbing sheet. Further, since the partition is provided so that the upper surface is in contact with the boundary between the color nozzle opening row and the black nozzle opening row of the nozzle plate of the recording head, the black ink and the color ink are not mixed, and the partition Ink can be forcibly discharged from all the nozzle opening rows by the negative pressure from the ink suction port, and the flow path configuration for negative pressure supply can be simplified.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of an ink jet recording apparatus using a capping device of the present invention.

2A and 2B are views showing an embodiment of an ink jet recording head used in the above apparatus, respectively.

FIG. 3 is a perspective view showing an embodiment of the capping device of the present invention.

FIG. 4 is a sectional view of the capping device of the above.

5A to 5C are a longitudinal sectional view, a top view, and a sectional view taken along line AA showing an embodiment of a cap member used in the capping device, respectively.

FIG. 6 is a diagram showing a state in which the recording head is sealed by the same cap member.

FIG. 7 is a sectional view showing another embodiment of the present invention.

8A and 8B are a sectional view and a plan view, respectively, showing another embodiment of the present invention.

[Explanation of symbols]

 1 Carriage 7 Recording Head 10 Capping Device 11 Pump Unit 42 Cap Member 42a Partition Part 55 Ink Suction Port 56 Atmosphere Release Port 58 Ink Absorption Sheet

Claims (2)

[Claims] 1. A capping device having an ink absorbing sheet on a bottom surface and provided with a cap member for sealing a recording head having a nozzle opening row for black ink and a nozzle opening row for color ink, wherein the cap member is , A single ink suction port on the bottom surface, and a single atmosphere opening port, the lower surface is in contact with the upper surface of the ink absorption sheet, and the upper surface is black with the color nozzle opening row of the nozzle plate of the recording head. A capping device for an ink jet recording head, which has a partitioning part integrally formed with the cap member main body so as to come into contact with a boundary with the nozzle opening row for use. 2. The capping device for an ink jet recording head according to claim 1, wherein the partition portion is formed at a boundary portion of each nozzle opening row.