JP3249685B2 - Ink jet device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head for ejecting ink from a nozzle, a cap member capable of covering the nozzle, and a relative movement of the head and the cap member. First moving means for performing contact and detachment with the head, and connected to the cap member,
The present invention relates to an ink ejecting apparatus having a suction means for generating a negative pressure in the cap member.

[0002]

2. Description of the Related Art A conventional ink ejecting apparatus having a suction means is disclosed in Japanese Patent Application Laid-Open No. Sho 62-77940, and its schematic structure will be described below with reference to FIG.

A head 135 for ejecting ink from nozzles (not shown) is mounted on a carriage 134,
The carriage 134 is moved along the platen 131 by a driving source (not shown). And the platen 13
1 on the printing paper 132 conveyed on the carriage 1
The ink is ejected from the head 135 along with the movement of the head 34 to print the image data. In the vicinity of the home position HP of the carriage 134 (left side of the platen 131 in FIG. 6), an ink recovery unit 136 # (suction unit) is provided. The ink recovery means 136 is driven forward and backward by a moving means (not shown) with respect to the head 135, and the capping means 1 for closing the nozzle surface of the head 135 at the forward position.
37, and a pump 138 for sucking the ink in the head 135 from the nozzles through the capping unit 137 by driving by a driving unit (not shown).

After printing the image data, the carriage 1
34 is moved to the home position HP, and the capping means 137 is moved forward by the moving means to come into contact with the nozzle surface of the head 135. Next, the pump 138 is driven by the driving means to perform an ink recovery operation (ink suction operation). When the ink suction operation is completed, the capping means 137 is retracted.

[0005]

However, ink may remain on the nozzle surface of the head 135 after the suction operation. And if ink remains around the nozzle,
There has been a problem that the ink jetting direction becomes unstable or the ink jetting becomes defective, thereby deteriorating the print quality.

To cope with this, after the suction operation, the ink on the nozzle surface of the head 135 is removed by wiping the nozzle surface of the head 135 with a flexible blade made of a plastic material or a rubber material. It is considered. However, the ink removed from the nozzle surface adheres to the blade after the nozzle surface has been wiped, and when the nozzle surface is next wiped, the nozzle surface to which the ink has adhered is used again to wipe the nozzle surface. Therefore, when the nozzle surface is wiped off, there is a problem that the ink dried and thickened by the blade adheres to the nozzle surface to form a thickened ink film, which makes it impossible to jet well. Was. Further, on the nozzle surface, a water-repellent film for preventing ink from adhering around the nozzle is formed. There is a risk of deterioration. When the water-repellent film deteriorates, ink tends to remain around the nozzles, the ink ejection direction becomes unstable, and the print quality deteriorates.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide an ink ejecting apparatus capable of sucking ink in a head without leaving ink around a nozzle. I do.

[0008]

In order to achieve this object, according to the first aspect of the present invention, there is provided a head for ejecting ink from a nozzle opened on a nozzle surface, a cap member capable of covering the nozzle, and the head. And a first moving means for relatively moving the cap member and bringing the cap member and the nozzle surface into and out of contact with each other, and connected to the cap member to apply a negative pressure to the cap member. An ink ejecting device having a suction unit for generating the ink, wherein the head and the cap member are opened by opening the cap member while maintaining a distance between the nozzle surface and the cap member .
A second moving unit that relatively moves in a direction in which the unit is shifted to a position not facing the nozzle; and, by operating the suction unit, sucking ink from the nozzle of the head via the cap member, and then performing the first Activating the moving means, operating the second moving means in a state where the sucked ink is connected between the cap and the head by separating the cap member and the nozzle surface at a distance of 2 mm or less. Opening the head and the cap to the opening of the cap member
Control means for relatively moving the unit in a direction in which the unit does not face the nozzle and sucking ink on the nozzle surface toward the cap member.

The suction means reduces the pressure inside the cap member by 0.2 to 0.3 kg / cm ² below the pressure outside the cap member.

[0010]

In the ink jetting apparatus of the present invention having the above structure, the control means sucks ink from the nozzles of the head through the cap member by operating the suction means, and then controls the first moving means. Is operated to separate the cap and the head at a distance of 2 mm or less, and in a state where the sucked ink is connected between the cap and the head, the second moving means is operated to move the cap member. The ink on the nozzle surface is moved to a position away from the nozzle by moving the opening relatively to a position not facing the nozzle , so that the suction operation is performed without ink remaining around the nozzle. .

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

First, the configuration of this embodiment will be described with reference to FIG. In the housing 21 of the printer 1, the platen 16
Are provided rotatably in the direction of arrow A in FIG. 1, and the guide shaft 4 is provided along the platen 16. A carriage 3 is slidably mounted on the guide shaft 4, and a belt 7 is mounted on the carriage 3. The belt 7 is hung on the idle pulley 8 and the drive pulley 6. The drive pulley 6 is rotated by a carriage drive motor 5, and the carriage 3 is moved in the direction of arrow B in FIG. 1 along the guide shaft 4 via the belt 7 by the rotation of the drive pulley 6. The head 2 is mounted on the carriage 3 so as to face the platen 16. The second moving means includes a carriage driving motor 5, a driving pulley 6, a belt 7, and the carriage 3.

As shown in FIG. 3, the head 2 has a plurality of ink channels 25 and a nozzle plate 26 in which nozzles 27 corresponding to the ink channels 25 are formed. The water-repellent film is formed on the ink jet side of the nozzle plate 26. Then, the ink 30 is supplied to the head 2 from a not-shown ink supply source via the supply tube 29 and the connecting member 28, and is filled in the ink flow path 25. This head 2 is disclosed in Japanese Patent Application Laid-Open No. 2-15035.
No. 5 discloses a shear mode type disclosed in Japanese Patent Publication No.
A Kaiser type disclosed in JP-A-12138 and a thermal jet type disclosed in JP-B-61-59914 are used.

As shown in FIG. 1, the printing paper 17 inserted into the housing 21 in the direction of arrow C in FIG. 1 from the rear of the printer 1 is conveyed along the platen 16 in the direction of arrow D, and It is discharged from the housing 21. When the printing paper 17 is transported to the platen 16,
Desired data is printed on the printing paper 17 by the head 2 ejecting ink droplets with the movement of the carriage 3.

A cap 9 is provided at a non-printing position of the head 2 on the left side of the platen 16 in FIG.
Is attached. And the cap 9 is the head 2
Are mounted so as to be movable in the direction of arrow E in FIG. A rack 19 is attached to the cap 9, and a pinion 22 attached to the cap drive motor 18 is provided.
The cap 9 is moved via the rack 19 by the rotation in the direction of arrow F, and the cap rubber 10 is brought into close contact with the head 2 for convenience. A connection tube 12 is attached to the cap 9. A pump 11 as suction means is connected to the connection tube 12 and a discharge tube 13
Is connected to the waste ink tank 14 in which the adsorbent 15 is stored. The cap member includes a cap 9 and a cap rubber 10, and the first moving unit includes a cap driving motor 18, a pinion 22, and a rack 19.

FIG. 2 is a block diagram showing the configuration of a control system. The control unit 40 of the printer 1 (FIG. 1) responds to a print command from a host computer 41 to control a head drive circuit 42,
A drive command is sent to the carriage drive circuit 43, the cap drive circuit 44, the paper feed circuit 45, and the pump drive circuit 46, and the head 2, the carriage drive motor 5, the cap drive motor 18, the paper feed mechanism (not shown), and the pump 11 are sent. Drive control.

Next, the operation of the printer 1 by the control unit 40 will be described with reference to FIGS.

As shown in FIG. 1, the printing paper 17 is
Is inserted into the housing 21 of the printer 1 in the direction of FIG. The head 2 attached to the carriage 3 moved in the direction of arrow B by the carriage drive motor 5 ejects ink droplets according to the input data when sent to the position of the printing paper 17, 17, an image is formed.

Therefore, when the head 2 prints a predetermined amount or when the user performs maintenance operations as necessary, such as defective ink ejection, the maintenance of the head 2 is performed. At times, the head 2 is moved to a non-printing position on the left side of the platen 16 in FIG. Next, the cap driving motor 18 is driven, the cap 9 approaches the head 2, the cap rubber 10 comes into close contact with the head 2, and the vicinity of the nozzle 27 of the head 2 is covered (the state of FIG. 3A).

Thereafter, a negative pressure is generated in the space between the cap 9 and the head 2 by driving the pump 11, and the ink in the head 2 is sucked (the state shown in FIG. 3B). The pump 1 is set so that the pressure inside the cap 9 at the time of sucking the ink is 0.2 to 0.3 kg / cm ² lower than the pressure outside the cap 9.
1 is driven.

Then, the driving of the pump 11 is stopped. Subsequently, the cap driving motor 18 is driven to move the cap 9, and the distance L between the cap rubber 10 and the nozzle plate 26 on the front surface of the head 2 becomes 0.2 mm. (FIG. 3 (c)). At this time, the surplus ink 31 remains between the nozzle 27 and the cap rubber 10.

With the distance L between the cap rubber 10 and the nozzle plate 26 kept at 0.2 mm, the carriage drive motor 5 is driven to move the carriage 3 via the drive pulley 6 and the belt 7. Due to this movement, the opening of the cap rubber 10 is shifted to a position not facing the nozzle 27 (the state of FIG. 4A). At this time, the surplus ink 3
1 is a nozzle plate 2 with the movement of the cap 9.
It is moved to a position away from the nozzle 27 on the six surfaces, and is separated into a portion 33 connecting the nozzle plate 26 and the cap rubber 10 and a meniscus 32 protruding from the nozzle 27.

Thereafter, a portion 33 connecting the cap rubber 10 of the surplus ink 31 and the surface of the nozzle plate 26 is formed.
Is separated into the nozzle plate 26 surface side and the cap 9 side by the tension of the ink in the cap rubber 10, and the remaining ink 34 remains on the nozzle plate 26 surface side (the state of FIG. 4B).

The meniscus 32 is connected to the nozzle 27
And the cap 9 is further separated from the head 2,
The ink in the cap rubber 10, the cap 9, and the connection tube 12 is supplied to the discharge tube 1 by driving the pump 11.
The ink is discharged to the adsorbent 15 in the waste ink tank 14 through the nozzle 3 (the state shown in FIG. 4C). At this time, nozzle plate 2
No surplus ink remains around the nozzle 27 of No. 6.

In the printer 1 configured as described above, after the suction operation of the ink 30 from the head 2 is performed, the distance L between the cap rubber 10 and the surface of the nozzle plate 26 is set to 0.1.
2 mm, the carriage 3 is moved in that state, and the opening of the cap rubber 10 and the nozzle 27 are moved to a position where they do not face each other. As a result, it is moved to a position away from the nozzle 27 on the surface of the nozzle plate 26, and is separated into a portion 33 connecting the nozzle plate 26 and the cap rubber 10 and a meniscus 32 protruding from the nozzle 27. A portion 33 connecting the nozzle plate 10 and the surface of the nozzle plate 26 has a cap rubber 10
The ink is separated into the nozzle plate 26 surface side and the cap 9 side by the tension of the ink inside, and the remaining ink 34 remains on the nozzle plate 26 surface side. That is, no ink remains around the nozzles 27 of the nozzle plate 26. For this reason, the conventional problem caused by the ink remaining on the nozzle surface does not occur. Therefore, there is no need to perform the ink removal operation on the nozzle surface after suction, which is conventionally required, and the water-repellent film on the nozzle surface is less likely to deteriorate.

Here, when the distance L between the cap rubber 10 and the nozzle plate 26 is changed and the pump 11 is driven, it is checked whether or not ink remains on the nozzle surface. The result is shown in FIG. When the ink (high viscosity) is connected between the cap rubber 10 and the nozzle plate 26, that is, when the distance L is 2 mm or less, no ink remains on the nozzle surface, and the distance L is 2.5 mm, 3.0 mm, 3 mm. At 0.5 mm, ink partially remained around the nozzle 27. From this result, the distance L between the cap rubber 10 and the nozzle plate 26 was set to 2 m
The carriage 3 may be moved in a state where the distance is equal to or less than m.

The present invention is not limited to the embodiment described in detail above. For example, in the present embodiment, the cap 9 is moved parallel to the head 2 (in the direction of arrow E).
The cap 9 may be separated from the head 2 by turning. In this case, the carriage 3 is moved with the distance L of the cap rubber 10 away from the nozzle plate 26 being 2 mm or less.

In the present embodiment, the cap 9 is separated from the head 2 by driving the cap drive motor 18, but the head 2 may be moved to separate from the cap 9.

In the present embodiment, the carriage 3 is moved after the cap 9 is detached from the head 2, but the carriage 3 is moved.
The cap 9 may be moved without moving the carriage 3 and keeping the distance L between the cap rubber 10 and the nozzle plate 26.

In this embodiment, the pump 11 is driven in the state shown in FIG. 4C to discharge the sucked ink to the waste ink tank 14. However, in the state shown in FIG.
1 may be driven to discharge the sucked ink to the waste ink tank 14. By doing so, the nozzle plate 2
6 can be reduced.

[0031]

As is apparent from the above description,
According to the ink ejecting apparatus of the present invention, after the control means sucks ink from the nozzles of the head via the cap member by the operation of the suction means, the control means activates the first moving means to thereby form the cap. And the head 2m
m and the cap member is opened by operating the second moving means in a state where the sucked ink is connected between the cap and the head between the cap and the head at a distance of m or less. Part does not face the nozzle
Since relatively moving in a direction deviated location, the ink on the nozzle surface is moved to a position away from the nozzle, it is possible to perform the suction operation without ink remains around the nozzle. For this reason, the water repellent film on the nozzle surface is hardly deteriorated, and the ink can be ejected satisfactorily, and the printing quality is good.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an ink jet printer according to one embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a control system of the embodiment.

FIG. 3 is an explanatory diagram showing a suction operation of the embodiment.

FIG. 4 is an explanatory view showing the suction operation of the embodiment following FIG. 3;

FIG. 5 is an explanatory diagram showing a distance between a suction unit of the embodiment and a nozzle surface of a head and a state of ink remaining on the nozzle surface.

FIG. 6 is an explanatory diagram showing a configuration of a conventional ink ejecting apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer 2 Head 3 Carriage 5 Carriage drive motor 6 Drive pulley 7 Belt 9 Cap 10 Cap rubber 11 Pump 18 Cap drive motor 19 Rack 22 Pinion 27 Nozzle 40 Control part

Claims (2)

(57) [Claims] 1. A head for ejecting ink from a nozzle opened on a nozzle surface, a cap member capable of covering the nozzle, and the head and the cap member being relatively moved to form the cap member and the nozzle. An ink ejecting apparatus comprising: a first moving unit that contacts and separates from a surface; and a suction unit that is connected to the cap member and generates a negative pressure in the cap member. A second moving means for relatively moving the head and the cap member in a direction in which the opening of the cap member is shifted to a position not facing the nozzle while maintaining a distance from the head, and operation of the suction means By suctioning ink from the nozzles of the head via the cap member, the first moving means is operated to allow the cap member and the nozzle surface In a state where the sucked ink is connected between the cap and the head at a distance of 2 mm or less, the second moving means is operated to open the head and the cap so that the opening of the cap member is Relatively moving in a direction to shift to a position not facing the nozzle,
A control unit for sucking the ink on the nozzle surface toward the cap member. 2. The suction means according to claim 1, wherein the pressure inside the cap member is 0.2 to 0.3 kg / cm ² from the pressure outside the cap member.
2. The ink ejecting apparatus according to claim 1, wherein said ink ejecting apparatus is set at a lower temperature.