JPH0872265A - Ink jet device - Google Patents

Abstract

(57) [Abstract] [Purpose] To suck ink in the head without leaving ink on the nozzle surface. [Structure] After the suction of the ink in the head 2 by the pump is completed, the cap rubber is separated from the head 2 at a speed of 3 mm / s by the cap drive motor while the pump is being driven. At this time, the excess ink 31 remains between the nozzle 27 and the cap rubber 10. Subsequent driving of the pump separates the excess ink 31 into the nozzle 27 side and the cap rubber 10 side, and becomes a meniscus 32 protruding from the nozzle 27. Ink 30 drops down into the nozzle 27 of the meniscus 32. After such suction operation, no excess ink remains on the surface of the nozzle plate 26.

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, a head member and a cap member for moving the head member and the cap member relative to each other. The present invention relates to an ink ejecting apparatus having a moving unit that makes contact with and a detachment from a head, and a suction unit that is connected to the cap member and that generates a negative pressure in the cap member.

[0002]

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

A head 135 for ejecting ink from a nozzle (not shown) is mounted on a carriage 134.
The carriage 134 is moved along the platen 131 by a driving source (not shown). And platen 13
The carriage 1 is placed on the printing paper 132 conveyed onto the carriage 1.
Ink is ejected from the head 135 in accordance with the movement of 34, and image data is printed. Ink recovery means 136 (suction means) is provided near the home position HP of the carriage 134 (on the left side of the platen 131 in FIG. 5). The ink recovery unit 136 is driven forward and backward by a moving unit (not shown) with respect to the head 135, and caps the nozzle surface of the head 135 at the forward position to seal the nozzle surface.
7 and a pump 138 for sucking the ink in the head 135 from the nozzles through the capping means 137 by driving by a driving means (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 contact the nozzle surface of the head 135. Next, the pump 138 is driven by the driving unit to perform the 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 is a problem that the print quality is deteriorated due to an unstable ink ejection direction or defective ink ejection.

To cope with this, after the suction operation, the ink on the nozzle surface can be removed by wiping off the nozzle surface of the head 135 with a flexible blade formed of a plastic material or a rubber material. It is considered. However, the ink removed from the nozzle surface adheres to the blade after wiping the nozzle surface, and when the nozzle surface is then wiped off, the nozzle surface is wiped off again by using the blade to which the ink has adhered. Therefore, when the nozzle surface is wiped off, there is a problem in that the ink dried and thickened by the blade adheres to the nozzle surface to form a thin film of the thickened ink, which makes it impossible to jet well. Further, the nozzle surface is formed with a water-repellent film for preventing ink from adhering to the periphery of the nozzle. However, when dry ink is adhered to the blade, the water-repellent film is formed when the nozzle surface is wiped off. It may deteriorate. When the water-repellent film is deteriorated, the ink is likely to remain around the nozzles, the ink ejection direction becomes unstable, and the printing quality deteriorates.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an ink ejecting apparatus capable of sucking the ink in the head without leaving the ink on the nozzle surface. To do.

[0008]

To achieve this object, in a first aspect of the present invention, a head for ejecting ink from a nozzle, a cap member capable of covering the nozzle, the head and the cap member are provided. Relative to
An ink ejecting apparatus comprising: a moving unit that contacts and separates the cap member and the head; and a suction unit that is connected to the cap member and generates a negative pressure in the cap member. While operating to generate a negative pressure in the cap member, the moving means is operated to move the cap member from the head by 5 mm / s.
It is provided with control means for separating at the following speeds.

According to a second aspect of the present invention, the moving means moves the cap surface of the cap member relatively parallel to the nozzle surface of the head.

According to a third aspect of the present invention, the moving means moves the cap member.

[0011]

In the ink jet apparatus of the present invention having the above structure, the control means operates the moving means while operating the suction means to generate a negative pressure in the cap member. 5 mm / from the head
By separating at a speed of s or less, the ink on the nozzle surface of the head is sucked into the cap member when the cap member is opened, and no ink remains on the nozzle surface.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An 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
Is rotatably provided in the direction of arrow A in FIG. 1, and the guide shaft 4 is provided along the platen 16 thereof. A carriage 3 is slidably attached to the guide shaft 4, and a belt 7 is attached to the carriage 3. The belt 7 is wound around the idle pulley 8 and the drive pulley 6. The drive pulley 6 is rotated by the carriage drive motor 5, and the rotation of the drive pulley 6 moves the carriage 3 along the guide shaft 4 via the belt 7 in the direction of arrow B in FIG. The head 2 is mounted on the carriage 3 so as to face the platen 16.

As shown in FIG. 3, the head 2 has a plurality of ink flow paths 25 and a nozzle plate 26 having nozzles 27 corresponding to the ink flow paths 25. Then, the ink 30 is supplied from the ink supply source (not shown) to the head 2 via the supply tube 29 and the connecting member 28, and the ink 30 is filled in the ink flow path 25. The head 2 includes a shear mode type disclosed in Japanese Patent Laid-Open No. 2-150355, a Kaiser type disclosed in Japanese Patent Publication No. 53-12138, and a thermal jet disclosed in Japanese Patent Publication No. 61-59914. A mold or the like is used. The water repellent film is formed on the nozzle surface of the head 2.

As shown in FIG. 1, the print paper 17 inserted into the housing 21 from the rear of the printer 1 in the direction of arrow C in FIG. It is discharged from the housing 21. When the printing paper 17 is conveyed to the platen 16,
The head 2 ejects ink droplets as the carriage 3 moves, whereby desired data is printed on the printing paper 17.

A cap 9 is provided at a non-printing position of the head 2 on the left side of the platen 16 in FIG. 1, and a cap rubber 10 for closely contacting the head 2 is attached to the cap 9.
Is attached. And the cap 9 is the head 2
In contrast, it is attached 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 attached.
Is rotated in the direction of arrow F, the cap 9 is moved via the rack 19 and the expedient cap rubber 10 is brought into close contact with the head 2. A connecting tube 12 is attached to the cap 9. A pump 11 as a suction means is connected to the connecting 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 is composed of the cap 9 and the cap rubber 10, and the moving means is composed of the cap drive motor 18, the pinion 22 and the rack 19.

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

Next, the operation of the printer 1 by the control unit 40 will be described with reference to FIGS. As shown in Figure 1,
The printing paper 17 moves in the direction of arrow C to the housing 2 of the printer 1.
1 is inserted into the platen 16 and conveyed to the platen 16. And
The head 2 attached to the carriage 3 that is moved in the direction of arrow B by the carriage drive motor 5 ejects ink droplets according to the input data when the head 2 is sent to the position of the print sheet 17, and the print sheet 17 is ejected. To form an image.

Therefore, when the head 2 prints a fixed amount or 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 the non-printing position on the left side of the platen 16 in FIG. Next, the cap drive 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).

After that, 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 (state of FIG. 3B).

Subsequently, the pump 11 is driven, that is, the cap rubber 10, the cap 9 and the connecting tube 1.
Cap drive motor 18 while the pressure inside 2 is reduced
Is driven to move the cap 9, and the cap rubber 10
Moves away from the head 2 at a speed of 3 mm / s (Fig. 3 (c)).
State). At this time, the excess ink 31 remains between the nozzle 27 and the cap rubber 10.

By the subsequent drive of the pump 11, the excess ink 31 is separated into the nozzle 27 side and the cap rubber 10 side, and becomes a meniscus 32 protruding from the nozzle 27 (state of FIG. 3D).

The meniscus 32 is pulled down into the nozzle 27, and the ink in the cap rubber 10, the cap 9 and the connecting tube 12 is driven by the pump 11 to drive the ink.
It is discharged to the adsorbent 15 in the waste ink tank 14 via the discharge tube 13 (state of FIG. 3E). At this time, no excess ink remains on the surface of the nozzle plate 26.

In the printer 1 thus constructed, after the suction operation of the ink 30 from the head 2, the cap 9 is removed from the head 2 at a slow speed of 3 mm / s while performing the suction operation by the pump 11. Since they are separated, the surplus ink 31 protruding from the nozzle 27 is sucked into the cap 9. For this reason, there is no problem in the related art due to the ink remaining on the nozzle surface. Therefore, it is not necessary to perform the ink removal operation on the nozzle surface after suction, which is conventionally necessary, and the water-repellent film on the nozzle surface is less likely to deteriorate.

Here, it is examined whether ink remains on the nozzle surface when the speed of the cap 9 moving away from the head 2 is changed, and the result is shown in FIG. When the moving speed of the cap 9 was 5 mm / s or less, ink did not remain on the nozzle surface, and when the moving speed of the cap 9 was 6 mm / s and 7 mm / s, ink partially remained on the nozzle surface. From this result, the moving speed of the cap 9 may be set to 5 mm / s or less.

The present invention is not limited to the embodiment described in detail above. For example, in this embodiment, the cap 9 was moved in parallel to the head 2 (direction of arrow E).
The cap 9 may be separated from the head 2 by turning. In this case, the side of the cap 9 on which the speed of moving away from the head 2 is fast is set to move away from the head 2 at a speed of 5 mm / s or less.

Although the cap 9 is separated from the head 2 by the drive of the cap drive motor 18 in this embodiment, the head 2 may be moved to separate from the cap 9.

[0028]

As is apparent from the above description,
According to the ink ejecting apparatus of the present invention, the control means operates the moving means to operate the suction means to generate a negative pressure in the cap member and move the cap member from the head by 5 mm / Since the ink is removed at a speed of s or less, the ink on the nozzle surface of the head is sucked into the cap member when the cap member is opened, and the ink does not remain on the nozzle surface. Therefore, the ink can be ejected well, and the print quality is good.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an inkjet printer according to an 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 diagram showing a speed of leaving the head of the cap of the embodiment and a state of ink remaining on a nozzle surface.

FIG. 5 is an explanatory diagram showing a configuration of a conventional ink ejecting apparatus.

[Explanation of symbols]

 1 Printer 2 Head 3 Carriage 5 Carriage Drive Motor 9 Cap 10 Cap Rubber 11 Pump 18 Cap Drive Motor 19 Rack 22 Pinion 27 Nozzle 40 Control Unit

Claims (3)

[Claims] 1. A head for ejecting ink from a nozzle,
A cap member capable of covering the nozzle, a moving unit that relatively moves the head and the cap member to bring the cap member and the head into contact with each other, and withdrawal from the head, and are connected to the cap member. An ink ejecting apparatus having suction means for generating a negative pressure in the cap member, wherein the moving means is operated to operate the moving means while generating a negative pressure in the cap member. An ink ejecting apparatus comprising control means for separating the head from the head at a speed of 5 mm / s or less. 2. The ink ejecting apparatus according to claim 1, wherein the moving unit moves the cap surface of the cap member relatively parallel to the nozzle surface of the head. 3. The ink ejecting apparatus according to claim 1, wherein the moving unit moves the cap member.