JP3259502B2 - Ink jet recording device - Google Patents

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 for performing recording by discharging ink from a discharge port of a recording head, and more particularly to an ink jet recording apparatus for cleaning the discharge port of the recording head with a cleaning blade member.

[0002]

2. Description of the Related Art In a conventional ink jet apparatus, an ejection surface having a plurality of ejection ports for ejecting ink to a recording head is formed. When dust or paper debris adheres to the discharge surface, a means for wiping and cleaning with a cleaning blade is used.

On the other hand, in a color ink jet recording apparatus, recording is usually performed with inks of yellow (yellow), magenta (red), cyan (blue) and black (black), and a specific recording head is provided for each color. Is provided,
A plurality of cleaning blades are provided.

[0004]

In the above-mentioned conventional ink jet apparatus, a plurality of cleaning blades are provided corresponding to a plurality of recording heads for ejecting inks of different components. The state of the ink adhering to the ejection surface of the recording head is different. For this reason, it has been necessary to wipe the ejection surfaces of the plurality of recording heads with a cleaning blade in accordance with the most dirty state. For this reason, the ejection surface of the recording head having a relatively small stain is also wiped off in the same state, so that there is a problem that the deterioration of the ejection surface is accelerated and the image quality is deteriorated.

The present invention solves the above-mentioned conventional problems. By wiping the recording head with an appropriate cleaning blade for each recording head, it is possible to increase the number of unnecessary wiping operations without increasing the number of unnecessary wiping operations. It is an object of the present invention to provide an ink jet recording apparatus that suppresses surface deterioration and does not lower image quality.

[0006]

For this purpose, an ink jet recording apparatus according to the present invention comprises a plurality of recording heads for recording by discharging ink from discharge ports, and a recording head for each recording head.
An ink jet recording apparatus having a cleaning blade disposed and wiping a nozzle surface thereof , wherein each of the cleaning blades has a different rigidity. Also, the cleaning blade and the recording head
The amount of contact is varied .

[0007]

According to the present invention, in the case of an ink jet recording apparatus having a plurality of recording heads, the components of the ink to be ejected differ for each recording head, and the density and viscosity of the ink differ. Since the amount of ink is also different, the specifications of the cleaning blade are made different for each recording head, so that the image quality does not deteriorate over a long period of time.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an example of an ink jet recording apparatus to which the present invention is applied.

In FIG. 1, a carriage 2 is slidably mounted between two guide rails 1 and
Is connected to a carriage driving motor 4 via a timing belt 3. The carriage 2 has four inkjet cartridges 5 of cyan, magenta, yellow, and black mounted thereon. These ink cartridges are detachably mounted on the carriage 2 by the lock lever 6. On the lower surface of each ink jet cartridge 5, a recording head (20 in FIG. 2) having a large number of ink discharge nozzles is provided, and an ink tank 7 for supplying ink to the recording head is built in. The drive signal is transmitted by the signal cable 8.

A feed roll 9 and an exit roll 10 are disposed between the two guide rails 1 in parallel with the guide rail 1. The feed roll 9 and the exit roll 1
Reference numeral 0 is connected to a paper feed motor 14 via gears 11 and 12 and a belt 13. The recording on the recording paper 15 is
The recording head is driven while moving the carriage 2 from left to right of the recording paper 15 to perform recording for the head width, and the recording paper 15 is moved in the direction of the arrow by the head width in preparation for the next printing. I have. At a position facing the end of the guide rail 1, a maintenance unit 16 for cleaning the nozzle surface of the recording head and preventing the nozzle surface from drying is provided.

FIG. 2 is a sectional view of the maintenance unit 16 of FIG. 1, FIG. 3 is an assembled perspective view of the maintenance unit 16 of FIG. 1, and FIG. 4 is an enlarged sectional view showing a main part. In FIG. 2, only two recording heads are shown, and other recording heads are omitted.

The maintenance unit 16 has a cleaning device 17 and a capping device 19. The cleaning devices 17 are provided for cleaning the nozzle surfaces 21 of the recording heads 20 for discharging the respective color inks, and each of the recording heads 2 is placed on a vertically movable support base 22.
It is arranged adjacent to the capping device 19 that covers the nozzle surface 21 of No. 0.

In the cleaning device 17, a support bracket 23 having an L-shaped cross section is attached to a support base 22, and a plate-like cleaning blade 24 made of elastic rubber is sandwiched between the support bracket 23 and a holding plate 25. With the tip of the cleaning blade 24 fixed and disposed slightly protruding from the position of the nozzle surface 21 of the recording head 20, for example, the recording head 20 is moved from the position indicated by the solid line in FIG. The cleaning blade 24 is configured to wipe off the nozzle surface 21 of the recording head 20 for cleaning.

At both ends in the longitudinal direction of the support table 22, leg pieces 27 extending downward are formed, and one inner guide pin 28 is protruded from the inner surface of the leg piece 27. 27 have two outer guide pins 29
Is protruding. The support base 22 is provided in a housing 30 opened upward. A rotary shaft 31 driven by a drive motor 32 is rotatably supported by the housing 30, and a substantially heart-shaped eccentric cam 33 is fixed to both ends of the rotary shaft 31. A substantially heart-shaped guide groove 3 is provided on the housing 30 side of the eccentric cam 33.
The inner guide pin 28 is slidably engaged with the guide groove 34, and a guide groove 35 extending vertically is formed on the inner side surface of the housing 30. The two outer guide pins 29 are slidably engaged in the vertical direction.

Therefore, the support base 22 is raised and lowered to an appropriate position by an engagement position between the eccentric cam 33 and the inner guide pin 28 according to the rotation position of the rotary shaft 31, and the cleaning blade 24 of the cleaning device 17 It is moved between a cleaning position (a position slightly protruding from the nozzle surface 21 of the recording head 20) and a retracted position (a position not in contact with the nozzle surface 21 of the recording head 20), and the capping device 19 is moved to the capping position ( The recording head 20 can be moved between a position where the nozzle surface 21 is sealed and a retracted position (a position where the nozzle surface 21 is not in contact with the nozzle surface 21 of the recording head 20).

The capping device 19 has an elastic cap 36 that covers the nozzle surface 21 of the recording head 20 during non-printing. The elastic cap 36 is attached to the support base 22 via a cap holder 37. .
The cap holder 37 has a positioning boss 38 at a lower portion thereof, and the positioning boss 38 is inserted into the support table 22 in a vertically movable manner while being prevented from rotating by a positioning hole 39 opened in the support table 22. And is elastically supported by a compression spring 42 interposed between the retaining ring 41 and the retaining ring 41. A suction passage 43 is formed inside the cap holder 37 from the bottom of the cap 36, and the suction passage 43 is connected to a suction pump 44.

Next, an embodiment of the ink jet recording apparatus of the present invention will be described with reference to FIGS. FIG.
Shows an embodiment of the inkjet recording apparatus of the present invention,
FIG. 6 is a diagram showing parameters for varying the rigidity of the cleaning blade, and FIG. 6 is a diagram showing the evaluation results of the cleaning performance by the cleaning blade.

In the case of a color ink jet recording apparatus having a plurality of recording heads, the components of the ink ejected from each recording head 20 are different. Therefore, the ink concentration and the viscosity are different, so that the nozzle surface 21 of the recording head 20
The amount of ink adhering to the ink also differs. As a result, it is necessary to make the specifications of the cleaning blade 24 different for each recording head.

FIG. 6 shows the evaluation results of the cleaning performance of the cleaning blade 24 using a black ink having a relatively high density and viscosity and a yellow ink having a low density and viscosity compared to the black ink. The vertical axis of the graph indicates the amount of ink adhered to the nozzle surface 21 of the recording head 20, and the horizontal axis indicates the number of wiping operations performed by the cleaning blade 24. FIG. 6A shows the evaluation result with the black ink, and FIG. 6B shows the evaluation result with the yellow ink.

According to the evaluation results, the amount of ink adhering to the nozzle surface 21 of the recording head 20 is smaller in the yellow ink than in the black ink, and the yellow ink is wiped off with a small number of wipings. From this result, it is necessary to use a cleaning blade 24 having a different rigidity for each recording head. For a black ink, a cleaning blade having a high rigidity is used, and for a yellow ink, a cleaning blade having a low rigidity is used. The same level of cleaning performance can be achieved with the number of wiping operations, and it is possible to suppress an unnecessary increase in the number of wiping operations.

As means for varying the rigidity of the cleaning blade 24, as shown in FIG. 5, means for varying the material hardness of the cleaning blade 24, means for varying the plate thickness d of the cleaning blade 24, width of the cleaning blade 24, k, means for varying the length s of the elastically deformable area of the cleaning blade 24, and the amount m of the cleaning blade 24 in contact with the recording head 20 (the cleaning blade tip 24
There is a means for making the distance between a and the nozzle surface 21 different, and it has been found that an effective cleaning effect can be obtained by combining these means.

[0022]

As is apparent from the above description, according to the present invention, the ink jet recording which suppresses the deterioration of the nozzle surface of the recording head without increasing the number of unnecessary wipings and which does not deteriorate the image quality. An apparatus can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating an example of an inkjet recording apparatus to which the present invention is applied.

FIG. 2 is a cross-sectional view of the maintenance unit of FIG.

FIG. 3 is an assembly perspective view of the maintenance unit of FIG. 1;

FIG. 4 is an enlarged sectional view showing a main part of FIG. 2;

FIG. 5 is a view showing one embodiment of the ink jet recording apparatus of the present invention and showing parameters for varying the rigidity of the cleaning blade.

FIG. 6 is a diagram showing the evaluation results of the cleaning performance by a cleaning blade.

[Explanation of symbols]

Reference numeral 20: recording head, 21: nozzle surface, 24: cleaning blade d: plate thickness, k: width, s: length of elastically deformable area m: amount of contact with the recording head

Claims (8)

(57) [Claims] A plurality of printheads for performing printing by discharging ink from discharge ports, and a plurality of printheads provided for each printhead.
In the ink jet recording apparatus having a cleaning blade pay wiped the nozzle surface, the ink jet recording apparatus characterized by having different said rigidity of the cleaning blade. 2. A cleaning blade for wiping a nozzle surface of a recording head for discharging ink having a higher density than ink having a lower density has a higher rigidity.
3. The ink jet recording apparatus according to claim 1. 3. The rigidity of a cleaning blade for wiping a nozzle surface of a recording head for discharging ink having a higher viscosity than ink having a low viscosity is increased.
3. The ink jet recording apparatus according to claim 1. 4. An ink jet recording apparatus according to claim 1, wherein the rigidity is varied by varying the thickness of the cleaning blade. 5. The ink jet recording apparatus according to claim 1, wherein the rigidity is varied by varying the material hardness of the cleaning blade. 6. The cleaning blade according to claim 1, wherein the cleaning blade has a different width so as to have a different rigidity.
An ink jet recording apparatus according to claim 5. 7. The ink jet according to claim 1, wherein the rigidity is varied by varying the length of the elastically deformable region of the cleaning blade. Recording device. 8. Recording is performed by discharging ink from discharge ports.
A plurality of print heads, and
Cleaning blade for wiping the nozzle surface of
In the ink jet recording apparatus, the cleaning
Make the amount of contact between the blade and the recording head different
Characteristic inkjet recording device.