JP2004299299A - Wiping device for liquid ejection head, and liquid ejection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wiping device for a liquid ejection head, which can smoothly wipe liquid on the liquid ejection head even if a nozzle formation surface of the liquid ejection head has rugged portions. <P>SOLUTION: According to the structure of the wiping device, a blade member 21 has a distal end portion 21a inclusive of a tip on a straight line, to be abutted on the nozzle formation surface, and a proximal end portion 21b fixed into a holder member 22. The holder member 22 includes a backrest portion 22c which bears the blade member 21 having undergone deflection during sliding on the nozzle formation surface, on a deflecting side. The backrest portion 22c has a predetermined height distribution, i.e. the height of the backrest portion 22c is variable along a width direction of the blade member 21, and therefore a free length of the blade member 21, i.e. a length that can be deflected, has a predetermined length distribution along the width direction of the blade member 21. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wiping device for wiping a nozzle forming surface of a liquid ejecting head that ejects droplets from a nozzle opening toward a target, and a liquid ejecting device including the wiping device.
[0002]
[Prior art]
As a typical example of a conventional liquid ejecting apparatus, there is an ink jet recording apparatus provided with an ink jet recording head for image recording. Other liquid ejecting apparatuses include, for example, an apparatus provided with a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, an electrode material (conductive paste) used for forming an electrode such as an organic EL display and an FED (surface emitting display). Examples of the apparatus include an apparatus equipped with an ejection head, an apparatus equipped with a biological organic substance ejection head used for biochip production, and an apparatus equipped with a sample ejection head as a precision pipette.
[0003]
An ink jet recording apparatus, which is a typical example of a liquid ejecting apparatus, has relatively low noise at the time of printing and can form small dots at a high density, and thus is used in many printings including color printing in recent years. .
[0004]
Such an ink jet recording apparatus is generally equipped with a recording head (liquid ejecting head) mounted on a carriage and reciprocating in the width direction (head scanning direction) of a recording medium such as recording paper, and a recording medium in a head scanning direction. Feeding means for moving in a direction (medium feeding direction) orthogonal to the above.
[0005]
In this ink jet recording apparatus, printing is performed by discharging ink droplets (droplets) from a recording head onto a recording medium in accordance with print data. By making the recording head mounted on the carriage capable of discharging, for example, black, yellow, cyan, and magenta inks, not only text printing with black ink but also the discharge ratio of each ink can be reduced. By changing, full-color printing is possible.
[0006]
The above-described recording head performs printing by discharging ink pressurized in the pressure chamber from the nozzle opening toward the recording medium as an ink droplet, for example, an increase in ink viscosity due to evaporation of a solvent from the nozzle opening, In addition, there is a problem that printing failure occurs due to solidification of the ink, adhesion of dust, and mixing of air bubbles.
[0007]
Therefore, when the nozzle opening of the recording head is clogged or the ink cartridge is replaced, the nozzle forming surface of the recording head is sealed with the cap member, and the negative pressure from the suction pump (tube pump) is applied. Cleaning that performs a cleaning operation (suction operation) that eliminates clogging due to ink solidification at the nozzle opening and the like and ink ejection failure due to air bubbles entering the ink supply path by suctioning and discharging ink from the nozzle opening by pressure. The apparatus is generally provided in an ink jet recording apparatus.
[0008]
Further, the conventional ink jet recording apparatus is provided with a wiping apparatus having a blade member made of an elastic material such as rubber for wiping a nozzle forming surface of a recording head after a cleaning operation. Then, after forcibly sucking and discharging the ink from the nozzle openings of the recording head, the recording head is moved while the blade member is in contact with the nozzle forming surface of the recording head. Can be dispelled.
[0009]
FIG. 7 shows a conventional wiping device. The wiping device 50 includes a rectangular flat blade member 51 made of an elastic material such as rubber, and a holder member 52 that holds the blade member 51. I have. The blade member 51 includes a distal end portion 51a that comes into contact with the nozzle forming surface of the recording head, and a proximal end portion 51b that is inserted and fixed inside the holder member 52.
[0010]
The holder member 52 includes a main body portion 52a including a space for receiving the base end portion 51b of the blade member 51, and a lever portion 52b formed integrally with the main body portion 52a. The lever 52b is incorporated in the recording apparatus so as to be rotatable together with the main body 52a about the rotation axis O shown in FIG. When performing the wiping operation, the blade member 51 that has been waiting at a position deviating from the movement locus of the recording head is arranged around the movement locus of the recording head by rotating the blade member 51 around the rotation axis O. .
[0011]
FIG. 8 shows a state where the nozzle forming surface 12a of the recording head 12 is wiped by the conventional wiping device 50 shown in FIG. As described above, the wiping operation is performed by moving the recording head 12 with the blade member 51 of the wiping device 50 pressed against the nozzle forming surface 12a of the recording head 12.
[0012]
[Patent Document 1]
JP 2002-307700 A
[Problems to be solved by the invention]
As shown in FIG. 8, the recording head 12 is configured by fixing a nozzle plate 12b including a nozzle forming surface 12a to a head casing 12d by a head cover 12c. The peripheral portion of the nozzle forming surface 12a is covered with a head cover 12c. Due to the thickness of the head cover 12c, a step S extending in the moving direction (wiping direction) of the recording head 12 (and orthogonal to the step S). (A step portion extending in the direction of movement).
[0014]
Therefore, when the distal end portion 51a of the blade member 51 is pressed against the nozzle forming surface 12a, a gap is generated between the distal end portion 51a of the blade member 51 and the nozzle forming surface 12a in the step portion S. When the gap is formed in this manner, the ink is not wiped by the blade member 51 in that portion, so that the ink remains after the wiping operation. If the ink remaining after wiping is solidified, there is a possibility that sufficient adhesion may not be secured due to the presence of the solidified ink when the nozzle forming surface 12a is sealed by capping means during a cleaning operation.
[0015]
In consideration of the above-described problem, in order to enable the wiping device to sufficiently wipe the ink even at the stepped portion S generated between the head cover 12c and the nozzle forming surface 12a, for example, a blade member for the recording head 12 is used. A method of increasing the pressing force of 51 over the entire blade member 51 is conceivable.
[0016]
However, in this method, by repeatedly performing the wiping operation, there is a possibility that a process such as plating applied to the nozzle forming surface 12a in advance is destroyed. If the treatment such as plating on the surface of the nozzle forming surface 12a is destroyed, the water repellency of the surface is impaired, and normal printing may not be performed. In addition, there is a problem that the wear of the blade member 51 when sliding on the nozzle forming surface 12a is accelerated, and dust of the shaved blade material is generated, and the wiping function of the blade member 51 is impaired. Further, since the pressing force of the blade member 51 is strong, after wiping the nozzle forming surface 12a, the bent blade member 51 returns to the original state vigorously, and at this time, there is a problem that the ink scatters violently. .
[0017]
Further, as another method for sufficiently wiping the ink by the wiping device even at the stepped portion S, a method of devising the shape of the contact portion of the blade member according to the uneven shape on the nozzle forming surface 12a. Can be considered.
[0018]
However, in this method, an elastic material such as rubber, which is generally difficult to process, needs to be processed into a complicated shape that is not a simple shape (for example, a square shape), resulting in an increase in manufacturing cost. There is.
[0019]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has a liquid ejecting head capable of wiping liquid on the liquid ejecting head without hindrance even when unevenness exists on the nozzle forming surface side of the liquid ejecting head. It is an object to provide an apparatus and a liquid ejecting apparatus including the same.
[0020]
[Means for Solving the Problems]
In order to solve the above problem, the present invention is a wiping device for wiping a nozzle forming surface of a liquid ejecting head that ejects droplets from a nozzle opening toward a target, wherein the nozzle of the liquid ejecting head is A blade member made of an elastic material, which is in contact with a forming surface and slides on the nozzle forming surface by a relative movement with respect to the liquid ejecting head, and a holder member for holding the blade member; The member has a distal portion including a linear distal portion abutting on the nozzle forming surface, and a proximal portion fixed to the holder member, wherein the holder member includes the nozzle forming surface. A backrest for supporting the blade member bent at the time of sliding on the upper side in a bending direction side of the blade member, wherein the backrest is located at a position perpendicular to a moving direction of the liquid ejecting head. It has a predetermined height distribution in which the height changes along the width direction of the blade member, whereby the free length, which is the length of the bendable portion of the blade member, extends along the width direction of the blade member. And has a predetermined length distribution.
[0021]
Preferably, the predetermined height distribution of the backrest portion includes a portion that is raised corresponding to a step portion existing on the nozzle forming surface side.
[0022]
Preferably, a head cover is attached to an edge of the nozzle forming surface of the liquid ejecting head, and the predetermined height distribution of the backrest portion is formed on the nozzle forming surface side by the presence of the head cover. And a raised portion corresponding to the stepped portion.
[0023]
Preferably, the predetermined height distribution of the backrest portion includes a portion that is lowered corresponding to a convex portion existing on the nozzle forming surface side.
[0024]
Preferably, a head cover is attached to an edge of the nozzle forming surface of the liquid ejecting head, and the predetermined height distribution of the backrest portion is formed on the nozzle forming surface side by the presence of the head cover. And lower portions corresponding to the projected portions.
[0025]
In order to solve the above problem, a liquid ejecting apparatus according to the present invention includes a liquid ejecting head that ejects droplets from a nozzle opening toward a target, and any one of the wiping devices described above. .
[0026]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an ink jet recording apparatus as one embodiment of a liquid ejecting apparatus according to the present invention will be described with reference to FIGS.
[0027]
FIG. 1 is a perspective view showing a schematic configuration of the ink jet recording apparatus according to the present embodiment. In FIG. 1, reference numeral 1 denotes a carriage. The carriage 1 is guided by a guide member 4 via a timing belt 3 driven by a carriage motor 2, and is reciprocated in the axial direction of a platen 5. I have. The carriage 1, the carriage motor 2, the timing belt 3, and the guide member 4 constitute a carriage mechanism (main scanning mechanism) that scans the inkjet recording head 12 together with the carriage 1 in the main scanning direction.
[0028]
Further, the ink jet recording apparatus includes a feed mechanism (sub-scanning mechanism) that intermittently conveys the recording paper 6 on which recording is performed by the recording head 12 in a sub-scanning direction orthogonal to the main scanning direction.
[0029]
The carriage mechanism and the feed mechanism constitute a scanning unit that changes the relative positional relationship between the recording paper 6 and the recording head 12 during processing in order to change the landing position of the ink droplet on the recording paper 6.
[0030]
FIG. 2 is an enlarged perspective view of the recording head 12, and as shown in FIG. 2, the recording head 12 fixes a nozzle plate 12b including a nozzle forming surface 12a to a head casing 12d by a head cover 12c. It is configured. A large number of nozzle openings 12e are arranged on the nozzle forming surface 12a in a plurality of rows (six rows in this example). The recording head 12 is mounted on the side of the carriage 1 facing the recording paper 6, and an ink cartridge 7 for supplying ink to the recording head 12 is detachably mounted on the upper part thereof.
[0031]
A cap member 13 is disposed at a home position (right side in FIG. 1), which is a non-printing area of the ink jet recording apparatus. The cap member 13 moves the recording head 12 mounted on the carriage 1 to the home position. At times, the recording head 12 is configured to be pressed against the nozzle forming surface 12a to form a closed space between the recording head 12 and the nozzle forming surface 12a. A pump unit 10 for applying a negative pressure to a closed space formed by the cap member 13 is disposed below the cap member 13.
[0032]
In the vicinity of the cap member 13 on the printing region side, a wiping device 20 having an elastic blade such as rubber is arranged so as to be able to advance and retreat in a horizontal direction, for example, with respect to the movement locus of the recording head 12. The wiping device 20 is configured to wipe the nozzle forming surface 12a of the recording head 12 as necessary when the carriage 1 moves from the cap member 13 side to the printing area side.
[0033]
FIG. 3 is an enlarged perspective view of the wiping device 20 according to the present embodiment. As shown in FIG. 3, the wiping device 20 includes a rectangular flat plate-shaped blade member 21 made of an elastic material such as rubber. , A holder member 22 for holding the blade member 21.
[0034]
The blade member 21 is composed of a front end portion 21a including a straight front end contacting the nozzle forming surface 12a of the recording head 12 and a base end portion 21b inserted and fixed inside the holder member 22. Made up of
[0035]
The holder member 22 includes a main body portion 22a including a space for receiving the base end portion 21b of the blade member 21, and a lever portion 22b formed integrally with the main body portion 22a. The lever portion 22b is incorporated in the main body of the recording apparatus so as to be able to rotate together with the main body portion 22a about the rotation axis O shown in FIG. That is, the blade member 21 waiting at a position deviating from the movement locus of the recording head 12 is disposed around the movement locus of the recording head 12 by rotating the blade member 21 about the rotation axis O when performing the wiping operation. .
[0036]
Further, in the wiping device 20 according to the present embodiment, the holder member 22 includes a backrest portion 22c that supports the blade member 21 that is bent when sliding on the nozzle forming surface 12a in the bending direction.
[0037]
The backrest portion 22c has a predetermined height distribution in which the height changes along the width direction of the blade member 21 perpendicular to the direction of movement of the recording head 12, whereby the bendable portion of the blade member 21 is provided. The free length L (L1, L2), which is the length of the blade member 21, has a predetermined length distribution along the width direction of the blade member 21.
[0038]
More specifically, the backrest portion 22c includes a pair of convex portions 22d formed near both ends in the width direction. The pair of convex portions 22d extend in the moving direction (wiping direction) of the recording head 12 formed on the nozzle forming surface 12a side due to the presence of the head cover 12c attached to the periphery of the nozzle forming surface 12a of the recording head 12. It corresponds to the existing step portion S. In addition, the free length L1 of the blade member 21 in a portion substantially corresponding to the nozzle forming region A shown in FIG. 2 is such that the pressing force of the blade member 21 against the nozzle forming region A is appropriately large without excess or shortage. Set to length.
[0039]
FIG. 4 illustrates a state in which the nozzle forming surface 12a of the recording head 12 is wiped by the wiping device 20 illustrated in FIG. The wiping operation is performed by moving the recording head 12 while pressing the blade member 21 of the wiping device 20 against the nozzle forming surface 12a of the recording head 12.
[0040]
In the wiping device 20 according to the present embodiment, a pair of convex portions 22d are formed on the backrest portion 22c in correspondence with the step portions S extending in the wiping direction, where the remaining ink is likely to be wiped. As a result, the free length L of the blade member 51 is reduced to the short length L2, so that the blade member 51 in this portion is less likely to bend than the other portion (the portion of the free length L1). That is, at the portion corresponding to the pair of convex portions 22d, the pressing force of the blade member 21 against the recording head 12 is larger than the pressing force against the nozzle formation region A. Accordingly, a sufficient wiping effect can be obtained for the step portion S while securing an appropriate pressing force that is not excessive or insufficient for the nozzle formation region A, and it is possible to prevent the remaining ink from being wiped.
[0041]
In addition, since the pressing force against the portion other than the portion corresponding to the step portion S of the recording head 12 (that is, the nozzle forming region A) is normal, the destruction of the processing such as plating applied to the nozzle forming surface 12a is prevented. It is not accelerated, the wear of the blade member 21 is not accelerated, and the scattering of ink when the bent blade member 21 is restored does not increase.
[0042]
Further, according to the present embodiment, it is not necessary to process the blade member 21 made of an elastic material such as rubber which is generally difficult to process into a complicated shape, and it is possible to cope by changing the shape of the holder member 22 mainly formed of resin. As a result, the production cost is not significantly increased, and the trial production and its evaluation can be performed easily and at low cost.
[0043]
Further, according to the present embodiment, even if the concave and convex shape on the nozzle forming surface 12a side of the recording head 12 is changed due to a design change, it is possible to cope only by changing the shape of the holder member 22. Since the same can be used regardless of the design change of the recording head 12, it is not necessary to change the design of the blade member 21 according to the design change of the recording head 12.
[0044]
Next, another embodiment of the present invention will be described with reference to FIGS. Note that a description of parts common to the above-described embodiments will be omitted, and different parts will be described.
[0045]
As can be seen from FIGS. 5 and 6, in the wiping device according to the present embodiment, instead of providing a pair of convex portions 22d on the backrest portion 22c as in the above-described embodiment shown in FIG. A pair of notches 22e were formed at both ends in the width direction. The pair of notches 22e are formed corresponding to the protrusions P formed in the periphery of the nozzle forming surface 12a due to the presence of the head cover 12c and extending in the moving direction (wiping direction) of the recording head 12. .
[0046]
As described above, in the present embodiment, a pair of notches 22e are formed corresponding to the protrusions P extending in the moving direction (wiping direction) of the recording head 12, and the free length of the blade member 21 in these portions is formed. L3 is longer than the free length L1 of the blade member 21 at the portion corresponding to the nozzle formation region A.
[0047]
This prevents the pressing force of the blade member 21 against the portion (convex portion P) of the head cover 12c from becoming excessively large. As a result, the blade member 21 corresponding to the nozzle forming region A is moved to the portion (head portion 12c) of the head cover 12c. The phenomenon in which the blade member 21 corresponding to the convex portion P) is pulled laterally outward by the blade member 21 can be suppressed.
[0048]
For this reason, the followability (following) of the shape of the blade member 21 to the step portion S formed on the nozzle forming surface 12a side due to the presence of the head cover 12c is enhanced, and the remaining ink near the step portion S is prevented from being wiped off. can do.
[0049]
【The invention's effect】
As described above, according to the present invention, the back portion of the holder member that holds the blade member is provided with a predetermined height distribution in which the height changes along the width direction of the blade member, The free length, which is the length of the bendable portion of the member, has a predetermined length distribution along the width direction of the blade member. Therefore, when there is unevenness on the nozzle forming surface side of the liquid ejecting head. Also, the liquid on the liquid ejecting head can be wiped without hindrance.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an ink jet recording apparatus as one embodiment of a liquid ejecting apparatus according to the present invention.
FIG. 2 is an enlarged perspective view of a recording head of the ink jet recording apparatus shown in FIG.
FIG. 3 is a perspective view showing a wiping device as one embodiment of a wiping device for a liquid jet head according to the present invention.
FIG. 4 is a diagram illustrating a state where the nozzle forming surface of the recording head is wiped by the wiping device illustrated in FIG. 3;
FIG. 5 is a perspective view showing a wiping device as another embodiment of the wiping device for a liquid jet head according to the present invention.
FIG. 6 is a diagram illustrating a state where the nozzle forming surface of the recording head is wiped by the wiping device illustrated in FIG. 5;
FIG. 7 is a perspective view showing a conventional liquid ejecting head wiping device.
8 is a diagram showing a state where the nozzle forming surface of the recording head is wiped by the conventional wiping device shown in FIG. 7;
[Explanation of symbols]
Reference Signs List 12 recording head 12a nozzle forming surface 12b nozzle plate 12c head cover 12d head casing 12e nozzle opening 20 wiping device 21 blade member 21a distal end portion 21b of blade member base end portion 22 of blade member holder member 22a body portion 22b of holder member Holder Lever portion 22c of member Backrest portion 22d Convex portion 22e of backrest Notch portion A of backrest Nozzle forming region P Convex portion S Step portion

Claims (6)

A wiping device for wiping a nozzle forming surface of a liquid ejecting head that ejects liquid droplets from a nozzle opening toward an object,
A blade member made of an elastic material, which is in contact with the nozzle forming surface of the liquid ejecting head and slides on the nozzle forming surface by a relative movement with respect to the liquid ejecting head;
And a holder member for holding the blade member,
The blade member has a distal portion including a straight distal portion abutting on the nozzle forming surface, and a proximal portion fixed to the holder member,
The holder member includes a back portion that supports the blade member that is bent when sliding on the nozzle forming surface on a bending direction side thereof,
The backrest portion has a predetermined height distribution in which the height changes along a width direction of the blade member orthogonal to a moving direction of the liquid ejecting head, whereby a bendable portion of the blade member is provided. A wiping device for a liquid jet head, wherein a free length, which is the length of the blade member, has a predetermined length distribution along the width direction of the blade member. 2. The wiping device for a liquid jet head according to claim 1, wherein the predetermined height distribution of the backrest portion includes a portion that is raised corresponding to a step portion existing on the nozzle forming surface side. 3. A head cover is attached to an edge of the nozzle forming surface of the liquid ejecting head,
3. The wiping device for a liquid jet head according to claim 2, wherein the predetermined height distribution of the backrest portion includes a portion that is raised corresponding to a step portion formed on the nozzle forming surface side due to the presence of the head cover. 4. The wiping device for a liquid jet head according to claim 1, wherein the predetermined height distribution of the backrest portion includes a portion that is reduced corresponding to a convex portion existing on the nozzle forming surface side. 5. . A head cover is attached to an edge of the nozzle forming surface of the liquid ejecting head,
5. The wiping device for a liquid jet head according to claim 4, wherein the predetermined height distribution of the backrest portion includes a portion which is lowered corresponding to a convex portion formed on the nozzle forming surface side due to the presence of the head cover. A liquid ejecting head that ejects droplets from a nozzle opening toward an object,
A liquid ejecting apparatus comprising: the wiping device according to claim 1.

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