JP2001310475A - Ink-jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of a water repelling agent on an ejection opening surface of a recording head, to certainly clean the vicinity of the ejection opening provided in a recessed part, and to prevent the ink ejection failure simply and inexpensively by preferably cleaning even with a small contact force. SOLUTION: In order to wipe and clean an ejection opening surface 81 of a recording head 6, a plurality of plate-like blades 21a, 21b and 21c are arranged side by side in the wiping direction, with the free length of the blades set equally or reduced in the order of contacting with the ejection opening surface. The blade 21c to be contacted finally is made of an ether-based urethane, and the other blades 21a and 21b are made of an HNBR.

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 recording on a recording medium by discharging ink from recording means, and more particularly to a recovery system blade for maintaining the reliability of the recording means. is there.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile or the like, or a recording device (printing device) used as an output device such as a composite electronic device including a computer or a word processor or a workstation is an image forming device. Based on the information (recorded information)
2. Description of the Related Art Ink jet recording apparatuses that perform recording by ejecting ink toward a recording medium (recording material) such as paper, cloth, a plastic sheet, and an OHP sheet have become widespread. In addition, there are various demands for the material of these recording media, and in recent years, developments in response to these requirements have progressed, and paper (including thin paper and processed paper) and resin thin plates (such as OHP sheets) which are ordinary recording media have been developed. Besides, cloth, leather, non-woven fabric,
Further, a recording apparatus using a metal or the like as a recording medium has been used.

[0003] The ink jet recording apparatus has low noise,
It is widely applied to printers, copiers, facsimile machines, etc. from the viewpoints of low running cost, easy downsizing of the apparatus and easy colorization. Recording means (inkjet recording head) of inkjet recording apparatus
A discharge port (usually a plurality) for discharging ink droplets is formed on the front surface of the printer. The size of the discharge port is about several tens of microns. Is getting smaller and smaller. An ink droplet is ejected from the ejection port based on an ejection signal processed in the printing apparatus based on print data sent from the host machine, and an image (including characters and symbols) is printed on a printing medium. Is recorded.

However, in the ink jet recording apparatus, since the ink is ejected from the small ejection port as described above,
The ink in the vicinity of the discharge port is easily affected by the humidity of the environment and the like, and this ink dries and solidifies (referred to as “fixation”), making it impossible or difficult to discharge the ink from the discharge port when the next image signal comes. In addition, the quality of a recorded image may be significantly degraded due to an ejection failure. Therefore, in order to prevent such a phenomenon, when printing is not performed, the cap is pressed against the ejection port surface (the surface on which the ejection port is formed) of the recording head (recording means) with an appropriate pressure so that the ejection port is pressed. Isolation from outside air (capping) is performed.

Further, even when the above-described capping operation is performed, the discharge port may be clogged. In such a case, a suction recovery operation is performed. This suction recovery operation is performed by operating a pump (a negative pressure generating source) connected to the cap while the cap is pressed against the discharge port surface of the recording head to generate a negative pressure in the cap. The ink is sucked from the discharge port while refreshing the ink at the discharge port while destroying the fixed layer of ink at the outlet, and the operation is performed to eliminate the clogging of the discharge port.

[0006] As a negative pressure generating source for such a suction recovery operation, a cylinder type pump, a tube pump or the like is used. The cylinder type pump generates a negative pressure as the piston moves, and is characterized in that a large negative pressure is obtained. On the other hand, the tube pump generates a negative pressure in the tube by a restoring force of the tube itself after the tube is squeezed by a roller.

Further, during recording, not all the ejection ports of the recording head eject ink, and there are ejection ports that are not used (do not eject ink) at all during a certain time (period). is there. In addition, during recording, the ejection port is exposed to wind corresponding to the recording speed, and the ink in the ejection port is easily dried and a fixed layer is easily generated in the ejection port. In order to avoid the occurrence of such an ink fixing layer, it is necessary to discharge ink from all or some of the ejection ports of the recording head to refresh the ink in the ejection ports when printing is performed continuously for a certain period of time. . For such a purpose, a recovery operation called preliminary ejection (preliminary ejection) is performed.

In the above-mentioned preliminary discharge, discharging (discharging) the ink into the cap is widely performed. In the case of preliminary discharge performed by discharging ink into such a cap, when the preliminary discharge amount reaches a certain amount, the pump is operated to suction the preliminary discharge ink (waste ink) in the cap and discharge it to the outside. It is configured to be. As described above, the functions of the cap in the ink jet recording apparatus can be roughly divided into about three functions.

Next, the situation near the ejection port surface of the recording head will be described. Since a recording medium such as recording paper passes through the recording apparatus, paper dust or the like adhering to the recording paper may flutter or float inside the recording apparatus. Garbage such as paper powder adheres to the exit,
Ink ejection is hindered, resulting in non-ejection, which can significantly degrade image quality. Before such a situation, it is necessary to clean the discharge port surface by automatically wiping the discharge port surface with a blade at a certain time interval. Further, when the image deterioration happens to occur due to the non-ejection of the ink, the user may wipe the ejection port surface based on the manual.

Further, since the ink is frequently ejected from the ejection port, the amount of ink ejected from the ejection port is reduced from tens of picoliters to several picoliters. In some cases, the ink may fly in a mist state, or a part of the ink flying toward the recording medium may rebound when the ink collides with the paper surface, and the rebounded ink may adhere to the ejection opening surface of the recording head. If such a situation continues, even small ink droplets adhering to the ejection port surface will grow and cover the ejection port, preventing ink ejection and causing non-ejection, resulting in a significant decrease in image quality. May be. Even before such a situation occurs, it is necessary to clean the discharge port surface by automatically wiping the discharge port surface with a blade at a certain time interval. Also, if image deterioration happens to occur due to non-ejection of ink,
The user may wipe the discharge port surface based on a manual.

Further, as described above, the cap is pressed against the ejection opening surface of the recording head, and the cap itself is formed by ink ejected preliminarily to the inside or ink sucked by the pump through the inside. Ink has been contaminated, and ink has adhered to the ejection port surface after the cap pressure release. For this reason, if the recording is performed as it is after the cap pressure release, the ink may not be ejected. In order to prevent non-discharge of ink and deterioration of image quality, a sequence of wiping (wiping and cleaning) the discharge port surface with the blade after the cap pressure contact is released is adopted. However, even if the above-described various sequences for eliminating non-ejection of ink are adopted, a technical problem that deterioration of image quality due to non-ejection cannot be completely prevented remains.

In recent recorded images, there is a strong demand for higher density of black, higher color, higher definition, higher water resistance, and the like, and accordingly, the form of the recording head has changed. In general, in a serial type ink jet recording apparatus, a recording head is mounted on a carriage, and a dot image is recorded on a recording medium (recording paper) by driving the recording head in synchronization with the reciprocating movement of the carriage. A dot matrix is formed in the main scanning direction and the paper scanning sub-scanning direction, thereby recording an image. Depending on the type of image formed at this time, one or more recording heads are mounted on the carriage. In particular, when high-quality images are demanded at a low cost, only one print head can be mounted on the carriage, and a user operates a printing apparatus while replacing a plurality of types of print heads one by one to obtain high-quality images. Has been realized.

For example, to perform color recording while increasing the density of black, a pigment head for recording with a pigment having a higher density than the dye is attached to the carriage at the time of black recording, and then replaced with a color head at the time of color recording. I do. Here, since a pigment color head is difficult to realize, a dye head is used as the color head. In this case, since the head is attached to the carriage at one location, the caps corresponding to the pigment head and the color head are also provided at one location (one).
Is provided. That is, a configuration is adopted in which the same (common) cap is used for the pigment head and the dye head.

Further, when black recording which does not normally require water resistance is performed at a high speed, and color recording is also performed at a moderate speed, a black recording head and a color recording head are used.
A carriage system equipped with a plurality of recording heads is employed. However, in this case, when a water-resistant black recording or a water-resistant color image is desired to be obtained with this system, a processing solution that provides water resistance to one of the head insertion pockets of a carriage capable of mounting two recording heads. A recording system (system) for obtaining a water-resistant black image or a color image by inserting a recording head filled with a recording head and mounting a black recording head or a color recording head in the other insertion pocket is adopted. .

In this system, the carriage 2
In this configuration, two caps are provided at positions corresponding to the head pockets, and these caps are pressed against the respective recording heads. In this system, a cap pressed against a recording head filled with a processing liquid may be pressed against a black recording head or a color recording head. Such a configuration has the following technical problems to be solved.

That is, first, the ink itself discharged from the discharge port is a black pigment ink having a high density,
Since the ink is a reactive ink (treatment liquid) that reacts with other inks on the paper surface to exhibit water resistance, the wiping ability of the discharge port surface of the recording head by the blade is considerably deteriorated. . That is, the pigment ink has a higher viscosity than the dye ink, and the particles have a particle size of 0.1 μm to 0.2 μm.
The size of the discharge port is much larger than that of the dye. Further, since the recording head filled with the reactive ink (processing liquid) and the recording head filled with the dye ink are arranged in parallel in the main scanning direction, both recordings are performed by mist-like ink mist or ink rebounding from the paper surface. When the processing liquid and the ink are mixed with the ink adhering to the discharge port surface of the head, a stable fixed film is formed on the discharge port surface by reacting, and the fixed film covers the discharge port. Ink ejection from the outlet is hindered, and non-ejection occurs.

Second, a part of the discharge port surface may be concave due to the manufacturing method (processing method) of the discharge port of the recording head. In a system using a processing liquid, ink is more likely to accumulate in the recesses, so that the wiping performance of the ejection port surface by the blade is further deteriorated, and the ejection port of the recording head is blocked, which tends to cause non-ejection. It will be significantly deteriorated. This will be described in more detail with reference to FIGS.

FIG. 9 is a partial perspective view showing a wiping mechanism of a conventional ink jet recording apparatus, and FIG. 10 is a front view of the recording head viewed from the direction of arrow B in FIG.
1 is a longitudinal sectional view taken along line CC in FIG. FIG. 9 is a diagram showing the relationship between the recording head 306 and the recovery system 317. In this conventional example, the number of recording heads 306 is one.
The number of the cap 318 of the recovery system 317 is also one. 9 to 11, the recording head 306 is configured to select one of a pigment head 361 dedicated to black and a color dye head 362 and mount it on the carriage 314 for use. One cap 318 for recovery system 317
Is provided, and when ink is to be sucked from the ejection port of the recording head 306, the cap 318 is provided by means (not shown).
Is pressed against the recording head 306 and a pump (negative pressure generating source) connected to the cap 318 is operated to generate a negative pressure suction force.

The recovery system 317 has one blade 32
3 are provided. The blade 323 is supported by the blade holder 320 so that it can be taken in and out (movable forward and backward). When wiping and cleaning (wiping) the ejection port surface of the recording head 306, the blade 323 is advanced toward the ejection port surface of the recording head 306 by a driving unit (not shown) to be in a protruding state, and in this state, the carriage 314 is moved. By moving the recording head 3 in the direction of arrow A,
06 can be wiped. On the other hand, FIG. 10 and FIG.
As shown in FIG. 7, a concave portion 306b in a semicylindrical shape is formed, and discharge ports 306c arranged in a line are formed in the concave portion 306b.

In such a configuration of the recording head 306, unwiped portions 306d are formed at two positions near the upper and lower ends of the concave portion 306b, and the ink of these unwiped portions covers a part of the discharge port 306c and discharges. The phenomenon of non-discharge at the outlet occurs. In addition, the depth of the concave portion 306b in the embodiment is about 0.3 mm.

[0021]

The above-described conventional ink jet recording apparatus has the following technical problems to be solved. That is, first, in the case of a recording head (recording means) using a pigment ink or a reactive ink (processing liquid), the ink is firmly attached (fixed) to the ejection port surface of the recording head, and thereby the ejection port is Is blocked and a non-ejection phenomenon occurs, and the image quality is remarkably deteriorated.

Although a water-repellent agent is applied to the discharge port surface of the recording head in order to prevent ink from adhering to the vicinity of the discharge port and causing non-discharge, it is strongly adhered to the discharge port surface of the recording head. If wiping is performed by increasing the pressing force of the blade in order to remove the ink, the water repellent is particularly peeled off, and the recording head is destroyed.

The present invention has been made in view of such a technical problem, and an object of the present invention is to make it possible to reliably perform cleaning even with a small pressing force, so that a repellent material coated on the discharge port surface can be obtained. The durability of the liquid agent can be improved, and even when the discharge port is formed in the concave portion of the discharge port surface, the periphery of the discharge port can be reliably cleaned. An object of the present invention is to provide an ink jet recording apparatus capable of performing highly reliable recording by preventing ejection failure such as non-ejection or twisting.

[0024]

Means for Solving the Problems The present invention (claim 1) provides:
In order to achieve the above object, in an ink jet recording apparatus that discharges ink from a recording unit to perform recording on a recording medium, a plurality of plate-like blades for wiping and cleaning an ejection port surface of the recording unit are arranged in a wiping direction. In addition, the free length of each blade is substantially the same. The invention according to claims 2 and 3 has a structure in which the plurality of blades are formed of a plurality of materials, in addition to the structure of the above-described claim 1.
Alternatively, the material of the plurality of blades may be more efficiently used in the order in which the blades are made of ether urethane and the other blades are HNBR in the order in which the blades are in contact with the ejection port surface of the recording means. To achieve.

According to another aspect of the present invention, in order to achieve the above object, in an ink jet recording apparatus for recording on a recording medium by discharging ink from the recording means, the ejection port surface of the recording means is wiped and cleaned. A plurality of plate-shaped blades are arranged in the wiping direction, and the free length of each blade is selected so as to decrease in the order of contact with the discharge port surface of the recording means. The invention according to claims 5 and 6 is characterized in that, in addition to the constitution of claim 4, the plurality of blades are formed of a plurality of materials, or the material of the plurality of blades is a discharge port surface of a recording unit. In this case, the last blade is made of ether-based urethane and the other blades are made of HNBR so that the above object can be achieved more efficiently.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a configuration of a recording section of a first embodiment of an ink jet recording apparatus to which the present invention is applied, FIG. 2 is a side sectional view of the ink jet recording apparatus of FIG. 1, and FIG. FIG. 4 is a plan view of the inkjet recording apparatus, and FIG. 4 is a schematic partial perspective view showing a wiping mechanism of the inkjet recording apparatus of FIG.

1 to 3, a recording medium (recording paper) separated and fed one by one from an automatic sheet feeder (automatic paper feeder) 1 (FIG. 2) is fed onto a paper feed roller 2. And a first pinch roller 3 pressed against the paper feed roller 2.
After the orientation is adjusted (registered), the sheet is sandwiched between these rollers 2 and 3 and reaches the needle roller 5 as the second pinch roller while being curved and guided by the paper pan 4. Next, the recording medium is nipped by the paper feed roller 2 and the needle roller 5 and reaches a platen 7 arranged opposite to the recording head 6. With respect to the recording medium that has reached the position of the platen 7, ink droplets are ejected from ejection ports of the recording head 6 based on a recording signal transmitted from a host (not shown), and the ink droplets are fixed on the recording medium. To form an image (record). In this way, recording is performed when the recording medium is a cut sheet.

On the other hand, when the recording medium is continuous paper (for example, fan hold paper 16a), the fan hold paper 16a is set on the pin feed tractor 16, and the pinch roller 3 is moved from the paper feed roller 2 by a release lever (not shown). Release (separation) (the release position is indicated by 3 '),
Fan hold paper 16a is placed between these rollers 2, 3 '.
After that, the fan hold paper 16a is guided (guided) between the paper feed roller 2 and the paper pan 4 and fed while being pressed against the paper feed roller 2 and the needle roller 5. Transported). When the fan-hold paper 16a reaches the platen 7 facing the recording head 6 in the same manner as in the case of the cut sheet described above, the recording head 6 is driven based on the image data in synchronization with this, thereby forming an image ( Recording).

The recording medium (both cut paper and continuous paper) thus recorded is then conveyed while being sandwiched between the first discharge roller 8 and the first spur 9 opposed thereto, and then the second discharge The paper is conveyed while being pinched by the paper roller 10 and the second spur 11 opposed thereto, and further adjusted to a posture in which the direction is changed by the second discharge roller 10 and the third spur 13 opposed thereto to be stably stacked. Thereafter, the paper is discharged to the paper discharge stacker 12 and stacked there.

Here, the first pinch roller 3 and the needle roller (second pinch roller) 5 press the recording medium (recording paper) against the paper feed roller 2 with an appropriate pressing force. Demonstrates the power to convey. Also,
Since the peripheral speed is increased in the order of the first paper discharge roller 8 and the second paper discharge roller 10 than the paper feed roller 2, tension is applied to the recording medium (recording paper) being conveyed, The recording paper is fed by this tension while forming a stable flat surface. Further, at a position very close to the recording head 6, it is desirable to stabilize the recording sheet by preventing or reducing the floating of the sheet in the recording section. For this purpose, a configuration is adopted in which the recording sheet is pressed down.

In other words, the diameter of the needle roller 5 is selected to be as small as possible from the viewpoint of improving the quality of the recorded image by pressing the recording paper very close to the recording head 6 as described above. Is selected to be about 2 mm. The carriage 14 on which the recording head 6 is mounted reciprocates in a direction crossing (usually orthogonal to) the paper feeding direction of the recording paper while being guided and supported along a carriage shaft (guide shaft) 15 and based on image information. Recording is performed by discharging ink from the recording head 6 onto recording paper. A home position of the carriage 14 is provided at a position outside the recording area (a position at the left end in FIGS. 1 and 3).
A recovery system 17 for recovering and maintaining the ink discharge performance of the recording means 6 is disposed at a position facing the recording means 6 (recording head) on the carriage when the carriage 14 is at the home position. Has been established.

The recording head (recording means) 6 is an ink jet recording means for discharging ink using thermal energy, and is provided with an electrothermal converter for generating thermal energy. Further, the recording head 6 includes:
The recording is performed by discharging ink from the discharge port by utilizing a pressure change generated by the growth and shrinkage of bubbles caused by film boiling caused by the heat energy applied by the electrothermal transducer.

FIG. 8 is a partial perspective view schematically showing the structure of the ink ejection section of the recording head 6. As shown in FIG. In FIG. 8, a predetermined gap (for example, about 0.3 to 2.0
A plurality of discharge ports 82 are formed at a predetermined pitch on the discharge port surface 81 facing at a distance of about millimeters, and along a wall surface of each liquid path 84 communicating the common liquid chamber 83 and each discharge port 82. An electrothermal converter (heating resistor or the like) 85 for generating energy for ink ejection is provided. In this embodiment, the recording head 6 is configured such that the ejection port 82 is
With a positional relationship such that they are arranged in a direction that intersects the scanning direction of 4,
It is mounted on the carriage 14. Thus, the corresponding electrothermal converter 8 based on the image signal or the ejection signal
The recording head 6 drives (energizes) the ink 5 in the liquid path 84 to boil the ink in the liquid path 84 and discharges the ink from the discharge port 82 by the pressure generated at that time.

FIG. 4 is a schematic partial perspective view showing a first embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied. In FIG. 4, the carriage 14 is at the home position and the cap 18 is a recording head (recording means).
6 shows the relationship between the recording head (recording means) 6 and the recovery system 17 when the recording head 6 is separated from the recording head 6. In this embodiment, one recording head 6 is provided, and one cap 18 of the recovery system 17 is also provided. ing. In FIG. 4, as the recording head 6 mounted on the carriage 14, one of a pigment recording head 61 dedicated to black recording and a dye recording head 62 for color recording is selected, and only one recording head is mounted on the carriage 14. It is configured to be mounted on. Correspondingly, the recovery system 17 is provided with one cap 18.

In FIG. 4, the discharge port 82 of the recording head 6
When performing a suction recovery process for sucking ink from the ink jet head, the cap 18 is pressed against the ejection port surface 81 of the recording head 6 to bring the cap 18 into a capping state by means (not shown), and then a negative pressure source connected to the cap 18 is connected. By operating the (pump) to bring the inside of the cap into a negative pressure state, an operation is performed such that ink is sucked from the ejection port 82 through the cap. After performing the suction recovery process or after separating the cap 18 from the recording head 6 (after opening the cap), wiping (wiping and cleaning) of the discharge port surface 81 by the blade group 19 including a plurality of blades is performed. That is, a plurality of plate-like blades 19a, 19b, and 19c for wiping and cleaning the ejection port surface 81 of the recording unit (recording head) 6.
Are arranged at predetermined intervals in the wiping direction (the moving direction of the carriage 14). Reference numeral 19d denotes a blade holder that supports the blade group 19.

When the recording head 6 (actually, the pigment recording head 61 for black recording or the dye recording head 62 for color recording) moves in the direction of arrow D, the blade group 19 performs recording by utilizing this operation. After passing through the head 6, the head 6 is configured to advance to a projected state. When the recording head 6 moves in the direction of arrow E, the blade group 19
Thus, the ejection port surface 81 of the recording head 6 is wiped (wiped and cleaned). The blade group 19 is composed of three blades 19a, 19b, and 19c arranged at predetermined intervals in the wiping direction (the direction of arrow E).
9b and 19c are contacted in this order.

In the first embodiment shown in FIG. 4, the blades 19a, 19b, 19c
The free length, which is the distance from the mounting portion (the front surface of the blade holder 19d)) to the tip (free end), is set to the same size (all three). And blade 19
a, 19b are relatively inexpensive butyl rubber HNB
R, and the material of the blade 19c is selected to be a relatively expensive ether urethane rubber suitable for finishing. In other words, the material of the plurality of blades is such that the last blade 19c is an ether-based urethane and the other blades 19a and 19b are functionally approximately the discharge port surfaces in the order of contact with the discharge port surface 81 of the recording means 6. HNBR is selected as a level that can be wiped.

The last blade 19c is a finished expensive ether-based urethane rubber, and is processed with extremely high edge precision in order to maintain a high wiping performance when wiping the discharge port surface of the recording head 6. . As a result, only the last blade 19c is a relatively more expensive component than the other blades. Conversely, the last blade 19
Since only c is machined with high precision, the cost of the entire blade group 19 can be reduced, and the cost performance can be improved. Furthermore, the contact pressure of the three blades 19a, 19b, 19c against the discharge port surface 81 is set to a small value (for example, a small pressure) so that the water repellent on the discharge port surface does not peel off.

According to the first embodiment described above with reference to FIG. 4, even if the discharge port surface 81 of the recording head 6 is concave (see the concave portion 306b in FIG. 10), the discharge port surface 3 is formed. Since the blades pass with an appropriate contact pressure, it is possible to reliably remove the ink droplets to the region of the concave portion. In addition, a blade group having a low total cost and a high cost performance can be formed, and a highly reliable ink jet recording apparatus capable of easily recovering and maintaining the ink ejection performance can be obtained. That is, the ejection port surface 81 of the recording means 6 is made to have a plurality of blades 19a, 19b, 19
Since the wiping is sequentially performed in multiple stages in step c, the durability of the water-repellent agent coated on the discharge port surface 81 can be improved by enabling reliable cleaning even with a small pressure contact force. Even when the discharge port 82 is formed in the concave portion (see the concave portion 306b in FIG. 10) of the outlet surface 81, the periphery of the discharge port can be reliably cleaned, and therefore, the ink is not discharged in a simple and inexpensive configuration. Provided is an ink jet recording apparatus capable of performing highly reliable recording by preventing ejection failures such as ink jetting and misalignment.

FIG. 5 is a schematic partial perspective view showing a second embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied. In the first embodiment shown in FIG. 4, the free lengths of the blades 19a, 19b, and 19c constituting the blade group 19 are the same, but in the present embodiment, the free lengths of the blades 21a, 21b, and 21c constituting the blade group 21 are provided. Are selected so as to gradually decrease in the order of contact with the discharge port surface 81 of the recording means (recording head) 6. That is, the second in FIG.
Also in the embodiment, the recording head 6 (either the pigment head 61 dedicated to black or the color dye head 62 in the illustrated example).
To clean the discharge port surface 81 of the
Plate-like blades 21a, 21b, 21c are disposed in the wiping direction (direction of arrow E), but in this embodiment,
The free length of each blade is selected so as to gradually decrease in the order of contact with the discharge port surface 81 of the recording head 6.

In the second embodiment shown in FIG. 5, as in the first embodiment shown in FIG. 4, a plurality of blades 21a, 21b and 21c (two or more types) are included in the blade group 21. More specifically, the blade 2 that comes into contact with the ejection port surface 81 of the recording head 6 lastly
1c is made of ether urethane, and the other blades 21a and 21b are made of HNBR. In this manner, similarly to the first embodiment of FIG. 4, the precision of the edge of the last blade 21c that affects the wiping property can be extremely increased, and a structure can be surely finished on a clean and clean surface. ing. That is, the second embodiment of FIG. 5 is different from the first embodiment of FIG.
a, 21b, and 21c are set to the recording head 6
Are different in that they are reduced in the order in which they come into contact with the discharge port surface 81, but in other respects they have substantially the same configuration, and corresponding parts are denoted by the same reference numerals, and detailed description thereof is omitted. I do.

According to the second embodiment shown in FIG. 5, the same effect as that of the first embodiment shown in FIG. 4 can be obtained, and the free length of each of the blades 21a, 21b, 21c of the blade group 21 can be reduced. , The interference between the blades can be easily eliminated, and the arrangement pitch (arrangement interval) of the blades can be set small. Therefore, the space efficiency and compactness can be further improved. There is an effect that a wiping mechanism can be realized.

FIG. 6 is a schematic partial perspective view showing a third embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied. In the present embodiment, a blade group 30 including a plurality of plate-like blades 30a, 30b, and 30c arranged at predetermined intervals on an endless belt 25 that can travel in the vertical direction is provided integrally, By driving the endless belt 25 in the direction of arrow F by the drive source, the plurality of blades 30a, 30b, and 30c are moved from top to bottom while the recording head 6 (also in this embodiment, the pigment head 61 dedicated to black and the color dye One of the heads 62)
Is wiped off and cleaned. That is, the blade group 30 includes three blades 30a, 30b, 30 arranged at predetermined intervals in the wiping direction (up and down direction).
The endless belt 25 is driven by a driving source (not shown), so that the ejection port surface 81 of the recording head 6 is formed.
, 30a, 30b, and 30c in this order and wiped from top to bottom for cleaning.

Accordingly, in the third embodiment shown in FIG. 6, each of the blades 30a, 30b, 30
The free length, which is the distance from the mounting portion c (the surface of the endless belt 25) to the tip (free end), is set to the same size (all three). As the material of the plurality of blades constituting the blade group 30, a plurality of types of materials are selected in the same manner as in the above-described embodiment. Specifically, as the material of the plurality of blades, the last (finished) blade 30 is arranged in the order in which it comes into contact with the discharge port surface 81 of the recording means 6.
c is selected as a relatively expensive ether-based urethane suitable for finishing, and the other blades 30a and 30b are selected as HNBRs at a level where the discharge port surface can be functionally wiped substantially. Furthermore, these three blades 30a,
The contact pressure of the discharge port surfaces 81 of the discharge port surfaces 30b and 30c is set to a small value (for example, a small pressure) so that the water repellent on the discharge port surfaces does not peel off.

In the third embodiment shown in FIG. 6, a plurality of blades 30a, 3
0b and 30c are provided, and the endless belt 25 is driven by a drive source (not shown) to wipe the discharge port surface 81 from top to bottom, which is different from the first embodiment of FIG. In this respect, they have substantially the same configuration, and corresponding portions are denoted by the same reference numerals, and detailed description thereof will be omitted. At the time of normal recording, the endless belt 25 has a portion where the blade does not exist.
Is stopped at a position facing the discharge port surface 81.

According to the third embodiment described above with reference to FIG. 6, the discharge port surface 81 of the recording head 6 is concave (FIG. 10).
(See FIG. 306b).
Since the blades pass with an appropriate contact pressure, it is possible to reliably remove the ink droplets to the region of the concave portion. In addition, a blade group having a low total cost and a high cost performance can be formed, and a highly reliable ink jet recording apparatus capable of easily recovering and maintaining the ink ejection performance can be obtained. That is, the discharge port surface 81 of the recording unit 6 is formed by a plurality of blades 30a, 30b, 30
Since the wiping is sequentially performed in multiple stages in step c, the durability of the water-repellent agent coated on the discharge port surface can be improved by enabling reliable cleaning even with a small pressure contact force. Even when the discharge port 82 is formed in the concave portion of the surface 81 (see the concave portion 306b in FIG. 10), the periphery of the discharge port 82 can be reliably cleaned, and therefore, the non-discharge of ink can be performed with a simple and inexpensive configuration. Provided is an ink jet recording apparatus capable of performing highly reliable recording by preventing ejection failures such as ink jetting and misalignment.

FIG. 7 is a schematic partial perspective view showing a fourth embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied. In the third embodiment shown in FIG. 6, the free length of each blade 30a, 30b, 30c constituting the blade group 30 is the same, but in the present embodiment, the free length of each blade 33a, 33b, 33c constituting the blade group 33 is provided. Are selected so as to gradually decrease in the order of contact with the discharge port surface 81 of the recording means (recording head) 6 (from bottom to top in FIG. 7). That is, in the present embodiment, the recording head 6 (in the illustrated example, the pigment head 61 dedicated to black and the color dye head 62
Wiping and cleaning the discharge port surface 81 of either one of the blades 33a, 33b,
Although 33c is disposed in the wiping direction, in this embodiment,
The free length of each blade is selected so as to gradually decrease in the order of contact with the discharge port surface 81 of the recording head 6.

In the fourth embodiment of FIG. 7, as in the case of the third embodiment of FIG. 6, the plurality of blades 33a, 33b, and 33c constituting the blade group 33 are plural (two or more types). Specifically, the blade 3 that is in contact with the ejection port surface 81 of the recording head 6 lastly
3c is formed of ether-based urethane, and the other blades 33a and 33b are formed of HNBR. In this manner, similarly to the third embodiment of FIG. 6, the precision of the edge of the last blade 33c which affects the wiping property can be extremely increased, and a structure can be surely finished on a clean and clean surface. ing. That is, the fourth embodiment of FIG. 7 is different from the third embodiment of FIG. 6 in that the free length of each of the plurality of blades is reduced in the order in which the blades contact the discharge port surface 81 of the recording head 6. However, it has substantially the same configuration in other respects. In the present embodiment, similarly to the third embodiment of FIG. 6, during normal printing, the endless belt 25 stops at a position where a portion where no blade exists is opposed to the discharge port surface 81 of the print head 6. I have.

According to the fourth embodiment of FIG. 7, the same effects as those of the first embodiment of FIG. 4 and the third embodiment of FIG. 3
Since the free lengths of 3b and 33c are gradually reduced in the order of wiping, interference between the blades can be easily eliminated, and the arrangement pitch (arrangement interval) between the blades can be set small. This has the effect of realizing a compact wiping mechanism that is more space efficient.

In the above-described embodiment, the serial recording method in which the recording means (recording head) 6 is moved in the main scanning direction has been described as an example. The present invention can be applied to a line recording system in which recording is performed only by sub-scanning using a line recording unit having a length covering a portion, and the same effect can be achieved. In addition, the present invention provides, in addition to an ink jet recording apparatus for performing single color recording, a color ink jet recording apparatus having one or a plurality of recording heads for recording with inks of different colors, and a gradation using inks of the same color and different densities. The present invention can be similarly applied to an ink jet recording apparatus and an ink jet recording apparatus in which these are combined, and can achieve the same effect.

Further, according to the present invention, when the recording means is a replaceable ink jet cartridge (head cartridge) in which a recording head section and an ink storage section are integrated,
Alternatively, the present invention can be similarly applied to a case where the recording unit and the ink storage unit take various forms, such as a case where the recording unit is a permanent type, and can achieve the same operation and effect. In addition, the present invention can be applied to an inkjet recording apparatus using a recording unit (recording head) using an electromechanical transducer such as a piezo element. This provides an excellent effect in an ink jet recording apparatus using a recording means of a type which discharges ink. According to such a method, it is possible to achieve higher density and higher definition of recording.

[0052]

As is apparent from the above description, according to the present invention (claim 1), in an ink jet recording apparatus for recording on a recording medium by discharging ink from the recording means, the discharge port surface of the recording means is used. A plurality of plate-like blades for wiping and cleaning are arranged in the wiping direction, and the free length of each blade is set to be substantially the same size. Since the wiping is performed in multiple stages, the durability of the water-repellent agent coated on the discharge port surface can be improved by enabling reliable cleaning even with a small pressing force, and the concave portion on the discharge port surface Even if a discharge port is formed, it is possible to reliably clean the periphery of the discharge port, and to prevent a non-discharge of ink or a discharge defect such as twisting with a simple and inexpensive configuration. An ink jet recording apparatus is provided which can perform highly reliable recording by.

According to the second and third aspects of the invention, in addition to the configuration of the first aspect, the plurality of blades are formed of a plurality of materials, or the material of the plurality of blades is a recording material. Since the last blade is made of ether-based urethane and the other blades are made of HNBR in the order of contact with the discharge port surface of the means, the above effects can be achieved more efficiently.

According to the fourth aspect of the present invention, in the ink jet recording apparatus which discharges ink from the recording means to perform recording on the recording medium, the plate-like blade for wiping and cleaning the discharge port surface of the recording means is wiped in the wiping direction. And the free length of each blade is selected so as to decrease in the order in which it comes into contact with the discharge port surface of the recording means. Since the wiping is performed in multiple stages, the durability of the water-repellent agent coated on the discharge port surface can be improved by enabling reliable cleaning even with a small pressing force, and the concave portion on the discharge port surface Even if the discharge port is formed, the area around the discharge port can be reliably cleaned,
Accordingly, there is provided an ink jet recording apparatus capable of performing highly reliable recording by preventing a non-discharge of ink or a discharge failure such as a twist with a simple and inexpensive configuration.

According to the fifth and sixth aspects of the invention, in addition to the configuration of the fourth aspect, the plurality of blades are formed of a plurality of materials, or the material of the plurality of blades is a recording material. Since the last blade is made of ether-based urethane and the other blades are made of HNBR in the order of contact with the discharge port surface of the means, the above effects can be achieved more efficiently.

[Brief description of the drawings]

FIG. 1 is a perspective view illustrating a configuration of a recording unit of a first embodiment of an inkjet recording apparatus to which the present invention has been applied.

FIG. 2 is a side sectional view of the inkjet recording apparatus of FIG.

FIG. 3 is a plan view of the ink jet recording apparatus of FIG.

FIG. 4 is a schematic partial perspective view showing a first embodiment of a wiping mechanism of the ink jet recording apparatus to which the present invention is applied.

FIG. 5 is a schematic partial perspective view showing a second embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied.

FIG. 6 is a schematic partial perspective view showing a third embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied.

FIG. 7 is a schematic partial perspective view showing a fourth embodiment of the wiping mechanism of the ink jet recording apparatus to which the present invention is applied.

FIG. 8 is a partial perspective view schematically showing a structure of an ink ejection unit of the recording unit in FIG.

FIG. 9 is a schematic partial perspective view showing a wiping mechanism of a conventional ink jet recording apparatus.

FIG. 10 is a front view of the recording unit as viewed from the direction of arrow B in FIG. 9;

11 is a vertical sectional view taken along line CC in FIG.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 auto sheet feeder 2 paper feed roller 3 pinch roller 4 paper pan 6 recording means (recording head) 7 platen 8 first paper discharge roller 10 second paper discharge roller 12 paper discharge stacker 14 carriage 15 carriage shaft (guide shaft) 16 pin Feed tractor 17 Recovery system 18 Cap 19 Blade group (blades 19a, 19b, 19
c) 19d blade holder 21 blade group (blades 21a, 21b, 21)
c) 25 endless belt 30 blade group (blades 30a, 30b, 30)
c) 33 blade groups (blades 33a, 33b, 33)
c) 61 Pigment recording head dedicated to black recording 62 Dye recording head for color recording 81 Discharge port surface 82 Discharge port 83 Common liquid chamber 85 Electrothermal converter

Claims (9)

[Claims] 1. An ink jet recording apparatus for recording on a recording medium by discharging ink from a recording means, wherein a plurality of plate-like blades for wiping and cleaning an ejection port surface of the recording means are arranged in a wiping direction, An ink jet recording apparatus, wherein the free length of each blade is substantially the same. 2. The ink jet recording apparatus according to claim 1, wherein the plurality of blades are formed of a plurality of materials. 3. The material of the plurality of blades is such that the last blade is an ether-based urethane and the other blades are HNBR in the order of contact with the discharge port surface of the recording means. The inkjet recording apparatus according to any one of the preceding claims. 4. An ink jet recording apparatus which discharges ink from a recording means to perform recording on a recording medium, wherein a plurality of plate-like blades for wiping and cleaning an ejection port surface of the recording means are arranged in a wiping direction, An ink jet recording apparatus, wherein the free length of each blade is selected so as to decrease in the order of contact with the discharge port surface of the recording means. 5. The ink jet recording apparatus according to claim 4, wherein the plurality of blades are formed of a plurality of materials. 6. The material of the plurality of blades, wherein the last blade is an ether-based urethane and the other blades are HNBR in the order of contact with the discharge port surface of the recording means. The inkjet recording apparatus according to any one of the preceding claims. 7. An ink jet recording apparatus according to claim 1, wherein said recording means is mounted on a carriage which moves in a direction intersecting a conveying direction of said recording medium. 8. The ink jet recording device according to claim 1, wherein said recording device is an ink jet recording device provided with an electrothermal converter for generating thermal energy used for discharging ink. 3. The ink jet recording apparatus according to claim 1. 9. The ink jet recording apparatus according to claim 8, wherein the recording means discharges the ink from a discharge port using film boiling generated in the ink by thermal energy generated by the electrothermal transducer. .