JP2005335404A - Inkjet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decrease generation of failure of printing caused by an influence of bubbles of an ink generated at the time when a cap unit is opened to the atmospheric air. <P>SOLUTION: In an inkjet recording apparatus equipped with the cap unit 38 for sucking the ink from a nozzle opening 15 of a recording head 8, an ink absorbing material 17 for absorbing the sucked ink from the nozzle opening 15 is arranged in the cap unit 38, and a dent such as a recessed part 17a or the like is formed on a part facing the nozzle opening 15 of this ink absorbing material 17. It becomes possible by this constitution to prevent the bubbles of the ink from being generated and reaching the nozzle opening, or to decrease its extent at the time when the cap unit is opened to the atmospheric air. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is an ink jet recording apparatus that has a recording head that moves in the width direction of a recording sheet, and performs printing on the recording sheet by ejecting ink droplets toward the recording sheet based on print data. More particularly, the present invention relates to a capping device for eliminating clogging of nozzle openings that eject ink droplets.

  Since graphic processing can be executed relatively easily with the development of personal computers, there is a need for a recording apparatus capable of outputting, for example, a hard copy of a color image displayed on a display with high quality. In order to meet such a demand, a recording apparatus equipped with an ink jet recording head is provided.

  This ink jet recording apparatus is used for many types of printing including color printing because noise during printing is relatively low and small dots can be formed with high density.

  Such an ink jet recording apparatus includes an ink jet recording head that receives the supply of ink from the ink storage means, and a paper feeding means that moves the recording paper relative to the recording head, and performs recording according to a print signal. Recording is performed by ejecting ink droplets onto the recording paper while moving the head to form dots.

  A common head holder (carriage) is provided with a recording head that can eject black, yellow, cyan, and magenta inks. In addition to text printing with black ink, full-color printing can be performed by changing the ejection ratio of each ink. It is possible.

  In such an ink jet recording head, printing is performed by ejecting ink pressurized in a pressure generating chamber as ink droplets from a nozzle onto a recording sheet, and therefore, an increase in ink viscosity due to evaporation of a solvent from a nozzle opening or In addition, there is a problem that the nozzle opening is clogged due to solidification of ink, adhesion of dust, and mixing of bubbles, resulting in poor printing.

  For this purpose, the ink jet recording apparatus usually includes a capping device for sealing the nozzle openings of the recording head during non-printing, and a cleaning device for cleaning the nozzle plate as necessary.

  This capping device not only functions as a lid for preventing the ink at the nozzle opening from being dried, but also when the nozzle opening is clogged, the nozzle plate is sealed with a cap member to remove the ink from the suction pump. It also has a function of eliminating the clogging of the nozzle openings by sucking ink from the nozzle openings by the negative pressure.

  The forcible ink ejection process to eliminate clogging of the recording head is usually called a cleaning operation. When printing is resumed after a long pause or when the user clears clogging of the recording head. This process is executed when the cleaning switch is pressed, and includes a wiping operation by a cleaning member made of an elastic plate such as rubber after discharging ink droplets.

  Also, it has a function to eject ink droplets by applying a drive signal unrelated to printing to the recording head, which is usually called a flushing operation, and is uneven in the vicinity of the nozzle opening of the head by wiping or the like during the cleaning operation. This operation is performed at regular intervals for the purpose of recovering the meniscus of the nozzle and preventing clogging of the nozzle opening with less ink droplet ejection during printing.

  23 and 24 show the configuration of a capping device used in a conventional ink jet recording apparatus. Of these, FIG. 23 is a top view, and FIG. 24 is taken along line AA in FIG. FIG.

  23 and 24, the cap unit 38 includes a square-shaped cap case 40 whose upper surface is released, and an elastic member such as rubber, which is housed in the cap case 40 and has ink resistance. And a cup-shaped cap member 16 formed by the above. The cap member 16 is formed such that its upper edge protrudes slightly from the cap case 40.

  Further, an ink absorbing material 17 made of a porous material excellent in ink resistance and ink absorption is accommodated in the inner bottom portion of the cap member 16 so as to have a gap g between the inner surface of the cap member 16. . The ink absorbing material 17 is configured to be held in the cap member 16 by a stopper member 16 a disposed at a part of the cap member 16.

  Further, an ink suction port 18 and an air release port 19 are disposed on the lower bottom portions of the cap case 40 and the cap member 16 so as to penetrate the cap case 40 and the cap member 16. The ink suction port 18 and the air release port 19 are disposed so as to be located at a predetermined interval along the substantially center of the capping device in the longitudinal direction when the capping device is viewed from above.

  Next, FIG. 25 shows a state in which the nozzle plate 14 of the color print recording head 8 is sealed by the cap unit 38 described above. The recording head 8 is located in the upper part of the capping device, and the nozzle plate 14 is capped from below by the capping device. Nozzle openings 15 are arranged in the nozzle plate 14, and each ink of yellow, cyan and magenta is ejected by the action of the piezoelectric vibrator 13 arranged corresponding to each nozzle opening 15. .

  In the above configuration, the ink suction action for eliminating the clogging of the nozzle openings is performed when the cap member 16 is in close contact with the nozzle plate 14 of the recording head 8 as shown in FIG. The suction pump connected to the ink suction port 18 is operated to apply a negative pressure inside the cap.

Then, when the ink is discharged from the nozzle opening 15 and the negative pressure inside the cap is reduced to some extent, the valve connected to the atmosphere opening port 19 is opened to allow the inflow of the atmosphere, and the negative pressure inside the cap member is reduced. All are released.
Related prior art documents include the following.

JP 7-276650 A Japanese Utility Model Publication No. 5-35281 JP-A-9-39258 Japanese Utility Model Publication No. 2-144437

  By the way, the ink discharged from the nozzle opening 15 of the recording head by the ink discharging action described above is absorbed by the ink absorbing material 17 accommodated in the cap member 16. The ink absorbing material 17 is usually formed of a porous material such as sponge. The ink absorbing material 17 gradually swells due to the absorption of the ink, and swells up to fill the gap g described above. As shown, the central portion is deformed to the nozzle plate 14 side, that is, is curved and the central portion is raised. The ink absorbing material 17 has a particularly severe degree of swelling when the recording apparatus is left standing for a long time and then reused, and the deformation action as described above is likely to occur.

  For this reason, a space G is generated between the ink absorbing material 17 and the bottom surface of the cap member 16, and this space G becomes an ink reservoir. Then, when the atmosphere is introduced from the atmosphere opening port 19, a phenomenon occurs in which the ink is bubbled up from the space (ink reservoir) G through the ink absorbing material 17 to the upper part.

  In particular, as shown in FIG. 25, when the central portion of the ink absorbing material 17 is raised to the nozzle plate 14 side, the distance between the ink absorbing material 17 and the nozzle plate 14 of the recording head approaches, and the ink absorption. The ink bubbled at the top of the material 17 immediately adheres to the nozzle plate 14 of the recording head.

  Accordingly, there is a technical problem that ink bubbles enter the nozzle openings 15 to destroy the meniscus of the nozzle openings 15 and cause printing defects such as so-called dot dropout or color mixing.

  The present invention has been made by paying attention to the above-described technical problems, and is configured to ensure sufficient spacing from the nozzle plate even if the ink absorbing material swells, thereby enabling printing due to the influence of foamed ink. An object of the present invention is to provide an ink jet recording apparatus that can effectively prevent the occurrence of defects.

  According to a preferred embodiment of the ink jet recording apparatus according to the present invention made to achieve the above object, an ink jet recording head for ejecting ink droplets from a nozzle opening and the nozzle opening at the time of non-printing are provided. An ink jet recording apparatus that includes a cap member that seals a nozzle plate and sucks ink from the nozzle openings as needed, and is accommodated in the cap member and absorbs ink sucked from the nozzle openings. In the ink absorbing material to be formed, a recess formed by a recess or a notch is formed in a portion facing the nozzle opening.

  According to another preferred embodiment of the ink jet recording apparatus according to the present invention, an ink jet recording head that discharges ink droplets from the nozzle openings and a nozzle plate that includes the nozzle openings are sealed during non-printing. In addition, an ink jet recording apparatus including a cap member that sucks ink from the nozzle openings as needed, and is an ink absorbing material that is accommodated in the cap member and absorbs ink sucked from the nozzle openings. The fixing portion is configured to prevent the portion from being deformed to the nozzle plate side due to swelling due to ink absorption.

  According to still another preferred embodiment of the ink jet recording apparatus according to the present invention, an ink jet recording head that discharges ink droplets from nozzle openings and a nozzle plate that includes the nozzle openings when not printing are sealed. In addition, an ink jet recording apparatus including a cap member that sucks ink from the nozzle opening as necessary, and an opening peripheral edge of the cap member that contains an ink absorbing material that absorbs ink sucked from the nozzle opening In addition, in the state where the bellows portion is formed by a flexible member and the nozzle plate of the recording head is sealed, the gap between the nozzle plate and the ink absorbing material can be increased by the interposition of the bellows portion.

  In this case, it is preferable that a recess such as a recess or a notch is further formed in a portion of the ink absorbing material facing the nozzle opening. Furthermore, a configuration including a fixing means for preventing a part of the ink absorbing material from being deformed to the nozzle plate side by swelling due to ink absorption may be used in combination.

  The fixing means is preferably arranged so as to avoid a position facing the nozzle opening in a state where the cap member seals the nozzle plate of the recording head.

  Further, it is desirable that the fixing means is disposed in the vicinity of the atmosphere opening port opened in the cap member so that the ink absorbing material can be prevented from floating near the atmosphere opening port.

  As a fixing means used for this, a pin member preferably having a hemispherical head or an ink guiding groove on the upper surface of the hemispherical head is used, and its tail is implanted in the cap member, The ink absorbing material is configured to be fixed in the cap member by the head.

  Alternatively, a pin member integrally formed with the cap case is used, and a head portion with an ink guide groove is formed on the hemispherical or hemispherical upper surface by heat-deforming the tip portion, and ink is absorbed by the head at the same time. A material is configured to be secured within the cap member.

  In another preferred form of the fixing means, at least a part of the fixing means is constituted by a frame member that can engage with a side wall of the cap member, and the ink absorbing material is fixed in the cap member by the frame member. Composed.

  Even if a pin member or a frame member is used as the fixing means, it is desirable that these are formed of a metal material having water repellency.

  According to the ink jet recording apparatus configured as described above, even if the ink absorbing material accommodated in the cap member swells and deforms to the nozzle plate side of the recording head, it faces the nozzle opening in the ink absorbing material. Since the depression due to the recess or the notch is formed in the portion to be performed, it is possible to reduce the adverse effect on the nozzle opening due to the bubble of ink generated on the upper surface of the ink absorbing material.

  Further, by adopting a fixing means for preventing the ink absorbing material from being deformed to the nozzle plate side due to swelling of the ink absorbing material accommodated in the cap member, similarly, the ink generated on the upper surface of the ink absorbing material can be reduced. The bad influence to the nozzle opening by a bubble can be reduced.

  Further, by forming the bellows portion by the flexible member around the opening periphery of the cap member, it becomes possible to increase the gap between the nozzle plate and the ink absorbing material by the interposition of the bellows portion, and similarly the ink absorbing material. The adverse effect on the nozzle opening due to the ink bubbles generated on the upper surface of the ink can be reduced.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording apparatus according to the present invention will be described based on an embodiment shown in the drawings. FIG. 1 shows an embodiment of an ink jet recording apparatus to which the present invention is applied. In FIG. 1, reference numeral 1 denotes a carriage, which is guided by a guide member 4 via a timing belt 2 that reciprocates by driving of a carriage motor 3. And is reciprocated in the axial direction of the platen 5.

  A black recording head 7 and a color recording head 8 are mounted on the side of the carriage 1 that faces the recording paper 6, and a black ink cartridge 9 that supplies ink to each recording head is provided above the recording head 8. A color ink cartridge 10 is detachably loaded.

  Reference numeral 11 in the figure denotes a capping device arranged outside the non-printing area, in which a black head cap unit 37 and a color head cap unit 38 are arranged. A suction pump 12 for applying a negative pressure to the capping device 11 is disposed below the capping device 11.

  The cap units 37 and 38 function as cap means for preventing the nozzle opening from being dried during the rest period of the recording apparatus, and also function as ink receivers during the flushing operation, and the negative pressure from the suction pump 12 is applied to the recording head. 7 and 8 is also used as a means for sucking ink.

  FIG. 2 shows an example of an actuator unit in the color recording head 8 described above. Three piezoelectric vibrators 13 are arranged on the nozzle plate 14 and are not shown in FIG. Ink supply channels 20a to 20f are provided for each nozzle opening row between the piezoelectric vibrators 13 and the nozzle plate 14 so that different color inks can be ejected from the nozzle opening rows formed in the nozzle openings. It has been.

  With this configuration, each of the piezoelectric vibrators 13 is supplied with a print control signal, whereby the yellow, cyan, and magenta inks supplied to the ink supply channels 20a to 20f are respectively ejected from the nozzle opening arrays, and the recording paper 6 Is printed in color.

  3 (a) and 3 (b) show the overall configuration of the capping device 11, (b) is a perspective view of the capping device 11 viewed from one direction, and (b) is a view of (b). It is the perspective view seen from the back direction. Reference numeral 22 in the drawing is a slider, which is connected to the base 21 by a freely rotating arm 23 and a spring 31. When the carriage 1 moves to the non-printing area side and comes into contact with the flag piece 25, the carriage It is configured to move following the movement of 1. A valve unit 28 is fixed to the slider 22, and a valve 29 for opening and closing the valve unit 28 is fixed to the base 21 via a compression spring 30.

  The flag piece 25 has a convex piece 26 at the lower end, and is configured to abut against the inclined guide surface 24 formed on the base 21 and slide on the surface thereof. A guide surface 32 is also provided on the side portion on the printing area side, and a protrusion 33 protruding in the horizontal direction on the slider 22 is configured to slide on the surface thereof. By the action of these two guide surfaces 24 and 32, the slider 22 can be moved up and down while maintaining a substantially horizontal posture.

  That is, when the carriage 1 moves to the non-printing area side, the slider 22 moves obliquely upward in conjunction with the movement of the carriage 1, thereby performing a capping operation in which the cap member and the nozzle plate surface of the recording head are in close contact with each other. It is configured as follows.

  The cap unit mounting portion 36 of the slider 22 is connected to the slider 22 by a spring 34 and a protrusion 35, and can be slightly rotated around the protrusion 35. The cap units 37 and 38 are fixed to the slider 22 via compression springs 39, respectively. Therefore, during the capping operation, the adhesion between the cap and the nozzle plate is always kept good.

  Each of the cap units 37 and 38 is formed with an ink suction port 18 at a lower bottom portion thereof, and is connected to the suction pump 12 shown in FIG. 1 through a tube (not shown) having excellent ink resistance. Further, although not shown in FIG. 3, each of the cap units 37 and 38 is provided with an air release port to be described later on its bottom surface, and the other end of the tube 27 having one end connected to the air release port is a valve. Each is connected to a unit 28.

  With the above configuration, when the carriage 1 moves to the non-printing area side, the carriage 1 comes into contact with the flag piece 25 as described above, and as a result, the slider 22 moves obliquely upward, and the cap units 37 and 38 are moved to the recording head. The nozzle plate surface is capped.

  When the slider 22 is positioned on the non-printing area side (home position), the valve unit 28 comes into contact with the valve 29, and the atmosphere opening is closed. In this state, by supplying negative pressure from the suction pump 12 to the inside of the cap, ink can be sucked from the nozzle openings of the recording head.

  Next, FIG. 4 shows the first embodiment of the cap unit 38 for the color head in the above-described capping device as viewed from above. FIG. 5 is a cross-sectional view taken along the line BB in FIG. The parts corresponding to those of the conventional apparatus already described with reference to FIGS. 23 to 25 are denoted by the same reference numerals, and the description thereof is omitted.

  In the first embodiment of the cap unit 38 shown in FIGS. 4 and 5, the upper surface of the ink absorbing material 17 is recessed in the portion facing each nozzle opening 15 of the recording head 8, that is, in the direction of the nozzle row. A cylindrical concave portion 17a is formed so that the axial directions coincide.

  Thus, by forming the concave portion 17a on the upper surface of the ink absorbing material 17, the ink absorbing material 17 absorbs the ink and swells, and even if the central portion is deformed so as to rise to the nozzle plate side, the ink A certain distance between the absorbent 17 and each nozzle opening (nozzle row) 15 of the recording head 8 can be secured. Therefore, even if a phenomenon that ink bubbles blow up due to the opening of the atmosphere opening port 19, the bubbles can be prevented from reaching the nozzle openings 15, or the degree thereof can be reduced.

  Next, the second embodiment shown in FIG. 6 and FIG. 7 can also obtain the same function and effect, and FIG. 7 is shown in a sectional view taken along the line CC in FIG. . Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals.

  In the second embodiment shown in FIG. 6 and FIG. 7, a through hole is formed in the upper ink absorbing material of the ink absorbing material 17 composed of two upper and lower sheets by a notch 17 b. And the through-hole by the notch part 17b is comprised by the rectangular shape, and it is formed so that the longitudinal direction may correspond to the direction of a nozzle row.

  As a result, depressions are formed in portions of the upper surface of the ink absorbing material 17 facing the nozzle openings 15 of the recording head 8. In such a configuration as well, even if a phenomenon that ink bubbles blow up due to the opening of the atmosphere opening port 19 can be prevented, the bubbles can be prevented from reaching the nozzle openings 15 or the degree thereof can be reduced. Is possible.

  Next, the configuration shown in FIG. 8 and FIG. 9 shows a third embodiment. FIG. 9 is a cross-sectional view taken along line DD in FIG. Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals.

  In the third embodiment shown in FIGS. 8 and 9, a part of the ink absorbing material is further deformed to the nozzle plate side by swelling due to ink absorption, as compared with the first embodiment shown in FIGS. Fixing means are provided to prevent this. That is, the central portion of the ink absorbing material 17 is fixed by the two pin members 51 implanted in the cap member 16 so that the center portion of the ink absorbing material 17 is not curved toward the nozzle plate 14 due to swelling due to ink absorption.

  The pin member 51 penetrates the ink absorbing material 17 and is fixed so that the ink absorbing material 17 is fixed in the cap member 16 by a head 51a by implanting a tail portion of the pin member 51 in the cap member 16. The two pin members 51 are arranged so as to avoid a position facing the nozzle openings 15 in a state where the cap member 16 seals the nozzle plate 14 of the recording head.

  That is, as shown in FIG. 9, the two pin members 51 are arranged so as to be positioned between the nozzle rows, avoiding directly below the nozzle rows, respectively. This acts to prevent the nozzle opening from being adversely affected during ink suction.

  The pin member 51 is disposed in the vicinity of the atmosphere opening port 19 opened in the cap member 16, and is particularly configured to prevent the ink absorbing material 17 from being lifted in the vicinity of the atmosphere opening port 19. As a result, it is possible to effectively reduce the degree of generation of ink bubbles caused by a gap with the ink absorbing material in the vicinity of the air opening 19.

  Next, the configuration shown in FIG. 10 and FIG. 11 shows a fourth embodiment. FIG. 11 is a cross-sectional view taken along line EE in FIG. Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals. 10 and 11, in the fourth embodiment shown in FIGS. 6 and 7, a part of the ink absorbing material is further deformed to the nozzle plate side by swelling due to ink absorption. This is provided with a pin member 51 that prevents this.

  As described above, in the state where the cap member 16 seals the nozzle plate 14 of the recording head, the pin member 51 is arranged so that the pin member 51 is positioned between the nozzle rows while avoiding the position immediately below the nozzle rows. In addition, it is desirable that the air outlet 19 is disposed in the vicinity.

  In the third and fourth embodiments described above, even if the ink absorbing material 17 absorbs ink and swells, the center portion thereof is curved toward the nozzle plate 14 due to the presence of the pin member 51 as a fixing means. There is nothing. In addition, by forming recesses 17 a or notches 17 b on the upper surface of the ink absorbing material 17, it is possible to ensure a considerable distance between the ink absorbing material 17 and each nozzle opening 15 of the recording head 8. Therefore, even if a phenomenon that ink bubbles blow up due to the opening of the atmosphere opening port 19, the bubbles can be prevented from reaching the nozzle openings 15, or the degree thereof can be further reduced.

  In the third and fourth embodiments described above, the ink absorbing material 17 in which the concave portion 17a or the cutout portion 17b is intentionally formed is fixed by the pin member 51. However, the concave portion 17a or the cutout portion is used. Even if the ink absorbing material 17 having a flat upper surface not provided with 17b is employed, the presence of the pin member 51 as the fixing means prevents the ink absorbing material 17 from being bent toward the nozzle plate 14 due to swelling. Therefore, a sufficient interval between the nozzle plate 14 and the ink absorbing material 17 can be secured, and ink bubbles can be effectively prevented from reaching the nozzle openings 15.

  The configuration shown in FIG. 12 and FIG. 13 shows the fifth embodiment. Parts corresponding to those of the conventional apparatus already described with reference to FIGS. 23 to 25 are denoted by the same reference numerals. In the third and fourth embodiments described above, the ink absorbing material 17 is fixed in the cap member by implanting the pin member 51 in the cap member 16, but in the fifth embodiment, As shown in FIG. 12, the pin member 51 has a rod shape and is integrally formed with the cap case 40.

  As shown in FIG. 13A, the pin member 51 has a structure that penetrates the cap member 16 and the ink absorbing material 17 and has a tip portion protruding upward from the absorbing material 17. Then, the tip end portion is heated and crushed, whereby the ink absorbing material 17 is caulked and fixed in the cap member as shown in FIG. 13B.

  In the fifth embodiment shown in FIG. 12, the ink absorbing material 17 having a flat upper surface is adopted. However, since it is caulked and fixed by the five pin members 51, the ink absorbing material 17 It is configured to reliably prevent lifting due to swelling. Thereby, the bad influence to the nozzle opening by the bubble of the ink which generate | occur | produces on the upper surface of an ink absorber can be reduced effectively.

  Further, in the present embodiment, the same effect can be obtained even when the ink absorbing material 17 provided with the concave portion 17a or the notch portion 17b is employed instead of the ink absorbing material 17 having a flat upper surface. Is clear.

  FIG. 14 shows various external configurations of the pin member 51 described above. That is, the pin member shown in FIG. 12A is used in the capping device shown in FIGS. 8 to 13 described above, and the upper surface of the head portion 51a is made flat. is there. In the pin member shown in FIG. 14A, since the upper surface of the head 51a is flat, the ink is placed on the upper surface by the surface tension of the ink, and the ink is discharged from the capping device. Even later, there is a problem that ink remains.

  Therefore, it is preferable to form the head 51a of the pin member 51 in a hemispherical shape as shown in FIG. By forming the pin member head in a hemispherical shape in this way, it is possible to reduce the phenomenon that ink remains on the head portion 51a of the pin member 51 due to surface tension, and the ink around the pin member 51 is placed on the ink absorbing material 17 side. Absorbed.

  Further, as shown in FIGS. 14C and 14D, the head 51a of the pin member 51 is formed in a hemispherical shape, and an ink guide groove 51b is further formed on the upper surface of the hemispherical head. More preferably. FIGS. 14C and 14D show the pin member 51 as viewed from the front and side directions orthogonal to each other. One groove 51b is formed at the center of the upper surface of the hemispherical head. It has been subjected. By providing the ink guide groove 51b in this way, the ink passes through the guide groove and is immediately absorbed on the ink absorbing material 17 side. The number of ink guide grooves 51b is not limited to one as shown in the figure, and an appropriate number is provided according to the size of the hemispherical head. In this case, the ink guide grooves may be arranged so as to cross.

  Furthermore, in the third and fourth embodiments in which the pin member 51 is implanted in the cap member 16, any of the pin members 51 shown in FIG. 14 has water repellency such as stainless steel. By using the metal material, an effect of further reducing the residual degree of ink can be obtained.

  By using the various pin members described above, there is no need to provide the gap g between the inner surface of the cap member 16 and the ink absorbing material 17 unlike the conventional one already described in FIG. That is, it is possible to eliminate the cause of ink bubbles caused by providing the gap g, and it is possible to increase the reliability of the print head cleaning process.

  Next, the configuration shown in FIGS. 15 and 16 is a cross-sectional view of the sixth embodiment. FIG. 1515 shows a state in which the capping device is separated from the nozzle plate 14, and FIG. Indicates a state in which the capping device is in contact with the nozzle plate 14. Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals.

  In the sixth embodiment, a bellows portion 16a made of a flexible member is formed on the periphery of the opening of the cap member 16 so as to face upward. That is, the bellows portion 16a is formed to be slightly thin integrally with the cap member 16, and the cross section orthogonal to the extending direction is formed in a “<” shape.

  In such a configuration, the cap member 16 is in close contact with the nozzle plate 14 by the above-described capping operation. At the time of ink suction, a negative pressure is generated inside the cap in this state, so that the bellows portion 16a of the cap member contracts as shown in FIG. 15, and the nozzle plate 14 and the ink absorbing material 17 approach each other. For this reason, it becomes possible to efficiently absorb the ink that has oozed out on the nozzle plate surface.

  On the other hand, when the suction of the ink is completed and the inside of the cap is opened to the atmosphere, the negative pressure inside the cap is released and simultaneously the contraction of the bellows portion 16a is recovered. The interval of becomes sufficiently wide. Thereby, it is possible to effectively prevent the foamy ink generated when the atmosphere is released from adhering to the nozzle opening 15.

  In the sixth embodiment, the surface of the ink absorbing material 17 is flat. However, as in the first to fourth embodiments already described, the surface of the ink absorbing material 17 is used. You may form the recessed part 17a and the notch part 17b in this. In this case, the gap between the ink absorbing material 17 and the nozzle opening 15 can be formed larger.

  Further, as in the third and fourth embodiments described above, a plurality of portions excluding the concave portion 17a or the notch portion 17b are provided so that the central portion of the ink absorbing material 17 is not curved toward the nozzle plate 14 side. It may be fixed by the pin member 51.

  Also in this case, the pin member 51 is arranged between the nozzle rows while avoiding the position immediately below each nozzle row in the state where the cap member 16 seals the nozzle plate 14 of the recording head as described above. It is desirable to arrange so that it is located in the vicinity of the atmosphere opening 19.

  Next, the configuration shown in FIG. 17 and FIG. 18 shows a seventh embodiment. FIG. 17 is a sectional view taken along line FF in FIG. Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals. In the seventh embodiment shown in FIGS. 17 and 18, a frame member 52 that can be engaged at least partially with the side wall of the cap member 16 is used as the fixing means. The ink absorbing member 17 is pressed from the upper surface side by the frame member 52 to fix the ink absorbing member 17 in the cap member 16.

  The frame member 52 is formed in a quadrangular shape so as to be inscribed in the cap member 16, and is configured to be engaged with the side wall of the cap member 16 on the entire peripheral edge thereof. And a pair of beam part 52a is integrally formed so that a longitudinal direction may be divided into three. With this configuration, even if the ink absorbing material 17 absorbs ink and swells, the presence of the frame member 52 as the fixing means effectively prevents the central portion from being bent toward the nozzle plate 14 side.

  In addition, in the state where the cap member 16 seals the nozzle plate 14 of the recording head, the beam portion 52a avoids a position directly below each nozzle row in the state where the cap member 16 seals the nozzle plate 14 of the recording head. It is formed so as to be located between them.

  The frame member 52 is also made of a metal material having water repellency such as stainless steel as in the case of the pin member described above, thereby reducing the amount of ink remaining on the upper surface. Can do.

  The configuration shown in FIGS. 19 and 20 shows the eighth embodiment, and FIG. 19 is a cross-sectional view taken along the line GG in FIG. Portions corresponding to the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals. In the eighth embodiment, in addition to the embodiment shown in FIGS. 18 and 19, the upper surface of the ink absorbing material 17 is recessed in the portion facing each nozzle opening 15 of the recording head 8, that is, the direction of the nozzle row. A cylindrical concave portion 17a is formed so that the axial directions thereof coincide with each other. As a result, the same operational effects as those of the first embodiment shown in FIGS. 4 and 5 can be obtained.

  Furthermore, the configuration shown in FIGS. 21 and 22 shows the ninth embodiment, and FIG. 21 is a cross-sectional view taken along the line HH in FIG. Parts corresponding to those of the conventional apparatus already described in FIGS. 23 to 25 are denoted by the same reference numerals. In the ninth embodiment, in addition to the embodiment shown in FIGS. 18 and 19, a through hole formed by a notch portion 17b is provided in the upper ink absorbing material of the ink absorbing material 17 further composed of two upper and lower sheets. The example which formed is shown. Thereby, the same effect as the second embodiment shown in FIGS. 6 and 7 can be obtained.

  Note that the frame member 52 used in FIGS. 17 to 20 is formed by processing means such as punching a thin plate material, but the frame member 52 is formed by a wire-like shape instead. Also good.

  Thus, even if a frame member formed by punching or wire-like is used, it is necessary to provide a gap g between the inner surface of the cap member 16 and the ink absorbing material 17 as shown in FIG. Disappear. Accordingly, it is possible to eliminate the cause of ink bubbles due to the provision of the gap g, and it is possible to increase the reliability of the print head cleaning process.

As is apparent from the above description, the ink jet recording apparatus according to the present invention has a recess formed by a recess or a notch in the portion of the ink absorbing material facing the nozzle opening of the recording head. It is possible to prevent or reduce the extent that ink bubbles are generated when the ink is opened and reach the nozzle opening. As a result, it is possible to effectively avoid the problem of causing a printing failure such as so-called dot omission by destroying the meniscus of the nozzle opening due to ink bubbles entering the nozzle opening.
In addition, since the fixing means for preventing a part of the ink absorbing material from being deformed to the nozzle plate side due to the swelling due to the absorption of the ink is provided, a phenomenon that the central portion of the ink absorbing material is raised can be prevented. Accordingly, it is possible to reduce the occurrence of printing troubles due to ink bubbles or their scattering.

  In addition, since the fixing means for preventing a part of the ink absorbing material from being deformed to the nozzle plate side due to the swelling due to the absorption of the ink is provided, a phenomenon that the central portion of the ink absorbing material is raised can be prevented. Accordingly, it is possible to reduce the occurrence of printing troubles due to ink bubbles or their scattering.

  Further, by forming the bellows portion by the flexible member around the opening periphery of the cap member, it is possible to increase the interval between the nozzle plate and the ink absorbing material by the intervention of the bellows portion. It is possible to reduce the occurrence of printing troubles due to the bubbles or their scattering.

1 is a perspective view of an ink jet recording apparatus to which the present invention is applied. FIG. 2 is a perspective view illustrating an example of an actuator unit in a recording head mounted on the recording apparatus illustrated in FIG. 1. It is a perspective view which shows an example of the capping apparatus mounted in the recording device shown in FIG. 1 is a top view showing a first embodiment of a cap unit mounted on a recording apparatus according to the present invention. FIG. It is sectional drawing of the state cut | disconnected by the BB line in FIG. It is the top view which showed 2nd Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the CC line | wire in FIG. It is the top view which showed 3rd Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the DD line | wire in FIG. It is the top view which showed 4th Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the EE line | wire in FIG. It is the perspective view which showed 5th Embodiment of the cap unit. It is sectional drawing of the state which cut | disconnected the pin member part in FIG. 12 perpendicularly | vertically. It is the figure which showed each structure of the pin member as a fixing means. It is the center sectional view showing a 6th embodiment of a cap unit. It is a center sectional view showing the state where the cap unit was also in pressure contact with the nozzle plate. It is the top view which showed 7th Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the FF line | wire in FIG. It is the top view which showed 8th Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the GG line in FIG. It is the top view which showed 9th Embodiment of the cap unit. It is sectional drawing of the state cut | disconnected by the HH line | wire in FIG. It is the top view which showed the example of the conventional cap unit. It is sectional drawing of the state cut | disconnected by the AA in FIG. It is a center sectional view showing a state where an ink absorbing material swells in a conventional cap unit.

Explanation of symbols

7 Black recording head, 8 Color recording head, 9 Black ink cartridge, 10 Color ink cartridge, 11 Capping device, 12 Suction pump, 14 Nozzle plate, 15 Nozzle opening, 16 Cap member, 16a Bellows, 17 Ink Absorbent, 17a Concave part (dent), 17b Notch part (dent), 18 Ink suction port, 19 Air release port, 36 Cap unit mounting part, 37 Black head cap unit, 38 Color head cap unit, 40 Cap case , 51 Pin member (fixing means), 52 Frame member (fixing means)

Claims (4)

Inkjet recording head that ejects ink droplets from nozzle openings, and an ink jet recording apparatus that includes a cap member that seals the nozzle plate having the nozzle openings when not printing, and discharges ink from the nozzle openings as necessary. A recording device,
A fixing unit that is housed in the cap member and that prevents a part of the ink absorbing material that absorbs the ink discharged from the nozzle opening from being deformed to the nozzle plate side;
The fixing means uses a pin member having a hemispherical head or an ink guide groove on the upper surface of the hemispherical head, and by implanting a tail portion of the pin member on the cap member, An ink jet recording apparatus configured to be fixed in a cap member by a head. 2. The ink jet recording apparatus according to claim 1, wherein the fixing means is made of a metal material having water repellency. Inkjet recording head that ejects ink droplets from nozzle openings, and an ink jet recording apparatus that includes a cap member that seals the nozzle plate having the nozzle openings when not printing, and discharges ink from the nozzle openings as necessary. A recording device,
A fixing unit that is housed in the cap member and that prevents a part of the ink absorbing material that absorbs the ink discharged from the nozzle opening from being deformed to the nozzle plate side;
The fixing means uses a pin member that is integrally formed with the cap case and has a structure in which the tip portion protrudes upward from the ink absorbing material, and the ink absorbing material is heated and crushed by the pin portion. An ink jet recording apparatus characterized in that the ink jet recording apparatus is fixed in the cap member. Inkjet recording head that ejects ink droplets from nozzle openings, and an ink jet recording apparatus that includes a cap member that seals the nozzle plate having the nozzle openings when not printing, and discharges ink from the nozzle openings as necessary. A recording device,
A fixing unit that is housed in the cap member and that prevents a part of the ink absorbing material that absorbs the ink discharged from the nozzle opening from being deformed to the nozzle plate side;
As the fixing means, a pin member integrally formed with the cap case is used, and a head portion with an ink guide groove is formed on the hemispherical or hemispherical upper surface by heat-deforming the tip portion, and at the same time, the head An ink jet type recording apparatus, wherein the ink absorbing material is fixed in the cap member by the portion.

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