JP2006231742A - Inkjet recorder and method of suction for recovery using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recorder that can efficiently discharge foreign matter in a recording head attached to the inkjet recorder by a normal suction operation for recovery even when defective ejection due to foreign matter such as dust occurs on the recording head, and a method of suction for recovery of a recording head using the inkjet recorder. <P>SOLUTION: A plurality of ejection nozzles on a recording element substrate are constituted of an ejection nozzle group for the ejection nozzles each having a large opening area and an ejection nozzle group for the ejection nozzles each having a small opening area. The inkjet recorder comprises a recovery means that independently discharges ink from each of the different groups. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording apparatus using an ink jet recording head that discharges ink, and an ink jet recording apparatus that performs discharge recovery processing to recover when an ink discharge port is clogged, and a recovery method. is there.

  Conventionally, an image is recorded by selectively ejecting ink droplets from a plurality of ink ejection ports formed in an ink jet recording head based on recording data and attaching the ink droplets to a recording surface of a recording medium. Inkjet recording apparatuses are in practical use. In such an ink jet recording apparatus, the serial scan type has a configuration in which an ink jet recording head is mounted on a carriage portion that is moved in the main scanning direction that intersects the conveyance direction (sub scanning direction) of the recording medium. ing.

  In the inkjet recording head, for example, a drive control signal is supplied to each heating resistance element in the recording element substrate through a printed wiring board. When the heating resistance element generates heat according to the drive control signal, the ink is heated to generate bubbles due to the film boiling phenomenon, and is ejected as ink droplets from the ink ejection port as the bubbles expand. The ejected ink droplets land on the recording medium to form an image.

  In such an ink jet recording apparatus, discharge recovery for preventing and recovering ink discharge failure based on clogging due to intrusion of bubbles in the discharge port of the print head, contamination of foreign matter into the ink flow path of the print head, etc. Means have been adopted so far.

  If bubbles enter the discharge port of the recording head or the common liquid chamber, or if foreign matter enters the ink flow path of the recording head, the recording head cannot perform stable and normal recording operations. End up. Therefore, in the suction recovery method, for example, the suction cap seal rubber connected to the suction pump via the ink discharge tube is brought into contact with the outer region of the recording discharge port on the discharge port surface of the recording head and then sucked. The pump is driven, the air pressure in the sealed space between the suction cap and the ejection port surface of the recording head is set to a negative pressure state equal to or lower than the atmospheric pressure, the ink is sucked and discharged from the ejection port of the recording head, and collected into the waste ink tank The recording head discharge recovery process is performed.

As another conventional example, Patent Literature 1 and Patent Literature 2 can be cited.
Japanese Patent Laid-Open No. 06-206320 JP 08-281972 A

  By the way, in the ink jet recording apparatus using the recording head as described above, in recent years, the demand for high-quality and high-definition recording comparable to silver halide photography has been increasing. Therefore, for example, in order to improve the recording quality, the recording density and the size of the recording droplet are rapidly increasing. Along with this, the arrangement density of the nozzles for discharging the recording liquid is increased, and the opening area of the discharge ports for discharging the recording liquid tends to be extremely small. In addition, since there is a demand for improvement in recording speed, in order to achieve high image quality and high speed at the same time, an ejection opening with a large opening area and an ejection opening with a small opening area are arranged in one recording element substrate. A recording head is provided.

  For these reasons, there is an increased probability that foreign matter such as dust will enter the discharge port, especially the discharge port with a small opening area, and printing defects are likely to occur. In some cases, foreign matter such as dust is clogged and printing failure occurs.

  Therefore, in the present invention, even if a discharge failure due to foreign matter such as dust occurs in the recording head mounted on the ink jet recording apparatus, the ink jet recording that can efficiently discharge the foreign matter in the recording head by a normal suction recovery operation. An apparatus and a method for sucking and recovering a recording head using the same are provided.

  In order to solve the above-described problems, an inkjet recording apparatus of the present invention includes a plurality of ejection openings, and includes a recording element substrate having an ink supply path that supplies ink to the plurality of ejection openings. The discharge port is composed of a discharge port group having a large opening area and a discharge port group having a small opening area, and suction recovery is performed to individually discharge ink from each of the discharge port group having a large opening area and the discharge port group having a small opening area. It has the means.

  Further, in the ink jet recording apparatus of the present invention, the discharge port group having the large opening area is disposed at an end portion in the arrangement direction of the discharge port group having the small opening area, and the discharge ports of the discharge port group having the large opening area are It has a printing element substrate which is a dummy discharge port that does not contribute to printing.

  Furthermore, the ink jet recording apparatus of the present invention includes a recording element substrate in which the discharge port group having a large opening area and the discharge port group having a small opening area are arranged to face each other.

  Further, the ink jet recording apparatus of the present invention is characterized by having a non-ejection detecting means for the recording element substrate.

  The suction recovery method of the present invention is characterized in that, in the ink jet recording apparatus, the discharge port group having a large opening area is recovered before the discharge port group having a small opening area.

  The suction recovery method of the present invention is characterized in that when the discharge port group having a large opening area is recovered, the discharge port group having a small opening area is opened to the atmosphere.

  Furthermore, the suction recovery method according to the present invention provides an ink jet recording apparatus having a recording element substrate in which the discharge port groups having a large opening area are arranged at both ends in the arrangement direction of the discharge port groups having a small opening area. It is characterized by alternately recovering from the discharge port group having a large area.

  The suction recovery method according to the present invention is an inkjet recording apparatus having a recording element substrate in which the discharge port group having a large opening area and the discharge port group having a small opening area are arranged to face each other. When recovering from the above, the other discharge port group is blocked by the outer edge of the cap.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIGS. 1 to 6 and FIG. 19 are explanatory diagrams for explaining each of the preferred head cartridge, recording head, and ink tank and the relationship thereof to which the present invention is implemented or applied. Hereinafter, each component will be described with reference to these drawings.

  As can be seen from the perspective views of FIGS. 19 and 4, the recording head H1001 of the present invention is one component constituting the recording head cartridge H1000. The recording head cartridge H1000 is detachable from the recording head H1001 and the recording head H1001. And an ink tank H1900 (H1901, H1902, H1903, H1904) provided in The recording head cartridge H1000 is fixedly supported by positioning means and electrical contacts of a carriage M4001 (not shown) mounted on the ink jet recording apparatus main body, and is detachable from the carriage M4001. The ink tank H1901 is for black ink, the ink tank H1902 is for cyan ink, the ink tank H1903 is for magenta ink, and the ink tank H1904 is for yellow ink. In this way, each of the ink tanks H1901, H1902, H1903, and H1904 is detachable from the recording head H1001, and each ink tank can be replaced, thereby reducing the running cost of printing in the ink jet recording apparatus. The

  Next, the recording head H1001 will be described in detail for each component constituting the recording head.

(1) Recording Head The recording head H1001 is a bubble jet (registered trademark) side that performs recording using an electrothermal transducer that generates thermal energy for causing film boiling of ink in response to an electrical signal. This is a recording head that is of a shooter type.

  As shown in the exploded perspective view of FIG. 2, the recording head H1001 includes a recording element unit H1002, an ink supply unit H1003, and a tank holder H2000.

  Further, as shown in the exploded perspective view of FIG. 3, the recording element unit H1002 includes a first recording element substrate H1100, a second recording element substrate H1101, a first plate H1200, an electrical wiring tape H1300, and an electrical contact substrate H2200. The ink supply unit H1003 is composed of an ink supply member H1500, a flow path forming member H1600, a joint rubber H2300, a filter H1700, and a seal rubber H1800.

(1-1) Recording Element Unit FIGS. 1 and 9 are a perspective view for explaining the configuration of the first recording element substrate H1100 and a sectional view in the direction of arrow AA. The first recording element substrate H1100 is, for example, an anisotropic etching in which an ink supply path H1102 including a long groove-like through-hole as an ink flow path is formed on a Si substrate having a thickness of 0.5 to 1 mm using the crystal orientation of Si. The electrothermal conversion elements H1103 are formed by a method such as sand blasting and arranged on both sides of the ink supply path H1102 respectively, and the electrothermal conversion elements H1103, Al for supplying electric power to the electrothermal conversion elements H1103, etc. The electrical wiring is formed by a film forming technique. Furthermore, electrode portions H1104 for supplying electric power to the electric wiring are arranged on both outer sides of the electrothermal transducer H1103, and bumps H1105 such as Au are formed on the electrode portion H1104. On the Si substrate, an ink channel wall H1106 and an ejection port H3001 for forming an ink channel corresponding to the electrothermal conversion element H1103 are formed of a resin material by a photolithography technique, and an ejection port group H3001- A is formed. Accordingly, since the ejection port is provided to face the electrothermal conversion element H1103, the ink supplied from the ink flow path H1102 is ejected by bubbles generated by the electrothermal conversion element H1103.

  FIG. 5 is a partially exploded perspective view for explaining the configuration of the second recording element substrate H1101. The second recording element substrate H1101 is a recording element substrate for ejecting ink of three colors, and three ink supply paths H1102 are formed in parallel, and electric is provided on both sides of each ink supply path. A heat conversion element and an ink discharge port are formed. Of course, like the first recording element substrate H1100, an ink supply path, an electrothermal conversion element, an electrical wiring, an electrode portion, and the like are formed on the Si substrate, and an ink flow path and an ink discharge are formed on the resin material by photolithography. An exit is formed.

  Similarly to the first recording element substrate, a bump H1105 such as Au is formed on the electrode portion H1104 for supplying electric power to the electric wiring.

Next, the first plate H1200 is made of, for example, an alumina (Al ₂ O ₃ ) material having a thickness of 0.5 to 10 mm. The material of the first plate is not limited to alumina, but has a linear expansion coefficient equivalent to that of the material of the recording element substrate H1100 and is equivalent to the thermal conductivity of the material of the recording element substrate H1100. Alternatively, it may be made of a material having an equivalent or higher thermal conductivity. Examples of the material of the first plate H1200 include silicon (Si), aluminum nitride (AlN), zirconia, silicon nitride (Si ₃ N ₄ ), silicon carbide (SiC), molybdenum (Mo), and tungsten (W). Either may be sufficient. In order to supply, for example, cyan, magenta, and yellow ink to the first plate H1200, an ink supply path H1201 for supplying, for example, black ink to the first recording element substrate H1100 and a second recording element substrate H1101. Ink supply paths H1201 are formed, the ink supply paths 1102 of the recording element substrate correspond to the ink supply paths H1201 of the first plate H1200, respectively, and the first recording element substrate H1100 and the second recording element. Each of the substrates H1101 is bonded and fixed to the first plate H1200 with high positional accuracy. The first adhesive H1202 used for bonding is desirably a low viscosity, low curing temperature, cured in a short time, has a relatively high hardness after curing, and has ink resistance. The first adhesive H1202 is, for example, a thermosetting adhesive mainly composed of an epoxy resin, and the thickness of the adhesive layer is desirably 50 μm or less.

  The electrical wiring tape H1300 applies an electrical signal for ejecting ink to the first recording element substrate H1100 and the second recording element substrate H1101, and includes a plurality of recording element substrates. An electrical contact substrate having an opening, an electrode terminal H1302 corresponding to the electrode portion H1104 of each recording element substrate, and an external signal input terminal H1301 located at the end of the wiring tape for receiving an electrical signal from the main unit An electrode terminal portion H1303 for electrical connection with H2200 is provided, and the electrode terminal H1302 and the electrode terminal 1303 are connected by a continuous copper foil wiring pattern.

  The electrical wiring tape H1300, the first recording element substrate 1100, and the second recording element substrate H1101 are electrically connected to each other, and the connection method is, for example, the electrode portion 1104 of the recording element substrate and the electrical wiring tape H1300. The electrode terminal H1302 is electrically bonded by a thermal ultrasonic pressure bonding method.

The second plate H1400 is, for example, a single plate-like member having a thickness of 0.5 to 1 mm, and is formed of a ceramic material such as alumina (Al ₂ O ₃ ) or a metal material such as Al or SUS. Yes. The first recording element substrate H1100 and the second recording element substrate H1101 that are bonded and fixed to the first plate H1200 have openings that are larger than the outer dimensions thereof. Further, the first recording element substrate H1100 and the second recording element substrate H1101 and the electric wiring tape H1300 are bonded to the first plate H1200 with a second adhesive H1203 so as to be electrically connected in a plane. The back surface of the wiring tape H1300 is bonded and fixed with a third adhesive H1306.

  Electrical connection portions of the first recording element substrate H1100 and the second recording element substrate H1101 and the electric wiring tape H1300 are sealed with a first sealant H1307 (not shown) and a second sealant H1308. Protects electrical connections from ink corrosion and external impacts. The first sealing agent mainly seals the back surface side of the connection portion between the electrode terminal H1302 of the electric wiring tape and the electrode portion H1104 of the recording element substrate and the outer peripheral portion of the recording element substrate, and the second sealing agent. Seals the front side of the connecting part.

  Further, an electrical contact substrate H2200 having an external signal input terminal H1301 for receiving an electrical signal from the main unit is connected to the end of the electrical wiring tape by thermocompression bonding using an anisotropic conductive film or the like.

  The electric wiring tape H1300 is bent at one side surface of the first plate H1200, and is bonded to the side surface of the first plate H1200 with the third adhesive H1306. As the third adhesive H1306, for example, a thermosetting adhesive having a thickness of 10 to 100 μm mainly composed of an epoxy resin is used.

(1-2) Ink Supply Unit The ink supply member H1500 is formed by resin molding, for example. As the resin material, it is desirable to use a resin material mixed with 5 to 40% of glass filler in order to improve the shape rigidity.

As shown in FIGS. 3 and 6, the ink supply member H1500 is one component of the ink supply unit H1003 for guiding ink from the ink tank H1900 to the recording element unit H1002, and the flow path forming member H1600 is ultrasonically welded. As a result, an ink flow path H1501 is formed. Further, a filter H1700 for preventing dust from entering from the outside is joined to the joint H1517 engaged with the ink tank H1900 by welding. Further, in order to prevent ink from evaporating from the joint H1517, A seal rubber H1800 is attached.
The ink supply member H1500 also has a part of the function of holding the removable ink tank H1900, and has a first hole H1503 for engaging the second claw H1910 of the ink tank H1900.

  Also, a mounting guide H1601 for guiding the recording head cartridge H1000 to the mounting position on the carriage M4001 of the ink jet recording apparatus main body, an engaging portion H1508 for mounting and fixing the recording head cartridge to the carriage M4001 by a head set lever, and the carriage M4001. Abutting portion H1509 in the X direction (carriage scanning direction), abutting portion H1510 in the Y direction (recording medium conveyance direction), and abutting portion H1511 in the Z direction (ink ejection direction) for positioning at a predetermined mounting position. I have. In addition, a terminal fixing portion H1512 for positioning and fixing the electrical contact substrate H2200 of the recording element unit H1002 is provided, and a plurality of ribs are provided around the terminal fixing portion H1512 to increase the rigidity of the surface having the terminal fixing portion H1512. ing.

(1-3) Coupling of recording head unit and ink supply unit As shown in FIG. 2 described above, the recording head H1001 is completed by coupling the recording element unit H1002 to the ink supply unit H1003 and further to the tank holder H2000. To do. The coupling is performed as follows.

  The ink supply path of the recording element unit H1002 (ink supply path H1201 of the first plate H1200) and the ink supply path of the ink supply unit H1003 (ink supply path H1601 of the flow path forming member H1600) are communicated so that ink does not leak. Therefore, each member is fixed with the screw H2400 so as to be pressure-bonded via the joint rubber H2300. At the same time, the recording element unit H1002 is accurately positioned and fixed with respect to the reference positions in the X, Y, and Z directions of the ink supply unit.

  The electrical contact substrate H1301 of the recording element unit H1002 is positioned and fixed to one side surface of the ink supply member H1500 by terminal positioning pins H1515 (2 places) and terminal positioning holes H1309 (2 places). The fixing method is, for example, fixed by crimping the terminal coupling pin H1515 provided in the ink supply member H1500, but may be fixed using other fixing means. The completed drawing is shown in FIG.

  Further, the recording head H1001 is completed by fitting the coupling hole and coupling portion of the ink supply member H1500 with the tank holder into the tank holder H2000 and coupling them.

  A completed drawing is shown in FIG.

(2) Description of Print Head Cartridge FIGS. 19 and 4 described above are diagrams for explaining mounting of the print head H1001 and the ink tanks H1901, H1902, H1903, and H1904 constituting the printhead cartridge H1000. Corresponding color inks are stored inside H1902, H1903, and H1904. As shown in FIG. 6, each ink tank is provided with an ink supply path H1907 for supplying ink in the ink tank to the recording head H1001. For example, when the ink tank 1901H is attached to the recording head H1001, the ink supply path H1907 of the ink tank H1901 is brought into pressure contact with the filter H1700 provided in the joint portion H1520 of the recording head H1001, and the black ink in the ink tank H1901 is supplied with ink. The ink is supplied from the path H1907 to the first recording element substrate through the first plate H1200 through the ink flow path H1501 of the recording head H1001.

  Then, ink is supplied to the foaming chamber H1109 having the electrothermal conversion element H1103 and the discharge port H1107, and is ejected toward a recording sheet as a recording medium by the thermal energy given to the electrothermal conversion element H1103.

  FIG. 1 is a perspective view showing an outline of the recording element substrate H1100 used in this embodiment. A plurality of ejection openings H3001 having a small opening area are arranged at positions facing each other across the ink supply path H1102, forming an ejection opening group H3001-A having a small opening area. On the other hand, a plurality of ejection openings H3002 having a large opening area are also arranged so as to face each other across the ink supply path H1102, thereby forming ejection opening groups H3002-A and H3002-B having a large opening area. The discharge port groups H3002-A and H3002-B having a large opening area are arranged at both ends of the arrangement of the discharge port group H3001-A having a small opening area. In this embodiment, the discharge port groups H3002-A and H3002-B having a large opening area are dummy discharge ports that are not directly used for recording on a recording medium. The plurality of ejection openings are arranged in a staggered manner with an ink supply path interposed in a direction in which the recording head is scanned during printing. In this embodiment, ink is supplied from one ink supply path H1102 of the recording element substrate H1100 to both the discharge port groups H3002-A and H3002-B having a large opening area and the discharge port group H3001-A having a small opening area. Is configured to supply. FIG. 9 is a cross-sectional view of the recording element substrate H1100 indicated by arrows AA in FIG.

  FIG. 10 shows a cap H3100 provided as a part of the suction recovery means of the recording head H1001 of the ink jet recording apparatus. The cap H3100 is configured to seal the periphery of each discharge port group. The inside of the cap H3100 is partitioned into three spaces H3101, H3102-A, and H3102-B so as to correspond to the discharge port group H3001-A having a small opening area and the discharge port groups H3002-A and H3002-B having a large opening area. Independent spaces are formed. The cap is generally made of butyl rubber or another suitable material having elasticity. Suction passages H3103, H3104, and H3105 connected to the suction pump are provided inside the caps that cover the respective discharge port groups. Through these suction pumps and suction paths, suction force can be applied independently to the spaces H3101, H3102-A and H3102-B partitioned inside the cap H3100. In this case, a suction pump may be provided for each suction path, or a valve is provided in each of a plurality of suction paths connected to the suction pump so that suction force is applied to each space partitioned inside the cap H3100. May be. In the present embodiment, the cap is formed integrally and has a shape as shown in FIG. 10 in which a partition is provided between each discharge port group. However, the cap is a separate cap arranged so as to be adjacent to each other. There may be.

  In this embodiment, when it is necessary to recover the suction of the recording head H1001, the cap H3100 covers the surface of the recording element substrate H1100 outside the recording area where there is no recording medium, and the cap is closed. FIG. 11A shows a recording head when ink is discharged from the ejection port groups H3002-A and H3002-B having a large opening area in a state where the cap H3100 covers the surface of the recording element substrate H1100 and the cap is closed. A side sectional view of H1001 is shown. In this state, the suction pumps P1, P2, and P3 are operated to apply a suction force to the space spaces H3101, H3102-A, and H3102-B partitioned within the cap H3100.

  When performing the suction recovery operation, suction is performed from the discharge port groups H3002-A and H3002-B having a large opening area prior to the recovery of the discharge port group H3001-A having a small opening area. This is because foreign matters floating in the ink supply path H1102 or dust that floats around the ejection port group H3001-A having a small opening area and clogs the ejection ports H3001 having a small opening area during the recovery operation. This is because the foreign matters such as the above are recovered from the ejection port groups H3002-A and H3002-B having a large opening area and are discharged out of the recording head first. By operating the suction pumps P1 and P3 communicating with the internal spaces H3102-A and H3102-B of the cap H3100 covering the discharge port groups H3002-A and H3002-B having a large opening area, a suction force is applied to the spaces. . At this time, the internal space H3101-A of the cap H3100 covering the discharge port group H3001-A having a small opening area is in a sealed state not communicating with the atmosphere. Accordingly, foreign matter in the ink supply path H1201 of the first plate H1200 or foreign matter in the ink flow path H1102 of the recording element substrate H1100 follows the ink flow in the direction of the black arrow and passes through the suction paths H3104 and H3105 to the recording head. It is discharged outside.

  After the suction recovery from the discharge port groups H3002-A and H3002-B having a large opening area is completed, the suction recovery of the discharge port group H3001-A having a small opening area is performed. At that time, since the discharge port groups H3002-A and H3002-B having a large opening area are sealed by the cap H3100, air to the discharge port groups H3002-A and H3002-B having a large opening area at the time of suction recovery is sealed. This prevents intrusion and prevents printing defects due to ink dropping.

  A second method for removing foreign substances clogged in the discharge port H3001 having a small opening area using the recording head H1001 having the configuration of this embodiment will be described below. As a second method of removing the foreign matter, the internal space H3101-A of the cap H3100 that covers the discharge port group H3001-A having a small opening area is brought into an air communication state. Further, the valve B provided on the upstream side of the ink flow path H1102 of the recording element substrate H1100 of the recording head H1001 is closed to prevent new ink from being supplied into the recording head H1001 from the ink supply unit side. In this state, the suction pumps P1 and P3 are operated to suck ink from the discharge port groups H3002-A and H3002-B having a large opening area. Since the discharge port H3001 of the discharge port group H3001-A having a small opening area is in communication with the atmosphere, foreign matter clogged in the discharge port H3001 having a small opening area, floating in the ink flow path H1102 of the recording element substrate H1100. The foreign matter to be discharged is discharged out of the recording head through the suction paths H3104 and H3105 together with the flow of both ink and air.

  After the suction recovery from the discharge port groups H3002-A and H3002-B having a large opening area is completed, the suction recovery of the discharge port group H3001-A having a small opening area is performed. At that time, the valve B is opened so that new ink is supplied into the recording head H1001 from the ink supply unit side. By operating the suction pump P2 in the above state, a suction force is applied in the internal space H3101 of the cap H3100, and the ink supply path H1102 of the recording element substrate H1100 is filled with new ink. If the inside of the ink flow path H1102 is not sufficiently filled with new ink by the second suction recovery method of the present embodiment, a suction force is applied to the internal space H3101 of the cap H3100, or the internal space of the cap H3100. The suction force may be applied to the internal spaces H3102-A and H3102-B of the cap H3100 at the same time as the suction force is applied to the H3101.

  In the present embodiment, the recording element substrate having only one ink supply path has been described. However, the same effect can be obtained even if the recording element substrate has a plurality of ink supply paths with respect to one recording element substrate. can get.

  In this example, the recording element substrate H1100 having the same configuration as that of Example 1 and suction recovery means such as a cap H3100 were used. In this embodiment, when suction is performed from the discharge port groups H3002-A and H3002-B having a large opening area, suction is alternately performed from one side of each of the discharge port group H3002-A and the discharge port group H3002-B. This is because, when suction is simultaneously performed from the discharge port groups H3002-A and H3002-B having a large opening area, a flow stagnation occurs in the vicinity of the region C shown in FIG. This is because the foreign matter in the path H1102 may not be sufficiently discharged.

  FIGS. 12 and 14 are side sectional views of the recording head H1100 when the cap H3100 covers the surface of the recording element substrate H1100 and the ink is discharged in a closed state. First, as shown in FIG. 12, by applying a suction force only to the internal space H3102-A of the cap H3100 that covers the ejection port group H3002-A having a large opening area, the inside of the ink supply path H1201 of the first plate H1200. Or foreign matter in the ink flow path H1102 of the recording element substrate H1100 is discharged out of the recording head through the suction path H3104 along the ink flow in the direction of the black arrow. Subsequently, as shown in FIG. 13, by applying a suction force only to the internal space H3102-B of the cap H3100 that covers the ejection port group H3002-B having a large opening area, the ink supply path H1201 of the first plate H1200. The foreign matter inside or the foreign matter inside the ink flow path H1102 of the recording element substrate H1100 is discharged out of the recording head through the suction path H3105 along the ink flow in the direction of the arrow.

  In this embodiment, ink is alternately sucked from one side of each of the ejection opening groups H3002-A and H3002-B having a large opening area, so that the ink flow path H1202 of the first plate H1200 and the ink flow of the recording element substrate H1100. The stagnation of the flow in the area near the path H1102 is eliminated, and the foreign matter in the ink flow path H1102 can be discharged out of the recording head. Furthermore, the ink may be alternately sucked a plurality of times from one side of each of the ejection port groups H3002-A and H3002-B having a large opening area as necessary.

  After the suction recovery from the discharge port groups H3002-A and H3002-B having a large opening area is completed, the suction recovery of the discharge port group H3001-A having a small opening area is performed. At that time, since the discharge port groups H3002-A and H3002-B having a large opening area are sealed by the cap H3100, air to the discharge port groups H3002-A and H3002-B having a large opening area at the time of suction recovery is sealed. This prevents intrusion and prevents printing defects due to ink dropping.

  Also in the present embodiment, as in the first embodiment, a second method for removing foreign substances clogged in the discharge port H3001 having a small opening area may be selected. That is, as a second method for removing foreign matter, the internal space H3101-A of the cap H3100 that covers the discharge port group H3001-A having a small opening area is brought into an air communication state. Further, the valve B provided on the upstream side of the ink flow path H1102 of the recording element substrate H1100 of the recording head H1001 is closed to prevent new ink from being supplied into the recording head H1001 from the ink supply unit side. In this state, the suction pumps P1 and P3 are alternately operated to suck ink alternately from the discharge port groups H3002-A and H3002-B having a large opening area. Since the discharge port H3001 of the discharge port group H3001-A having a small opening area is in communication with the atmosphere, foreign matter clogged in the discharge port H3001 having a small opening area, floating in the ink flow path H1102 of the recording element substrate H1100. The foreign matter to be discharged is discharged out of the recording head through the suction paths H3104 and H3105 together with the flow of both ink and air. After the suction recovery from the discharge port groups H3002-A and H3002-B having a large opening area is completed, the suction recovery of the discharge port group H3001-A having a small opening area is performed. At that time, the valve B is opened so that new ink is supplied into the recording head H1001 from the ink supply unit side. By operating the suction pump P2 in the above state, a suction force is applied in the internal space H3101 of the cap H3100, and the ink supply path H1102 of the recording element substrate H1100 is filled with new ink. If the inside of the ink flow path H1102 is not sufficiently filled with new ink by the second suction recovery method of the present embodiment, a suction force is applied to the internal space H3101 of the cap H3100, or the internal space of the cap H3100. The suction force may be applied to the internal spaces H3102-A and H3102-B of the cap H3100 at the same time as the suction force is applied to the H3101.

  In the present embodiment, the recording element substrate having only one ink supply path has been described. However, the same effect can be obtained even if the recording element substrate has a plurality of ink supply paths with respect to one recording element substrate. can get.

  FIG. 14 is a perspective view of the recording element substrate H1100 used in the third embodiment of the present invention. A discharge port group H3201-A in which a plurality of discharge ports H3201 having a small opening area are arranged on one side across the ink supply path H1102, and a discharge port group H3202 having a plurality of discharge ports H3202 having a large opening area arranged on the other side. -A is arranged. Ink is supplied from one ink supply path H1102 of the recording element substrate H1100 to both the discharge port group H3201-A having a small opening area and the discharge port group H3202-A having a large opening area. .

  FIG. 15 is a cross-sectional view of the recording element substrate H1100 indicated by arrows BB in FIG.

  In this embodiment, a cap H3300 shown in FIG. 16 is provided as a part of the suction recovery means of the recording head H1001 of the ink jet recording apparatus so as to correspond to the position of each discharge port group. The inside of the cap H3300 is partitioned into two spaces H3301 and H3302 so as to correspond to the discharge port group H3201-A having a small opening area and the discharge port group H3202-A having a large opening area, and the cap outer edge H3305 and the recording. Independent spaces are formed by contacting the surface of the element substrate H1100. Suction passages H3303 and H3304 connected to the suction pump are respectively provided in the caps covering the discharge port groups. Through these suction paths, a suction force can be applied independently to the spaces H3301 and H3302 partitioned inside the cap H3300. In this case, a suction pump may be provided for each suction path, or a valve is provided for each of the plurality of suction paths connected to the suction pump so that suction force is applied to each space partitioned inside the cap H3300. May be. Further, in this embodiment, the cap is formed integrally and has a shape as shown in FIG. 16 in which a partition is provided between each discharge port group. However, the cap is a separate cap arranged so as to be adjacent to each other. There may be.

  In this embodiment, when it is necessary to recover the suction of the recording head H1001, the recording head H1001 covers the surface of the recording element substrate H1100 outside the recording area where there is no recording medium, and the cap is closed. In this state, the suction pump is operated to apply a suction force to the partitioned spaces H3301 and H3302 inside the cap H3300. When performing the suction recovery operation, suction is performed from the discharge port group H3202-A having a large opening area prior to the recovery of the discharge port group H3201-A having a small opening area. This is because foreign matter floating in the ink supply path H1102 or foreign matter such as dust floating around the small ejection port group H3201-A and clogging the small ejection port H3201 during the recovery operation is opened. This is because the discharge port group H3202-A having a large area is recovered to discharge the recording head H1001 first.

  By operating a suction pump (not shown) communicating with the internal space H3302 of the cap H3300 that covers the discharge port group H3202-A having a large opening area, a suction force is applied to the space. At this time, the internal space H3301-A of the cap H3300 covering the discharge port group H3201 having a small opening area is in a sealed state not communicating with the atmosphere. Accordingly, the foreign matter in the ink supply path H1201 of the first plate H1200 or the foreign matter in the ink flow path H1102 of the printing element substrate H1100 is discharged out of the recording head through the suction path H3304 along the ink flow.

  After the suction recovery from the discharge port group H3202-A having a large opening area is completed, the suction recovery of the discharge port group H3201-A having a small opening area is performed. At that time, since the ejection opening group H3202-A having a large opening area is sealed by the cap H3300, the entry of air into the ejection opening group H3202-A having a large opening area at the time of suction recovery is prevented. Print defects can be prevented.

  Also in the present embodiment, as in the first embodiment, a second method for removing foreign substances clogged in the discharge port H3201 having a small opening area may be selected. That is, as a second method of removing foreign matter, the internal space H3301 of the cap H3300 that covers the discharge port group H3201-A having a small opening area is brought into an air communication state. Further, a valve (not shown) provided on the upstream side of the ink flow path H1102 of the recording element substrate H1100 of the recording head H1001 is closed to prevent new ink from being supplied into the recording head H1001 from the ink supply unit side. . In this state, a suction pump (not shown) is operated to suck ink from the discharge port group H3202-A having a large opening area. Since the discharge port H3201 of the discharge port group H3201-A having a small opening area is in communication with the atmosphere, foreign matter clogged in the discharge port H3201 having a small opening area, floating in the ink flow path H1102 of the recording element substrate H1100. The foreign matter to be discharged is discharged out of the recording head through the suction path H3304 together with the flow of both ink and air. After the suction recovery from the discharge port group H3202-A having a large opening area is completed, the suction recovery of the discharge port group H3201-A having a small opening area is performed. At that time, a valve (not shown) provided on the upstream side of the ink flow path H1102 of the recording element substrate H1100 of the recording head H1001 is opened, and new ink is supplied into the recording head H1001 from the ink supply unit side. Like that. In this state, a suction pump (not shown) communicating with the interior space H3301 of the cap H3300 is operated to apply a suction force to the space, thereby filling the ink supply path H1102 of the recording element substrate H1100 with new ink. When the inside of the ink flow path H1102 is not sufficiently filled with new ink by the second suction recovery method of the present embodiment, after applying a suction force to the internal space H3301 of the cap H3300, or the internal space of the cap H3300 A suction force may be applied to the internal space H3302 of the cap H3300 simultaneously with applying a suction force to the H3301.

  In the present embodiment, the recording element substrate having only one ink supply path has been described. However, the same effect can be obtained even if the recording element substrate has a plurality of ink supply paths with respect to one recording element substrate. can get.

  In the fourth embodiment of the present invention, the recording element substrate H1100 having the configuration shown in FIG. 14 and the cap H3400 having the shape shown in FIG. 17 are used. In this embodiment, as a part of the suction recovery means of the recording head H1001 of the ink jet recording apparatus, as shown in FIG. 17 so as to correspond to any of the ejection port groups H3201-A and H3202-B shown in FIG. An inner space H3401 is provided in the cap H3400. A suction path H3402 connected to a suction pump (not shown) is provided inside the cap, and suction force can be applied to the internal space H3401 of the cap H3400 through the suction path H3402.

  In this embodiment, when it is necessary to recover the suction of the recording head H1001, the cap H3400 covers the surface of the recording element substrate H1100 of the recording head H1001 outside the recording area where there is no recording medium, and the cap is closed. It becomes a state. In this state, a suction pump (not shown) is operated to apply a suction force to the internal space H3401 of the cap H3400. When performing the suction recovery operation, suction is performed from the discharge port group H3202-A having a large opening area prior to the recovery of the discharge port group H3201-A having a small opening area. This is because foreign matter floating in the ink supply path H1102 or foreign matter such as dust floating around the small ejection port group H3201 and clogging the small ejection port H3201 during the recovery operation is reduced in the opening area. This is because, by recovering from the large discharge port group H3202-A, the recording head H1001 is discharged first.

  FIG. 18A shows a state in which the cap is closed when ink is sucked from the ejection port group H3202-A having a large opening area. An internal space H3401 of the cap H3400 covers the discharge port group H3202-A having a large opening area, and an outer edge portion H3403 of the cap H3400 blocks the discharge port group H3201-A having a small opening area. In this state, by applying a suction force to the internal space H3401 of the cap H3400 that covers the discharge port group H3202-A having a large opening area, foreign matter in the ink supply path H1201 of the first plate H1200, or the printing element substrate The foreign matter in the ink flow path H1102 of H1100 is discharged out of the recording head H1001 through the suction path H3402 along the ink flow.

  After the suction recovery of the discharge port group H3202-A having a large opening area is completed, the suction recovery of the discharge port group H3201-A having a small opening area is performed. At this time, the cap closed state is once opened, and as shown in FIG. 18B, the inner space H3401 of the cap H3400 covers the discharge port group H3201-A having a small opening area, and the outer edge H3403 of the cap H3400 The position of the cap H3400 with respect to the recording element substrate H1100 is changed so as to close the ejection port group H3202-A having a large opening area. In any case, since the ejection port group that has not been suction-recovered is sealed by the outer edge H3403 of the cap H3400, air can be prevented from entering the ejection port group at the time of suction recovery, and printing defects due to ink loss can be prevented. Can be prevented.

  In the present embodiment, the recording element substrate having only one ink supply path has been described. However, the same effect can be obtained even if the recording element substrate has a plurality of ink supply paths with respect to one recording element substrate. can get.

FIG. 3 is a perspective view of a recording element substrate used in the recording heads of the first and second embodiments. FIG. 3 is an exploded perspective view illustrating a configuration of an ink jet recording head. FIG. 2 is a detailed exploded perspective view showing a configuration of an ink jet recording head. FIG. 2 is a perspective view showing an ink jet recording head. FIG. 6 is a perspective view showing a second recording element substrate used for an ink jet recording head. Sectional drawing of an inkjet recording head. FIG. 3 is a perspective view of an ink jet recording head. FIG. 3 is a perspective view of an ink jet recording head cartridge. FIG. 3 is a cross-sectional view of a recording element substrate used in the recording heads of the first and second embodiments. The perspective view of the cap used for a 1st, 2nd Example. FIG. 2A is a side sectional view showing a state where ink is discharged by the recording head of the first embodiment, and FIG. FIG. 6 is a side sectional view showing a state where ink is discharged by a recording head of a second embodiment. FIG. 6 is a side sectional view showing a state where ink is discharged by a recording head of a second embodiment. FIG. 9 is a perspective view of a recording element substrate used for recording heads of third and fourth embodiments. Sectional drawing of the recording element board | substrate used for the recording head of 3rd, 4th Example. The perspective view of the cap used for a 3rd Example. The perspective view of the cap used for the 4th example. A state where the discharge port group having a large opening area is cap-closed in the fourth embodiment (a), and a state where the discharge port group having a small opening area is cap-closed in the fourth embodiment (b). FIG. 2 is a perspective view showing an ink jet recording head.

Explanation of symbols

H1000 recording head cartridge H1001 recording head H1100 recording element substrate H1101 second recording element substrate H1102 ink supply path H1103 electrothermal conversion element H1104 electrode section H1105 bump H1106 ink flow path wall H1200 first plate H1300 electrical wiring tape H1500 ink supply unit H1800 ink tank H1801 tube

Claims (8)

In an inkjet recording apparatus comprising a recording element substrate having a plurality of ejection openings and having an ink supply path for supplying ink to the plurality of ejection openings.
The plurality of discharge ports are composed of a discharge port group having a large opening area and a discharge port group having a small opening area,
An ink jet recording apparatus comprising: a recovery unit that individually discharges ink from each of the discharge port group having a large opening area and the discharge port group having a small opening area. The discharge port group having a large opening area is disposed at an end in the arrangement direction of the discharge port group having a small opening area,
2. The ink jet recording apparatus according to claim 1, wherein the discharge ports of the discharge port group having a large opening area have a recording element substrate that is a dummy discharge port that does not contribute to recording. The inkjet recording apparatus according to claim 1, further comprising: a recording element substrate in which the ejection port group having the large opening area and the ejection port group having the small opening area are arranged to face each other.   The inkjet recording apparatus according to claim 1, further comprising a non-ejection detection unit for the recording element substrate.   The suction recovery method for an ink jet recording apparatus according to claim 1, wherein the discharge port group having a large opening area is recovered before the discharge port group having a small opening area.   6. The suction recovery method according to claim 5, wherein when the discharge port group having a large opening area is recovered, the discharge port group having a small opening area is opened to the atmosphere. A suction recovery method in an ink jet recording apparatus having a recording element substrate, wherein the discharge port groups having a large opening area are arranged at both ends in the arrangement direction of the discharge port groups having a small opening area, wherein the discharge ports having a large opening area The suction recovery method according to claim 5 or 6, wherein the recovery is performed alternately from the outlet group. In the ink jet recording apparatus having a recording element substrate in which the discharge port group having the large opening area and the discharge port group having the small opening area are arranged to face each other, when the recovery is performed from one discharge port group, the other 6. The suction recovery method according to claim 5, wherein the discharge port group is closed with an outer edge portion of the cap.

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