JP2006205663A - Liquid discharging head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid discharging head having such a constitution that foreign matters do not adhere on a section contacting with a pressing body of a filter and the rear surface thereof. <P>SOLUTION: In this liquid discharging head, the external edge section 103a of the filter 103, which is brought into contact with the pressing body 106 being provided on the liquid feeding port of an ink tank, is fixed to the opening section of a liquid introducing passage 102 by which the liquid being fed from the ink tank is introduced. On the surface of the filter 103 which is brought into contact with the pressing body 106, a flat section 103b which protrudes to the external edge section 103a is formed. The rear surface of the flat section 103b of the filter 103 is formed into a flat shape being flush with the external edge section 103a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid discharge head that performs recording by discharging a liquid.

  Conventionally, an ink jet recording apparatus (ink jet recording apparatus) that performs recording by discharging ink from a liquid discharge head onto a recording material is known. The ink jet recording apparatus can easily make the recording means compact, can record high-definition images at high speed, can record on plain paper without requiring special processing, and has low running cost. The non-impact method has advantages such as low noise and easy recording of a color image using multi-color inks. In particular, a line type recording apparatus using a line type liquid discharge head in which a large number of discharge ports are arranged in the sheet width direction can further increase the recording speed.

  As a liquid discharge head used in an ink jet recording apparatus, an ink tank for storing the supplied ink is formed separately from a liquid discharge head having a function of discharging ink, and the separate ink tank is liquid discharged. One that is detachable from the head is known. Further, in this manner, in which the liquid discharge head and the ink tank are detachable from each other, the ink tank is loaded with a porous member for holding the supplied ink, and the ink in such an ink tank An ink introducing portion on the liquid discharge head side fitted to the supply portion has been devised in which a filter is provided. By providing such a filter in the ink introduction part on the liquid discharge head side, an obstacle that prevents discharge of debris, dust, etc. of the porous member loaded in the ink tank side from the ink tank side enters the liquid discharge head. In addition, it is possible to prevent dust from entering from the outside with the ink tank removed.

  FIG. 5A is a cross-sectional view showing a liquid introducing portion of a conventional liquid discharge head disclosed in Patent Document 1. A liquid introduction path 202 is formed in the liquid introduction part 201 of the liquid discharge head, and a filter 203 is provided in the opening. The inner surface of the filter 203 is supported by a plurality of support columns 205 formed at the end of the liquid introduction unit 201, and the outer edge 203 a of the filter 203 is covered and fixed by a cover rib 204 attached to the end of the liquid introduction unit 201. Has been.

  The filter 203 is configured by pressing a disk-shaped filter member formed by stacking metal fibers in a non-woven shape and sintering it with a press device 207 as shown in FIG. 5B. Thus, the filter 203 has a flat portion 203b that is convex with respect to the outer edge portion 203a.

  When the ink tank is attached to the liquid ejection head, as shown in FIG. 5C, the flat portion 203b of the filter 203 of the liquid introduction unit 201 is brought into contact with the pressure contact body 206 provided in the ink supply unit of the ink tank. Accordingly, the flat portion 203b of the filter 203 comes into contact with the surface of the substantially flat pressure contact body 206, and the filter 203 can be brought into contact with the pressure contact body 206 in a homogeneous contact state.

Compared to the normal recording operation, a large amount of ink is supplied from the ink tank to the liquid discharge head when the liquid discharge head is sucked and recovered, such as when sucking out thickened ink near the discharge port of the liquid discharge head. Ink flows from the pressure contact body 206 to the filter 203 at a high speed. Even in such a case, in the configuration in which the filter 203 and the press contact body 206 are in proper contact as described above, the possibility that air is sucked from the contact portion is low. The possibility of recording failure due to interruption of ink supply due to air bubbles is reduced.
JP 2002-137410 A

  However, the liquid introduction part of the conventional liquid discharge head shown in FIGS. 5A to 5C has the following problems.

  The filter 203 is deformed by the press device 207 and is formed in a shape having a convex flat portion 203b at the center. Therefore, the filter 203 has a concave shape on the back surface of the flat portion 203b. In order to form the filter 203 in such a shape, the press device 207 presses the surface of the filter 203 that contacts the pressure contact body 206 and the back surface thereof. The filter 203 formed by such processing is in contact with the press device 207 in contact with the press contact body 206 and the back surface thereof. Dust or the like may adhere to the filter 203. It is also conceivable that the metal fibers of the filter 203 are broken and missing due to the compressive force or shearing force applied to the filter 203 during the press working.

  If foreign matter such as dust or metal fiber pieces adheres to the filter 203, when the ink tank is connected and ink is supplied, the foreign matter flows into the liquid introduction path 202 together with the ink flow. Eventually, it may reach the discharge port of the liquid discharge head and clog the discharge port, resulting in a recording failure such as non-discharge of ink.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid discharge head having a configuration in which foreign matter does not adhere to a portion of a filter that comes into contact with a pressure contact body and the back surface thereof.

  In order to achieve the above object, the liquid discharge head of the present invention abuts a pressure contact member provided at a liquid supply port of the ink tank at an opening of a liquid introduction path into which liquid supplied from the ink tank is introduced. In the liquid discharge head in which the outer edge portion of the filter to be fixed is fixed, a convex flat portion with respect to the outer edge portion is formed on the surface of the filter that is in contact with the pressure contact body. The back surface of the flat portion is formed in a flat shape that is flush with the outer edge portion.

  According to the present invention, it is possible to provide a liquid discharge head having a configuration in which foreign matter does not adhere to the portion of the filter that contacts the pressure contact body and the back surface thereof.

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1A is a cross-sectional view showing a liquid introduction part of a liquid ejection head according to an embodiment of the present invention.

  The liquid introduction part 101 of the liquid ejection head in the present embodiment is also provided with a liquid introduction path 102 in the same manner as the conventional one shown in FIG. 5A and the like, and a filter 103 is provided at the opening. The inner surface of the filter 103 is supported by a plurality of columns 105 formed at the end of the liquid introduction path 102, and the outer edge portion 103 a of the filter 103 is covered and fixed by a cover rib 104 attached to the end of the liquid introduction portion 101. Has been. When the liquid introduction part 101 and the cover rib 104 are made of, for example, a thermoplastic resin, the filter 103 is positioned at the end part (liquid introduction port) of the liquid introduction path 102 and the back side of the outer edge part 103a of the filter 103 Is fixed to the end portion of the liquid introducing portion 101 by heat welding, and then the covering rib 104 is attached to the end of the outer edge portion 103a and the liquid introducing portion 101 so that the covering rib 104 covers the surface side of the outer edge portion 103a of the filter 103. The filter 103 can be attached to the liquid introduction part 101 by fixing to the part by thermal welding.

  The filter 103 of the present embodiment is also configured by pressing a disk-shaped filter member formed by stacking metal fibers in a nonwoven fabric shape and sintering the same with a press device 107 as shown in FIG. 1B. Is done. The press device 107 presses only the portion that becomes the outer edge portion 103a of the filter member, and does not contact the portion that becomes the flat portion 103b of the filter member and the back surface thereof. Therefore, even if dust or the like adheres to the press device 107, the dust or the like does not adhere to the flat portion 103b of the filter 103 and the back surface thereof. A filter having a convex flat portion 103b with respect to the outer edge portion 103a and having no flat surface 103b and its back surface free of dust and the like by pressing a disk-shaped filter member with such a press device 107. 103 is formed.

  When the ink tank is mounted on the liquid ejection head, as shown in FIG. 1C, the flat portion 103b of the filter 103 is brought into contact with the pressure contact body 106 provided in the ink supply portion of the ink tank. Thereby, the flat portion 103b of the filter 103 comes into contact with the surface of the substantially flat pressure contact body 106, and the filter 103 can be brought into contact with the pressure contact body 106 in a homogeneous contact state. In addition, the press-contacting body 106 is comprised by compressing a fiber, for example.

  Here, the step between the outer edge portion 103a and the flat portion 103b of the filter 103 is preferably about 50 to about 100 μm. If this level difference is large, the metal fibers in the level difference part tend to break when pressing is performed and metal fiber pieces tend to be generated. On the other hand, since the height of the cover rib 104 is usually about 30 μm from the outer edge portion 103 a of the filter 103, the cover rib 104 becomes higher than the flat portion 103 b of the filter 103 when this step is small. Sometimes. If the cover rib 104 is higher than the flat portion 103 b of the filter 103, the cover rib 104 comes into contact with the pressure contact body 106 when the ink tank is connected to the liquid discharge head, and the filter 103 cannot make good contact with the pressure contact body 106. . Therefore, by setting the step to about 50 to 100 μm, it is possible to suppress the metal fiber from being broken and the metal fiber piece from dropping off during the press working, and to make the filter 103 contact the pressure contact body 106 satisfactorily. .

  As described above, the filter 103 according to the present embodiment has a flat portion 103 b that is convex with respect to the outer edge portion 103 a on the surface that is in contact with the pressure contact body 106 of the ink tank, and the back surface of the flat portion 103 b of the filter 103. Can be formed by pressing only the outer edge portion 103a by the press device 107, since it has a structure formed in the same shape as the outer edge portion 103a. Therefore, it is possible to prevent dust and the like from adhering to the flat portion 103b of the filter 103 and the back surface of the filter 103 during press working by the press device 107. In addition, since the flat portion 103b of the filter 103 and the back surface thereof are not subjected to press work, a metal fiber piece by press work is hardly generated in the portion. Therefore, when an ink tank is connected to the liquid discharge head and ink is supplied, foreign matters such as dust and metal fiber pieces flow into the liquid introduction path 102 together with the ink flow, and eventually reach the discharge port of the liquid discharge head. As a result, it is possible to prevent the ejection port from being clogged and causing a recording failure such as non-ejection of ink.

  2 to 4 are diagrams for explaining the configurations and relationships of the preferred head cartridge, liquid ejection head, and ink tank 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 FIG. 2 and FIG. 3, the recording head (liquid ejection head) H1001 of this embodiment is one constituent element of the recording head cartridge H1000. The recording head cartridge H1000 includes the recording head H1001 and the recording head. The ink tank H1900 (H1901 to H1904) is detachably provided on the H1001.

  The recording head H1001 is a bubble jet (registered trademark) side that performs recording using an electrothermal transducer (recording element) that generates thermal energy for causing film boiling of ink in response to an electrical signal. A shooter-type recording head, which ejects ink (recording liquid) supplied from an ink tank H1900 from an ejection port in accordance with recording information. This recording head cartridge H1000 is detachably fixed and supported by positioning means and electrical contacts of a carriage (not shown) provided in the ink jet recording apparatus main body.

  Ink tank H1901 is an ink tank for black ink, ink tank H1902 is for cyan ink, ink tank H1903 is for magenta ink, and ink tank H1904 is an ink tank for yellow ink. Each of the ink tanks H1901, H1902, H1903, and H1904 is detachable with respect to the ink supply member H1500 provided in the recording head H1001, and the ink tanks can be replaced in this manner, so that the ink jet recording can be performed. The ink tanks for the respective colors can be individually replaced in accordance with the consumption amount that differs for each color depending on the apparatus.

  As shown in FIG. 4, each ink tank H1900 is formed with an ink supply port H1907 for supplying ink in the ink tank H1900 to the recording head H1001. For example, when an ink tank H901H containing black ink is attached to the ink supply member H1500 of the recording head H1001, the ink supply port H1907 of the ink tank H1901 is pressed against the filter H1700 provided at the joint H1520 of the ink supply member H1500. Then, the black ink in the ink tank H1901 passes through the first plate H1200 provided in the recording head H1001 from the ink supply port H1907 via the ink flow path H1501 of the ink supply member H1500, and is also provided in the recording head H1001. It is supplied to the first recording element substrate H1100. The ink supplied to the bubbling chamber in which the electrothermal conversion element (not shown) and the ejection port (not shown) are formed in the first recording element substrate H1100 is given to the electrothermal conversion element. It is discharged from the discharge port by the generated thermal energy.

  Referring to FIG. 4, 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. The ink supply member H1500 that detachably holds the ink tank H1900 is a component part of the ink supply unit that guides ink from the ink tank H1900 to the recording element unit H1002. The flow path forming member H1600 is ultrasonically welded, and the ink is supplied. An ink flow path H1501 extending from the tank H1900 to the first plate H1200 is formed.

  A filter H1700 that prevents entry of dust from the outside is joined to the joint portion H1520 engaged with the ink tank H1900 by welding, and a seal rubber H1800 is attached to prevent evaporation of ink from the joint portion H1520. Has been. The ink supply member H1500 also has a function of holding a detachable ink tank H1900, and has a hole H1503 in which a claw H1910 of the ink tank H1900 is engaged.

FIG. 4 is a cross-sectional view showing a liquid introduction part of a liquid ejection head according to an embodiment of the present invention. It is a figure which shows a mode that the filter of the recording head shown to FIG. 1A is formed with a press apparatus. FIG. 1B is a diagram illustrating a state in which a filter of the recording head illustrated in FIG. 1A is in contact with a pressure contact body of an ink tank. FIG. 2 is a perspective view showing a head cartridge to which the liquid discharge head (recording head) shown in FIG. 1 is applied. FIG. 3 is a perspective view showing the head cartridge shown in FIG. 2 in a state where a recording head and an ink tank are separated. FIG. 3 is a cross-sectional view illustrating a configuration of an ink supply member provided in the recording head illustrated in FIG. 2. It is sectional drawing which shows the liquid introduction part of the conventional liquid discharge head. It is a figure which shows a mode that the filter of the liquid discharge head shown to FIG. 5A is formed with a press apparatus. It is a figure which shows the state which made the filter of the liquid discharge head shown to FIG. 5A contact | abut to the press-contacting body of an ink tank.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Liquid introduction part 102 Liquid introduction path 103 Filter 103a Outer edge part 103b Flat part 104 Cover rib 105 Strut 106 Pressure contact body 107 Press apparatus

Claims (3)

A liquid discharge head in which an outer edge portion of a filter that is in contact with a pressure contact body provided at a liquid supply port of the ink tank is fixed to an opening portion of a liquid introduction path into which liquid supplied from an ink tank is introduced ,
The surface of the filter that is in contact with the pressure contact body is formed with a flat portion that is convex with respect to the outer edge portion, and the back surface of the flat portion of the filter is a flat surface that is flush with the outer edge portion. A liquid discharge head having a shape.   The liquid ejection head according to claim 1, wherein the filter is formed by pressing only the outer edge portion.   The liquid discharge head according to claim 1, wherein the filter is configured by sintering metal fibers.

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