JP2006315419A - Ink cartridge and method for charging ink - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink cartridge which can certainly prevent air and impurities from invading into an ink holder while making the operation of charging the ink easier. <P>SOLUTION: The cartridge is equipped with a cartridge housing 4b with the ink holder. The cartridge housing 4b is provided with the first opening 7a and the second opening 7b which are opened to the outside, and the openings communicate with the ink holder through communication passages 5a and 5b, respectively. The first bung member 6a and the second bung member 6b are fitted to two openings of 7a and 7b, respectively. The bung members 6a and 6b can be passed by hollow needles, and the members have an elasticity enabling sealing by itself after pulling out the needles. A part of the second bung member 6b is provided with a protrusion 6z which is a valve part capable of sealing the communication passage 5b. The bung member 6b is fitted to the second opening 7b so that the member 6b may be moved to the positions for opening and sealing the communication passage, respectively by the protrusion 6z. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique of an ink cartridge that is used by being set in an apparatus.

  2. Description of the Related Art Conventionally, an ink cartridge for supplying ink to an apparatus that uses ink by supplying the ink to the apparatus is known. An example of an apparatus that uses ink is an ink jet recording apparatus. This ink jet recording apparatus includes an ink jet head having nozzles, and is configured to form a desired image by ejecting fine droplets of ink from the nozzles. In this configuration, the ink cartridge has an ink reservoir, and the ink in the ink reservoir is supplied to the inkjet head of the apparatus.

  The configuration using the ink cartridge has an advantage that ink can be replenished by a simple operation of replacing the ink cartridge with a newly purchased ink when it runs out, and is widely spread.

  In one of the general configurations of the ink cartridge, an ink reservoir for containing ink is formed in a cartridge housing, and an opening formed outside the housing and the ink reservoir are connected via a communication path. After connecting, there is a configuration in which a plug member such as a rubber plug is fitted into the opening and sealed.

  In this configuration, the ink cartridge mounting portion formed on the apparatus main body side is provided with a hollow needle protruding at a position corresponding to the opening. When the ink cartridge is attached to the attachment portion, the hollow needle penetrates the plug member so that ink can be sucked from the ink reservoir through the communication path / hollow needle. is doing.

  In light of the example of the ink jet recording apparatus described above, the hollow needle is connected to the ink jet head for printing via a pipe or the like. Thus, ink can be supplied from the ink cartridge to the ink jet head.

  Here, if air or impurities enter the ink reservoir of the ink cartridge from the outside, bubbles and impurities inside the ink are supplied to the apparatus together with the ink, causing trouble. For example, in the case of the above-described ink jet recording apparatus, if there is a bubble, it causes dot dropout during printing, and if there is an impurity, it causes the nozzle of the ink jet head to become clogged.

  Therefore, a configuration that can reliably prevent such intrusion of air and impurities has been desired.

  On the other hand, at the stage of manufacturing the ink cartridge, there is a demand for a structure that can easily fill and fill the ink reservoir with ink and can reduce the number of manufacturing steps.

  That is, there has been a demand for a configuration that can smoothly fill the ink from the outside during the manufacture of the cartridge, and that can reliably prevent the entry of air and impurities from the outside once the ink has been filled.

The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described.

That is, according to the first aspect of the present invention, an ink reservoir forming body having an ink reservoir for containing ink, an opening that opens to the outside at an end surface of the ink reservoir forming body, and is formed at a predetermined depth from the end surface; A communicating passage having a diameter smaller than that of the opening communicating with the opening at a position away from the end surface of the opening and communicating with the opening and the ink reservoir; And an elastic member having elasticity that can be sealed by itself after removing the hollow needle, and a part of the elastic member, and the elastic member is fitted in the opening. And a valve portion that is movable to a position for sealing the communication path and a position for opening the communication path based on the movement of the elastic member .

According to a second aspect of the present invention, the elastic member has a length in the depth direction of the opening that is fully pushed into the opening when the valve portion is in a position to seal the communication path. It is.

According to a third aspect of the present invention, the communication passage communicates with the inner bottom surface of the opening, and the valve portion closes the communication passage in a state where the plug member is pushed into the inner bottom surface of the opening. It is.

According to a fourth aspect of the present invention, the communication passage communicates with a side surface of the opening, and the valve portion is constituted by a side surface portion of the plug member .

According to a fifth aspect of the present invention, the communication passage communicates with the inner bottom surface of the opening at a position eccentric with respect to the central axis of the opening, and the valve member is pushed by the plug member into the inner bottom surface of the opening. In this state, the communication path is closed.
The ink filling method according to claim 6 , wherein the ink reservoir forming body having an ink reservoir for containing ink and the outside of the ink reservoir forming body are opened to the outside and formed at a predetermined depth from the end surface. An opening, a communication path having a smaller diameter than the opening communicating with the opening at a position away from the end surface of the opening, and communicating with the opening and the ink reservoir, and movably fitted to the opening; An elastic member having elasticity that can penetrate the hollow needle and that can be sealed by itself after the hollow needle is pulled out, and a valve portion that is provided in a part of the elastic member and that can seal the communication path An ink filling method for an ink cartridge comprising: the elastic member penetrating the hollow needle through the elastic member in a state where the elastic member is fitted to the opening at a position where the valve portion opens the communication path. Through the hollow needle After the ink has been filled into the reservoir serial ink, the elastic member, wherein the valve portion is to move to a position for sealing the communication passage.

  Since this invention was comprised as mentioned above, there exist the following effects.

That is, as shown in claim 1, an ink reservoir forming body having an ink reservoir for containing ink, and an end surface of the ink reservoir forming body is opened to the outside, and is formed at a predetermined depth from the end surface. An opening, a communication path having a smaller diameter than the opening communicating with the opening at a position away from the end surface of the opening, and communicating with the opening and the ink reservoir, and movably fitted to the opening; An elastic member that can penetrate the hollow needle and has elasticity that can be sealed by itself after the hollow needle is pulled out, and is provided in a part of the elastic member, and the elastic member is fitted into the opening. The elastic member includes a valve portion that can be moved to a position for sealing and opening the communication path based on the movement of the elastic member in a state, so that the elastic member includes a fitting portion for the opening and a valve portion. , Will perform a double sealing action. Accordingly, it is possible to avoid a problem that ink leaks from the ink reservoir to the outside through the opening / communication passage, or air or impurities enter the ink reservoir through the opening / communication passage to cause an ink quality trouble.

In addition , when filling ink during cartridge manufacture, the valve portion can be opened for smooth ink filling. On the other hand, when the cartridge is used, the valve portion is sealed to allow air or impurities to enter the ink reservoir. Can be prevented.

According to a sixth aspect of the present invention, there is provided an ink filling method including an ink reservoir having an ink reservoir for containing ink, and an external opening at an end face of the ink reservoir forming body, and having a predetermined depth from the end face. An opening, a communication path having a smaller diameter than the opening communicating with the opening at a position away from the end surface of the opening, and communicating with the opening and the ink reservoir, and movably fitted to the opening; An elastic member having elasticity that can penetrate the hollow needle and that can be sealed by itself after the hollow needle is pulled out, and a valve portion that is provided in a part of the elastic member and that can seal the communication path An ink filling method for an ink cartridge comprising: the elastic member penetrating the hollow needle through the elastic member in a state where the elastic member is fitted to the opening at a position where the valve portion opens the communication path. Through the hollow needle After filling the ink reservoir tank, the elastic member, since the valve portion is moved to a position to seal the communication passage when the ink filling during cartridge manufacture opens the valve portion smoothly ink filling On the other hand, when the cartridge is used, the valve portion can be sealed to prevent air and impurities from entering the ink reservoir. In addition, the opening and closing of the valve portion can be performed by a simple operation only by moving the elastic member.

  First, a multifunction machine as an ink jet recording apparatus will be described with reference to FIG.

  FIG. 1 is a side view showing an overall configuration of a multifunction machine to which the present invention is applied.

[Overall configuration of the device]
The ink jet recording apparatus shown in FIG. 1 is a so-called multifunction machine type recording apparatus in which an ink jet recording type printer is provided with a scanner function and a fax function.

  That is, the multi-function device 30 includes a flat bed type scanner unit 20 and an ink jet printer unit 10 located immediately below the scanner unit 20 in a single housing.

  The scanner unit 20 includes a flat bed reading unit 21 having a substantially rectangular parallelepiped shape on the upper surface side of the multifunction machine 30. In the reading unit 21, image data can be scanned by scanning a document placed on the document glass 22 with the contact image sensor 25.

  The inkjet printer unit 10 is configured such that a paper feed tray 11 is provided obliquely on the back side (left side in FIG. 1) of the multifunction machine 30. The paper (image recording medium) set on the paper feed tray 11 is fed one by one by driving a pickup roller 12 provided on the paper feed tray 11 and provided below the scanner unit 20. It is conveyed to the print engine 13.

  Although details of the print engine 13 are not shown in the drawings, the print engine 13 includes a platen roller that conveys the paper while contacting it, an inkjet head that will be described later for ejecting fine droplets of four colors of ink onto the conveyed paper, and the like. Has been.

  The paper is transported along a transport path formed in the print engine 13 and a desired color is formed by ejecting fine droplets of ink from the ink jet head onto one surface of the paper. An image is formed. A sheet discharge tray 15 is provided on the front side (right side in FIG. 1) of the multifunction machine 30, and the sheet after image formation is discharged onto the sheet discharge tray 15.

  The ink cartridge mounting unit 14 of the inkjet printer unit 10 is configured on the front side of the multifunction machine 30 and at a position below the paper discharge tray 15.

  A horizontal and plate-like first cover 14a is installed so as to cover the upper side of the cartridge mounting portion 14, and a second cover 14b covering the front side of the cartridge mounting portion 14 is hinged to the first cover 14a. 16 is pivotally supported. Accordingly, the ink cartridge 1 can be set in the ink cartridge mounting portion 14 inside the covers 14a and 14b by rotating and opening the second cover 14b upward. FIG. 1 shows a state where the ink cartridge 1 has already been mounted.

  The ink cartridge mounting portion 14 is configured so that four color (yellow, magenta, cyan, black) ink cartridges 1 can be mounted side by side (however, for convenience of explanation, only one is shown in the drawing).

  In the ink cartridge mounting portion 14, the hollow needle 8 protrudes toward the front side of the apparatus. By setting the ink cartridge 1 in the mounting portion 14, the ink reservoir in the ink cartridge 1 is passed through the hollow needle 8. Ink is sucked and can be supplied to the inkjet head. Details of this configuration will be described later.

  Next, an outline of a connection configuration between the ink cartridge mounting portion 14 and the inkjet head will be described with reference to FIG.

  FIG. 2 is a schematic view showing a connection configuration between the ink cartridge and the recording head and a purge mechanism.

  As shown in FIG. 2, the hollow needle 8 provided in the mounting portion 14 is connected to a recording head unit 42 via a tube 41 provided in the multifunction machine 30. An ink reservoir 2 is formed inside the ink cartridge 1, and the ink sucked from the ink reservoir 2 through the hollow needle 8 is provided in the upper portion of the recording head unit 42 via the tube 41. Sent to the air trap 43. The air trap 43 is for trapping air bubbles generated in the tube 41 so as not to reach the downstream inkjet head 45 by retaining the air bubbles upward due to the buoyancy. In addition, the lump of the bubble which stayed is shown with the code | symbol 44. FIG.

  The recording head unit 42 has the inkjet head 45, and a plurality of nozzles 46 for ink ejection are opened in the inkjet head 45. A plurality of pressure chambers 47 are formed inside the ink jet head 45 and communicated with the nozzles 46, and the volume of the pressure chamber 47 is changed by an actuator 56 made of a piezoelectric element to impart ejection energy to the ink. The nozzle 46 is configured to inject. A common ink chamber 48 communicates with the pressure chamber 47, and ink from the air trap 43 can be supplied to the common ink chamber 48 through an ink supply port 49. Reference numeral 55 denotes a filter for filtering impurities in the ink.

  A purge mechanism 60 provided close to the inkjet head 45 includes a purge cap 61 for covering the nozzle 46 of the inkjet head 45, a purge pump 63 for sucking ink, and an intake port of the purge cap 61 and the purge pump 63. And a waste liquid absorbing member 64 installed on the discharge port side of the purge pump 63. As shown in FIG. 1, the waste liquid absorbing member 64 is disposed in the multifunction machine 30 at a position directly below the print engine 13.

  With this configuration, the purge cap 61 is at a position spaced apart from the inkjet head 45 during printing, but the purge cap 61 covers the nozzles 46 of the inkjet head 45 as shown in FIG. In this manner, the ink jet head 45 is in close contact with the ink jet head 45. When the purge pump 63 connected to the purge cap 61 is driven in this state, a strong suction flow is generated in the pressure chamber 47, the common ink chamber 48, the air trap 43, and the tube 41, and bubbles mixed in the ink. And impurities are sucked out of the nozzle 46 together with the ink. The sucked out bubbles and the ink mixed with impurities are discarded by being soaked into the waste liquid absorbing member 64 from the tube 62.

  As a result, the flow path inside the inkjet head 45 and the bubbles and impurities in the tube 41 can be removed, and the print quality can be prevented from deteriorating.

[Configuration of ink cartridge]
Next, a specific configuration of the ink cartridge mounted on the cartridge mounting unit 14 will be described.

  FIG. 3 is a partial cross-sectional view of a plan view showing a specific configuration of the ink cartridge. 4A is a partial cross-sectional perspective view of the rubber plug, and FIG. 4B is a perspective view showing the configuration of the peripheral portion of two openings of the cartridge housing.

  FIG. 5 is an enlarged view of a circled portion of FIG. 3 showing details of the check valve installed in the opening.

  As shown in FIG. 3, the ink cartridge 1 includes a cartridge housing 4 having a configuration in which a lower half 4b and an upper half 4t are integrally joined. The cartridge housing 4 is formed of a synthetic resin (polypropylene in the present embodiment), and includes an ink reservoir 2 that can store ink, two openings 7 a and 7 b provided on the outer surface of the housing 4, and openings 7 a. 7 b and communication passages 5 a and 5 b that connect the ink reservoir 2.

[Ink reservoir]
First, the configuration of the ink reservoir 2 will be described.

  As shown in FIG. 2, a recessed curved housing recess 2 a is formed on the upper surface of the lower half 4 b of the cartridge housing 4. Moreover, the flexible film 2b is installed so that the upper surface of the whole accommodation recessed part 2a may be covered. The peripheral edges of the film 2b and the housing recess 2a are bonded to each other by ultrasonic waves or heat, and the ink reservoir 2 is formed by the film 2b and the housing recess 2a.

[Opening]
Next, the configuration of the openings 7a and 7b will be described.

  As shown in FIG. 3 or FIG. 4B, the lower half 4b of the cartridge housing 4 is formed with two columnar openings, that is, a first opening 7a and a second opening 7b. The two openings 7a and 7b are formed side by side on the end face on one side in the longitudinal direction of the cartridge housing while being close to each other.

  The first opening 7a is for sucking ink from the ink reservoir 2 and supplying it to the inkjet head 45, and the second opening 7b is for injecting ink into the ink reservoir 2 when the ink cartridge 1 is manufactured. It is. The first opening 7a is formed slightly larger than the second opening 7b.

[Communication passage]
Next, the configuration of the communication paths 5a and 5b will be described with reference to FIG. 3 and FIG. 4 (b).

  That is, the lower half 4b of the cartridge housing 4 is provided with a first series passage 5a and a second communication passage 5b for connecting the openings 7a and 7b to the ink reservoir 2, respectively.

  One end of the first series passage 5a communicates with the center position of the inner bottom surface of the opening 7a formed in a circular shape while forming a taper shape spreading toward the end. On the other hand, one end of the second communication path 5b is communicated with a position (eccentric position) slightly deviated from the central axis of the opening on the inner bottom surface of the circular opening 7b.

  The other communication passages 5a and 5b have the other end opened to the ink reservoir 2 (specifically, the portion near the bottom of the housing recess 2a).

〔Rubber stopper〕
Next, the structure of the rubber plug 6 fitted into the openings 7a and 7b will be described.

  The rubber plug 6 is made of an elastic member such as silicon rubber. As shown in FIG. 4A, the first plug member 6a corresponding to the first opening 7a and the second plug corresponding to the second opening 7b. The member 6b is configured as an integrated body having a shape in which the members 6b are connected to each other via a thin plate-like connection portion 6c. By doing so, the first plug member 6a and the second plug member 6b, which are small and fine parts, can be handled in an integrated manner, and the parts can be easily handled during manufacturing.

  A groove 19 having an appropriate depth is formed on one end surface of the cartridge housing 4 where the openings 7a and 7b are formed so as to connect the two openings 7a and 7b. 6c is formed so that one surface thereof is flush with one end surface (surface opposite to the opening insertion direction) of the first plug member 6a and the second plug member 6b.

  Accordingly, when the two plug members 6a and 6b of the rubber plug 6 are completely fitted into the openings 7a and 7b, the connection portion 6c is accommodated in the groove 19 portion accordingly, so that the openings 7a and 7b In this configuration, unnecessary convex portions are not formed on the surface of the formed cartridge housing 4. Accordingly, the appearance of the ink cartridge 1 can be made clear, and a protective film 18 described later can be easily attached.

  Each of the first plug member 6a and the second plug member 6b has a cylindrical portion 6x that is cylindrical, and a blocking wall 6y that closes the inside of the cylindrical portion 6x in the axial direction. The thickness t of the blocking wall 6y is thinner than the axial length h of the cylindrical portion 6x (t <h). As a result, the hollow needle 8, the air suction needle 51 and the ink filling needle 52, which will be described later, can be easily passed through the plug members 6a and 6b. Details of this effect will be described later.

  The outer diameter of the cylindrical portion 6x is formed larger than the inner diameter of the corresponding openings 7a and 7b. Therefore, when the rubber plug 6 is fitted into the openings 7a and 7b, the cylindrical portion 6x is fitted while being appropriately compressed in the radial direction, so that the outer peripheral surface of the cylindrical portion 6x and the openings 7a and 7b Adhesion with the peripheral surface is ensured, and the ink is prevented from leaking to the outside by the sealing effect. In addition, with the above-described configuration, a large resistance is generated when attempting to remove the fitted rubber plug 6, so that even if a force that pulls out the rubber plug 6 is applied, the rubber plug 6 can be easily removed. There is no such thing.

  Furthermore, the connecting portion 6c that connects the two plug members 6a and 6b is connected to the plug members 6a and 6b on the outside of the cartridge housing 4 and is thinner than the plug members 6a and 6b. It is formed so that.

  With this configuration, when the two plug members 6a and 6b are completely fitted into the openings 7a and 7b, for example, the hollow needle 8 is caught on the connection portion 6c, or the user accidentally protects the later-described protection. Even when the film 18 is peeled off and the connection portion 6c is pulled and pulled from the outside, the plug members 6a and 6b do not come out of the openings 7a and 7b. This is because, when such a strong force is applied, the thin connection portion 6c is cut before the plug members 6a and 6b are pulled out of the openings 7a and 7b.

  Accordingly, the plug members 6a and 6b can be prevented from being removed from the openings 7a and 7b, and leakage of ink from the ink reservoir 2 to the outside can be reliably prevented.

  The outer peripheral surface of the cylindrical part 6x is slightly tapered on one side in the axial direction (side facing the openings 7a and 7b), and the work of fitting the cylindrical part 6x into the openings 7a and 7b is performed. Care is taken to make it easier.

  In the cylindrical part 6x of the first plug member 6a, the inner peripheral surface and the outer peripheral surface have the same axis. On the other hand, in the cylindrical portion 6x of the second plug member 6b, since the inner peripheral surface is provided at a position eccentric with respect to the outer peripheral surface, a thick portion and a thin portion in the radial direction are formed. Yes.

  A conical projection 6z is formed on the lower surface of the thick portion of the cylindrical portion 6x of the second plug member 6b so as to protrude from the second plug member 6b. The projection 6z is formed as a part of the second plug member 6b at a position corresponding to the second communication path 5b. When the rubber plug 6 is fitted into the openings 7a and 7b, the second communication path is formed. 5b is brought into close contact with the portion connected to the bottom of the second opening 7b so that the connecting portion can be sealed.

〔Check valve〕
Next, the check valve 3 disposed at the bottom of the first opening 7a will be described. The check valve 3 is provided to prevent air bubbles and impurities from entering the ink reservoir 2, and from the ink reservoir 2 side to the first opening 7a (first plug member 6a) side. The ink flow is allowed, but the ink flow from the first opening 7a (first stopper member 6a) toward the ink reservoir 2 is blocked.

  As shown in FIG. 5 which is an enlarged view, the check valve 3 is an assembly (check valve assembly 3x) in which three members of a valve support member 3a, a valve body 3b, and a cover 3c are integrally assembled. It is provided at a position straddling the first series passage 5a from the bottom of the opening 7a.

  Hereinafter, each of the three parts constituting the check valve assembly 3x will be described.

  The valve support member 3a is formed of a synthetic resin, and has a circular bottom plate 3a1 and a cylindrical side wall 3a2 that rises vertically at the periphery of the bottom plate 3a1, and has a cross-sectional “U” shape like a pan shape. Is done. A valve seat 3a3 is formed in a flat surface on the upper surface of the bottom plate 3a1 (inner bottom surface of the valve support member 3a), and a support hole 3a4 is formed at the center thereof, and around the support hole 3a4. A plurality of flow holes 3a5 are formed.

  The valve body 3b is a main part of the check valve 3, and is made of silicon rubber. The valve body 3b is formed in a substantially mushroom shape having an umbrella portion 3b1 and a stem portion 3b2, and the stem portion 3b2 is inserted into the support hole 3a4, so that the valve body 3b extends in the axial direction of the support hole 3a4. Displaceable. As a result, the valve body 3b is in close contact with the valve seat 3a3 of the valve support member 3a and closes the flow hole 3a5 (closed) by the movement in the axial direction and the elastic deformation of the umbrella portion 3b1. State) and a state in which the umbrella portion 3b1 is separated from the valve seat 3a3 and opens the flow hole 3a5 (open state).

  The cover 3c is fixed by being fitted to the side wall 3a2 of the valve support member 3a so as to cover one side (the side opposite to the valve seat 3a3) of the umbrella part 3b1 of the valve body 3b. A communication hole 3c1 is formed in the cover 3c so that ink that has flowed from the ink reservoir 2 side through the first series passage 5a can flow toward the outside of the housing 4. In addition, in order to ensure the stroke of displacement of the valve body 3b, an appropriate space is secured between the inner surface of the cover 3c and the valve seat 3a3.

  Furthermore, a receiving surface 3c2 is formed at the center of the outer surface of the cover 3c so as to contact a filter 17 described later. A ring groove 3c3 is formed around the receiving surface 3c2 so as to face the filter 17, and the ring groove 3c3 is connected to the communication hole 3c1.

[Ink cartridge manufacturing process]
Next, the manufacturing process of the ink cartridge 1 will be described focusing on the assembly of the peripheral portions of the two openings 7a and 7b.

  FIG. 6 is a diagram illustrating a process of assembling a check valve assembly from three parts, and FIG. 7 is a diagram illustrating a process of attaching the check valve assembly to the first opening.

  FIG. 8 is a view showing the state of assembling the filter and the rubber plug, FIG. 9 is a view showing the state of the ink filling operation, and FIG. 10 is a state where the second plug member is completely pushed into the second opening to seal the second communication path. It is a figure which shows a mode.

  FIG. 11 is a diagram showing how the protective film is attached to the cartridge housing. FIG. 12 is a view showing a state in which the protective film is fixed to the cartridge housing by heat welding.

  The ink cartridge of this embodiment employs a manufacturing process in which the check valve 3 is first assembled to form the check valve set 3x and then assembled to the cartridge housing 4. Therefore, first, the process of assembling the check valve assembly 3x will be described with reference to FIGS.

  First, in FIG. 6A, the stem 3b2 of the valve body 3b is inserted into the support hole 3a4 formed in the valve support member 3a, and the umbrella part 3b1 of the valve body 3b is attached to the inside of the valve support member 3a. To enter.

  A protrusion 3b3 is formed in the middle of the stem 3b2, and the portion of the protrusion 3b3 is slightly larger than the inner diameter of the support hole 3a4. However, as described above, the valve body 3b is made of silicon rubber. The protrusion 3b3 can be passed through the support hole 3a4 while being elastically deformed and compressed in the radial direction. Thus, once the valve body 3b is attached to the valve support member 3a as shown in FIG. 6B, the stem 3b2 is prevented from being removed from the support hole 3a4 by the projection 3b3. Is easy to handle when assembling.

  Next, as shown in FIG. 6B, the cover 3c is fitted and fixed to the valve support member 3a. Thus, the check valve set 3x is completed as shown in FIG.

  In the state of the check valve set 3x in FIG. 6C, the valve body 3b moves and can open and close the valve seat 3a3 so that the valve function can be exhibited. Therefore, by confirming whether or not the check valve 3 is operating correctly and adopting a manufacturing method in which only the check valve set 3x that has been confirmed to have no problem in operation is attached to the ink cartridge 1, The production yield of the ink cartridge 1 is improved.

  As a specific confirmation item of whether the check valve 3 operates, for example, the valve body 3b can move without being caught with respect to the valve support member 3a, or when the valve body 3b is closed, the valve seat 3a3 Are there any leaks between them?

  Next, the check valve assembly 3x is assembled to the first opening 7a of the cartridge housing 4 as shown in FIG.

  At this time, the stem 3b2 of the valve body 3b is pushed from the stem 3b2 to the bottom of the opening 7a so that the tip of the stem 3b2 faces the bottom of the opening 7a. The first opening 7a has a tapered shape that becomes slightly narrower toward the bottom in order to make fitting smoothly.

  Thus, as shown in FIG. 8, the check valve assembly 3x is arranged in contact with the bottom surface of the first opening 7a. In this state, the stem 3b2 of the valve body 3b is located inside the above-described first series passage 5a.

  As shown in FIG. 7, the first opening 7a has a smaller inner diameter near the bottom, and the side wall 3a2 of the valve support member 3a is closer to the outer periphery than the inner diameter near the bottom of the first opening 7a. The valve support member 3a is press-fitted into the bottom of the first opening 7a while plastically deforming the protrusion 3a7 or the inner surface near the bottom of the first opening 7a.

  In this insertion, as long as the stem 3b2 of the valve body 3b can be inserted into the first opening 7a with the check valve set 3x oriented in an appropriate direction, the check valve set 3x is no longer tilted and appropriate in this state. It will never be out of direction. Therefore, the check valve assembly 3x can be easily attached in an appropriate direction by pushing the check valve assembly 3x with an appropriate rod and pushing it into the bottom of the opening 7a. The effect of improving the assemblability based on the assembly of the check valve assembly 3x in advance to the housing 4 as described above is that the first opening 7a is a narrow and deep hole, or the valve body 3b is difficult to handle. It is particularly good when it is a small part.

  After the check valve 3 is disposed in the first opening 7a, as shown in FIG. 8, the filter 17 is inserted into the first opening 7a so as to contact the cover 3c of the check valve assembly 3x. Deploy. The filter 17 is for removing foreign matter in the ink supplied from the ink reservoir 2 to the inkjet head 45.

  Next, as shown in FIG. 8, the first plug member 6a and the second plug member 6b of the rubber plug 6 are fitted into the corresponding first opening 7a and second opening 7b.

  At this time, as shown in FIG. 9, the first plug member 6a is completely pushed into and fitted into the first opening 7a, while the second plug member 6b is completely pushed into the second opening 7b. Leave it in a slightly floating state. That is, the second stopper member 6b is in contact with the outer peripheral surface of the cylindrical portion 6x and the inner wall of the second opening 7b, and the projection 6z is at a position away from the second communication path 5b. Are fitted.

  This is because if the projection 6z seals the second communication path 5b, ink cannot be filled into the ink reservoir 2 through the second communication path 5b in the ink filling operation described later.

  Then, as shown in FIG. 9, the ink filling operation for the cartridge 1 is performed. The ink filling operation is performed using a dedicated ink filling device 50. The ink filling device 50 is inserted into the hollow air suction needle 51 inserted into the first opening 7a and the second opening 7b. The hollow ink filling needles 52 are arranged side by side.

  The air suction needle 51 is connected to a vacuum pump, while the ink filling needle 52 is connected to a large ink tank for filling.

  FIG. 9 shows a state where the cartridge 1 is mounted on the ink filling device 50. At this time, the air suction needle 51 passes through the blocking wall 6y of the first plug member 6a, and the ink filling needle 52 passes through the blocking wall 6y of the second plug member 6b. The positions of the openings 7a and 7b and the shapes of the plug members 6a and 6b are determined.

  Since the thickness t of the blocking wall 6y is thinner than the axial length h of the cylindrical portion 6x (t <h), even when the needles 51 and 52 are inserted into the blocking wall 6y, the blocking wall 6y passes through the blocking wall 6y. Even when the needles 51 and 52 are removed, the resistance is not so much generated. Therefore, it is easy to mount and remove the ink cartridge 1 on the ink filling device 50, and the two needles 51 and 52 are bent or damaged due to excessive force applied especially to the mounting. It is the structure which can avoid that.

  When the cartridge 1 is mounted on the ink filling device 50, the blocking wall 6y is in a position where it passes through the needles 51 and 52, and the cylindrical portion 6x is opened more than the blocking wall 6y. 7a and 7b are extended to the bottom side (the ink reservoir 2 side).

  Accordingly, the lengths of the two needles 51 and 52 are shorter than the axial length (the length h shown in FIGS. 4 and 9) of the cylindrical portion 6x of the corresponding plug member 6a and 6b of the rubber plug 6. Even so, if it is configured to have a length that can penetrate the thickness of the blocking wall 6y (similarly, the thickness t shown in the figure), the tips of both the needles 51 and 52 are connected to the bottoms of the corresponding openings 7a and 7b. The air can be sucked (or ink is injected) by facing the space on the side (communication passages 5a and 5b side).

  As described above, since the ink can be appropriately injected into the ink reservoir 2 without making the needles 51 and 52 so long, the manufacturing cost of the ink filling device 50 can be reduced.

  Further, it is advantageous in that the needles 51 and 52 are not easily bent when the cartridge 1 is attached to the ink filling device 50. That is, the needles 51 and 52 are required to have a small outer diameter (thick needles not only have excessive resistance when penetrating the rubber plug 6, but the holes of the penetrating holes are sealed with the plug members 6a and 6b themselves. In addition, since the interior must be hollow, there is a limit in strength, and it tends to bend. However, according to this configuration, it is sufficient to make the needles 51 and 52 slightly longer than the thickness t of the blocking wall 6y. Therefore, even the thin needles 51 and 52 can be hardly bent.

  When the vacuum pump is driven in the state of FIG. 9, the air accumulated in the ink reservoir 2 passes through the check valve 3 that is naturally opened by negative pressure from the first series passage 5a, and passes through the first opening 7a. Finally, it is sucked through the air suction needle 51 and discarded (evacuation). In the state where the inside of the ink reservoir 2 is depressurized, the ink passes from the ink tank for filling through the ink filling needle 52 and the second communication path 5b, and is filled into the ink reservoir 2. The ink filling is performed while measuring the filling amount until the film 2b swells as shown in FIG.

  Accordingly, air does not remain in the ink reservoir 2, the communication paths 5a and 5b, and the openings 7a and 7b, and the ink is filled. Thereafter, the cartridge 1 is removed from the ink filling device 50, and the two needles 51 and 52 are removed from the rubber stopper 6.

  Since the rubber stopper 6 is made of silicon rubber, the hole formed by passing through the two needles 51 and 52 is naturally sealed after the needles 51 and 52 are removed. It has become. Therefore, replacement of the rubber plug 6 with a new one and special work for sealing the hole are not required, and the number of manufacturing steps is reduced.

  In the ink filling operation of the present embodiment, the two needles 51 and 52 are simultaneously pierced into the rubber stopper 6 so that air suction and ink injection are performed simultaneously in parallel. The structure to perform may be sufficient.

  Specifically, first, only the air suction needle 51 is passed through the first stopper member 6a, and the vacuum pump is driven in this state to sufficiently depressurize the internal ink reservoir 2 to a level close to vacuum. Then, after the air suction needle 51 is removed from the first stopper member 6a, the ink filling needle 52 is passed through the second stopper member 6b and the ink is filled by the suction force due to the negative pressure in the ink reservoir 2. is there.

  At this time, since the hole formed in the first plug member 6a is naturally sealed by the penetration of the ink filling needle 52, the inflow of air from the first opening 7a is prevented. Further, even if air flows in through the hole of the penetrating trace of the ink filling needle 52 of the first plug member 6a, the check valve 3 prevents the air from flowing to the ink reservoir 2 side. Become.

  When the air suction needle 51 is inserted into the first opening 7a in the ink filling operation, the air suction needle 51 is excessively formed in the opening portion as shown by a chain line in FIG. The possibility of getting into the back is not zero.

However, in this configuration, the cover 3c is disposed on the first plug member 6a side of the check valve 3, and therefore, when the tip of the air suction needle 51 comes into contact with the cover 3c, there is no further penetration into the back. It is blocked by the cover 3c. Therefore, the air suction needle 51 is prevented from reaching the check valve 3, and damage to the check valve 3 is avoided. As a result, the manufacturing yield is improved.

  The cover 3c is formed with a receiving surface 3c2 at the center of the outer surface (that is, the portion corresponding to the air suction needle 51), and the filter 17 is in contact with the receiving surface 3c2. Is provided. Therefore, even when the air suction needle 51 is excessively inserted into the interior for some reason as described above, the pointed portion of the tip of the air suction needle 51 penetrates the filter 17 and simultaneously contacts the receiving surface 3c2. Further entry of the air suction needle 51 is prevented by the receiving surface 3c2. Accordingly, it is possible to prevent the thick portion of the air suction needle 51 from penetrating the filter 17 and making a large hole in the filter 17, and as a result, the function of the filter 17 is prevented from being impaired.

  After that, as shown in FIG. 10, the second stopper member 6b of the rubber stopper 6 is completely pushed into the second opening 7b, and the opening formed by the second communication path 5b at the bottom of the second opening 7b is formed as the protrusion described above. Seal with 6z.

  That is, the second plug member 6b has a position where the protrusion 6z is separated from the second communication path 5b and the communication path is opened, and a position where the protrusion 6z is in close contact with the second communication path 5b and the communication path is sealed. In addition, it is movable in the axial direction of the second opening 7b.

  The protrusion 6z allows the ink to flow from the plug member 6b side to the ink reservoir 2 side in the ink filling operation described above. On the other hand, after the ink filling operation is completed, the protrusion 6z It serves as a valve part or valve member that prevents flow.

  In other words, when the second plug member 6b is completely fitted into the second opening 7b, the first sealing action by the close contact between the outer peripheral surface of the cylindrical portion 6x and the inner wall of the second opening 7b, and The second sealing action by the close contact between the protrusion (the above-described valve) 6z and the end of the second communication passage 5b is performed. Therefore, air or the like enters the ink reservoir 2 from the second opening 7b through the second communication path 5b by the double sealing action, or the second from the ink reservoir 2 through the second communication path 5b. Ink leakage from the opening 7b can be prevented more reliably.

  Finally, as shown in FIG. 11, a protective film 18 having a “U” shape formed by bending both ends of the thin plate to the same side covers the two openings 7a and 7b with the rubber plug 6 fitted thereto. The cartridge housing 4 is fixed. Although the cross-sectional structure of the protective film 18 is not shown, a polypropylene layer that is the same material as the cartridge housing 4 and a polyethylene terephthalate (PET) layer that has higher heat resistance than polypropylene are integrally laminated. It has a two-layer structure.

  Then, this polypropylene layer is attached to the cartridge housing 4 with the inner surface facing, and a heater is applied from the outside as shown in FIG. 12, so that the polypropylene layer is welded and fixed to the cartridge housing 4. Yes.

  By doing so, it is possible to reliably prevent the rubber stopper 6 from coming out of the openings 7a and 7b during handling of the cartridge. Further, even if the ink leaks from the gap between the rubber plug 6 and the openings 7a and 7b, the protective film 18 can prevent the ink from leaking to the outside of the cartridge housing 4. .

  Thus, since the inner surface side of the protective film 18 is made of polypropylene, when heated with a heater as shown in FIG. 12, it melts and adheres well to the cartridge housing 4 which is also made of polypropylene, and is integrated. Thus, it is possible to reliably prevent ink leakage.

  Narrow grooves 9 and 9 are formed in the cartridge housing 4 at two locations across the two openings 7a and 7b. When the protective film 18 is fixed to the cartridge housing 4, both ends of the “U” -shaped protective film 18 enter the narrow grooves 9 and 9, respectively.

  In other words, the end of the protective film 18 enters the inside of the cartridge housing 4. Therefore, the end portion of the protective film 18 is not exposed to the outside during handling of the cartridge 1, and it can be reliably prevented that the protective film 18 is peeled off from the end portion even when an external force or the like is applied.

  Further, as shown in FIG. 4B and FIG. 12, the end of the cartridge housing 4 on the side where the openings 7a and 7b are formed has a portion where the protective film 18 is attached more appropriately than the other portions. It has a configuration protruding by a height g. Further, the portion where the protective film 18 is attached in the cartridge housing 4 is formed in a flat plane shape except for the portion where the rubber plug 6 is located.

  Therefore, when a heater having a flat heating surface is applied, only the portion to which the protective film 18 of the cartridge housing 4 is attached can be sufficiently heated, and adhesion can be ensured. Further, since the portion other than the protective film 18 mounting portion is located away from the heating surface by the height g, it does not melt unnecessarily and does not impair the appearance of the cartridge 1.

  In addition, as a structure welded by heat, in addition to the above-described heater (heating and melting apparatus), a melting apparatus using ultrasonic waves can also be used.

[Configuration of the connection between the ink cartridge and the device]
Next, how the ink cartridge 1 formed as described above is attached to the cartridge mounting portion 14 of the multifunction machine 30 will be described with reference to the schematic diagram of FIG. 2 and FIG.

  FIG. 13 is a diagram illustrating a state in which the ink cartridge is attached to the cartridge mounting portion of the apparatus.

  As shown in FIG. 13, the hollow needle 8 provided in the cartridge mounting portion 14 penetrates the protective film 18 and the first plug member 6a when the ink cartridge 1 is mounted on the mounting portion 14. . The tip of the hollow needle 8 is located between the filter 17 and the inner surface of the closing wall 6y of the first plug member 6a.

  With this configuration, the ink in the ink reservoir 2 passes through the check passage 3 via the communication path 5a, enters the inside through the opening at the tip of the hollow needle 8, and passes through the tube 41 (FIG. 2). The recording head unit 42 is supplied.

  When the cartridge housing 4 is attached to the apparatus side, the hollow needle 8 for sucking ink from the ink reservoir 2 passes through the blocking wall 6y of the first stopper member 6a. The positions of the hollow needle 8 and the first opening 7a are determined.

  Further, as described above, the thickness t of the blocking wall 6y is thinner than the axial length h of the cylindrical portion 6x (t <h). Therefore, in the same manner as in the case of the two needles 51 and 52 of the ink filling device 50, when the hollow needle 8 is plunged into the blocking wall 6y, the hollow needle 8 that has penetrated the blocking wall 6y is removed. When removing, resistance is not so much generated. Therefore, the operation of mounting the ink cartridge 1 to the cartridge mounting portion 14 is easy, and it is also possible to avoid bending or bending of the hollow needle 8 due to excessive force applied during mounting. .

  Further, since the rubber stopper 6 is made of silicon rubber, the hole formed by the hollow needle 8 can be removed by removing the hollow needle 8 after the hollow needle 8 has passed through the rubber stopper 6. Can be sealed by the rubber plug 6 itself. Therefore, even when the cartridge 1 once attached to the mounting part 14 is removed for some reason, the trace hole that has penetrated the hollow needle 8 is sealed, so that ink leakage is avoided.

  In addition, as in the case of the ink filling device 50 described above, the blocking wall 6y of the first stopper member 6a penetrates the hollow needle 8 when the cartridge 1 is mounted on the cartridge mounting portion 14. Is in a position. Further, the cylindrical portion 6x of the first plug member 6a extends to the bottom side (the ink reservoir 2 side) of the opening 7a from the blocking wall 6y.

  Accordingly, the length of the hollow needle 8 is such that it can penetrate the thickness of the blocking wall 6y of the corresponding first plug member 6a of the rubber plug 6 (thickness t shown in FIGS. 4 and 13). If configured, the tip of the hollow needle 8 is made to face the space on the bottom side of the opening 7a (communication path 5a side) even if it is shorter than the axial length (similarly, the length h shown in the figure) of the cylindrical portion 6x. The ink in the ink reservoir 2 can be supplied to the recording head unit 42 side through the hollow needle 8.

  As described above, since the ink can be appropriately supplied from the ink reservoir 2 to the recording head unit 42 without making the hollow needle 8 too long, the manufacturing cost of the cartridge mounting portion 14 can be reduced.

  Further, it is advantageous in that the hollow needle 8 is difficult to bend when the cartridge 1 is mounted on the mounting portion 14. That is, the hollow needle 8 is required to be thin like the above-described needles 51 and 52, and is easy to bend because it is hollow, but if this configuration is used, the hollow needle 8 does not have to be long. Therefore, even if it is the thin hollow needle 8, it can be set as the structure which does not bend easily.

  The second communication path 5b communicates with the second opening 7b at a position eccentric with respect to the central axis of the second opening 7b. Therefore, even if the hollow needle 8 is penetrated to the second opening 7b side due to some circumstances such as an erroneous operation, the projection 6z portion further penetrates the thick portion of the cylindrical portion 6x of the second plug member 6b. Unless extreme things are made to penetrate, the tip of the hollow needle 8 does not reach the second communication path 5b.

  In other words, even if such an erroneous operation is performed, it is possible to reliably prevent external air and impurities from entering the ink reservoir 2.

  Although the basic embodiment has been described above, the configuration of the protrusion 6z (valve portion) that closes the second communication path 5b of the ink cartridge 1 can be variously modified.

  Hereinafter, first to third modifications will be described.

[First modification]
In the first modification, as shown in FIG. 14 (a), the protrusion 6z formed on the second plug member 6b is not pointed as shown in FIG. 8, and the tip side has a considerable thickness. The protrusion 6z ′ has a shape. In addition, unlike the above-described basic embodiment, the protrusion 6z ′ is configured to be formed at the center of the bottom surface of the second plug member 6b. Correspondingly, the position where the second communication path 5b is formed is determined so as to be connected to the center of the inner bottom surface of the second opening 7b.

  FIG. 14B shows the ink filling operation in this configuration. At this time, the second stopper member 6b is not completely fitted into the second opening 7b, and the protrusion 6z ′ is separated from the second communication path 5b. The second communication path 5b is opened. Therefore, the flow of ink from the plug member 6b side to the ink reservoir 2 side is allowed.

  In this state, the ink filling needle 52 can be filled with ink by passing through the position of the plug member 6b avoiding the projection 6z 'formation portion.

  After completion of the ink filling operation, as shown in FIG. 14C, the second plug member 6b is completely pushed in the axial direction of the second opening 7b so that the protrusion 6z ′ is inserted into the second communication path 5b. . Since the projection 6z ′ has an outer diameter slightly larger than the inner diameter of the second communication path 5b, the protrusion 6z ′ is pushed into the second communication path 5b while being compressed and deformed, and its outer periphery is the second communication path. The second communication path 5b is sealed by being in close contact with the inner wall of 5b (FIG. 14 (d)).

  As a result, the flow of ink from the plug member 6b side to the ink reservoir 2 side is blocked, so that the entry of impurities / bubbles into the ink reservoir 2 can be avoided. Further, in the state of FIG. 14D, even if the user accidentally pierces the second plug member 6b and penetrates the needle toward the second communication passage 5b, it is compressed and increased in hardness. Since it is very difficult for the needle to penetrate the protruding portion 6z ′, it is possible to prevent the entry of impurities / bubbles into the ink reservoir 2 due to such an error.

[Second modification]
As shown in FIG. 15 (a), the second modified example is the first modified example in which a cut 74 is formed from one side at the base portion of the protrusion 6z ′. The second communication path 5b ′ connects the ink reservoir 2 and the second opening 7b while appropriately forming a curved shape. Other configurations are the same as those of the first modification described above.

  In this configuration, as shown in FIG. 15D, when the second stopper member 6b is completely pushed into the second opening 7b and the protrusion 6z ′ enters the second communication path 5b ′, the protrusion 6z ′ becomes the second communication path. Bent along 5b '.

  In the state of FIG. 15D, even if the user accidentally pierces the second stopper member 6b and tries to penetrate the needle toward the second communication passage 5b, the bent portion of the second communication passage 5b ′. In addition, since it is very difficult to reach the tip of the needle through the protrusion 6z ′ which has been compressed and has increased strength as described above, impurities / bubbles to the ink reservoir 2 due to such an error can be obtained. Intrusion can be prevented beforehand.

  If the user accidentally pulls out the second stopper member 6b, the projection 6z ′ is torn off from the base incision 74 and remains in the second communication path 5b ′. The closed state is ensured, impurities and bubbles are prevented from entering the ink reservoir 2, and the ink in the ink reservoir 2 can be prevented from being scattered from the opening 7b and contaminating the surroundings.

  In addition to the configuration for forming the notch 74, various variations are conceivable. In short, the root portion of the protrusion 6z ′ is weakened in some form, and the protrusion 6z ′ is easily destroyed at that portion. Any shape can be used. For example, it may be possible to make the root portion thin.

[Third Modification]
In the third modification, as shown in FIG. 16A, the second communication path 5b "is formed not on the inner bottom surface of the second opening 7b but on the side surface. The second communication path 5b" The ink reservoir 2 is connected to the ink reservoir 2 while having an appropriate curved shape. On the other hand, no protrusion is formed on the second plug member 6b. Therefore, in this third modification, the side surface portion of the second plug member 6b serves as the valve member.

  In this configuration, when the second plug member 6b is completely fitted as shown in FIG. 16D, the user accidentally pierces the second plug member 6b from the outside toward the second communication path 5b ″. Even if it tries to penetrate, it is very difficult to penetrate the second stopper member 6b obliquely and reach the tip of the needle to the second communication path 5b ″. Accordingly, it is possible to prevent impurities and bubbles from entering the ink reservoir 2 due to such an error.

  Although the first to third modifications have been described above, the states of (a), (b), and (c) are the valve portions of the second plug member 6b through FIGS. Is a state in which the communication passage is opened away from the second communication passages 5b, 5b ′, 5b ″, and the state of FIG. Is in a state of sealing the communication path.

  That is, in the above three modified examples, the second stopper member 6b is moved in the axial direction of the second opening 7b, so that the positions shown in (a), (b), and (c) in FIG. It can be moved.

  Accordingly, in the state of (b), the ink can be properly filled, while in the state of (d), the entry of impurities and bubbles into the ink reservoir 2 can be prevented.

1 is a side view showing an overall configuration of a multifunction machine to which the present invention is applied. FIG. 2 is a schematic diagram illustrating a connection configuration between an ink cartridge and a recording head, and a purge mechanism. FIG. 3 is a partial cross-sectional view of a plan view illustrating a specific configuration of an ink cartridge. (A) is a partial cross-sectional perspective view of a rubber plug, (b) is a perspective view showing a configuration of a peripheral portion of two openings of a cartridge housing. The enlarged view of the part enclosed with the circle | round | yen of FIG. 3 which shows the detail of the non-return valve installed in opening. The figure which shows the mode of the process of assembling a non-return valve assembly from three components. The figure which shows the mode of the process of attaching a non-return valve group to a 1st opening. The figure which shows a mode that a filter and a rubber stopper are assembled | attached. The figure which shows the mode of an ink filling operation | work. The figure which shows a mode that a 2nd plug member is fully pushed in to 2nd opening, and a 2nd communicating path is sealed. The figure which shows a mode that a protective film is attached to a cartridge housing. The figure which shows a mode that a protective film is welded and fixed to a cartridge housing with a heat | fever. FIG. 4 is a diagram illustrating a state where an ink cartridge is attached to a cartridge mounting portion of the apparatus. The figure which showed the process from the filling of an ink to an apparatus in the ink cartridge of a 1st modification. The figure which showed the process from the filling of an ink to attachment to an apparatus in the ink cartridge of a 2nd modification. The figure which showed the process from the filling of an ink to an apparatus in the ink cartridge of a 3rd modification.

Explanation of symbols

1 Ink cartridge 2 Ink reservoir 4 Cartridge housing 5b Second communication path (communication path)
6b Second plug member (plug member)
6z protrusion (valve part)
7b Second opening (opening)
8 Hollow needle

Claims (5)

A cartridge housing having an ink reservoir for containing ink; an opening provided in the cartridge housing to be opened to the outside; and an opening communicating with the ink reservoir through a communication path; A plug member having elasticity that can penetrate the needle and that can be sealed by itself after removing the hollow needle, and a valve portion that is provided in a part of the plug member and that can seal the communication passage. An ink cartridge comprising the ink cartridge. 2. The ink cartridge according to claim 1, wherein the plug member is fitted in the opening so as to be movable between a position where the valve portion opens the communication path and a sealable position. Ink cartridge. The ink cartridge according to claim 2, wherein the communication path communicates with the opening at a position eccentric with respect to a central axis of the opening, and the plug member separates the valve portion from the communication path. An ink cartridge that is movable in the axial direction of the opening between a position where the communication path is opened and a position where the valve portion is in close contact with the communication path to seal the communication path. The ink cartridge according to claim 2, wherein the valve portion is formed to protrude from the plug member, and the plug member separates the valve portion from the communication path and opens the communication path; An ink cartridge which is movable in the axial direction of the opening to a position where the valve portion is fitted into the communication path to seal the communication path. A cartridge housing having an ink reservoir for containing ink; an opening provided in the cartridge housing to be opened to the outside; and an opening communicating with the ink reservoir through a communication path; A plug member having elasticity that can penetrate the needle and that can be sealed by itself after removing the hollow needle, and a valve portion that is provided in a part of the plug member and that can seal the communication passage. An ink cartridge filling method for an ink cartridge comprising:
With the plug member fitted in the opening at a position where the valve portion opens the communication path, the hollow needle penetrates the plug member, and the ink reservoir is filled with ink through the hollow needle. Thereafter, the plug member is moved to a position where the valve portion seals the communication path.