Method of filling ink cartridge with ink

A method of filling an ink cartridge with ink, the ink cartridge being to be mounted on a main body of a recording apparatus and including: a casing in which is formed an ink chamber for accommodating ink; and at least one valve member which is disposed on one side of the casing and which is biased, in an ordinary state, in a direction to close at least one communication passage through which the ink chamber communicates with an exterior of the ink cartridge, the at least one valve member being arranged to be placed in an open state when the ink cartridge is mounted on the main body of the recording apparatus, the method including: forming, at a portion of the casing except for the one side thereof on which the valve member is disposed, an opening through which the ink chamber and the exterior of the ink cartridge communicate with each other; and filling the ink cartridge with ink by introducing the ink into the ink chamber through the opening.

The present application is based on Japanese Patent Application No. 2004-184450 filed on Jun. 23, 2004, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates in general to a method of filling an ink cartridge with ink.

2. Discussion of Related Art

As disclosed in U.S. Pat. No. 6,786,581 B1, US 2002/060725 A1, and US 2004/233260 A1 corresponding to JP-A-2001-113723, an ink cartridge is installed on an ink-jet recording apparatus and ink in the ink cartridge is consumed in accordance with print operation performed by the ink-jet recording apparatus. When the ink in the ink cartridge is completely consumed, the ink cartridge which has been used is replaced with a new ink cartridge purchased by a user and the used ink cartridge is discarded. The discard of the used ink cartridge, however, undesirably results in environmental contamination and wasteful consumption of finite resources on the earth. Accordingly, there is a demand for recycling of the used ink cartridge. An ink cartridge disclosed in the above-indicated US documents is provided with a valve device which is kept in its closed state in an ordinary condition by means of a spring. When the ink cartridge is mounted on a recording apparatus, the valve device is placed in its open state, whereby ink in the ink cartridge is supplied to the recording apparatus. Where the ink in the ink cartridge is used up, the ink cartridge can be filled with ink through the valve device by placing the valve device in its open state. For placing the valve device in its open state with high reliability, however, it is required to use a jig suitable for the valve device.

SUMMARY OF THE INVENTION

The present invention has been developed in the light of the situations described above. It is therefore an object of the present invention to provide a method of easily filling an ink cartridge with ink.

The object indicated above may be achieved according to a principle of the invention, which provides a method of filling an ink cartridge with ink, the ink cartridge being to be mounted on a main body of a recording apparatus and including: a casing in which is formed an ink chamber for accommodating ink; and at least one valve member which is disposed on one side of the casing and which is biased, in an ordinary state, in a direction to close at least one communication passage through which the ink chamber communicates with an exterior of the ink cartridge, the at least one valve member being arranged to be placed in an open state when the ink cartridge is mounted on the main body of the recording apparatus, the method comprising: forming, at a portion of the casing except for the one side thereof on which the valve member is disposed, an opening through which the ink chamber and the exterior of the ink cartridge communicate with each other; and filling the ink cartridge with ink by introducing the ink into the ink chamber through the opening.

According to the present method described above which comprises a step of forming the opening that permits communication between the ink chamber and the exterior of the ink cartridge at a portion of the casing except for the one side thereof on which the valve member is disposed, the opening can be easily formed in the casing using a commercially available tool such as a drill, without being disturbed by the valve member, so that the ink can be introduced through the opening.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to the drawings, there will be described a preferred embodiment of the present invention. Various aspects of the present invention may be used with the filling and/or refilling of an ink cartridge.FIG. 1is a schematic view of an ink cartridge1and an ink-jet recording apparatus2on which the ink cartridge1is mounted.

The ink-jet recording apparatus2includes: a mounting portion3on which the ink cartridge1is removably mounted and which partially constitutes a main body of the recording apparatus2; an ink tank5for storing ink to be supplied from the ink cartridge1via an ink supply tube4; a recording head7for ejecting the ink stored in the ink tank5toward a recording medium6; a carriage9by which is carried a head unit8including the ink tank5and the recording head7and which linearly reciprocates; a carriage shaft10which guides the reciprocating movement of the carriage9; a sheet feeding mechanism11for feeding the recording medium6; and a purging device12.

The ink cartridge1is provided for each of a plurality of different colors of inks such as cyan, magenta, yellow, black, etc., and is mounted on the ink-jet recording apparatus2for enabling the recording apparatus2to perform color printing operation.

The mounting portion3includes a base portion3aand guide portions3b,3bwhich extend from opposite ends of the base portion3a. A hollow ink-supplying pipe13and a hollow air-introducing pipe14are disposed so as to protrude from the base portion3awhich is interposed between the guide portions3b,3b. The ink-supplying pipe13is for extracting the ink stored in the ink cartridge1and the air-introducing pipe14is for introducing air into an interior of the ink cartridge1. Each of the ink-supplying pipe13and the air-introducing pipe14has, at a top end thereof, a generally flat surface. The ink-supplying pipe13and the air-introducing pipe14respectively have, at respective upper end portions thereof, communication openings13aand communication openings14aeach in the form of a cutout.

The ink supply tube4is connected to one of opposite ends of the ink-supplying pipe13, so that the ink-supplying pipe13communicates with the ink tank5via the ink supply tube4. An air-introduce tube15is connected to one of opposite ends of the air-introducing pipe14, so that the air-introducing pipe14communicates with outside air via the air-introduce tube15.

The recording head7includes: a cavity plate (not shown) which is formed by superposing a plurality of plates and to which the ink is supplied from the ink tank5; and a piezoelectric actuator plate (not shown) which has a plurality of piezoelectric deforming portions and which is formed to have a plate-type structure. The cavity plate and the piezoelectric actuator plate are bonded to each other so as to constitute the recording head7. For ejecting the ink, a CPU (not shown) outputs drive signals to the respective piezoelectric deforming portions. The piezoelectric deforming portions into which the drive signals have been inputted deform, whereby the ink is jetted from nozzles (not shown) corresponding respectively to the deformed piezoelectric deforming portions. The nozzles are arranged in zigzag fashion on a surface of the recording head7that faces the recording medium6.

The purging device12is located outside a recording area so as to be opposed to the recording head7. The purging device12has a purge cap12afor closing the surface of the recording head7in which the nozzles are formed, a waste-ink tube12bwhich communicates with the purge cap12a, and a pump12cfor sucking poor-quality or waste ink from the nozzles via the waste-ink tube12b.

By referring next toFIG. 2, there will be explained a structure of the ink cartridge1. The ink cartridge1has a casing in which is formed an ink chamber20that is a space for accommodating the ink. The casing is constituted by: a casing body1bwhich gives a bottom wall21and a circumferential wall22of the ink chamber20and which has an upper opening; and a lid member1awhich closes the upper opening of the casing body1b. To the thus constituted casing, a cover member1cis fixed so as to clover the bottom wall21of the casing body1b. The cover member1cis formed with two end holes23,24through which respective valve devices27,28(that will be described) are exposed to the exterior of the ink cartridge1on the mounting-portion side. The lid member la and the cover member1care bonded or welded to the casing body1b, thereby providing the ink cartridge1. In the present embodiment, the lid member1a, the casing body1b, and the cover member1care formed of a resin material such as polypropylene, polystyrene, or polyacetal.

The bottom wall21is formed with an ink-supply hole25which is open for supplying the ink in the ink chamber20to the exterior. The ink-supply hole25is defined by interior space of a cylindrical wall25awhich is formed integrally with the bottom wall21so as to protrude from the lower surface of the same21. The bottom wall21is further formed with an air-introduce hole26which is open for introducing the outside air into the ink chamber20. The air-introduce hole26is defined by interior space of a cylindrical wall26awhich is formed integrally with the bottom wall21so as to protrude from the lower surface of the same21. When the ink cartridge1is installed on the mounting portion3, the ink-supplying pipe13is inserted into the ink-supply hole25while the air-introducing pipe14is inserted into the air-introduce hole26.

Within the cylindrical wall25athat defines the ink-supply hole25, the valve device27is disposed so as to inhibit communication between the interior and the exterior of the ink cartridge1. Within the cylindrical wall26athat defines the air-introduce hole26, the valve device28is disposed so as to inhibit communication between the interior and the exterior of the ink cartridge1. The valve devices27,28will be explained in greater detail.

The bottom wall21is formed with a plurality of communication holes30through which the ink-supply hole25and the ink chamber20communicate with each other. At a central position surrounded by the plurality of communication holes30, there is formed a through-hole31in which is inserted a check valve32having a generally umbrella-like shape. The check valve32is formed of an elastic resin material having elasticity.

As shown inFIG. 2, the check valve32consists of a disc-like portion33having elasticity and located on one of opposite sides of the bottom wall21nearer to the ink-supply hole25so as to oppose to the bottom wall21; and a shaft portion34which extends from a substantially central part of the disc-like portion33toward the ink chamber20through the through-hole31. The shaft portion34includes a ball portion35which has a generally ball-like shape and whose diameter is larger than an inside diameter of the through-hole31. The shaft portion34is supported in the through-hole31so as to be slidable between a position at which the movement of the shaft portion34is stopped by the disc-like portion33and a position at which the movement of the shaft portion34is stopped by the ball portion35.

On the bottom wall21, there is formed a hollow cylindrical air-introduce member40which extends from the bottom wall21in an upward direction toward the upper opening of the casing body1band which is formed integrally with the bottom wall21. The air-introduce member40has an upper end opening42that is open above the surface of the ink in the ink chamber20. The air-introduce member40communicates at its lower end portion with the air-introduce hole26and has an inner flow passage41through which the air is introduced into the ink chamber20.

Next, there will be explained the valve device27disposed in the ink-supply hole25and the valve device28disposed in the air-introduce hole26. The valve device27includes: a support member50which is an integral body provided by a rubber-like elastic member; and a valve member51formed of a resin material. The support member50has a generally cylindrical outer profile and is integrally constituted by including: a valve seat portion52which is located at a substantially middle portion of the support member50as seen in its center axis direction; a bias portion53which is located on one of opposite sides of the valve seat portion52nearer to the ink chamber20; a cylindrical portion54which extends from the valve seat portion52so as to be located on the other of the opposite sides of the valve seat portion52remote from the ink chamber20; and an outer cylindrical wall55which is located radially outwardly of the cylindrical portion54with a spacing therebetween and which extends in parallel with the cylindrical portion54. The valve member51is accommodated within the bias portion53while being biased by the same53in a direction in which the valve member51abuts on the valve seat portion52.

The outer cylindrical wall55has a positioning portion56which protrude therefrom in a radially outward direction. The ink-supply hole25has, at its open end, a large-diameter portion If having a diameter larger than the other portion (small-diameter portion) thereof, for accommodating the positioning portion56. With the positioning portion56pressed and gripped by an between the large-diameter portion if and the cover member1c, the casing body1band the cover member1care bonded or welded together, thereby preventing the ink from leaking from between the casing body1band the valve device27.

The valve seat portion52has an opening58formed at its central portion through the thickness thereof in its center axis direction. The cylindrical portion54has a guide passage59into which the ink-supplying pipe13is inserted when the ink cartridge1is mounted on the mounting portion3. The cylindrical portion54is formed integrally with and adjacent to the valve seat portion52with the guide passage59held in communication with the opening58. The guide passage59is arranged to have an inside diameter smaller than an outside diameter of the ink-supplying pipe13for permitting the ink-supplying pipe13inserted thereinto to be brought into close contact with the inner wall of the cylindrical portion54defining the guide passage59. The opening58has a size which is larger than the inside diameter of the guide passage59and the outside diameter of the ink-supplying pipe13. The inside diameter of the guide passage59gradually increases, at one end thereof nearer to the exterior of the ink cartridge1, in a direction away from the opening58.

The cylindrical portion54and the outer cylindrical wall55are spaced apart from each other by an annular groove60, and the cylindrical portion54is arranged to be elastically deformed in a plane perpendicular to the center axis direction of the guide passage59. The bias portion53is constituted by including: a cylindrical side wall portion61which extends from the periphery of the valve seat portion52toward the ink chamber20; and an inwardly-extending portion62which is formed adjacent to the cylindrical side wall portion61and which extends radially inwardly so as to abut on one end of a cylindrical valve wall71of the valve member51(which will be described), which one end is located nearer to the ink chamber20. The inwardly-extending portion62has a central opening63formed at its central portion. The bias portion53biases, by elasticity of the cylindrical side wall portion61and the inwardly-extending portion62, the valve member51in a direction in which the valve member51abuts on the valve seat portion52. In an ordinary state, the bias portion53biases the valve member51such that the valve member51is held in close contact with the valve seat portion52. When the valve member51is pushed up toward the ink chamber20upon insertion of the ink-supplying pipe13into the guide passage59, the cylindrical side wall portion61is stretched and the inwardly-extending portion62is inclined, to thereby form a clearance between the valve member51and the valve seat portion52for an ink flow.

The valve member51has a bottom portion70which abuts on the valve seat portion52of the support member50and the cylindrical valve wall71which extends from the periphery of the bottom portion70toward the ink chamber20. The bottom portion70has, on one of its opposite surfaces which faces the valve seat portion52, an annular protruding portion72which protrudes toward the valve seat portion52and which is formed at a position located radially inwardly of the cylindrical valve wall and radially outwardly of the guide passage59. In a state in which the valve member51is accommodated within the support member50, the cylindrical valve wall71of the valve member51is held in close contact with and pressed against the lower surface of the inwardly-extending portion62of the bias portion53, whereby the annular protruding portion72of the valve member51closely contacts the upper surface of the valve seat portion52by elastically deforming the same52. Thus, the guide passage59is fluid-tightly closed with respect to the ink chamber20.

A plurality of communication passages73are formed such that each communication passage73is located radially outwardly of the protruding portion72of the bottom portion70and extends into the cylindrical valve wall71. Through the communication passages73, the upper portion of the valve member51nearer to the ink chamber20and the lower portion thereof remote from the ink chamber20communicate with each other. The communication passages73are formed so as to be spaced apart from each other with a constant spacing distance in the circumferential direction of the bottom portion70.

The valve device28is substantially identical in construction with the valve device27. The same reference numerals used for the components of the valve device27are used to identify the corresponding components of the valve device28and a detailed explanation of which is dispensed with. The valve device28has a valve member81which includes: a bottom portion90, a cylindrical valve wall91, an annular protruding portion92, and communication passage93, which are similar to the corresponding components of the valve member51. The valve device28further has a projecting portion94which is formed at a generally central portion of the upper surface of the bottom portion90and which projects toward the ink chamber20farther than the cylindrical valve wall91. The projecting portion94is inserted through the opening63of the bias portion53with a spacing interposed therebetween and projects toward the air-introduce member40.

When the ink cartridge1is mounted on the mounting portion3(in a direction indicated by an arrow “X” inFIG. 1), the ink-supplying pipe13and the air-introducing pipe14are inserted into the respective guide passages59while deforming the respective cylindrical portions54such that the diameter thereof increases, and the two pipes13,14are brought into abutting contact respectively with the bottom portion70,90of the valve member51and the valve member81. Thereafter, when the ink cartridge1is further pushed in the above-indicated X-direction, the valve members51,81are pushed toward the ink chamber20(i.e., moved in a direction away from the respective valve seat portions52), so that there are formed an air-introduce passage86in the valve device28for introducing the air into the interior of the ink cartridge1and an ink-supply passage85in the valve device27for supplying the ink from the ink cartridge1to the exterior thereof. The ink cartridge1is packed such that the interior thereof is kept under reduced pressure. Accordingly, where the air-introduce passage86and the ink-supply passage85are formed at substantially the same time, the air tends to flow from the air-introducing pipe14toward the ink chamber20and the ink remaining in a flow passage between the ink-supplying pipe13and the recording head7tends to flow from the ink-supplying pipe13toward the ink chamber20. However, the check valve32inhibits the remaining ink from flowing back into the ink chamber20, and the air rapidly flows into the upper portion of the ink chamber20from the air-introducing pipe14via the inner flow passage41of the air-introduce member40.

In an ordinary state, the check valve32is placed, by its self-weight, in a position where the disc-like portion33is spaced apart from the communication holes30, whereby the ink is supplied from the ink chamber20to the recording head7via the communication holes30, the communication passages73of the valve member51, and the ink-supplying pipe13. As the ink flows out of the ink chamber20, the air is supplied to the upper portion of the ink chamber20from the air-introducing pipe14via the inner flow passage41of the air-introduce member40. In this instance, the upper end of the projecting portion94of the valve device28disposed within the air-introduce hole26is positioned such that it is spaced apart from the lower end of the inner flow passage41, so as to assure the air-flow toward the ink chamber20.

In a case where the ink stored in the ink chamber20of the ink cartridge1is consumed by printing operation, it is desirable to fill the ink cartridge1with ink.

The ink cartridge1is filled with the ink in the following method: As shown inFIG. 3A, an opening103for permitting communication between the ink chamber20and the exterior is formed in the casing which constitutes the ink chamber20, and the ink is introduced into the ink chamber20through the opening103using an ink-injector100. The opening103is formed preferably at a portion of the lid member la or a portion of the circumferential wall22of the casing body1b, except for the cover member1cfixed to one side of the casing for holding the valve devices27,28. It is particularly preferable to form the opening103in the upper surface of the lid member1aexcept for a gripping protrusion1a-1thereof since that upper surface is flat. The reasons because it is not preferable to form the opening103in the cover member1care as follows: It is difficult to form the opening103in the cover member1csince the valve devices27,28and the walls for accommodating the same27,28are present in the cover member1c. Further, the formation of the opening103in the cover member1cmay cause a risk of breaking or destroying the valve devices27,28.

The ink-injector100includes a container portion100aformed of a flexible material and accommodating the ink and a tube-like nozzle portion100bextending form the container portion100a. The nozzle portion100bhas, at its leading end, an outside diameter that is equal to or smaller than an inside diameter of the opening103formed in the casing. The nozzle portion100bis inserted into the opening103and the container portion100ais compressed, whereby the ink in the container portion100ais introduced into the ink chamber20. There may be employed, as the container portion100a, a syringe-like device constituted by a cylinder and a piston.

The opening103is formed using a commercially available tool such as a drill101shown inFIG. 3B. Preferably, as shown inFIG. 3A, two openings103are formed, and the ink is introduced through one of the two openings103while the air in the ink chamber20is discharged through the other of the two openings103, so that the ink cartridge1can be efficiently and quickly filled with the ink. The resin material for the ink chamber20is transparent or translucent. Accordingly, the introduction of the ink into the ink chamber20can be performed while visually checking the amount of the ink introduced into the ink chamber20, and the introduction of the ink is stopped before the surface level of the ink in the ink chamber20reaches a level of the upper end opening42of the air-introduce member40.

After the ink cartridge1has been filled with the ink, the opening103is fluid-tightly closed by fitting, in the opening103, a plug102having a shape as shown inFIG. 3C. The plug102is formed of an elastic body such as rubber, and has a shaft portion and end portions which are respectively formed at opposite ends of the shaft portion and which have respective diameters that are larger than the diameter of the opening103. The plug102is closely fitted in the opening103and the end portions thereof are brought into close contact with opposite surfaces of a wall which constitutes the casing, whereby the opening103can be completely and easily closed. The opening103may be fluid-tightly closed using an adhesive tape, a seal tape, or the like. The opening103is fluid-tightly closed to prevent: a change in the concentration of the ink due to evaporation of the aqueous component in the ink; ink-ejection failure due to entering of foreign matter; and leakage of the ink from the ink cartridge1during carrying of the same1.

As described above, according to the present method of filling the ink cartridge with the ink, the opening103is formed in the casing except for the cover member1cwhich is fixed to the one side of the casing of the ink cartridge1and the ink is introduced through the opening103. As compared with the above-described conventional arrangement in which the valve member is placed in its open state and the ink is introduced via the valve member, the present method assures simplified operation of filling the ink cartridge with the ink and does not require any jig exclusive for the ink cartridge. Aspects of the present invention may be used with at least one of filling an ink cartridge for a first time or refilling the ink cartridge after its ink supply has been at least partially used.

It is to be understood that the invention is not limited to the details of the illustrated embodiment, but may be embodied with various changes and modifications, which may occur to those skilled in the art, without departing from the spirit and scope of the invention defined in the attached claims.