Protector for ink cartridge

A protector for use with an ink cartridge. The ink cartridge includes an ink chamber which stores an ink; an ink supply hole through which the ink is supplied from the ink chamber to an outside of the ink cartridge and which opens in a hole-open portion of an outer surface of the ink cartridge; and a valve member which is provided between the ink chamber and the ink supply hole, which selectively permits the ink to flow from the ink chamber to the ink supply hole and inhibits the ink from flowing from the ink chamber to the ink supply hole, and which communicates with the outside via the ink supply hole. The protector includes a main portion including an engaging portion which is adapted to engage a portion of the ink cartridge so that the protector is detachably attached to the ink cartridge. The main portion has a rigidity assuring that the main portion can substantially maintain an original shape thereof. The main portion further includes an access-restraining portion which is adapted to be located, in a state in which the protector is attached to the ink cartridge, outside the ink supply hole so as to at least partly cover the hole-open portion of the outer surface of the ink cartridge and thereby restrain an external access to the valve member via the ink supply hole.

The present application is based on Japanese Patent Application No. 2004-333922 filed on Nov. 18, 2004, the contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a protector that can prevent leakage of ink from an ink cartridge before the cartridge is attached to a recording device.

2. Discussion of Related Art

Japanese Patent Application Publication No. 2001-113723 or its corresponding U.S. Pat. No. 6,786,581B1 discloses an ink cartridge having an ink supply hole in which a valve member is provided. In a state of the ink cartridge before it is attached to an inkjet recording device, a compression spring elastically presses the valve member against a tubular packing member provided in the ink supply hole, so as to prevent leakage of ink from the ink supply hole. Meanwhile, when the ink cartridge is attached to the inkjet recording device, a tubular ink-supply needle pushes the valve member against the biasing force of the compression spring, so as to open the ink supply hole and thereby allow the ink to be supplied from the ink cartridge to the recording device.

However, the above-described valve member communicates with an outside space via the ink supply hole. Therefore, if the valve member is erroneously assembled in a tilted state when the ink cartridge is manufactured, or if the valve member is tilted by being interfered with by a foreign matter or a working person when the ink cartridge is manufactured or shipped, the ink may leak through the valve member tilted.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to solve at least one of the above-indicated problems. It is another object of the present invention to provide a protector that can protect a valve member of an ink cartridge and thereby prevent leakage of ink from the cartridge.

The above objects may be achieved according to the present invention. According to the present invention, there is provided a protector for use with an ink cartridge. The ink cartridge includes an ink chamber which stores an ink; an ink supply hole through which the ink is supplied from the ink chamber to an outside of the ink cartridge and which opens in a hole-open portion of an outer surface of the ink cartridge; and a valve member which is provided between the ink chamber and the ink supply hole, which selectively permits the ink to flow from the ink chamber to the ink supply hole and inhibits the ink from flowing from the ink chamber to the ink supply hole, and which communicates with the outside via the ink supply hole. The protector comprises a main portion including an engaging portion which is adapted to engage a portion of the ink cartridge so that the protector is detachably attached to the ink cartridge. The main portion has a rigidity assuring that the main portion can substantially maintain an original shape thereof. The main portion further includes an access-restraining portion which is adapted to be located, in a state in which the protector is attached to the ink cartridge, outside the ink supply hole so as to at least partly cover the hole-open portion of the outer surface of the ink cartridge and thereby restrain an external access to the valve member via the ink supply hole.

In the ink-cartridge protector in accordance with the present invention, the main portion thereof has a rigidity assuring that the main portion can substantially maintain its original shape, the engaging portion thereof is adapted to engage a portion of the ink cartridge, so that the protector is detachably attached to the ink cartridge, and the access-restraining portion thereof is adapted to be located outside the ink supply hole so as to at least partly cover the hole-open portion of the outer surface of the ink cartridge and thereby restrain external accesses to the valve member via the ink supply hole. Since an outside surface of the access-restraining portion is remoter from the valve member than the hole-open portion of the outer surface of the ink cartridge, the access-restraining portion can more effectively prevent the foreign accesses to the valve member than the hole-open portion. Therefore, when the ink cartridge is manufactured or is shipped, the protector can restrain a foreign matter or a person from interfering with the valve member. Thus, the valve member can be protected, and the leakage of the ink, caused by, e.g., tilting of the valve member resulting from the interference, can be prevented.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Hereinafter, there will be described preferred embodiments of the present invention by reference to the drawings. First, there will be described a general construction of an inkjet recording device2, by reference toFIGS. 1,2, and3. The inkjet recording device2is used with a plurality of ink cartridges1. Each of the ink cartridges1is protected by a protector70(FIG. 4) to which the present invention is applied, before it is used with the inkjet recording device2.

The inkjet recording device2includes a plurality of cartridge holders3each of which holds a corresponding one of the plurality of ink cartridges1, such that the corresponding ink cartridge1is attachable to, and detachable from, the each cartridge holder3. The inkjet recording device2is used with, e.g., four ink cartridges1that store four different color inks, respectively, for example, a cyan ink, a magenta ink, a yellow ink, and a black ink. In this case, the inkjet recording device2includes four cartridge holders3that hold the four ink cartridges1, respectively. Since the ink cartridges1have an identical construction and the cartridge holders3have an identical construction, the following description relates to only a representative one of the ink cartridges1and a representative one of the cartridge holders3.

The inkjet recording device2additionally includes an ink tank5that reserves an ink supplied from the ink cartridge1via an ink supply tube4; a recording head7that ejects droplets of the ink reserved by the ink tank5, toward a recording sheet6as a sort of recording medium; a carriage8that carries the ink tank5and the recording head7and is linearly reciprocated; two guide shafts9that cooperate with each other to guide the reciprocal movements of the carriage8; a sheet feeder10that feeds the recording sheet6; and a purging device11.

The cartridge holder3includes a base portion3a, and two guide portions3bthat project upward from two opposite sides of the base portion3a, respectively. The base portion3ahas an ink delivery tube12that projects upward into an inner space of the cartridge holder3and supplies the ink stored by the ink cartridge1, to the ink supply tube4; and an air supply hole13that supplies an ambient air into the ink cartridge1.

The ink supply tube4is connected, at one end thereof, to a lower end of the ink delivery tube12, and is communicated, at another end thereof, with the ink tank5. The air supply hole13is communicated with the ambient air, i.e., the atmosphere via a labyrinth-like air-flow passage, not shown.

As shown inFIG. 1, one of the two guide walls3bthat projects upward from one of lengthwise opposite ends of the base portion3a, more specifically described, that is located on the side of the ink delivery tube12, has, on an inner surface thereof, two first ribs3b1(FIG. 3) that extend, parallel to each other, in a direction in which the ink cartridge1is attached to, and detached from, the cartridge holder3, and are spaced from each other in a direction perpendicular to a lengthwise direction of the base portion3a. In addition, the base portion3ahas, on the side of the air supply hole13that is lengthwise opposite to the ink delivery tube12, two recessed portions3a1(FIG. 3) that are spaced from each other in the direction perpendicular to the lengthwise direction of the base portion3a.

The ink cartridge1has, on a side surface thereof that is opposed to the two first ribs3b1when the cartridge1is attached to the cartridge holder3, a second rib1c3that is to be inserted in a space present between the two first ribs3b1. In addition, the ink cartridge1has, on a lower surface thereof opposite to the above-indicated side surface thereof, two second projecting portions1c2(a first projecting portion1c1will be described later) that are to be inserted in the two recessed portions3a1, respectively. Since the second rib1c3is inserted in the space between the two first ribs3b1and the two second projecting portions1c2are inserted in the two recessed portions3a1, respectively, the ink cartridge1is accurately positioned in the cartridge holder3. The two second projecting portions1c2provide at least one protruding portion of the ink cartridge1.

As shown inFIG. 3, the cartridge holder3additionally includes a third guide wall3bwhich extends in the lengthwise direction of the base portion3aand from which an elastically deformable arm3b2projects upward. The arm3b2has, as an upper end portion thereof, an engaging portion3b3. When the ink cartridge1is attached to the cartridge holder3, the arm3b2is elastically deformed to allow the engaging portion3b3to engage an upper surface of the ink cartridge1. Thus, the ink cartridge1remains attached to the cartridge holder3.

The recording head7has a plurality of ink ejection nozzles, not shown, and a piezoelectric actuator, not shown, that is deformable to eject, from an arbitrary one of the nozzles, a droplet of the ink supplied from the ink tank5, toward the recording sheet6.

The purging device11is provided, at a location beyond a recording area in which the recording head7can record images on the recording sheet6, such that the purging device11can be opposed to the recording head7being positioned at that location. The purging device11includes a purging cap11athat covers a nozzle-defining surface of the recording head7that defines the nozzles; a purging tube11bthat communicates with the purging cap11a; and a suction pump11cthat sucks the ink from the nozzles via the purging tube11b.

As shown inFIG. 4, the ink cartridge1includes a main case1athat holds an ink and opens upward; a lid member1bthat covers an upper open end of the main case1a; and a cap member1cthat covers a lower end of the main case1a. The main case1a, the lid member1b, and the cap member1care each formed of a resin, and are integrally fixed to each other by supersonic welding, thermal welding, or adhesion.

The main case1ahas an ink chamber20that stores the ink; a bottom wall21that defines a bottom of the ink chamber20; and a side wall22that extends from an outer periphery of the bottom wall21, in an upward direction (FIG. 4), and cooperates with the bottom wall21to define the ink chamber20.

The bottom wall21has a supply chamber25that supplies the ink from the ink chamber20to the outside of the ink cartridge1; an air introducing chamber26that introduces the ambient air into the ink chamber20; and an ink charging chamber29through which the ink is charged into the ink chamber20. Each of the supply chamber25, the air introducing chamber26, and the ink charging chamber29is defined by a corresponding one of three tubular walls1dthat are integrally formed with the bottom wall21and project downward from a lower surface of the same21.

The cap member1chas an ink supply hole23, an air introducing hole24, and an ink charging hole37at respective positions where the ink supply hole23, the air introducing hole24, and the ink charging hole37are opposed to the supply chamber25, the air introducing chamber26, and the ink charging chamber29, respectively, and thereby allow the corresponding chambers25,26,29to communicate with the space outside the ink cartridge1. The cap member1chas the above-described second lib1c3on a side surface thereof that is located on the side of one of lengthwise opposite ends thereof, and additionally has the above-described two second projecting portions1c2on a lower surface thereof that is located on the side of the other lengthwise end thereof. More specifically described, the two second projecting portions1c2are provided on either side of the air introducing hole24. The cap member1cfurther has a tubular, first projecting portion1c1that projects downward from the lower surface thereof and defines, therein, the ink supply hole23. The first projecting portion1c1provides at least one protruding portion of the ink cartridge1. Each of the first projecting portion1c1and the two second projecting portions1c2projects, from the lower surface of the cap member1c, in a direction parallel to a direction in which an operable portion62of a second valve device28(a first valve device27will be described later) projects beyond the lower surface of the cap member1c, by an amount substantially equal to, or greater than, an amount of projection of the operable member62. Thus, the ink cartridge1can be stably placed on, e.g., a desk in such a manner that the cartridge1takes an upright posture in which the cartridge1rests on the three projecting portions1c1,1c2and, in this upright posture, the operable member62is not pushed upward, i.e., the second valve device28is not opened.

In the supply chamber25, there is provided the first valve device27that can shut off the communication between the inside, and the outside, of the ink cartridge1; and in the air introducing chamber26, there is provided the second valve device28that can also shut off the communication between the inside, and the outside, of the ink cartridge1. In addition, an elastic plug30is press-fitted in the ink charging chamber29. The elastic plug30can also shut off the communication between the inside, and the outside, of the ink cartridge1. The first and second valve devices27,28and the elastic plug30will be described below in more detail.

The bottom wall21of the main case1ahas, in a portion thereof located on the side of the supply chamber25, a plurality of communication holes31through which the ink chamber20and the supply chamber25communicate with each other. In the vicinity of the communication holes31, a through-hole32is formed in the bottom wall21, and an axis portion35of a check valve33is loosely fitted in the through-hole32such that the check valve33is movable upward and downward in the same32. The check valve33includes a large-diameter portion36as an intermediate portion of the axis portion35thereof, and an elastic membrane portion34provided in an axially end portion thereof.

The check valve33is supported by the bottom wall21such that under a normal condition, the elastic membrane portion34of the check valve33is kept, by the large-diameter portion36, remote from the communication holes31, so that the ink is allowed to flow from the ink chamber20to the supply chamber25. However, when flows of the ink from the ink delivery tube12(FIG. 1) toward the ink chamber20may occur, the elastic membrane portion34of the check valve33is moved upward to close the communicate holes31and thereby inhibit those flows.

In addition, the bottom wall21of the main case1ahas, in a portion thereof located on the side of the air introducing chamber26, a tubular, air introducing portion40that is integrally formed with the bottom wall21such that the air introducing portion40projects from the bottom wall21toward an upper portion of the ink chamber20. An upper end of the air introducing portion40opens at a position higher than a level of the ink present in the ink chamber20, and an inner flow passage41of the air introducing portion40communicates, at a lower end thereof, with the air introducing chamber26.

A portion of the bottom wall21that defines the ink charging chamber29has a communication hole45through which the ink chamber20and the ink charging chamber29communicate with each other.

Here, the first valve device27, provided in the supply chamber25, is described in detail.

The first valve device27includes a support member50that is formed of an elastic material such as a rubber; and a valve member51that is formed of a resin. The support member50has a generally cylindrical shape, and includes a valve-seat portion50athat is located in an intermediate portion thereof as seen in an axial direction thereof a biasing portion50bthat is located nearer to the ink chamber20than the valve-seat portion50a; and an attachment portion52that is located around the valve-seat portion50aand the biasing portion50b. The valve-seat portion50a, the biasing portion50b, and the attachment portion52are formed integrally with each other. The valve member51is accommodated by an inner space of the biasing portion50b, such that the valve member51is biased by the biasing portion50bin a direction to seat on the valve-seat portion50a.

The attachment portion52is sandwiched, and fixedly held, by a stepped surface1eformed in an inner circumferential surface of the supply chamber25, and the cap member1c.

The valve-seat portion50ahas, in a central portion thereof an opening54that opens toward the valve member51; an insertion hole55located under the opening54; and a tapered introduction hole56located under the insertion hole55. The opening54, the insertion hole55, and the introduction hole56cooperate with each other to define a through-hole that is formed through the valve-seat portion50ain the axial direction of the support member50. The insertion hole55has a size (e.g., an inner diameter) assuring that when the ink cartridge1is held by the cartridge holder3, the ink delivery tube12of the holder3can be liquid-tightly inserted in the insertion hole55.

The biasing portion50bhas a cylindrical side wall57that projects from the outer periphery of the valve-seat portion50ain an upward direction toward the ink chamber20; an annular portion58that projects in an inward direction from an upper end of the side wall57so as to contact a portion of the valve member51that is located on the side of the ink chamber20; and an opening58aformed in a central portion of the annular portion58.

The biasing portion50bbiases, owing to an elastic force of the side wall57and the annular portion58, the valve member51in a direction to cause the valve member51to seat on the valve-seat portion50a, so that under a normal condition, the valve member51is liquid-tightly seated on the valve-seat portion50a. Meanwhile, when the ink cartridge1is held by the cartridge holder3, as shown inFIG. 2, the ink delivery tube12is inserted in the insertion hole55so as to push the valve member51in an upward direction toward the ink chamber20. Thus, the side wall57is stretched out and the annular portion58is moved in the upward direction, so that a gap functioning as an ink-flow passage is produced between a lower portion of the valve member51and the valve-seat portion50a.

As shown inFIG. 2, the valve member51has a plurality of communication passages51athrough which the opening58aof the biasing portion50bcommunicates with a portion of the inner space of the biasing portion50bthat is located radially outward of a surface of the valve member51that can be liquid-tightly contacted with the valve-seat portion50a. When the valve member51is pushed upward as described above, the ink chamber20is communicated with an upper end of the ink delivery tube12via the communication passages51a, so that the ink is supplied to the ink delivery tube12via a plurality of notch-like communication ports12athat are formed in the upper end of the tube12.

Next, the second valve device28, provided in the air introducing chamber26, is described in detail.

Like the first valve device27, the second valve device27includes a support member60that is formed of an elastic material such as a rubber; and a valve member61that is formed of a resin. Like the support member50of the first valve device27, the support member60of the second valve device28includes a valve-seat portion60a; a biasing portion60b; and an attachment portion60cthat are formed integrally with each other. Since those portions60a,60b,60cof the support member60have respective functions that are identical with those of the corresponding portions50a,50b,52of the support member50, the description of those portions60a,60b,60cis omitted.

The support member60has a through-hole60dthrough which the operable portion62of the valve member61extends; and a cylindrical sealing portion60eintegrally projecting downward from a lower surface of the valve-seat portion60a, such that the sealing portion60esurrounds the through-hole60d.

The valve member61includes an upper, cylindrical portion63; the lower, operable portion62; and an intermediate, valve portion64.

The cylindrical portion63has a cylindrical shape projecting vertically upward from the valve portion64, and extends through a central opening of the biasing portion60bsuch that the cylindrical portion63is spaced from an inner circumferential surface of the biasing portion60b. In addition, when the ink cartridge1is normally held by the cartridge holder3and accordingly the valve member61is moved upward, the cylindrical portion63is kept spaced from an inner circumferential surface of the inner flow passage41of the air introducing portion40.

The operable portion62projects vertically downward from the valve portion64(FIG. 4), and extends through the through-hole60dof the valve-seat portion60asuch that the operable portion63is kept spaced from an inner circumferential surface of the through-hole60d.

The valve portion64is provided between the cylindrical portion63and the operable portion62, and has a disc-like shape. Under a normal condition, a lower surface of the valve portion64is contacted with the valve-seat portion60aso as to prevent flows of the ambient air through the second valve device28. As shown inFIG. 2, when the ink cartridge1is held by the cartridge holder3, the lower surface of the operable portion62is pushed upward by the base portion3a, so that the valve member61is moved upward and a gap functioning as an air-flow passage is produced between the valve portion64and the valve-seat portion60a. More specifically described, the sealing portion60eair-tightly contacts an upper surface of the base portion3asuch that the sealing portion60esurrounds the air supply hole13of the base portion3a. Thus, the ink chamber20and the air supply hole13air-tightly communicate with each other. Like the valve member51, the valve portion64has a plurality of communication passages64athat allow, when the valve member61is pushed up, the ink chamber20to communicate with the through-hole60d.

Next, the elastic plug30will be described in detail.

The elastic plug30, press-fitted in the ink charging chamber29, is formed of an elastic material such as a rubber, has a cylindrical shape, and is used in charging an ink into the ink chamber20. The ink is charged into the ink chamber20, in such a manner that first a protector70, described later, is attached to the ink cartridge1that has already been assembled, and then air is discharged from the ink chamber20so as to decrease a pressure of the air in the same20. The air pressure in the ink chamber20may be decreased by connecting a vacuum pump, not shown, to the insertion hole55or the through-hole60d, pushing the valve member51or the valve member61upward, and operating the vacuum pump to discharge the air from the ink chamber20. Alternatively, as shown inFIG. 4, the sealing plug30may be penetrated by a tubular needle80so that a vacuum pump can discharge air from the ink chamber20via the ink charging chamber29and the needle80. Subsequently, another tubular needle, not shown, for charging ink is operated to penetrate the sealing plug30in the same manner as described above, so that an ink supply source, not shown, can charge ink into the ink chamber20via the needle and the ink charging chamber29.

Though a through-hole is temporarily formed by the needle80penetrating the sealing plug30, the through-hole is naturally closed by an elastic restoring deformation of the sealing plug30, when the needle80is pulled out of the same30. In addition, after the ink is charged into the ink chamber20, the elastic plug30is pressed into the ink charging chamber29, to a position where an upper surface of the plug30contacts a lower surface of the bottom wall21. Thus, the communication passage45between the ink chamber20and the ink charging chamber29is shut off by the sealing plug30, and an amount of ink remaining in the ink charging chamber29is pushed out into the ink chamber20.

Next, the protector70will be described in detail.

As shown inFIGS. 5A and 5B, the protector70has a main portion including a bottom wall71having a plan-view shape similar to that of the lower surface of the cap member1cof the cartridge1, i.e., the lower end surface of the cartridge1, and additionally including a side wall75that projects upward from an outer periphery of the bottom wall71. The protector70additionally has a lug76as an operable portion that is integral with one end portion of the main portion71,75. The bottom wall71, the side wall75, and the lug76are formed of a resin such that those elements71,75,76are integral with each other. The main portion71,75has a rigidity assuring that the main portion71,75can maintain its original shape.

Since the protector70has a color different from a color of each of the valve members51,61, a person such as a worker or a user can easily distinguish the protector70from the each valve member51,61. Thus, when the working person views the valve members51,61with the naked eyes, the person can easily identify each one of the protector70and the valve members51,61, which leads to improving an operation efficiency as will be described later.

As shown inFIG. 5A, the bottom wall71has a flat shape whose one end (i.e., a left-hand end as seen in the figure) is substantially arcuate, and has a first view hole72, a second view hole73, and a third hole74that are formed through a thickness of the bottom wall71, at respective positions corresponding to the ink supply hole23, the air introducing hole24, and the ink charging hole37of the ink cartridge1, respectively. The protector70additionally includes a pair of fitting walls77each of which has an arcuate shape in its plan view and which cooperate with each other to surround the first view hole72; and a cylindrical wall78that surrounds the third hole74. The two fitting walls77and the cylindrical wall78integrally project upward from the bottom wall71. Since the pair of fitting walls77are integral with the bottom wall71formed of resin, those fitting walls77are elastically deformable to some degree.

An outer diameter of the pair of arcuate fitting walls77is somewhat larger than an inner diameter of the cylindrical first projecting portion1c1of the cap member1c. Since the fitting walls77are strongly press-fitted in the first projecting portion1c1, owing to an elastic deformation of the resin as the material of the fitting walls77, the protector70is strongly engaged with, and held by, the ink cartridge1, owing to a frictional force produced between respective outer surfaces of the arcuate fitting walls77and an inner circumferential surface of the first projecting portion1c1. This state is shown inFIG. 4. In this state, the lug76projects laterally from a portion of the side wall75that is located on the side of the ink supply hole23of the ink cartridge1. In this state, if a person pushes the lug76in a downward direction, the fitting walls77are elastically deformed and are disengaged from the first projecting portion1c1, so that the protector70can be detached from the ink cartridge1.

However, in a modified embodiment of the present invention, an inner diameter of the pair of arcuate fitting walls77of the protector70may be somewhat smaller than an outer diameter of the cylindrical first projecting portion1c1of the cap member1c. In this case, the fitting walls77can be strongly press-fitted on the first projecting portion1c1, such that the protector70is strongly engaged with, and held by, the ink cartridge1, owing to a frictional force produced between respective inner surfaces of the fitting walls77and an outer circumferential surface of the first projecting portion1c1.

After the main case1a, the lid member1b, the cap member1c, the two valve devices27,28, the elastic plug30, and the check valve33are assembled into the ink cartridge1, and before the ink is charged into the ink chamber20, the protector70is applied or attached to the ink cartridge1in the above-described manner. Thereafter, the protector70remains attached to the ink cartridge1, e.g., in a state in which the ink cartridge1is packaged as shown inFIG. 6, before the ink cartridge1is attached by a user to the cartridge holder3of the inkjet recording device2.

In the state in which the protector70is attached to the ink cartridge1, the bottom wall71extends parallel to the lower surface of the cap member1cover the ink supply hole23and the air introducing hole24, and the arcuate end portion of the bottom wall71is located inward of the two second projecting portions1c2of the cap member1c. The protector70additionally includes two ribs79that project, while extending parallel to each other along the lug76, upward from an opposite end portion of the bottom wall71that is opposite to the arcuate end portion thereof. The second rib1c3of the cap member1ccan be inserted in a space present between the two ribs79of the protector70.

The third hole74of the protector70can be used as a route through which the needle80is inserted to penetrate the elastic lug30and inject the ink into the ink chamber20.

A height dimension of the main portion71,75of the protector70, i.e., the bottom wall71and the side wall75, as measured in a direction in which the operable portion62of the second valve device28projects downward from the lower surface of the cap member1c, is substantially equal to, or greater than, an amount of downward projection of the operable portion62from the lower surface of the cap member1cin the state in which the valve portion64of the valve member61is seated on the valve-seat portion60a, and is substantially equal to, or greater than, an amount of downward projection of the two second projecting portions1c2from the lower surface of the cap member1c. Therefore, in the state in which the protector70is attached to the ink cartridge1as above described and an upper end of the side wall75is held in contact with the lower surface of the cap member1c, the operable portion62does not project downward beyond a lower surface of the protector70, as shown inFIG. 4. Thus, the protector70can fully cover the operable portion62.

In addition, the valve member51of the first valve device27is provided at a position sufficiently remote from the lower surface of the protector70. Therefore, when the protector70is attached to the ink cartridge1and/or when the ink cartridge1with the protector70is shipped, a possibility that the valve member51or the operable portion62may be interfered with by a foreign matter or a working person and the ink may leak through the valve devices27,28can be minimized.

A height dimension of the side wall75as measured from the bottom wall71is substantially equal to, or greater than, an amount of downward projection of the sealing portion60eof the second valve device28from the lower surface of the cap member1c. Therefore, in the state in which the protector70is attached to the ink cartridge1, the sealing portion60ecan be effectively prevented from being permanently deformed by the bottom wall71.

The first or second view hole72,73of the protector70is not essentially needed for the purpose of restraining a foreign matter from interfering with the valve member51or the valve portion64of the ink cartridge1. Thus, the protector70may be formed of a transparent material such as a transparent resin. However, in the present embodiment, the first and second view holes72,73are provided for the purpose of inspecting whether each of the valve member51and the valve portion64has erroneously been assembled in a tilted state, whether each of the valve member51and the valve portion64has been tilted because of interference of a foreign matter or a working person before the protector70is attached to the ink cartridge1, and/or whether ink is leaking from the first or second valve device27,28because of other reasons.

Thus, a transverse cross-section area of each of the first and second view holes72,73is determined at a value assuring that a person can view, through the each view hole72,73from an outer side of the protector70that is opposite to the ink cartridge1, a contour of a corresponding one of the insertion hole55and the through-hole60dand at least a portion of a corresponding one of the valve member51and the valve portion64each of which is provided on an inner side of a corresponding one of the insertion hole55and the through-hole60d. Preferably, the transverse cross-section area of each of the first and second view holes72,73is determined to be larger than a transverse cross-section area of a corresponding one of the insertion hole55and the through-hole60d.

In the state in which the protector70is attached to the ink cartridge1, a center of the first view hole72is located substantially on a straight extension line extended from a straight passing line passing through a center of the ink supply hole23and the valve member51; and a center of the second view hole73is located substantially on a straight extension line extended from a straight passing line passing through a center of the air introducing hole24and the valve portion64. Thus, the transverse cross-section area of each of the first and second view holes72,73can be minimized while assuring that a person can inspect, therethrough, a posture of a corresponding one of the valve member51and the valve portion64and a leakage of the ink from a corresponding one of the first and second valve devices27,28. Thus, the transverse cross-section area of each of the first and second view holes72,73is smaller than a transverse cross-section area of a corresponding one of the ink supply hole23and the air introducing hole24. However, the transverse cross-section area of the second view hole73is larger than a transverse cross-section area of the operable portion62of the valve member61. Thus, each of the first and second view holes72,73allows a person to inspect a posture of a corresponding one of the valve member51and the valve portion64and a leakage of the ink from a corresponding one of the first and second valve devices27,28, while restraining a foreign matter from interfering with each of the valve member51and the valve portion64or causing a leakage of the ink from each of the first and second valve devices27,28.

As shown inFIG. 6, when the ink cartridge1with the protector70is shipped, the ink cartridge1is packaged in an air-impermeable bag90formed of a resin. Then, air is sucked from the bag90to reduce an air pressure in the bag90and thereby provide a vacuum package of the ink cartridge1. In this state, the bag90is closely contacted with the outer surface of the ink cartridge1. Since, however, the ink cartridge1is protected by the protector70, the operable portion62can be prevented from being pushed by the bag90and accordingly the ink can be prevented from leaking from the ink cartridge1.

The bag90is formed of a transparent or translucent material assuring that a person can view, therethrough, the posture of each of the valve member51and the valve portion64and/or the leakage of ink from each of the valve devices27,28. Thus, even after the ink cartridge1is packaged in the bag90, a working person can perform the valve inspecting operation.

While the present invention has been described in its preferred embodiment, the present invention may be embodied in different manners.

For example, in the above-described embodiment, each of the first and second view holes72,73has a substantially circular transverse cross-section shape. However, each of the first and second view holes72,73may have a different shape, such as a polygonal shape or an elliptic shape, so long as the each view hole72,73assures that a person can inspect, therethrough, a corresponding one of the valve devices27,28.

In addition, in the above-described embodiment, the second valve device28employs the valve member61as shown inFIG. 4. However, the second valve device28may be replaced with a different valve device identical with the first valve device27employing the valve member51. Likewise, the first valve device27may be replaced with a different valve device identical with the second valve device28employing the valve member61.

In the above-described embodiment, the bottom wall71that cooperates with the side wall75to constitute an access-restraining portion has the first view hole72that is formed through the thickness thereof and that has a position and a size that assure that a person can view, therethrough, at least a portion of the first valve member51via the ink supply hole23. Therefore, in the state in which the protector70is attached to the ink cartridge1, a person can view, through the first view hole72of the protector70, the first valve member51via the ink supply hole23. Thus, even if the first valve member51may be tilted because of, e.g., an assembling error, the person can easily recognize the tiling of the valve51, i.e., can early detect a defective ink cartridge1that might cause a leakage of the ink, or can early detect the leakage of the ink from the cartridge1.

In the above-described embodiment, the center of the first view hole72is positioned substantially on a straight extension line extended from a straight passing line passing through the center of the first valve member51and the center of the ink supply hole23. Therefore, through the first view hole72the cross-section area of which is minimized, the person can view the first valve member51via the ink supply hole23. Since the cross-section area of the first view hole72can be minimized, the access-restraining portion71,75can shield the first valve member51to a maximum degree and thereby effectively protect the same51.

In the above-described embodiment, the cross-section area of the first view hole72is smaller than that of the ink supply hole23. Therefore, when the ink cartridge1is manufactured, the protector70can prevent a worker from erroneously contacting the first valve member51; and when a user attaches the ink cartridge1to the recording device2, the protector70can effectively prevent the user from erroneously contacting the first valve member51. Thus, the protector70can reliably protect the first valve member51from the time when the ink cartridge1is manufactured to the time when the cartridge1is attached to the recording device2.

In the above-described embodiment, the ink cartridge1additionally includes the air introducing hole24which introduces the ambient air from the outside of the ink cartridge1into the ink chamber20, and the second valve member61which is provided between the ink chamber20and the air introducing hole24, and the bottom wall71covers the outer surface of the ink cartridge1over the ink supply hole23and the air introducing hole24and thereby prevent external accesses to each of the first and second valve members51,61via a corresponding one of the ink supply hole23and the air introducing hole24. Therefore, the protector70can prevent foreign matters (e.g., a person) from interfering with each of the first and second valve members51,61. Thus, the first and second valve members51,61can be protected, and the leakage of the ink, caused by, e.g., tilting of the first or second valve member51,61resulting from the interference, can be prevented.

In the above-described embodiment, the ink supply hole23and the air introducing hole24open in one end surface of the ink cartridge1, and the bottom wall71covers the end surface of the ink cartridge1over the ink supply hole23and the air introducing hole24. Therefore, in the state in which the protector70is attached to the ink cartridge1, the first and second valve members51,61can be protected, and can be viewed or inspected through the ink supply hole23and the air introducing hole24, respectively. Thus, the bottom wall71can have a simplified shape, such as a substantially linear shape, which leads to reducing the production cost of the protector70.

In the above-described embodiment, the bottom wall71has the second view hole73which is formed through the thickness thereof and which has a position and a size which assure that a person can view, therethrough, at least a portion of the second valve member61via the air introducing hole24. Therefore, in the state in which the protector70is attached to the ink cartridge1, a person can view, through the second view hole73of the protector70, the second valve member61via the air introducing hole24. Thus, the person can easily recognize, e.g., the tiling of the second valve member61, and can stop shipping the defective ink cartridge1.

In the above-described embodiment, the center of the second view hole73is positioned substantially on a straight extension line extended from a straight passing line passing through the center of the second valve member61and the center of the air introducing hole24. Therefore, through the second view hole73the cross-section area of which is minimized, the person can view the second valve member61via the air introducing hole24. Since the cross-section area of the second view hole73can be minimized, the bottom wall71can shield the second valve member61to a maximum degree and thereby effectively protect the same61.

In the above-described embodiment, the cross-section area of the second view hole73is smaller than that of the air introducing hole24. Therefore, when the ink cartridge1is produced, the protector70can prevent a worker from erroneously contacting the second valve member61; and when a user attaches the ink cartridge1to the recording device2, the protector70can prevent the user from erroneously contacting the second valve member61. Thus, the protector70can reliably protect the second valve member61from the time when the ink cartridge1is produced to the time when the cartridge1is attached to the recording device2.

In the above-described embodiment, the second valve member61includes the operable portion62which extends through the air introducing hole24and projects from the outer surface of the ink cartridge1into the outside of the ink cartridge1so that the operable portion62is externally operable to operate the second valve member61, and the dimension of the access-restraining portion, i.e., the bottom wall71and the side wall75, that is measured in the direction in which the operable portion62projects from the outer surface of the ink cartridge1into the outside, is substantially equal to, or greater than, the amount of projection of the operable portion62from the outer surface of the ink cartridge1into the outside. Therefore, in the state in which the protector70is attached to the ink cartridge1, the access-restraining portion71,75can cover the outer surface of the ink cartridge1such that the operable portion62of the second valve member61does not project beyond the access-restraining portion71,75. Therefore, when the ink cartridge1is produced or shipped, the protector70can prevent foreign matters from erroneously contacting the operable portion62and thereby reliably protect the second valve member61.

In the above-described embodiment, the ink cartridge1additionally includes the first and second projecting portions1c1,1c2as the at least one protruding portion that project or protrude from the outer surface thereof in an outward direction parallel to the direction of projection of the operable portion62of the second valve member61, and the dimension of the access-restraining portion71,75is substantially equal to, or greater than, the amount of protrusion of the at least one protruding portion1c2from the outer surface of the ink cartridge1. Therefore, in the state in which the protector71is attached to the ink cartridge1, the access-restraining portion71,75covers the outer surface of the ink cartridge such that the at least one protruding portion1c1,1c2does not protrude beyond the access-restraining portion71,75. In addition, since the amount of protrusion of the at least one protruding portion1c1,1c2from the outer surface of the ink cartridge1is substantially equal to, or greater than, the amount of projection of the operable portion62of the second valve member61from the outer surface of the ink cartridge1. Therefore, even in a state in which the protector71is not attached to the ink cartridge1, the at least one protruding portion1c1,1c2can restrain foreign matters from interfering with the operable portion62of the second valve member61and thereby protect the second valve member61.

In the above-described embodiment, the access-restraining portion71,75has a color different from a color of at least one of the first and second valve members51,61. Therefore, a person can easily distinguish the access-restraining portion71,75from the first and/or second valve members51,61. Thus, a worker can easily identify the first and/or second valve members51,61, which leads to improving the operation efficiency of the worker.

It is to be understood that the present invention may be embodied with other changes and improvements that may occur to a person skilled in the art, without departing from the spirit and scope of the invention defined in the appended claims.