# Patent

## Title
Ink cartridges

## Abstract

An ink cartridge includes a first case having a wall having a first end and a second end opposite the first end. The wall has a first opening and a second opening formed therethrough, the first opening has a first center, and the second opening has a second center. The wall also has a first center line and a second center line which is perpendicular to the first center line, and each of the first center and the second center is offset from each of the first center line and the second center line. The ink cartridge also includes a second case enclosed within the first case, and an ink supply portion positioned adjacent to the second end of the wall, in which a portion of the ink supply portion is configured to be received by the first opening. The ink cartridge also includes an opaque, protruding portion extending from the second case and positioned at the wall between the first end of the wall and the ink supply portion, and a portion of the protruding portion is aligned with the second opening.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is a divisional of U.S. patent application Ser. No. 11/536,652, which was filed on Sep. 29, 2006 now U.S. Pat. No. 7,222,950, and claims priority from Japanese Patent Application No. JP-2005-284646, which was filed on Sep. 29, 2005, Japanese Patent Application No. JP-2005-342697, which was filed on Nov. 28, 2005, Japanese Patent Application No. JP-2005-377987, which was filed on Dec. 28, 2005, Japanese Patent Application No. JP-2006-064973, which was filed on Mar. 9, 2006, Japanese Patent Application No. JP-2006-081806, which was filed on Mar. 23, 2006, U.S. Provisional Patent Application No. 60/826,254, which was filed on Sep. 20, 2006, and U.S. patent application Ser. No. 11/536,652, the disclosures of which are incorporated by reference in their entirety.


BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to ink cartridges. In particular, the present invention is directed towards ink cartridges which may be used in combination with ink jet printers.
2. Description of Related Art
Ink cartridges which are configured to be used in combination with ink jet printers are known in the art.
SUMMARY OF THE INVENTION
According to an embodiment of the present invention, an ink cartridge comprises a first case comprising a wall having a first end and a second end opposite the first end. The wall has a first opening and a second opening formed therethrough, the first opening has a first center, and the second opening has a second center. The wall also has a first center line and a second center line which is perpendicular to the first center line, and each of the first center and the second center is offset from each of the first center line and the second center line. The ink cartridge also comprises a second case enclosed within the first case, and an ink supply portion positioned adjacent to the second end of the wall, in which at least a portion of the ink supply portion is configured to be received by the first opening. Moreover, the ink cartridge comprises an opaque, protruding portion extending from the second case and positioned at the wall between the first end of the wall and the ink supply portion, and at least a portion of the protruding portion is aligned with the second opening.
According to another embodiment of the present invention, an ink cartridge comprises a wall having a first end and a second end opposite the first end. The wall has a first center line and a second center line which is perpendicular to the first center line. The ink cartridge also comprises an ink supply portion positioned adjacent to the second end of the wall, and the ink supply portion has a first center which is offset from each of the first center line and the second center line. Moreover, the ink cartridge comprises a translucent portion positioned at the wall between the first end of the wall and the ink supply portion, and the translucent portion has a second center which is offset from each of the first center line and the second center line.



BRIEF DESCRIPTION OF THE DRAWINGS 
For a more complete understanding of the present invention, the needs satisfied thereby, and the features and technical advantages thereof, reference now is made to the following descriptions taken in connection with the accompanying drawings.
FIG. 1 is a perspective view of an ink cartridge, according to an embodiment of the present invention.
FIG. 2 is an expanded, perspective view showing an interior of the ink cartridge of FIG. 1, according to an embodiment of the present invention.
FIG. 3(a) is a side view of a signal blocking portion of a movable member, which is disposed within an inner space of a translucent portion; FIG. 3(b) is a cross-sectional view of the signal blocking portion and the translucent portion of FIG. 3(a) along the XVIIIb-XVIIIb line; and FIG. 3(c) is a cross-sectional view of the signal blocking portion and the translucent portion of FIG. 3(a) along the XVIIIc-XVIIIc line, according to an embodiment of the present invention.
FIG. 4(a) is a front view of a movable member having a float member and a signal blocking portion; and FIG. 4(b) is a view of the movable member of FIG. 4(a) along the arrow XIXb perspective, according to an embodiment of the present invention.
FIG. 5(a) is a side view of an ink reservoir element; FIG. 5(b) is a side view of the front of the ink reservoir element of FIG. 5(a); and FIG. 5(c) is a cross-sectional view of the ink reservoir element of FIG. 5(a) along the XXc-XXc line, according to an embodiment of the present invention.
FIG. 6 is a cross-sectional view of a communication path of an ink cartridge, in which the ink cartridge is connected to a printer, according to an embodiment of the present invention.
FIG. 7 is a perspective view of an ink cartridge showing a process for attaching a protective cap to the ink cartridge, according to an embodiment of the present invention.
FIG. 8(a) is a side view of an ink reservoir element showing the position of a movable member when there is ink within the ink reservoir element; and FIG. 8(b) is a side view of the ink reservoir element of FIG. 8(a) showing the position of the movable member when there is no ink within the ink reservoir element, according to an embodiment of the present invention.
FIG. 9(a) is a perspective view of an ink cartridge according to another embodiment of the present invention; and FIG. 9(b) is a perspective view of an ink cartridge according to yet another embodiment of the present invention
FIG. 10 is a side view of an ink reservoir element, according to another embodiment of the present invention.
FIGS. 11(a)-11(d) are front views of different combinations case members connected to each other, according to an embodiment of the present invention.



DETAILED DESCRIPTION OF EMBODIMENTS
Embodiments of the present invention and their features and technical advantages may be understood by referring to FIGS. 1-11, like numerals being used for like corresponding portions in the various drawings.
Referring to FIGS. 1, 2, and 7, an ink cartridge 14 may comprise an ink reservoir element 100 which is configured to store ink, a case 200 which may substantially cover the entire body of ink reservoir element 100, and a protector 300 which may be attached to case 200 and protects ink reservoir element 100 when ink cartridge 14 is in transit. Case 200 may have a substantially rectangular, parallelepiped shape. In an embodiment of the present invention, ink reservoir element 100, case 200, protector 300, and all of the members contained in ink cartridge 14 may comprise non-metal materials, e.g., may comprise resin materials, such that they may be burned at the time of disposal. For example, nylon, polyester, or polypropylene may be used as resin materials.
Ink reservoir element 100 may comprise a frame portion 110 which forms an ink chamber 111 which is configured to store ink, an ink supply portion 120 which is configured to supply ink stored in ink chamber 111 to a multifunction device (not shown), such as a printer, and an ambient air intake portion 130 which is configured to introduce ambient air into frame portion 110. Ink reservoir element 100 also may comprise a translucent portion 140 which may allow for the detection of the amount of ink stored in ink chamber 111.
Case 200 may comprise a first case member 210 and a second case member 220 which are configured to sandwich ink reservoir element 100. First case member 210 may be a member which covers the bottom side surface of ink reservoir element 100, and second case element 220 may be a member which covers the top side surface of ink reservoir element 100. First and second case members 210 and 220 may comprise at least one resin material, and may be manufactured using injection molding.
A pair of case cutout portions 211 and 212 may be provided through first case member 210 for exposing ink supply portion 120 and ambient air intake portion 130, respectively, to the outside of case 200. Case cutout portions 211 and 212 may be substantially semicircular. A case cutout portion 213 also may be provided through first case member 210 between case cutout portion 211 and case cutout portion 212, and case cutout portion 213 may be for receiving a sensor (not shown) of the multifunction device at a position where the sensor sandwiches translucent portion 140. For example, case cutout portion 213 may have a substantially square or rectangular shape. Similarly, second case member 220 may comprise case cutout portions 221, 222, 223, which may correspond to case cutout portions 211, 212, and 213, respectively. When first case member 210 is connected to second case member 220 to form case 200, case cutout portions 211 and 221 may form a first opening, case cutout portions 212 and 222 may form a second opening, and case cutout portions 213 and 223 may form a third opening. Moreover, when ink reservoir element 100 is positioned within case 200, ink supply portion 120 may protrude from the first opening, ambient air intake portion 130 may protrude from the second opening, and a portion of translucent portion 140 may be aligned with the third opening.
Referring to FIGS. 11(a)-11(d), first case member 210 and second case member 220 may have various different shapes and sizes. For example, in FIG. 11(a), first case member 210 and second case member 220 have substantially the same shape and size, and are relatively small. In FIG. 11(b), first case member 210 and second case member 220 have substantially the same shape and size, and are relatively large. In each of FIGS. 11(a) and 11(b), when first case member 210 is connected to second case member 220 to form case 200, a vertical or first center line CL of case 200 may intersect a center of the first opening, the second opening, and the third opening. In FIG. 11(c), first case member 210 is larger, e.g., wider, than second case member 220, and in FIG. 11(d), second case member 220 is larger, e.g., wider, than first case member 210. In FIGS. 11(c) and 11(d), because the size of first case member 210 is different than the size of second case member 220, when first case member 210 is connected to second case member 220 to form case 200, center line CL of case 200 is offset from the center of the first opening, the second opening, and the third opening. Similarly, when ink reservoir element 100 is positioned within case 200, center line CL of case 200 also may be offset from a center of ink supply portion 120, a center of ambient air intake portion 130, and a center of translucent portion 140. Further, in FIGS. 11(a) through 11(d), when first case member 210 is connected to second case member 220 to form case 200, a horizontal or second center line CL2 of case 200 also may be offset from the center of the first opening, the second opening, and the third opening. Center line CL2 is perpendicular to the center line CL. Similarly, when ink reservoir element 100 is positioned within case 200, center line CL2 of case 200 also may be offset from a center of ink supply portion 120, a center of ambient air intake portion 130, and a center of translucent portion 140. Because center line CL2 is offset from the center of the third opening, when ink cartridge 14 is installed in the multifunction device up side down, the sensor cannot enter the third opening.
Referring to FIG. 2, in an embodiment of the present invention, each of first case member 210 and second case member 220 further may comprise a protrusion portion 506 extending from an end of the case member, which is adjacent to the first opening associated with ink supply portion 120. When first case member 210 and connected to second case member 220 to form case 200, the protrusion portion 506 of first case member 210 contacts the protrusion portion 506 of second case member 220 to form a single protrusion portion 506. The single protrusion portion 506 may have a center at the intersection of first case member 210 and second case member 220. Consequently, when ink cartridge 14 comprises the case 200 depicted in FIGS. 11(a) or 11(b), the center of the single protrusion 506 may be aligned with center line CL, and when ink cartridge 14 comprises the case 200 depicted in FIGS. 11(c) or 11(d), the center of the single protrusion 506 may be offset from center line CL and may be offset from center line CL2.
Referring to FIG. 3(a), translucent portion 140 may protrude outward from frame portion 110. Translucent portion 140 may comprise an enclosure portion 141 which encloses the end of a movable member 470, e.g., a signal blocking portion 473c of movable member 470, by sandwiching the end of movable member 470 with a pair of wall surfaces and forms a passage through which movable member 470 may be displaced. Translucent portion 140 also may comprise a translucent arm supporting portion 142 which may supports movable member 470 from below. Translucent arm supporting portion 142 may be positioned in the center of the width direction of the passage within translucent portion 140, and it may be arranged, such that the end of movable member 470 also is positioned in the center of the passage within translucent portion 140.
Movable member 470 may rotate based on the amount of ink within ink chamber 111, and it may be a member which may be used in combination with the sensor to detect whether the amount of ink within ink chamber 111 is sufficient by detecting the position of signal blocking portion 473c. The sensor may comprise a light emitting portion and a light receiving portion, and translucent portion 140 may be positioned therebetween. Therefore, when signal blocking portion 473c is positioned in the light path between the light emitting portion and the light receiving portion, it blocks the light transmitted by the light emitting portion. Consequently, by rotating based on the amount of ink within ink chamber 111, movable member 470 may change the amount of light received by the light receiving portion and may be used to detect the presence or absence of ink.
Referring to FIG. 3(b), the thickness of translucent arm supporting portion 142 may be selected, such that a gap t4 between the inside walls of enclosure portion 141 and the outside wall of translucent arm supporting portion 142 may be less than a gap t3 between the inside walls of enclosure 141 and the outside of movable member 470. When liquid surface I of the ink falls below translucent portion 140, the ink within translucent portion 140 may be depleted, however, because gap t3 between movable member 470 and enclosure 141 may be relatively small, ink may remain within translucent portion 140 due to the surface tension of the ink, and movable member 470 may not rotate normally due to the surface tension of the ink. Nevertheless, by forming arm supporting portion 142, such that gap t3 is greater than gap t4, the capillary force generated between translucent arm supporting portion 142 and enclosure portion 141 may be greater than the capillary force generated between movable member 470 and enclosure portion 141. Consequently, the ink which remains within enclosure portion 141 may be drawn between arm supporting portion 142 and enclosure portion 141, such that it may be possible to substantially prevent ink from remaining between movable member 470 and enclosure portion 141. As such, the amount of ink may be accurately detected.
Referring to FIGS. 4(a) and 4(b), movable member 470 may be a member for detecting the amount of ink within ink chamber 111. Movable member 470 may be manufactured by injection molding using a resin material, e.g., polypropylene, and it has light-blocking properties, e.g., it may be opaque. Movable member 470 may be a rotating member which rotates based on the amount of ink within ink chamber 111, and a portion of movable member 470 may be detected by the sensor which detects the amount of ink stored within ink chamber 111. Movable member 470 may comprise a float portion 471 which may comprise a material with a specific gravity which is less than the specific gravity of ink, a pivot portion 472 which may be attached to frame portion 110, such that it may pivot, and an arm portion 473, which extends from pivot portion 472 in a direction which may be substantially orthogonal to float portion 471. Pivot portion 472 may be a linking portion which connects float portion 471 and arm portion 473. In operation, when movable member 470 rotates upward, movable member 470 contacts a ceiling surface of translucent portion 140, and the rotation of movable member 470 may be restricted. Therefore, it may be possible to prevent movable member 470 from moving out of translucent portion 140.
Arm portion 473 may comprise a vertical arm portion 473a which extends in a direction which is substantially perpendicular to float portion 471, a sloping arm portion 473b which slopes upward from vertical arm portion 473a, and a signal blocking portion 473c, which may be used as a light-blocking portion which blocks the light transmitted by the light emitting portion of the sensor.
Referring to FIG. 4(b), arm portion 473 may be substantially thinner than float portion 471 and pivot portion 472. Specifically, if arm portion 473 has a thick profile, the scale of translucent portion 140 may be increased, and consequently, the size of ink cartridge 14 and the resistance when movable member 470 rotates also may increase, which makes it difficult to accurately detect the amount of ink. Further, when the thickness of translucent portion 140 increases, the gap between the light emitting portion and the light receiving portion of the sensor widens accordingly, and the detection sensitivity deteriorates, which increases the costs associated with the sensor. Therefore, arm portion 473 may have a relatively thin profile. A plurality of ribs 473d may be provided on vertical arm portion 473a and sloping arm portion 473b, which may increase the strength of arm portion 473.
A pair of substantially semispherical arm protruding portions 473e1 and 473e2 may be provided on signal blocking portion 473c on the top and the bottom of the portion housed within translucent portion 140, respectively. Arm protruding portions 473e1 and 473e2 may reduce the likelihood of signal blocking portion 473c adhering to the inside wall of translucent portion 140 due to the surface tension of the ink. For example, because arm protruding portions 473e1 and 473e2 may have a substantially semispherical shape, the only portion which contacts the inside wall of translucent portion 140 may be the end of arm protruding portions 473e1 and 473e2, such that the effects of the surface tension of the ink may be reduced.
Float portion 471 may comprise a resin material with a specific gravity which is less than the specific gravity of ink, such that when liquid surface I of the ink is lowered, float portion 471 moves in the direction of the bottom portion of frame portion 110, i.e., float portion 471 and liquid surface I of the ink move in the same direction as ink is dispensed. When float portion 471 moves in the direction of the bottom portion, and arm portion 473 moves in the direction of the top portion using pivot portion 472 as a rotational axis, signal blocking portion 473c may move out of between the light emitting portion and the light receiving portion and therefore, the state in which ink is depleted may be detected. Moreover, when the specific gravity of the materials comprising float portion 471 are less than the specific gravity of ink, it may be unnecessary to manufacture complex dies, such that the manufacturing cost of movable member 470 may be reduced.
Referring to FIGS. 5(a), and 5(b), ink supply portion 120, ambient air intake portion 130, and translucent portion 140 may be provided on one of the side surfaces of frame portion 110. When ink cartridge 14 is installed within the multifunction device, ambient air intake portion 130, translucent portion 140, and ink supply portion 120 may be sequentially aligned from top to bottom.
Referring to FIG. 5(a), a width t5 of translucent portion 140 may be less than a diameter t6 of the opening of ink supply portion 120, and a length t7 of translucent portion 140 may be greater than width t5 of translucent portion 140. Referring to FIG. 5(b), translucent portion 140 may be concave in the direction of frame portion with respect to ink supply portion 120 and ambient air intake portion 130. A width t8 of translucent portion 140 may be greater than width t5 of translucent portion 140.
Arm portion 473 of movable member 470 may be positioned within the inner space of translucent portion 140, and the light path of the sensor may be opened from the light-blocking state due to the rotation of arm portion 473, and the amount of ink may be detected. The light receiving portion and the light emitting portion may be positioned on both sides of translucent portion 140, such that both side surfaces of translucent portion 140 form detection surfaces 140a and 140b. Referring again to FIG. 5(a), detection surfaces 140a and 140b may be parallel to the height direction, e.g., Y-direction, of ink cartridge 14 when ink cartridge 14 is installed in the multifunction device.
When ink adheres to detection surfaces 140a and 140b, it may be difficult to accurately detect the amount of ink. Referring to FIG. 5(b), translucent portion 140 may be provided in a position withdrawn to the side of ink chamber 111 with respect to ink supply portion 120, such that it may be difficult for ink to adhere to translucent portion 140 even when ink drips from ink supply portion 120. Specifically, the ink which drops from ink supply portion 120 generally may not head towards translucent portion 140, such that it does not adhere to translucent portion 140.
Because detection surfaces 140a and 140b are vertical when ink cartridge 14 is installed in the multifunction device, the ink may be most susceptible to the effects of gravity when ink cartridge 14 is installed in the multifunction device, therefore, even if the ink has adhered to detection surfaces 140a and 140b, it drops relatively quickly. It therefore may be possible to substantially avoid the transfer of ink to the light receiving portion and the light emitting portion of the sensor. Moreover, the ink which drops from detection surfaces 140a and 140b may not adhere to the end surface of ink supply portion 120.
Referring to FIG. 5(c), side walls which form detection walls 140a and 140b extending from the side surface of frame portion 110 may be provided on translucent portion 140. Therefore, an edge portion 140c where the side surface of frame portion 110 and detection surfaces 140a and 140b intersect may be provided at a substantially perpendicular angle. When ink adheres to the vicinity of edge 140c, the capillary force of edge 140c acts upon the ink because edge 140c may be provided at a substantially perpendicular angle, and the ink may flow towards the side of ink supply portion 120 along edge 140c. It therefore may be possible to reduce the adherence of ink to detection surfaces 140a and 140b. 
When ink cartridge 14 is installed in the multifunction device, ink cartridge 14 may be installed, such that ink supply portion 120 is located below ambient air intake portion 130. This state may be the installation position of ink cartridge 14. Moreover, when ink cartridge 14 is installed in the multifunction device, ink supply portion 120, translucent portion 140, and ambient air intake portion 130 may be sequentially positioned from bottom to top, and ink supply portion 120, translucent portion 140, and ambient air intake portion 130 may be provided on a single end surface. Therefore, because ink supply portion 120, translucent portion 140, and ambient air intake portion 130 are provided, such that they are focused, e.g., positioned adjacent to each other, on a single end surface, the sensor, a needle (not shown) configured to be connected with ink supply portion 120, and a passage (not shown) configured to be connected with ambient air intake portion 130 associated with the multifunction device may be consolidated on a single surface, such that the size of the multifunction device may be reduced.
Ink supply portion 120 and translucent portion 140 may be sequentially provided on the single end surface from top to bottom, and by using movable member 470 for detecting ink, the ink may be used to the fullest extent. For example, when the amount of ink is detected by irradiating a portion of the ink cartridge using a photo-detector, if a method in which the presence of ink may be detected directly were used, the ink could not be fully used with a configuration in which the ink supply opening and the irradiated portion which may be irradiated by photo-detector are both provided on a single end surface, as in this embodiment. Specifically, if the irradiated portion is positioned below the ink supply opening, the position of the ink supply opening becomes relatively high, such that ink which is stored below the ink supply opening may not be used. Conversely, if the irradiated portion is positioned above the ink supply opening, the position of the irradiated portion becomes relatively high, such that a significant quantity of ink may be inside the ink cartridge when the photo-detector detects the absence of ink. Nevertheless, in this embodiment, movable member 470 may be used, such that even when the irradiated portion is provided in a relatively high position, the absence of ink may be detected in step with the timing in which the actual amount of ink becomes low, and the ink supply opening may be provided in a low position, such that there may be an insignificant amount of ink inside the ink cartridge when the absence of ink is detected.
Referring to FIGS. 3(a), 8(a), and 8(b), when ink cartridge 14 is installed in the multifunction device, the light emitting portion and the light receiving portion of the sensor may be positioned at positions sandwiching translucent portion 140. Because signal blocking portion 473c of movable member 470 may be positioned in enclosure portion 141 of translucent portion 140, the ink quantity may be detected by the operation of movable member 470.
The direction of rotation of movable member 470 may be determined based on the combined force of the buoyancies and gravities acting on the right side portion and the left side portion. Nevertheless, in order to simply the description of sensor 470, it is assumed that all of the forces which act on movable member 470 also act on float portion 471. Based on this assumption, the rotation of movable member 470 is determined by the buoyancy and the gravity acting on float portion 471. When there is a large amount of ink stored in ink chamber 111, because float portion 471 of movable member 470 may comprise resin material with a lower specific gravity than the specific gravity of ink, the buoyancy generated on float portion 471 increases, and float portion 471 floats in the ink. The combined force of gravity and buoyancy generated on float portion 471 causes a rotating force to be received in the clockwise direction in FIGS. 3(a), 8(a), and 8(b). Nevertheless, signal blocking portion 473c contacts arm supporting portion 142, and thus, signal blocking portion 473c may be positioned in a position blocking the optical path between the light emitting portion and the light receiving portion of the sensor.
As the ink within ink chamber 111 decreases in quantity, the surface level I of the ink drops. As the surface level I of the ink drops, signal blocking portion 473c emerges on the surface level I of the ink, and subsequently, float portion 471 also emerges on the surface level I of the ink. When float portion 471 emerges on the surface level I of the ink, the buoyancy generated on float portion 471, which causes movable member 470 to rotate in the clockwise direction in FIGS. 3(a), 8(a), and 8(b), and the gravity generated on float portion 471, which causes movable member 471 to rotate in the counterclockwise direction in FIGS. 3(a), 8(a), and 8(b), balance each other out, such that the overall combined force may be balanced. Subsequently, as the surface level I of the ink drops further, float portion 471 moves downward following the surface level I, such that movable member 470 rotates counterclockwise. The rotating operation causes signal blocking portion 473c to move upward away from arm supporting portion 142, and an optical path may be created between the light emitting portion and the light receiving portion of the sensor. In this state, a controller (not shown) of the multifunction device determines that ink cartridge 14 is out of ink.
As the quantity of ink transitions from a substantial amount of ink to substantially no ink, float portion 471 may transition from an upper position to a lower position within ink chamber 111. Thus, when the quantity of ink in ink chamber 111 is low, an out-of-ink discrimination accurately may be detected.
Referring to FIG. 6, a communication path 116 may be formed within ink cartridge 14, and ink may flow through communication path 116 as indicated by the arrow K. Communication path 116 may be in fluid communication with ink chamber 111 and ink supply portion 120, and may be configured to dispense ink from an interior of ink chamber 111 to an exterior of ink chamber 111 via an opening formed in ink supply portion 120. Communication path 116 may be substantially perpendicular to the wall on which ink supply portion 120, ambient air intake portion 130, and translucent portion 140 are formed.
Referring to FIG. 9(a), an ink cartridge 4014 according to yet another embodiment of the present invention is depicted. Ink cartridge 4014 may have a through-hole 4130 for admitting ambient air into ink cartridge 4014 provided in a portion of its top surface. The air admitted through through-hole 4130 may pass through a labyrinth shaped air intake passage 4131 and may be admitted within ink cartridge 4014. A seal member 4132 may be glued to ink cartridge 4014 to prevent deaeration and outflow of ink within ink cartridge 4014 before use. To use ink cartridge 4014, seal member 4132 may be peeled off, and then the cartridge is installed the multifunction device.
A portion 4140 may be a protrusion provided outward from one end surface extending substantially in the vertical direction of ink cartridge 4014, and below which may be provided ink supply portion 4120. Portion 4140 may be translucent. An ink supply opening 4121 into which a needle of the multifunction device may be inserted may be provided on the protrusion tip of ink supply portion 4120. Ink cartridge 4014 may not have a structure corresponding to ink reservoir element 100, and stores the ink directly within the case. A movable member like movable member 470 may be provided within ink cartridge 4014 and a signal blocking portion of the movable member may be positioned within portion 4140. Alternatively, portion 4140 may not be translucent, e.g. opaque, and the movable member may not be within the ink cartridge. In this case, an ink amount in ink cartridge 4014 may not be detected by the sensor. However, at least presence and absence of ink cartridge 4014 may be detected by the sensor because portion 4140 blocks the light emitted from the light emitting portion of the sensor when ink cartridge 4014 is installed in the multifunction device.
Referring to FIG. 9(b), an ink cartridge 5014 according to still yet another embodiment of the present invention is depicted. Ink cartridge 5014 may be substantially the same as ink cartridge 4014, except that ink supply portion 4120 has been replaced by ink supply portion 5120.
Referring to FIG. 10, an ink reservoir element 9300 according to another embodiment of the present invention is depicted. Ink reservoir element 9300 may be substantially similar to ink reservoir element 100. Therefore, only the differences between ink reservoir element 9300 and ink reservoir element 100 are discussed with respect to ink reservoir element 9300. Ink reservoir element 9300 may be fixed within the first and second case members. Ink reservoir element 9300 may comprise a hard portion 9301 which may be provided through injection molding using a resin material, and a bag element 9302 connected to hard portion 9301, which may be a flexible element which forms a reservoir space for storing ink therein. Hard portion 9301 may comprise a detection portion 9303 which may be configured to be positioned between the light emitting portion and the light receiving portion of the sensor. In operation, when the ink within bag portion 9302 is reduced, bag portion 9302 may shrink in response to the reduction in ink, and the ink is substantially depleted, the reservoir space also may be substantially depleted. Therefore, it may be difficult to position a movable member within bag portion 9302 to detect the amount of ink remaining within bag portion 9302.
Moreover, hard portion 9301 may have light barrier properties, and because it may be positioned between the light emitting portion and the light receiving portion, it may block the emitted light which is emitted from the light emitting portion. Therefore, it may be possible to detect whether there is an ink reservoir element 9300 contained within the first and second case members, and as such, it may be possible to prevent printing processes from being performed by the multifunction device when no ink reservoir 9300 is present.
While the invention has been described in connection with exemplary embodiments, it will be understood by those skilled in the art that other variations and modifications of the exemplary embodiments described above may be made without departing from the scope of the invention. Other embodiments will be apparent to those skilled in the art from a consideration of the specification or practice of the invention disclosed herein. It is intended that the specification and the described examples are considered merely as exemplary of the invention, with the true scope of the invention being indicated by the flowing claims.

## Claims

1. An ink cartridge, comprising:
a first case comprising a wall having a first end and a second end opposite the first end, wherein the wall has a first opening and a second opening formed therethrough, the first opening has a first center, and the second opening has a second center, wherein the wall has a first center line and a second center line which is perpendicular to the first center line, and each of the first center and the second center is offset from each of the first center line and the second center line;
a second case enclosed within the first case;
an ink supply portion extending from the second case and positioned adjacent to the second end of the wall, wherein at least a portion of the ink supply portion is configured to be received by the first opening; and
a protruding portion extending from the second case and positioned at the wall between the first end of the wall and the ink supply portion, wherein at least a portion of the protruding portion is aligned with the second opening and exposed to an outside of the second case, and the protruding portion is opaque,
wherein the wall further comprises a third opening formed therethrough, and the third opening has a third center which is offset from each of the first center line and the second center line, wherein the ink cartridge further comprises an air intake portion extending from the second case and positioned at the wall between the first end of the wall and the protruding portion, wherein at least a portion of the air intake portion is configured to be received by the third opening.

2. The ink cartridge of claim 1, further comprising at least one protrusion extending from at least one of the first end of the wall and the second end of the wall, wherein the at least one protrusion has a fourth center which is offset from each of the first center line and the second center line.