EP2039519B1

EP2039519B1 - Liquid container

Info

Publication number: EP2039519B1
Application number: EP08003711A
Authority: EP
Inventors: Shingo Hattori
Original assignee: Brother Industries Ltd
Current assignee: Brother Industries Ltd
Priority date: 2008-02-28
Filing date: 2008-02-28
Publication date: 2009-11-25
Anticipated expiration: 2028-02-28
Also published as: EP2039519A1; DE602008000324D1; ATE449685T1

Abstract

A liquid container includes a case, a liquid supply portion, and a movable member. The case defines a liquid chamber which is configured to store a predetermined amount of liquid. The liquid supply portion is configured to dispense liquid from the liquid chamber. The movable member is pivotably positioned within the liquid chamber, and includes a signal blocking portion, a float portion, and an arm portion. The arm portion includes a pivot center, a first portion, and a second portion. The movable member is configured to pivot about the pivot center. The first portion is connected to the signal blocking portion and the pivot center, and the second portion is connected to the float portion and the pivot center. When the liquid chamber stores the predetermined amount of liquid, at least a portion of the first portion is positioned higher than the signal blocking portion.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a liquid container comprising a movable member which indicates whether an amount of ink stored in the liquid container is a sufficient amount of ink.

2. Description of Related Art

A known ink-jet printer is configured to eject ink onto a sheet of paper to record an image on the sheet of paper. The known ink-jet printer has a recording head. The recording head is configured to selectively eject ink from nozzles to the sheet of paper. A known ink cartridge is configured to be removably mounted to the ink-jet printer. The ink cartridge has an ink chamber configured to store ink therein, and ink is supplied from the ink chamber to the recording head when the ink cartridge is mounted to the ink-jet printer.
The ink cartridge has a movable member disposed in the ink chamber. The movable member is configured to pivot based on the amount of ink stored in the ink chamber. When the ink is consumed and the amount of ink in the ink chamber becomes less than a sufficient amount of ink, an end of the movable member moves from a first position at which the end of the movable member is detected by a detector e.g., an optical sensor, to a second position at which the end of the movable member is not detected by the detector. Consequently, whether the ink chamber has a sufficient amount of ink stored therein may be determined based on the position of the end of the movable member. Such a known ink cartridge is described in JP-A-2005-262564 for example.
The movable member is submerged in ink when the ink chamber has an amount of ink which is substantially greater than a sufficient amount of ink. As the ink in the ink chamber gradually decreases, the movable member gradually becomes exposed above the surface of ink. When the movable member is exposed from the surface of ink, a web-shaped film of ink or a balloon-shaped film of ink may be formed between the movable member and the surface of ink. The film may inhibit or restrict the pivotal motion of the movable member, and the end of movable member may not be detected accurately. Such a container is shown in EP 1 772 270 A2 which discloses the preamble of claim 1. For example, when the movable member attempts to pivot away from the surface of ink, the film may pull the movable member towards the surface of ink. This problem may arise in known ink cartridges or in any known liquid container.

SUMMARY OF THE INVENTION

Therefore, a need has arisen for a liquid containers, such as a ink cartridge, which overcomes these and other shortcomings of the related art. A technical advantage of the present invention is that a movable member readily pivots in a direction away from a surface of liquid.
According to an embodiment of the present invention, a liquid container comprises a case, a liquid supply portion, and a movable member. The case is configured to define at least a portion of a liquid chamber therein, and the liquid chamber is configured to store a predetermined amount of liquid therein. The liquid supply portion is configured to dispense liquid from an interior of the liquid chamber to an exterior of the liquid chamber, and the liquid supply portion has a center line which is parallel to the predetermined direction. The movable member is pivotably positioned within the liquid chamber, and the movable member comprises a signal blocking portion, a float portion, and an arm portion. The arm portion comprises a pivot center, a first portion, and a second portion. The movable member is configured to pivot about the pivot center. The first portion is connected to the signal blocking portion and the pivot center, and the second portion is connected to the float portion and the pivot center. Moreover, when the liquid chamber contains a sufficient amount of liquid to submerge the float portion, at least a portion of the first portion is positioned higher than the signal blocking portion.
The last sentence of the previous paragraph means that at least a portion of the first portion is positioned higher than the signal blocking portion when the liquid container is positioned in a in-use orientation. The in-use orientation is an orientation in which the liquid container is positioned when the liquid container is used to dispense liquid to the exterior of the liquid chamber via the liquid supply portion. If the liquid container is used as a cartridge, such as an ink cartridge, configured to be mounted to a main device, such as an inkjet printer, the in-use orientation is an orientation in which the liquid container is positioned when the liquid container is mounted to the main device. With this configuration, even when liquid in the liquid chamber is gradually consumed and the movable member becomes exposed to air, the at least a portion of the first portion is exposed to air before the signal blocking portion is exposed to air. Therefore, the possibility of the formation of the film of liquid between the movable member and the surface of liquid is less than in the known liquid containers. Moreover, even if such a film of liquid is formed, the film of liquid is broken from the at least a portion of the first portion. Consequently, the pivotal movement of the movable member away from the surface of liquid is smoothened.
When the liquid chamber contains a sufficient amount of liquid to submerge the float portion, the pivot center may be positioned lower than the signal blocking portion. With this configuration, the first portion extends upward from the signal blocking portion and then downward to the pivot center. Therefore, the first portion does not extend straight, i.e., the first portion is bent. It may be more difficult for the film of liquid to form between the surface of liquid and the bent surface of the first portion than between the surface of liquid and a straight surface of the first portion, or the film of liquid may be broken more easily between the surface of liquid and the bent surface of the first portion than between the surface of liquid and a straight surface of the first portion.
The first portion may comprise a first sub-portion connected to the signal blocking portion, and a second sub-portion connected to the first sub-portion and the pivot center. An angle formed between the first sub-portion and the second sub-portion may be an acute angle. It may be more difficult for the film of liquid to form between the surface of liquid and the surface of the first portion having the acute angle than between the surface of liquid and a straight surface of the first portion, or the film of liquid may be broken more easily between the surface of liquid and the surface of the first portion having the acute angle than between the surface of liquid and a straight surface of the first portion.
The liquid container further may comprise a translucent portion extending away from the liquid chamber. The translucent portion may have an inner space formed therein, and the inner space may be configured to be in liquid communication with the liquid chamber. The movable member may be configured to pivot within the liquid chamber between a first position and a second position based on an amount of liquid in the liquid chamber. When the movable member is in the first position, the signal blocking portion may be positioned within the inner space, and when the movable member is in the second position, at least a portion of the signal blocking member may be positioned outside the inner space. With this configuration, by monitoring the position of the signal blocking portion through the translucent portion, it may be determined whether the liquid chamber stores a sufficient amount of liquid.
The movable member may comprise a plurality of projections extending from an outer peripheral surface of the movable member. The projections may break the film of liquid.
Each of the plurality of projections may have a base connected to the outer peripheral surface of the movable member, and a peak, and a thickness of the base is greater than a thickness of the peak. The peak of each of the projections may break the film of liquid more easily.
At least a portion of the plurality of projections may extend in a direction parallel to a direction in which the first portion pivots. The projections may break the film of liquid when the movable member pivots.
The movable member may have a width and a length which is greater than the width of the movable member, and a distance between a first end of the movable member and a second end of the movable member corresponds to the width of the movable member. The movable member may comprise a plane surface having the first end of the movable member and the second end of the movable member, and the plane surface is slanted and not perpendicular with respect to a direction in which the movable member pivots. Because the plane surface is slanted and not perpendicular with respect to a direction in which the movable member pivots, the first or second end may break the film of liquid when the movable member pivots.
The movable member may comprise a plurality of projections extending from the plane surface. The projections may break the film of liquid.
Other features and technical advantages of the present invention will be apparent to persons of ordinary skill in the art in view of the following detailed description of the invention and the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

For a more complete understanding of the present invention, the needs satisfied thereby, and the objects, features, and advantages thereof, reference now is made to the following description taken in connection with the accompanying drawings.
Figs. 1 (a) and 1 (b) are a front-face perspective view and a rear-face perspective view of an ink cartridge, respectively, according to an embodiment of the present invention.
Fig. 2 is a side view of the ink cartridge of Figs. 1(a) and 1(b), in which a right side wall of a main body of the ink cartridge is removed.
Fig. 3 is a cross-sectional view of the ink cartridge taken along a line III-III of Fig. 1(a).
Fig. 4 is a perspective view of a movable member, according to an embodiment of the present invention.
Figs. 5(a)-5(c) is a left side view, a front view, and a right side view of the movable member of Fig. 4, respectively..
Fig. 6 is a cross-sectional view of the movable member taken along a line VI-VI in Fig. 5(c).

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention and their features and technical advantages may be understood by referring to Figs. 1(a)-6, like numerals being used for like corresponding portions in the various drawings.
Referring to Figs. 1(a) and 1(b), an ink cartridge 10, according to an embodiment of the present invention, is depicted. The ink cartridge 10 is configured to be used in combination with an ink-jet printer. The ink cartridge 10 is configured to be removably mounted to a mounting portion of the printer. When the ink cartridge 10 is mounted to the mounting portion, ink is supplied from the ink cartridge 10 to a recording head (not shown) of the printer.
The ink cartridge 10 has a substantially flat, hexahedron shape. A width of the ink cartridge 10, as indicated by an arrow 31, is relatively short, and each of a height of the ink cartridge 10, as indicated by an arrow 32, and a depth of the ink cartridge 10, as indicated by an arrow 33, is greater than the width of the ink cartridge 10. The ink cartridge 10 is inserted into a printer in a direction indicated by an arrow 30.
Referring to Figs. 1(a)-3, the ink cartridge 10 comprises a case, e.g., a main body 20, a movable member 70, and an ink supply portion 90. The main body 20 defines an ink chamber 100 therein for storing ink. The main body 20 is formed of a translucent resin material, such as a transparent or semi-transparent resin material, e.g., a resin comprising polyacetal, nylon, polyethylene, polypropylene, or the like, or any combination thereof, to allow light to pass therethrough. The main body 20 comprises a front wall 41, a rear wall 42, a top wall 43, and a bottom wall 44. The main body 20 also comprises a pair of side walls 45 and 46 which oppose each other, and each of the side walls 45 and 46 is connected to the front wall 41, the rear wall 42, the top wall 43, and the bottom wall 44. Each of the side walls 45 and 46 has a surface area which is greater than each of a surface area of the front wall 41, a surface area of the rear wall 42, a surface area of the top wall 43, and a surface area of the bottom wall 44. The main body 20 further comprises inner walls 52 positioned within the ink chamber 100 and extending from one of the side walls 45 and 46 to the other of the side walls 45 and 46 to reinforce the rigidity of the main body 20. When the ink cartridge 10 is mounted to the printer, the ink cartridge 10 is positioned in an in-use orientation. When the ink cartridge 10 is positioned in the in-use orientation, the top wall 43 is positioned above the bottom wall 44 as in Figs. 2 and 3.
The ink supply portion 90 is positioned at the front wall 41 at a position adjacent to the bottom wall 44. A valve (not numbered, but shown in Fig. 3) may be disposed within the ink supply portion 90. When the ink cartridge is not mounted to the mounting portion of the printer, the valve is closed, and fluid communication between the interior of the ink chamber 100 and the exterior of the ink cartridge 10 via the ink supply portion 90 is prevented. When the ink cartridge is mounted to the mounting portion of the printer, a pipe (not shown) positioned in the mounting portion enters the ink supply portion 90 and applies a force to the valve to open within the ink supply portion 90. When the valve is opened, the ink chamber 100 is brought into fluid communication with the exterior of the ink cartridge 10 via the ink supply portion 90, and ink is supplied from the interior of the ink chamber 100 to a recording head of the printer via the pipe. The ink supply portion 90 has a center line C extending in a predetermined direction, and the ink supply portion 90 extends away from the ink chamber 100 along the center line C.
A translucent portion 140 is positioned at the front wall 41 of the main body 20 and extends away from the ink chamber 100 in a direction parallel to the predetermined direction. An amount of ink stored in the ink chamber 100 is optically or visually detected through the translucent portion 140. The translucent portion 140 is integral with the main body 20, and is formed of the same material as the main body 20.
The translucent portion 140 extends outward from a center portion of the front wall 41 of the main body 20 in the direction parallel to the predetermined direction away from the ink chamber 100. The translucent portion 140 comprises five rectangular walls, and has a substantially a hollow box shape. For example, the translucent portion 140 comprises a front wall 140a, a pair of side walls 140b, a top wall 140c, and a bottom wall 140d. The front wall 140a extends parallel to the front wall 41 and is separated from the front wall 41 by a predetermined distance. The pair of side walls 140b are connected to the front wall 41 and the front wall 140a, the top wall 140c is connected to top ends of the front wall 140a and the side walls 140b, and the bottom wall 140d is connected to bottom ends of the front wall 140a and the side walls 140b. Moreover, the width of the front wall 140a is less than the width of the front wall 41.
When the ink cartridge 10 is mounted to the printer, the translucent portion 140 is configured to be sandwiched between a light-emitting element (not shown) and a light-receiving element (not shown) of an optical sensor (not shown), e.g. a photo interrupter, which is positioned in the printer. Light emitted by the light-emitting element may pass through the side walls 140b, and may be received by the light-receiving element.
The translucent portion 140 has an inner space 142 formed therein, which is defined by the front wall 140a, the side walls 140b, the top wall 140c and the bottom wall 140d. The inner space 142 is configured to be in fluid communication with the interior of the ink chamber 100, e.g., there is no wall positioned between the inner space 142 and the ink chamber 100. The movable member 70 is configured to move between a first position and a second position based on an amount of ink within the ink chamber 100. When the movable member 70 is in the first position, a signal blocking portion 72 of the movable member 70 is positioned within the inner space 142, as indicated by a solid line in Fig. 3. When the movable member 70 is positioned in the second position, at least a portion of the signal blocking portion 72 is positioned outside the inner space 142, as indicated by a dotted line in Fig. 3.
The movable member 70 is configured to indicate whether the ink chamber 100 has a sufficient amount of ink stored therein. The movable member 70 comprises the signal blocking portion 72, a float portion 73, and an arm portion (not numbered). The signal blocking portion 72 is connected to the float portion 73 via the arm portion. The movable member 70 is pivotably supported at a rib 74 extending from a portion of the main body 20 adjacent to a corner of the front wall 41 and the bottom wall 44. The arm portion comprises a pivot center, e.g., a middle portion (not numbered) having a shaft hole 78 formed therethrough, and the rib 74 comprises a supporting shaft 77 extending through the shaft hole 78, such that the movable member 70 pivots about the middle portion of the arm portion, i.e., about the supporting shaft 77 and the shaft hole 78.
Referring to Figs. 2-6, the movable member 70 and the movement of the movable member 70 are described. In Fig. 6, the cross-sectional surface is illustrated by a solid line, a projection 65 is illustrated by a bold line, and other portions of the movable member 70 are illustrated by dotted lines.
The arm portion of the movable member 70 comprises a first portion 75 connected to the middle portion of the arm portion at one end, and connected to the signal blocking portion 72 at the other end. The arm portion of the movable member 70 also comprises a second portion 76 connected to the middle portion of the arm portion at one end, and connected to the float portion 73 at the other end. The first portion 75 extends from the middle portion of the arm portion to the left in Fig. 3, and the second portion 76 extends from the middle portion of the arm portion to the right in Fig. 3. The shaft hole 78 extends in a direction perpendicular to the paper plane of Fig. 3, and the supporting shaft 77 extends in the direction perpendicular to the paper plane of Fig. 3. Each of the shaft hole 78 and the supporting shaft 77 has a center line extending in the direction perpendicular to the paper plane of Fig. 3. The movable member 70 is configured to pivot in a particular plane parallel to the paper plane of Fig. 3 as indicated by an arrow 35 in Fig. 3.
The specific gravity of the float portion 73 is less than the specific gravity of ink stored in the ink chamber 100. The float portion 73 has a hollow formed therein, and the float portion 73 floats on liquid, such that the float portion 73 moves upward and downward based on the amount of ink within the ink chamber 100. The movable member 70 pivots based on the movement of the float portion 73. In another embodiment, the float portion 73 may not have the hollow, and may be formed of a material having a specific gravity less than the specific gravity of ink.
The signal blocking portion 72 is configured to indicate whether the ink chamber 100 has a sufficient amount of ink stored therein. When the movable member 70 pivots counterclockwise in Fig. 3, the signal blocking portion 72 moves into the inner space 142 and contacts the bottom wall 140d, such that further movement of the movable member 70 is prevented and the movable member 70 remains in the first position. Similarly, when the movable member 70 pivots clockwise in Fig. 3, the signal blocking portion 72 moves away from the bottom wall 140d, and at least a portion of the signal blocking portion 72 moves out of the inner space 142. When the float portion 73 contacts a bottom surface of the ink chamber 100, further movement of the movable member 70 is prevented and movable member 70 remains in the second position, in which the signal blocking portion 72 is separated from the bottom wall 140d by a predetermined distance.
The signal blocking portion 72 comprises a plurality of pin members 131 and 132. The pin member 131 is positioned at an upper front end of the signal blocking portion 72. The pin member 132 is positioned at the lower end of the signal blocking portion 72. Each of the pin members 131 and 132 has a column shape and is integral with the movable member 70. Each of the pin members 131 and 132 extends in a width direction of the signal blocking portion 72, i.e., extends left to right in Fig. 5(b). Each of the pin members 131 and 132 projects from both sides of signal blocking portion 72 towards side walls 140b. If the signal blocking portion 72 moves in the width direction, the pin members 131 and 132 contact the side wall 140b, and signal blocking portion 72 does not contact the side wall 140b. Consequently, the distance between the signal blocking portion 72 and the side walls 140b is maintained within a predetermined distance range. Therefore, the movement of the signal blocking portion 72 is smoothened without being affected by the surface tension of the ink between the side walls 140b and the signal blocking portion 72, and the width of the translucent portion 140 can be made relatively narrow.
Ends 134 of the pin members 131 and 132 are spherical. Therefore, even if the ends 134 of the pin member 131 and 132 contact the side wall 140b, it is a single point of contact. Therefore, the movement of the signal blocking portion 72 is not be significantly affected by such contact between the pin member 131 and 132 and the side wall 140b. Moreover, even if ink is left between the ends 134 of the pin members 131 and 132 and the side wall 140b after the ink is removed from the translucent portion 140 as the ink level in the ink chamber 100 is lowered, the amount of ink left therebetween is an insignificant amount of ink. Therefore, the movement of the signal blocking portion 72 in the translucent portion 140 is smoothened without being affected by the left ink.
The mass of the first portion 75 is less than the mass of the second portion 76. Therefore, the second portion 76 is heavier than the first portion 75 in air. Accordingly, when the ink chamber 100 does not have a sufficient amount of ink, e.g., when the ink chamber 100 is empty of ink, the movable member 70 pivots clockwise about the supporting shaft 77 and the shaft hole 78 in Fig. 3, and at least a portion of the signal blocking portion 72 moves out of the inner space 142. When the lower end of the float portion 73 contacts the bottom surface of the ink chamber 100, the movable member 70 stops pivoting and the movable member 70 remains in the second position. When the movable member 70 is in the second position, in which the signal blocking portion 72 does not contact the bottom wall 140d, it is determined that the ink chamber does not have a sufficient amount of ink.
When the ink chamber 100 has a sufficient amount of ink therein, and the float portion 73 is submerged in the ink, a buoyancy force acts on the float portion 73. This buoyancy force is great enough to cause the movable member 70 to pivot counterclockwise about the supporting shaft 77 and the shat hole 78 in Fig. 3. When the movable member 70 pivots counterclockwise, the signal blocking portion 72 moves into the inner space 142. When the lower end of the signal blocking portion 72 contacts the bottom wall 140d, the movable member 70 stops pivoting and the movable member 70 remains in the first position. When the movable member 70 is in the first position, in which the signal blocking portion 72 contacts the bottom wall 140d, it is determined that the ink chamber has a sufficient amount of ink.
Whether or not the ink chamber 100 has a sufficient amount of ink stored therein is determined by a user viewing the position of the signal blocking portion 72 in the inner space 142, or by using an optical sensor e.g., a photo interrupter, to monitor the position of the signal blocking portion 72.
Referring to Fig. 3, when the ink cartridge 10 is positioned in the in-use orientation, and when the ink chamber 100 has a sufficient amount of ink therein such that the movable member 70 is in the first position, at least a portion of the first portion 75 is positioned higher than the signal blocking portion 72, the middle portion of the arm portion is positioned lower than the signal blocking portion 72, and the at least a portion of the first portion 75 is positioned further from the center line C of the ink supply portion 90 than the signal blocking portion 72 is positioned from the center line C of the ink supply portion 90. In particular, a bent portion 71 of the first portion 75 is positioned higher than the signal blocking portion 72, and the bent portion 72 is positioned further from the center line C of the ink supply portion 90 than the signal blocking portion 72 is positioned from the center line C of the ink supply portion 90.
Referring to Figs. 4-6, the first portion 75 comprises a first sub-portion 63 and a second sub-portion 62. Each of the first and second sub-portions 63 and 62 has a first end and a second end. The first end of the first sub-portion 63 is connected to the signal blocking portion 72, the second end of the first sub-portion 63 is connected to a first end of the second sub-portion 62, and the second end of the second sub-portion 63 is connected to the middle portion of the arm portion. The first sub portion 62 and the second sub portion 63 forms an acute angle corner therebetween, and the corner of the first sub portion 62 and the second sub portion 63 corresponds to the bent portion 71.
The first portion 75 is a thin plate. The first portion 75 has a first end 201, a second end 202, a third end 203, and a fourth end 204 as shown in Fig. 6. The first portion 75 comprises a first plane surface 66 having the first end 201 and the second end 202, a second plane surface 166 having the third end 203 and the fourth end 204, a right-side plane surface having the first end 201 and the third end 203, and a left-side plane surface having the second end 202 and the fourth end 204. The first plane surface 66 and the left-side plane surface forms an acute angle at the second end 202, and the second plane surface 166 and the lest-side plane surface forms an acute angle at the fourth end 204. The first portion 75 has a first width corresponding to a distance between the first end 201 and the second end 202, and a second width corresponding to a distance between the third end 203 and the fourth end 204. The first portion 75 has a length in a direction perpendicular to the first width and the second width of the first portion 75, and the length of the first portion 75 is greater than the first width and the second width of the first portion 75.
The first portion 75 comprises ribs 64 formed on the left-side plane surface and the right-side plane surface of the first portion 75, respectively. The ribs 64 extends from the bent portion 71 towards the signal blocking portion 72. The ribs 64 reinforce the rigidity of the first portion 75.
The first portion 75 also comprises a plurality of the projections 65 extending from an outer peripheral surface of the first portion 75 and positioned at a predetermined interval from a portion adjacent to the shaft hole 78 to a portion adjacent to the signal blocking portion 72. More specifically, the projections 65 extend from the first plane surface 66 and the second plane surface 166 of the first portion 75 in a direction parallel to a direction in which the first portion 75 pivots. The projections 65 breaks or pop a film of ink formed between the first portion 75 and the surface of ink, or prevents the film of ink from being formed between the first portion 75 and the surface of ink. The first plane surface 66 and the second plane surface 166 of the first portion 75 are slanted and not perpendicular with respect to the direction in which the first portion 75 pivots. Each of the plurality of projections 65 has a base connected to the first plane surface 66 or to the second plane surface 166, and a peak. Moreover, a thickness of the base is greater than a thickness of the peak.
Referring to Figs. 1(a), 1(b) and 3, an air intake hole 80 is formed through the top wall 43. Before the ink cartridge 10 is used, a sticker (not shown) is be placed on the top wall 43 to cover the air intake hole 80, and fluid communication between the interior of the ink chamber 100 and the exterior of the ink cartridge 10 via the air intake hole 80 is prevented. When a user intends to use the ink cartridge 10, the user removes the sticker from the top wall 43, and thereby the ink chamber 100 is brought into fluid communication with the exterior of the ink cartridge 10 via the air intake hole 80.
. When the ink cartridge 1 0 is mounted to a printer, the bent portion 71 of the first portion 75 is positioned above the signal blocking portion 72. Therefore, even when ink in the ink chamber 100 is gradually consumed and the movable member 70 becomes exposed to air, the possibility of the formation of the film of ink between the movable member 70 and the surface of ink or between the inner walls 52 and the movable member 70 is less than in the known ink cartridges. Moreover, even if such a film of ink is formed, the film of ink is broken from the bent portion 71. Consequently, the pivotal movement of the movable member 70 away from the surface of ink is smoothened.
Moreover, since the plurality of projections 65 are formed on the first portion 75 of the movable member 70, even if the film of ink is formed between the movable member 70 and the surface of ink or between the inner walls 52 and the movable member 70, the film of ink is broken or popped by the projections 65.
In another embodiment, the projections 65 may not be formed. Even in this case, the film of ink is broken because the acute angles are formed between the first plane surface 66 and the left-side plane and between the second plane surface 166 and the lest-side plane surface.
In another embodiment, the present invention may be applied also to liquid containers configured to store liquid other than ink, e.g., a viscous liquid.
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 as claimed.

Claims

A liquid container (10) comprising:
a case (20) configured to define at least a portion of a liquid chamber (100) therein, and the liquid chamber (100) is configured to store a predetermined amount of liquid therein;

a liquid supply portion (90) configured to dispense liquid from an interior of the liquid chamber (100) to an exterior of the liquid chamber (100); and a movable member (70) pivotably positioned within the liquid chamber (100), wherein the movable member (70) comprises:
a signal blocking portion (72);

a float portion (73); and

an arm portion comprising:
a pivot center wherein the movable member (70) is configured to pivot about the pivot center;

a first portion (75) connected to the signal blocking portion (72) and the pivot center; and

a second portion (76) connected to the float portion (73) and the pivot center, characterized in that, when the liquid chamber (100) contains a sufficient amount of liquid to submerge the float portion (73), at least a portion of the first portion (75) is positioned higher than the signal blocking portion (72).
The liquid container (10) of claim 1, wherein the pivot center is positioned lower than the signal blocking portion (72).
The liquid container (10) of claims 1 or 2, wherein the first portion (75) comprises a first sub-portion (63) connected to the signal blocking portion (72), and a second sub-portion (62) connected to the first sub-portion (63) and the pivot center, wherein an angle formed between the first sub-portion (63) and the second sub-portion (62) is an acute angle.
The liquid container (10) of any one of claims 1 to 3, further comprising a translucent portion (140) extending away from the liquid chamber, wherein the translucent portion (140) has an inner space (142) formed therein, and the inner space (142) is configured to be in liquid communication with the liquid chamber (100), wherein the movable member (70) is configured to pivot within the liquid chamber between a first position and a second position based on an amount of liquid in the liquid chamber (100), wherein when the movable member (70) is in the first position, the signal blocking portion (72) is positioned within the inner space (142), and when the movable member (70) is in the second position, at least a portion of the signal blocking member (72) is positioned outside the inner space (142).
The liquid container (10) of any one of claims 1 to 4, wherein the first portion (75) comprises a plurality of projections (65) extending from a plane surface (66) of the first portion (75).
The liquid container (10) of claim 5, wherein each of the plurality of projections (65) has a base connected to the plane surface (66) of the movable member (70), and a peak, and a thickness of the base is greater than a thickness of the peak.
The liquid container (10) of claim 5, wherein at least a portion of the plurality of projections (65) extend in a direction parallel to a direction in which the first portion (75) pivots.
The liquid container (10) of any one of claims 1 to 5, wherein the first portion (75) has a first end (201), a second end (202), a third end (203) and a fourth end (204), wherein the first portion (75) has a first width corresponding to a distance between the first end (201) and the second end (202), and a second width corresponding to a distance between the third end (203) and the fourth end (204), wherein the first portion (75) comprises the plane surface (66) having the first end (201) and the second end (202) of the first portion (75), and wherein the plane surface (66) is slanted and not perpendicular with respect to a direction in which the first portion (75) pivots.