Liquid storage container and method of manufacturing same

Abstract

To reduce the number of components of a liquid storage container.SOLUTION: A liquid storage container includes: a container body in which liquid may be stored, the container body having a frame part and a base part protruding from an inner wall surface of the frame member; a rotation member configured to rotate around a rotation axis by fluctuation of a liquid surface of the liquid, the rotation member having a float part, a display part configured to be visible from the outside, and a connection part which is connected with the float part and the display part and has a hole corresponding with the rotation axis; and a support member integrally formed with the base member and rotatably supporting the rotation member, the support member having a pin which is inserted into the hole and rotatably supports the rotation member, and displacement regulation parts which restrict displacement of the rotation member in a rotation axis direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a liquid storage container and a method for manufacturing the same. [Background technology]

[0002] A liquid ejection device that ejects liquid (ink) from a liquid ejection head onto a recording medium and records an image on the recording medium is provided with an ink tank that stores ink to be supplied to the liquid ejection head. Patent Document 1 discloses an ink tank that is capable of detecting the remaining amount of ink. Inside the ink tank, there are provided a bearing rib, a support block, a spindle supported by the bearing rib and the support block, and an arm rotatably supported by the spindle. The arm has a float portion and an indicator portion. When the float portion rotates due to buoyancy, the indicator portion rotates in conjunction with the float portion. The remaining amount of ink in the ink tank is detected by optically detecting the movement of the indicator portion. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-208268 A Summary of the Invention [Problem to be solved by the invention]

[0004] The liquid storage container disclosed in Patent Document 1 requires many parts due to a complex mechanism for detecting the remaining amount of liquid. Therefore, an object of the present invention is to provide a liquid storage container with a reduced number of parts. [Means for solving the problem]

[0005] The liquid storage container of the present invention is a container body capable of storing liquid therein, the container body having a frame portion and a base portion protruding from an inner wall surface of the frame portion; a rotating member that rotates around a rotation axis due to fluctuations in the liquid level, the rotating member having a float, a display portion configured to be visible from the outside, and a connection portion that connects the float and the display portion and has a hole that coincides with the rotation axis; and a support member that is formed integrally with the base portion and rotatably supports the rotating member, the support member having a pin that is inserted into the hole and rotatably supports the rotating member, and a rotation axis of the rotating member. Away from the base portion along The support member has a displacement restriction portion that restricts displacement in a direction. Effect of the Invention

[0006] According to the present invention, it is possible to provide a liquid storage container having a reduced number of parts. [Brief description of the drawings]

[0007] [Figure 1] 1 is an exploded perspective view of a liquid storage container according to a first embodiment of the present invention; [Diagram 2] 1 is a cross-sectional view of a liquid storage container according to a first embodiment of the present invention. [Diagram 3] FIG. 4 is a cross-sectional view of a liquid storage container according to a second embodiment of the present invention. [Figure 4] FIG. 11 is a cross-sectional view of a liquid storage container according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Some embodiments of the present invention will be described with reference to the drawings. In each drawing, the same reference numerals are used for the same components, and duplicated descriptions may be omitted. The embodiments described below are directed to an ink tank mounted on an inkjet printer, but the present invention can be widely applied to liquid storage containers mounted on liquid ejection devices. In this embodiment, "integrally formed" does not mean that a plurality of parts or members are integrated with an adhesive or fastening means, but rather means that the parts or members are manufactured as a single part or member from the beginning by means of injection molding or the like.

[0009] (First embodiment) FIG. 1 is an exploded perspective view of a liquid storage container 1A according to the first embodiment. FIG. 2 is a schematic cross-sectional view of the liquid storage container 1A according to the first embodiment, with the upper part of the figure showing the vertical upper side when the liquid ejection device is in use, and the lower part of the figure showing the vertical lower side when the liquid ejection device is in use. FIG. 2(a) is a side cross-sectional view, FIGS. 2(b) to (d) are schematic cross-sectional views showing a manufacturing method of the liquid storage container 1A, and FIG. 2(d) shows the completed liquid storage container 1A, that is, a cross-sectional view taken along line AA in FIG. 2(a). The liquid storage container 1A has a container body 2 capable of storing ink, a rotating member 3 housed inside the container body 2 and detecting the amount of ink, and a support member 4 rotatably supporting the rotating member 3.

[0010] The container body 2 has a frame member 21, a first film F1, and a second film F2. The frame member 21 is formed of a transparent or translucent light-transmitting material. The frame member 21 is integrally formed by injection molding synthetic resin such as polyacetal, nylon, polyethylene, or polypropylene. The frame member 21 has openings on both side surfaces perpendicular to the rotation axis of the rotating member 3. Specifically, the opening of the frame member 21 adjacent to a first displacement regulating portion 42 (described later) is a first opening 21A, and the opening of the frame member 21 adjacent to a second displacement regulating portion 43 (described later) is a second opening 21B. A light-transmitting protrusion 22 protruding upward is formed in the center of the upper side 21C of the frame member 21. The inside of the protrusion 22 is an internal space 26, and a tip portion 33A of a display member 33 (described later) is movably accommodated in the internal space 26. It is sufficient that at least a portion of the outer wall of the container body 2 has light-transmitting properties. As long as the protrusion 22 is made of a light-transmitting material, other portions of the frame member 21 may be made of a non-light-transmitting material.

[0011] The container body 2 has a base member 23 protruding from an inner wall surface 21D of the frame member 21. The base member 23 is formed integrally with the frame member 21. The base member 23 is a roughly L-shaped member fixed to one side wall and the bottom surface of the frame member 21. The base member 23 is provided mainly for mounting the rotating member 3 via the support member 4. The base member 23 also has a function of holding the first film F1 and a function of reinforcing the frame member 21 and increasing the rigidity of the frame member 21. The shape and position of the base member 23 are not limited, but it is preferable that the base member 23 is fixed to the frame member 21 at a plurality of positions on the inner wall surface 21D (in this embodiment, two adjacent sides of the frame member 21). This increases the rigidity of the frame member 21. The container body 2 has a plurality of ribs 24. The ribs 24 have a non-linear cross section to ensure rigidity. Some of the ribs 24 are fixed to the inner wall surface 21D of the frame member 21 and are formed integrally with the frame member 21. Some of the ribs 24 are fixed to the base member 23 and are formed integrally with the base member 23. That is, the frame member 21, the base member 23 and the ribs 24 are formed integrally by injection molding. The ribs 24 reinforce the frame member 21 and increase the rigidity of the frame member 21, and also have the function of holding the first and second films F1, F2. Some or all of the ribs 24 may be omitted. This reduces the cost of the liquid storage container 1A and increases the amount of ink that can be stored. A first protrusion 25 is formed on the surface of the base member 23 facing the rotating member 3. A gap G1 is provided between the tip 25A of the first protrusion 25 and a central connecting portion 31 (described later) of the rotating member 3.

[0012] The first film F1 and the second film F2 are made of a transparent resin. The first film F1 is welded to the periphery of the first opening 21A of the frame member 21 by a thermal welding method, and covers the first opening 21A of the frame member 21. The second film F2 is welded to the periphery of the second opening 21B of the frame member 21 by a thermal welding method, and covers the second opening 21B of the frame member 21. The space surrounded by the frame member 21 and the first and second films F1 and F2 forms an ink storage chamber 27 in which ink is stored. The first film F1 is also bonded to the base member 23 and the ribs 24 (except for the ribs 24 bonded to the base member 23), and the second film F2 is also bonded to all the ribs 24. As a result, the first and second films F1 and F2 are held at many locations, the bonding area is increased, and the reliability of the container body 2 is improved. Instead of providing the first and second films F1, F2, the container body 2 may be formed as a rectangular parallelepiped container, and the ink storage chamber 27 may be formed therein. An ink supply port 28 for supplying ink to the liquid ejection head is provided at the bottom of the ink storage chamber 27.

[0013] The rotating member 3 is a member for detecting the amount of ink stored in the ink storage chamber 27. The rotating member 3 has a central connector 31 having a rotation center C, a float 32 connected to the central connector 31, and an indication member 33 connected to the central connector 31. The indication member 33 extends substantially vertically upward from the rotation center C of the rotating member 3, and the float 32 extends substantially horizontally from the rotation center C below the indication member 33 in this embodiment. For this reason, the rotation moment that the rotating member 3 receives is determined mainly by the weight of the float 32 and the buoyancy that the float 32 receives. Since the indication member 33 hardly contributes to the rotation moment of the rotating member 3, there is a high degree of freedom in the material and shape of the indication member 33.

[0014] The central connector 31 is a generally circular plate-like member, and has a hole in the center, i.e., at the position of the rotation center C of the rotating member 3. The hole is a through hole 34 that penetrates the central connector 31, and functions as a bearing for the rotating member 3. A second protrusion 35 is formed on the peripheral surface of the central connector 31 that faces the second film F2. A gap G2 is provided between the tip 35A of the second protrusion 35 and the second film F2. The float 32 is supported by the central connector 31 and is an arm-like member that extends radially from the central connector 31. The float 32 is formed of a hollow resin, and the average specific gravity including the internal space is lower than the specific gravity of the ink. Therefore, the float 32 rotates due to the fluctuation of the ink level. Instead of the hollow float 32, a solid float 32 made of a material lower than the specific gravity of the ink may be used. In this case, the float 32 can be formed integrally with the central connector 31 and the display member 33. The indicator 33 is an arm-shaped member extending radially from the central connector 31, and is capable of externally indicating the position of the float 32. The indicator 33 is movably housed in the internal space 26 of the protrusion 22, and can rotate in the internal space 26 of the protrusion 22 in conjunction with the float 32 via the central connector 31. This allows the indicator 33 to indirectly indicate the position of the float 32 to the outside through the translucent outer wall 22A of the protrusion 22, and to indicate the amount of ink remaining in the ink storage chamber 27. The tip 33A of the indicator 33 is formed wider than other portions of the indicator 33.

[0015] The support member 4 has a pin 41 inserted into the through hole 34, and first and second displacement regulating parts 42, 43 provided on both axial sides of the pin 41. The support member 4 is made of synthetic resin. The pin 41 rotatably supports the rotating member 3. The first and second displacement regulating parts 42, 43 have an outer diameter larger than the inner diameter of the through hole 34, and have a shape that cannot be inserted into the through hole 34. As a result, the first and second displacement regulating parts 42, 43 regulate the displacement of the rotating member 3 in the rotation axis direction. The first displacement regulating part 42 and the pin 41 are integrally formed with the frame member 21 and the base member 23 by injection molding. The second displacement regulating part 43 is formed by plastically deforming the tip part 41A of the pin 41, as described later.

[0016] Next, the operation of the rotating member 3 will be described with reference to FIG. 2(a). The ink level L is at the top of the ink storage chamber 27. The rotating member 3 receives a counterclockwise rotation moment M1 due to the buoyancy of the float 32. Since the tip 33A of the display member 33 is in the internal space 26 of the protrusion 22 of the frame member 21, the tip 33A of the display member 33 abuts against the inner wall surface 22B on the left side of the protrusion 22, and the rotating member 3 is prevented from rotating further counterclockwise. That is, the tip 33A of the display member 33 is located at the left end of the internal space 26 of the protrusion 22. The light emitting portion 6A and the light receiving portion 6B of the sensor are provided on both sides of the protrusion 22 in the direction perpendicular to the paper surface, that is, in the front and rear of the area surrounded by the dotted line in FIG. 2(a). When the tip 33A of the display member 33 is in the illustrated position, the light emitted from the light emitting portion 6A is not received by the light receiving portion 6B. As a result, it is detected that the tip 33A of the indicator 33 is in the area enclosed by the dotted line, and it is determined that the remaining amount of ink is equal to or greater than a predetermined amount.

[0017] As the ink is consumed and the ink level L drops to a predetermined position, the top of the float 32 is exposed from the ink, and the exposed portion of the float 32 is no longer subjected to buoyancy. The counterclockwise rotation moment M1 due to the buoyancy applied to the float 32 and the clockwise rotation moment M2 due to the float 32's own weight match, and the force pressing the tip 33A of the display member 33 against the left inner wall surface 22B of the protrusion 22 is lost. When the ink level L drops further, the clockwise rotation moment M2 due to the float 32's own weight exceeds the counterclockwise rotation moment M1 due to the buoyancy applied to the float 32, and the rotating member 3 rotates clockwise. As a result, the buoyancy applied to the float 32 is restored, and the counterclockwise rotation moment M1 and the clockwise rotation moment M2 match. At this time, the tip 33A of the display member 33 is between the left inner wall surface 22B and the right inner wall surface 22C of the protrusion 22, that is, at a position separated from both the inner wall surfaces 22B and 22C. When more ink is consumed, the rotating member 3 rotates clockwise again, and finally, as shown by the broken line, the lower end of the float 32 abuts against the bottom surface of the ink storage chamber 27. The rotating member 3 is prevented from rotating further clockwise, and the tip 33A of the display member 33 stops at a predetermined position between the left inner wall surface 22B and the right inner wall surface 22C of the protrusion 22. The light emitted from the light-emitting portion 6A is received by the light-receiving portion 6B, and the sensor detects that the tip 33A of the display member 33 is on the right side of the internal space 26 of the protrusion 22. As a result, the remaining amount of ink becomes almost zero, and it is determined that the liquid storage container 1A needs to be replaced. In order to improve the accuracy of detecting the position of tip 33A of indicator member 33, it is preferable that tip 33A of indicator member 33 reach the vicinity of inner wall surface 22C on the right side of protrusion 22 when the lower end of float 32 abuts against the bottom surface of ink storage chamber 27. Note that in the above explanation, attention has been focused only on the buoyancy acting on float 32 and the weight of float 32, but in reality, the buoyancy acting on indicator member 33 and the rotational moment due to the weight of indicator member 33 are also taken into consideration. However, as mentioned above, these are not the dominant factors.

[0018] In order for the rotating member 3 to rotate smoothly around the pin 41, the inner diameter of the through hole 34 of the rotating member 3 is made larger than the outer diameter of the pin 41. For this reason, there is a possibility that the rotation axis of the rotating member 3 will be inclined with respect to the central axis of the pin 41. In FIG. 2(d), when the rotating member 3 rotates clockwise R1 and falls toward the first film F1, the through hole 34 of the rotating member 3 will come into contact with the pin 41 at an angle, and the smooth rotation of the rotating member 3 may be impaired. However, when the rotating member 3 falls toward the first film F1, the central connecting portion 31 abuts against the first protrusion 25, and the rotating member 3 is prevented from rotating further in the clockwise direction. Similarly, in FIG. 2(d), when the rotating member 3 rotates counterclockwise R2 and falls toward the second film F2, the second film F2 abuts against the second protrusion 35, and the rotating member 3 is prevented from rotating further in the counterclockwise direction. Meanwhile, gaps G1, G2 are provided between the tip 25A of the first projection 25 and the central connecting portion 31, and between the tip 35A of the second projection 35 and the second film F2. Therefore, the rotating member 3 does not usually come into contact with the first projection 25 or the second film F2. With the above configuration, the rotating member 3 can smoothly rotate around the pin 41. Although not shown in the drawings, the first projection 25 may be formed on the surface of the central connecting portion 31 facing the base member 23.

[0019] Next, a method for manufacturing the liquid storage container 1A will be described with reference to Figs. 2(b) to (d). First, the frame member 21, the base member 23, the rib 24, the first displacement regulating portion 42, and the pin 41 are integrally formed by injection molding. Separately, the rotating member 3 is prepared. As shown in Fig. 2(b), the pin 41 is inserted into the through hole 34 of the central connecting portion 31 of the rotating member 3. The tip portion 41A of the pin 41 is exposed to the outside of the through hole 34. Next, as shown in Fig. 2(c), the exposed tip portion 41A is plastically deformed by heat or pressure using a jig (not shown). The exposed tip portion 41A is compressed in the axial direction and expanded in the radial direction. Next, as shown in Fig. 2(d), the tip portion 41A of the pin 41 is pushed to a predetermined position and further expanded in the radial direction to form the second displacement regulating portion 43. As a result, displacement restriction portions 42, 43 that restrict displacement in the rotation axis direction of the rotating member 3 are formed on both axial sides of the pin 41. Thereafter, the first film F1 and the second film F2 are joined to both side edge portions of the frame member 21, and the ink storage chamber 27 is filled with ink.

[0020] According to this embodiment, the frame member 21, the base member 23, the rib 24, the first displacement regulating portion 42, and the pin 41 are integrally formed, and the second displacement regulating portion 43 is formed by deforming the tip portion 41A of the pin 41. That is, the frame member 21, the base member 23, the rib 24, the first and second displacement regulating portions 42, 43, and the pin 41 are integrally formed (these are called the frame assembly 7). The liquid storage container 1A can be manufactured using only four members, the frame assembly 7, the rotating member 3, and the first and second films F1, F2. Therefore, according to this embodiment, it is possible to provide a liquid storage container 1A with a reduced number of parts. Moreover, since the frame assembly 7 can be manufactured by injection molding of synthetic resin, it can be manufactured at low cost and in a short time.

[0021] Second Embodiment Hereinafter, a liquid storage container 1B according to the second embodiment will be described with reference to FIG. 3. FIG. 3 is a view similar to FIG. 2 showing the first embodiment. Although some of the ribs 24 are omitted in FIG. 3, the ribs 24 can be formed integrally with the frame member 21 as in the first embodiment, thereby achieving the same effect. The second embodiment is similar to the first embodiment except that the supporting method of the rotating member 3 is different. For the configuration and effect omitted, please refer to the description of the first embodiment. The first displacement regulating portion 42 has a shape that cannot be inserted into the through hole 34, and is formed integrally with the pin 41. The second displacement regulating portion is provided as a fixed block 5 having a hole 54 for receiving an end of the pin 41. The fixed block 5 has a disk-shaped first portion 51, a disk-shaped second portion 52 concentric with the first portion 51 and having a hole 54 in the center, and a plurality of legs 53 formed on the edge of the first portion 51. The fixed block 5 is fixed to the base member 23 by joining the legs 53 to the base member 23. The leg 53 is installed so as to avoid the movement range of the float 32. The first film F1 is bonded to the peripheral portion of the frame member 21, the base member 23, and the rib 24, as in the first embodiment. The second film F2 is bonded to the peripheral portion of the frame member 21 and the fixed block 5. The second protrusion 35 is formed on the surface of the first portion 51 of the fixed block 5 facing the rotating member 3. Although not shown, the second protrusion 35 may be formed on the surface of the rotating member 3 facing the first portion 51 of the fixed block 5. In this embodiment, the number of parts is increased compared to the first embodiment, but since one end of the pin 41 is supported by the fixed block 5, the operation of the rotating member 3 becomes smoother. The hole 54 may be omitted, and the pin 41 may be made to abut against the surface of the fixed block 5. Even in this case, the pin 41 is restrained from axial displacement by the fixed block 5.

[0022] The liquid storage container 1B of this embodiment can be manufactured as follows. First, the frame member 21, the first displacement regulating portion 42, and the pin 41 are integrally formed by injection molding. Separately, a rotating member 3 having the same configuration as that of the first embodiment is prepared. Next, as shown in FIG. 3(b), the pin 41 is inserted into the through hole 34 of the central connecting portion 31 of the rotating member 3. The tip portion 41A of the pin 41 is exposed to the outside of the through hole 34. Next, as shown in FIG. 3(c), the fixed block 5 is lowered, and the tip portion 41A of the pin 41 is inserted into the hole 54 of the fixed block 5. The fixed block 5 is also bonded to the base member 23. Next, as shown in FIG. 3(d), the first film F1 and the second film F2 are bonded to both side edges of the frame member 21, and the ink storage chamber 27 is filled with ink.

[0023] (Third embodiment) Hereinafter, a liquid storage container 1C of the third embodiment will be described with reference to FIG. 4. FIG. 4 is a view similar to FIG. 2 showing the first embodiment. Although some of the ribs 24 are omitted in FIG. 4, the ribs 24 can be formed integrally with the frame member 21 as in the first embodiment, thereby achieving the same effect. The third embodiment is similar to the first embodiment except that the configuration of the rotating member 3 is different. Please refer to the description of the first embodiment for the configuration and effect that are omitted. The first displacement regulating portion 42 is formed integrally with the pin 41. The second displacement regulating portion 37 is provided as a part of the rotating member 3, specifically, as the second displacement regulating portion 37 integral with the central connecting portion 31. The central connecting portion 31 is a disk-shaped member similar to the first embodiment. The rotating member 3 is provided with a hole 36 that terminates midway and receives the pin 41. The first displacement regulating portion 42 has a shape that cannot be inserted into the hole 36. The first film F1 is joined to the peripheral portion of the frame member 21, the base member 23, and the rib 24, as in the first embodiment, and the second film F2 is joined to the peripheral portion of the frame member 21, as in the first embodiment. The second displacement regulating portion 37 has a tapered shape in which the cross-sectional area decreases toward the tip portion 37A facing the second film F2, and the tip portion 37A abuts against the second film F2. An example of the tapered shape is a cone, but it may also be a truncated cone, a pyramid, or a truncated pyramid. The axial displacement of the pin 41 of the rotating member 3 is regulated by the first displacement regulating portion 42 and the second displacement regulating portion 37 of the rotating member 3. The axial displacement of the pin 41 of the second displacement regulating portion 37 is regulated by the second film F2. Therefore, the rotating member 3 can rotate without coming off the pin 41. The tapered tip 37A of the rotating member 3 abuts against the second film F2, so that the rotation of the rotating member 3 is not significantly hindered. The first protrusion 25 is provided in the same manner as in the first and second embodiments, but the second protrusion 35 is unnecessary since it is replaced by the second displacement regulating portion 37. This embodiment has the same number of parts as the first embodiment, and furthermore, as the process of deforming the pin 41 is unnecessary as described later, the process can be shortened.

[0024] The liquid storage container 1C of this embodiment can be manufactured as follows. First, the frame member 21, the first displacement regulating portion 42, and the pin 41 are integrally formed by injection molding. Separately, the rotating member 3 is prepared. Next, as shown in FIG. 4(b), the pin 41 is inserted into the hole 36 of the central connecting portion 31 of the rotating member 3. Next, as shown in FIG. 4(c), the pin 41 is inserted all the way into the hole 36 of the rotating member 3. Next, as shown in FIG. 4(d), the first film F1 and the second film F2 are joined to both side edges of the frame member 21, and the ink storage chamber 27 is filled with ink. [Explanation of symbols]

[0025] 1A, 1B, 1C Liquid storage container 2 Container body 3 Rotating parts 4 Support member 32 Float 33 Display material

Claims

1. A container body capable of storing a liquid therein, the container body having a frame portion and a base portion protruding from an inner wall surface of the frame portion; a rotating member that rotates around a rotation axis due to a change in the liquid level of the liquid, the rotating member having a float, a display unit configured to be visible from the outside, and a connection unit that is connected to the float and the display unit and has a hole that coincides with the rotation axis; a support member formed integrally with the base portion and rotatably supporting the rotating member, the support member having a pin inserted into the hole to rotatably support the rotating member, and a displacement restriction portion that restricts displacement of the rotating member in a direction away from the base portion along a rotation axis of the rotating member; A liquid storage container having a

2. A liquid storage container as described in claim 1, wherein the base portion is fixed to the frame portion at multiple positions on the inner wall surface.

3. A liquid storage container as described in claim 1 or 2, wherein the hole is a through hole that penetrates the rotating member, and the displacement regulating portion has a shape that prevents it from being inserted into the through hole and is formed integrally with the pin.

4. A liquid storage container as described in any one of claims 1 to 3, wherein the frame portion includes a first opening and a second opening opposite the first opening on both side surfaces, and further has a first film arranged to cover the first opening and a second film arranged to cover the second opening, the first film being joined to the base portion and the second film being joined to the peripheral portion of the frame portion.

5. A liquid storage container as described in claim 4, wherein a first protrusion is formed on a surface of the base portion facing the rotating member or a surface of the rotating member facing the base portion, and a second protrusion is formed on a surface of the rotating member facing the second film.

6. A liquid storage container as described in claim 4 or 5, having a rib formed integrally with the frame portion or the base portion, and the second film is further joined to the rib.

7. A liquid storage container as described in any one of claims 1 to 6, wherein the display unit extends generally vertically upward from the center of rotation of the rotating member, and the float extends downward from the center of rotation below the display unit.

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