JP2007268793A - Ink cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a delay time until an amount of residual ink is accurately detected, the delay time being caused by a bubble created in an ink tank. <P>SOLUTION: Ink is reserved in the ink tank, and a diffusion face 474 having micro-irregularities formed thereon so as to generate a capillary force is provided to a part of a surface of a sensor arm which is displaced within a prescribed displacement path along with the reduction of the ink reserved in the ink tank. The diffusion face 474 is configured of a reference face 474a and a plurality of projections 474b protruding from the reference face 474a. The reference face 474a is connected to each projection 474b at an angle so as to form a corner 474c. A capillary force generating region formed between the adjacent projections 474b is coupled to another capillary force generating region. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink cartridge that stores ink.

  2. Related Art Inkjet recording apparatuses that perform printing by ejecting ink from nozzles toward recording paper are known. Some of such ink jet recording apparatuses include a removable ink cartridge. When the ink jet head tries to eject ink while the ink in the ink cartridge is empty, not only printing is not performed, but air may enter the ink jet head. If air enters the ink jet head, the head becomes unusable in the worst case. In order to prevent such a situation from occurring, the ink remaining amount in the ink cartridge is always grasped, and when the ink remaining amount in the ink cartridge becomes almost zero, ink ejection from the head is prohibited. It is necessary to control.

Patent Document 1 discloses a technique for detecting the remaining amount of ink in an ink cartridge. In other words, the ink cartridge described in Patent Document 1 includes a sensor arm that is swingably supported in the ink tank. The sensor arm has a detected part at one end and a float part at the other end. When the ink tank is filled with ink, the stopper restricts the rotation of the sensor arm due to the rise in the position along the vertical direction of the float, and the detected part is positioned at the detection position. ing. When the ink level drops below the position of the float in a state where the rotation is restricted by the stopper, the position along the vertical direction of the float descends as the remaining amount of ink decreases. At the same time, the position of the detected part along the vertical direction rises and moves from the detection position to the non-detection position. As a result, when the member to be detected can no longer be detected at the detection position, it is possible to detect a lack of ink.
Japanese Patent Laying-Open No. 2005-125738 (FIG. 1)

  If the ink cartridge vibrates when carrying the ink cartridge or transporting the printer with the ink cartridge mounted, ink bubbles may be generated in the ink tank. When ink bubbles are generated in the ink tank, the rotation of the sensor arm may be hindered by the surface tension of the bubbles adhering to the inner wall surface of the ink tank. In such a case, there is a problem that the ink is detected as being out of ink even though the remaining amount of ink is sufficient. If the bubbles in the ink tank disappear, the sensor arm rotates normally, but until the bubble disappears to the extent that the sensor arm can normally rotate from the state where it was caught by the bubbles, It takes several hours to several tens of hours.

  Accordingly, an object of the present invention is to provide an ink cartridge capable of reducing a time delay until the remaining amount of ink caused by bubbles generated in an ink tank can be accurately detected.

  The ink cartridge of the present invention includes an ink tank that stores ink, a displacement member that is provided in the ink tank and that displaces as the ink stored in the ink tank decreases, and the displacement member has a predetermined displacement. Regulating means for regulating the path so as to displace, and at least one of a part of the inner wall surface of the ink tank corresponding to the displacement path and a part of the surface of the displacement member, A diffusion surface is provided with minute irregularities so as to generate capillary force.

  The bubbles on the diffusion surface disappear faster than the bubbles on the flat surface because the ink constituting the bubbles diffuses on the diffusion surface by capillary force. According to this configuration, even if the displacement of the displacement member is hindered by the surface tension of the bubbles attached to the inner wall surface of the ink tank, it is provided on at least one of the inner wall surface of the ink tank or the surface of the displacement member. Due to the diffusion surface, the bubbles disappear quickly, and the displacement member can be normally displaced. Accordingly, it is possible to reduce the time delay until the remaining amount of ink caused by the bubbles generated in the ink tank can be accurately detected.

  In the ink cartridge of the present invention, the diffusion surface includes a reference surface and a plurality of protrusions protruding with respect to the reference surface, and a capillary force generation region formed between the protrusions adjacent to each other, It is preferable that it is connected to other capillary force generation regions. According to this configuration, the ink drawn into the capillary force generation region can be smoothly diffused. Therefore, it is possible to further shorten the time required until the bubbles disappear to such an extent that the displacement member is normally displaced.

  In the ink cartridge of the present invention, it is preferable that the reference surface and the protruding portion are connected at an angle so as to have a corner. According to this configuration, it is possible to eliminate the bubbles more reliably on the diffusion surface.

  In the ink cartridge of the present invention, the ink tank protrudes from the main body portion and has a width narrower than the width of the main body portion, and a space communicating with the inside of the main body portion is provided inside. The displacement member has a plate-like detected portion that is displaced in the space of the detection portion by the restriction of the restriction means, and the diffusion surface is the covered portion. It may be formed on the surface of the detection unit.

  According to this configuration, since the detection unit protrudes from the main body, it can be easily accessed from the outside of the ink cartridge, and the width of the detection unit is narrower than the width of the main body, so that an inexpensive translucent sensor can be used to cover the displacement member. The detection unit can be detected. Air bubbles are likely to stay in the space in the detection unit that protrudes from the main body and has a width narrower than that of the main body, but a diffusion surface is formed in the detected portion that displaces the space in the detection unit. Malfunctioning due to air bubbles is avoided. Accordingly, it is possible to effectively reduce the time delay until the remaining amount of ink due to the bubbles generated in the ink tank can be accurately detected.

  In the ink cartridge of the present invention, the detection unit is provided at a position sandwiched between the light emitting unit and the light receiving unit of the transmission optical sensor provided in the ink jet recording apparatus when mounted on the ink jet recording apparatus. Also good. According to this configuration, the detected portion can be accurately detected with a simple mechanism.

  In the ink cartridge of the present invention, the displacement member has the detected portion at one end and a float portion having a specific gravity smaller than that of the ink stored in the ink tank at the other end. The restricting means includes a support mechanism that pivotally supports between the detection portion and the float portion so that the displacement member can swing, and a restricting portion that restricts the swing range of the displacement member. It is preferable.

  When the end of the oscillating displacement member comes into contact with bubbles attached to the inner wall surface of the ink tank, a large moment force acts in a direction that prevents the oscillation with a relatively small surface tension. According to this configuration, the detected part is located at the end of the displacement member. Therefore, the diffusing surface formed in the detected part can quickly eliminate the bubbles attached to the detected part, and the displacement member can be normally swung more quickly.

  In the ink cartridge according to the aspect of the invention, the displacement member includes the detected portion and a float portion having a specific gravity smaller than that of the ink stored in the ink tank, and the restricting unit is disposed on the ink tank. You may have the wall part extended in the displacement direction of the ink liquid level accompanying the reduction | decrease of the stored ink. According to this configuration, compared to the type in which the displacement member swings, the region in which the displacement member is displaced is narrowed, so the degree of freedom in designing the ink cartridge is increased.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing an appearance of an ink cartridge 1 according to the present embodiment, and FIG. 2 is an exploded perspective view of the ink cartridge 1.

  As shown in FIGS. 1 and 2, the ink cartridge 1 includes a case 200 that covers substantially the entire ink reservoir 100 that stores ink, and the ink cartridge 1 that is attached to the case 200 when the ink cartridge 1 is transported. The protector 300 which protects 100 is provided. In the present embodiment, the ink reservoir 100, the case 200, and the protector 300 are made of a resin material and do not have a metal material, and therefore can be incinerated at the time of disposal. Examples of the resin material include nylon, polyethylene, and polypropylene.

  As shown in FIG. 1, the ink cartridge 1 is configured as a substantially hexahedron. That is, it is composed of approximately six surfaces including a pair of substantially rectangular surfaces having a maximum area and side surfaces located in four directions connecting the pair of surfaces. In the following description, the direction along the long side of the pair of substantially rectangular surfaces that is the largest area of the hexahedron is the longitudinal direction, the direction along the short side of the surface is the short direction, and the direction connecting the pair of surfaces ( The direction perpendicular to the longitudinal direction and the short direction) is referred to as the width direction. Moreover, a pair of substantially rectangular surfaces which become the largest area of a hexahedron are called a front surface and a back surface.

  Next, the ink reservoir 100 will be described in detail with reference to FIG. FIG. 3 is a view showing the ink reservoir 100. As shown in FIG. 3, the ink reservoir 100 includes an ink tank 110 that stores ink and an ink supply unit that supplies the ink stored in the ink tank 110 to the outside (the ink jet recording apparatus 1000 (see FIG. 7)). 120, an air introduction unit 130 that introduces air into the ink tank 110, and an ink dispensing unit 150 that dispenses ink into the ink tank 110.

  Note that the state of the ink reservoir 100 shown in FIG. 3 is a posture in which the ink cartridge 1 is mounted on the ink jet recording apparatus 1000 (see FIG. 7). That is, the ink cartridge 1 is mounted in such a posture that the surface having the maximum area is vertical and the long side of the surface having the maximum area is along the horizontal direction. At this time, the ink supply unit 120 and the air introduction unit 130 are Located on the side. More specifically, the ink supply unit 120 is located on the bottom side, and the air introduction unit 130 is located on the ceiling side. In the following description, the vertical direction is defined with the top side in the mounting posture of the ink cartridge 1 to the ink jet recording apparatus 1000 being “upper” and the bottom side being “lower”. In other words, the displacement direction of the ink liquid level accompanying the decrease in the ink stored in the ink reservoir 100 is the vertical direction.

  The ink tank 110 protrudes from the main body 170 in the longitudinal direction between the main body 170, the ink supply unit 120, and the air introduction unit 130, and detects that a space communicating with the main body 170 is formed therein. Part 140. That is, the ink supply unit 120, the air introduction unit 130, and the detection unit 140 are provided on the same wall surface of the ink reservoir 100. In addition, a sensor arm 470 that can be swung around a lower left portion in FIG. 3, that is, near the ink supply unit 120 as a fulcrum, is disposed in the ink tank 110 as the ink stored in the ink tank 110 decreases. ing.

  Here, the sensor arm 470 will be described with reference to FIG. FIG. 5A is a diagram showing the front side of the sensor arm 470, and FIG. 5B is a diagram showing the sensor arm 470 as viewed in the direction of arrow Vb in FIG. 5A. The sensor arm 470 is a member for detecting the remaining amount of ink in the ink tank 110. The sensor arm 470 is made of a resin material (for example, styrene resin) having a specific gravity smaller than that of ink, and is manufactured by injection molding.

  The sensor arm 470 is a swinging member that is pivotally supported in the ink tank 110 and swings according to the remaining amount of ink, and is a substantially C-shaped arm holding portion 425 (see FIG. 3) provided in the main body 170. 5), a float portion 471 located on the right side of the attachment portion 472 in FIG. 5A, and a substantially vertical direction from the attachment portion 472 to the float portion 471 (FIG. 5). And (a) an arm portion 473 extending upward and inclined further upward. The volume of the float part 471 is sufficiently larger than the volume of the arm part 473. The end portion of the arm portion 473 is a detected portion 473a that is detected by a remaining ink amount detection sensor 1014 (see FIG. 7) provided in the inkjet recording apparatus 1000. The detected portion 473a has a plate shape having a surface parallel to the paper surface of FIG. In the state where the sensor arm 470 is attached in the ink tank 110, the detected portion 473a of the sensor arm 470 is disposed in a space in the detection portion 140 as shown in FIG.

  That is, the sensor arm 470 has a detected portion 473a at one end (the left end portion in FIG. 5A) and a float portion 471 at the other end (the right end portion in FIG. 5A). It can swing around the mounting portion 472. Here, as shown in FIG. 5A, the length from the mounting portion 472, which is the center of rotation, to the detected portion 473a is longer than the length from the mounting portion 472 to the end of the float portion 471. The sensor arm 470 is restricted from rotating clockwise in FIG. 3 when the float portion 471 contacts the bottom wall of the ink tank 110. Further, when the detected portion 473a comes into contact with a stopper 142 described later, the counterclockwise rotation in FIG. 3 is restricted. As described above, the swing range of the sensor arm 470 is regulated so as to swing along the fixed swing path by the bottom wall of the ink tank 110 and the stopper 142 described later.

  The arm portion 473 is formed with ribs 473b that protrude in the width direction (left-right direction in FIG. 5B) to maintain strength. The to-be-detected part 473a is provided with substantially hemispherical arm protrusions 473c and 473d at two locations (upper and lower ends in FIG. 5A). Since the arm protrusions 473c and 473d are formed in a hemispherical shape, only the tip of the arm protrusions 473c and 473d is in contact with the inner wall of the detection unit 140, thereby suppressing the influence of the surface tension of the ink. it can.

  The sensor arm 470 is made of a resin material having a specific gravity smaller than that of ink. Further, the volume of the float portion 471 is sufficiently larger than the volume of the arm portion 473. More specifically, the volume ratio between the arm portion 473 and the float portion 471 is the same as that shown in FIG. 5A that occurs in the sensor arm 470 due to gravity and buoyancy when the float portion 471 is located in the ink liquid. When the clockwise moment becomes larger than the clockwise moment and a part of the float portion 471 is exposed from the ink liquid, the buoyancy generated in the float portion 471 decreases, and the counterclockwise moment and the clockwise moment The moment is set to be equal. Accordingly, after a part of the float part 471 is exposed from the ink liquid, when the ink level further decreases as the ink decreases, the float part 471 moves downward following the liquid level. When the float portion 471 moves downward, the arm portion 473 moves upward using the attachment shaft 472a of the attachment portion 472 as a support shaft.

  Further, as shown in FIG. 5A, a diffusion surface in which minute irregularities are provided on the surface of the sensor arm 470, more specifically, a part of the float part 471 and a part of the arm part 473 excluding the rib 473b. 474 is formed. Here, the diffusion surface 474 will be described with reference to FIG. 6A is an enlarged view of the detected portion 473a, and FIG. 6B is a cross-sectional view taken along the line VIb-VIb in FIG. In FIG. 6 (a), the concave portions are hatched for the sake of explanation. Moreover, in FIG.6 (b), the up-down direction is expanded and drawn.

  As shown in FIG. 6, the diffusing surface 474 includes a reference surface 474a (shaded portion in FIG. 6A) and a plurality of protruding portions 474b protruding with respect to the reference surface 474a. As shown in FIG. 6B, the reference surface 474a and the side surface of the protruding portion 474b are not connected by a smooth curved surface but are connected at an angle so that a corner portion 474c is formed. Accordingly, the corner portion 474c (the connection portion between the reference surface 474a and the side surface of the protruding portion 474b) has a structure that generates a strong capillary force. Here, as shown in FIG. 6A, the shape of the plurality of protrusions 474b when viewed from the direction orthogonal to the diffusing surface 474 is not uniform and various, but all of them are substantially circular. is there. The sizes of the plurality of protrusions 474b when viewed from the direction orthogonal to the diffusing surface 474 are also varied in size. Furthermore, as shown in FIG. 6B, the lengths from the reference surface 474a to the tips of the plurality of protrusions 474b are not uniform and vary.

  In the present embodiment, the angle θ formed by the reference surface 474a and the protrusion 474b is about 90 degrees, and the length from the reference surface 474a of the diffusion surface 474 to the tip of the protrusion 474b (difference in height of the unevenness). t1 is 0.04 to 0.06 mm, the average diameter of the protrusions 474b is 0.8 mm, and the area ratio between the reference surface 474a and the protrusions 474b is 0.5.

  Further, the gap between the adjacent projecting portions 474b is long enough to generate a capillary force against the ink when ink is present in the gap, specifically, about 0.4 mm. Therefore, a capillary force generation region is formed between the protrusions 474b adjacent to each other. And the capillary force generation area | region between a certain two protrusion part 474b is connected with the other capillary force generation | occurrence | production area | region. Therefore, the liquid on the diffusion surface 474 diffuses to other regions by the capillary force generated in the capillary force generation region where the liquid is located.

  Returning to FIG. 3, the main body 170 includes a frame portion 180 having edges on the front and back sides of the main body 170, and a film 160 that is welded to the front and back edges of the frame portion 180. Have. That is, in the present embodiment, a space for storing ink is formed inside the main body 170 by closing both the front side and the back side of the frame unit 180 with the film 160. Therefore, the thickness of the ink reservoir 100 can be reduced as compared with the case where both sides are closed by the side walls.

  The frame portion 180 has a surface parallel to the width direction of the ink tank 110, and the outer peripheral weld portion 400 that is a standing wall that defines the internal space of the main body portion 170 and a surface parallel to the width direction of the ink tank 110. The inner welded portions 411 to 417 arranged on the inner side of the outer peripheral welded portion 400, and a surface orthogonal to the width direction of the ink tank 110. The outer peripheral welded portion 400 and the inner welded portions 411 to 417 are provided. Connecting portions 420, 430, and 440 are provided. In more detail, the connection part 420 has connected the outer periphery welding part 400 and the internal welding part 411 in the lower left part of FIG. The connection part 430 connects the outer periphery weld part 400 and the internal weld part 412 in the upper part of FIG. The connecting part 440 connects the outer periphery welded part 400 and the inner welded parts 413 to 417 from the upper left part to the lower right part of FIG. Here, in FIG. 3, black portions of the outer periphery welded portion 400 and the inner welded portions 411 to 417 are located on the same virtual plane, and the film 160 is welded to the portions by ultrasonic welding. In addition, the connecting portion 420 is provided with an arm holding portion 425 that holds the mounting portion 472 of the sensor arm 470.

  As shown in FIG. 3, the inner welded portions 411 to 417 have at least some of the standing walls inclined downward or substantially perpendicular to the longitudinal direction of the frame portion 180, that is, the lower side of the ink cartridge 1. , And the lower end thereof is not connected to the outer periphery welded portion 400. Therefore, in order to suppress the slackness of the film 160 when the film 160 is welded to the frame portion 180, even if the plurality of internal weld portions 411 to 417 are provided inside the outer periphery weld portion 400, the plurality of internal weld portions 411 are provided. ˜417 can reduce the blockage of ink flow. Further, since the inner welded portions 411 to 417 are arranged to be diffused inside the outer peripheral welded portion 400, it is possible to reduce the occurrence of slack in the film 160 and to effectively reduce the hindrance to the ink flow. it can.

  Next, the structure of the detection unit 140 will be described with reference to FIG. 4A is a diagram showing an outline of the vicinity of the detection unit 140, and FIG. 4B is a cross-sectional view of the detection unit 140 taken along line IVb-IVb in FIG. 4A. (C) is sectional drawing of the detection part 140 vicinity which follows the IVc-IVc line | wire of Fig.4 (a).

  As shown in FIG. 4 (a), the detection unit 140 projects outward (leftward in FIG. 4 (a)) from the main body 170, and as shown in FIGS. 4 (b) and 4 (c), A space that communicates with the inside of the main body 170 and extends in the vertical direction is formed inside. And in the space in the detection part 140, the to-be-detected part 473a provided in the end of the sensor arm 470 is arrange | positioned. It should be noted that the detected portion 473a can be displaced in the vertical direction within the detecting portion 140. In addition, a stopper 142 that supports the sensor arm 470 from below and restricts the displacement of the sensor arm 470 is provided inside the detection unit 140.

  Here, the detection unit 140 has translucency, and when the ink cartridge 1 is attached to the ink jet recording apparatus 1000, the light emission of the transmissive ink remaining amount detection sensor 1014 provided in the ink jet recording apparatus 1000 is achieved. It is provided at a position sandwiched between the portion 1014a and the light receiving portion 1014b (see FIG. 7). The sensor arm 470 has a light shielding property. Accordingly, as described above, the remaining ink level detection sensor 1014 moves the arm portion 473 upward in accordance with the rotation of the sensor arm 470 when the ink level decreases due to the decrease in ink, and the detected target is detected. When the part 473a moves upward in the detection part 140, the displacement of the detected part 473a can be detected. Therefore, the ink remaining amount detection sensor 1014 can detect that the ink remaining amount has decreased.

  As shown in FIG. 4B, the length t <b> 2 along the width direction of the detection unit 140 is shorter than the length t <b> 3 along the width direction of the main body 170. Therefore, since the interval between the light emitting unit 1014a and the light receiving unit 1014b (see FIG. 7) of the ink remaining amount detection sensor 1014 can be relatively narrow, the detected unit 473a can be reliably secured even with an inexpensive sensor. Can be detected.

  Returning to FIG. 3, the ink supply unit 120 communicates with the ink tank 110 and has a cylindrical ink supply path 121 extending in the longitudinal direction, and an ink supply mechanism in which a part thereof is inserted into the ink supply path 121. 122. In the state where the ink cartridge 1 is not attached to the ink jet recording apparatus 1000, the ink supply mechanism 122 closes the ink flow path, is attached to the ink jet recording apparatus 1000, and the ink extraction tube 1015 of the ink jet recording apparatus 1000 (FIG. 7). When (see) is inserted, the ink flow path is opened. Accordingly, the ink supply unit 120 can supply the ink in the ink tank 110 to the ink jet recording apparatus 1000 when the ink cartridge 1 is mounted on the ink jet recording apparatus 1000.

  The air introduction part 130 communicates with the ink tank 110 and extends in the longitudinal direction, and a cylindrical air communication path 131, a part of which is inserted into the air communication path 131 and outside the air communication path 131. And an air introduction mechanism 132 having a rod-shaped valve opening 132a projecting toward the surface. In the state where the ink cartridge 1 is not attached to the ink jet recording apparatus 1000, the air introduction mechanism 132 closes the air flow path and is attached to the ink jet recording apparatus 1000, and the valve opening portion 132 a is the attachment surface of the ink jet recording apparatus 1000. 1013 (see FIG. 7), and when pressed toward the atmosphere communication path 131, the atmospheric flow path is opened. Therefore, the atmosphere introduction unit 130 can communicate the inside of the ink tank 110 with the atmosphere when the ink cartridge 1 is attached to the inkjet recording apparatus 1000.

  The ink dispensing unit 150 is provided in the vicinity of the bottom of the side surface of the ink reservoir 100 opposite to the side surface where the ink supply unit 120 and the air introduction unit 130 are provided, and the dispensing tube unit extends in the longitudinal direction. 151 and an ink dispensing plug (not shown) press-fitted into the dispensing cylinder portion 151. The dispensing tube portion 151 has a communication hole (not shown) that allows the dispensing tube portion 151 and the ink tank 110 to communicate with each other. The ink dispensing plug is made of an elastic member such as pulch rubber, and once it is press-fitted into the dispensing cylinder 151, it cannot be easily removed, and the needle entry path is blocked even if the needle is inserted or removed. It is configured to be.

  Here, a method for detecting the remaining amount of ink in the ink tank 110 will be described with reference to FIG. FIG. 8A shows a state where there is a remaining amount of ink, and FIG. 8B shows a state where there is no remaining amount of ink.

  As shown in FIG. 8A, a state where a large amount of ink is stored in the ink tank 110 (at least above the position of the float portion 471 when the detected portion 473a is in contact with the stopper 142) In the state where the liquid level is located), as described above, the counterclockwise moment generated in the sensor arm 470 is larger than the clockwise moment, so that the float portion 471 is floating in the ink. At this time, the detected portion 473a of the sensor arm 470 is located at a detection position that blocks between the light emitting portion 1014a and the light receiving portion 1014b of the ink remaining amount detecting sensor 1014. This state is a state with ink, and the presence of ink is determined by a control board (not shown) of the inkjet recording apparatus 1000.

  Thereafter, when the ink in the ink tank 110 decreases and the arm part 473 is exposed from the ink surface, the buoyancy generated in the arm part 473 decreases. Thus, the clockwise moment generated in the sensor arm 470 is reduced, but the counterclockwise moment is still larger than the clockwise moment, and the sensor arm 470 remains at the position shown in FIG. ing. When the ink further decreases and the float portion 471 is exposed from the ink surface, the buoyancy generated in the arm portion 473 decreases. Thereby, the counterclockwise moment generated in the sensor arm 470 is reduced. When a part of the float portion 471 is exposed from the ink liquid, the counterclockwise moment and the clockwise moment become equal. Thereafter, when the ink further decreases, the float portion 471 moves downward following the ink level that decreases. Then, when the ink in the ink tank 110 is almost exhausted and disappears from the bottom surface of the ink tank 110, the float portion 471 of the sensor arm 470 comes into contact with the bottom surface. Due to the downward movement of the float portion 471, the sensor arm 470 rotates clockwise about the attachment portion 472, and the detected portion 473a of the sensor arm 470 is displaced upward. When the detected portion 473a is displaced to a non-detection position that does not block between the light emitting portion 1014a and the light receiving portion 1014b of the ink remaining amount detecting sensor 1014, light passes between the light emitting portion 1014a and the light receiving portion 1014b. This state is a state without ink, and it is determined that there is no ink on a control board (not shown) of the ink jet recording apparatus 1000.

  Next, the case 200 will be described. As shown in FIG. 2, the case 200 includes a first case member 210 and a second case member 220 that sandwich the ink reservoir 100 from the width direction. The first case member 210 is a member that covers the lower side surface of the ink reservoir 100 in FIG. 2, and the second case member 220 is a member that covers the upper side surface of the ink reservoir 100 in FIG. 2. The first and second case members 210 and 220 are made of a resin material and are manufactured by injection molding.

  The first case member 210 and the second case member 220 are formed in substantially the same shape, and in a state where the ink reservoir 100 is sandwiched, a substantially circular through hole that exposes a part of the ink supply unit 120 to the outside is formed. The remaining ink detection sensor includes the case notches 211 and 221 constituting the case, the case notches 212 and 222 constituting a substantially circular through-hole exposing a part of the air introduction part 130 to the outside, and the side wall of the detection part 140. Case notches 213 and 223 are formed, which form through holes into which 1014 (see FIG. 7) can be inserted to the position where the detection unit 140 is sandwiched, on both sides of the detection unit 140 (upper and lower sides in FIG. 2).

  Next, the outer shape of the case 200 will be described. A concave step with respect to the surfaces of the first and second case members 210 and 220 is formed at both ends in the short direction of the first and second case members 210 and 220 so as to extend in the longitudinal direction. At the stepped portion, the first and second case members 210 and 220 are welded, and the ink reservoir 100 is fixed to the case 200. As for the stepped portion, the stepped portion on the ink supply unit 120 side (right front side in FIG. 2) is the first case welded portion 216, 226, and the stepped portion on the atmosphere introducing unit 130 side (left port side in FIG. 2) is the second case. It is the welding part 217,227. An engaging portion 226a extending in the lateral direction is formed at the end of the second case member 220 opposite to the side where the case notch 221 is formed of the first case welded portion 226. Although not shown, the first case member 220 is also formed with an engaging portion similar to the engaging portion 226a. The second case welded portions 217 and 227 have locking portions 217 a and 227 a formed in a concave shape at a substantially intermediate position in the longitudinal direction of the case 200.

  The protector 300 is a member that covers the surface of the ink reservoir 100 on which the ink supply unit 120 and the air introduction unit 130 are provided. When the ink cartridge 1 is shipped, the protector 300 is configured to remove the ink supply unit 120 and the air introduction unit 130. It is a member for protection. The protector 300 is made of a resin material and is manufactured by injection molding. As shown in FIG. 2, the protector 300 has a protector through-hole 310 formed at a location corresponding to the atmosphere introduction part 130 side (the port side of FIG. 2), so that the valve opening part 132 a of the atmosphere introduction mechanism 132 is provided. Can be protected.

  Next, the mounting of the ink cartridge 1 to the ink jet recording apparatus 1000 will be described with reference to FIG. When the ink cartridge 1 is attached to the ink jet recording apparatus 1000, the protector 300 is removed from the case 200.

  As shown in FIG. 7, when the ink cartridge 1 is mounted on the mounting unit 1010 on the ink jet recording apparatus 1000 side, the surface from the mounting surface 1013 facing the ink supply unit 120 and the air introduction unit 130 of the ink cartridge 1 Projecting in a direction perpendicular to the right direction (FIG. 7 right direction), supporting the locking rod 1011 locked to the locking portions 217a and 227a of the case 200, and the first case welded portions 216 and 226 of the case 200 from below, And a support portion 1012 formed in a concave shape in accordance with the shape of the first case welded portions 216 and 226. The locking rod 1011 has a convex portion 1011a that protrudes toward the support portion 1012 and is formed in substantially the same shape as the locking portions 217a and 227a.

  An ink remaining amount detection sensor 1014 is disposed on the mounting surface 1013 of the mounting unit 1010. The ink remaining amount detection sensor 1014 is formed in a substantially U-shape, and one open end of the U-shape is a light emitting unit 1014a that emits light, and the other end receives light. Part 1014b. The light emitting portion 1014a and the light receiving portion 1014b are attached so as to protrude from the mounting surface 1013 so as to be inserted through the through holes formed by the case cutout portions 213 and 223 and the detection portion 140, respectively. The ink remaining amount detection sensor 1014 does not output a signal to a control board (not shown) provided in the inkjet recording apparatus 1000 when the light receiving unit 1014b receives the light emitted from the light emitting unit 1014a. (Or output) When the light emitted from the light emitting unit 1014a is blocked and the light receiving unit 1014b cannot receive light, a signal is output (or not output) to the control board.

  In addition, an ink extraction tube 1015 is provided on the side corresponding to the ink supply unit 120 of the mounting surface 1013 (the lower side in FIG. 7A), while the side corresponding to the air introduction unit 130 of the mounting surface 1013 ( In FIG. 7A, the mounting surface 1013 is flat. An ink flow path 1013a is connected to the ink extraction tube 1015, and ink is supplied to an ejection port (not shown) through the ink flow path 1013a. In addition, an atmosphere introduction path 1013b is formed on the mounting surface 1013 on the atmosphere introduction unit 130 side, and the atmosphere is introduced into the ink cartridge 1 (ink tank 110) through the atmosphere introduction path 1013b.

  Further, the mounting portion 1010 is engaged with the engaging portions 216a and 226a of the case 200 on the tip side of the support portion 1012 (the right side in FIG. 7A, the end portion on the ink cartridge 1 side) and rotates. A joint member 1017 is provided. The engagement member 1017 includes an engagement end portion 1017a that engages with the engagement portions 216a and 226a of the case 200, a shaft support portion 1017b that is connected to the engagement end portion 1017a and supports the engagement member 1017, and a shaft support portion. 1017b and a covering portion 1017c that covers the opposite side of the surface of the case 200 that faces the mounting portion 1010.

  The ink cartridge 1 is inserted by inserting the first case welded portions 216 and 226 of the case 200 so as to contact the support portion 1012 and pressing the first case welded portions 216 and 226 to slide on the support portion 1012. Done in That is, as shown in FIG. 7A, the ink cartridge 1 is slid in the direction of arrow E.

  As shown in FIG. 7B, when the ink cartridge 1 is pushed in the mounting portion 1010 direction (leftward in FIG. 7B), the locking rod 1011 is pushed by the second case welding portions 217 and 227. , Elastic deformation in a direction away from the support portion 1012. Further, the engagement end portion 1017a of the engagement member 1017 comes into contact with the engagement portions 216a and 226a. Further, when the ink cartridge 1 is pushed in, the engaging member 1017 rotates upward (in the direction of arrow F in FIG. 7B).

  As shown in FIG. 7C, when the ink cartridge 1 is further pushed in from the state of FIG. 7B (or when the user rotates the engaging member 1017 in the direction of arrow F in FIG. 7B). The convex portion 1011a of the locking rod 1011 is fitted and engaged with the locking portions 217a and 227a of the case 200, and the ink cartridge 1 is fixed. Therefore, the ink cartridge 1 is prevented from being easily detached due to printing vibration or the like in the state where the ink cartridge 1 is mounted on the mounting unit 1010.

  Further, when the ink cartridge 1 is attached to the attachment portion 1010, the ink extraction tube 1015 is inserted into the ink supply portion 120 so that ink can be supplied, and the valve opening portion 132a of the air introduction portion 130 is attached to the attachment surface 1013. The ink remaining amount detection sensor 1014 is inserted into the through hole formed by the case notches 213 and 223 and the detection unit 140, and the ink remaining amount can be detected. .

  As described above, in the ink cartridge 1 of the present embodiment, the sensor arm 470 that displaces a certain displacement path in the ink tank 110 in which ink is stored as the ink stored in the ink tank 110 decreases. Is provided. A diffusion surface 474 having minute irregularities is formed on a part of the surface of the sensor arm 470 so that capillary force is generated. When bubbles adhere to the diffusion surface 474, the ink constituting the bubbles diffuses onto the diffusion surface 474 by capillary force, and thus disappears more rapidly than bubbles attached to a flat surface. Therefore, the ink cartridge 1 according to the present embodiment generates ink bubbles in the ink tank 110 when the ink cartridge 1 is carried or when the ink jet recording apparatus 1000 is carried with the ink cartridge 1 mounted. Even when the displacement of the sensor arm 470 is hindered by the surface tension of the bubbles adhering to the inner wall surface of the ink tank 110, the bubbles disappear quickly due to the diffusion surface 474 provided on the surface of the sensor arm 470. The sensor arm 470 can be displaced normally. Therefore, it is possible to reduce the time delay until the remaining amount of ink caused by the bubbles generated in the ink tank 110 can be accurately detected.

  Further, in the ink cartridge 1 of the present embodiment, the diffusion surface 474 includes a reference surface 474a and a plurality of protrusions 474b protruding with respect to the reference surface 474a, and is formed between the adjacent protrusions 474b. The generated capillary force generation region is connected to other capillary force generation regions. Therefore, the ink drawn into the capillary force generation region can be smoothly diffused. Therefore, it is possible to further reduce the time required until the bubbles disappear to such an extent that the sensor arm 470 is normally displaced.

  In the diffusing surface 474 of the ink cartridge 1 of the present embodiment, the reference surface 474a and the protruding portion 474b are connected at an angle so that a corner portion 474c is formed. Therefore, compared to a shape in which the reference surface 474a and the protruding portion 474b are continuous with a smooth curved surface, a stronger capillary force can be generated by the corner portion 474c, and bubbles can be more reliably eliminated at the diffusion surface 474. .

  Furthermore, in the ink cartridge 1 of the present embodiment, the ink tank 110 has a width narrower than the width of the main body 170 while projecting from the main body 170 and the main body 170 in the longitudinal direction, and vertically in the interior. And a detection unit 140 in which a space communicating with the main body unit 170 is formed. Then, by attaching the sensor arm 470 to the arm holding portion 425, the displacement of the sensor arm 470 is regulated so that the plate-like detected portion 473a is displaced in the space inside the detecting portion 140. A diffusion surface 474 is formed on a part of the float part 471 of the sensor arm 470 and a part of the arm part 473 excluding the rib 473b. Therefore, since the detection unit 140 protrudes from the main body 170, it can be easily accessed from the outside of the ink cartridge 1 (specifically, the ink jet recording apparatus 1000), and the width of the detection unit 140 is narrower than the width of the main body 170. Therefore, the detected portion 473a of the sensor arm 470 can be detected with an inexpensive translucent sensor. Air bubbles are likely to stay in the space in the detection unit 140 that protrudes from the main body unit 170 and has a narrower width than the main body unit 170, but the diffused surface of the detected unit 473a that displaces the space in the detection unit 140 Since 474 is formed, malfunction due to bubbles is avoided. Therefore, it is possible to effectively reduce the time delay until the remaining amount of ink caused by the bubbles generated in the ink tank 110 can be accurately detected.

  In addition, in the ink cartridge 1 of the present embodiment, the detection unit 140 includes a transmissive ink remaining amount detection sensor 1014 provided in the ink jet recording apparatus 1000 when the ink cartridge 1 is attached to the ink jet recording apparatus 1000. The light emitting unit 1014a and the light receiving unit 1014b are provided at positions sandwiched between the light emitting unit 1014a and the light receiving unit 1014b. Therefore, the detected portion 473a can be reliably detected with a simple mechanism.

  Further, in the ink cartridge 1 according to the embodiment of the present invention, the sensor arm 470 includes the detected portion 473a at one end and the float portion 471 having a specific gravity smaller than that of the ink at the other end. The mounting portion 472 located between the 473a and the float portion 471 is swingable. The swing range of the sensor arm 470 includes an arm holding portion 425 that pivotally supports the sensor arm 470 and the bottom of the ink tank 110 that contacts the float portion 471 when the sensor arm 470 rotates clockwise in FIG. When the sensor arm 470 rotates counterclockwise in FIG. 3, the wall is restricted by a stopper 142 that comes into contact with the detected portion 473a so as to be displaced along a certain displacement path. When the end of the sensor arm 470 comes into contact with bubbles attached to the inner wall surface of the ink tank 110, a large moment force acts in a direction that prevents the oscillation with a relatively small surface tension. In the ink cartridge 1 of the present embodiment, the diffusion surface 474 is formed in the detected portion 473a provided at one end of the sensor arm 470. Therefore, the bubbles adhering to the detected portion 473a can be quickly eliminated, and the sensor arm 470 can be normally swung more quickly.

  Next, a second embodiment of the present invention will be described with reference to FIG. The configuration of the ink cartridge according to the second embodiment is mainly different from the configuration of the ink cartridge 1 according to the first embodiment. In the ink cartridge 1, the ink remaining amount detection sensor 1014 of the ink jet recording apparatus 1000 is used. The detected portion 473a detected by the sensor is provided at one end of the sensor arm 470 that rotates as the ink in the ink tank 110 decreases. However, in the ink cartridge 500 of the present embodiment, the detected portion 573 is detected. Is provided on a displacement member 570 that is displaced along the displacement direction of the ink liquid level as the ink in the ink tank 510 decreases.

  FIG. 9 is a cross-sectional view of the ink cartridge 500 of the present embodiment, and shows a state in which the ink cartridge 500 is mounted. As shown in FIG. 9, the ink cartridge 500 of the present embodiment is provided on an ink tank 510 that stores ink, and one wall (bottom wall) of the ink tank 510, and is stored in the ink tank 510. An ink supply unit 520 that supplies ink to the outside, an ink dispensing unit 550 that dispenses ink into the ink tank 510, and a cap 530 that covers the wall of the ink tank 510 where the ink supply unit 520 is provided from the outside. It is mainly equipped with. The vertical direction on the paper surface of FIG. 9 is the vertical direction of the ink cartridge 500, and the direction perpendicular to the paper surface is the width direction of the ink cartridge 500.

  The ink tank 510 is translucent and has a bottomed box-shaped main body 511 having an opening at the top, and a lid 515 that is welded to the main body 511 and closes the opening of the main body 511. A displacement member 570 having a light shielding property is disposed inside. The displacement member 570 is formed of a material having a specific gravity smaller than the specific gravity of the ink, and includes a float portion 571, a connection portion 572 that extends vertically upward from the float portion 571 in FIG. It has a detected part 573 formed at the end opposite to the float part 571 of 572. Further, the volume ratio of the float portion 571 in the displacement member 570 is such that when the float portion 571 is located in the ink liquid, the buoyancy generated in the displacement member 570 is larger than the gravity, and the float portion 571 When the portion is exposed from the ink liquid (when the ink liquid level is lower than the line A shown in FIG. 9), the buoyancy generated in the displacement member 570 is set to be equal to the gravity. The width of the float portion 571 is wider than the width of a space formed in a detection portion 540 described later, and the width of the connection portion 572 and the detected portion 573 is larger than the width of a space formed in the detection portion 540. Is also narrow. A diffusion surface 574 similar to the diffusion surface 474 formed on the surface of the sensor arm 470 of the first embodiment is formed over the entire surface of the displacement member 570.

  A detection unit 540 is provided on the side surface (left side surface in FIG. 9) of the main body 511 so as to protrude from the main body 511. The detection unit 540 has a width that is narrower than the width of the ink cartridge 500. Inside the detection unit 540, a space that extends in the vertical direction (the displacement direction of the ink liquid level accompanying the decrease in the ink stored in the ink tank 510) and communicates with the ink tank 510 is formed. The detection unit 540 is sandwiched between the light emitting unit 2014 a and the light receiving unit 2014 b of the transmissive ink remaining amount detection sensor 2014 provided in the ink jet recording apparatus 2000 when the ink cartridge 500 is attached to the ink jet recording apparatus 2000. It is. In addition, a restriction wall 512 extending upward is provided on the bottom surface of the ink tank 510 in the vicinity of the detection unit 540. More specifically, the regulation wall 512 is provided at a position facing the space in the detection unit 540 in the ink tank 510. The displacement member 570 is disposed such that the float portion 571 is located between the detection portion 540 and the restriction wall 512 and the detected portion 573 is located within the detection portion 540. Therefore, the displacement path of the displacement member 570 is restricted in the vertical direction by the restriction wall 512.

  The lid 515 is formed with a regulation projection 516 that projects (downward) into the ink tank 510. As shown in FIG. 9, the vicinity of the tip of the restricting protrusion 516 is located in the space inside the detection unit 540. That is, the tip of the regulation protrusion 516 is arranged in the upper part of the space inside the detection unit 540. Furthermore, a communication hole (not shown) for introducing air into the ink tank 510 is formed in the lid 515.

  Therefore, when ink is sufficiently stored in the ink tank 510 (at least to the extent that the ink level is positioned above the line A shown in FIG. 9), the buoyancy generated in the displacement member 570 is caused by gravity. Therefore, the detected portion 573 comes into contact with the tip of the restricting protrusion 516 like the displacement member 570 drawn with a broken line. That is, the upward displacement of the detected portion 573 is restricted by the restricting projection 516, and the detected portion 573 does not jump out of the space inside the detecting portion 540. At this time, the detected portion 573 is located at a detection position that blocks between the light emitting portion 2014a and the light receiving portion 2014b of the ink remaining amount detecting sensor 2014 provided in the ink jet recording apparatus 2000. This state is a state with ink, and the presence of ink is determined by a control board (not shown) of the ink jet recording apparatus 2000.

  Thereafter, when the ink in the ink tank 510 decreases and the ink level drops to the line A, the buoyancy generated in the displacement member 570 becomes equal to gravity. Further, when the ink level drops, the float portion 571 moves downward in the space extending in the vertical direction between the detecting portion 540 and the regulating wall 512 following the drop in the liquid level. And the to-be-detected part 573 connected to the float part 571 via the connection part 572 displaces below in the space in the detection part 540. When the ink remaining amount becomes almost zero and the float portion 571 comes into contact with the bottom wall of the ink tank 510, the detected portion 573 causes the light emitting portion 2014a and the light receiving portion 2014b of the ink remaining amount detecting sensor 2014 to Located in a non-detection position that does not block the gap. This state is a state of no ink, and the control board (not shown) of the ink jet recording apparatus 2000 determines whether there is no ink.

  The ink supply unit 520 includes a cylindrical ink supply path 521 that communicates with the ink tank 510 and extends in the vertical direction, and an ink supply mechanism 522 that is inserted into the ink supply path 521. The ink dispensing part 550 is provided on the bottom wall of the ink tank 510, communicates with the ink tank 510 and extends in the vertical direction, and is press-fitted into the dispensing cylinder part 551. And an ink dispensing plug 553. Since the functions of the ink supply unit 520 and the ink dispensing unit 550 are substantially the same as the functions of the ink supply unit 120 and the ink dispensing unit 150 of the first embodiment, description of these functions is omitted.

  The cap 530 has a light shielding property and is fixed to the ink tank 510 by ultrasonic welding or the like. As shown in FIG. 9, the front end of the ink supply path 521 and the dispensing cylinder portion 551 facing the bottom wall of the ink tank 510 and projecting downward from the bottom wall of the ink tank 510, and the bottom of the ink tank 510 A bottom wall 531 that contacts the ink supply path 521 and the tip of the rib 513 extending from the wall to the tip of the dispensing cylinder 551, and an upper edge of the bottom wall 531 extend upward. A side wall 535 is in contact with a part of the side surface of the injection tube portion 551 and the side surface of the rib 513. Openings 532 and 533 are respectively provided in portions of the bottom wall 531 corresponding to the ink supply path 521 and the dispensing cylinder portion 551. An annular protrusion 532 a that protrudes downward is formed at the edge portion of the opening 532 corresponding to the ink supply path 521.

  As described above, in the ink cartridge 500 of the present embodiment, as with the ink cartridge 1 of the first embodiment, the bubbles disappear quickly due to the diffusion surface 574 provided on the surface of the displacement member 570, and the displacement member Since the 570 can be normally displaced, the time delay until the remaining amount of ink can be accurately detected can be reduced.

  Further, in the ink cartridge 500 of the present embodiment, the displacement member 570 includes the detected portion 573 and the float portion 571 having a specific gravity smaller than that of the ink, and extends in the vertical direction, which is the displacement direction of the ink surface. The displacement path is regulated in the up and down direction by the regulating wall 512 to be performed. Therefore, as compared with the type in which the displacement member swings, the region in which the displacement member 570 is displaced is narrowed, so the degree of freedom in designing the ink cartridge 500 is increased.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various design changes can be made as long as they are described in the claims. Is. For example, in the above-described first embodiment, when the diffusion surface 474 is formed on a part of the float part 471 of the sensor arm 470 that is a displacement member and a part of the arm part 473 excluding the rib 473b, In the above embodiment, the case where the diffusing surface 574 is formed on the entire surface of the displacement member 570 has been described, but the present invention is not limited to this. The diffusion surface may be formed on at least one of a part of the region corresponding to the displacement path of the displacement member on the inner wall surface of the ink tank and a part of the surface of the displacement member. However, as described above, the inside of the detection units 140 and 540 is a narrow space, and air bubbles are easily retained. Therefore, it is most desirable that the diffusion surface is formed in the detection units 473a and 573.

  Further, in the first and second embodiments described above, the diffusion surface is composed of the reference surface and a plurality of protrusions protruding relative to the reference surface, and is formed between the adjacent protrusions. Although the case where the capillary force generation region is connected to another capillary force generation region has been described, the present invention is not limited to this. For example, the diffusing surface may be composed of a reference surface and a plurality of recessed portions that are recessed with respect to the reference surface, and the inside of the recessed portion may be a capillary force generation region. The diffusion surface may be composed of a reference surface, a plurality of protrusions, and a plurality of depressions.

  Furthermore, in the first and second embodiments described above, a case has been described in which the reference surface of the diffusion surface and the protrusion are connected at an angle of about 90 degrees so that a corner is formed. The connection angle between the reference plane and the protrusion is not limited to 90 degrees. Further, the reference surface and the protruding portion may be continuously connected so that the corner portion is not formed.

  Further, in the first embodiment described above, the ink tank 110 has a width narrower than the width of the main body 170 while projecting from the main body 170 and the main body 170 in the longitudinal direction, and has a vertical direction inside. Although the space which is connected to the main body 170 and is formed in the space and the detected portion 473a of the sensor arm 470 is displaced in the space has been described, the detection portion has been described. The form of 140 is not limited to this. Therefore, for example, the detection unit 140 may not protrude from the main body 170, and may have the same width as the main body 170.

  In the first and second embodiments described above, the sensor arm 470 and the displacement member 570 have a specific gravity smaller than the specific gravity of the ink. However, the specific gravity is not limited to this, and at least the float portions 471 and 571 are used. The specific gravity may be smaller than the specific gravity of the ink.

  In addition, in the first and second embodiments described above, when the ink cartridge is attached to the ink jet recording apparatus, the detection unit receives light from the light emitting part of the ink remaining amount detection sensor provided in the ink jet recording apparatus. Although the description has been given of the case where the detected part in the detection part is detected by the transmission type sensor provided at the position between the detection part and the transmission part, the present invention is not limited to this. For example, the detected part may be detected by a reflective sensor.

  Furthermore, in the first embodiment described above, the displacement range of the sensor arm 470 that is the displacement member is such that the arm holding portion 425 that pivotally supports the sensor arm 470 and the sensor arm 470 rotates to the float portion 471 side. In the second case, the bottom wall of the ink tank 110 in contact with the float portion 471 and the stopper 142 in contact with the detected portion 473a when the sensor arm 470 is rotated toward the detected portion 473a are secondly controlled. In the above embodiment, the case where the displacement range of the displacement member 570 is regulated in the vertical direction by the regulation wall 512 extending in the vertical direction that is the displacement direction of the ink liquid surface has been described. The aspect and the means for regulating the displacement range of the displacement member are not limited to these.

  In the first and second embodiments described above, when the ink is sufficiently stored in the ink tank, the detected portion of the displacement member (sensor arm) receives light from the light emitting portion of the ink remaining amount detection sensor. The case where the detected part opens the space between the light emitting part and the light receiving part of the ink remaining amount detection sensor when the ink in the ink tank is almost exhausted is described. First, when the ink is sufficiently stored in the ink tank, the detected part opens the space between the light emitting part and the light receiving part, and when the ink in the ink tank is almost exhausted, the light emitting part and the light receiving part You may block between.

  (Comparative Test 1) Here, like the diffusion surface formed on the surface of the displacement member of the first and second embodiments described above, the reference surface and a plurality of protrusions protruding relative to the reference surface are formed. From the diffusion surface, the reference surface, and a diffusion surface (Modification 1) composed of a plurality of depressions that are recessed relative to each other from the reference surface, the reference surface, a plurality of protrusions isolated from each other, and the plurality of depressions The comparison of the defoaming property between the diffusion surface (Modification 2) and the flat surface (Comparative Example 1) on which no irregularities are formed will be described. The difference in unevenness height (length from the reference surface to the bottom of the recess) of the diffusing surface of Modification 1 is 0.04 to 0.06 mm, the average diameter of the recess is 0.8 mm, and the difference between the reference surface and the recess is The area ratio is 0.5. The difference in uneven height (the length from the tip of the protrusion to the bottom of the recess) of the diffusion surface of Modification 2 is 0.04 to 0.06 mm, the average diameter of the protrusion and the recess is 0.8 mm, and the reference The area ratio of the surface to the protruding portion and the recessed portion is 0.5.

  An experiment was performed three times in which an ink bubble having a diameter of about 10 mm was attached to each of the four samples on which each diffusion surface and flat surface were formed, and the time until the bubbles disappeared was measured. The ink used is a water-soluble ink, and its surface tension is about 30 mN / m. The sample material is styrene resin. As a result of this experiment, the average value of three experiments with four samples is 23 minutes for the diffusion surface similar to the first and second embodiments, 29 minutes for the diffusion surface of Modification 1, and Modification 2 The diffusion surface was 26 minutes, and the flat surface of Comparative Example 1 was 31 minutes. Therefore, it can be seen that a diffusion surface composed of a reference surface and a plurality of protrusions protruding with respect to the reference surface, such as the diffusion surface of the first and second embodiments, has the best defoaming property.

  (Comparative Test 2) Next, the ink cartridge of the first embodiment and the sensor arm which is the same type as the first embodiment and has no diffusion surface, that is, a flat surface is attached. Using the ink cartridge (Comparative Example 2), an experiment was conducted to examine the behavior of the sensor arm. An amount of ink is stored in the ink tank of each ink cartridge so that the ink level is positioned in the middle in the longitudinal direction of the detection unit.

  First, the ink stored inside is forcibly bubbled, and the detected portion of the sensor arm sticks to the inner wall near the upper portion of the detecting portion via the bubble (that is, the sensor arm clockwise in FIG. 3). And the float part is in contact with the inner wall of the ink tank. Then, the time until the sensor arm returns to a normal position (position where the detected part comes into contact with the stopper) from this state was measured. The ink used is cyan at -20 ° C. As a result of performing the experiment twice with the ink cartridge of the first embodiment, the average value was 2 minutes. The result of conducting this experiment with the ink cartridge of Comparative Example 2 was 2 hours and 10 minutes. Therefore, by using the sensor arm with the diffusion surface formed as in the first embodiment, it is necessary for the sensor arm to be able to be displaced normally from the state in which the sensor arm cannot be displaced normally due to the influence of the surface tension of the foam. It has been found that the time can be greatly reduced.

1 is a perspective view of an ink cartridge according to a first embodiment of the present invention. FIG. 2 is an exploded view of the ink cartridge shown in FIG. 1. It is a figure of the ink storage body shown in FIG. It is a figure of the detection part vicinity shown in FIG. It is a figure of the sensor arm shown in FIG. It is a figure for demonstrating the diffusion surface shown in FIG. FIG. 2 is a diagram for explaining a method of mounting the ink cartridge shown in FIG. 1 to the ink jet recording apparatus. FIG. 6 is a diagram for explaining a method of detecting the remaining amount of ink in the ink tank indicated by 3 shown in FIG. 5. It is a figure which shows the ink cartridge which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,500 Ink cartridge 110,510 Ink tank 140 Detection part 170 Main part 470,570 Sensor arm (displacement member)
473a, 573 Detected part 142 Stopper (regulating means)
425 Arm clamping part (regulating means, support mechanism)
512 Restriction wall (regulation means, wall)
471 Float portion 474, 572 Diffusion surface 474a Reference surface 474b Projection portion 474c Corner portion 1000, 2000 Inkjet recording device 1014, 2014 Ink remaining amount detection sensor (transmission type optical sensor)
1014a, 2014a Light emitting part 1014b, 2014b Light receiving part

Claims (7)

An ink tank for storing ink;
A displacement member that is provided in the ink tank and is displaced in accordance with a decrease in the ink stored in the ink tank;
And a restricting means for restricting the displacement member to displace a predetermined displacement path,
A diffusion surface in which minute irregularities are formed so that capillary force is generated in at least one of a part of the inner wall surface of the ink tank corresponding to the displacement path and a part of the surface of the displacement member. An ink cartridge is provided.   The diffusion surface is composed of a reference surface and a plurality of protrusions protruding relative to the reference surface, and a capillary force generation region formed between the protrusions adjacent to each other is different from other capillary force generation regions. The ink cartridge according to claim 1, wherein the ink cartridge is connected.   The ink cartridge according to claim 2, wherein the reference surface and the protrusion are connected at an angle so as to have a corner. The ink tank includes a main body part, and a detection part that protrudes from the main body part and has a width narrower than the width of the main body part, and a space communicating with the inside of the main body part is formed inside. Has
The displacement member has a plate-like detected portion that is displaced in the space of the detection portion by the restriction of the restriction means;
The ink cartridge according to claim 1, wherein the diffusion surface is formed on a surface of the detected part.   The said detection part is provided in the position pinched | interposed by the light emission part and light-receiving part of the transmissive | pervious optical sensor provided in the said inkjet recording device, when it mounts | wears with an inkjet recording device. 5. The ink cartridge according to 4. The displacement member has the detected portion at one end and a float portion having a specific gravity smaller than that of the ink stored in the ink tank at the other end,
The restricting means includes a support mechanism that pivotally supports between the detecting portion and the float portion so that the displacement member can swing, and a restricting portion that restricts a swing range of the displacement member. The ink cartridge according to claim 4, wherein the ink cartridge is characterized in that: The displacement member includes the detected portion and a float portion having a specific gravity smaller than that of ink stored in the ink tank,
6. The ink cartridge according to claim 4, wherein the restricting unit includes a wall portion extending in a displacement direction of an ink liquid level accompanying a decrease in ink stored in the ink tank.

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