JP2005262564A - Ink cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To detect that an ink residue in an ink cartridge reaches a predetermined amount with a slight error. <P>SOLUTION: The ink cartridge has an ink chamber 31 which has a face to be contacted 56 extended nearly orthogonally to a displacement direction of an ink surface, and an inner wall face 34b extended in a vertical direction; and a light shielding plate 60 which is displaced in accordance with an increase or decrease of the ink in the ink chamber 31. The light shielding plate 60 is provided with a contact part 60a capable of selectively taking a position where it contacts the face to be contacted 56 and a position where it separates from the face to be contacted 56, in accordance with a position of the light shielding plate 60. A pin 59 is formed at a part opposite to the inner wall face 34b of the light shielding plate 60. The pin 59 is always opposed to the inner wall face 34b while the contact part 60a moves between the separation position and the contact position. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ink cartridge for storing ink.

  2. Related Art Inkjet printers that perform printing by ejecting ink from nozzles toward a recording sheet are known. Some ink jet printers can be attached and detached with ink cartridges. If the ink jet head ejects 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.

  In order to grasp the ink remaining amount, a method of calculating the used ink amount every time printing is performed and subtracting the sum from the initial ink amount can be considered. However, a large error tends to occur between the ink remaining amount calculated by such a method and the actual ink remaining amount. Therefore, in consideration of the error, ink ejection from the head must be prohibited when there is actually a sufficient amount of ink remaining. As a result, the ink cartridge in which a large amount of ink remains is discarded and new ink is used. It will be replaced with a cartridge.

  On the other hand, Patent Document 1 discloses a technique for accurately measuring the remaining amount of ink in an ink cartridge. In other words, in the ink cartridge described in Patent Document 1, an ink tank having a specific gravity smaller than that of ink is accommodated in the ink tank. Since the position along the vertical direction of the square changes depending on the remaining amount of ink, if the position of the square is detected, the amount of ink can be accurately measured, and then the remaining amount of ink in the ink cartridge can be measured. It can be detected with a small error that has reached a predetermined amount close to zero.

JP-A-9-001819 (FIG. 7)

  However, according to the technique described in Patent Document 1, due to the surface tension of the ink adhering to the inner wall surface of the ink tank, the surface sticks to the inner wall surface and does not descend as the ink surface decreases. is there. In such a case, it cannot be detected with a small error that the remaining amount of ink in the ink cartridge has reached a predetermined amount that is nearly zero.

  Therefore, a main object of the present invention is to provide an ink cartridge capable of detecting with a small error that the remaining amount of ink in the ink cartridge has reached a predetermined amount.

Means for Solving the Problems and Effects of the Invention

  An ink cartridge according to the present invention is an ink tank in which ink is stored. The ink tank has a downwardly inclined inner surface extending in a downwardly inclined direction with respect to the ink surface, and is stored in the ink tank. A displacement member that displaces in the ink tank as the ink amount increases and decreases, and a restriction surface that restricts the displacement of the displacement member. The displacement member includes the displacement member according to the position of the displacement member. A contact portion that can selectively take a position that contacts the restriction surface and a position that is separated from the restriction surface is formed, and a portion of the displacement member that faces the lower inclined inner surface is provided with the contact portion. During the movement between the separated position and the abutting position, a convex portion is formed that always faces the downwardly inclined inner surface.

  According to the present invention, since the distance between the displacement member and the downwardly inclined inner surface is maintained by the convex portion, the displacement member and the downwardly inclined inner surface are bonded by the surface tension of the ink, or the smoothness of the displacement of the displacement member is impaired. Can be prevented. As a result, it is possible to detect with a small error that the displacement member smoothly moves in accordance with the change in the remaining amount of ink and the remaining amount of ink in the ink chamber 31 reaches a predetermined amount.

  In the present invention, the ink tank is formed with a recess in which the two downwardly inclined inner surfaces are opposed to each other, and at least a part of the displacement member is between the two downwardly inclined inner surfaces that are opposed in the recess. It is preferable that the convex portions protrude from the portions of the displacement member facing the two downwardly inclined inner surfaces toward the downwardly inclined inner surfaces, respectively. According to this, the distance between the downward inclined inner surface of the concave portion and the displacement member can be shortened to narrow the width of the concave portion. Thereby, it becomes easy to detect a displacement member from the outer side of a recessed part.

  Further, in the present invention, the displacement member is formed with a thin plate-shaped portion sandwiched between the two downwardly inclined inner surfaces facing each other in the recess when the contact portion is in the contacted position. It is preferable that the convex portion protrudes from the thin plate portion. According to this, the width of the recess can be further reduced.

  Furthermore, in this invention, it is preferable that the rib protrudes toward the said displacement member from the part which faces the said displacement member among the two said downward inclined inner surfaces. According to this, since the ink remaining between the downwardly inclined inner surface and the displacement member falls downward along the rib, it is further prevented that the downwardly inclined inner surface and the displacement member are bonded by the surface tension of the ink. be able to.

  At this time, it is more preferable that the rib is provided continuously along the displacement trajectory of the displacement member. According to this, the ink remaining between the downward inclined inner surface and the displacement member can be efficiently dropped downward.

  In this invention, it is preferable that the front-end | tip part of the said convex part is comprised by the curved surface which protrudes toward the said downward inclined inner surface. According to this, since the convex portion comes into contact with the downwardly inclined inner surface at a point, it becomes difficult to be influenced by the surface tension of the ink, so that the displacement member can be smoothly displaced.

Further, in the present invention, the contact portion is a columnar protrusion extending along the ink surface,
It is preferable that when the abutting portion abuts at least the regulation surface, a wall intersecting the regulation surface is erected in the vicinity in the extending direction of the abutting portion. According to this, since the contact portion and the regulation surface are in contact with each other by a line, the contact portion and the regulation surface are not easily bonded by the surface tension of the ink. Furthermore, since the ink accumulated on the regulation surface is sucked and removed by the capillary force of the ridgeline formed between the wall surface and the contact portion and the regulation surface are bonded by the surface tension of the ink. Further, it can be prevented.

  Furthermore, in the present invention, the regulating surface may be a slope that intersects the ink surface. As a result, the ink collected on the regulating surface flows down along the inclination, so that the ink hardly accumulates on the regulating surface.

  In addition, according to the present invention, the displacement member is formed in the ink tank around an axis orthogonal to the displacement direction of the ink surface accompanying the use of ink as the amount of ink stored in the ink tank increases or decreases. It is preferable to rotate at. According to this, since the orbit of the displacement member is stabilized, the downward inclined inner surface and the displacement member are hardly bonded by the surface tension of the ink.

  Furthermore, in the present invention, the convex portion and the downward inclined inner surface facing the convex portion may be formed in the vicinity of the end portion of the displacement member. According to this, it is possible to reliably prevent the displacement member from being bonded to the lower inclined inner surface due to the surface tension of the ink.

  Or in this invention, the said convex part and the said downward inclined inner surface facing this may be formed in the said shaft vicinity of the said displacement member. According to this, since the displacement range of a convex part becomes narrow, the downward inclined inner surface facing a convex part can be made small.

  In addition, according to the present invention, the ink tank stores ink, a restriction surface that is substantially orthogonal to a displacement direction of the ink surface that accompanies use of the ink, and one end of the restriction surface to the restriction surface. An ink tank having a downwardly inclined inner surface extending in a downwardly inclined direction, and a displacement member that is displaced in the ink tank as the amount of ink stored in the ink tank increases or decreases, The displacement member is formed with a contact portion that can selectively take a position that contacts the restriction surface and a position that is separated from the restriction surface according to the position of the displacement member, and the inner wall of the ink tank Are formed with recesses facing the two downwardly inclined inner surfaces, and at least a part of the displacement member is sandwiched between the two downwardly inclined inner surfaces facing each other in the recesses, A convex portion which always faces each downwardly inclined inner surface while the abutting portion moves between the separated position and the abutting position from a portion of the positioning member facing the downwardly inclined inner surface. Projecting toward the downwardly inclined inner surface, and ribs projecting toward the displacement member from portions of the two downwardly inclined inner surfaces facing the displacement member.

A first embodiment of the present invention will be described. In the first embodiment, the present invention is applied to an inkjet printer capable of ejecting four colors of ink.
As shown in FIG. 1, the ink jet printer 1 includes a nozzle 2 a that ejects four colors of ink of cyan (C), yellow (Y), magenta (M), and black (K) on the recording paper P. Inkjet head 2 and four holders 4 (4a, 4b, 4c, 4d) as cartridge mounting portions on which four ink cartridges 3 (3a, 3b, 3c, 3d) for storing four color inks are mounted, respectively The carriage 5 that linearly reciprocates the inkjet head 2 along the guide 9 in one direction (perpendicular to the paper surface), and the recording paper P perpendicular to the movement direction of the inkjet head 2 and the inkjet head 2 A transport mechanism 6 that transports the ink in the direction parallel to the ink ejection surface, and a purge device that sucks the air in the inkjet head 2 and the ink with increased viscosity 7, a control device 8 or the like which controls overall control of the inkjet printer 1.

  In the ink jet printer 1, the recording paper P is transported in the left-right direction in FIG. 1 by the transport mechanism 6 while the ink jet head 2 is reciprocated in the direction perpendicular to the paper surface of FIG. In conjunction with this, ink is supplied from the holder 4 to which the ink cartridge 3 is mounted via the supply tube 10 to the nozzle 2a of the inkjet head 2, and ink is discharged from the nozzle 2a toward the recording paper P. The recording paper P is printed.

  Further, the purge device 7 is movable in a direction approaching / separating from the ink discharge surface and can be mounted on the inkjet head 2 so as to cover the ink discharge surface, and suction for sucking ink from the nozzle 2a. A pump 70 is provided. When the inkjet head 2 is out of the printable range for printing on the recording paper P, the air mixed in the inkjet head 2 or the ink whose viscosity has been increased by evaporation of the nozzles is sucked by the suction pump 70. It is possible to suck from 2a.

  The four holders 4a to 4d are arranged in a line, and four ink cartridges 3a to 3d for storing cyan, yellow, magenta, and black ink are mounted on the four holders 4a to 4d, respectively. . Here, among the four color inks, the black ink is often used more frequently than the other three color inks. In this case, the capacity of the black ink cartridge is less than the color ink. It is preferably larger than the ink cartridges 3a to 3c.

  At the bottom of the holder 4, an ink supply pipe (communication pipe) 12 and an air introduction pipe 13 are respectively erected at positions corresponding to an ink supply valve 21 and an air introduction valve 22 of the ink cartridge 3 to be described later. The holder 4 is also provided with an optical sensor 14 (transmission type optical sensor) for detecting the remaining amount of ink in the ink cartridge 3. The sensor 14 has a light emitting portion 14a and a light receiving portion 14b attached to face each other so as to sandwich the ink cartridge 3 from both sides at the same height, and light from the light emitting portion 14a is contained in the ink cartridge 3 described later. It is detected whether or not the shutter mechanism 23 provided in is shut off, and is output to the control device 8.

  Next, the ink cartridge 3 will be described in detail. Since the ink cartridges 3a to 3c for storing the three kinds of color inks and the ink cartridge 3d for storing the black ink have the same structure, only one of them will be described.

  As shown in FIGS. 2 to 4, the ink cartridge 3 includes a cartridge main body 20 that stores ink, an ink supply valve 21 that can open and close an ink supply channel that supplies ink in the cartridge main body 20 to the ink cartridge 3, and An air introduction valve 22 that can open and close an air introduction path for introducing air into the cartridge body 20 from the outside, a shutter mechanism 23 that blocks light from the light emitting portion 14a of the sensor 14 that detects the remaining amount of ink, and the cartridge body 20 and a cap 24 that covers the lower end of 20.

  The cartridge body 20 is formed of a synthetic resin having light permeability. As shown in FIG. 4, a horizontally extending partition wall 30 is integrally formed in the cartridge main body 20, and the inner wall of the cartridge main body 20 is separated from the upper ink chamber (ink tank) 31 by the partition wall 30. It is partitioned into two valve housing chambers 32 and a valve housing chamber 33 on the side. The ink chamber 31 is filled with ink of each color, and the ink supply valve 21 and the air introduction valve 22 are respectively stored in the two valve storage chambers 32 and 33. At this time, an ink supply passage for guiding the ink filled in the ink chamber 31 to the outside is configured in the valve storage chamber 32. As will be described later, in this ink supply passage, an ink flow is formed downward from the ink chamber 31 side (see FIG. 9B). As shown in FIGS. 2B and 2C, the side wall portion of the ink chamber 31 protrudes slightly outward and extends along the downward direction at a substantially central position in the height direction. A protrusion 34 is formed. When the ink cartridge 3 is mounted on the holder 4, the light emitting portion 14 a and the light receiving portion 14 b of the sensor 14 provided on the holder 4 are positioned at the same height as the protruding portion 34 formed on the side wall portion of the cartridge body 20. To do.

  As further shown in FIGS. 5 to 7, a recess 34 a is formed inside the protrusion 34 in the ink chamber 31. The recess 34a extends in a direction perpendicular to the ink surface (a direction inclined downward) and has inner wall surfaces (downwardly inclined inner surfaces) 34b facing each other. In the recess 34a, a light shielding plate 60 of the shutter mechanism 23 described later is disposed so as to be sandwiched between two inner wall surfaces 34b. Each inner wall surface 34b is formed with a rib 58 that protrudes toward the light-shielding plate 60 disposed in the recess 34a and extends in the vertical direction. Further, two contacted surfaces (regulating surfaces) 56 that are adjacent to each inner wall surface 34 b and extend in parallel with each other in the same plane are formed in the ink chamber 31. The abutted surface 56 abuts against a later-described abutting portion 60 a of a light shielding plate 60 and is an inclined surface that is inclined toward the bottom surface of the ink chamber 31 (intersects with the ink surface). In addition, a vertical wall surface 69 is formed adjacent to the inner wall surface 34 b and the contacted surface 56, and the contact surface 56 abuts against the contacted surface 56 so as to straddle the contacted surface 56 and the vertical wall surface 69. Ribs 57 are formed so as to be orthogonal to the extending direction of the contact portion 60a. When the contact portion 60 a is in contact with the contacted surface 56, the tip of the contact portion 60 a is adjacent to the side surface of the rib 57. Further, the rib 57 is continuous from one end to the other end of the abutted surface 56 and from one end to the other end of the vertical wall surface 69. As shown in FIG. 8, a curve (for example, A in the figure) straddling the rib 57 and the contacted surface 56 in the vicinity of the boundary between the rib 57 and the contacted surface 56 is all of the rib 57 and the vertical wall surface 69. The curvature is smaller than a curve (for example, B and C in the figure) straddling the rib 57 and the vertical wall surface 69 in the vicinity of the boundary. Further, a curve (for example, B in the figure) straddling the rib 57 and the vertical wall surface 69 in the vicinity of the boundary between the rib 57 and the vertical wall surface 69 is a rib near the boundary between the rib 57 and the vertical wall surface 69. The curvature is smaller than a curve (for example, C in the figure) straddling 57 and the vertical wall surface 69.

  As shown in FIGS. 4 to 7, the shutter mechanism 23 is provided in a space below the ink chamber 31, and includes a light shielding plate 60 that does not transmit light, a hollow float 61, a light shielding plate 60, and a float. And a support base 63 that is provided on the upper side of the partition wall 30 and rotatably supports the connection member 62. The light shielding plate 60, the float 61, and the connecting member 62 constitute a displacement member. The float 61 is a cylindrical member having a sealed space filled with air inside, and the specific gravity of the entire float 61 is smaller than the specific gravity of the ink in the ink chamber 31. The light shielding plate 60 and the float 61 are provided at both ends of the connecting member 62, respectively. At the center of the connecting member 62, a cylindrical rotating shaft 62a protruding in a direction perpendicular to the plane of the connecting member 62 is formed, and the support base 63 has the rotating shaft 62a (on the paper surface of FIG. 4). It is supported rotatably (in parallel vertical planes).

  The rotation shaft 62a protrudes from the flat surfaces on both sides of the connecting member 62 in the direction perpendicular to the displacement direction of the ink surface. Further, the rotation shaft 62a is supported by the support base 63 so that the rotation shaft 62a can be slightly rotated even in the plane of FIG. 6 in order to ensure smooth rotation. That is, the support base 63 supports the displacement member from below so as to allow movement other than rotation about the rotation shaft 62a. The leading ends of the rotating shafts 62a in the projecting direction are in contact with the side walls of the support plate 63a standing from the bottom surface (partition wall 30: described later) of the ink chamber 31. The displacement member is restricted from causing an overall displacement in the direction.

  The light shielding plate 60 is a thin plate-like member that is parallel to the vertical surface and has a predetermined area. Further, as shown in FIG. 4, the light shielding plate 60 includes a rectangular region and a triangular projecting region formed so as to extend further upward from the upper end of the rectangular region. . A contact portion 60a having a column shape protruding from the light shielding plate 60 toward the two ribs 57 (direction along the ink surface) is formed at the upper end of the protruding region. The abutting portion 60a abuts against the abutted surface 56, thereby restricting the rotation of the connecting member 62 and disposing the light shielding plate 60 at a predetermined position. Specifically, when the contact portion 60a contacts the contacted surface 56, the light shielding plate 60 is disposed at a detection position between the light emitting portion 14a and the light receiving portion 14b in the recess 34a. At this time, the light shielding plate 60 blocks light transmitted through the wall of the translucent cartridge body 20 and the ink in the ink chamber 31 from the light emitting portion 14 a of the sensor 14. On the contrary, when the contact portion 60a is separated from the contacted surface 56, the light shielding plate 60 is disposed at a position other than the detection position. At this time, the light from the light emitting unit 14a reaches the light receiving unit 14b without being blocked.

  Accordingly, in a state where the ink remaining amount in the ink chamber 31 is large and the entire float 61 provided at one end of the connecting member 62 is located in the ink, the float 61 floats due to buoyancy and the light shielding provided at the other end. The plate 60 is located at a position (solid line in FIG. 4) that blocks light from the light emitting part 14a in the protruding part. However, when the remaining amount of ink in the ink chamber 31 decreases and a part of the float 61 is exposed from the ink surface, the buoyancy acting on the float 61 is reduced and the float 61 is lowered. Then, since the light shielding plate 60 moves to a position above the inside of the projecting portion 34 where the light shielding plate 60 does not block the direct light from the light emitting portion 14a (the position of the chain line in FIG. 4), the direct light from the light emitting portion 14a. Is transmitted through the light-transmitting protrusion 34 in a straight light path and is directly received by the light receiving portion 14b. In this way, the sensor 14 detects a state in which the remaining amount of ink in the ink chamber 31 is low.

  Pins (convex portions) 59 having columnar shapes protruding from the light shielding plate 60 toward the inner wall surface 34b are formed on both planes of the rectangular region of the light shielding plate 60 (near the end of the displacement member). The tip of the pin 59 is a curved surface. As shown in FIG. 4, the tip of the pin 59 is always at the inner wall surface 34 b in a range in which the contact portion 60 a moves between a position where the contact portion 60 a is in contact with the contacted surface 56 and a position where it is separated from the contacted surface 56. It comes to oppose. The pin 59 is such that even when the tip of the pin 59 is in contact with the inner wall surface 34b and the light shielding plate 60 is closest to the inner wall surface 34b, a capillary phenomenon does not occur between them due to at least the surface tension of the ink. It has a protruding amount that creates a gap.

  When the ink cartridge 3 is mounted on the holder 4, the protruding portion 34 is sandwiched between the light emitting portion 14 a and the light receiving portion 14 b of the sensor 14. At this time, since the width of the protruding portion 34 is shorter than the distance between the light emitting portion 14a and the light receiving portion 14b, a predetermined interval is maintained between the light emitting portion 14a and the light receiving portion 14b and the protruding portion 34. Yes. As shown in FIGS. 2 and 3, a pair of ribs 55 extending along the protruding portion 34 so as to sandwich the protruding portion 34 are formed at both ends in the horizontal direction of the outer wall where the protruding portion 34 is formed. ing. A lid member 35 is welded to the upper end portion of the cartridge body 20, and the ink chamber 31 in the cartridge body 20 is closed by the lid member 35.

  As shown in FIG. 4, an injection hole 36 for injecting ink into the ink chamber 31 of the empty ink cartridge 3 is formed between the two valve storage chambers 32, 33. A plug member 37 made of synthetic rubber is press-fitted into the case. Further, the back end of the injection hole 36 communicates with the ink chamber 31 in the cartridge body 20. When the ink is filled, an injection needle (not shown) passes through the plug member 37 in the injection hole 36, and the ink is filled into the ink chamber 31 through the injection needle.

  A cylindrical portion 38 that protrudes downward is integrally formed at a portion of the partition wall 30 that constitutes the ceiling portion of the valve accommodating chamber 32 in which the ink supply valve 21 is accommodated, and at the lower end of the cylindrical portion 38. A thin film portion 39 that closes the communication path formed in the cylindrical portion 38 is provided. On the other hand, two cylindrical portions 40 and 41 projecting upward and downward respectively are integrally formed on the partition wall 30 constituting the ceiling portion of the valve accommodating chamber 33 in which the air introduction valve 22 is accommodated. At the lower end of the cylindrical portion 41 on the side, a thin film portion 42 that closes the communication path formed in the cylindrical portions 40 and 41 is provided. Further, a cylindrical member 43 extending to the upper end portion of the ink chamber 31 is provided on the upper side of the cylindrical portion 40.

  As shown in FIG. 4, the ink supply valve 21 includes a valve body 45 formed in a substantially cylindrical shape with a synthetic rubber or the like and having elasticity, and a valve body 46 made of a synthetic resin housed in the valve body 45. I have. As shown in FIG. 9, the valve main body 45 is configured by integrally forming an urging portion 47, a valve seat portion 48, and a fitting portion 49 that are arranged in order from the upper side (the ink chamber 31 side).

  The lower surface of the valve body 46 is in contact with the upper surface (the end surface on the ink chamber 31 side) of the valve seat portion 48, and a through hole 48a extending in the vertical direction is formed on the axial center portion of the valve seat portion 48. Is formed. The fitting portion 49 is formed with a guide hole 49a that communicates with the through hole 48a and extends downward, and the guide hole 49a is formed in a divergent shape whose diameter increases toward the bottom. An annular groove 49b is formed around the guide hole 49a, and the wall portion forming the guide hole 49a can be easily elastically deformed in the direction in which the guide hole 49a expands in diameter. Therefore, when the ink supply pipe 12 is inserted into the guide hole 49a, the adhesion between the guide hole 49a and the ink supply pipe 12 can be improved to prevent ink leakage as much as possible. Even when the ink supply tube 12 is inserted in an inclined state or a deviated state with respect to the guide hole 49a, the wall portion is deformed in the direction in which the guide hole 49a expands. 49a is securely inserted.

  The urging portion 47 includes a cylindrical side wall portion 47a that rises from the outer peripheral side portion of the valve seat portion 48 to the ink chamber 31 side, and an overhang portion 47b that integrally protrudes radially inward from the upper end of the side wall portion 47a. And have. The lower surface of the overhang portion 47b is in contact with the valve body 46, and the valve body 46 is urged downward by the elastic force of the side wall portion 47a and the overhang portion 47b. Further, an opening 47c is formed inside the overhanging portion 47b, and the side wall portion 47a and the overhanging portion 47b that are integrally formed can be easily elastically deformed.

  As shown in FIGS. 9 and 10, the valve body 46 includes a bottom portion 50 that contacts the valve seat portion 48, a cylindrical valve side wall portion 51 that extends from the outer peripheral side portion of the bottom portion 50 toward the ink chamber 31, and a bottom portion. 50 and a break portion 52 that protrudes further toward the ink chamber 31 than the valve side wall portion 51.

  An annular protrusion 50 a that protrudes toward the valve seat portion 48 is formed on the lower surface of the bottom portion 50 (the end surface facing the valve seat portion 48). When the urging portion 47 urges the valve body 46 toward the valve seat portion 48, and the annular protrusion 50 a is in close contact with the upper surface of the valve seat portion 48, the through hole 48 a of the valve seat portion 48 has the valve body. The ink supply channel is closed by being blocked by 46. Furthermore, the space above the valve body 46 and the space below are communicated with each other at a circumferentially equal position in the portion of the bottom 50 on the outer peripheral side of the annular protrusion 50a and the inner peripheral side of the valve side wall 51. A plurality of (for example, eight) communication passages 53 are formed.

  As shown in FIGS. 9 and 10, the breaking portion 52 is composed of four plate members 52 a, 52 b, 52 c, 52 d combined in a cross shape in plan view, and stands upright at the substantially central portion of the bottom portion 50. Has been. Further, grooves 54 extending in the vertical direction are formed between the four plate members 52a to 52d. And the fracture | rupture part 52 protrudes upwards through the opening 47c inside the overhang | projection part 47b, and the front-end | tip is arrange | positioned in the position a little lower than the thin film part 39, as shown in FIG.

  When the ink cartridge 3 is mounted in the holder 4, the ink supply pipe 12 provided in the holder 4 is inserted into the guide hole 49a. Then, the valve body 46 is pushed up against the urging force of the urging portion 47 by the tip of the ink supply pipe 12, and the valve body 46 moves upward while deforming the urging portion 47. The protrusion 50 a is separated from the valve seat portion 48. At this time, since the thin film portion 39 is broken by the tip of the breaking portion 52 of the valve body 46 that has moved upward, the ink in the ink chamber 31 flows into the cylindrical portion 38 as shown in FIGS. The ink flows into the valve housing chamber 32 through the internal communication passage, and ink is supplied from the ink supply pipe 12 to the ink jet printer 1 through the communication passage 53 of the valve body 46. At this time, the valve storage chamber 32 functions as an ink supply passage, and an ink flow is formed downward from the ink chamber 31 side.

  The air introduction valve 22 includes a valve main body 45 and a valve body 46 accommodated in the valve main body 45, and has the same configuration as the ink supply valve 21. That is, the valve body 46 urged downward by the urging portion 47 is in close contact with the valve seat portion 48 of the valve main body 45 so that the valve body 46 closes the through hole 48a. When the ink cartridge 3 is attached to the holder 4, the air introduction pipe 13 is inserted into the guide hole 49 a formed in the valve body 45, and the valve body 46 moves upward in the same manner as the ink supply valve 21. The thin film portion 42 of the tubular portion 41 is broken by the breaking portion 52. Then, the external atmosphere flows into the valve accommodating chamber 33 from the atmosphere introducing pipe 13 through the communication passage 53 of the valve body 46, and further, the ink chamber through the cylindrical portions 40 and 41 and the internal passage of the cylindrical member 43. Atmosphere is introduced into the upper part of 31.

  Unlike the cartridge main body 20, the cap 24 is formed of a non-translucent material that does not transmit light. As shown in FIGS. 2 to 4, the cap 24 is fixed to the cartridge body 20 by ultrasonic welding or the like with the lower end portion of the cartridge body 20 covered. Two annular projections 65 projecting downward are formed at positions corresponding to the ink supply valve 21 and the air introduction valve 22 at the bottom of the cap 24, respectively, when the ink cartridge 3 is placed on a desk or the like. Ink near the inlets of the ink supply valve 21 and the air introduction valve 22 is less likely to adhere to the surface of the desk.

  A rib 66 extending in the vertical direction is formed on the side wall of the cap 24 on the same side as the protrusion 34 formed on the cartridge body 20. As shown in FIGS. 2B and 4, the rib 66 and the light shielding plate 60 in the protruding portion 34 of the cartridge main body 20 are disposed at a position separated by a predetermined distance along the vertical direction. Is located below the light shielding plate 60. Therefore, in a state where the ink cartridge 3 is mounted on the holder 4, the rib 66 is at a position below the light emitting portion 14 a and the light receiving portion 14 b of the sensor 14. Further, the rib 66 is located between the light emitting portion 14a and the light receiving portion 14b of the sensor 14 in a plan view when the ink cartridge 3 is viewed from the mounting direction. Further, the rib 66 has a narrower width than the protruding portion 34, and the rib 66 has a protruding distance shorter than the protruding distance of the protruding portion 34.

  The rib 66 passes between the light emitting unit 14 a and the light receiving unit 14 b only from the light emitting unit 14 a of the sensor 14 when the ink cartridge 3 is attached to the holder 4 or when the ink cartridge 3 is removed from the holder 4. Is detected by instantaneously blocking the light. On the other hand, in the mounted state of the ink cartridge 3, the ribs 66 are not detected by the sensor 14, and only the light shielding plate 60 provided in the ink chamber 31 can be detected by the sensor 14. That is, when the rib 66 is detected by the sensor 14 only when the ink cartridge 3 is attached or detached, it can be recognized whether or not the ink cartridge 3 is mounted by the control device 8 described later. Further, the rib 66 is detected by the sensor 14 only by attaching and detaching the ink cartridge 3 in one direction. Therefore, a complicated operation for detecting the rib 66 by the sensor 14 is not required, and the rib 66 exposed to the outside and weak in strength contacts the holder 4 and is damaged. It can be prevented as much as possible.

  Next, the control device 8 will be described. The control device 8 controls various operations of the ink jet printer 1 such as ejection of ink from the nozzles 2 a of the ink jet head 2, paper feeding to the ink jet head 2, paper discharge printed by the ink jet head 2, and the like. The control device 8 includes a central processing unit (CPU) that is an arithmetic processing device, a read-only memory (ROM) that stores a program executed by the CPU and data used for the program, and a program A RAM (Random Access Memory) for temporarily storing data at the time of execution, a nonvolatile memory such as a rewritable EEPROM (Electrically Erasable Programmable Read-Only Memory), an input / output interface, a bus, and the like. As shown in FIG. 1, the control device 8 is based on various signals input from an external personal computer (PC) 82, the inkjet head 2, the motor of the transport mechanism 6 that drives the carriage 5, and the purge device 7. The various devices constituting the inkjet printer 1 such as the suction pump 70 are controlled.

  Further, the control device 8 determines a mounting state determination unit 80 that determines a mounting state of the ink cartridge 3 in the holder 4 based on an output signal from the sensor 14, and an ink remaining amount for calculating the ink remaining amount in the ink chamber 31. And a calculation unit 81.

  Hereinafter, the operation of the mounting state determination unit 80 and the remaining ink amount calculation unit 81 will be described with reference to the flowchart of the mounting state determination process in FIG. Here, Si (i = 10, 11, 12,...) In FIG. 11 indicates each step. This flowchart shows an example of what is applied when the ink cartridge 3d for storing black ink is attached to the holder 4d.

  First, when the rib 66 provided on the cap 24 is not detected by the sensor 14 in a state where the power of the inkjet printer 1 is turned on (S10: No), the process proceeds to the remaining ink amount calculation process of S14. . When the rib 66 is detected by the sensor 14 (S10: Yes), if the ink cartridge 3d is attached to the holder 4d immediately before the detection of the rib 66 (S11: Yes), the ink cartridge 3d is held in the holder. It is determined that the ink cartridge 3d has been removed, and information corresponding to the fact that the ink cartridge 3d is not attached is stored (S12). Further, since it is not necessary to calculate the remaining ink amount, the process returns as it is.

  If the ink cartridge 3d is not attached immediately before the detection of the rib 66 (S11: No), the ink cartridge 3d is attached to the holder 4d, so that the rib 66 of the ink cartridge 3d shown in FIG. 3 is detected. Therefore, information corresponding to the ink cartridge 3d being in the mounted state is stored (S13). Further, the process proceeds to the ink remaining amount calculation process of S14.

  In the remaining ink amount calculation process of S14, when the light shielding plate 60 of the shutter mechanism 23 is detected (when the remaining ink amount is sufficient), the maximum capacity of the ink cartridge 3d and the ink cartridge 3d are attached. The approximate ink remaining amount is calculated from the integrated value of the number of ejected ink droplets. On the other hand, when the light shielding plate 60 of the shutter mechanism 23 is not detected (when the ink remaining amount is low), the ink remaining amount in a state where the light shielding plate 60 is no longer detected, and the state is reached. A more accurate ink remaining amount is calculated from the integrated value of the number of ejected ink droplets. Then, the ink remaining amount calculated in S14 is transferred to the PC 82 (S15), and the process returns.

  Note that information such as the mounting state of the ink cartridge 3 and the integrated value of the ejected dots is stored in a nonvolatile memory such as an EEPROM so that the information is retained even when the power of the inkjet printer 1 is turned off.

  According to the first embodiment described above, the distance between the light shielding plate 60 and the inner wall surface 34 b is maintained by the pin 59. At this time, a distance is secured between the light shielding plate 60 and the inner wall surface 34b so that capillary action does not occur due to the surface tension of the ink, and the light shielding plate 60 and the inner wall surface 34b are bonded by the surface tension of the ink. It is possible to prevent the smoothness of the displacement of the light shielding plate 60 from being impaired. In other words, the surface of the ink interposed between the light shielding plate 60 and the inner wall surface 34b can be lowered in the same manner as the ink surface is reduced due to the consumption of the ink. Ink that prevents the displacement of the ink does not remain. Therefore, it is possible to detect with a small error that the light shielding plate 60 moves smoothly with a change in the remaining amount of ink and the remaining amount of ink in the ink chamber 31 reaches a predetermined amount.

  Further, since the displacement member is supported so as to be able to turn somewhat in the plane of FIG. 6, depending on the distance between the light shielding plate 60 and the inner wall surface 34b, the displacement member is provided at a position away from the support point. It occurs that the light shielding plate 60 gets too close to the inner wall surface 34b. In view of this, if the distance between the two is wide, it is not necessary to be affected by the surface tension of the ink that impairs the smooth movement of the light shielding plate 60. However, the light emitting unit 14a and the light receiving unit 14b of the sensor 14 Needs to be widened, which is not a good idea in terms of the sensitivity of the sensor 14. Depending on the distance between the light emitting part and the light receiving part, it is necessary to use an expensive sensor with higher sensitivity. However, in the present embodiment, the distance between the light shielding plate 60 and the inner wall surface 34b is regulated by the pin 59 to such an extent that the smooth movement of the light shielding plate 60 is not impaired by the surface tension of the ink. 59, the distance between the light shielding plate 60 and the inner wall surface 34b can be shortened. At the same time, the width of the protrusion 34 can be reduced. Furthermore, since the light shielding plate 60 has a thin plate shape, the width of the protruding portion 34 can be further reduced. Thereby, the sensor 14 which is an inexpensive transmissive optical sensor can be used.

  In addition, since the rib 58 is formed on the inner wall surface 34b, the ink accumulated between the light shielding plate 60 and the inner wall surface 34b can be dropped along the rib 58 downward. Thereby, it is possible to further prevent the light shielding plate 60 and the inner wall surface 34b from being bonded due to the surface tension of the ink.

  Furthermore, since the tip of the pin 59 is formed of a curved surface, and the pin 59 contacts the inner wall surface 34b at a point, ink may remain between the pin 59 and the inner wall surface 34b. The residual amount can be minimized. That is, the pin 59 and the inner wall surface 34b are not easily bonded by the surface tension of the ink. Therefore, it is possible to detect with a small error that the light shielding plate 60 moves smoothly with a change in the remaining amount of ink and the remaining amount of ink in the ink chamber 31 reaches a predetermined amount.

  Further, since the contact portion 60a is columnar and the contact portion 60a and the contacted surface 56 are in contact with each other by a line, the contact portion 60a and the contacted surface 56 are not easily bonded by the surface tension of the ink. . Therefore, it is possible to detect with a small error that the light shielding plate 60 moves smoothly with a change in the remaining amount of ink and the remaining amount of ink in the ink chamber 31 reaches a predetermined amount.

  Further, the ink accumulated on the contacted surface 56 is sucked by the capillary force of the ridge formed between the contacted surface 56 and the rib 57, and further drops downward along the rib 57. Therefore, the contact portion 60a and the contacted surface 56 are not easily bonded by the surface tension of the ink. At the same time, in the state where the contact portion 60a is in contact with the contacted surface 56, the tip of the contact portion 60a is adjacent to the side surface of the rib 57, so the contact portion 60a and the contacted surface The ink held between the contacted surface 56 and the rib 57 is also sucked by the capillary force of the ridge formed between the contacted surface 56 and the rib 57. Therefore, the contact portion 60a can be easily separated from the contacted surface 56 at an appropriate timing in accordance with the decrease in the ink surface.

  At this time, the curve (C) straddling the rib 57 and the lower end region of the vertical wall surface 69, the curve (B) straddling the rib 57 and the upper end region of the vertical wall surface 69, and the rib 57 and the contacted surface 56 are straddled. The curvature decreases in the order of the curve (A). As a result, the capillaries at the ridges formed by the wall surfaces become larger at the portion located below the ribs 57, and work as a whole to move the ink further downward. That is, the ink collected near the boundary between the abutted surface 56 and the rib 57 is more likely to fall down along the rib 57.

  In addition, the abutted surface 56 is an inclined surface, and the ink accumulated on the abutted surface 56 flows downward along the inclination, so that the ink is more unlikely to accumulate on the abutted surface 56.

  Furthermore, since the connecting member 62 provided with the light shielding plate 60 is rotated, the light shielding plate 60 is displaced, so that the light shielding plate 60 can be displaced along the track in a predetermined stable manner. For this reason, the light shielding plate 60 is less likely to be bonded to the inner wall surface 34b outside the predetermined track.

  Next, a second embodiment will be described with reference to the drawings. In the second embodiment, substantially the same members as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted. By moving the contact portion 60a from a position where the contact portion 60a contacts the contacted surface 56 to a position separated from the contacted surface 56, the light shielding plate 60 is displaced so as to draw an arc. As shown in FIG. 12, each inner wall surface 34b extends continuously while curving along the displacement trajectory of the light shielding plate 60, and projects toward the light shielding plate 60 disposed in the recess 34a. A rib 58A is formed.

  According to the second embodiment described above, the ink accumulated between the area where the light shielding plate 60 is displaced and the inner wall surface 34b can be dropped downward along the rib 58A. Thereby, it can prevent that the light-shielding plate 60 and the inner wall face 34b adhere | attach by the surface tension of an ink. For this reason, it is possible to detect with a small error that the light shielding plate 60 moves smoothly with a change in the ink remaining amount and the ink remaining amount in the ink chamber 31 reaches a predetermined amount.

  Next, a third embodiment will be described with reference to the drawings. In the third embodiment, members substantially the same as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted.

  As shown in FIG. 13, the shutter mechanism 23B is provided in a space below the ink chamber 31, and includes a light shielding plate 60B that does not transmit light, a hollow float 61, a light shielding plate 60B, and a float 61. A connecting member 62B to be connected, a support base 63 provided on the upper side of the partition wall 30 to rotatably support the connecting member 62B, and a prevention wall 67 for preventing the connecting member 62B from rolling. The light shielding plate 60B, the float 61, and the connecting member 62B constitute a displacement member. The float 61 is a cylindrical member having a sealed space filled with air inside, and the specific gravity of the entire float 61 is smaller than the specific gravity of the ink in the ink chamber 31. The light shielding plate 60B and the float 61 are provided at both ends of the connecting member 62B. At the center of the connecting member 62B, a cylindrical rotating shaft 62aB projecting in a direction perpendicular to the plane of the connecting member 62B is formed, and the support base 63 rotatably supports the rotating shaft 62aB. Yes. The prevention wall 67 is disposed between the rotation shaft 62a and the vertical wall surface 69 so as to extend in the vertical direction from the bottom surface of the ink chamber 31 and to sandwich the connecting member 62B between the planes 2. One wall.

  The light shielding plate 60B is a thin plate-like member that is parallel to the vertical surface and has a predetermined area. The light shielding plate 60B has a rectangular region and a triangular projecting region formed so as to extend further upward from the upper end of the rectangular region. Abutting portions 60a each having a columnar shape protruding in the vertical direction (direction along the ink surface) from the light shielding plate 60B toward the rib 57 are formed on both surfaces of the protruding region.

  On both surfaces of the connecting member 62B in the vicinity of the rotation shaft 62aB, a pin (convex portion) 59B having a column shape protruding in the vertical direction toward the plane of the prevention wall 67 is formed. The tip of the pin 59B has a curved surface. The tip of the pin 59B always faces the prevention wall 67 in a range in which the contact portion 60a moves between a position where the contact portion 60a contacts the contacted surface 56 and a position separated from the contacted surface 56. It has become.

  According to the third embodiment described above, since the distance between the light shielding plate 60B and the inner wall surface 34b is maintained by the pin 59B, the light shielding plate 60B and the inner wall surface 34b are prevented from being bonded due to the surface tension of the ink. can do. For this reason, it is possible to detect with a small error that the light shielding plate 60B smoothly moves with the change in the ink remaining amount and the ink remaining amount in the ink chamber 31 has reached a predetermined amount. Further, since the plane of the pin 59B and the prevention wall 67 facing the pin 59B is formed in the vicinity of the rotation shaft 62aB, the displacement range of the pin 59B is narrowed, and the prevention wall 67 facing the pin 59B is made smaller. Can do.

  Although the embodiments of the present invention have been described above, 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. For example, in the first embodiment, the light shielding plate 60 is arranged to be displaced between the two inner wall surfaces 34b, but the light shielding plate 60 is displaced along one inner wall surface. The structure arrange | positioned may be sufficient. In this case, the pin may be formed so as to protrude toward one inner wall surface.

  In the first embodiment, the light shielding plate 60 has a thin plate shape, but the light shielding plate 60 may have another shape such as a spherical shape.

  Furthermore, in the first embodiment, the ribs 57 and 58 are provided, but a configuration without such ribs is also possible.

  Further, in the present embodiment, the tips of the pins 59 and 59B are formed of curved portions, but the tip shape is not particularly limited, and the pins 59 and 59B and the inner wall surface 34b or the prevention wall 67 are assumed. Even if ink may remain between the two flat surfaces, the tip shape may be sharp or flat if the amount that does not impair the smoothness of the displacement of the displacement member remains. May be.

  In the first embodiment, the contact portion 60a is columnar, but the shape of the contact portion 60a is not limited, and may be, for example, a plate shape. In addition, although the abutted surface 56 is a slope, the abutted surface may be a horizontal plane.

  Furthermore, in the first embodiment, the displacement member rotates about the rotation shaft 62a as the ink amount in the ink chamber 31 increases or decreases. However, the configuration is limited to such a configuration. is not. For example, the displacement member may be composed of a light shielding plate and a float directly connected thereto, and the displacement member may be displaced so as to follow the displacement of the ink liquid level as the amount of ink in the ink chamber increases or decreases.

  Further, in the second embodiment, the rib 58A is formed along the displacement trajectory of the light shielding plate 60. However, the ink is prevented from being held between the light shielding plate 60 and the inner wall surface 34b as much as possible. From the viewpoint of enabling the smooth displacement member to rotate, it is preferable to form the riff 58A along the displacement trajectory of the pin 59.

1 is a schematic configuration diagram of an inkjet printer according to a first embodiment. 2A and 2B are diagrams illustrating the ink cartridge depicted in FIG. 1, in which FIG. 1A is a plan view, FIG. 1B is a left side view, and FIG. FIG. 2 is a perspective view of the ink cartridge depicted in FIG. 1 as viewed from below. It is the IV-IV sectional view taken on the line of FIG. It is a perspective view of the VV line section of Drawing 2 (a). It is a top view of the VV line cross section of Fig.2 (a). It is a front view of the VV line cross section of Fig.2 (a). (A) is a sectional view taken along line VIIIA-VIIIA in FIG. 6, (b) is a sectional view taken along line VIIIB-VIIIB in FIG. 6, and (c) is a sectional view taken along line VIIIC-VIIIC in FIG. FIG. 5 is a cross-sectional view of the ink supply valve depicted in FIG. 4, where (a) is a closed state and (b) is a opened state. FIG. 6 is a perspective view of the valve body depicted in FIG. 5. 3 is a flowchart of a mounting state determination process when the ink cartridge illustrated in FIG. 1 is attached / detached. FIG. 6 is an enlarged view of a partial cross section of an ink cartridge according to a second embodiment. It is a perspective view of the partial cross section of the ink cartridge which concerns on 3rd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 3 Ink cartridge 14 Sensor 14a Light emission part 14b Light reception part 20 Cartridge main body 31 Ink chamber 34 Protrusion part 34a Recess 34b Inner wall surface 56 Contact surface 57, 58 Rib 59 Pin 60 Light-shielding plate 60a Contact part 61 Float 62 Connection Member 66 rib

Claims (12)

An ink tank for storing ink, the ink tank having a downwardly inclined inner surface extending in a downwardly inclined direction with respect to the ink surface;
A displacement member that displaces in the ink tank as the amount of ink stored in the ink tank increases or decreases;
A regulating surface that regulates the displacement of the displacement member,
The displacement member is formed with a contact portion that can selectively take a position that contacts the restriction surface and a position that is separated from the restriction surface according to the position of the displacement member,
A portion of the displacement member that faces the lower inclined inner surface is a convex that always faces the lower inclined inner surface while the contact portion moves between the separated position and the contact position. An ink cartridge in which a portion is formed. The ink tank has two concave portions facing the lower inclined inner surface,
At least a portion of the displacement member is sandwiched between the two downwardly inclined inner surfaces facing each other in the recess, and
2. The ink cartridge according to claim 1, wherein the convex portions protrude from the portions of the displacement member facing the two downwardly inclined inner surfaces toward the downwardly inclined inner surfaces. The displacement member is formed with a thin plate-like portion sandwiched between the two downwardly inclined inner surfaces facing each other in the concave portion when the contact portion is in the contacted position.
The ink cartridge according to claim 2, wherein the convex portion protrudes from the thin plate-shaped portion.   The ink cartridge according to any one of claims 1 to 3, wherein a rib protrudes from a portion of the two downwardly inclined inner surfaces facing the displacement member toward the displacement member. .   The ink cartridge according to claim 4, wherein the rib is provided continuously along a displacement track of the displacement member.   The ink cartridge according to any one of claims 1 to 5, wherein a tip portion of the convex portion is formed by a curved surface protruding toward the downward inclined inner surface. The contact portion is a columnar protrusion extending along the ink surface,
The wall intersecting with the restriction surface is erected in the vicinity in the extending direction of the contact portion when the contact portion contacts at least the restriction surface. The ink cartridge according to any one of -6.   The ink cartridge according to claim 1, wherein the regulation surface is an inclined surface that intersects the ink surface.   The displacement member rotates in the ink tank about an axis perpendicular to the displacement direction of the ink surface as the ink is used as the amount of ink stored in the ink tank increases or decreases. The ink cartridge according to any one of claims 1 to 8.   The ink cartridge according to claim 1, wherein the convex portion and the downward inclined inner surface facing the convex portion are formed in the vicinity of an end portion of the displacement member.   The ink cartridge according to claim 1, wherein the convex portion and the downward inclined inner surface facing the convex portion are formed in the vicinity of the shaft of the displacement member. An ink tank that stores ink, and extends in a direction that is substantially perpendicular to the direction of displacement of the ink surface that accompanies use of the ink, and in a direction that is inclined downward from one end of the restriction surface with respect to the restriction surface An ink tank having a downwardly inclined inner surface;
A displacement member that displaces in the ink tank as the amount of ink stored in the ink tank increases or decreases,
The displacement member is formed with a contact portion that can selectively take a position that contacts the restriction surface and a position that is separated from the restriction surface according to the position of the displacement member,
On the inner wall of the ink tank, two concave portions facing the lower inclined inner surface are formed,
At least a portion of the displacement member is sandwiched between the two downwardly inclined inner surfaces facing each other in the recess,
A convex portion that always faces each downwardly inclined inner surface from a portion of the displacement member that faces the downwardly inclined inner surface while the contact portion moves between the separated position and the abutting position. Each projecting toward the downwardly inclined inner surface, and
An ink cartridge, wherein ribs protrude from the portions of the two downwardly inclined inner surfaces facing the displacement member toward the displacement member.

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