Ink tank

Abstract

The present invention provides an ink tank that reduces the deviation of the detected liquid level position even in a tilted state. The ink tank (18) comprises: an ink storage section (121) that stores ink; a detection section (60) that detects the position of the liquid level (L) of the ink in the ink storage section (121); a supply section (115) that supplies the ink to the outside; and a filter section (113) that is arranged in the ink storage section (121) and between the ink storage section (121) and the supply section (115), wherein the filter section (113) is arranged in the -Z direction relative to the detection section (60) in a perspective observation from the side (129), and the detection section (60) is arranged at the center of the ink storage section (121) in the direction of the Y axis orthogonal to the -Z direction.

Description

Technical Field

[0001] The present invention relates to an ink tank. Background Art

[0002] Inkjet printers are known that eject ink from an inkjet head to perform printing. The ink is stored in a container such as an ink tank mounted on the inkjet printer. For example, Patent Document 1 discloses an ink tank that allows a user to replenish the ink and detect the liquid level of the stored ink.

[0003] Then, in the ink tank described in Patent Document 1, there is a problem that if the inkjet printer is set in a tilted state, the detected liquid level is prone to deviation. Specifically, a pair of conductive components are provided as sensors for the liquid level. The positions of the ends of the pair of conductive components in the vertical direction are different. If the inkjet printer is tilted, the liquid level in the ink tank is also tilted. Therefore, there is a possibility that the positional relationship between the liquid level position and the ends of the pair of conductive components changes, thereby obtaining a detection result different from the original liquid level position. That is, an ink tank is sought that reduces the deviation of the detected liquid level position even when the inkjet printer is in a tilted state.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2016-175294 Summary of the invention

[0005] The ink tank comprises: an ink containing portion for containing ink; a detecting portion for detecting the position of the liquid level of the ink in the ink containing portion; a supply portion for supplying the ink to the outside; and a filter portion arranged in the ink containing portion and between the ink containing portion and the supply portion, wherein the filter portion is arranged in a first direction relative to the detecting portion in a perspective observation from the side, and the detecting portion is arranged at a central portion of the ink containing portion in a second direction orthogonal to the first direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a perspective view showing the structure of an inkjet printer equipped with the ink tank according to the first embodiment.

[0007] Figure 2 It is a schematic perspective view showing the structure of the ink tank.

[0008] Figure 3 It is a schematic perspective view showing the structure of the ink tank.

[0009] Figure 4 It is a schematic cross-sectional view showing the structure of the detection unit.

[0010] Figure 5 It is a schematic perspective view showing the structure of an ink tank according to the second embodiment.

[0011] Figure 6 It is a schematic perspective view of the ink tank of the embodiment.

[0012] Figure 7 It is a schematic perspective view of the ink tank of the embodiment.

[0013] Figure 8 It is a schematic perspective view of an ink tank of a comparative example.

[0014] Fig. 9 It is a schematic perspective view of an ink tank of a comparative example.

[0015] Fig.10 It is a schematic perspective view of an ink tank of a comparative example.

[0016] Fig.11 It is a schematic perspective view of an ink tank of a comparative example.

[0017] Fig.12 It is a schematic perspective view of an ink tank of a comparative example.

[0018] Fig.13A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0019] Fig. 13B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0020] Fig.14A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0021] Fig. 14B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0022] Fig.15A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0023] Fig. 15B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0024] Fig.16A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0025] Fig. 16B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0026] Fig.17AThis is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0027] Fig. 17B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0028] Fig.18A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0029] Fig.18B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0030] Fig.19A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0031] Fig.19B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0032] Fig. 20A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0033] Fig. 20B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0034] Fig.21A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0035] Fig. 21B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0036] Fig.22A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0037] Fig. 22B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0038] Fig.23A This is a schematic perspective view showing the liquid level of ink in a tilted ink tank.

[0039] Fig. 23B This is a schematic perspective view showing the liquid level of ink in a tilted ink tank. DETAILED DESCRIPTION

[0040] In the embodiments described below, an ink tank mounted on an inkjet printer is exemplified and described with reference to the accompanying drawings. In addition, an inkjet printer equipped with the ink tank of the present invention is not limited to a non-carriage-mounted type. In addition, there is sometimes a case where an inkjet printer is simply referred to as a printer.

[0041] In the following figures, as required, XYZ axes are marked as mutually orthogonal coordinate axes, and the direction indicated by each arrow mark is set as the + direction, and the direction opposite to the + direction is set as the - direction. When the ink tank of the present invention is installed on a horizontal plane, the first direction is consistent with the vertical direction, and the second direction orthogonal to the first direction is consistent with the horizontal direction. In the above case, specifically, the -Z direction is the first direction, and the direction along the Y axis is the second direction. In addition, for the convenience of illustration, the size of each component is different from the actual size.

[0042] 1. First Implementation

[0043] The printer 1 equipped with the ink tank 18 according to the present embodiment is a printing device that performs printing by causing ink droplets to adhere to a printing medium such as paper.

[0044] like Figure 1 As shown, the printer 1 has a substantially rectangular outer casing 20. An operation panel 17 and a tank unit 19 are arranged on the surface of the outer casing 20 facing the -Y direction. The operation panel 17 has an operation unit 15 and a display unit 16. The operation unit 15 is provided with buttons for performing various operations through the printer 1. The display unit 16 displays various information of the printer 1. The display unit 16 is, for example, a liquid crystal panel. The operation panel 17 and the display unit 16 can also be integrally configured as a touch panel. In addition, the printer 1 has a control unit not shown in the figure. The control unit performs unified control over the operation of the printer 1.

[0045] The tank unit 19 accommodates five ink tanks 18a, 18b, 18c, 18d, and 18e. The ink tanks 18a, 18b, 18c, 18d, and 18e are sometimes collectively referred to as ink tanks 18. Although not shown in the figure, the ink tanks 18 contain ink to be supplied to the printer 1 for printing.

[0046] The printer 1 can replenish the ink by allowing the user to inject ink from the ink storage container into the ink tank 18 when the ink storage amount of the ink tank 18 is reduced. In addition, the ink tank 18 is not limited to a method of replenishing ink, and the ink tank 18 may be replaced. In addition, the number of ink tanks 18 is not limited to five.

[0047] When ink is replenished from the ink storage container to the ink tank 18, the image reader 13 above the outer housing 20 and the cover 29 above the tank unit 19 are respectively flipped up in the +Z direction. Thus, the inlet (not shown) of the ink tank 18 is opened in the +Z direction, and ink can be replenished.

[0048] The ink tank 18 may contain five inks of different colors or inks of the same color. The five inks may include a transparent ink or a treatment liquid such as a coating liquid.

[0049] Five windows 21 are provided on the front surface 99 of the tank unit 19 at positions corresponding to the ink tanks 18. Each window 21 is a through hole provided in the outer casing 20. Through each window 21, the ink visual confirmation portion 61 of the corresponding ink tank 18 can be visually confirmed.

[0050] The ink visual confirmation portion 61 is a part of the wall of the housing of the ink tank 18. Through the ink visual confirmation portion 61, the ink storage portion described later in the ink tank 18 can be visually confirmed. Thus, the user can grasp the approximate amount of ink stored in the ink tank 18.

[0051] The outer housing 20 contains a printing unit 23 that prints by attaching ink to a printing medium. The printing unit 23 includes an ink pipe 24, an inkjet head 25, and a carriage 26. The ink pipe 24 includes a plurality of pipes that individually supply each ink contained in the ink tank 18 to the inkjet head 25. Figure 1 In the figure, for the convenience of illustration, the ink pipe 24 is set as one pipe.

[0052] The inkjet head 25 is arranged in the -Z direction of the carriage 26. Ink is supplied to the inkjet head 25 from the ink tank 18 via the ink pipe 24. Although not shown in the figure, the inkjet head 25 has an actuator as a driving means and a plurality of nozzle arrays facing the -Z direction. In the inkjet head 25, the corresponding ink is ejected as ink droplets from the plurality of nozzles of each nozzle array by driving the actuator.

[0053] Examples of the actuator of the inkjet head 25 include a piezoelectric element, an electromechanical transducer element that displaces a vibration plate by electrostatic adsorption, and a thermoelectric transducer element that ejects ink droplets by utilizing bubbles generated by heating.

[0054] The carriage 26 can reciprocate in the direction along the X-axis by a driving unit (not shown). Although not shown in the figure, the printer 1 includes a conveying unit that conveys the print medium in the -Y direction relative to the carriage 26. Therefore, the inkjet head 25 can scan in the direction along the X-axis and move in the direction along the Y-axis relative to the print medium. By conveying the print medium while the inkjet head 25 is scanning, and controlling the color type of ink, the number or quality of ink droplets, and the timing of ejection, etc., a color image can be printed on the print medium.

[0055] like Figure 2 As shown in FIG. 1 , the ink tank 18 includes an inlet 111, an ink storage portion 121, a detection portion 60, a visual confirmation portion 61, a filter portion 113, and a supply portion 115. Figure 2 In FIG. 1 , the ink flow path from the filter unit 113 to the supply unit 115 is omitted from illustration.

[0056] The housing of the ink tank 18 is a substantially cubic shape. The ink tank 18 has a pair of side surfaces 129 facing each other in the direction along the X-axis, a pair of side surfaces 128 facing each other in the direction along the Y-axis, and an upper surface 127 and a bottom surface 126 facing each other in the direction along the Z-axis. The length of the side surface 129 along the Y-axis is longer than the length of the side surface 128 along the X-axis. When the printer 1 is placed on a horizontal plane, the -Z direction coincides with the vertical direction, and in the ink tank 18 mounted on the printer 1, the upper surface 127 and the bottom surface 126 are along the horizontal plane.

[0057] As the material of the ink tank 18, for example, resins such as polyolefin, polycarbonate, and polyester are used. Preferably, the material of the ink tank 18 does not deteriorate or dissolve due to the contained ink. In addition, the ink tank 18 may be partially formed of a material such as a resin film, glass, or metal. In addition, when a microstrip antenna method described later is adopted in the detection unit 60, a dielectric such as resin is mainly used as the material of the ink tank 18.

[0058] The ink container 121 is provided inside the housing of the ink tank 18. Ink is contained in the ink container 121. In the present embodiment, the ink container 121 is formed into a substantially cubic space, but the shape of the ink container 121 is not limited thereto. The ink container 121 may also have partitions, partitions, flow channels, valves, and the like.

[0059] The filter unit 113 is disposed on the surface along the bottom surface 126 of the ink container 121. The filter unit 113 includes, for example, a metal mesh, etc. The filter unit 113 is interposed between the ink container 121 and the supply unit 115, and captures foreign matter and the like contained in the ink contained in the ink container 121.

[0060] The supply unit 115 is arranged in the +Y direction of the bottom surface 126 and is protruded in the -Z direction. The supply unit 115 supplies the ink stored in the ink storage unit 121 to the outside of the ink tank 18. The ink is supplied from the ink storage unit 121 to the ink pipe 24 through the filter unit 113 and the supply unit 115.

[0061] When the printer 1 is installed on a horizontal plane, the detection unit 60 is disposed on the side surface 129 that is longer in the horizontal direction, that is, along the Y axis, of the side surfaces 128 and 129 intersecting the horizontal plane. This makes it easy to secure a space for arranging the detection unit 60.

[0062] When the printer 1 is placed on a horizontal surface, the detection unit 60 is arranged at the center of the ink container 121 in the direction along the Y axis as the second direction when viewed from the side 129. In addition, in the above-mentioned perspective view, the filter unit 113 is arranged in the -Z direction as the first direction relative to the detection unit 60.

[0063] The central portion of the ink container 121 refers to the central region of the ink container 121 in the direction along the Y axis when viewed from the side from the -X direction. Therefore, "arranged in the central portion of the ink container 121" means that the center line of the detection unit 60 along the Z axis in the direction along the Y axis is closer to the center line of the ink container 121 along the Z axis in the direction along the Y axis than the side surface 128 of the ink container 121.

[0064] When the printer 1 is tilted, the ink tank 18 is tilted in the rotation direction with the straight line along the X-axis as the rotation axis, tilted in the rotation direction with the straight line along the Y-axis as the rotation axis, and tilted in the rotation direction with the straight line on the XY plane and intersecting the X-axis and the Y-axis as the rotation axis. Among these tilts, when viewed from the perspective of the direction along the rotation axis, the increase in the deviation of the liquid surface of the ink caused by the tilt refers to the tilt in the rotation direction with the straight line along the X-axis as the rotation axis. That is, the deviation of the detected liquid surface position has always increased in the tilt in the rotation direction with the straight line along the X-axis as the rotation axis. Therefore, in this specification, the tilt in the rotation direction with the straight line along the X-axis as the rotation axis is described.

[0065] The detection unit 60 detects the position of the ink surface in the ink container 121. The detection unit 60 includes receiving electrodes 131 and 133 and a transmitting electrode described below. The receiving electrodes 131 and 133 are arranged on the side surface 129 in the -X direction of the ink tank 18. The transmitting electrode is arranged on the side surface 129 in the +X direction.

[0066] The receiving electrodes 131 and 133 are provided on the housing of the ink tank 18. The receiving electrodes 131 and 133 are substantially rectangular in the long-side direction along the Y axis in the side view observed from the -X direction. In the side view observed from the -X direction, the receiving electrode 131 is arranged near the upper surface 127, and the receiving electrode 133 is arranged near the bottom surface 126.

[0067] The receiving electrode 131 detects that the ink storage volume in the ink storage section 121 is sufficient. The receiving electrode 133 detects that the ink storage volume is insufficient. In addition, other receiving electrodes may be arranged between the receiving electrodes 131 and 133 in the direction along the Z axis.

[0068] The ink container 121 has an injection port 111 on its upper surface 127. Specifically, when the printer 1 equipped with the ink tank 18 is placed on a horizontal surface, the injection port 111 is arranged at one end portion relative to the central portion in the direction along the Y axis. Specifically, the injection port 111 is arranged at a side surface 128 in the -Y direction relative to the ink container 121 and in the +Z direction in a side view from the -X direction.

[0069] The injection port 111 is, for example, a tubular member, and the top end in the +Z direction protrudes from the upper surface 127, and the top end in the -Z direction communicates with the inside of the ink container 121. The ink can be replenished into the ink container 121 through the injection port 111. Since the injection port 111 is arranged on the upper surface 127, the ink can be injected into the ink container 121 from the injection port 111 by gravity. The injection port 111 may have a cap or the like at the top end in the +Z direction.

[0070] The ink tank 18 is provided with a visual confirmation portion 61. When the printer 1 equipped with the ink tank 18 is placed on a horizontal surface, the visual confirmation portion 61 is arranged at one end portion of the ink tank 18 relative to the central portion in the direction along the Y axis which is the horizontal direction. Specifically, the visual confirmation portion 61 is arranged on the side surface 128 in the -Y direction.

[0071] The visual confirmation portion 61 is made of a light-transmitting material such as resin or glass. The liquid level of the ink in the ink container 121 can be visually confirmed through the visual confirmation portion 61. The visual confirmation portion 61 can be made of, for example, a translucent resin as long as the liquid level can be visually confirmed.

[0072] like Figure 3 As shown in FIG. 1 , the transmitting electrode 122 is substantially rectangular in a side view from the +X direction. The transmitting electrode 122 is provided on the housing of the ink tank 18 so as to be opposed to the receiving electrodes 131 and 133 in the direction along the X axis. A pulse wave is transmitted from the transmitting electrode 122. The pulse wave is received by the receiving electrodes 131 and 133 via the housing of the ink tank 18 and the ink storage portion 121. Details of the detection unit 60 including the receiving electrodes 131 and 133 and the transmitting electrode 122 will be described below.

[0073] like Figure 4 As shown in the figure, the detection unit 60 includes a transmitting electrode 122, receiving electrodes 131 and 133, and a processing unit (not shown). The detection unit 60 detects the position of the liquid level of the ink in the ink storage unit 121, that is, the ink storage amount. When the ink tank 18 is mounted on the printer 1, the processing unit is electrically connected to the control unit of the printer 1 via wiring (not shown).

[0074] As a method for detecting the ink storage amount, there are known liquid level sensors such as optical, float, microstrip antenna, and ultrasonic. Although in this embodiment, a detection method realized by a microstrip antenna method is used as a liquid level sensor, it is not limited to this.

[0075] The transmitting electrode 122 and the receiving electrodes 131 and 133 are arranged to face each other in the direction along the X axis with the ink tank 18 interposed therebetween. The transmitting electrode 122 and the receiving electrodes 131 and 133 are made of a conductive material such as a metal such as gold, silver, copper, aluminum, or iron, or an alloy.

[0076] The receiving electrodes 131 and 133 are provided at positions overlapping the transmitting electrode 122 in perspective observation from the -X direction. The receiving electrode 133 and the receiving electrode 131 are arranged in this order from the bottom surface 126 side toward the +Z direction. The receiving electrode 131 is arranged at a height position H1, and the receiving electrode 133 is arranged at a height position H3.

[0077] The transmission electrode 122 and the reception electrode 131 are parallel flat plates facing each other, and form a capacitor 171. Similar to the capacitor 171, the transmission electrode 122 and the reception electrode 133 form a capacitor 173.

[0078] The electrostatic capacitance of the capacitors 171 and 173 is determined by the dielectric constant of the substance interposed between the electrodes of the capacitors 171 and 173. The dielectric constant of air is substantially zero, and the dielectric constant of ink is greater than that of air.

[0079] The transmission electrode 122 is electrically connected to an AC power source 144 via a switch circuit 142. The AC power source 144 outputs a pulse wave as a transmission signal to the transmission electrode 122. The pulse wave passes through the air or ink in the ink tank 18 in the capacitors 171 and 173 and is received by the reception electrodes 131 and 133.

[0080] The receiving electrode 131 is electrically connected to the processing unit (not shown) via the wiring 141, and the receiving electrode 133 is electrically connected to the processing unit via the wiring 143. The processing unit includes, for example, a processing circuit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), and a storage circuit such as a semiconductor memory.

[0081] In the direction along the Z axis, the liquid level LV1 is the range from the lower end to the upper end of the capacitor 171, and the liquid level LV3 is the range from the lower end to the upper end of the capacitor 173. From the bottom surface 126 of the ink tank 18 toward the +Z direction, the liquid level LV3 and the liquid level LV1 are arranged in this order.

[0082] When the liquid surface L of the ink exists in any of the liquid surface levels LV1 and LV3, a difference will occur in the pulse wave received by the receiving electrodes 131 and 133, in other words, in the output voltage of the capacitors 171 and 173. Within the corresponding range, this output voltage becomes larger when ink exists, becomes smaller when air exists, and becomes a roughly intermediate value when ink and air exist. The output voltages in these cases are pre-set as three thresholds. That is, by comparing the output voltages of the capacitors 171 and 173 with the three thresholds in the processing unit, the position of the liquid surface L can be specifically specified. In this way, the amount of ink stored in the ink tank 18 can be detected.

[0083] The detection unit 60 is electrically connected to the control unit of the printer 1. The detection unit 60 sends the ink storage amount in the ink storage unit 121 as a detection result to the control unit. The control unit controls various operations of the printer 1 based on the ink storage amount. Examples of the various operations include the number or quality of ink droplets ejected from the inkjet head 25, maintenance conditions related to the inkjet head 25, and the like.

[0084] Furthermore, the control unit may display the ink storage amount on the display unit 16 or an information device that operates the printer 1. The control unit may also notify the user, via the display unit 16, that the ink is insufficient and needs to be replenished, or that the ink is sufficient. In addition, the control unit of the printer 1 may assume the function of the processing unit of the detection unit 60.

[0085] According to this embodiment, the following effects can be obtained.

[0086] Even if the printer 1 is in a tilted state, the deviation of the detected ink liquid level position can be reduced. Specifically, if the printer 1 is set in a tilted posture, the ink tank 18 is also tilted, so that the liquid level L of the ink in the ink storage section 121 is tilted. For example, in a side view observed from the -X direction, when the +Y direction of the printer 1 is set higher and the -Y direction is set lower, the liquid level L becomes higher at the end of the ink storage section 121 in the -Y direction, and the liquid level L becomes lower at the end of the +Y direction. In addition, if the printer is set in a manner opposite to the above, the liquid level L becomes lower at the end of the -Y direction of the ink storage section 121, and the liquid level L becomes higher at the end of the +Y direction. In this way, at the end of the ink storage section 121, a deviation in the liquid level L occurs due to the tilt of the mounted printer 1.

[0087] On the other hand, at the center of the ink container 121, even if the printer 1 is tilted, the liquid level L is unlikely to change. Therefore, in the detection unit 60 disposed at the center of the ink container 121, the detected liquid level position is unlikely to vary. Thus, it is possible to provide an ink tank 18 in which the variation of the detected liquid level position is reduced with respect to the installation posture of the printer 1.

[0088] Since the filter unit 113 and the detection unit 60 are arranged along the Z axis, the distance between them is shortened. Therefore, compared with the case where the filter unit 113 and the detection unit 60 are arranged separately, the state where the amount of ink remaining exposed from the liquid surface L of the ink by the filter unit 113 is extremely small can be detected with high accuracy.

[0089] Since the visual confirmation section 61 is provided, the position of the ink liquid level in the ink container 121 can be visually confirmed. In addition, when the ink is replenished into the ink container 121 while the ink liquid level L is visually confirmed by the visual confirmation section 61, excessive ink injection can be suppressed.

[0090] In detail, when the printer 1 is set in the above-mentioned posture, the liquid surface L of the ink in the ink storage section 121 is inclined. At this time, since the visual confirmation section 61 and the injection port 111 are both arranged at the end of the ink storage section 121 in the -Y direction, there is a correlation between the liquid surface position of the ink visually confirmed by the visual confirmation section 61 and the amount of ink that can be replenished to the ink storage section 121. Therefore, by increasing or decreasing the amount of ink to be replenished according to the visually confirmed liquid surface position, excessive replenishment of ink can be avoided. As a result, it is possible to suppress excessive injection of ink, thereby preventing the ink from overflowing from the ink tank 18.

[0091] 2. Second Implementation

[0092] The ink tank according to this embodiment is mounted on the printer 1 in the same manner as the ink tank 18 according to the first embodiment.

[0093] like Figure 5 As shown in the figure, the ink tank 28 according to the present embodiment includes an injection port 211, an ink storage portion 121, a detection portion 60, a visual confirmation portion 61, a filter portion 113, and a supply portion 115. The housing of the ink tank 28 is a substantially cubic shape. Figure 5 In FIG. 1 , the ink flow path from the filter unit 113 to the supply unit 115 is omitted from illustration.

[0094] The ink tank 28 has a different arrangement of the injection port 211 than the ink tank 18 of the first embodiment. In the following description, the same reference numerals are used for the same components as those of the first embodiment, and duplicate descriptions are omitted.

[0095] The top surface 127 of the ink container 121 is provided with an injection port 211. Specifically, the injection port 211 is arranged in the +Z direction of the detection unit 60. In other words, when the printer 1 equipped with the ink tank 28 is arranged on a horizontal surface, the injection port 211 is arranged in a direction opposite to the vertical direction as the first direction with respect to the detection unit 60.

[0096] The injection port 211 is, for example, a tubular member, and its top end in the +Z direction protrudes from the upper surface 127, and its top end in the -Z direction communicates with the inside of the ink container 121. The ink is replenished into the ink container 121 through the injection port 211. Since the injection port 211 is arranged on the upper surface 127, the ink can be injected from the injection port 211 into the ink container 121 by gravity. The injection port 211 may have a cap or the like at the top end in the +Z direction.

[0097] According to the present embodiment, in addition to the effects of the first embodiment, the following effects can be obtained.

[0098] The detected ink storage amount can be used to prevent the user from overfilling the ink into the ink storage section 121. Specifically, when the printer 1 is set in an inclined posture, the ink tank 28 is also inclined, and the liquid level L of the ink in the ink storage section 121 is inclined. At this time, the liquid level position of the ink is unlikely to change at the center of the ink storage section 121 along the Y-axis direction, and the liquid level position detected by the detection unit 60 is unlikely to deviate.

[0099] Furthermore, since the injection port 211 is arranged in the +Z direction of the central portion of the ink container 121, there is a correlation between the detected ink storage amount and the amount of ink that can be replenished to the ink container 121. Therefore, by increasing or decreasing the amount of ink to be replenished according to the ink storage amount, excessive replenishment of ink can be avoided. Thus, excessive injection of ink can be suppressed, thereby preventing the ink from the ink tank 28 from overflowing.

[0100] 3. Example

[0101] The effects of the above-described embodiment will be described more specifically by way of examples. As examples, the ink tank 18 of the first embodiment and the ink tank 28 of the second embodiment are exemplified. As comparative examples, ink tanks 38, 48, 58, 68, and 78 are exemplified.

[0102] like Figure 6 As shown, in the ink tank 18, the detection section 60 is arranged at the center of the ink container 121 along the Y axis direction. The filter section 113 is arranged in the -Z direction of the detection section 60. The injection port 111 is arranged in the -Y direction and the +Z direction of the ink container 121. The visual confirmation section 61 is arranged in the -Y direction of the housing of the ink tank 18.

[0103] like Figure 7 As shown, in the ink tank 28, the detection section 60 is arranged at the center of the ink storage section 121 along the Y axis. The filter section 113 is arranged in the -Z direction of the detection section 60. The injection port 211 is arranged in the +Z direction of the detection section 60. The visual confirmation section 61 is arranged in the -Y direction of the housing of the ink tank 28.

[0104] like Figure 8 As shown, in the ink tank 38, the detection section 60 is arranged at the end of the ink storage section 121 in the -Y direction. The filter section 113 is arranged in the -Z direction of the detection section 60. The injection port 111 is arranged in the +Z direction of the detection section 60. The visual confirmation section 61 is arranged in the -Y direction of the housing of the ink tank 38.

[0105] like Fig. 9As shown in the figure, in the ink tank 48, the detection unit 60 is arranged at the end of the ink storage unit 121 in the -Y direction. The filter unit 113 is arranged in the -Z direction of the detection unit 60. In the ink storage unit 121, the injection port 211 is arranged in the +Z direction of the central part along the direction of the Y axis. The visual confirmation unit 61 is arranged in the -Y direction of the housing of the ink tank 48.

[0106] like Fig.10 As shown in FIG. 1 , in the ink tank 58, the detection unit 60 is arranged at the end of the ink container 121 in the -Y direction. The filter unit 113 is arranged at the end of the ink container 121 in the +Y direction and in the -Z direction. The injection port 111 is arranged in the +Z direction of the detection unit 60. The visual confirmation unit 61 is arranged in the -Y direction of the housing of the ink tank 58.

[0107] like Fig.11 As shown in the figure, in the ink tank 68, the detection section 60 is arranged at the end of the ink storage section 121 in the -Y direction. The filter section 113 is arranged in the -Z direction of the detection section 60. The injection port 111 is arranged in the +Y direction and in the +Z direction of the ink storage section 121. The visual confirmation section 61 is arranged in the -Y direction of the housing of the ink tank 68.

[0108] like Fig.12 As shown in the figure, in the ink tank 78, the detection unit 60 is arranged at the end of the ink storage unit 121 in the +Y direction. The filter unit 113 is arranged in the -Z direction of the detection unit 60. The injection port 111 is arranged in the -Y direction and in the +Z direction of the ink storage unit 121. The visual confirmation unit 61 is arranged in the -Y direction of the housing of the ink tank 78. That is, in the perspective observation observed from the -X direction, in the direction along the Y axis of the ink storage unit 121, the detection unit 60 and the filter unit 113 are arranged at the end of the +Y direction, and the injection port 111 and the visual confirmation unit 61 are arranged at the end of the -Y direction.

[0109] Here, in Figures 6 to 12 In the figure, when the printer 1 is placed on a horizontal surface, in the ink container 121, the area detected as having sufficient ink is area b, and the area detected as having no ink is area c. Area a is a range where ink can be further added after the detection unit 60 detects that there is sufficient ink. When the printer 1 is placed on a horizontal surface, areas a, b, and c are the same in the ink tank 18 to the ink tank 78. Figures 6 to 12 In the figure, structures other than the above structures are omitted.

[0110] The following describes the influence of the tilt in the rotation direction with the straight line along the above-mentioned X-axis as the rotation axis for the ink tanks 18 to 78. In the drawings to be referred to later, the figures with A added to the end of the figure number represent the state in which the above-mentioned rotation direction is counterclockwise rotation and the end in the -Y direction is lifted up in the side view from the -X direction. In addition, the figures with B added to the end of the figure number represent the state in which the above-mentioned rotation direction is clockwise rotation and the end in the +Y direction is lifted up in the side view from the -X direction.

[0111] Further, in the drawings referred to below, the Figures 6 to 12 , and a G axis is added to the XYZ axis as another coordinate axis. In the G axis, the direction indicated by the arrow mark coincides with the vertical direction. In the following description, unless otherwise specified, it is assumed that the state of each ink tank being viewed from the -X direction is described.

[0112] 3.1. Configuration of the detection unit and filter unit

[0113] The influence of the inclination on the arrangement of the detection unit 60 and the filter unit 113 will be described.

[0114] When the ink storage amount of the ink storage section 121 decreases, the ink is detected to be out of ink by the detection section 60. At this time, ink still remains in the vertical direction of the detection section 60. This is the area c where the ink remains during the above-mentioned ink out detection. In addition, this area is hereinafter referred to as the ink out detection area c.

[0115] When the detection unit 60 detects that there is no ink, the printer 1 uses the ink in the ink-out detection area c through software control of the control unit. Specifically, the control unit estimates the ink storage amount of the ink storage unit 121 based on the amount of ink droplets ejected by the inkjet head 25 and the amount of ink consumed by cleaning of the inkjet head 25, and continues the operation of the printer 1.

[0116] If the ink in the ink-free detection area c is continuously used, the ink storage amount will become extremely small. If the ink is further used, the filter unit 113 will be exposed to the air. If the filter unit 113 is exposed to the air, the air will flow into the inkjet head 25, which will become the main cause of the failure. Therefore, the control unit will stop the use of the ink in the ink storage unit 121 by leaving a surplus to prevent the filter unit 113 from being exposed to the air.

[0117] Therefore, in order to reduce the amount of unused ink remaining and prevent the filter unit 113 from being exposed to the air, it is necessary to suppress the deviation of the ink storage amount during the ink-out detection caused by the tilt of the printer 1. In the following description, the remaining ink area just before the filter unit 113 is exposed to the air is referred to as the filter exposure pre-area e.

[0118] like Fig.13A as well as Fig. 13B As shown in FIG. 1 , in the ink tanks 18 and 28, the detection unit 60 and the filter unit 113 are both arranged at the center of the ink storage unit 121 along the Y axis. Therefore, the difference between the ink storage amount in the ink-free detection area c1 and the ink storage amount in the ink-free detection area c2 becomes smaller. That is, the detection deviation of the ink storage amount during the ink-free detection is reduced. In addition, the difference between the ink storage amount in the filter exposure front area e1 and the ink storage amount in the filter exposure front area e2 is also reduced.

[0119] like Fig.14A as well as Fig. 14B As shown in the figure, in the ink tanks 38, 48, and 68, the detection unit 60 and the filter unit 113 are both arranged at one end of the ink storage unit 121. Therefore, the difference between the ink storage amount of the ink-free detection area c3 and the ink storage amount of the ink-free detection area c4 becomes larger, and the detection deviation of the ink storage amount during the ink-free detection increases. In addition, the difference between the ink storage amount of the filter-exposed area e3 and the ink storage amount of the filter-exposed area e4 also becomes larger.

[0120] According to the above, by arranging the detection unit 60 and the filter unit 113 at the center along the Y-axis, the detection accuracy of the ink storage amount during the ink-out detection is improved. In addition, since the difference in the ink storage amount between the areas e1 and e2 before the filter is exposed is reduced, the ink remaining as the residual amount in the ink storage unit 121 can be reduced.

[0121] 3.2. Arrangement of the filter unit relative to the detection unit

[0122] The influence of the inclination of the filter unit 113 in the arrangement with respect to the detection unit 60 will be described.

[0123] like Fig.15A as well as Fig. 15B As shown in FIG. 1 , in the ink tank 58, the detection unit 60 is arranged at one end and the filter unit 113 is arranged at the other end in the direction along the Y axis of the ink storage unit 121. Since the detection unit 60 and the filter unit 113 are arranged separately, there is a possibility that the ink storage amount in the ink-out detection area c4 becomes smaller than the ink storage amount in the filter exposure pre-area e6 due to the inclination of the ink tank 58. That is, the filter unit 113 may be exposed earlier than the ink-out detection.

[0124] like Fig.14A as well as Fig. 14B As shown, in the ink tanks 38, 48, and 68, since the detection unit 60 and the filter unit 113 are arranged at the one end, the possibility of the filter unit 113 being exposed earlier than the ink-out detection is reduced. In addition, in the ink tanks 18 and 28 described above, the above possibility is further reduced.

[0125] As described above, by arranging the filter unit 113 in the −Z direction with respect to the detection unit 60 , it is possible to suppress exposure of the filter unit 113 to the air.

[0126] 3.3. Configuration of the detection unit

[0127] The following describes the influence of the inclination in the arrangement of the detection unit 60. Here, the lower limit of the liquid surface level of the region where the detection unit 60 detects that there is sufficient ink in the ink containing portion 121 is defined as Lb.

[0128] like Fig.13A as well as Fig. 13B As shown, in the ink tanks 18 and 28, the detection unit 60 is arranged at the center of the ink container 121 along the Y axis. Therefore, the difference between the liquid level Lb1 and the liquid level Lb2 becomes small. That is, when the ink container 121 has a sufficient amount of ink, the deviation of the detection of the liquid level position is reduced.

[0129] like Fig.14A as well as Fig. 14B As shown, in the ink tanks 38, 48, and 68, the difference between the liquid level Lb3 and the liquid level Lb4 becomes larger because the detection unit 60 is arranged at the end of the ink container 121 along the Y axis. That is, when the ink container 121 has a sufficient amount of ink, the deviation of the detection of the liquid level position increases.

[0130] As described above, by arranging the detection unit 60 at the center of the ink container 121 in the direction along the Y axis, it is possible to improve the detection accuracy of the ink storage amount when the ink storage unit 121 has a sufficient ink storage amount.

[0131] 3.4. Placement of injection port relative to the detection unit

[0132] The influence of the inclination of the injection ports 111 and 211 in the arrangement with respect to the detection unit 60 will be described.

[0133] Even if the ink level is at the level Lb, there is still space in the +Z direction of the ink container 121, so that ink can be further added. At this time, if there is a large difference in the amount of ink that can be added due to the tilt of the printer 1, the ink may be overfilled and overflow.

[0134] like Fig.16A as well as Fig. 16B As shown, in the ink tank 28, the area from the liquid surface Lb1 to the top of the injection port 211 in the -Z direction is defined as area k1, and the area from the liquid surface Lb2 to the top of the injection port 211 in the -Z direction is defined as area k2. That is, if the range of areas k1 and k2 is not exceeded, the ink will not overflow even if the ink is added.

[0135] In the ink tank 28, the detection unit 60 is arranged at the center of the ink container 121 along the Y axis, and the injection port 211 is arranged in the +Z direction of the detection unit 60. Therefore, the difference between the area k1 and the area k2 is reduced. That is, when the ink is added to the ink container 121 beyond the liquid levels Lb1 and Lb2, the occurrence of ink overflow can be suppressed.

[0136] like Fig.17A as well as Fig. 17B As shown, in the ink tank 18, the area from the liquid surface Lb1 to the top of the injection port 111 in the -Z direction is defined as the region k3, and the area from the liquid surface Lb2 to the top of the injection port 111 in the -Z direction is defined as the region k4. If the range of the regions k3 and k4 is not exceeded, the ink will not overflow even if the ink is added.

[0137] In the ink tank 18, in the ink container 121, the detection unit 60 is arranged at the center along the Y axis, and the injection port 111 is arranged in the +Z direction at the end of the -Y direction. The area k4 is smaller than the area k3, and the difference between the area k3 and the area k4 becomes larger. That is, when the ink is injected into the ink container 121 beyond the liquid levels Lb1 and Lb2, the ink is likely to overflow.

[0138] As described above, by arranging the detection unit 60 at the center of the ink container 121 along the Y axis and arranging the injection port 211 in the +Z direction of the detection unit 60 , it is possible to suppress the occurrence of ink overflow when filling the ink.

[0139] 3.5. Configuration of the detection unit and visual confirmation unit

[0140] The influence of the inclination on the arrangement of the detection unit 60 and the visual confirmation unit 61 will be described.

[0141] When the ink storage amount of the ink storage unit 121 decreases, the ink is detected to be out of ink by the detection unit 60. At this time, ink still remains in the vertical direction of the detection unit 60, that is, in the ink out detection area c. The control unit notifies the user of the insufficient ink storage amount of the ink storage unit 121 via the display unit 16 or an information device that operates the printer 1.

[0142] The user may receive the notification and visually check the ink storage amount through the visual confirmation unit 61. In this case, if the visually confirmed ink storage amount varies due to the tilt of the printer 1, the user may be confused.

[0143] like Fig.18A as well as Fig.18B As shown, in the ink tanks 38 , 48 , and 68 , the height of the liquid level visually confirmed corresponding to the ink-free detection area c3 is s1 , and the height of the liquid level visually confirmed corresponding to the ink detection area c4 is s2 .

[0144] Although in Fig.18A and Fig.18B Although the tilt directions are different, the difference between the liquid level s1 and the liquid level s2 is not large because the detection unit 60 and the visual confirmation unit 61 are both arranged at the ends along the Y axis. Therefore, the possibility of confusing the user due to the height of the visually confirmed liquid level is reduced.

[0145] like Fig.19A as well as Fig.19B As shown, in the ink tank 78, the height of the liquid level visually confirmed corresponding to the ink-out detection area c5 is denoted as s0, and the height of the liquid level visually confirmed corresponding to the ink-out detection area c6 is denoted as s3.

[0146] There is a possibility that the liquid level s0 is zero, and the user may think that the ink storage amount is completely gone. On the other hand, there is a possibility that the liquid level s3 is as high as the middle of the visual confirmation section 61, and the user may mistakenly think that the ink storage amount is sufficient contrary to the notification content. This is because the detection section 60 and the visual confirmation section 61 are arranged at different ends in the direction along the Y axis.

[0147] like Fig. 20A as well as Fig. 20B As shown, in the ink tanks 18 and 28 , the height of the liquid level visually confirmed corresponding to the ink-out detection area c1 is s4 , and the height of the liquid level visually confirmed corresponding to the ink-out detection area c2 is s5 .

[0148] There is a possibility that the liquid level s4 is low, so the user thinks that the ink storage amount is small. In contrast, there is also a possibility that the liquid level s5 is high, so the user thinks that the ink storage amount is still sufficient. Although the difference between the liquid level s4 and the liquid level s5 is smaller than the difference between the liquid level s0 and the liquid level s3 described above, it is larger than the difference between the liquid level s1 and the liquid level s2 described above. This is because, in the direction along the Y axis, the detection unit 60 is arranged at the center, and the visual confirmation unit 61 is arranged at the end in the -Y direction.

[0149] As described above, by configuring the detection unit 60 and the visual confirmation unit 61 at the end of the ink storage unit 121 in the -Y direction along the Y axis, it is possible to reduce the deviation of the ink storage amount visually confirmed in the visual confirmation unit 61 when the ink-out state is notified.

[0150] 3.6. Configuration of the detection unit, visual confirmation unit, and injection port

[0151] The influence of the inclination on the arrangement of the detection portion 60 , the visual confirmation portion 61 , and the injection ports 111 , 211 will be described.

[0152] Even if it is detected that the ink storage unit 121 has a sufficient amount of ink, ink can be added while visually checking the ink storage amount through the visual confirmation unit 61. At this time, if there is a large difference in the visually confirmed ink storage amount due to the inclination of the printer 1, the ink may be overfilled and overflow.

[0153] like Fig.21A as well as Fig. 21B As shown, in the ink tanks 38 and 58, the area where ink can be added to the area b3 is set as k5, and the area where ink can be added to the area b4 is set as k6. In addition, the visually confirmed liquid level corresponding to the areas b3 and k5 is set as s6, and the visually confirmed liquid level corresponding to the areas b4 and k6 is set as s7.

[0154] In the ink tanks 38 and 58, the injection port 111, the detection unit 60, and the visual confirmation unit 61 are provided at the end of the ink container 121 in the -Y direction along the Y axis. Therefore, the difference between the liquid level s6 and the liquid level s7 is reduced. That is, the occurrence of ink overflow when the ink is injected into the areas k5 and k6 of the ink container 121 can be suppressed.

[0155] like Fig.22A as well as Fig. 22BAs shown, in the ink tank 48, the area where ink can be added to the area b3 is set as k7, and the area where ink can be added to the area b4 is set as k8. In addition, the visually confirmed liquid level corresponding to the areas b3 and k7 is set as s8, and the visually confirmed liquid level corresponding to the areas b4 and k8 is set as s9.

[0156] In the ink tank 48, the injection port 211 is arranged at the center of the ink container 121 along the Y axis, and the detection unit 60 and the visual confirmation unit 61 are arranged at the ends in the -Y direction. Therefore, the difference between the liquid level s8 and the liquid level s9 becomes large. That is, when ink is added to the area k7 of the ink container 121, there is a possibility that the ink overflows.

[0157] like Fig.23A as well as Fig. 23B As shown, in the ink tank 68, it is difficult to add ink to the area b3, and the area where ink can be added to the area b4 is set as k9. In addition, the visually confirmed liquid level corresponding to the area b3 is set as s10, and the visually confirmed liquid level corresponding to the areas b4 and k9 is set as s11.

[0158] In the ink tank 68, the injection port 111 is arranged at the end of the ink container 121 in the +Y direction, and the detection unit 60 and the visual confirmation unit 61 are arranged at the end of the -Y direction. Therefore, the difference between the liquid level s10 and the liquid level s11 becomes larger than the difference between the liquid level s6 and the liquid level s7. That is, compared with the ink tanks 38 and 58, when the ink container 121 is filled with ink, the ink may overflow.

[0159] As described above, by arranging the injection port 111, the detection unit 60, and the visual confirmation unit 61 at the end of the ink container 121 in the -Y direction along the Y axis, it is possible to suppress the occurrence of ink overflow when filling the ink.

[0160] Explanation of symbols

[0161] 1…printer; 18, 28, 38, 48, 58, 68, 78…ink tank; 60…detection unit; 61…visual confirmation unit; 111, 211…injection port; 113…filter unit; 115…supply unit; 121…ink storage unit; 129…side; L, Lb1, Lb2, Lb3, Lb4…liquid surface.

Claims

1. An ink tank, comprising: An ink storage unit for storing ink; a detection unit configured to detect a position of a liquid level of the ink in the ink containing unit; A supply unit for supplying the ink to the outside; a filter unit disposed in the ink container and interposed between the ink container and the supply unit, In the perspective observation from the side, The filter unit is arranged in a first direction that is vertical to the detection unit. The detection portion is arranged at the center of the ink containing portion in a second direction in a horizontal plane orthogonal to the first direction, and is arranged on a side surface of the ink containing portion intersecting the horizontal plane and having a longer length along the second direction.

2. The ink tank according to claim 1, wherein: The ink receiving portion is provided with an injection port, replenishing the ink into the ink container through the injection port, The injection port is arranged in a direction opposite to the first direction with respect to the ink containing portion.

3. The ink tank according to claim 2, wherein: The injection port is arranged in a direction opposite to the first direction with respect to the detection portion.

4. The ink tank according to claim 2, wherein: A visual confirmation portion is provided, wherein the visual confirmation portion can visually confirm the liquid surface, The visual confirmation portion and the injection port are arranged at one end portion relative to the central portion in the second direction.

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