Tank and image recorder

Abstract

To provide a tank designed such that the detection accuracy of a sensor for detecting an amount of remaining liquid is less likely to decrease even when the bottom surface of the tank is inclined with respect to a horizontal plane.SOLUTION: A tank 18 includes a liquid storage chamber 111, a first sensor 125, and a second sensor 126. The first sensor 125 outputs a first signal when liquid is detected at a first detection position P1 of the liquid storage chamber 111, and outputs a second signal when liquid is not detected at the first detection position P1. The second sensor 126 outputs a third signal when liquid is detected at the second detection position P2 of the liquid storage chamber 111, and outputs a fourth signal when liquid is not detected at the second detection position P2. The first detection position P1 and the second detection position P2 are horizontally separated from each other. The first detection position P1 and the second detection position P2 are lower than an inflow port 143 in an upside-downside direction 7. An outflow port 111B is lower than the first detection position P1 and the second detection position P2 in the upside-downside direction 7.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a tank to which a liquid container for storing liquid can be connected, and to an image recording device. [Background technology]

[0002] Patent Document 1 discloses a tank to which a liquid cartridge can be connected. The tank described in Patent Document 1 has a sensor on the rear wall that detects when the ink level in the tank reaches a first position. The first position is located near an outlet located on the bottom wall of the tank. When the ink level drops to the first position, a notification is issued based on the detection by the sensor. This allows the user to know that the amount of ink remaining in the tank or cartridge is low. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-163684 A Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, for example, when the printer is placed on a surface that is inclined with respect to the horizontal plane, the bottom surface of the tank becomes inclined with respect to the horizontal plane. In this case, the liquid level in the tank becomes inclined with respect to the bottom surface of the tank, so even if there is enough ink stored in the tank that the ink level in the tank is higher than the first position when the bottom surface of the tank is horizontal, the sensor may not detect the ink. In this way, when the bottom surface of the tank is inclined with respect to the horizontal plane, the accuracy of the sensor in detecting the remaining ink level is likely to decrease.

[0005] The present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide a tank and an image recording device in which the accuracy of the sensor's detection of the remaining amount of liquid is not likely to decrease even if the bottom surface of the tank is inclined with respect to the horizontal plane. [Means for solving the problem]

[0006] (1) The tank according to the present invention is a tank to which a liquid container for storing liquid can be connected. The tank includes a liquid storage chamber for storing liquid supplied from the liquid container, a first sensor, and a second sensor. The liquid storage chamber has an inlet for allowing the liquid supplied from the liquid container to flow in, and an outlet for allowing the liquid stored in the liquid storage chamber to flow out. The first sensor outputs a first signal when liquid is detected at a first detection position of the liquid storage chamber, and outputs a second signal when liquid is not detected at the first detection position. The second sensor outputs a third signal when liquid is detected at a second detection position of the liquid storage chamber, and outputs a fourth signal when liquid is not detected at the second detection position. The first detection position and the second detection position are separated in the horizontal direction. The first detection position and the second detection position are lower than the inlet in the up-down direction. The outlet is lower than the first detection position and the second detection position in the up-down direction.

[0007] Assume that the liquid storage chamber is stored with an amount of liquid such that the liquid level of the liquid stored in the liquid storage chamber is higher than the first detection position when the image recording device equipped with the tank is placed on a horizontal surface. When the image recording device is placed on a surface inclined with respect to the horizontal plane, the bottom surface of the tank is inclined with respect to the horizontal plane. At this time, the liquid level of the liquid stored in the liquid storage chamber is inclined with respect to the bottom surface of the liquid storage chamber, but since the first sensor and the second sensor positioned at a horizontal distance from the first sensor are provided, even if the liquid level of the liquid becomes lower than one of the first detection position and the second detection position, it is likely to become higher than the other of the first detection position and the second detection position. In this state, a first signal indicating that the liquid has been detected at the first detection position or a third signal indicating that the liquid has been detected at the second detection position is output. In other words, even if the liquid storage chamber contains an amount of liquid that would cause the liquid level in the liquid storage chamber to be higher than the first detection position when the image recording device is placed on a horizontal surface, the sensor can be prevented from not detecting the liquid, thereby preventing a decrease in the accuracy of the sensor's detection of the remaining amount of liquid.

[0008] (2) The liquid storage chamber may be a rectangular parallelepiped space that is long in one direction along a horizontal direction. The first sensor may be located on one side of a center of the liquid storage chamber in the one direction. The second sensor may be located on the other side of the liquid storage chamber opposite to the one side of a center of the liquid storage chamber in the one direction.

[0009] Since the tank has a rectangular parallelepiped internal space that is long in one direction along the horizontal direction, when the bottom surface of the tank is tilted in one direction with respect to the horizontal plane, the liquid level of the liquid stored in the liquid storage chamber is significantly displaced in the vertical direction relative to the first sensor located on one side of the liquid storage chamber and the second sensor located on the other side of the liquid storage chamber, which makes it possible to more effectively prevent a decrease in the accuracy of the sensors in detecting the remaining amount of liquid.

[0010] (3) The first sensing position and the second sensing position may be at the same position in the up-down direction.

[0011] This makes it possible to more reliably prevent a decrease in the accuracy with which the sensor detects the amount of remaining ink.

[0012] (4) The image recording device according to the present invention includes the tank, a liquid container connected to the tank, an ejection head that ejects the liquid supplied through the outlet, an alarm, and a controller, the controller executing an alarm in the alarm unit to notify the user that the remaining amount of liquid is low on the condition that the second signal and the fourth signal are received.

[0013] Assume that the liquid is stored in the liquid storage chamber in an amount such that the liquid level of the liquid stored in the liquid storage chamber is higher than the first detection position when the image recording device is placed on a horizontal surface. When the image recording device is placed on a surface inclined relative to the horizontal surface, the liquid level of the liquid stored in the liquid storage chamber is inclined relative to the bottom surface of the liquid storage chamber. At this time, since the first sensor and the second sensor located horizontally spaced apart from the first sensor are provided, even if the liquid level of the liquid becomes lower than one of the first detection position and the second detection position, it is likely to become higher than the other of the first detection position and the second detection position. From this state, when the liquid supplied through the outlet of the tank is discharged from the discharge head, the liquid level of the liquid stored in the liquid storage chamber decreases. Then, when the liquid level of the liquid stored in the liquid storage chamber becomes lower than the other of the first detection position and the second detection position, the controller executes a notification indicating that the remaining amount of the liquid is low in the notification unit. Therefore, even if the level of the liquid stored in the liquid storage chamber is inclined with respect to the bottom surface of the liquid storage chamber, the sensor is prevented from issuing an alert when the amount of liquid stored in the liquid storage chamber is such that the level of the liquid stored in the liquid storage chamber is higher than the first detection position when the image recording device is placed on a horizontal surface (when there is a sufficient amount of liquid remaining), and as a result, it is possible to prevent a decrease in the accuracy of the sensor in detecting the amount of remaining liquid.

[0014] (5) The outlet may be located on the second detection position side of the center between the first detection position and the second detection position in the horizontal direction. The controller may cause the notification unit to issue a notification indicating that the remaining amount of liquid is low, on condition that the second signal has not been received after a first predetermined time has elapsed since receiving the fourth signal.

[0015] Since the outlet is located closer to the second detection position than the center between the first detection position and the second detection position, the outlet is likely to be exposed from the liquid due to a drop in the liquid level between when the controller receives the fourth signal and when it receives the second signal. When the outlet is exposed from the liquid, air may flow into the ejection head through the outlet. In the above configuration, the controller issues a notification indicating that the remaining amount of liquid is low in the notification unit, on condition that the controller has not received the second signal after the first predetermined time has elapsed since receiving the fourth signal. This prevents the sensor from detecting the remaining amount of liquid from decreasing in accuracy, and allows the user to prevent the outlet from being exposed from the liquid level by, for example, connecting a liquid container to the tank and refilling the tank with liquid from the liquid container, or replacing the liquid container connected to the tank with a new liquid container.

[0016] (6) The outlet may be located on the first detection position side of a center between the first detection position and the second detection position in the horizontal direction. The controller may cause the notification unit to issue a notification indicating that the remaining amount of liquid is low, on condition that the fourth signal has not been received after a first predetermined time has elapsed since receiving the second signal.

[0017] Since the outlet is located closer to the first detection position than the center between the first detection position and the second detection position, the outlet is likely to be exposed from the liquid due to a drop in the liquid level between when the controller receives the second signal and when it receives the fourth signal. When the outlet is exposed from the liquid, air may flow into the ejection head through the outlet. In the above configuration, the controller executes a notification indicating that the remaining amount of liquid is low in the notification unit, on condition that the fourth signal has not been received after the first predetermined time has elapsed since the second signal was received. This prevents the accuracy of the sensor in detecting the remaining amount of liquid from decreasing, and the user can prevent the outlet from being exposed from the liquid level by, for example, connecting a liquid container to the tank and refilling the tank with liquid from the liquid container, or replacing the liquid container connected to the tank with a new liquid container.

[0018] (7) The controller may cause the alarm unit to issue an alarm indicating that the tank's attitude is tilted, on condition that after receiving one of the second signal and the fourth signal, the other of the second signal and the fourth signal is not received until a second predetermined time longer than the first predetermined time has elapsed.

[0019] If the controller does not receive the other of the second signal and the fourth signal within a second predetermined time longer than the first predetermined time after receiving one of the second signal and the fourth signal, the bottom surface of the liquid storage chamber is greatly inclined with respect to the horizontal plane. If the bottom surface of the liquid storage chamber is greatly inclined with respect to the horizontal plane, the outlet is likely to be exposed from the liquid surface when the liquid level of the liquid stored in the liquid storage chamber drops. In the above configuration, the user can know that the attitude of the tank is greatly inclined by the notification from the notification unit, and can correct the attitude of the tank, for example, by repositioning the image recording device. Effect of the Invention

[0020] According to the present invention, even if the bottom surface of the tank is inclined with respect to the horizontal plane, the accuracy with which the sensor detects the remaining amount of liquid is unlikely to decrease. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is an external perspective view of a multifunction peripheral 10 according to this embodiment, in which (A) shows a state in which a scanner unit 12 is in a closed position, and (B) shows a state in which the scanner unit 12 is in an open position. [Diagram 2] FIG. 2 is a vertical cross-sectional view showing a schematic internal structure of the printer unit 11. As shown in FIG. [Diagram 3] FIG. 3 is a schematic diagram showing the recording unit 21, the black tank 18, and the peripheral configuration of the black tank 18. As shown in FIG. [Figure 4] FIG. 4 is a block diagram of the controller 130. [Diagram 5] FIG. 5 is a flow chart showing the process of the controller 130 for detecting the remaining ink level. [Figure 6] FIG. 6 is a diagram showing a state in which the black tank 18, in which the outlet 111B is located at the front end of the bottom wall 154, is tilted in the front-rear direction 8 so that the rear is lower than the horizontal plane. [Figure 7] FIG. 7 is a diagram showing a state in which the black tank 18, in which the outlet 111B is located at the rear end of the lower wall 154, is tilted in the front-rear direction 8 so that the front is lower than the horizontal plane. [Figure 8] FIG. 8 is another flowchart showing the process of the controller 130 for detecting the remaining ink level. [Figure 9] FIG. 9 is a diagram showing a state in which the black tank 18, in which the outlet 111B is located at the center of the lower wall 154 in the front-rear direction 8, is tilted in the front-rear direction 8 so that the rear is lower than the horizontal plane. [Figure 10] FIG. 10 is another flowchart showing the process of the controller 130 for detecting the remaining ink level.

[0022] A first embodiment of the present invention will be described below. The first embodiment described below is merely one example of the present invention, and it goes without saying that the first embodiment of the present invention can be modified as appropriate without changing the gist of the present invention. In the following description, the direction is expressed as the progress from the starting point of the arrow to the end point, and the movement on the line connecting the starting point and the end point of the arrow. In other words, the direction is one component of the direction. Furthermore, the up-down direction 7 is defined based on the posture (see FIG. 1, sometimes referred to as the "use posture") in which the multifunction device 10 and the black tank 18 and the three-color tank 19 installed in the multifunction device 10 are installed on a horizontal surface so that they can be used, the front-rear direction 8 is defined with the surface of the housing 14 of the multifunction device 10 where the opening 13 (see FIG. 1) is provided as the front, and the left-right direction 9 is defined when the multifunction device 10 is viewed from the front. The up-down direction 7, the front-rear direction 8, and the left-right direction 9 are perpendicular to each other.

[0023] [First embodiment] [Overall configuration of multifunction device 10] As shown in Fig. 1(A), the multifunction device 10 has a generally rectangular parallelepiped shape. The multifunction device 10 has a scanner unit 12 and a printer unit 11. The multifunction device 10 may also have a facsimile function. The multifunction device 10 is an example of an image recording device.

[0024] [Scanner unit 12, housing 15] As shown in FIG. 1A, the scanner unit 12 is located at the top of the multifunction device 10. The scanner unit 12 is disposed in a housing 15. The housing 15 is generally rectangular parallelepiped in shape. The housing 15 is connected to the housing 14 by a connector 16 near the rear wall of the housing 14. The connector 16 allows the housing 15 to rotate relative to the housing 14. As shown in FIG. 1B, when the front part of the housing 15 is lifted by the user of the multifunction device 10, the housing 15 is opened relative to the housing 14. In the space between the scanner unit 12 and the printer unit 11, i.e., above the printer unit 11, the recording unit 21 (see FIG. 2) and covers 100A, 100B, etc., located inside the housing 14, are exposed to the outside. In this state, the user can operate the covers 100A, 100B, etc. As shown in FIG. 1A, when the housing 15 is closed, the recording unit 21, covers 100A and 100B, etc. are not exposed to the outside.

[0025] [Printer unit 11, housing 14] The printer unit 11 is located at the bottom of the multifunction device 10, and records an image on a sheet-like recording medium 5 (see FIG. 2) by an inkjet recording method. The recording medium 5 is, for example, paper, cloth, a plastic sheet, an OHP sheet, an envelope, etc.

[0026] The printer unit 11 includes a feed path 71 (see FIG. 1B) and a feed tray 17 (see FIG. 1A) in the housing 15. The feed path 71 is a path through which the recording medium 5 (see FIG. 2) on which an image is recorded passes. The feed tray 17 opens and closes the feed path 71 on the upper surface of the housing 15. The feed tray 17 closes the feed path 71 in a first state (a state shown by a solid line in FIG. 1) in which the feed tray 17 is rotated so as to form a part of the upper surface of the housing 15. On the other hand, the feed tray 17 opens the feed path 71 in a second state (a state shown by a broken line in FIG. 1) in which the feed tray 17 is rotated so as to protrude rearward from the housing 14. In the second state, the upper surface of the feed tray 17 becomes a tray surface that supports the recording medium 5 and guides it to the feed path 71.

[0027] The printer unit 11 has a housing 14. The housing 14 has a roughly rectangular parallelepiped shape and a box shape that is open at the top. An opening 13 is formed in a front wall 14A of the housing 14. The printer unit 11 has a conveying unit 20, a conveying path 72, a recording unit 21, and a discharge tray 22 in the internal space of the housing 14, as shown in FIG.

[0028] The transport unit 20 transports the recording medium 5 on the feed tray 17 via the feed path 71 to a transport path 72, i.e., below the head 21A of the recording unit 21. In this embodiment, the transport unit 20 has an upstream transport unit 20a and a downstream transport unit 20b. The upstream transport unit 20a is located near the feed path 71 on the downstream side of the transport direction of the feed path 71. The downstream transport unit 20b is located near the recording unit 21 on the upstream side of the transport direction of the recording unit 21. The transport unit 20 is connected to a controller 130 (see FIG. 4). Driving of the transport unit 20 is controlled by the controller 130.

[0029] The conveying path 72 is a path along which the recording medium 5 that has passed through the feeding path 71 is conveyed. The conveying path 72 extends from the position of the upstream conveying section 20a to the downstream conveying section 20b, and is formed below the recording unit 21, extending from the downstream conveying section 20b to the front of the recording unit 21.

[0030] The recording unit 21 includes a head 21A and a guide rail 21B that guides the head 21A in the left-right direction 9. Ink stored in the black tank 18 and the three-color tanks 19 is supplied to the head 21A. The head 21A ejects ink toward the recording medium 5 from a plurality of nozzles formed on a lower surface 21C of the head 21A. This causes an image to be recorded on the recording medium 5. In other words, the recording unit 21 consumes ink. The recording unit 21 is connected to a controller 130 (see FIG. 4). The ejection of ink from the head 21A is controlled by the controller 130. The head 21A is an example of an ejection head.

[0031] 1, the discharge tray 22 is disposed in the opening 13 of the housing 14, below and in front of the recording unit 21. The discharge tray 22 supports a sheet on which an image has been recorded by the recording unit 21.

[0032] [Black Tank 18, 3-color Tank 19] 1, the multifunction device 10 further includes a black tank 18 and a three-color tank 19 inside the housing 14. The black tank 18 and the three-color tank 19 are fixed inside the housing 14. The black tank 18 and the three-color tank 19 being fixed in the housing 14 means that the black tank 18 and the three-color tank 19 are not expected to be replaced by the user, and ink is replenished in a state where the black tank 18 and the three-color tank 19 are fixed to the housing 14.

[0033] The black tank 18 is placed in the tank housing section 101A in a usage position. The black tank 18 stores black ink. Black ink is an example of a liquid. The tank housing section 101A is disposed to the left of the opening 13 at the front end of the housing 14. The space within the tank housing section 101A is partitioned by the bottom (not shown) of the housing 14, the front wall 14A, the left wall 14B, the top wall 14C, etc. The top wall 14C is disposed at the top ends of the front wall 14A and the left wall 14B, etc., and closes the top end of the space within the tank housing section 101A. An opening 14D is formed in the center of the top wall 14C. An inlet 143 of the black tank 18 is exposed from the opening 14D.

[0034] 3, the black tank 18 has a generally rectangular parallelepiped shape and includes a housing 141, a first remaining amount sensor 125, and a second remaining amount sensor 126. The black tank 18 is an example of a tank.

[0035] [Chassis 141] The housing 141 is made of a resin material such as polypropylene. The resin material has a degree of translucency that allows the amount of ink stored in the black tank 18 to be visually confirmed from the outside through a window formed in the front wall 14A (see FIG. 1). The housing 141 is integrally molded by injection molding the resin material. Note that the housing 141 does not have to be integrally molded, and may instead be configured by combining a plurality of members.

[0036] Housing 141 includes front wall 151, right wall 152, upper wall 153, lower wall 154, and rear wall 155. The left end of housing 141 is closed by a left wall (not shown). Note that the left side of housing 141 may be open due to reasons related to the molding of housing 141. In this case, a film (not shown) is welded to the left end face of housing 141, thereby sealing the left side of housing 141.

[0037] [Ink Reservoir 111] An ink storage chamber 111 is defined by a front wall 151, a right wall 152, an upper wall 153, a lower wall 154, a rear wall 155, and a left wall. The ink storage chamber 111 is a rectangular parallelepiped space that is longer in a front-to-rear direction 8 than in a left-to-right direction 9. The ink storage chamber 111 is capable of storing ink. An inlet 143, an air vent 111A, and an outlet 111B open into the ink storage chamber 111.

[0038] The inlet 143 is disposed at a position forward of the center on the upper surface of the upper wall 153. The inlet 143 protrudes upward from the upper surface of the upper wall 153. An opening is formed at the upper end of the inlet 143. The inlet 143 communicates between the ink storage chamber 111 and the outside of the black tank 18. A user can inject ink into the ink storage chamber 111 from the outside through the inlet 143. The inlet 143 is an example of an inlet. A cap 104 that seals the inlet 143 is removably fitted into the inlet 143.

[0039] The atmosphere communication port 111A is located behind the injection port 143 in the upper wall 153. A semipermeable membrane may be attached to the upper wall 153 so as to close the atmosphere communication port 111A. The semipermeable membrane is a porous membrane that blocks the passage of ink and has minute holes that allow the passage of air.

[0040] The outlet 111B is located at the front end of the lower wall 154. One end of the ink tube 32A is connected to the outlet 111B. The other end of the ink tube 32A is connected to the head 21A. The ink tube 32A is made of an elastically deformable resin material. The ink in the ink storage chamber 111 flows out from the outlet 111B into the ink tube 32A, and is supplied to the head 21A through the ink tube 32A. The ink storage chamber 111 is an example of a liquid storage chamber.

[0041] [First remaining amount sensor 125] The first remaining amount sensor 125 detects when the ink level in the ink storage chamber 111 reaches a first detection position P1. The first remaining amount sensor 125 includes a prism 125A, a light emitting portion 125B, and a light receiving portion 125C (see FIG. 4).

[0042] Prism 125A is located at a position lower than the center of front wall 151 in the up-down direction 7. Prism 125A constitutes a part of front wall 151. Prism 125A is made of glass having a reflectance that varies depending on whether ink is in contact with it or not. As a result, first detection position P1 is set at the position of prism 125A.

[0043] The light-emitting unit 125B and the light-receiving unit 125C face the prism 125A in front of the prism 125A. The light-emitting unit 125B and the light-receiving unit 125C are supported on the front surface of the front wall 151. The light-emitting unit 125B and the light-receiving unit 125C may be supported on the rear surface of the front wall 14A in the tank accommodating unit 101A. The light-emitting unit 125B emits light toward the prism 125A. The light-emitting unit 125B is electrically connected to the controller 130 (see FIG. 4). The light emission of the light-emitting unit 125B is controlled by the controller 130.

[0044] The light receiving unit 125C receives light that is irradiated from the light emitting unit 125B and reflected by the prism 125A. The light receiving unit 125C is electrically connected to the controller 130. The light receiving unit 125C outputs a signal to the controller 130 based on the intensity of the received reflected light.

[0045] Specifically, when the level of the ink stored in the ink storage chamber 111 is higher than the first detection position P1, the ink comes into contact with the prism 125A on the optical path of the light irradiated from the light emitting unit 125B. At this time, the light emitted from the light emitting unit 125B toward the prism 125A passes through the prism 125A and enters the ink storage chamber 111, and does not reach the light receiving unit 125C. At this time, the light receiving unit 125C outputs a low level signal (an example of a first signal) to the controller 130. On the other hand, when the level of the ink stored in the ink storage chamber 111 is equal to or lower than the first detection position P1, the ink does not come into contact with the prism 125A on the optical path of the light emitted from the light emitting unit 125B. At this time, the light irradiated from the light emitting unit 125B to the prism 125A is reflected by the prism 125A and reaches the light receiving unit 125C. At this time, the light receiving unit 125C outputs a high level signal (an example of a second signal) to the controller 130. The light receiving unit 125C may output a high level signal when the level of the ink stored in the ink storage chamber 111 is equal to or higher than the first detection position P1, and may output a low level signal when the level of the ink stored in the ink storage chamber 111 is lower than the first detection position P1. The first remaining amount sensor 125 is an example of a first sensor.

[0046] [Second remaining amount sensor 126] The second remaining amount sensor 126 detects when the ink level in the ink storage chamber 111 reaches a second detection position P2. The second remaining amount sensor 126 includes a prism 126A, a light emitting portion 126B, and a light receiving portion 126C (see FIG. 4).

[0047] The prism 126A is set at a position lower than the center of the rear wall 155 in the vertical direction 7. In this embodiment, the prism 126A is located at the same height as the prism 125A in the vertical direction 7. The prism 126A constitutes a part of the rear wall 155. The prism 126A is made of glass having a reflectance that differs depending on whether or not the ink is in contact with the glass. As a result, the second detection position P2 is set at the position of the prism 126A. The distance in the front-rear direction 8 between the second detection position P2 and the first detection position P1 is preferably longer than half the length of the storage chamber 111 along the front-rear direction 8. In this embodiment, the distance in the front-rear direction 8 between the second detection position P2 and the first detection position P1 is approximately equal to the distance in the front-rear direction 8 between the rear surface of the front wall 151 and the front surface of the rear wall 155.

[0048] The light-emitting unit 126B and the light-receiving unit 126C face the prism 126A behind the prism 126A. The light-emitting unit 126B and the light-receiving unit 126C are supported on the rear surface of the rear wall 155. The light-emitting unit 125B and the light-receiving unit 126C may be supported on a wall surface that defines the tank housing unit 101A. The light-emitting unit 125B emits light toward the prism 125A. The light-emitting unit 126B is electrically connected to the controller 130 (see FIG. 4). The light emission of the light-emitting unit 126B is controlled by the controller 130.

[0049] The light receiving unit 126C receives light that is irradiated from the light emitting unit 126B and reflected by the prism 126A. The light receiving unit 126C is electrically connected to the controller 130. The light receiving unit 126C outputs a signal to the controller 130 based on the intensity of the received reflected light.

[0050] Specifically, when the level of the ink stored in the ink storage chamber 111 is higher than the second detection position P2, the ink comes into contact with the prism 126A on the optical path of the light irradiated from the light emitting unit 126B. At this time, the light emitted from the light emitting unit 126B toward the prism 126A passes through the prism 126A and enters the ink storage chamber 111, and does not reach the light receiving unit 126C. At this time, the light receiving unit 126C outputs a low level signal (an example of a third signal) to the controller 130. On the other hand, when the level of the ink stored in the ink storage chamber 111 is equal to or lower than the second detection position P2, the ink does not come into contact with the prism 126A on the optical path of the light emitted from the light emitting unit 126B. At this time, the light irradiated from the light emitting unit 126B to the prism 126A is reflected by the prism 126A and reaches the light receiving unit 126C. At this time, the light receiving unit 126C outputs a high level signal (an example of a fourth signal) to the controller 130. The light receiving unit 126C may output a high level signal when the liquid level of the ink stored in the ink storage chamber 111 is equal to or higher than the second detection position P2, and may output a low level signal when the liquid level of the ink stored in the ink storage chamber 111 is lower than the second detection position P2. The second remaining amount sensor 126 is an example of a second sensor.

[0051] In FIG. 1, the three-color tank 19 is placed in the tank housing section 101B (see FIG. 1). The three-color tank 19 stores three colors of ink (one example of liquid), namely cyan, magenta, and yellow. The three-color tank 19 has the same configuration as the black tank 18 for each of the three colors (see FIG. 2). Therefore, a detailed description of the configuration of the three-color tank 19 will be omitted. Compared to the tank housing section 101A, the tank housing section 101B has a similar configuration to the tank housing section 101A, except that the tank housing section 101B is disposed to the right of the opening 13 at the front end of the internal space of the housing 14, the size of the internal space is different, and three openings for the injection ports 143 are formed in the upper wall 14C. Therefore, a detailed description of the configuration of the tank housing section 101B will be omitted.

[0052] [Display 25] The multifunction device 10 further includes a display 25 (see FIG. 1 and FIG. 4). The display 25 is located on the front wall of the housing 15. The display 25 displays a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low. The display 25 displays a message indicating that the attitude of the black tank 18 is tilted. Examples of messages include "Tank attitude is tilted", "Printer attitude is tilted", "Please place the printer on a horizontal surface", and "The printer attitude is tilted, so please place the printer on a horizontal surface". The display 25 is connected to the controller 130 (see FIG. 4). The display of the display 25 is controlled by the controller 130. The display 25 may display the same information for the three-color tank 19 as that for the black tank 18. The display 25 is an example of an alarm unit.

[0053] [Controller 130] The printer unit 11 further includes a controller 130 inside the housing 14. As shown in FIG. 4, the controller 130 includes a CPU 131, a ROM 132, a RAM 133, an EEPROM 134, and an ASIC 135, which are connected by an internal bus 137. The ROM 132 stores programs and the like for the CPU 131 to control various operations. The RAM 133 is used as a storage area for temporarily recording data, signals, and the like used when the CPU 131 executes the programs, or as a working area for data processing. The EEPROM 134 stores settings, flags, and the like that should be retained even after the power is turned off.

[0054] The EEPROM 134 stores, for example, an initial flag. The initial flag is a value that corresponds to whether or not the multifunction device 10 has executed an initial process. Specifically, the initial flag indicates a first value that corresponds to the fact that the initial process has not yet been executed, or a second value that corresponds to the fact that the initial process has already been executed. The initial process is a process of filling the flow path from the ink storage chamber 111 to the recording unit 21, i.e., the ink tube 32A, with ink.

[0055] At the time of shipment of the multifunction device 10, the flow path from the ink storage chamber 111 to the recording unit 21 is not filled with ink. That is, at the time of shipment of the multifunction device 10, a first value is set in the initial flag. Then, the controller 130 executes the initial process, so that the ink tube 32A and the head 21A are filled with ink, and the multifunction device 10 is in a state in which it is possible to record an image on the recording medium 5. That is, after the initial process is executed, a second value is set in the initial flag. At the time of shipment of the multifunction device 10, a shipping liquid dedicated to the time of shipment, which is not used for recording an image on paper, may be filled in the flow path instead of ink. In this case, when the controller 130 executes the initial process, the shipping liquid in the flow path is discharged, and the flow path is filled with ink.

[0056] The transport unit 20, the recording unit 21, the display 25, the first remaining amount sensor 125, and the second remaining amount sensor 126 are electrically connected to the ASIC 135. The controller 130 causes the transport unit 20 to transport the recording medium 5. The controller 130 causes the head 21A of the recording unit 21 to eject ink.

[0057] The controller 130 causes the display 25 to display a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low, on the condition that high level signals are received from the first remaining amount sensor 125 and the second remaining amount sensor 126. The controller 130 causes the display 25 to display a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low, on the condition that a high level signal is not received from the second remaining amount sensor 126 after a first predetermined time has elapsed since the controller 130 received a high level signal from the first remaining amount sensor 125. The first predetermined time is, for example, 10 minutes. The controller 130 causes the display 25 to display a message indicating that the attitude of the black tank 18 is tilted, on the condition that a high level signal is not received from the first remaining amount sensor 125 until a second predetermined time has elapsed since the controller 130 received a high level signal from the second remaining amount sensor 126. The second predetermined time is a time longer than the first predetermined time. The second predetermined time is, for example, 20 minutes.

[0058] [Image recording processing] Next, an image recording process using the multifunction device 10 will be described. For example, when the controller 130 receives print data indicating an image to be recorded on the recording medium 5 from an information processing device capable of communicating with the multifunction device 10, the controller 130 drives the conveying unit 20. As a result, the recording medium 5 on the feed tray 17 is fed to below the head 21A via the feed path 71. Next, the controller 130 ejects ink from a plurality of nozzles of the head 21A toward the recording medium 5. As a result, an image is recorded on the recording medium 5. At this time, when the ink in the ink storage chamber 111 is consumed by the ejection of the ink, air flows into the ink storage chamber 111 through the air communication port 111A. Then, as the ink is ejected, the liquid level of the ink in the ink storage chamber 111 decreases. Next, the controller 130 drives the conveying unit 20 to eject the recording medium 5 on which the image has been recorded to the ejection tray 22. Then, the controller 130 repeats the above process until there is no more print data to be recorded on the recording medium 5.

[0059] [Ink remaining amount detection process] Next, the process of detecting the remaining amount of ink executed by the controller 130 during the image recording process will be described with reference to Fig. 5. In the initial state, it is assumed that the ink chamber 111 is stored with an amount of ink such that the liquid level of the ink stored in the ink chamber 111 is higher than the first detection position P1 and the second detection position P2 when the multifunction device 10 is placed on a horizontal surface.

[0060] The controller 130 first determines whether or not a high level signal (an example of a second signal) has been received from the first remaining amount sensor 125 (S1). If the controller 130 determines that a high level signal has been received from the first remaining amount sensor 125 (S1: Yes), the process proceeds to S2. If the controller 130 determines in S1 that a high level signal has not been received from the first remaining amount sensor 125 (S1: No), the process proceeds to S5.

[0061] In S2, the controller 130 determines whether or not a high level signal (an example of a fourth signal) has been received from the second remaining amount sensor 126. If the controller 130 determines that a high level signal has been received from the second remaining amount sensor 126 (S2: Yes), the controller 130 proceeds to processing S3. If the controller 130 has not received a high level signal from the second remaining amount sensor 126 (S2: No), the controller 130 proceeds to processing S10.

[0062] In S3, the controller 130 stops the transport unit 20 and causes the display 25 to display a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low. This allows the user to know that the remaining amount of ink is low, so that the user can replenish ink into the black tank 18 before the remaining amount of ink reaches 0. Ink is replenished, for example, by removing the cap 104 of the black tank 18 and inserting the nozzle of an ink bottle (an example of a liquid container) that stores ink into the inlet 143.

[0063] Next, the controller 130 waits until it receives a resume command input by the user (S4: No). On condition that it receives the resume command, the controller 130 drives the transport unit 20 and returns the process to S1 (S4: Yes).

[0064] In S5, if the controller 130 determines that it has not received a high-level signal from the second remaining amount sensor 126 (S5: No), the process returns to S1. In S5, if the controller 130 determines that it has received a high-level signal from the second remaining amount sensor 126 (S5: Yes), the process proceeds to S6.

[0065] In S6, if the controller 130 determines that a high level signal has been received from the first remaining amount sensor 125 (S6: Yes), the process proceeds to S3. In S6, if the controller 130 determines that a high level signal has not been received from the first remaining amount sensor 125 (S6: No), the process proceeds to S7.

[0066] In S7, if the controller 130 determines that the second predetermined time has not elapsed since receiving a high-level signal from the second remaining amount sensor 126 (S7: No), the controller 130 returns the process to S6.

[0067] In S7, if the controller 130 determines that the second predetermined time has elapsed since receiving a high-level signal from the second remaining amount sensor 126 (S7: Yes), the controller 130 advances the process to S8. In S8, the controller 130 stops the conveying unit 20 and displays a message on the display 25 indicating that the attitude of the black tank 18 is tilted. This allows the user to know that the attitude of the black tank 18 is tilted, and the user can correct the attitude of the black tank 18 by placing the multifunction device 10 on a horizontal surface. Next, the controller 130 waits until it receives a resume command input by the user (S9: No). On the condition that the controller 130 receives the resume command, it drives the conveying unit 20 and returns the process to S1 (S9: Yes).

[0068] In S10, if the controller 130 determines that the first predetermined time has not elapsed since receiving a high-level signal from the first remaining amount sensor 125 (S10: No), the process returns to S2. If the controller 130 determines that the first predetermined time has elapsed since receiving a high-level signal from the first remaining amount sensor 125 (S10: Yes), the process proceeds to S3. Then, the above process is repeated until there is no print data to be recorded on the recording medium 5.

[0069] [Effects of the first embodiment] In the multifunction device 10, the first remaining amount sensor 125 and the second remaining amount sensor 126 are positioned at an interval in the front-rear direction 8. For this reason, for example, as shown in FIG. 6, when the multifunction device 10 is placed on a surface that is inclined in the front-rear direction 8 so that the rear side is lower than the horizontal plane, and the bottom surface of the ink storage chamber 111 is inclined with respect to the horizontal plane, the ink level is likely to be higher than the second detection position P2 even if it is lower than the first detection position P1. In this state, a low level signal indicating that ink has been detected at the second detection position P2 is output from the second remaining amount sensor 126. In other words, it is possible to avoid the ink level not being detected even if the ink storage chamber 111 contains an amount of ink that causes the ink level in the ink storage chamber 111 to be higher than the first detection position P1 and the second detection position P2 when the multifunction device 10 is placed on a horizontal plane. Therefore, even if the multifunction device 10 is placed on a surface that is inclined with respect to the horizontal plane, the accuracy with which the first remaining amount sensor 125 and the second remaining amount sensor 126 detect the remaining amount of ink is unlikely to decrease.

[0070] In the multifunction device 10, the ink storage chamber 111 is a rectangular parallelepiped space that is longer in the front-to-rear direction 8 than in the left-to-right direction 9. Therefore, when the bottom surface of the black tank 18 is tilted in the front-to-rear direction 8 with respect to the horizontal plane, the liquid level of the ink stored in the ink storage chamber 111 is significantly displaced in the up-down direction 7 relative to the first remaining amount sensor 125 located on the front wall 151 and the second remaining amount sensor 126 located on the rear wall 155. This more effectively prevents a decrease in the accuracy of detecting the remaining amount of ink by the first remaining amount sensor 125 and the second remaining amount sensor 126.

[0071] In the multifunction device 10, the first detection position P1 and the second detection position P2 are set at the same height in the up-down direction 7. This more reliably prevents the accuracy of the first remaining ink amount sensor 125 and the second remaining ink amount sensor 126 from decreasing.

[0072] In the multifunction device 10, after receiving a high level signal from one of the first remaining amount sensor 125 and the second remaining amount sensor 126, on the condition that the controller 130 receives a high level signal from the other of the first remaining amount sensor 125 and the second remaining amount sensor 126, the controller 130 causes the display 25 to display a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low. Therefore, even if the liquid level of the ink stored in the ink storage chamber 111 is inclined with respect to the bottom surface of the ink storage chamber 111, in a state in which the ink level of the ink stored in the ink storage chamber 111 is higher than the first detection position P1 and the second detection position P2 when the multifunction device 10 is placed on a horizontal surface, the controller 130 is prevented from causing the display 25 to display a message indicating that the remaining amount of ink stored in the ink storage chamber 111 is low in a state in which the ink level of the ink stored in the ink storage chamber 111 is higher than the first detection position P1 and the second detection position P2 when the multifunction device 10 is placed on a horizontal surface. This prevents the accuracy of the first remaining amount sensor 125 and the second remaining amount sensor 126 in detecting the remaining amount of ink from decreasing.

[0073] In the multifunction device 10, the outlet 111B is located at the front end of the bottom wall 154, and is therefore located closer to the first detection position P1 than the center in the front-rear direction 8 between the first detection position P1 and the second detection position P2. For this reason, for example, as shown in Fig. 6, when the multifunction device 10 is placed on a surface that is inclined in the front-rear direction 8 so that the rear is lower than the horizontal plane, the outlet 111B is likely to become exposed from the ink due to a drop in the ink level in the ink storage chamber 111 between the time when the controller 130 receives a high level signal from the first remaining amount sensor 125 and the time when it receives a high level signal from the second remaining amount sensor 126. When the outlet 111B is exposed from the ink, there is a possibility that air will flow into the head 21A through the outlet 111B. In the multifunction device 10, the controller 130 causes the display 25 to display a message indicating that the remaining amount of ink is low, on the condition that a high level signal has not been received from the second remaining amount sensor 126 after a first predetermined time has elapsed since receiving a high level signal from the first remaining amount sensor 125. This prevents a decrease in the accuracy of detecting the remaining amount of ink by the first remaining amount sensor 125 and the second remaining amount sensor 126, and also prevents the outlet 111B from being exposed to ink when the user connects an ink bottle to the black tank 18 and refills the black tank 18 with ink from the ink bottle.

[0074] In the multifunction device 10, if the controller 130 does not receive a high level signal from the other of the first remaining amount sensor 125 and the second remaining amount sensor 126 within a second predetermined time that is longer than the first predetermined time after receiving a high level signal from one of the first remaining amount sensor 125 and the second remaining amount sensor 126, the bottom surface of the ink storage chamber 111 is inclined significantly with respect to the horizontal plane. If the bottom surface of the ink storage chamber 111 is inclined significantly with respect to the horizontal plane, the outlet 111B is likely to be exposed from the ink level when the level of the ink stored in the ink storage chamber 111 drops. In the multifunction device 10, the controller 130 causes the display 25 to display a message indicating that the attitude of the black tank 18 is inclined, on the condition that the controller 130 does not receive a high level signal from the first remaining amount sensor 125 until the second predetermined time has elapsed after receiving a high level signal from the second remaining amount sensor 126. Therefore, the user can know from the message on the display 25 that the attitude of the black tank 18 is significantly tilted, and can correct the attitude of the black tank 18 by, for example, repositioning the multifunction device 10.

[0075] [Variations] In the multifunction device 10, the first detection position P1 and the second detection position P2 are separated in the front-rear direction 8, but they need only be separated in the horizontal direction. For example, the first detection position P1 and the second detection position P2 may be separated in the left-right direction 9.

[0076] In the multifunction device 10, an ink bottle can be connected to the black tank 18 as a liquid container for storing liquid, but an ink cartridge may be connected to the black tank 18 as a liquid container for storing liquid. In this case, the inlet through which ink flows from the ink cartridge into the ink storage chamber 111 of the black tank 18 is set at a position lower than the first detection position P1 and the second detection position P2.

[0077] In the multifunction device 10, the outlet 111B is located in the lower wall 154, but it is sufficient if it is located in a position lower than the first detection position P1 and the second detection position P2 in the vertical direction 7. For example, the outlet 111B may be located in the lower end of the front wall 151 or the lower end of the rear wall 155.

[0078] In the multifunction device 10, the ink storage chamber 111 is a rectangular parallelepiped space that is longer in the front-rear direction 8 than in the left-right direction 9, but the present invention is not limited to this as long as it is capable of storing ink.

[0079] In the multifunction device 10, the first detection position P1 and the second detection position P2 are located at the same position in the vertical direction 7, but they may be slightly offset from each other in the vertical direction 7.

[0080] In the multifunction device 10, the controller 130 causes the display device 25 to display a message, but the present invention is not limited to this as long as the message can be notified to the user. For example, the controller 130 may cause an alarm device to output a sound instead of the display device 25.

[0081] In the multifunction device 10, the first remaining amount sensor 125 and the second remaining amount sensor 126 are prism-type photosensors using prisms 125A, 126A, light-emitting elements 125B, 126B, and light-receiving elements 125C, 126C, but the present invention is not limited to this as long as the light-receiving element can output different electrical signals depending on the presence or absence of light emitted from the light-emitting element. For example, the first remaining amount sensor 125 and the second remaining amount sensor 126 may be a transmission type photosensor, a separation type photosensor, a reflection type photosensor, or an actuator type photosensor. The first remaining amount sensor 125 and the second remaining amount sensor 126 may also be a water level sensor using three electrodes. In this case, the three electrodes are arranged in the ink storage chamber 111 with a gap therebetween in the front-rear direction 8, for example. The three electrodes are connected to an electrical circuit so that different electrical signals are output when two of the three electrodes come into contact with the ink.

[0082] In the multifunction device 10, the outlet 111B is located at the front end of the bottom wall 154, but may be located at the rear end of the bottom wall 154, for example, as shown in FIG. 7. In this case, the ink remaining amount detection process executed by the controller 130 during the image recording process is the same as the ink remaining amount detection process in the first embodiment, except that the signals received by the controller 130 at S1, S2, S5, and S6 in the first embodiment are reversed to those in the first embodiment, as shown in FIG. 8. For this reason, the same processes as those in the first embodiment in the ink remaining amount detection process shown in FIG. 8 are denoted by the same reference numerals as in the first embodiment, and the description thereof is omitted. The first predetermined time shown in FIG. 8 may be different from the first predetermined time shown in FIG. 5. Also, the second predetermined time shown in FIG. 8 may be different from the second predetermined time shown in FIG. 5.

[0083] In the black tank 18 shown in Fig. 7, the outlet 111B is located at the rear end of the bottom wall 154, and is therefore located closer to the second detection position P2 than the center in the front-rear direction 8 between the first detection position P1 and the second detection position P2. For this reason, for example, as shown in Fig. 7, when the multifunction device 10 is placed on a surface that is inclined in the front-rear direction 8 so that the front is lower than the horizontal plane, the outlet 111B is likely to be exposed from the ink due to a drop in the liquid level of the ink storage chamber 111 between the time when the controller 130 receives a high level signal from the second remaining amount sensor 126 and the time when it receives a high level signal from the first remaining amount sensor 125. When the outlet 111B is exposed from the ink, there is a possibility that air will flow into the head 21A through the outlet 111B.

[0084] 7, the controller 130 causes the display 25 to display a message indicating that the remaining amount of ink is low, on condition that a high level signal has not been received from the first remaining amount sensor 125 after a first predetermined time has elapsed since receiving a high level signal from the second remaining amount sensor 126. This prevents a decrease in the accuracy of detecting the remaining amount of ink by the first remaining amount sensor 125 and the second remaining amount sensor 126, and also prevents the user from being exposed to ink by connecting an ink bottle to the black tank 18 and refilling the black tank 18 with ink from the ink bottle.

[0085] In the multifunction device 10, the outlet 111B is located at the front end of the lower wall 154, but may be located at the center of the lower wall 154 in the left-right direction 9, as shown in FIG. 9. In this case, even if the multifunction device 10 according to the modified example shown in FIG. 9 is placed on a surface inclined in the front-rear direction 8 with respect to the horizontal plane, the outlet 111B is less likely to be exposed from the ink when the ink level drops, compared to when the outlet 111B is located on one side of the center of the lower wall 154 in the front-rear direction 8. For this reason, in the multifunction device 10 according to the modified example shown in FIG. 9, in the process of detecting the remaining ink level, as shown in FIG. 10, the process corresponding to S10 in the first embodiment is omitted, and instead, a process corresponding to S7 in the first embodiment is executed. In the following, the same processes as those in the first embodiment in the process of detecting the remaining ink level shown in FIG. 10 are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted, and only the differences are described.

[0086] As shown in FIG. 10, in S21, if the controller 130 determines that the second predetermined time has not elapsed since receiving a high-level signal from the first remaining amount sensor 125 (S21: No), the process returns to S2. In S21, if the controller 130 determines that the second predetermined time has elapsed since receiving a high-level signal from the first remaining amount sensor 125 (S21: Yes), the process proceeds to S22. In S22, the controller 130 stops the conveying unit 20 and displays a message indicating that the attitude of the black tank 18 is tilted on the display 25. This allows the user to know that the attitude of the black tank 18 is tilted, so that the user can correct the attitude of the black tank 18 by placing the multifunction device 10 on a horizontal surface. Next, the controller 130 waits until it receives a resume command input by the user (S23: No). On the condition that the controller 130 receives the resume command, the controller 130 drives the conveying unit 20 and returns the process to S1 (S23: Yes). [Explanation of symbols]

[0087] 10. Multifunction printer (image recording device) 18···Black Tank (Tank) 19. 3-color tank (tank) 21A···Head (ejection head) 25 Display (alarm section) 111 Ink storage chamber (liquid storage chamber) 111B... Outlet 130...Controller 143...Inlet (inlet) 125... 1st remaining amount sensor (1st sensor) 126 Second remaining amount sensor (Second sensor) P1: First detection position P2: Second detection position

Claims

1. A tank to which a liquid container for storing liquid can be connected, a liquid storage chamber for storing the liquid supplied from the liquid container; A first sensor; a second sensor, the liquid storage chamber has an inlet through which liquid supplied from the liquid container flows in, and an outlet through which liquid stored in the liquid storage chamber flows out, the first sensor outputs a first signal when liquid is detected at a first detection position of the liquid storage chamber, and outputs a second signal when liquid is not detected at the first detection position; the second sensor outputs a third signal when liquid is detected at a second detection position of the liquid storage chamber, and outputs a fourth signal when liquid is not detected at the second detection position; The first sensing position and the second sensing position are separated in a horizontal direction, The first detection position and the second detection position are lower than the inlet in a vertical direction, The outlet of the tank is lower than the first detection position and the second detection position in the up-down direction.

2. The liquid storage chamber is a rectangular parallelepiped space that is elongated in one direction along the horizontal direction, the first sensor is located on one side of the center of the liquid storage chamber in the one direction, The tank according to claim 1 , wherein the second sensor is located on the other side of the liquid storage chamber opposite the one side from the center in the one direction.

3. The tank according to claim 1 , wherein the first detection position and the second detection position are at the same position in the vertical direction.

4. A tank according to any one of claims 1 to 3; a liquid container connected to the tank; a discharge head that discharges the liquid supplied through the outlet; A notification department; A controller, The image recording device, wherein the controller, on condition that the second signal and the fourth signal are received, executes a notification in the notification section, indicating that the remaining amount of liquid is low.

5. the outlet is located closer to the second detection position than a center between the first detection position and the second detection position in the horizontal direction, The image recording device of claim 4, wherein the controller causes the notification unit to issue a notification indicating that a remaining amount of liquid is low, on condition that the second signal has not been received after a first predetermined time has elapsed since receiving the fourth signal.

6. the outlet is located closer to the first detection position than a center between the first detection position and the second detection position in the horizontal direction, The image recording device of claim 4, wherein the controller causes the notification unit to issue a notification indicating that a remaining amount of liquid is low, on condition that the fourth signal has not been received after a first predetermined time has elapsed since receiving the second signal.

7. The image recording device described in claim 5 or 6, wherein the controller executes an alarm in the alarm unit to indicate that the tank's attitude is tilted, on the condition that after receiving one of the second signal and the fourth signal, the other of the second signal and the fourth signal is not received until a second predetermined time longer than the first predetermined time has elapsed.

Images