System

Abstract

To reduce a possibility of false detection of a liquid residual quantity in a system which detects a liquid surface in a tank.SOLUTION: A multifunction machine 10 includes: an ink cartridge 30 having an ink storage chamber 32 and a communication port 35 of the storage chamber 32 to atmospheric air; a connection pipe 107 having an internal space 107A in which ink flowing from the storage chamber 32 through an opening 109 circulates; a tank 103 having an ink storage chamber 121, an inflow port 126 which is located below the opening 109 and through which an ink in the internal space 107A flows into the storage chamber 121, and a communication port 124 of the storage chamber 121 to atmospheric air; a recording part 24 which consumes the ink in the storage chamber 121; and a liquid surface sensor 55. The liquid surface sensor 55 detects a liquid surface in the storage chamber 121 being located in a predetermined position P1 between the opening 109 and the inflow port 126. A horizontal cross sectional area of the storge chamber 121 between the predetermined position P1 and the opening 109 is larger than a horizontal cross sectional area of the internal space 107A.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a system in which a liquid flows between a cartridge and a tank. [Background technology]

[0002] For example, Patent Document 1 discloses a system in which liquid is supplied from a cartridge to a tank by hydraulic head pressure, and then supplied from the tank to a head (consumption unit) that consumes the liquid. In the system disclosed in Patent Document 1, the remaining amount of liquid in the cartridge is detected by a sensor that detects a sensor arm provided in the cartridge. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-238792 Summary of the Invention [Problem to be solved by the invention]

[0004] On the other hand, in systems that supply liquid from a cartridge to a tank using hydraulic head pressure, there are also known systems that detect the amount of liquid remaining in the tank. For example, a system that detects the amount of liquid remaining in the tank using a sensor may detect the amount of liquid remaining in the cartridge in response to that detection. However, such systems may have the following problems.

[0005] In the above system, when liquid is supplied from the tank to the head, the liquid level in the tank may temporarily become lower than the liquid level in the cartridge. As a result, for example, even if there is sufficient liquid remaining in the cartridge, the sensor may detect the liquid level in the tank and determine that there is no liquid remaining in the cartridge that can be supplied to the tank. In other words, the remaining amount of liquid in the cartridge may be incorrectly detected.

[0006] The present invention has been made in consideration of the above circumstances, and its purpose is to provide a system for detecting the amount of liquid remaining in a tank that can reduce the possibility of false detection of the amount of liquid remaining. [Means for solving the problem]

[0007] (1) A system according to the present invention includes a cartridge having a first storage chamber for storing liquid and a first atmosphere communication part that connects the first storage chamber to the atmosphere; a tube to which the cartridge can be connected, the tube having an opening through which liquid flows from the first storage chamber of the connected cartridge and a flow path through which the liquid flowing in through the opening flows; a tank having a second storage chamber for storing liquid, an inlet through which liquid flowing from the first storage chamber of the cartridge connected to the flow path flows into the second storage chamber, and a second atmosphere communication part that connects the second storage chamber to the atmosphere; a consumption part that consumes liquid that flows out of the second storage chamber of the tank; and a detection part that detects when the vertical position of the liquid level of the liquid stored in the second storage chamber reaches a predetermined position. The upper end of the second storage chamber is above the flow path. The lower end of the second storage chamber is below the flow path. The opening is above the inlet. The predetermined position is below the opening and above the inlet. Above the predetermined position and below the opening, the horizontal cross-sectional area of the second storage chamber is larger than the horizontal cross-sectional area of the flow channel.

[0008] In the above configuration, the predetermined position where the detection unit detects the liquid level is below the opening of the pipe and above the inlet of the tank. In other words, the predetermined position is at the same height as the flow path. Therefore, when the liquid level reaches the predetermined position due to the outflow of liquid from the second storage chamber and is detected by the detection unit, the liquid level exists in both the second storage chamber and the flow path.

[0009] Here, in the above configuration, the horizontal cross-sectional area of the second storage chamber is larger than the horizontal cross-sectional area of the flow path above the predetermined position and below the opening. Therefore, when the liquid level is present in the second storage chamber and the flow path, the liquid level in the second storage chamber is unlikely to drop. Therefore, when the liquid level reaches the predetermined position and is detected by the detection unit, there is a high possibility that there is no liquid remaining in the first storage chamber that can be supplied to the second storage chamber. In other words, it is possible to reduce the possibility of erroneous detection, such as detecting that there is no liquid remaining in the first storage chamber that can be supplied to the second storage chamber, when there is sufficient liquid remaining in the first storage chamber.

[0010] (2) The pipe has a vertical portion extending vertically, and the predetermined position is below an upper end of the vertical portion and above a lower end of the vertical portion.

[0011] With this configuration, the liquid level in the flow channel can be easily changed around a predetermined position in the vertical direction, thereby shortening the time it takes for the liquid level in the flow channel and the liquid level in the second storage chamber to become equal due to the head difference.

[0012] (3) The second storage chamber has a first portion and a second portion above the first portion and having a smaller horizontal cross-sectional area than the first portion. The inlet is in communication with the first portion. The detection unit detects the liquid level of the liquid stored in the second portion.

[0013] According to the above configuration, even after the liquid that can be supplied from the first storage chamber of the cartridge to the second storage chamber of the tank has run out, a large amount of liquid remains in the first portion of the second storage chamber, and the liquid remaining in the first portion can be supplied to the consumption unit.

[0014] Furthermore, with the above configuration, the predetermined position is located in the second portion, not the first portion, and the horizontal cross-sectional area of the second portion is smaller than that of the first portion. In other words, the detection unit detects the liquid level in the second portion, which has a smaller horizontal cross-sectional area. Therefore, the detection accuracy by the detection unit can be improved compared to when the predetermined position is located in the first portion.

[0015] (4) The second storage chamber has a third portion located above the second portion and having a larger horizontal cross-sectional area than the second portion.

[0016] According to the above configuration, since the second storage chamber has the third portion, a large amount of liquid can be stored in the second storage chamber.

[0017] (5) For example, the detection unit includes a prism provided at the predetermined position in the second storage chamber, and a light emitting unit that irradiates light toward the prism.

[0018] (6) For example, the detection unit includes a light-emitting unit that irradiates light, and a detectable member that is provided in the second storage chamber and has a float with a specific gravity lower than that of the liquid stored in the second storage chamber, and that moves from one position on the optical path of the light irradiated by the light-emitting unit to another position off the optical path when the vertical position of the liquid level of the liquid stored in the second storage chamber reaches the predetermined position.

[0019] (7) The tank has an outlet through which the liquid stored in the second storage chamber flows out. The outlet is located below the inlet.

[0020] According to the above configuration, even after liquid no longer flows from the first storage chamber of the cartridge to the second storage chamber of the tank through the inlet, liquid located below the inlet and above the outlet in the second storage chamber can be supplied to the consumption section.

[0021] (8) The pipe extends vertically, and the cartridge is connected to the pipe along the vertical direction.

[0022] According to the above configuration, the position of the liquid level in the flow channel is easily changed, thereby shortening the time it takes for the liquid level in the flow channel and the liquid level in the second storage chamber to become equal due to the head difference. [Effects of the Invention]

[0023] According to the present invention, it is possible to reduce the possibility of erroneous detection of the remaining amount of liquid. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a vertical cross-sectional view showing a schematic internal structure of the printer unit 11. As shown in FIG. [Figure 2] FIG. 2 is a vertical cross-sectional view showing a state in which the ink cartridge 30 and the tank 103 are connected. [Figure 3] FIG. 3 is a vertical cross-sectional view showing a state in which the ink cartridge 30 and the tank 103 equipped with the liquid level sensor 55 having the detection target member 55C are connected. [Figure 4] FIG. 4 is a vertical cross-sectional view showing a state in which ink cartridge 30 is connected to tank 103 having connecting pipe 107 with vertical portion 107B. [Figure 5] FIG. 5 is a vertical cross-sectional view that shows a state in which the ink cartridge 30 and the tank 103 with the predetermined position P1 in the third portion 163 are connected. [Figure 6] FIG. 6 is a vertical cross-sectional view showing a state in which the ink cartridge 30 and the tank 103, whose inlet 126 is in communication with the second portion 162, are connected. [Figure 7] FIG. 7(A) is a vertical cross-sectional view schematically showing a tank 103 having only a first portion 161 and a second portion 162, and FIG. 7(B) is a vertical cross-sectional view schematically showing a tank 103 having a rectangular parallelepiped shape. DETAILED DESCRIPTION OF THE INVENTION

[0025] An embodiment of the present invention will be described below. Note that the embodiment described below is merely one example of the present invention, and it goes without saying that the embodiment of the present invention can be modified as appropriate without departing from the spirit of the present invention. Furthermore, the up-down direction 7 is defined based on the position in which the multifunction device 10 is installed on a horizontal surface so that it can be used (the position shown in FIG. 1, which may be referred to as the "usage position"). The front-rear direction 8 is defined as the direction in which sheets 12 are fed from the feed tray 15 of the multifunction device 10, and the left-right direction is defined when the multifunction device 10 is viewed from the front. In FIGS. 1 to 7, the direction toward the back of the paper is the right direction. In this embodiment, in the usage position, the up-down direction 7 corresponds to the vertical direction, and the front-rear direction 8 and the left-right direction correspond to the horizontal direction. The front-rear direction 8 and the left-right direction 9 are orthogonal to each other.

[0026] [First embodiment] [Overall configuration of the multifunction device 10] The multifunction device 10 (an example of a system) has a printer unit 11 that records an image on a sheet 12 using an inkjet recording method. The multifunction device 10 may also have various functions such as a facsimile function, a scanning function, and a copying function. As shown in FIG. 1, the printer unit 11 has a feed tray 15, a discharge tray 16, a feed roller 23, a pair of transport rollers 25, a pair of discharge rollers 27, a recording unit 24, and a platen 26.

[0027] [Feed tray 15, output tray 16, feed roller 23] 1, the feed tray 15 supports a plurality of stacked sheets 12. The discharge tray 16 is disposed above the feed tray 15. The discharge tray 16 supports the sheets 12 discharged by a pair of discharge rollers 27 from between the recording unit 24 and the platen 26. The feed rollers 23 are driven by a motor (not shown) to feed the sheets 12 supported on the feed tray 15 to the conveyance path 17.

[0028] [Transport path 17] The transport path 17 refers to a space formed by the guide members 18 and 19, the recording unit 24, the platen 26, etc. The guide members 18 and 19 face the recording unit 24 and the platen 26 at a predetermined distance inside the printer unit 11. The transport path 17 extends upward from the rear end of the feed tray 15, makes a U-turn, passes through a position facing the recording unit 24, and reaches the discharge tray 16. The transport direction is indicated by the dashed arrow in FIG. 1.

[0029] [25 pairs of conveying rollers] The conveying roller pair 25 is disposed in the conveying path 17. The conveying roller pair 25 includes a conveying roller 25A and a pinch roller 25B that face each other. The conveying roller 25A is driven by a motor (not shown). The pinch roller 25B rotates in conjunction with the rotation of the conveying roller 25A. The sheet 12 is sandwiched between the conveying roller 25A and the pinch roller 25B, which rotate in the forward direction as a forward driving force of the motor is transmitted, and is conveyed in the conveying direction.

[0030] [Discharge Roller Pair 27] The discharge roller pair 27 is disposed downstream of the conveying roller pair 25 in the conveying path 17 in the conveying direction. The discharge roller pair 27 includes a discharge roller 27A and a spur 27B that face each other. The discharge roller 27A is driven by a motor (not shown). The spur 27B rotates in conjunction with the rotation of the discharge roller 27A. The sheet 12 is sandwiched between the discharge roller 27A and the spur 27B, which rotate in the forward direction as the forward driving force of the motor is transmitted, and is conveyed in the conveying direction.

[0031] [Recording unit 24, platen 26] 1, the recording unit 24 (an example of a consumption unit) and the platen 26 are disposed between the pair of transport rollers 25 and the pair of discharge rollers 27 in the transport direction. More specifically, the recording unit 24 and the platen 26 are disposed downstream of the pair of transport rollers 25 in the transport direction and upstream of the pair of discharge rollers 27 in the transport direction. The recording unit 24 and the platen 26 are disposed opposite each other in the up-down direction 7.

[0032] The recording unit 24 includes a carriage 22 and a recording head 21 mounted on the carriage 22. The carriage 22 reciprocates in the left-right direction 9 by receiving driving force from a motor (not shown). A plurality of nozzles 29 are formed on a bottom surface 28 of the recording head 21. The recording head 21 ejects ink droplets from the nozzles 29 by vibrating a vibration element such as a piezoelectric element. As the carriage 22 moves, the recording head 21 selectively ejects ink droplets onto a sheet 12 supported by a platen 26, thereby recording an image on the sheet 12.

[0033] An ink tube 20 and a flexible flat cable (not shown) are connected to the carriage 22. The ink tube 20 connects the tank 103 and the recording head 21. More specifically, the ink tube 20 supplies ink (an example of liquid) stored in each ink cartridge 30 (an example of a cartridge) attached to the tank 103 to the recording head 21. The ink tube 20 is a bundle of four tubes through which ink of each color (black, magenta, cyan, and yellow) flows. The flexible flat cable electrically connects the control board that controls the operation of the multifunction device 10 and the recording head 21.

[0034] [Tank 103] The tank 103 shown in FIG. 2 stores the ink supplied from the ink cartridge 30.

[0035] 2, the tank 103 is box-shaped and has a storage chamber 121 (an example of a second storage chamber) for storing ink therein. The tank 103 is composed of a rear wall 151, a front wall 152, an upper wall 153, a lower wall 154, step walls 156 and 157, and a pair of side walls 155 facing each other in the left-right direction 9.

[0036] The front wall 152 is composed of a first front wall 152A, a second front wall 152B, and a third front wall 152C. The first front wall 152A extends downward from the front end of the upper wall 153. The second front wall 152B is located below and forward of the first front wall 152A and extends upward from the lower wall 154. The third front wall 152C is located between the first front wall 152A and the second front wall 152B in the up-down direction 7 and rearward of the first front wall 152A and the second front wall 152B. The step wall 156 connects the lower end of the first front wall 152A to the upper end of the third front wall 152C. The step wall 157 connects the upper end of the second front wall 152B to the lower end of the third front wall 152C.

[0037] Of the walls constituting the tank 103, at least the portion constituting the prism 55A of the liquid level sensor 55 described later, which is formed on the rear wall 151, is translucent and allows light output from the light-emitting portion 55B of the liquid level sensor 55 to pass through.

[0038] The storage chamber 121 is a space partitioned by a rear wall 151, a front wall 152, an upper wall 153, a lower wall 154, and a pair of side walls 155, and is composed of a first portion 161, a second portion 162, and a third portion 163.

[0039] The first portion 161 is a portion of the storage chamber 121 below the dashed line 131 shown in Figure 2. The first portion 161 is defined by the rear wall 151, the second front wall 152B, the step wall 157, the bottom wall 154, and a pair of side walls 155.

[0040] The second portion 162 is the portion of the storage chamber 121 between the dashed lines 130 and 131 shown in Figure 2. The second portion 162 is defined by the rear wall 151, the third front wall 152C, and a pair of side walls 155. The second portion 162 is located above the first portion 161.

[0041] The third portion 163 is a portion of the storage chamber 121 above the dashed line 130 shown in Figure 2. The third portion 163 is defined by the rear wall 151, the first front wall 152A, the step wall 156, the upper wall 153, and a pair of side walls 155. The third portion 163 is located above the second portion 162.

[0042] The distance in the front-rear direction 8 between the third front wall 152C and the rear wall 151 is shorter than the distance in the front-rear direction 8 between the second front wall 152B and the rear wall 151. Therefore, the horizontal cross-sectional area of the second portion 162 (the area of an imaginary plane surrounded by the third front wall 152C, the rear wall 151, and the pair of side walls 155 when viewed in the up-down direction 7) is smaller than the horizontal cross-sectional area of the first portion 161 (the area of an imaginary plane surrounded by the second front wall 152B, the rear wall 151, and the pair of side walls 155 when viewed in the up-down direction 7).

[0043] The distance in the front-rear direction 8 between the first front wall 152A and the rear wall 151 is longer than the distance in the front-rear direction 8 between the third front wall 152C and the rear wall 151. Therefore, the horizontal cross-sectional area of the third portion 163 (the area of an imaginary plane surrounded by the first front wall 152A, the rear wall 151, and the pair of side walls 155 when viewed in the up-down direction 7) is larger than the horizontal cross-sectional area of the second portion 162.

[0044] The distance in the front-rear direction 8 between the second front wall 152B and the rear wall 151 is longer than the distance in the front-rear direction 8 between the first front wall 152A and the rear wall 151. Therefore, the horizontal cross-sectional area of the first portion 161 is larger than the horizontal cross-sectional area of the third portion 163.

[0045] The first portion 161 of the storage chamber 121 is in communication with the ink tube 20 through the outlet 128. The outlet 128 is formed near the bottom wall 154 that defines the lower end of the storage chamber 121. The outlet 128 is located below the connecting pipe 107. The ink stored in the storage chamber 121 flows out from the outlet 128 and is supplied to the recording head 21 through the ink tube 20.

[0046] A communication port 124 (an example of a second atmosphere communication portion) is formed in the upper wall 153. The communication port 124 penetrates the upper wall 153. The third portion 163 of the storage chamber 121 and the outside (atmosphere) of the tank 103 are communicated through the communication port 124. The communication port 124 may be closed by a semipermeable membrane.

[0047] [Connecting pipe 107] 2, a connecting pipe 107 (an example of a pipe) extends upward from the step wall 157. In other words, the connecting pipe 107 extends in the up-down direction 7. The connecting pipe 107 is disposed at a position corresponding to the ink supply unit 34 of the ink cartridge 30 installed in the multifunction device 10.

[0048] The connecting pipe 107 is made of a resin and has a circular pipe shape. An opening 109 is formed at the protruding tip of the connecting pipe 107. An inlet 126 is also formed in the stepped wall 157. The inlet 126 is located below the opening 109 and above the outlet 128. The inlet 126 connects the internal space 107A (an example of a flow path) of the connecting pipe 107 with a first portion 161 of the storage chamber 121.

[0049] In a predetermined range R1 below opening 109 and above a predetermined position P1 described below, the horizontal cross-sectional area of first portion 161 of storage chamber 121 is larger than the horizontal cross-sectional area of internal space 107A (the area of an imaginary surface surrounded by the inner surface of connecting pipe 107 when viewed in the vertical direction 7). Furthermore, internal space 107A is located below an upper end P2 of storage chamber 121 and above a lower end P3 of storage chamber 121 in the vertical direction 7.

[0050] [Liquid level sensor 55] The liquid level sensor 55 (an example of a detection unit) uses a prism 55A, which has a reflectivity that varies depending on whether or not the ink is in contact with the liquid level sensor 55, to detect that the liquid level of the ink in the storage chamber 121 has reached a predetermined position P1.

[0051] The predetermined position P1 is a position below the opening 109 of the connecting pipe 107 and above the inlet 126 in the vertical direction 7. In this embodiment, the predetermined position P1 is the position of the second portion 162 of the storage chamber 121 of the tank 103 in the vertical direction 7. That is, the liquid level sensor 55 detects the liquid level of the ink stored in the second portion 162.

[0052] The liquid level sensor 55 includes a prism 55A, a light-emitting unit 55B, and a light-receiving unit (not shown). The prism 55A is formed by a portion of the rear wall 151 that defines the first portion 161 of the storage chamber 121, extending to and adjacent to a predetermined position P1. The light-emitting unit 55B and the light-receiving unit are disposed behind the prism 55A and facing the prism 55A. The light-emitting unit 55B emits light toward the prism 55A. The light-receiving unit receives light emitted from the light-emitting unit 55B and reflected by the prism 55A, and outputs a signal based on the intensity of the received light to the control board.

[0053] When the ink level stored in the storage chamber 121 is higher than a predetermined position P1, the ink comes into contact with the prism 55A on the optical path of the light irradiated from the light-emitting unit 55B. At this time, the light irradiated from the light-emitting unit 55B to the prism 55A passes through the prism 55A and enters the storage chamber 121, and does not reach the light-receiving unit. At this time, the light-receiving unit outputs a low-level signal to the control board. On the other hand, when the ink level stored in the storage chamber 121 is below the predetermined position P1, the ink does not come into contact with the prism 55A on the optical path of the light irradiated from the light-emitting unit 55B. At this time, the light irradiated from the light-emitting unit 55B to the prism 55A is reflected by the prism 55A and reaches the light-receiving unit. At this time, the light-receiving unit outputs a high-level signal to the control board.

[0054] In response to receiving a high level signal after receiving a low level signal from the liquid level sensor 55, the controller mounted on the control board notifies the user that the ink stored in the storage chamber 32 of the ink cartridge 30 (described in detail below) can no longer be supplied to the tank 103. The notification may be made, for example, via a display on the multifunction device 10. In other words, the controller determines whether the ink stored in the storage chamber 32 of the ink cartridge 30 can be supplied to the tank 103 based on the remaining amount of ink stored in the storage chamber 121 of the tank 103.

[0055] [Ink Cartridge 30] The ink cartridge 30 is a container in which ink is stored. As shown in FIG. 2, the ink cartridge 30 has a housing 31 and an ink supply unit 34. The housing 31 is substantially rectangular parallelepiped in shape. The ink cartridges 30, which store different colors of ink, may have the same or different external shapes. The housing 31 is made up of a rear wall 40, a front wall 41, an upper wall 39, a lower wall 42, and a pair of side walls 37 that face each other in the left-right direction. The internal space of the housing 31 is a storage chamber 32 (an example of a first storage chamber) that stores ink.

[0056] The ink supply unit 34 protrudes downward from near the front end of the bottom wall 42. The ink supply unit 34 is a cylindrical member. The internal space of the ink supply unit 34 communicates with the storage chamber 32 through an outlet 33 that penetrates the bottom wall 42. The protruding end of the ink supply unit 34 opens to the outside of the ink cartridge 30. Although not shown in the figures, the opening at the protruding end of the ink supply unit 34 may be closed by a seal member, a valve, or the like, and may be configured to be opened during use.

[0057] A communication port 35 (an example of a first atmosphere communication portion) is formed in the upper wall 39. The communication port 35 penetrates the upper wall 39 of the housing 31. The storage chamber 32 and the outside (atmosphere) of the ink cartridge 30 are communicated through the communication port 35. The communication port 35 may be closed by a semipermeable membrane.

[0058] 2, the ink cartridge 30 is connected to the tank 103 from above. More specifically, the ink supply unit 34 of the ink cartridge 30 is connected to the connecting tube 107 of the tank 103 by inserting the connecting tube 107 of the tank 103 into the internal space of the ink supply unit 34 of the ink cartridge 30 from below. In other words, the ink cartridge 30 is connected to the connecting tube 107 along the up-down direction 7.

[0059] When the ink cartridge 30 and the tank 103 are connected, the ink stored in the storage chamber 32 of the ink cartridge 30 flows from the storage chamber 32 through the opening 109 of the connecting tube 107 of the tank 103 into the internal space 107A of the connecting tube 107. The ink flows downward through the internal space 107A and flows into the first portion 161 of the storage chamber 121 of the tank 103 through the inlet 126. In this way, when the ink cartridge 30 and the tank 103 are connected, ink can flow between the storage chamber 32 of the ink cartridge 30 and the storage chamber 121 of the tank 103 through the internal space 107A of the connecting tube 107.

[0060] 2 is the usage orientation of the multifunction device 10. In the usage orientation, the multifunction device 10 performs various operations such as image recording. Below, the process in which ink stored in the ink storage chamber 32 of the ink cartridge 30 and the ink storage chamber 121 of the tank is consumed by the execution of image recording, and detection is performed by the liquid level sensor 55, will be described.

[0061] When the ink cartridge 30 is attached to the cartridge attachment section 110, ink can flow between the storage chamber 32 and the storage chamber 121, and the liquid level in the storage chamber 32 and the liquid level in the storage chamber 121 become equal due to the head difference.

[0062] When image recording is performed, ink stored in the ink storage chambers 32 and 121 flows out of the outlet 128 to the recording head 21. The amount of ink flowing out of the ink storage chamber 32 is not necessarily equal to the amount of ink flowing out of the ink storage chamber 121. Therefore, the liquid level in one of the ink storage chambers 32 and 121 may temporarily be lower than the liquid level in the other ink storage chamber 32 or 121. However, over time, the liquid level in the ink storage chamber 32 and the liquid level in the ink storage chamber 121 become equal due to the difference in head pressure. As a result, the liquid levels in the ink storage chambers 32 and 121 decrease as ink is consumed during image recording. The decreased liquid level is then positioned between the internal space 107A of the connecting pipe 107 and the second portion 162 of the ink storage chamber 121. This liquid level is indicated by a dashed line in FIG. 2 as position P6.

[0063] When image recording is performed with the ink level at position P6, the ink stored in the ink storage chambers 32 and 121 is consumed. As a result of this consumption, the ink level in the second portion 162 of the ink storage chamber 121 drops to a predetermined position P1, and the ink level sensor 55 outputs a high-level signal to the controller. Upon receiving this high-level signal, the controller notifies the controller that the ink stored in the ink storage chamber 32 of the ink cartridge 30 can no longer be supplied to the tank 103.

[0064] Here, at position P6, which is above predetermined position P1 and below opening 109, the horizontal cross-sectional area of second portion 162 is larger than the horizontal cross-sectional area of internal space 107A. Therefore, the liquid level in second portion 162 is less likely to fall below the liquid level in internal space 107A. In other words, the liquid level in internal space 107A is more likely to fall than the liquid level in second portion 162. In other words, when the liquid level in second portion 162 reaches predetermined position P1 during the image recording described above, the liquid level in internal space 107A is likely to be located below predetermined position P1. In other words, when the above-described notification is issued, it is likely that the ink stored in storage chamber 32 of ink cartridge 30 cannot be supplied to tank 103.

[0065] [Effects of this embodiment] According to this embodiment, the predetermined position P1 at which the liquid level sensor 55 detects the liquid level is below the opening 109 of the connecting pipe 107 and above the inlet 126 of the tank 103. In other words, the predetermined position P1 is at the same height as the internal space 107A of the connecting pipe 107. Therefore, when the liquid level reaches the predetermined position P1 due to the outflow of ink from the storage chamber 121 and is detected by the liquid level sensor 55, the liquid level exists in both the storage chamber 121 and the internal space 107A.

[0066] Here, in this embodiment, the horizontal cross-sectional area of storage chamber 121 above predetermined position P1 and below opening 109 is larger than the horizontal cross-sectional area of internal space 107A of connecting pipe 107. Therefore, when the liquid level is present in storage chamber 121 and internal space 107A, the liquid level in storage chamber 121 is unlikely to drop. Therefore, when the liquid level reaches predetermined position P1 and is detected by liquid level sensor 55, it is highly likely that there is no ink remaining in storage chamber 32 that can be supplied to storage chamber 121. In other words, it is possible to reduce the possibility of erroneous detection, such as detecting that there is no ink remaining in storage chamber 32 that can be supplied to storage chamber 121, when there is a sufficient amount of ink remaining in storage chamber 32.

[0067] Furthermore, according to this embodiment, the position of the liquid level in internal space 107A is easily changed because internal space 107A extends in the vertical direction 7 around predetermined position P1 in the vertical direction 7. This reduces the time it takes for the liquid level in internal space 107A and the liquid level in storage chamber 121 to become equal due to the head difference.

[0068] Furthermore, according to this embodiment, even after all the ink that can be supplied from the storage chamber 32 of the ink cartridge 30 to the storage chamber 121 of the tank 103 has run out, a large amount of ink remains in the first portion 161 of the storage chamber 121. The ink remaining in the first portion 161 can then be supplied to the recording unit 24.

[0069] Furthermore, according to this embodiment, the predetermined position P1 is located in the second portion 162 rather than the first portion 161, and the horizontal cross-sectional area of the second portion 162 is smaller than the horizontal cross-sectional area of the first portion 161. In other words, the liquid level sensor 55 detects the liquid level in the second portion 162, which has a smaller horizontal cross-sectional area. Therefore, the detection accuracy of the liquid level sensor 55 can be improved compared to when the predetermined position P1 is located in the first portion 161.

[0070] Furthermore, according to this embodiment, since the storage chamber 121 has the third portion 163, a large amount of ink can be stored in the storage chamber 121.

[0071] Furthermore, according to this embodiment, the outlet 128 is located below the inlet 126. Therefore, even after ink no longer flows from the storage chamber 32 of the ink cartridge 30 to the storage chamber 121 of the tank 103 through the inlet 126, ink that is below the inlet 126 and above the outlet 128 in the storage chamber 121 can be supplied to the recording unit 24.

[0072] Furthermore, according to this embodiment, since connecting pipe 107 extends in the vertical direction 7, the position of the liquid level in internal space 107A of connecting pipe 107 is easily changed. This makes it possible to shorten the time until the liquid level in internal space 107A and the liquid level in storage chamber 121 become equal due to the head difference.

[0073] [Variations] In the above embodiment, the liquid level sensor 55 uses the prism 55A. However, the liquid level sensor 55 may have any other known configuration.

[0074] For example, the liquid level sensor 55 may be configured as shown in Fig. 3. The liquid level sensor 55 shown in Fig. 3 includes a detectable member 55C arranged in the storage chamber 121, a light emitting unit 55B, and a light receiving unit (not shown).

[0075] The detected member 55C has a float 61 and an arm 62. The float 61 has a specific gravity smaller than that of the ink stored in the storage chamber 121. Therefore, the float 61 generates buoyancy when present in the ink within the storage chamber 121. The arm 62 extends upward from the float 61. A tip 62A of the arm 62 is plate-shaped. The detected member 55C is supported by the tank 103 so as to be rotatable about a rotation shaft 63 formed at the bottom.

[0076] The light-emitting unit 55B and the light-receiving unit are disposed opposite each other on either side of the tank 103 in the left-right direction. The light-emitting unit 55B emits light toward the light-receiving unit. The light-receiving unit receives the light emitted from the light-emitting unit 55B and outputs a signal based on the intensity of the received light to the control board. Note that in order to shorten the left-right distance between the light-emitting unit 55B and the light-receiving unit and ensure that the light from the light-emitting unit 55B reaches the light-receiving unit, the left-right length of the tank 103 in the portion between the light-emitting unit 55B and the light-receiving unit may be configured to be shorter than the left-right length of the tank 103 in other portions.

[0077] When the liquid level of the ink stored in the storage chamber 121 is higher than the predetermined position P1, the buoyancy of the float 61 causes the detectable member 55C to be in the first position shown by the solid line in FIG. 3. At this time, the tip 62A of the arm 62 of the detectable member 55C is located between the light-emitting element 55B and the light-receiving element in the left-right direction, i.e., on the optical path of the light emitted by the light-emitting element 55B. Therefore, the light emitted from the light-emitting element 55B is blocked by the tip 62A of the arm 62 and does not reach the light-receiving element. At this time, the light-receiving element outputs a low-level signal to the control board.

[0078] When the ink level stored in the storage chamber 121 drops below the predetermined position P1, the float 61 descends along with the ink level. This causes the detected member 55C to rotate to the second position indicated by the dashed line in FIG. 3. At this time, the tip 62A of the arm 62 is retracted from between the light-emitting element 55B and the light-receiving element in the left-right direction, i.e., is out of the optical path of the light emitted by the light-emitting element 55B. Therefore, the light emitted from the light-emitting element 55B reaches the light-receiving element. At this time, the light-receiving element outputs a high-level signal to the control board.

[0079] Alternatively, for example, an electrode rod inserted into the storage chamber 121 may be used as the liquid level sensor 55. In this case, two electrode rods are arranged in the storage chamber 121. The two electrode rods are mounted on a substrate (not shown). The lower end of one of the two electrodes is located slightly higher than the predetermined position P1. The lower end of the other of the two electrodes is located lower than the predetermined position P1. Whether or not a current flows through the ink between the two electrodes is then used to detect whether or not the liquid level of the ink stored in the storage chamber 121 is below the predetermined position P1.

[0080] The configuration of tank 103 is not limited to that shown in Figure 2, and may have various configurations as described below, as long as it satisfies the conditions that the upper end of storage chamber 121 is above internal space 107A of connecting pipe 107, the lower end of storage chamber 121 is below internal space 107A of connecting pipe 107, and the horizontal cross-sectional area of storage chamber 121 above predetermined position P1 and below opening 109 is greater than the horizontal cross-sectional area of internal space 107A.

[0081] In the above embodiment, the connecting pipe 107 of the tank 103 extends in the vertical direction 7, but it may extend in a direction other than the vertical direction 7. For example, the connecting pipe 107 may extend in a direction inclined with respect to the vertical direction 7. Also, in the above embodiment, the ink cartridge 30 is connected to the connecting pipe 107 along the vertical direction 7, but it may be connected to the connecting pipe 107 along a direction other than the vertical direction 7 (for example, the front-rear direction 8).

[0082] For example, as shown in Figure 4, if the ink cartridge 30 and the tank 103 are configured so that the ink cartridge 30 is connected to the tank 103 from the front, the connecting pipe 107 of the tank 103 may have a vertical portion 107B extending in the up-down direction 7 and a horizontal portion 107C extending in the front-rear direction 8. If the connecting pipe 107 is configured to have the vertical portion 107B, the predetermined position P1 is located below the upper end P4 of the vertical portion 107B and above the lower end P5 of the vertical portion 107B. In the configuration shown in Figure 4, only a portion of the connecting pipe 107 is the vertical portion 107B, whereas in the above embodiment (the configuration shown in Figure 2), the entire connecting pipe 107 is a vertical portion.

[0083] In the above embodiment, the predetermined position P1 was located in the second portion 162. That is, the liquid level sensor 55 detected the liquid level in the second portion 162. Therefore, the prism 55A of the liquid level sensor 55 in the above embodiment and the detected member 55C of the liquid level sensor 55 in the above modified example were formed in the second portion 162. However, the predetermined position P1 may be located somewhere other than the second portion 162. That is, the liquid level sensor 55 may be configured to detect the liquid level in a place other than the second portion 162.

[0084] For example, as shown in Figure 5, when the tank 103 is configured so that the lower end of the third portion 163 is below the opening 109, the predetermined position P1 may be located in the third portion 163. In other words, the liquid level sensor 55 may detect the liquid level in the third portion 163.

[0085] In the above embodiment, the inlet 126 communicates with the first portion 161 of the storage chamber 121, but it may also communicate with a portion other than the first portion 161. For example, as shown in FIG. 6, the inlet 126 may also communicate with the second portion 162.

[0086] In the above embodiment, the horizontal cross-sectional area of first portion 161 is larger than that of second portion 162, the horizontal cross-sectional area of third portion 163 is larger than that of second portion 162, and the horizontal cross-sectional area of first portion 161 is larger than that of third portion 163. However, the relationship in size between the horizontal cross-sectional areas of first portion 161, second portion 162, and third portion 163 is not limited to the above, and for example, the horizontal cross-sectional area of second portion 162 may be larger than that of first portion 161 or third portion 163.

[0087] The tank 103 does not have to have a shape including all of the first portion 161, the second portion 162, and the third portion 163 as shown in Fig. 2. For example, the tank 103 may have a shape including only the first portion 161 and the second portion 162, but not the third portion 163, as shown in Fig. 7(A). In the configuration shown in Fig. 7(A), the second portion 162 is defined by the rear wall 151, the third front wall 152C, the top wall 153, and a pair of side walls 155. Furthermore, for example, the tank 103 may have a simple rectangular parallelepiped shape as shown in Fig. 7(B).

[0088] In the above embodiment, the communication opening 124 is formed in the upper wall 153. However, the communication opening 124 may be formed in a location other than the upper wall 153, for example, in the first front wall 152A.

[0089] In the above embodiment, the communication opening 35 is formed in the upper wall 39. However, the communication opening 35 may be formed in a location other than the upper wall 39, for example, in the front wall 41.

[0090] In the above embodiment, ink is described as an example of a liquid, and the recording unit 24 is described as an example of a consumption unit, but this is not limiting. For example, if the present invention is applied to an apparatus that applies a pretreatment liquid to paper or the like using a roller prior to ink application during printing, the pretreatment liquid is an example of a liquid, and the roller is an example of a consumption unit. [Explanation of symbols]

[0091] 10. Multifunction printer (system) 24 Recording unit (consumer unit) 30···Ink cartridge (cartridge) 32...Storage chamber (1st storage chamber) 35... Communication port (first atmosphere communication part) 55 Liquid level sensor (detection part) 103 Tank 107 Connecting pipe (pipe) 107A...Internal space 109...Aperture 121...Storage chamber (second storage chamber) 124... communication port (second atmosphere communication part)

Claims

1. a cartridge having a first storage chamber for storing a liquid and a first atmosphere communication part for communicating the first storage chamber with the atmosphere; a tube to which the cartridge can be connected, the tube having an opening through which liquid flows from the first storage chamber of the connected cartridge, and a flow path through which the liquid flowing in through the opening flows; a tank having a second storage chamber for storing a liquid, an inlet through which the liquid flowing from the first storage chamber of the cartridge connected to the tube via the flow path flows into the second storage chamber, and a second atmosphere communication part that communicates the second storage chamber with the atmosphere; a consumption unit that consumes the liquid that flows out of the second storage chamber of the tank; a detection unit that detects that the vertical position of the liquid level of the liquid stored in the second storage chamber has reached a predetermined position, the first storage chamber of the cartridge connected to the tube is always in communication with the atmosphere through the first atmosphere communication part, The upper end of the second storage chamber is located above the flow path, The lower end of the second storage chamber is located below the flow path, the opening is located above the inlet; the predetermined position is below the opening and above the inlet, A system in which the horizontal cross-sectional area of the second storage chamber is larger than the horizontal cross-sectional area of the flow path above the predetermined position and below the opening.

2. 2. The system of claim 1, wherein the second reservoir has a single liquid level at the predetermined position.

3. The pipe has a vertical portion extending in a vertical direction, 3. The system according to claim 1, wherein the predetermined position is below the upper end of the vertical section and above the lower end of the vertical section.

4. The second storage chamber comprises: A first part; and a second portion located above the first portion and having a horizontal cross-sectional area smaller than that of the first portion, the inlet is in communication with the first portion; The system according to claim 1 , wherein the detection unit detects the level of the liquid stored in the second portion.

5. 5. The system of claim 4, wherein the upper end of the second portion is above the upper end of the tube.

6. 6. The system according to claim 4 or 5, wherein the second storage chamber has a third portion located above the second portion and having a larger horizontal cross-sectional area than the second portion.

7. The detection unit is a prism provided at the predetermined position in the second storage chamber; The system according to claim 1 , further comprising: a light emitting unit that irradiates light toward the prism.

8. The detection unit is a light-emitting unit that irradiates light; A system as described in any one of claims 1 to 6, comprising a detectable member provided in the second storage chamber, having a float with a specific gravity lower than that of the liquid stored in the second storage chamber, and which moves from one position on the optical path of the light irradiated by the light-emitting unit to another position off the optical path when the vertical position of the liquid level stored in the second storage chamber reaches the predetermined position.

9. the tank has an outlet through which the liquid stored in the second storage chamber flows out, 9. The system of claim 1, wherein the outlet is located below the inlet.

10. The tube extends vertically, The system according to any one of claims 1 to 9, wherein the cartridge is connected to the pipe along the vertical direction.

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