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 Art

[0002] For example, Patent Document 1 discloses a system in which a liquid is supplied from a cartridge to a tank by a water head pressure and the liquid is 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 the liquid in the cartridge is detected by detecting a sensor arm provided in the cartridge with a sensor.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, in a system in which a liquid is supplied from a cartridge to a tank by a water head pressure, a system for detecting the remaining amount of the liquid in the tank is also known. In a configuration for detecting the remaining amount of the liquid in the tank, for example, when the remaining amount of the liquid in the tank is detected by a sensor, a system for detecting the remaining amount of the liquid in the cartridge in response to the detection can be considered. However, in such a system, the following problems may occur.

[0005] In the above system, when the 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. Therefore, for example, even though there is sufficient liquid remaining in the cartridge, the sensor may detect that there is no liquid remaining in the cartridge that can be supplied to the tank by detecting the liquid level in the tank. That is, the remaining liquid amount in the cartridge is erroneously detected.

[0006] The present invention has been made in view of the above circumstances, and an object thereof is to provide a system capable of reducing the possibility of erroneously detecting the remaining liquid amount in a system for detecting the remaining liquid amount in a tank.

Means for Solving the Problems

[0007] (1) The system according to the present invention includes a cartridge having a first storage chamber for storing a liquid and a first air communication portion for communicating the first storage chamber with the atmosphere, a tube to which the cartridge can be connected and having an opening through which the liquid flows in from the first storage chamber of the connected cartridge and a flow path through which the liquid flowing in through the opening circulates, a second storage chamber for storing a liquid, an inlet through which the liquid flowing through the flow path from the first storage chamber of the cartridge connected to the tube flows into the second storage chamber, and a tank having a second air communication portion for communicating the second storage chamber with the atmosphere, a consumption portion for consuming the liquid flowing out from the second storage chamber of the tank, and a detection portion for detecting that the vertical position of the liquid level stored in the second storage chamber has reached 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. In a region 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 path.

[0008] In the above configuration, the predetermined position at which the detection unit detects the liquid level is below the opening of the tube and above the inlet of the tank. That is, the predetermined position is at the same height as the flow path. Therefore, in a state where the liquid level has reached the predetermined position due to the outflow of the liquid from the second storage chamber and is detected by the detection unit, the liquid level exists in the second storage chamber and the flow path.

[0009] Here, in the above configuration, above a 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 path. Therefore, in a state where the liquid level exists in both the second storage chamber and the flow path, the liquid level in the second storage chamber is difficult to drop. Thus, in a state where the liquid level reaches the predetermined position and is detected by the detection unit, it is highly likely that there is no liquid remaining in the first storage chamber that can be supplied to the second storage chamber. That is, it is possible to reduce the possibility of false detection where, in a state where there is sufficient liquid remaining in the first storage chamber, it is detected that there is no liquid remaining in the first storage chamber that can be supplied to the second storage chamber.

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

[0011] According to the above configuration, the position of the liquid level in the flow path is likely to change around the predetermined position in the vertical direction. Thereby, the time until the liquid level in the flow path and the liquid level in the second storage chamber become equal due to the head difference can be shortened.

[0012] (3) The above second storage chamber has a first portion and a second portion above the above first portion and having a smaller horizontal cross-sectional area than the above first portion. The above inlet communicates with the above first portion. The above detection unit detects the liquid level of the liquid stored in the above 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] Also, according to the above configuration, the predetermined position is in the second portion rather than the first portion, and the horizontal cross-sectional area of the second portion is smaller than the horizontal cross-sectional area of the first portion. That is, the detection unit detects the liquid level in the second portion with a small horizontal cross-sectional area. Therefore, the detection accuracy by the detection unit can be increased compared to the case where the predetermined position is in the first portion.

[0015] (4) The second storage chamber has a third portion that is above the second portion and has 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 and a light emitting unit that irradiates light toward the prism in the second storage chamber.

[0018] (6) For example, the detection unit includes a light emitting unit that irradiates light, and a float provided in the second storage chamber and having a specific gravity smaller than that of the liquid stored in the second storage chamber. When the vertical position of the liquid level in the second storage chamber reaches the predetermined position, the detection member moves from one of the positions on the optical path of the light irradiated by the light emitting unit or a position deviated from the optical path to the other.

[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 the liquid stops flowing from the first storage chamber of the cartridge through the inlet into the second storage chamber of the tank, the liquid that is below the inlet and above the outlet in the second storage chamber can be supplied to the consumption unit.

[0021] (8) The pipe extends in the vertical direction. 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 path is likely to change. Thereby, the time until the liquid level in the flow path becomes equal to the liquid level in the second storage chamber due to the head difference can be shortened.

Advantages of the Invention

[0023] According to the present invention, the possibility of misdetection of the remaining liquid amount can be reduced.

Brief Description of the Drawings

[0024]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0025] Hereinafter, embodiments of the present invention will be described. It should be noted that the embodiments described below are merely examples of the present invention, and it goes without saying that the embodiments of the present invention can be appropriately changed without changing the gist of the present invention. Also, with reference to the posture in which the multifunction machine 10 is installed horizontally so as to be usable (the posture in FIG. 1, which may be referred to as the "use posture"), the vertical direction 7 is defined. With the direction in which the sheet 12 is fed from the feed tray 15 of the multifunction machine 10 as the rear, the front-rear direction 8 is defined, and the left-right direction is defined when the multifunction machine 10 is viewed from the front. In FIGS. 1 to 7, the direction toward the back of the paper surface is the right direction. In the present embodiment, in the use posture, the vertical 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 Multifunction Machine 10] The multifunction machine 10 (an example of a system) has a printer unit 11 that records an image on a sheet 12 by an inkjet recording method. Also, the multifunction machine 10 may have various functions such as a facsimile function, a scan function, and a copy 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 conveyance rollers 25, a pair of discharge rollers 27, a recording unit 24, and a platen 26.

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

[0028] [Conveyance Path 17] The conveyance path 17 refers to the space formed by the guide members 18 and 19, the recording unit 24, the platen 26, and the like. The guide members 18 and 19, the recording unit 24, and the platen 26 face each other at a predetermined interval inside the printer unit 11. The conveyance path 17 is a path that extends upward from the rear end of the feed tray 15, makes a U-turn, and reaches the discharge tray 16 via a position facing the recording unit 24. The conveyance direction is indicated by the dashed-dotted arrow in FIG. 1.

[0029] [Conveying roller pair 25] The conveying roller pair 25 is disposed in the conveyance 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 is rotated along with the rotation of the conveying roller 25A. The sheet 12 is sandwiched between the conveying roller 25A and the pinch roller 25B that rotate forward by the transmission of the forward driving force of the motor, and is conveyed along the conveyance direction.

[0030] [Discharge roller pair 27] The discharge roller pair 27 is disposed downstream of the conveying roller pair 25 in the conveyance direction in the conveyance path 17. The discharge roller pair 27 includes a discharge roller 27A and a flapper 27B that face each other. The discharge roller 27A is driven by a motor (not shown). The flapper 27B is rotated along with the rotation of the discharge roller 27A. The sheet 12 is sandwiched between the discharge roller 27A and the flapper 27B that rotate forward by the transmission of the forward driving force of the motor, and is conveyed along the conveyance direction.

[0031] [Recording unit 24, platen 26] The recording unit 24 (an example of a consumption unit) and the platen 26 are disposed between the conveying roller pair 25 and the discharge roller pair 27 in the conveyance direction as shown in FIG. 1. More specifically, the recording unit 24 and the platen 26 are disposed downstream of the conveying roller pair 25 in the conveyance direction and upstream of the discharge roller pair 27 in the conveyance direction. Further, the recording unit 24 and the platen 26 are disposed to face each other in the vertical 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 when the driving force of a motor (not shown) is transmitted thereto. A plurality of nozzles 29 are formed on the lower surface 28 of the recording head 21. The recording head 21 discharges ink droplets from the nozzles 29 by vibrating a vibration element such as a piezo - element. In the process of the carriage 22 moving, an image is recorded on the sheet 12 by the recording head 21 selectively discharging ink droplets onto the sheet 12 supported by the platen 26.

[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 the ink (an example of a liquid) stored in each ink cartridge 30 (an example of a cartridge) mounted on the tank 103 to the recording head 21. The ink tube 20 is a bundle of four tubes through which inks of respective colors (black, magenta, cyan, yellow) flow. The flexible flat cable electrically connects the control board that controls the operation of the multifunction machine 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] As shown in FIG. 2, the tank 103 has a box shape having a storage chamber 121 (an example of a second storage chamber) for storing ink inside. 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, 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 in front of the first front wall 152A and extends upward from the lower wall 154. The third front wall 152C is between the first front wall 152A and the second front wall 152B in the vertical direction 7 and is located behind 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 and the upper end of the third front wall 152C. The step wall 157 connects the upper end of the second front wall 152B and the lower end of the third front wall 152C.

[0037] Among the walls constituting the tank 103, at least the portion constituting the prism 55A of the liquid level sensor 55, which will be described later, formed on the rear wall 151 has translucency that allows the 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 the rear wall 151, the front wall 152, the upper wall 153, the 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 the portion of the storage chamber 121 below the broken line 131 shown in FIG. 2. The first portion 161 is partitioned by the rear wall 151, the second front wall 152B, the step wall 157, the lower wall 154, and a pair of side walls 155.

[0040] The second portion 162 is the portion of the storage chamber 121 between the broken line 130 and the broken line 131 shown in FIG. 2. The second portion 162 is partitioned 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 part 163 is the part of the storage chamber 121 above the dashed line 130 shown in FIG. 2. The third part 163 is partitioned by the rear wall 151, the first front wall 152A, the stepped wall 156, the upper wall 153, and the pair of side walls 155. The third part 163 is located above the second part 162.

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

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

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

[0045] The first part 161 of the storage chamber 121 communicates with the ink tube 20 through the outlet 128. The outlet 128 is formed near the lower wall 154 that partitions the lower end of the storage chamber 121. The outlet 128 is located below the connecting tube 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 air communication part) is formed in the upper wall 153. The communication port 124 penetrates the upper wall 153. Through the communication port 124, the third part 163 of the storage chamber 121 communicates with the outside (atmosphere) of the tank 103. Note that the communication port 124 may be blocked by a semipermeable membrane.

[0047] [Connection pipe 107] As shown in FIG. 2, a connection pipe 107 (an example of a pipe) extends upward from the step wall 157. That is, the connection pipe 107 extends in the vertical direction 7. The connection pipe 107 is disposed at a position corresponding to the ink supply part 34 of the ink cartridge 30 mounted on the multifunction machine 10.

[0048] The connection pipe 107 is made of a tubular resin. An opening 109 is formed at the protruding tip of the connection pipe 107. Further, an inlet 126 is formed in the step wall 157. The inlet 126 is below the opening 109 and above the outlet 128. The inlet 126 communicates the internal space 107A (an example of a flow path) of the connection pipe 107 with the first part 161 of the storage chamber 121.

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

[0050] [Liquid level sensor 55] The liquid level sensor 55 (an example of a detection part) detects that the liquid level of the ink in the storage chamber 121 has reached the predetermined position P1 by using a prism 55A having different reflectivities depending on whether or not the ink is in contact.

[0051] The predetermined position P1 is, in the vertical direction 7, a position below the opening 109 of the connecting pipe 107 and above the inflow port 126. In the present embodiment, the predetermined position P1 is, in the vertical direction 7, the position of the second portion 162 of the storage chamber 121 of the tank 103. 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 portion 55B, and a light receiving portion (not shown). Among the rear walls 151 that partition the first portion 161 of the storage chamber 121, the portion extending over the predetermined position P1 and its vicinity constitutes the prism 55A. The light emitting portion 55B and the light receiving portion are arranged to face the prism 55A behind the prism 55A. The light emitting portion 55B irradiates light toward the prism 55A. The light receiving portion receives the light irradiated from the light emitting portion 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 liquid level of the ink stored in the storage chamber 121 is higher than the predetermined position P1, ink contacts the prism 55A on the optical path of the light irradiated from the light emitting portion 55B. At this time, the light irradiated from the light emitting portion 55B to the prism 55A enters the storage chamber 121 through the prism 55A and thus does not reach the light receiving portion. At this time, the light receiving portion outputs a low-level signal to the control board. On the other hand, when the liquid level of the ink stored in the storage chamber 121 is below the predetermined position P1, ink does not contact the prism 55A on the optical path of the light irradiated from the light emitting portion 55B. At this time, the light irradiated from the light emitting portion 55B to the prism 55A is reflected by the prism 55A and reaches the light receiving portion. At this time, the light receiving portion outputs a high-level signal to the control board.

[0054] After receiving a low-level signal from the liquid level sensor 55 and then a high-level signal, the controller mounted on the control board, for example, notifies that the ink stored in the storage chamber 32 of the ink cartridge 30 described in detail below cannot be supplied to the tank 103. As a notification method, for example, it notifies the user through a display or the like of the multifunction device 10. That is, 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 the 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 has a substantially rectangular parallelepiped shape. Note that the outer shapes of the respective ink cartridges 30 in which different colors of ink are stored may be the same or different. The housing 31 is composed of a rear wall 40, a front wall 41, an upper wall 39, a lower wall 42, and a pair of side walls 37 facing 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) for storing ink.

[0056] The ink supply unit 34 protrudes downward from near the front end of the lower 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 lower wall 42. The protruding end of the ink supply unit 34 opens to the outside of the ink cartridge 30. Although not shown in each figure, 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 air communication portion) is formed in the upper wall 39. The communication port 35 penetrates the upper wall 39 of the housing 31. Through the communication port 35, the storage chamber 32 communicates with the outside (atmosphere) of the ink cartridge 30. Note that the communication port 35 may be blocked by a semipermeable membrane.

[0058] As shown in FIG. 2, the ink cartridge 30 is connected to the tank 103 from above. Specifically, the connection pipe 107 of the tank 103 is inserted downward into the internal space of the ink supply unit 34 of the ink cartridge 30, whereby the ink supply unit 34 of the ink cartridge 30 and the connection pipe 107 of the tank 103 are connected. That is, the ink cartridge 30 is connected to the connection pipe 107 along the vertical direction 7.

[0059] In a state where the ink cartridge 30 and the tank 103 are connected, the ink stored in the storage chamber 32 of the ink cartridge 30 flows into the internal space 107A of the connection pipe 107 through the opening 109 of the connection pipe 107 of the tank 103. 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. As described above, in a state where 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 connection pipe 107.

[0060] The posture of the multifunction machine 10 shown in FIG. 2 is the use posture. In the use posture, various operations such as image recording are executed. Hereinafter, the process in which the ink stored in the storage chamber 32 of the ink cartridge 30 and the storage chamber 121 of the tank is consumed by the execution of image recording and the detection by the liquid level sensor 55 is described.

[0061] When the ink cartridge 30 is mounted on the cartridge mounting portion 110, since ink can flow between the storage chamber 32 and the storage chamber 121, 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 executed, the ink stored in the storage chambers 32 and 121 flows out from the outlet 128 to the recording head 21. At this time, the amount of ink flowing out from the storage chamber 32 and the amount of ink flowing out from the storage chamber 121 are not necessarily equal. Therefore, the liquid level of one of the storage chambers 32 and 121 may temporarily become lower than the liquid level of the other of the storage chambers 32 and 121. However, as time passes, the liquid level of the storage chamber 32 and the liquid level of the storage chamber 121 become equal due to the head difference. In this way, due to the consumption of ink by the execution of image recording, the liquid levels of the storage chambers 32 and 121 decrease. Then, the lowered liquid levels come to be located in the internal space 107A of the connecting pipe 107 and the second portion 162 of the storage chamber 121. The liquid level at this time is indicated by a one-dot chain line in FIG. 2 as the position P6.

[0063] When image recording is executed in the state where the liquid level is at the position P6, the ink stored in the storage chambers 32 and 121 is consumed. Due to this consumption, when the liquid level of the second portion 162 of the storage chamber 121 drops to a predetermined position P1, the liquid level sensor 55 outputs a high-level signal to the controller. The controller that has received the high-level signal notifies that the ink stored in the storage chamber 32 of the ink cartridge 30 cannot be supplied to the tank 103.

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

[0065] [Operation and Effect of the Present Embodiment] According to this embodiment, the predetermined position P1 where the liquid level sensor 55 detects the liquid level is below the opening 109 of the connection pipe 107 and above the inlet 126 of the tank 103. That is, the predetermined position P1 is at the same height as the internal space 107A of the connection pipe 107. Therefore, in a state where the liquid level becomes 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 the storage chamber 121 and the internal space 107A.

[0066] Here, in this embodiment, above the predetermined position P1 and below the opening 109, the horizontal cross-sectional area of the storage chamber 121 is larger than the horizontal cross-sectional area of the internal space 107A of the connection pipe 107. Therefore, in a state where the liquid level exists in the storage chamber 121 and the internal space 107A, the liquid level in the storage chamber 121 is difficult to drop. Thus, in a state where the liquid level becomes the predetermined position P1 and is detected by the liquid level sensor 55, it is highly likely that there is no ink remaining in the storage chamber 32 that can be supplied to the storage chamber 121. That is, it is possible to reduce the possibility of false detection such that in a state where there is sufficient ink remaining in the storage chamber 32, it is detected that there is no ink remaining in the storage chamber 32 that can be supplied to the storage chamber 121.

[0067] Also, according to this embodiment, since the internal space 107A extends in the vertical direction 7 around the predetermined position P1 in the vertical direction 7, the position of the liquid level in the internal space 107A is likely to change. Thereby, the time until the liquid level in the internal space 107A becomes equal to the liquid level in the storage chamber 121 due to the head difference can be shortened.

[0068] Also, according to this embodiment, even after 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 runs out, a large amount of ink remains in the first portion 161 of the storage chamber 121. And the ink remaining in the first portion 161 can be supplied to the recording unit 24.

[0069] Further, according to the present embodiment, the predetermined position P1 is in the second portion 162 instead of the first portion 161, and the horizontal cross-sectional area of the second portion 162 is smaller than that of the first portion 161. That is, the liquid level sensor 55 detects the liquid level in the second portion 162 having a small horizontal cross-sectional area. Therefore, the detection accuracy by the liquid level sensor 55 can be higher than the case where the predetermined position P1 is in the first portion 161.

[0070] Further, according to the present 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] Further, according to the present embodiment, the outlet 128 is located below the inlet 126. Therefore, even after the ink stops flowing from the storage chamber 32 of the ink cartridge 30 into the storage chamber 121 of the tank 103 through the inlet 126, the ink in the storage chamber 121 that is below the inlet 126 and above the outlet 128 can be supplied to the recording unit 24.

[0072] Further, according to the present embodiment, since the connecting pipe 107 extends in the vertical direction 7, the position of the liquid level in the internal space 107A of the connecting pipe 107 is likely to change. Thereby, the time until the liquid level in the internal space 107A becomes equal to the liquid level in the storage chamber 121 due to the head difference can be shortened.

[0073] [Modification Example] In the above embodiment, the liquid level sensor 55 uses the prism 55A. However, other known configurations may be adopted for the liquid level sensor 55.

[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 detected member 55C disposed 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, in the storage chamber 121, the float 61 generates buoyancy in a state of being present in the ink. The arm 62 extends upward from the float 61. The 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 lower part.

[0076] The light emitting part 55B and the light receiving part are arranged to face each other with the tank 103 interposed therebetween in the left - right direction. The light emitting part 55B irradiates light toward the light receiving part. The light receiving part receives the light irradiated from the light emitting part 55B and outputs a signal based on the intensity of the received light to the control board. In order to shorten the distance in the left - right direction between the light emitting part 55B and the light receiving part and ensure that the light reaches the light receiving part from the light emitting part 55B, the length of the tank 103 in the left - right direction at the portion between the light emitting part 55B and the light receiving part may be configured to be shorter than the length of the tank 103 in the left - right direction at other portions.

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

[0078] When the liquid level of the ink stored in the storage chamber 121 drops below the predetermined position P1, the float 61 descends together with the liquid level. As a result, the detected member 55C rotates to the second position shown by the dashed line in FIG. 3. At this time, the tip 62A of the arm 62 is at a position retracted from between the light emitting part 55B and the light receiving part in the left - right direction, that is, a position deviated from the optical path of the light irradiated by the light emitting part 55B. Therefore, the light irradiated from the light emitting part 55B reaches the light receiving part. At this time, the light receiving unit outputs a high-level signal to the control board.

[0079] Also, for example, as the liquid level sensor 55, an electrode rod inserted into the storage chamber 121 may be adopted. In this case, two electrode rods are arranged in the storage chamber 121. The two electrode rods are mounted on a substrate (not shown). One lower end of the two electrodes is at a position slightly higher than a predetermined position P1. The other lower end of the two electrodes is located below the predetermined position P1. Then, based on whether or not a current flows between the two electrodes through the ink, it is detected 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 the tank 103 is not limited to that shown in FIG. 2 as long as the upper end of the storage chamber 121 is above the internal space 107A of the connection pipe 107, the lower end of the storage chamber 121 is below the internal space 107A of the connection pipe 107, and the horizontal cross-sectional area of the storage chamber 121 is larger than the horizontal cross-sectional area of the internal space 107A above the predetermined position P1 and below the opening 109. It may have various configurations as described below.

[0081] In the above embodiment, the connection 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 connection 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 connection pipe 107 along the vertical direction 7, but it may be connected to the connection pipe 107 along a direction other than the vertical direction 7 (for example, the front-rear direction 8).

[0082] For example, as shown in FIG. 4, when the ink cartridge 30 and the tank 103 are configured such that the ink cartridge 30 is connected to the tank 103 from the front, the connection pipe 107 of the tank 103 may include a vertical portion 107B extending in the vertical direction 7 and a horizontal portion 107C extending in the front-rear direction 8. In the case where the connection pipe 107 includes the vertical portion 107B, the predetermined position P1 is 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 FIG. 4, a part of the connection pipe 107 is the vertical portion 107B, while in the above-described embodiment (the configuration shown in FIG. 2), the entire connection pipe 107 is a vertical portion.

[0083] In the above-described embodiment, the predetermined position P1 was in the second portion 162. That is, the liquid level sensor 55 detected the liquid level of the second portion 162. Therefore, the prism 55A of the liquid level sensor 55 in the above-described embodiment and the detected member 55C of the liquid level sensor 55 in the above-described modification were formed in the second portion 162. However, the predetermined position P1 may be outside the second portion 162. That is, the liquid level sensor 55 may detect the liquid level outside the second portion 162.

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

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

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

[0087] The tank 103 does not necessarily have to be in a shape having all of the first portion 161, the second portion 162, and the third portion 163 as shown in FIG. 2. For example, as shown in FIG. 7(A), the tank 103 may have only the first portion 161 and the second portion 162 and not have the third portion 163. In the case of the configuration shown in FIG. 7(A), the second portion 162 is partitioned by the rear wall 151, the third front wall 152C, the upper wall 153, and the pair of side walls 155. Also, for example, as shown in FIG. 7(B), the tank 103 may simply be in a rectangular parallelepiped shape.

[0088] In the above-described embodiment, the communication port 124 was formed in the upper wall 153. However, the communication port 124 may be formed not only in the upper wall 153 but also, for example, in the first front wall 152A.

[0089] In the above-described embodiment, the communication port 35 was formed in the upper wall 39. However, the communication port 35 may be formed not only in the upper wall 39 but also, for example, in the front wall 41.

[0090] In the above-described embodiment, ink was described as an example of a liquid, and the recording unit 24 was described as an example of a consumption unit. However, the present invention is not limited thereto. For example, when the present invention is applied to an apparatus that applies a pretreatment liquid to a sheet or the like by a roller prior to ink during printing, the pretreatment liquid is an example of a liquid, and the roller is an example of a consumption unit.

Explanation of Reference Numerals

[0091] 10 ··· Multifunction machine (system) 24 ··· Recording unit (consumption unit) 30··· Ink cartridge (Cartridge) 32··· Storage chamber (First storage chamber) 35··· Communication port (First air communication part) 55··· Liquid level sensor (Detection part) 103··· Tank 107··· Connecting pipe (Pipe) 107A··· Internal space 109··· Opening 121··· Storage chamber (Second storage chamber) 124··· Communication port (Second air communication part)

Claims

1. A system comprising: a tank having a pipe with an opening and a flow path through which a liquid can flow, and a storage chamber to which liquid is supplied from the pipe; and a consumption unit that consumes the liquid supplied from the storage chamber of the tank, The storage chamber has a first portion including an inlet through which liquid flowing through the flow path of the tube flows in and an outlet through which the liquid flows out to the consumption section, and a second portion located above the inlet and supplying liquid to the first portion, The tank has an atmosphere communication part that communicates the storage chamber with the atmosphere, the tank has a detection unit that detects when a vertical position of a liquid level of the second portion reaches a predetermined position above the inlet and below the opening of the pipe, When liquid is flowing into the consumption section, the liquid level above the predetermined position continues to fall even if it falls below the predetermined position, A system in which the horizontal cross-sectional area of ​​the second portion above the predetermined position is greater than the horizontal cross-sectional area of ​​the flow path.

2. A system comprising: a tank having a pipe with an opening and a flow path through which liquid can flow, and a storage chamber to which liquid is supplied from the pipe; and a consumption unit that consumes the liquid supplied from the storage chamber of the tank, The storage chamber has a first portion including an inlet through which liquid flowing through the flow path of the tube flows in and an outlet through which the liquid flows out to the consumption section, a second portion located above the inlet and supplying liquid to the first portion, and a third portion located above the second portion and supplying liquid to the second portion, The horizontal cross-sectional area of ​​the third portion is greater than the horizontal cross-sectional area of ​​the second portion; the tank has a detection unit that detects when a vertical position of a liquid level of the third portion reaches a predetermined position that is above the inlet and below the opening of the pipe, A system in which the horizontal cross-sectional area of ​​the third portion above the predetermined position is greater than the horizontal cross-sectional area of ​​the flow path.

3. A system as described in claim 2, wherein the third portion has a portion above the opening of the tube, and the portion above the opening has an opening communicating with the atmosphere.

4. The system described in claim 2, characterized in that the detection unit arranged in the third part is arranged directly above the second part.

5. The system described in claim 2, characterized in that the third portion extends horizontally in the direction in which the outlet is located further than the second portion.

6. A system described in at least one of claims 1 or 2, characterized in that the tube and the second part are connected only via the first part.

7. The tube extends upward from an upper surface of the first portion of the storage chamber, 3. The system of claim 1 or claim 2, wherein the second portion extends upwardly from a top surface of the first portion of the reservoir.

Images