JP2016175377A - Liquid consuming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid consuming device capable of using an electrode in common irrespective of a difference in ink tank capacity and accurately detecting the reduction of an ink residual amount.SOLUTION: A printer 110 includes an ink consumption amount calculation part 42 for calculating the consumption amount of each ink, a determination information storage part 53 for storing the determination information of each ink, an electrode 15 and an electrode 16 for detecting whether each ink is at a predetermined height, a liquid surface reduction determination part 43 for determining whether the ink is at a predetermined height, and an ink residual amount determination part 44 for determining the residual state of each ink. At least two of a plurality of ink tanks 11 are different from each other in capacity, the predetermined heights are set equal to each other. The ink residual amount determination part 44 determines the residual state of the ink based on the ink consumption amount calculated by the ink consumption amount calculation part 42 and the determination information after the liquid surface reduction determination part 43 determines that the ink is not at the predetermined height.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a liquid consuming apparatus.

  As an example of a liquid consuming apparatus, an ink jet printer (hereinafter simply referred to as a printer) is known. In a printer, ink, which is an example of liquid, is stored in an ink tank (or ink cartridge), which is an example of a liquid container, and printing is performed by ejecting ink from a jet head onto a print medium such as print paper. Can do. In such a printer, a printer having a function of issuing a warning by detecting a decrease in the remaining amount of ink in the ink tank is proposed in order to avoid an empty shot state in which ink is consumed and ink to be ejected is lost. (For example, refer to Patent Document 1).

  In the printer described in Patent Document 1, after detecting that the electrode provided in the ink tank (ink cartridge) is immersed in ink, the remaining ink counter starts calculating (counting) the ink consumption. . When the remaining ink detector detects that the ink level has dropped, the ink consumption calculated by the remaining ink counter is compared with a predetermined value, and the ink consumption is a predetermined value. Alerts the user that the ink level is low when exceeding. Note that Patent Document 1 does not describe a configuration including a plurality of ink tanks having different capacities.

  On the other hand, there is an ink jet printer in which the ejection amount and supply amount per unit time of a specific color (for example, black) ink among a plurality of color inks are set higher than those of other color inks. It has been proposed (see, for example, Patent Document 2). In the printer described in Patent Document 2, the consumption amount of the ink of the specific color is larger than the consumption amount of the other ink, so the capacity of the ink tank that stores the ink of the specific color is increased. It is desirable to make it larger than the capacity of the tank. In addition, it is desirable that a printer with different ink tank capacities has a function of issuing a warning by detecting a decrease in the remaining amount of ink in the ink tank, as in the printer described in Japanese Patent Application Laid-Open No. 2005-228561.

JP-A-8-34123 JP 2001-260382 A

  By the way, when the capacities of the ink tanks are different, for example, there is a configuration in which the ink tanks having different capacities have the same height and have different widths or depths (that is, horizontal cross-sectional areas). When a printer including an ink tank having such a configuration is added with a function for detecting a decrease in the remaining amount of ink with an electrode as described in Patent Document 1, the following problems arise.

  If the electrodes are provided at the same height for a plurality of ink tanks having different capacities (cross-sectional areas in the horizontal direction), the height at which the drop in the ink level is detected is the same for each ink tank. The remaining amount of ink at the time of detection differs depending on the capacity of the ink tank. Therefore, if it is attempted to make the remaining amount of each ink the same when the ink level drop is detected between the ink tanks having different capacities, the length of the electrode and the length of the electrode are changed according to the difference in the capacity (cross-sectional area) of the ink tank. It is necessary to vary the height at which the electrodes are provided, which increases the types of components such as the electrodes and the detection substrate, and complicates the arrangement. If a predetermined value to be compared with the ink consumption is uniformly set for a plurality of ink tanks having different capacities (different ink consumption), the ink remaining amount drop is accurately detected. It becomes difficult.

  Therefore, in a printer that individually stores different types of ink in a plurality of ink tanks having different capacities, the remaining ink in each ink tank is avoided while avoiding an increase in the types of components such as electrodes and detection boards and a complicated arrangement. There is a need for a printer that can more accurately detect a decrease in the amount and suppress the risk of idle shots.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A liquid consuming apparatus according to this application example is a liquid consuming apparatus that individually stores a plurality of different types of liquids in a plurality of liquid containers and consumes the plurality of liquids. A calculation unit that calculates the consumption amount of each liquid, a first storage unit that stores determination information for determining the remaining state of each liquid set for each liquid container, and each liquid container A pair of conductive members for detecting whether or not each liquid is present at a predetermined height from the bottom surface of each liquid container, and an output from the pair of conductive members for each liquid container A first determination unit that determines whether or not each liquid is at the predetermined height based on a signal; and a second determination unit that determines a remaining state of each liquid for each of the liquid containers. And at least two of the plurality of liquid containers The capacities are different from each other, and the predetermined height detected by the pair of conductive members is set to the same height for each of the liquid containers, and the second determination unit is the first determination unit. After determining that there is no liquid at the predetermined height with respect to any one of the plurality of liquid containers, the calculation unit calculates the liquid for the one liquid container. The remaining state of the liquid is determined based on the consumption amount and the determination information set for the one liquid container.

  According to the configuration of the application example, when the liquid level is lower than a predetermined height in any one of the plurality of liquid containers, the first determination unit is based on the output signals from the pair of conductive members. Determines that the remaining amount of liquid in the liquid container has decreased. In the liquid container, when the liquid is further consumed after the determination by the first determination unit, the second determination unit determines whether the liquid is based on the liquid consumption calculated by the calculation unit and the determination information. The remaining state is determined. Here, the liquid consumption is calculated for each liquid container, and the determination information is set for each liquid container. Therefore, even if the remaining amount of liquid in each liquid container when the first determination unit determines that there is no liquid at a predetermined height is different depending on the size of the liquid container, By appropriately setting the determination information, it is possible to determine the remaining state of each liquid more accurately regardless of the difference in the capacity of the liquid container. Therefore, in a liquid consuming apparatus that stores a plurality of liquids of different types in a plurality of liquid containers having different capacities, the remaining amount of each liquid can be more accurately reduced while avoiding an increase in the types of conductive members and the complexity of the arrangement. It is possible to suppress the risk of occurrence of empty strikes.

  Application Example 2 In the liquid consuming device according to the application example, the second determination unit is configured such that the first determination unit does not have the liquid at the predetermined height with respect to the one liquid container. After the determination, the post-determination consumption calculated by the calculation unit as the consumption of the liquid consumed after the determination with respect to the one liquid container, and the set for the one liquid container It is preferable to determine the remaining state of the liquid based on the determination information.

  According to the configuration of this application example, the determination of the remaining state of the liquid by the second determination unit is the consumption after determination calculated by the calculation unit for the liquid container determined to have no liquid at a predetermined height. And determination information set individually for the liquid container. Therefore, the liquid container in consideration of the remaining amount of liquid when the first determination unit determines that the remaining amount of liquid has decreased and the minimum amount of liquid to prevent idling are determined as the determination information. By appropriately setting each time, it is possible to more accurately determine the remaining state of each liquid regardless of the difference in the capacity of the liquid container, and to suppress the risk of occurrence of idling.

  Application Example 3 A liquid consuming device according to the application example, wherein the calculation unit updates the consumption amount of each liquid calculated for each liquid container to the latest value and stores the updated value each time. When the first determination unit determines that the liquid is present at the predetermined height for each liquid container, the consumption amount of each liquid calculated by the calculation unit is updated to the latest value each time. A third storage unit that stores the consumption amount after determination, the consumption value stored in the second storage unit, and the first determination unit configured to store the predetermined amount for each liquid container. It is preferable that the difference is a difference from the value of the consumption amount stored last in the third storage unit before it is determined that the liquid is not present at the height.

  According to the configuration of this application example, the post-determination consumption used for the determination of the remaining state of the liquid is the last before the first determination unit determines that there is no liquid at a predetermined height for each liquid container. The difference between the value of consumption when it is determined that there is a liquid and the latest value of consumption. Therefore, the post-judgment consumption is greater than the liquid consumption consumed from when the liquid level becomes lower than the predetermined height until the second determination unit determines the remaining state of the liquid. For this reason, the risk that the actual consumption amount increases more than the post-judgment consumption amount can be reduced, so that the risk of the occurrence of idle shots can be kept low.

  Application Example 4 In the liquid consuming device according to the application example, the determination information includes information about the liquid that can be consumed after the first determination unit determines that the liquid is not at the predetermined height. The predetermined value set for each liquid container includes a predetermined value as a quantity, and the predetermined value set for the liquid container having a larger capacity among the two liquid containers having different capacities is the smaller one. It is preferable that it is larger than the predetermined value set for the liquid container.

  According to the configuration of this application example, the predetermined value that is set as the amount of liquid that can be consumed after determining that there is no liquid at a predetermined height with respect to the liquid container having a larger capacity and larger liquid consumption is , Larger than a predetermined value set for the liquid container having a smaller capacity and a smaller amount of liquid consumption. That is, since the determination information (predetermined value) used for determining the remaining state of the liquid is set according to the capacity of the liquid container (consumption amount of the liquid), each of the liquid containers having different capacities It is possible to detect the decrease in the remaining amount of the liquid more accurately, and to suppress the risk of occurrence of idling.

  Application Example 5 In the liquid consuming device according to the application example, the plurality of liquids include black ink and color ink, and the black ink is stored in the liquid container having the larger capacity, It is preferable that the color ink is accommodated in a liquid container having a smaller capacity.

  According to the configuration of this application example, the black ink, which is generally consumed more than the color ink, is stored in the liquid container having the larger capacity, and therefore, compared with the case where the black ink is stored in the smaller liquid container. The period until the black ink disappears in the liquid container can be extended. Thereby, it is possible to suppress a risk that the black ink is emptied.

  Application Example 6 In the liquid consuming device according to the application example, the determination information includes a first predetermined value and a second predetermined value as the predetermined value, and the second determination unit includes: After the first determination unit determines that the liquid is not at the predetermined height with respect to the one liquid container, the post-determination consumption amount in the one liquid container is determined as the determination of the remaining state of the liquid. When the ink becomes equal to or greater than the first predetermined value, an ink near end for warning of a decrease in the remaining amount of the liquid is determined, and the post-determination consumption amount in the one liquid container is the second predetermined value. An ink end for warning that the liquid has run out is determined when the above becomes, and the second predetermined value is a value corresponding to the consumption amount of each liquid consumed in a predetermined period. Preferably set for each liquid container

  According to the configuration of this application example, when the post-determination consumption amount is equal to or greater than the first predetermined value, the second determination unit determines the ink near end and warns the user that the remaining ink amount is low. On the other hand, it is possible to prompt the user to refill the liquid container before the ink runs out, or to replace the liquid container (ink cartridge). The ink end is determined when the post-determination consumption amount is equal to or greater than a second predetermined value. The second predetermined value is a value corresponding to the consumption amount of each ink consumed in a predetermined period. Set every time. Therefore, for example, by setting a second predetermined value in consideration of a predetermined period necessary for obtaining replenishment ink or a replacement liquid container and ink consumption during that period, The risk of running out of ink can be kept low regardless of the difference in the capacity of the liquid container.

  Application Example 7 In the liquid consuming device according to the application example described above, the pair of conductive members arranged for each liquid container is electrically connected, and the current is passed between the pair of conductive members in each liquid container. A detection substrate for detecting a state, and the height of each liquid container is the same, and the liquid containers having different capacities are different in at least one of width and depth. The pair of conductive members arranged above may have a longitudinal direction, and the longitudinal direction may be arranged along the height direction of each liquid container downward from the detection substrate.

  According to the configuration of this application example, the detection substrate is arranged above the plurality of liquid containers having the same height and different at least one of width and depth, and each liquid container has a longitudinal direction downward from the detection substrate. A pair of conductive members are arranged along the height direction. Therefore, regardless of the difference in the capacity of the liquid container, it is possible to easily arrange the pair of conductive members in common.

  Application Example 8 In the liquid consuming apparatus according to the application example described above, the pair of conductive members arranged for each liquid container is electrically connected, and the current is passed between the pair of conductive members in each liquid container. A detection substrate for detecting a state, and the height of each liquid container is the same, and the liquid containers having different capacities are different in at least one of width and depth. The pair of conductive members may be disposed laterally, and the pair of conductive members may have a longitudinal direction, and the longitudinal direction may be disposed along the depth direction of each liquid container from the detection substrate toward the lateral side.

  According to the configuration of this application example, the detection substrate is arranged on the side of a plurality of liquid containers having the same height and different at least one of width and depth, and the longitudinal direction extends from the detection substrate to the side. A pair of conductive members are arranged along the depth direction of the liquid container. Therefore, since the pair of conductive members can be used at the same height regardless of the difference in capacity of the liquid container, the detection substrate can be easily arranged without complicating the shape.

  Application Example 9 In the liquid consuming device according to the application example, the plurality of liquid containers are fixed to the liquid consuming device, and the liquid is supplied from the outside into the liquid container. An injectable inlet may be provided.

  According to the configuration of this application example, since each liquid container is provided with an inlet that can inject ink from the outside, the user can replenish ink from the inlet when the remaining amount of ink decreases. it can.

  Application Example 10 In the liquid consuming device according to the application example, the plurality of liquid containers are detachably held from the liquid consuming device, and the pair of conductive members are attached to the liquid containers. It may be.

  According to the configuration of this application example, each liquid container to which a pair of conductive members is attached is detachably held. Therefore, when the remaining amount of ink decreases, the user can remove the liquid container (ink cartridge) from the ink container. Can be replaced with a liquid container (ink cartridge) filled with

1 is a perspective view illustrating a basic configuration of a printer system according to a first embodiment. 1 is a schematic configuration diagram of a printer according to a first embodiment. FIG. 2 is a schematic configuration diagram of an ink supply unit according to the first embodiment. FIG. 2 is a schematic configuration diagram of an ink supply unit according to the first embodiment. 6 is a flowchart showing a method for determining the remaining state of ink according to the first embodiment. FIG. 9 is a schematic configuration diagram of an ink supply unit according to a second embodiment.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings. The drawings to be used are appropriately enlarged, reduced or exaggerated so that the part to be described can be recognized. In addition, illustrations of components other than those necessary for the description may be omitted.

(First embodiment)
<Basic configuration of printer system>
A basic configuration of a printer system including an ink jet printer (hereinafter simply referred to as a printer) as a liquid consuming apparatus according to the first embodiment will be described with reference to FIG. FIG. 1 is a perspective view illustrating a basic configuration of the printer system according to the first embodiment. The printer system 100 according to the first embodiment is a multifunction machine including a printer 110 as a liquid consuming apparatus and a scanner 120.

  FIG. 1 shows a Y axis, an X axis orthogonal to the Y axis, and a Z axis orthogonal to the X axis and the Y axis. In each of the XYZ axes, the direction of the arrow indicates the + direction (positive direction), and the direction opposite to the direction of the arrow indicates the − direction (negative direction). In the use state, the printer system 100 is arranged on a horizontal plane defined by the X axis and the Y axis, and the + Y direction is the front of the printer system 100. The Z axis is an axis orthogonal to a horizontal plane, and the −Z direction is a vertically downward direction.

  As shown in FIG. 1, the printer system 100 includes a printer 110, a scanner 120, and an ink supply unit 10. The printer system 100 has an operation panel 111 on the front side.

  On the operation panel 111, for example, buttons for performing operations such as power ON / OFF of the printer system 100, printing by the printer 110, reading of an original by the scanner 120, operation states and warnings of the printer system 100, and the like are displayed. A display unit 47 for displaying is arranged. The operation panel 111 is also provided with a reset button that is pressed when the user refills ink into an ink tank 11 described later.

  The printer 110 can print on a printing medium P such as printing paper by ejecting ink as a liquid. The printer 110 has a case unit 112. The case part 112 constitutes the outer shell of the printer 110. An opening 113 is provided on the front side of the case portion 112. A paper cassette 114 is detachably attached to the case portion 112 in the opening 113. Above the paper cassette 114 (+ Z direction), a paper discharge tray 115 is provided to be extendable in the front-rear direction (+ Y direction and −Y direction).

  Although details will be described later, the X-axis direction (+ X direction and −X direction) is the main scanning direction HD of the printer 110, and the Y-axis direction (+ Y direction and −Y direction) is the sub-scanning direction VD of the printer 110. A plurality of print media P are stacked on the paper cassette 114. The print medium P placed on the paper cassette 114 is supplied to the inside of the case unit 112 one by one along the sub-scanning direction VD, printed by the printer 110, and then discharged along the sub-scanning direction VD. The paper is discharged from 116 and placed on a paper discharge tray 115.

  The scanner 120 is placed on the printer 110. The scanner 120 has a case unit 121. The case part 121 constitutes the outer shell of the scanner 120. The scanner 120 is a flat bed type, and includes a document table (not shown) formed of a transparent plate member such as glass, and an image sensor (not shown) such as an image sensor. The scanner 120 can read an image or the like recorded on a medium such as paper as image data via an image sensor.

  The scanner 120 includes an auto document feeder 122 at the upper end. The auto document feeder 122 can sequentially feed and read a plurality of stacked originals (sheets on which images and the like are recorded) one by one. The scanner 120 is configured to be rotatable with respect to the printer 110 and also has a function as a lid of the printer 110. The user can rotate the scanner 120 with respect to the printer 110 by inserting a finger into the handle portion 123 and lifting the scanner 120 upward. Thereby, the scanner 120 can be opened with respect to the printer 110.

  The ink supply unit 10 is disposed on the side of the printer 110. The ink supply unit 10 has a function of supplying ink IK (see FIG. 4B) as a liquid to the printer 110. The ink supply unit 10 includes a case unit 101. A plurality of ink tanks 11 as a plurality of liquid containers are arranged in the case portion 101, and a plurality of different types of ink IK are individually stored in the plurality of ink tanks 11. That is, the plurality of ink tanks 11 contain different types of ink IK for each ink tank 11.

  In this embodiment, there are four ink tanks 11a, 11b, 11c, and 11d. In the present embodiment, four types of inks are used, namely black ink and yellow, magenta, and cyan color inks. The ink tank 11a contains black ink IKa, and the ink tanks 11b, 11c, 11d contain color inks (yellow, magenta, cyan) inks IKb, IKc, IKd (FIG. 4B). )reference).

  The ink tanks 11 a, 11 b, 11 c, and 11 d are arranged so as to be aligned along the Y-axis direction from the front side of the printer 110, and are fixed in the case unit 101. Hereinafter, when the four ink tanks 11a, 11b, 11c, and 11d and the four types of inks IKa, IKb, IKc, and IKd are not distinguished, they are simply referred to as the ink tank 11 and the ink IK.

  In the present embodiment, each of the four ink tanks 11 is configured to be able to inject ink IK into the ink tank 11 from the outside. Therefore, the user can refill the ink tank 11 with the ink IK stored in another container. The detailed configuration of the ink tank 11 will be described later.

  The case portion 101 is provided with a window portion 102 corresponding to each of the four ink tanks 11. The window part 102 has optical transparency. Therefore, the user can visually recognize the four ink tanks 11 through the window portion 102. The window part 102 may be provided as an opening part formed in the case part 101, and may be comprised with the member which has a light transmittance.

  At least a part of the portion of each ink tank 11 that faces the window portion 102 has light transmittance. Therefore, the user can visually recognize the amount of ink IK in the four ink tanks 11 through the window portion 102. Each ink tank 11 is provided with an upper limit mark 17 at a portion facing the window portion 102. The upper limit mark 17 indicates the upper limit of the liquid level of the ink IK as a guide so as not to overflow from the ink tank 11 when the user injects the ink IK. Further, the user can grasp the amount of ink IK in each ink tank 11 using the upper limit mark 17 as a mark.

  In the present embodiment, the capacity of the ink tank 11a is larger than the capacity of the ink tanks 11b, 11c, and 11d. The capacities of the ink tanks 11b, 11c, and 11d are the same. It is assumed that the printer 110 consumes more black ink IKa than the color inks IKb, IKc, and IKd. Therefore, among the four ink tanks 11, the capacity of the ink tank 11a containing the black ink IKa is larger than the capacity of the ink tanks 11b, 11c and 11d containing the color inks IKb, IKc and IKd. . The ink tank 11a containing the black ink IKa is arranged on the front side of the printer 110 so that the user can easily grasp the remaining amount.

  In addition, the arrangement order from the front side of the ink tanks 11b, 11c, and 11d containing the color inks IKb, IKc, and IKd is not particularly limited. Further, when any of the other inks IKb, IKc, and IKd is consumed more than the black ink IKa, the ink IK may be accommodated in the ink tank 11a having a large capacity.

  A lid portion 103 is provided on the upper portion of the case portion 101. The lid portion 103 is rotatably engaged with the case portion 101 via the hinge portion 104. When the lid 103 is opened, the four ink tanks 11 are exposed. For example, when the user injects ink IK into the ink tank 11, the ink tank 11 can be accessed by rotating the lid 103 and opening it upward.

<Printer configuration>
Next, the configuration of the printer according to the first embodiment will be described with reference to FIG. FIG. 2 is a schematic configuration diagram of the printer according to the first embodiment. As shown in FIG. 2, the printer 110 according to the first embodiment includes a carriage 20, a paper feed motor 30, a carriage motor 33, a paper feed roller 34, a control unit 40, and a storage unit 50. ing. In FIG. 2, the scanner 120 is omitted.

  A print head 22 is mounted on the carriage 20. The print head 22 has a plurality of nozzles that open on the lower surface side of the carriage 20 and eject ink IK. A tube 18 is provided between the print head 22 and each ink tank 11. Each ink IK in the ink tank 11 is sent to the print head 22 via the tube 18. The print head 22 ejects each ink IK sent from the ink tank 11 as an ink droplet to the print medium P from a plurality of nozzles.

  The carriage 20 is connected to the control unit 40 by a cable (not shown). The carriage 20 reciprocates on the print medium P along the main scanning direction HD by being driven by the carriage motor 33. The paper feed motor 30 rotates the paper feed roller 34 and transports the print medium P in the sub-scanning direction VD. The ejection control of the print head 22 is performed by the control unit 40 via a cable.

  That is, in the printer 110, the control unit 40 controls the paper feed motor 30, the carriage motor 33, and the print head 22, so that the carriage 20 is conveyed in the sub-scanning direction VD while moving along the main scanning direction HD. Printing on the print medium P is performed by ejecting ink IK from the plurality of nozzles of the print head 22 to the print medium P to be printed.

  One end of the carriage 20 in the main scanning direction HD is a home position area in which the carriage 20 stands by. In the home position area, for example, a cap (not shown) for performing maintenance such as cleaning of the nozzles of the print head 22 is disposed. FIG. 2 shows a state where the carriage 20 is located at the home position.

  Further, a flushing box (not shown) for receiving flushing ink when performing flushing is provided at the other end portion (end portion opposite to the home position) of the carriage 20 in the main scanning direction HD. Has been placed. Note that flushing means that ink IK is ejected from each nozzle of the print head 22 during printing of the print medium P regardless of printing.

  An operation panel 111 including a display unit 47 is connected to the control unit 40. When the user operates the operation panel 111, the printer 110 and the scanner 120 can be operated by the control unit 40.

  For example, in FIG. 1, after setting a document on the auto document feeder 122 of the scanner 120, the user operates the operation panel 111 to start the operation of the printer system 100. Then, the original is read by the scanner 120. Subsequently, based on the read image data of the original, the printing medium P is fed from the paper cassette 114 into the printer 110 (case unit 112), and printing is performed on the printing medium P by the printer 110.

  Further, as shown in FIG. 2, a computer 49 can be connected to the control unit 40 via an interface (I / F) 48. The control unit 40 receives image data from the computer 49 via the interface 48, and controls the printer 110 (print head 22) to print the image on the print medium P.

  The control unit 40 includes a drive control unit 41, an ink consumption calculation unit 42 as a calculation unit, a liquid level decrease determination unit 43 as a first determination unit, and an ink remaining amount determination unit as a second determination unit. 44. The control unit 40 includes a CPU, a ROM, a RAM, and the like (not shown). For example, the control unit 40 operates as each unit of the control unit 40 when the control program stored in the ROM is expanded in the RAM and the CPU executes the control program expanded in the RAM.

  The drive control unit 41 controls the carriage motor 33 to move the carriage 20. As a result, the carriage motor 33 drives to move the print head 22 included in the carriage 20.

  The ink consumption calculation unit 42 calculates the ink consumption consumed by ejecting the ink IK from each nozzle of the print head 22.

  The ink consumption calculated by the ink consumption calculation unit 42 includes the ink consumption due to the cleaning and flushing of the nozzles of the print head 22 in addition to the ink consumption due to printing on the printing medium P. The ink consumption is a so-called soft count value. For example, based on the image data to be printed, the amount of ink IK ejected from the nozzles of the print head 22 (one dot) for each pass in which the carriage 20 reciprocates once. The amount of ink IK per hit x the number of ejected dots). Further, the amount of ink consumed when performing cleaning and flushing is calculated as the amount of each ink IK ejected from the nozzles of the print head 22 each time it is performed once.

  The liquid level lowering determination unit 43 determines whether each ink tank 11 has the ink IK at a predetermined height from the bottom surface. In the ink tank 11, an electrode 15 and an electrode 16 as a pair of conductive members described later are arranged for each ink tank 11 (see FIG. 4B). The liquid level lowering determination unit 43 determines whether there is ink IK at a predetermined height in each ink tank 11 based on the output signals from these electrodes 15 and 16.

  The determination by the liquid level lowering determination unit 43 is repeatedly performed at a predetermined timing. The predetermined timing is, for example, when the printer 110 (printer system 100) is turned on, when a print job is completed, or when a predetermined amount of ink IK is consumed during printing.

  The ink remaining amount determination unit 44 determines the ink consumption amount calculated by the ink consumption calculation unit 42 and the ink after the liquid level decrease determination unit 43 determines that the ink IK is not at a predetermined height for each ink tank 11. The remaining state of each ink IK is determined based on the determination information set for each tank 11.

  The determination of the ink remaining state includes “ink near end” indicating a state where the amount of ink IK in the ink tank 11 is low, and “ink end” indicating a state where the amount of ink IK in the ink tank 11 is almost exhausted. There is. The determination information is stored in a determination information storage unit 53 described later. The determination information includes a predetermined value A as a first predetermined value and a predetermined value B as a second predetermined value as predetermined values set for each ink tank 11.

  The remaining ink level determination unit 44 determines that the ink IK consumption in the ink tank 11 is predetermined after the liquid level decrease determination unit 43 determines that there is no ink IK at a predetermined height with respect to any of the ink tanks 11. When the value is equal to or greater than A, the ink near end is determined. For the ink tank 11 determined by the ink remaining amount determination unit 44 to be the ink near end, a warning for notifying the decrease in the remaining amount of the ink IK and prompting the replenishment of the ink IK is displayed on the display unit 47.

  After determining the ink near end, the ink remaining amount determination unit 44 determines the ink end when the consumption amount of the ink IK in the ink tank 11 exceeds a predetermined value B. When the ink remaining amount determination unit 44 determines that the ink end of any one of the ink tanks 11, the printing of the printer 110 is stopped in order to avoid an idle state in which the ejected ink IK is lost. Then, the ink tank 11 determined to be the ink end is notified that the ink IK has run out, and a warning for prompting replenishment of the ink IK is displayed on the display unit 47.

  The storage unit 50 stores information in a nonvolatile manner and rewritable. The storage unit 50 is configured by a nonvolatile memory such as an EEPROM, for example. The storage unit 50 includes a latest consumption storage unit 51 as a second storage unit, a detected consumption storage unit 52 as a third storage unit, and a determination information storage unit 53 as a first storage unit. including. The latest consumption amount storage unit 51, the detected consumption amount storage unit 52, and the determination information storage unit 53 may be configured by individual non-volatile memories, or may be divided into the same non-volatile memory. It may be configured as a separate area. In addition, the ROM provided in the control unit 40 may serve as the function of the storage unit 50.

  The latest consumption amount storage unit 51 stores the latest value of the accumulated value of the consumption amount of each ink IK calculated by the ink consumption amount calculation unit 42 for each ink tank 11. As described above, the ink consumption calculated by the ink consumption calculation unit 42 includes the ink consumption consumed by printing and the ink consumption consumed by cleaning and flushing. The ink consumption amount stored in the latest consumption amount storage unit 51 is updated to the latest value every time the ink consumption amount calculation unit 42 calculates the ink consumption amount. When the user refills the ink tank 11 with the ink IK and presses the reset button, the ink consumption amount stored in the latest consumption amount storage unit 51 for the ink tank 11 is cleared.

  In the detection consumption storage unit 52, when the liquid level lowering determination unit 43 determines that the ink IK is present at a predetermined height, the ink consumption calculation unit 42 stores the ink IK calculated for each ink tank 11. The latest value of cumulative consumption is stored. The ink consumption stored in the detected consumption storage unit 52 is updated to the latest value every time the liquid level lowering determination unit 43 determines that the ink IK is at a predetermined height, and once the liquid level lowering determination unit After 43 determines that there is no ink IK at a predetermined height, it is not updated.

  Therefore, for the ink tank 11 in which the liquid level lowering determination unit 43 determines that the ink IK is not at the predetermined height, the liquid level lowering determination unit 43 finally sets the ink IK to the predetermined height before the determination. The ink consumption amount when it is determined that there is is stored. When the user refills the ink tank 11 with the ink IK and presses the reset button, the ink consumption amount stored in the detection consumption amount storage unit 52 for the ink tank 11 is cleared.

  The determination information storage unit 53 stores determination information for the ink remaining amount determination unit 44 to determine the ink near end and the ink end for each ink tank 11. The determination information includes the predetermined value A and the predetermined value B described above. The predetermined value A and the predetermined value B are values set for each ink tank 11, that is, for each type of ink IK.

<Configuration of ink supply unit>
Next, the configuration of the ink supply unit according to the first embodiment will be described with reference to FIGS. 3 and 4. 3 and 4 are schematic configuration diagrams of the ink supply unit according to the first embodiment. Specifically, FIG. 3 is a perspective view of the ink supply unit, FIG. 4A is a plan view of the ink supply unit, and FIG. 4B is along the line AA ′ in FIG. It is sectional drawing. 3 and FIGS. 4A and 4B show a state where the case portion 101 is removed from the ink supply unit 10 shown in FIG.

  As shown in FIGS. 3 and 4A and 4B, the ink supply unit 10 includes four ink tanks 11a, 11b, 11c, and 11d, a holding unit 13, a detection substrate 14, and a pair of conductive members. The electrode 15 and the electrode 16 are provided.

  As shown in FIG. 3, the ink tanks 11a, 11b, 11c, and 11d are arranged in a line along the Y-axis direction. The ink tank 11 is made of a synthetic resin such as nylon or polypropylene, for example. Each of the four ink tanks 11 may be configured separately or may be configured integrally. When the ink tank 11 is integrally formed, the ink tank 11 may be formed integrally, or four ink tanks 11 formed separately may be bundled or connected together.

  In the present embodiment, the upper surface of the front (+ X direction) side portion of the ink tank 11 is lower than the upper surface of the rear (−X direction) side portion. An injection port 12 for injecting ink IK from the outside is provided on the upper surface of the front portion of the ink tank 11. When the user injects the ink IK stored in another container from the injection port 12, the ink tank 11 can be replenished with the ink IK of each color. Further, an upper limit mark 17 is provided on the front surface of the ink tank 11 to indicate a guide for the amount of ink when the user injects each ink IK.

  In the ink tank 11, the Z-axis direction, the Y-axis direction, and the X-axis direction are also referred to as a height direction, a width direction, and a depth direction, respectively. As described above, the capacity of the ink tank 11a that contains the black ink IKa is larger than the capacity of the ink tanks 11b, 11c, and 11d that contain the color inks IKb, IKc, and IKd. When the ink tank 11a and the ink tanks 11b, 11c, and 11d are compared, the height and depth are the same and the width is different. That is, the width (length in the Y-axis direction) of the ink tank 11a is larger than the width of the ink tanks 11b, 11c, and 11d.

  A holding portion 13 extending along the Y-axis direction in which the ink tanks 11a, 11b, 11c, and 11d are arranged is disposed above the portion on the rear side of the ink tank 11. The holding unit 13 is fixed to the four ink tanks 11 with screws or the like, for example. The holding unit 13 has a function of holding the detection substrate 14 disposed above the holding unit 13. The holding part 13 is made of, for example, an insulating synthetic resin. On the holding unit 13, a detection substrate 14 extending along the Y-axis direction in which the ink tanks 11a, 11b, 11c, and 11d are arranged is disposed. The detection substrate 14 is held by the holding unit 13.

  As shown in FIGS. 4A and 4B, a pair of electrodes 15 and 16 are electrically connected to the detection substrate 14 corresponding to each ink tank 11. The electrodes 15 and 16 are connected to the detection substrate 14 by, for example, a spring-like connector. A total of four pairs of electrodes 15 and electrodes 16 corresponding to the four ink tanks 11 are arranged along the extending direction of the detection substrate 14.

  As shown in FIG. 4B, a pair of electrodes 15 and electrodes 16 are arranged inside each ink tank 11. The electrode 15 and the electrode 16 have a longitudinal direction, and are arranged so that the longitudinal direction is along the height direction (Z-axis direction) of the ink tank 11 from the detection substrate 14 downward (−Z direction). The electrode 15 and the electrode 16 are made of a metal material such as stainless steel, for example.

  The electrode 15 has such a length that the lower end portion reaches a position close to the bottom surface of the ink tank 11. The electrode 16 is shorter than the electrode 15 and has a length such that the lower end portion reaches a position at a predetermined height from the bottom surface of the ink tank 11. The predetermined height from the bottom surface where the tip of the electrode 16 is located is set to the same height for the four ink tanks 11. The predetermined height is appropriately set based on, for example, the capacity of the ink tanks 11a, 11b, 11c, and 11d, the consumption amount of each ink IK during a predetermined period, and the like.

  The pair of electrodes 15 and 16 have a function of detecting whether or not the ink IK is present at a predetermined height in each ink tank 11. A voltage is applied between the electrode 15 and the electrode 16 through the detection substrate 14 from the control unit 40 (see FIG. 2). The voltage applied between the electrode 15 and the electrode 16 is preferably an AC voltage from the viewpoint of suppressing the precipitation of the ink IK.

  The detection board 14 is provided with an analog switch (not shown) for switching the ink tank 11 to which a voltage is applied. When the liquid level lowering determination unit 43 (see FIG. 2) determines whether or not the ink IK is at a predetermined height from the bottom surface, the ink tank 11 to be determined is selected by switching the analog switch. The A voltage is applied between the electrode 15 and the electrode 16 with respect to the selected ink tank 11.

  Focusing on the ink tank 11b in FIG. 4B, the height of the liquid level of the ink IKb accommodated in the ink tank 11b is equal to or higher than a predetermined height. That is, in the ink tank 11b, both the electrode 15 and the electrode 16 are immersed in the ink IKb. Therefore, in the ink tank 11b, a current flows between the electrode 15 and the electrode 16 through the ink IKb due to the applied voltage. Then, a detection circuit (not shown) provided on the detection board 14 outputs a signal indicating that there is an energization between the electrode 15 and the electrode 16 disposed in the ink tank 11b to the control unit 40. .

  As a result, the liquid level lowering determination unit 43 determines that the ink IKb is present at a predetermined height with respect to the ink tank 11b. Similarly, for the ink tank 11d in which the liquid level of the stored ink IKd is equal to or higher than a predetermined height, a current flows through the ink IKd between the electrode 15 and the electrode 16 when a voltage is applied. The liquid level lowering determination unit 43 determines that the ink IKd is present at a predetermined height.

  On the other hand, when paying attention to the ink tank 11a, the height of the liquid level of the ink IKa accommodated in the ink tank 11a is lower than a predetermined height. That is, in the ink tank 11a, the electrode 16 is not immersed in the ink IKa. Therefore, in the ink tank 11a, no current flows between the electrode 15 and the electrode 16 due to the applied voltage. As a result, the liquid level lowering determination unit 43 determines that there is no ink IKa at a predetermined height with respect to the ink tank 11a. Similarly, no current flows between the electrode 15 and the electrode 16 in the ink tank 11c in which the liquid level of the stored ink IKc is lower than the predetermined height. It is determined that there is no ink IKc.

  As described above, in this embodiment, whether or not the ink IK is present at a predetermined height from the bottom surface of the ink tank 11 is determined based on whether or not the electrode 15 and the electrode 16 are energized (difference in resistance value). Can be detected. The liquid level lowering determination unit 43 repeatedly determines whether the ink IK is present at a predetermined height from the bottom surface of each ink tank 11 at a predetermined timing. Therefore, the ink IK is consumed by repeating the printing by the printer 110, and when the liquid level lowering determination unit 43 performs the determination, the liquid level of the ink IK in any one of the ink tanks 11 is lower than a predetermined height. If it is determined that the ink tank 11 has no ink IK at a predetermined height.

  After the liquid level lowering determination unit 43 determines that there is no ink IK at a predetermined height, the ink level is further decreased by consuming the ink IK and is sent from the ink tank 11 to the print head 22 (see FIG. 2). If there is no more, it will be idle. In the present embodiment, in order to avoid the idling state, the remaining ink level determination unit 44 determines the remaining ink level in two stages, the ink near end and the ink end.

  Based on the determination result of the ink remaining amount determining unit 44, the control unit 40 notifies the user of a decrease in the remaining amount of ink by lighting the lamp on the operation panel 111 or displaying on the display unit 47, and the ink tank A warning is issued to prompt the user to replenish ink IK before the ink IK in 11 is exhausted.

  For example, the remaining amount of ink IK for determination in two stages of ink near end and ink end is set as follows. First, in order to reliably prevent the ink IK in the ink tank 11 from running out and causing the ink to run idle, the minimum remaining amount of ink IK that does not cause the ink ink to run for each ink tank 11 (hereinafter referred to as the minimum remaining amount). ) Is set. When the ink remaining amount determination unit 44 determines that the ink has ended, it is desirable that the minimum amount of ink IK be left in each ink tank 11.

  Next, to avoid going back to the idling state, it is necessary for the user to replenish the ink tank 11 with ink IK after the ink near end is determined and before the ink end is determined. . Although it is desirable that the refilling ink IK be prepared at the user's hand, it may be out of stock.

  Therefore, assuming a predetermined lead time (for example, one week) for the user to arrange the refilling ink IK, the consumption amount for each ink IK consumed during that period is estimated and calculated as the predetermined value B. . At the time when the ink remaining amount determination unit 44 determines that the ink near end has been reached, the ink IK of the total value of the above-mentioned minimum remaining amount and the predetermined value B (hereinafter referred to as the ink near end determination remaining amount) is stored in each ink tank 11. It is desirable to remain.

  On the other hand, when the liquid level lowering determination unit 43 determines that there is no ink IK at a predetermined height, the remaining amount of ink IK in each ink tank 11 (hereinafter referred to as the remaining amount at the time of liquid level lowering determination) It is obtained from the capacity of the tank 11 (cross-sectional area in the XY plane) and a predetermined height from the bottom surface where the tip of the electrode 16 is located. The predetermined value A is set as a value corresponding to the difference between the remaining amount at the time of liquid level reduction determination and the remaining amount at the time of ink near-end determination in each ink tank 11.

  When the ink near end is determined, the predetermined value A is the latest value calculated at the time of performing the ink near end determination and the calculated value of the consumption stored in the detection consumption storage unit 52 for each ink tank 11. It is compared with the consumption after the liquid level decrease determination (consumption after determination), which is the difference from the calculated value of the consumption stored in the consumption storage 51. That is, as the ink consumption when determining the ink near end, when the liquid level lowering determination unit 43 finally determines that the ink IK is at the predetermined height before determining that the ink IK is not at the predetermined height. A value calculated from the amount of ink consumed is used.

  Further, in the present embodiment, when determining the ink end, the consumption after the liquid level decrease determination described above is set as the ink consumption. That is, as the ink consumption when determining the ink end, when the liquid level lowering determination unit 43 finally determines that the ink IK is at the predetermined height before determining that there is no ink IK at the predetermined height. A value calculated from the amount of ink consumed is used. Therefore, when determining the ink end, the value of the consumption after the liquid level decrease determination is compared with the total value of the predetermined value A and the predetermined value B for each ink tank 11.

  The predetermined value A and the predetermined value B are stored in the determination information storage unit 53 as determination information for the ink remaining amount determination unit 44 to determine the ink near end and the ink end for each ink tank 11. ing.

  Here, as described above, the predetermined height for detecting the decrease in the liquid level of the ink IK is set to the same height with respect to the ink tanks 11a, 11b, 11c, and 11d. On the other hand, the width of the ink tank 11a that contains the black ink IKa is larger than the width of the ink tanks 11b, 11c, and 11d. That is, the cross-sectional area (bottom area) of the ink tank 11a in the XY plane is larger than the cross-sectional areas (bottom area) of the ink tanks 11b, 11c, and 11d. Accordingly, the remaining amount at the time of liquid level decrease determination of the ink IKa in the ink tank 11a is larger than the remaining amount at the time of liquid level decrease determination of the inks IKb, IKc, and IKd in the ink tanks 11b, 11c, and 11d.

  Note that if the ink tank 11a and the ink tanks 11b, 11c, and 11d are to have the same remaining amount at the time of liquid level determination, the length of the electrode 16 disposed in the ink tank 11a is set to the length of the ink tank 11b, 11c. , 11d. Therefore, the pair of electrodes 15 and 16 cannot be used in common for the four ink tanks 11.

  For example, if the printer system 100 is slightly inclined due to the installation location or the like, the ink tank 11a having a large bottom area has a remaining amount of ink IKa compared to the ink tanks 11b, 11c, and 11d having a small bottom area. Is the same as the remaining amount of the inks IKb, IKc, and IKd, there is a high risk that the supply of the ink IKa to the print head 22 is interrupted. Therefore, in this embodiment, the minimum remaining amount for the ink tank 11a is set to a value larger than the minimum remaining amount for the ink tanks 11b, 11c, and 11d.

  In this embodiment, it is assumed that the black ink IKa stored in the ink tank 11a is consumed more than the other inks IKb, IKc, and IKd. Therefore, in this embodiment, the predetermined value B for the ink tank 11a is set to a value larger than the predetermined value B for the ink tanks 11b, 11c, and 11d. The predetermined value A for the ink tank 11a is also set to a value larger than the predetermined value A for the ink tanks 11b, 11c, 11d.

  Thus, in the present embodiment, the remaining amount of ink IK can be detected more accurately than in the case where the predetermined value A and the predetermined value B are set uniformly between the ink tanks 11 having different capacities. Therefore, it is possible to more reliably suppress the idling state.

  In addition, by appropriately setting the predetermined value A according to the capacity of the ink tank 11 and the like, even if the remaining amount at the time of liquid level reduction is different between the ink tanks 11, it affects the detection accuracy of the remaining amount of the ink IK. There is no effect. Therefore, a common pair of electrodes 15 and 16 can be used in the ink tanks 11a and the ink tanks 11b, 11c, and 11d having different capacities, and the detection substrate 14 can be easily disposed.

<Method for determining remaining ink state>
Next, a method for determining the ink remaining state according to the present embodiment will be described. FIG. 5 is a flowchart illustrating a method for determining the remaining state of ink according to the first embodiment. The determination of the ink remaining state is executed by the control unit 40 at a predetermined timing such as every time when a predetermined amount of ink IK is consumed or every time the printer is turned on when the printer is turned on.

  Although not shown in FIG. 5, as described above, the latest value of the accumulated consumption amount of each ink IK calculated by the ink consumption amount calculation unit 42 for each ink tank 11 is the latest consumption amount storage unit 51. Is remembered. Further, when the liquid level lowering determination unit 43 determines that the ink IK is present at a predetermined height, the latest value of the accumulated consumption amount of each ink IK calculated by the ink consumption calculation unit 42 for each ink tank 11 is obtained. It is stored in the consumption storage unit 52 at the time of detection. The determination information storage unit 53 stores a predetermined value A and a predetermined value B for each ink tank 11 as determination information.

  First, in step S01 shown in FIG. 5, the ink tank 11 to be determined by the liquid level lowering determination unit 43 is selected from the ink tanks 11a, 11b, 11c, and 11d. Subsequently, in step S02, the liquid level lowering determination unit 43 determines whether or not the liquid level lowering has been detected for the ink tank 11 selected in step S01 based on the output signals from the electrodes 15 and 16. It is determined whether or not there is ink IK at a predetermined height.

  If it is determined in step S02 that the liquid level reduction determination unit 43 has detected a liquid level reduction (no ink IK at a predetermined height) (step S02: YES), the process proceeds to step S04. On the other hand, when it is determined in step S02 that the liquid level reduction determination unit 43 has not detected the liquid level reduction (the ink IK is at a predetermined height) (step S02: NO), the process proceeds to step S03.

  In step S03, the liquid level lowering determination unit 43 selects the ink tank 11 to be determined next. Then, it is determined whether or not a liquid level drop is detected for the ink tank 11 selected in step S03.

  In step S04, the ink remaining amount determination unit 44 determines whether or not the ink IK of the predetermined value A or more has been consumed after the determination of the liquid level decrease for the ink tank 11 determined to have detected the liquid level decrease in step S02. judge. The ink remaining amount determination unit 44 compares the consumption after post-liquid level determination with the predetermined value A for the ink tank 11 determined to have detected the liquid level decrease in step S02.

  Here, depending on the setting of the interval at which the liquid level lowering determination unit 43 determines the liquid level lowering, the electrode 16 is not immersed in the ink IK before the liquid level lowering determination is performed. There is a possibility that a certain amount of ink IK has been consumed up to the time when it is determined that the liquid level drop has been detected. If the actual consumption amount is larger than the ink consumption amount calculated as the consumption amount after the determination of the liquid level drop, the ink remaining amount determination unit 44 will run out before the ink end is determined. Risk increases.

  In the present embodiment, the ink consumption calculation unit 42 calculates the ink consumption from the state in which each ink tank 11 is filled with the ink IK. A value calculated from the ink consumption when it is finally determined that the ink IK is at a predetermined height before the decrease is determined is used. For this reason, it is possible to reduce the risk that the actual consumption amount is larger than the ink consumption amount calculated as the consumption amount after the liquid level drop determination. Therefore, it is possible to suppress the risk of the occurrence of idle driving before the ink remaining amount determination unit 44 determines that the ink has ended.

  If it is determined in step S04 that the ink remaining amount determination unit 44 has consumed the ink IK of the predetermined value A or more after the determination of the liquid level drop (step S04: YES), the process proceeds to step S05. In step S05, the ink remaining amount determination unit 44 determines that the ink tank 11 determined to have consumed the ink IK of the predetermined value A or more is an ink near end. The control unit 40 reduces the remaining amount of ink IK to the user by lighting the lamp on the operation panel 111 or displaying on the display unit 47 for the ink tank 11 determined by the ink remaining amount determining unit 44 to be the ink near end. A warning is issued to prompt replenishment of ink IK.

  At this time, when the user replenishes ink IK to the ink tank 11 determined to be ink near-end and presses the reset button, reset processing is performed. That is, the ink consumption amount for the ink tank 11 is initialized, the calculated consumption value stored in the latest consumption storage unit 51, and the calculated consumption value stored in the detected consumption storage unit 52. And are cleared. Then, the ink consumption calculated by the ink consumption calculation unit 42 is cumulatively added from the ink consumption 0 and stored in the latest consumption storage 51 and the detected consumption storage 52.

  In this embodiment, when the user presses the reset button, the liquid level decrease determination unit 43 outputs the output signals from the electrodes 15 and 16 before the ink consumption calculation unit 42 initializes the ink consumption. Based on the above, it is determined whether or not the ink IK is at a predetermined height. The reset process is performed when it is determined that the ink IK is present at the predetermined height, and the reset process is not performed when it is determined that there is no ink IK at the predetermined height. This prevents an error from occurring in subsequent determinations when the reset button is accidentally pressed due to a user's erroneous operation or contact.

  On the other hand, when it is determined in step S04 that the ink remaining amount determination unit 44 has not consumed the ink IK of the predetermined value A or more after the determination of the liquid level drop (step S04: NO), the process proceeds to step S03. Next, the ink tank 11 to be determined is selected.

  In the next step S06, the ink remaining amount determination unit 44 determines whether or not the ink tank 11 that has been determined to be ink near-end in step S05 has consumed the ink IK of a predetermined value B or more after the ink near-end determination. In the determination in step S06, as the ink consumption amount, the calculated consumption value stored in the detection consumption amount storage unit 52 for the target ink tank 11 and the consumption amount stored in the latest consumption amount storage unit 51. The consumption after post-level-decision determination which is the difference from the calculated value of the amount is used, and the value of the post-liquid-level decrease determination is compared with the sum of the predetermined value A and the predetermined value B.

  If it is determined in step S06 that the ink remaining amount determination unit 44 has consumed the ink IK of the predetermined value B or more after the ink near-end determination (step S06: YES), the process proceeds to step S07. In step S07, the ink remaining amount determination unit 44 determines that the ink tank 11 is the ink end. The control unit 40 confirms that the ink tank 11 determined that the ink remaining amount determination unit 44 has reached the end of the ink has run out of ink IK to the user by lighting the lamp on the operation panel 111 or displaying on the display unit 47. A warning is issued to prompt the user to refill ink IK, and printing of the printer 110 is stopped.

  At this time, when the user replenishes the ink IK to the ink tank 11 determined to be the ink end and presses the reset button, the above-described reset process is performed.

  On the other hand, if it is determined in step S06 that the ink remaining amount determination unit 44 has not consumed the ink IK of the predetermined value B or more after the ink near-end determination (step S06: NO), the process proceeds to step S03. The ink tank 11 to be determined is selected.

  In the next step S08, it is determined whether or not the determination up to the ink end has been completed for all of the ink tanks 11 provided in the printer 110. If it is determined in step S08 that the determination up to the ink end has been completed for all of the ink tanks 11 (step S08: YES), the process ends.

  On the other hand, if it is determined in step S08 that the determination up to the ink end has not been completed for all of the ink tanks 11 (step S08: NO), the process proceeds to step S03, and the ink tank to be determined next is determined. Select 11 to continue processing.

  When using the printer 110, the user may replenish the ink tank 11 with the ink IK regardless of the ink near end and the ink end determination by the ink remaining amount determination unit 44. For example, even if the user refills the ink tank 11 with the ink IK before the ink remaining amount determination unit 44 determines that the ink near end, if the user presses the reset button, the ink consumption amount for the ink tank 11 is initialized. Then, calculation of the ink consumption by the ink consumption calculation unit 42 starts.

  When the user refills the ink tank 11 with the ink IK, the user may forget to press the reset button. In such a case, the calculation of the ink consumption by the ink consumption calculation unit 42 is continued without being initialized. Further, since the height of the liquid level when the user refills the ink tank 11 with the ink IK is not always constant, the amount of ink IK that can be consumed after the ink IK is replenished until the ink end is determined is May vary.

  That is, the ink consumption amount calculated by the ink consumption amount calculation unit 42 and stored in the latest consumption amount storage unit 51 and the detected consumption amount storage unit 52 is actually stored and consumed in the ink tank 11. Does not necessarily correspond to the amount of However, when the ink remaining amount determination unit 44 determines the ink near end and the ink end, the calculated amount of consumption stored in the detected consumption amount storage unit 52 and the latest consumption amount storage unit 51 are used as the ink consumption amount. Since the difference with the calculated value of consumption stored in is used, the accuracy of determination is not affected.

  Note that the printer 110 according to the present embodiment uses the predetermined value A and the predetermined value B, which are determination information for the ink remaining amount determination unit 44 to determine the ink near end and the ink end for each ink tank 11. It is designed to be able to set different values for each ink tank 11 as appropriate. Accordingly, the predetermined value A and the predetermined value B are set not only for the black ink but also for the color ink, depending on the consumption (usage frequency) of each type of ink IK. Ink near end and ink end can be determined. Thereby, even when the destination and use are different, the capacity of the ink tank 11 is different, and the type of ink IK is different, the basic values can be changed by changing the setting of the predetermined value A and the predetermined value B. The configuration remains the same and can be widely applied.

(Second Embodiment)
In the second embodiment, the configuration of the printer and the scanner in the printer system is substantially the same as that in the first embodiment, and the configuration and arrangement of the pair of conductive members in the ink supply unit are different. Here, a difference between the ink supply unit and the first embodiment will be described. FIG. 6 is a schematic configuration diagram of an ink supply unit according to the second embodiment. Specifically, FIG. 6A is a plan view of the ink supply unit, and FIG. 6B is a cross-sectional view taken along the line AA ′ of FIG. Constituent elements common to the first embodiment are denoted by the same reference numerals and description thereof is omitted.

<Configuration of ink supply unit>
As shown in FIGS. 6A and 6B, the ink supply unit 10A includes four ink tanks 11a, 11b, 11c, and 11d, a holding unit 13, a detection substrate 14, and electrodes as a pair of conductive members. 15A and an electrode 16A. In the ink supply unit 10 </ b> A, the holding unit 13 and the detection substrate 14 are arranged along the Y-axis direction on the side surface on the rear (−X direction) side of the ink tank 11.

  A pair of electrodes 15A and 16A are electrically connected to the detection substrate 14 for each ink tank 11. A total of four pairs of electrodes 15A and 16A corresponding to the four ink tanks 11 are arranged along the extending direction of the detection substrate 14.

  As shown in FIG. 6A, the electrode 15A and the electrode 16A are arranged such that the longitudinal direction is along the depth direction (X-axis direction) of the ink tank 11 from the detection substrate 14 toward the front (+ X direction). Yes. The electrode 15A and the electrode 16A have substantially the same length.

  As shown in FIG. 6B, the electrode 15A and the electrode 16A are provided at a predetermined height from the bottom surface. As in the first embodiment, the predetermined height is appropriately set depending on, for example, the capacity of the ink tanks 11a, 11b, 11c, and 11d, the consumption amount of each ink IK during a predetermined period, and the like.

  As in the first embodiment, in the ink tanks 11b and 11d, the electrode 15A and the electrode 16A are immersed in the inks IKb and IKd, and therefore, the voltage between the electrode 15A and the electrode 16A is applied by the applied voltage. Current flows through As a result, the liquid level lowering determination unit 43 determines that the inks IKb and IKd are at a predetermined height with respect to the ink tanks 11b and 11d.

  On the other hand, in the ink tanks 11a and 11c, since the electrode 15A and the electrode 16A are not immersed in the inks IKa and IKc, no current flows between the electrode 15A and the electrode 16A due to the applied voltage. As a result, the liquid level lowering determination unit 43 determines that the inks IKa and IKc are not at a predetermined height with respect to the ink tanks 11a and 11c.

  As in the first embodiment, since the ink tank 11a and the ink tanks 11b, 11c, and 11d have different capacities, the liquid level when the liquid level lowering determination unit 43 determines that there is no ink IK at a predetermined height. The remaining amount at the time of decrease determination differs between the ink tank 11a and the ink tanks 11b, 11c, and 11d.

  If the ink tank 11a and the ink tanks 11b, 11c, and 11d are to have the same remaining amount at the time of liquid level reduction determination, in the second embodiment, the electrodes 15A and 16A disposed in the ink tank 11a It is necessary to make the height different from that of the ink tanks 11b, 11c, and 11d. Therefore, it is necessary to change the shape of the detection substrate 14 and the holding unit 13 extending in the Y-axis direction to a complicated shape.

  In the second embodiment, the determination of the liquid level decrease by the liquid level decrease determination unit 43 and the determination of the ink near end and the ink end by the ink remaining amount determination unit 44 are performed in the same manner as in the first embodiment. That is, even if the remaining amount at the time of liquid level reduction determination differs between the ink tanks 11, it does not affect the detection accuracy of the remaining amount of ink IK. Therefore, it is not necessary to make the height of the electrodes 15A and 16A arranged in the ink tank 11a different from those of the ink tanks 11b, 11c, and 11d. Therefore, the shapes of the detection substrate 14 and the holding unit 13 are changed to complex shapes. It may not be necessary and can be easily arranged.

  The above-described embodiments merely show one aspect of the present invention, and can be arbitrarily modified and applied within the scope of the present invention. As modifications, for example, the following can be considered.

(Modification 1)
In the above embodiment, in the ink supply units 10 and 10A, the four ink tanks 11 are fixed in the case unit 101, and each ink tank 11 has the injection port 12 for injecting the ink IK from the outside. However, the present invention is not limited to such a form. In the ink supply unit, for example, four ink tanks 11 formed separately are replaceable by the user and are detachably disposed in the case unit 101, and inject the ink IK into each ink tank 11 from the outside. The structure which does not have the injection port 12 may be sufficient.

  In such a configuration in which the ink tank 11 is detachable, the ink tank 11 determined to be the ink end is replaced with a new ink tank 11 filled with the ink IK. When the user installs a new ink tank 11, a reset process is performed. In addition, when the ink tank 11 is detachable, the user can remove and remount the ink tank 11 used halfway, or install the ink tank 11 used halfway by another printer 110. There can be. In these cases, the ink IK in the mounted ink tank 11 is consumed halfway. Even in such a state, the reset process is performed by mounting the ink tank 11. Even in such a case, when the ink near end and the ink end are determined by the ink remaining amount determination unit 44, the calculated value of the consumption amount stored in the detection consumption amount storage unit 52 and the latest consumption are calculated as the ink consumption amount. Since the difference from the calculated consumption value stored in the amount storage unit 51 is used, the accuracy of determination is not affected.

(Modification 2)
In the above-described embodiment, the ink supply units 10 and 10A have the four ink tanks 11 in which the four types of ink IK are individually stored, and the capacity of the ink tank 11 is large and small. The present invention is not limited to such a form. The ink supply unit may have, for example, a configuration having a plurality of ink tanks 11 in which three or less types or five or more types of inks IK are individually accommodated, and the ink tank 11 has three types such as large, medium, and small capacities The configuration described above may be used. Even with such a configuration, the ink near-end by the ink remaining amount determining unit 44 is determined based on the predetermined value A and the predetermined value B set for each ink tank 11 according to the large, medium, small, and type of the ink IK. Since the ink end determination is performed, it is possible to more accurately detect a decrease in the remaining ink amount.

  Even with such a configuration, the printer 110 sets the predetermined value A and the predetermined value B, which are determination information for determining the ink near end and the ink end, to different values for each ink tank 11 as appropriate. Therefore, the ink near end and the ink end can be determined for each ink tank 11 according to the consumption (frequency of use) according to the type of ink IK.

(Modification 3)
In the above embodiment, the printer system 100 that is a multifunction machine including the printer 110 and the scanner 120 as a liquid consuming apparatus has been described as an example. However, the present invention is not limited to such a form. The liquid consuming device may be a single-function printer 110 that does not include the scanner 120.

(Modification 4)
In the above embodiment, an example in which the present invention is applied to a printer and an ink tank has been described, but the present invention is not limited to such a form. The present invention may be used, for example, in a liquid consuming apparatus that ejects or discharges liquid other than ink, and is also applicable to a liquid container that contains such liquid.

(Modification 5)
In the above embodiment, the pair of electrodes 15 and 16 has been described as an example of detecting the presence or absence of the liquid level at the same height from the bottom surface of the ink tank 11 parallel to the plane formed by the XY axes. It is not limited to such a form. The present invention is also applicable to, for example, a case where the bottom surface is inclined with respect to the XY axis plane, or a case where the ink tank is divided into a plurality of rooms. In these cases, the “height from the bottom surface” means that a pair of electrodes having the same shape are arranged from the detection substrate to the plurality of ink tanks, and the liquid level detected by the pair of electrodes is “from the bottom surface”. Corresponds to "height of".

  DESCRIPTION OF SYMBOLS 11, 11a, 11b, 11c, 11d ... Ink tank (liquid container), 12 ... Injection port, 14 ... Detection board | substrate, 15, 15A ... Electrode (a pair of electrically-conductive member), 16, 16A ... Electrode (a pair of electrically-conductive member) 42 ... Ink consumption calculation unit (calculation unit), 43 ... Liquid level drop determination unit (first determination unit), 44 ... Ink remaining amount determination unit (second determination unit), 51 ... Latest consumption amount storage unit (Second storage unit), 52 ... consumption amount storage unit during detection (third storage unit), 53 ... information storage unit for determination (first storage unit), 110 ... printer (liquid consumption device), IK ... Ink (liquid), IKa: black ink (liquid), IKb, IKc, IKd: color ink (liquid).

Claims (10)

A liquid consuming device that individually stores a plurality of different types of liquid in a plurality of liquid containers and consumes the plurality of liquids,
A calculation unit for calculating the consumption of each liquid for each liquid container;
A first storage unit for storing determination information for determining the remaining state of each liquid set for each liquid container;
A pair of conductive members arranged for each liquid container for detecting whether or not each liquid is at a predetermined height from the bottom surface of each liquid container;
A first determination unit that determines whether or not each liquid is at the predetermined height based on output signals from the pair of conductive members for each liquid container;
A second determination unit that determines the remaining state of each liquid for each liquid container,
The capacity of at least two of the plurality of liquid containers is different from each other,
The predetermined height detected by the pair of conductive members is set to the same height for each of the liquid containers,
The second determination unit includes:
After the first determination unit determines that there is no liquid at the predetermined height with respect to any one of the plurality of liquid containers,
Determining the remaining state of the liquid based on the liquid consumption calculated by the calculation unit for the one liquid container and the determination information set for the one liquid container; A liquid consuming device characterized by the above. The liquid consuming device according to claim 1,
The second determination unit includes:
After the first determination unit determines that the liquid is not at the predetermined height with respect to the one liquid container,
The post-determination consumption calculated by the calculation unit as the liquid consumption consumed after the determination for the one liquid container, and the determination information set for the one liquid container; A liquid consuming apparatus that determines the remaining state of the liquid based on the above. The liquid consuming device according to claim 2,
A second storage unit that updates and stores the consumption amount of each liquid calculated for each liquid container by the calculation unit to the latest value;
When the first determination unit determines that the liquid is present at the predetermined height for each liquid container, the consumption amount of each liquid calculated by the calculation unit is updated to the latest value each time and stored. A third storage unit,
The post-determination consumption amount is the value of the consumption amount stored in the second storage unit and before the first determination unit determines that the liquid is not at the predetermined height for each liquid container. Finally, the liquid consumption device is a difference between the consumption value stored in the third storage unit. The liquid consuming device according to any one of claims 1 to 3,
The determination information includes a predetermined value that is set for each liquid container as the amount of the liquid that can be consumed after the first determination unit determines that the liquid is not at the predetermined height.
Of the two liquid containers having different capacities, the predetermined value set for the liquid container having a larger capacity is larger than the predetermined value set for the liquid container having a smaller capacity. A liquid consuming apparatus characterized by the above. The liquid consuming device according to claim 4,
The plurality of liquids include black ink and color ink,
The liquid consuming apparatus, wherein the black ink is stored in the liquid container having the larger capacity, and the color ink is stored in the liquid container having the smaller capacity. The liquid consuming device according to claim 4 or 5,
The determination information includes a first predetermined value and a second predetermined value as the predetermined value,
As the determination of the remaining state of the liquid, the second determination unit determines that the liquid is not at the predetermined height with respect to the one liquid container.
Determining an ink near end to warn of a decrease in the remaining amount of the liquid when the post-determination consumption in the one liquid container is equal to or greater than the first predetermined value;
And determining an ink end for warning that the liquid has run out when the post-determination consumption in the one liquid container is equal to or greater than the second predetermined value,
The liquid consumption apparatus according to claim 1, wherein the second predetermined value is set for each liquid container as a value corresponding to a consumption amount of each liquid consumed in a predetermined period. The liquid consuming device according to any one of claims 1 to 6,
The pair of conductive members arranged for each liquid container is electrically connected, and includes a detection substrate for detecting an energization state between the pair of conductive members in each liquid container,
The heights of the liquid containers are the same, and the liquid containers having different capacities are different in at least one of width and depth,
The detection substrate is disposed above each liquid container,
The pair of conductive members have a longitudinal direction, and are arranged so that the longitudinal direction is along the height direction of each liquid container downward from the detection substrate. The liquid consuming device according to any one of claims 1 to 6,
The pair of conductive members arranged for each liquid container is electrically connected, and includes a detection substrate for detecting an energization state between the pair of conductive members in each liquid container,
The heights of the liquid containers are the same, and the liquid containers having different capacities are different in at least one of width and depth,
The detection substrate is disposed on a side of each liquid container,
The pair of conductive members have a longitudinal direction, and are arranged such that the longitudinal direction extends along the depth direction of each liquid container from the detection substrate toward the side. The liquid consuming device according to any one of claims 1 to 8,
The plurality of liquid containers are fixed to the liquid consumption device,
Each liquid container is provided with an inlet through which the liquid can be injected into the liquid container from the outside. The liquid consuming device according to any one of claims 1 to 8,
The plurality of liquid containers are detachably held from the liquid consumption device,
The liquid consuming device, wherein the pair of conductive members are attached to the liquid containers.

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