Patent Publication Number: US-2023142116-A1

Title: Liquid ejection apparatus and delivery system for liquid ejection head

Description:
This application is a continuation application of U.S. patent application Ser. No. 17/316,395, filed May 10, 2021, which claims the benefit of and priority to Japanese Patent Application No. 2020-087261, filed May 19, 2020, and JP Application Serial Number 2020-083974, filed May 12, 2020. The entire disclosures of the above-mentioned applications are hereby incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a liquid ejection apparatus that ejects a liquid onto a medium and a delivery system for a liquid ejection head. 
     2. Related Art 
     An image forming apparatus as an example of a liquid ejection apparatus described in JP-A-2016-224155 includes a replacement time prediction section that predicts a replacement time of a cartridge as an example of a consumable liquid storage body. The replacement time prediction section periodically predicts the replacement time of the cartridge at which a residual amount of a coloring material is equal to or less than a replacement threshold value from the time of ordering a replacement cartridge based on the residual amount of the coloring material and the consumption tendency. The image forming apparatus includes a replacement ordering section that causes the replacement time prediction section to predict the replacement time of the cartridge, and orders a replacement cartridge automatically or by receiving a request from a user when a period up to the predicted replacement time is equal to or less than an ordering threshold value. Consequently, it is possible to prevent the coloring material of the cartridge from being used up before the replacement cartridge is supplied. That is, the liquid ejection apparatus that reduces concern that downtime may occur due to the absence of a replacement cartridge at the user&#39;s hand is disclosed. 
     The liquid ejection apparatus performs recording on a surface of a medium by ejecting a liquid supplied from a liquid storage body to the liquid ejection head included in the liquid ejection apparatus, from a nozzle of the liquid ejection head toward the surface of the medium. Thus, in the liquid ejection apparatus, there is a case where recording cannot be normally performed on the medium by the liquid ejection apparatus not only when the liquid in the liquid storage body is used up before the supply of a replacement liquid storage body but also when a problem related to ejection in the liquid ejection head occurs. 
     However, in the liquid ejection apparatus described in JP-A-2016-224155, no consideration is given to the occurrence of a problem related to ejection in the liquid ejection head. Thus, when a problem related to the ejection in the liquid ejection head occurs and the liquid ejection apparatus cannot normally perform recording on the medium, downtime occurs in the liquid ejection apparatus due to the absence of a new replacement liquid ejection head at the user&#39;s hand. 
     SUMMARY 
     According to an aspect of the present disclosure, there is provided a liquid ejection apparatus including a liquid ejection head that is detachably attached and ejects a liquid; and a control section that is configured to transmit a delivery request for a new liquid ejection head to a server apparatus via a network. 
     According to another aspect of the present disclosure, there is provided a delivery system for a liquid ejection head including the liquid ejection apparatus, and the server apparatus including a reception section that receives the delivery request for the new liquid ejection head transmitted from the control section. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view illustrating a liquid ejection apparatus according to first and second embodiments. 
         FIG.  2    is a perspective view illustrating a state in which a casing is detached in the liquid ejection apparatus. 
         FIG.  3    is a side sectional view illustrating a periphery of a carriage unit broken along the line III-III in  FIG.  2   . 
         FIG.  4    is a schematic view illustrating a liquid flow path from a liquid storage body to a flow path in a head. 
         FIG.  5    is a flowchart illustrating a liquid discharge process executed by a control section. 
         FIG.  6    is a flowchart illustrating a liquid resupply process executed by the control section. 
         FIG.  7    is a flowchart illustrating a maintenance process executed by the control section. 
         FIG.  8    is a block diagram illustrating a delivery system for a liquid ejection head. 
         FIG.  9    is a flowchart illustrating an ejection-related problem determination process. 
         FIG.  10    is a flowchart illustrating a check flow according to the first embodiment. 
         FIG.  11    is a flowchart illustrating a new liquid ejection head attachment check process. 
         FIG.  12    is a flowchart illustrating a check flow according to the second embodiment. 
         FIG.  13    is a schematic view illustrating a delivery system according to a third embodiment. 
         FIG.  14    is a schematic sectional view of a liquid storage body and a refill container. 
         FIG.  15    is a perspective view of a plurality of liquid storage bodies. 
         FIG.  16    is a perspective view of a pour cover. 
         FIG.  17    is a sectional view of the pour cover and a holding portion. 
         FIG.  18    is a flowchart illustrating a refill routine. 
         FIG.  19    is a flowchart illustrating the refill routine. 
         FIG.  20    is a schematic view of a display section displaying a refill prompting screen. 
         FIG.  21    is a schematic view of a display section that displays a sending check screen. 
         FIG.  22    is a schematic view of a display section displaying a continuation selection screen. 
         FIG.  23    is a schematic diagram illustrating a delivery system according to a fourth embodiment. 
         FIG.  24    is a flowchart illustrating a replacement routine. 
         FIG.  25    is a flowchart illustrating the replacement routine. 
         FIG.  26    is a schematic view of a display section displaying a replacement prompting screen. 
         FIG.  27    is a schematic view of a display section that displays a sending check screen. 
         FIG.  28    is a schematic view of a display section displaying a continuation selection screen. 
         FIG.  29    is a flowchart illustrating a refill routine related to a modified example. 
         FIG.  30    is a flowchart illustrating a replacement routine related to a modified example. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     In the drawings, a direction of gravity is indicated by a Z axis when a liquid ejection apparatus is placed on a horizontal plane, and directions along a plane intersecting the Z axis are indicated by an X axis and a Y axis. The X axis, Y axis, and Z axis are preferably orthogonal to each other, and the X axis and Y axis are along the horizontal plane. In the following description, the X axis direction will also be referred to as a width direction X, the Y axis direction will also be referred to as a depth direction Y, a transport direction of a medium during recording will also be referred to as a transport direction Y1, and the Z axis direction will also be referred to as a vertical direction Z. In the present embodiment, since the width direction X is also a scanning direction of a carriage described later, the width direction X will also be referred to as a scanning direction X. A surface on which the operation panel described later is disposed in the Y axis will be referred to as a front surface, and a surface opposite to the front surface will be referred to as a rear surface. 
     First Embodiment 
     Configuration of Liquid Ejection Apparatus 
     As illustrated in  FIG.  1   , a liquid ejection apparatus  11  includes a rectangular parallelepiped casing  12  and an upper cover  13  provided on the +Z direction side of the casing  12  so as to be openable and closable with, for example, the rear surface side as a rotation axis. The liquid ejection apparatus  11  is a multi-function peripheral as an example, and includes a recording unit  20  that occupies most of the casing  12 , and a reading unit  30  formed of an end portion of the casing  12  on the +Z direction side and the upper cover  13 . The liquid ejection apparatus  11  includes a control section  70  that controls the recording unit  20  and the reading unit  30 . The control section  70  is configured with, for example, a computer, a processing circuit including a memory, and the like, and controls the recording unit  20  and the reading unit  30  according to a program stored in the memory. 
     A cassette  21  as an example of a medium storage portion is inserted into and detached from a recess  14  provided in a lower front portion of the casing  12 . A plurality of media M are stored in the cassette  21 . An operated portion  21   a  that is attachable and detachable by a user by hooking a finger is provided at the center of the front surface of each cassette  21 . 
     A discharge port  15  from which the recorded medium M is discharged is open at a position on the +Z direction side of the cassette  21  in the casing  12 . An extendable discharge tray  22  is provided between the discharge port  15  and the cassette  21 . The discharge tray  22  is used in a state of extending downstream in the transport direction Y1, and the discharged medium M after recording is loaded on the discharge tray  22 . An operation panel  24  is provided on the entire surface of the casing  12  at a position on the +Z direction side of the discharge port  15 . 
     The operation panel  24  includes an operation section  25  including a plurality of switches operated when a user gives an instruction to the liquid ejection apparatus  11 , and a display section  26  displaying a menu, a message, or the like. The operation section  25  includes a power switch  25   a , a selection switch, and the like. Here, the display section  26  may be a touch panel, and an operation function of the display section  26  may also serve as a part of the operation section  25 . The control section  70  controls the liquid ejection apparatus  11  based on an operation performed by the user by using the operation section  25 . The control section  70  displays a menu, a message, or the like on the display section  26  as necessary. 
     As illustrated in  FIG.  1   , the upper cover  13  is a platen cover  31  of the reading unit  30  in the present embodiment, and an is provided thereon with an automatic document feeder  32  having a document tray  33  on which a plurality of original documents D are placeable. The reading unit  30  has a sheet feeder type scanner function of feeding and reading the original documents D positioned in the depth direction Y by edge guides  33   a  one by one from the document tray  33 , and a flatbed type scanner function of reading the original documents D placed on a platen that is exposed when the platen cover  31  is opened. In the sheet feeder type scanner function, the original documents D fed one by one from the document tray  33  are read by the reading unit  30  and then discharged to the discharge tray  31   a.    
     In addition to the ink jet type recording function, the liquid ejection apparatus  11  which is a multi-function peripheral provided with the reading unit  30  has a scanner function in which the reading unit  30  reads the original document D and a copy recording function in which an image of the original document D read by the reading unit  30  is recorded. 
     As illustrated in  FIG.  1   , a liquid supply unit  27  is provided at one end on the front surface of the casing  12  on the +X direction side. A plurality of liquid storage bodies  28  each storing a liquid such as ink are accommodated in the liquid supply unit  27 . The plurality of liquid storage bodies  28  are ink cartridges that store inks with different colors such as black, cyan, magenta, and yellow. The liquid stored in the liquid storage body  28  is used for the liquid ejection apparatus  11  to eject the liquid onto a medium M and to perform recording. The liquid supply unit  27  has a plurality of window portions  27   a  indicating an amount of the liquid in each liquid storage body  28  on the front surface. 
     The liquid supply unit  27  has a lid portion  27   b  that can be opened and closed upward. For example, the liquid ejection apparatus  11  has a configuration in which, when the user looks at the window portions  27   a  and liquid amounts decrease, the user opens the lid portion  27   b  to replace the liquid storage bodies  28 . 
     As illustrated in  FIG.  2   , the liquid ejection apparatus  11  has a transport region TA in which the medium M supplied from the cassette  21  is transported at the center thereof in the width direction X. The liquid ejection apparatus  11  includes a transport section  40  that feeds the media M that is a recording target one by one from the cassette  21  into the recording unit  20  included in the liquid ejection apparatus  11  and transports the media M along a path passing through the transport region TA, and a carriage unit  50  that ejects a liquid to perform recording while moving with respect to the medium M in the transport region TA. 
     The transport section  40  has a feed portion  41  that feeds media M one by one from the cassette  21  at the rear of the liquid ejection apparatus  11 . The feed portion  41  has a plurality of intermediate rollers (not illustrated) arranged side by side in the transport direction Y1. The feed portion  41  reverses the medium M fed rearward from the cassette  21  due to rotation of a pickup roller (not illustrated) along outer circumferences of the intermediate rollers, and then transports the medium M through the transport region TA in the transport direction Y1. A support portion  42  that supports the medium M on which recording is performed by the carriage unit  50  is disposed in the transport region TA. The transport section  40  has a plurality of rollers (not illustrated) along the transport path, and transports the medium M in the transport direction Y1 due to rotation of the rollers. The transport section  40  is controlled by the control section  70  illustrated in  FIG.  1   . 
     As illustrated in  FIG.  2   , the carriage unit  50  includes a carriage  51  and a liquid ejection head  54  mounted on the carriage  51  and ejecting a liquid onto the medium M as illustrated in  FIG.  3   . The liquid ejection apparatus  11  is configured such that the liquid ejection head  54  ejects the liquid stored in the liquid storage body  28 . A carriage motor  52 , which is a drive source of the carriage unit  50 , is disposed behind one end of a movement path of the carriage unit  50  in the liquid ejection apparatus  11 . A drive force of the carriage motor  52  is transmitted to the carriage unit  50  via an endless timing belt  53 . The timing belt  53  is wound around a pair of pulleys (not illustrated) and stretched along a first guide member  17  to extend in the scanning direction X. One pulley is connected to an output shaft of the carriage motor  52 . The carriage unit  50  and the carriage motor  52  are controlled by the control section  70  illustrated in  FIG.  1   . 
     As illustrated in  FIG.  3   , the carriage unit  50  having the liquid ejection head  54  on a surface thereof on the −Z direction side is guided by each of the first guide member  17  and a second guide member  18 , and is thus supported to be reciprocally movable in the scanning direction X intersecting the transport direction Y1 of the medium M. That is, when the carriage motor  52  is driven in forward and reverse directions, the carriage unit  50  having the liquid ejection head  54  is reciprocally moved in the scanning direction X along the first guide member  17  and the second guide member  18  arranged in the vertical direction Z. 
     As illustrated in  FIG.  3   , a support portion  42  that supports the medium M is disposed at a position on the −Z direction side facing the movement region of the liquid ejection head  54 . An appropriate gap is secured between the medium M supported by the support portion  42  and the liquid ejection head  54 . In the process of the carriage unit  50  reciprocally moving in the scanning direction X along the first guide member  17  and the second guide member  18 , the liquid is ejected toward the medium M from a nozzle (not illustrated) of the liquid ejection head  54 . As a result, an image or the like is printed on the medium M. 
     The control section  70  illustrated in  FIG.  1    controls the liquid ejection head  54  for ejecting the liquid onto the medium M. In order for the control section  70  to control the liquid ejection head  54 , the control section  70  and the liquid ejection head  54  are coupled to each other via a flexible flat cable (not illustrated). 
     In  FIG.  2   , the carriage unit  50  is located at the home position HP to stand by during non-recording in which recording is not performed on the medium M. As illustrated in  FIG.  2   , in the present embodiment, a position where the carriage unit  50  is located at the end opposite to the disposition position of the liquid supply unit  27  in the scanning direction X is the home position HP. A position of the end opposite to the home position HP in the scanning direction X is an anti-home position AH of the carriage  51 . When recording is performed on the medium M, the carriage  51  is reciprocally moved in a recording region corresponding to a length of the medium M in the scanning direction X within a movable range between the home position HP and the anti-home position AH. 
     As illustrated in  FIG.  2   , the above-described liquid storage body  28  mounted on the liquid ejection apparatus  11  can store a liquid supplied to the liquid ejection head  54  illustrated in  FIG.  3    in the liquid supply unit  27 , and is provided at a position separated from the carriage  51 . In the present embodiment, the liquid storage body  28  that supplies the liquid to the carriage unit  50  is disposed at an installation position on the anti-home position AH side opposite to the home position HP of the carriage unit  50 . 
     When the user opens the upper cover  13  illustrated in  FIG.  1   , the carriage unit  50  illustrated in  FIG.  2    is exposed. More specifically, when the carriage unit  50  is located at the home position HP illustrated in  FIG.  2    to stand by during non-recording in which recording is not performed on the medium M, the user can access the liquid ejection head  54  illustrated in  FIG.  3    mounted on the carriage unit  50  by opening the upper cover  13 . Consequently, the user can perform work of detaching the liquid ejection head  54  from the carriage unit  50  and attaching a new liquid ejection head thereto. 
     As illustrated in  FIG.  2   , the liquid ejection apparatus  11  includes a maintenance section  71  that performs cleaning or the like as maintenance of the liquid ejection head  54  at a position directly under the carriage unit  50  that has moved to a position deviated from the transport region TA in which the support portion  42  is disposed in the −X direction. The liquid ejection apparatus  11  includes a gap adjustment mechanism  72  that changes a height position of the liquid ejection head  54  with respect to the support portion  42  to adjust a gap between the liquid ejection head  54  and the medium M according to the type of the medium M. The maintenance section  71  and the gap adjustment mechanism  72  are controlled by the control section  70  illustrated in  FIG.  1   . 
     Configuration of Maintenance Section 
     As illustrated in  FIG.  4   , the liquid ejection head  54  includes a nozzle surface  54   b  having a plurality of nozzles  54   a  ejecting liquids L. As described above, the liquid ejection apparatus  11  includes the maintenance section  71  that performs cleaning or the like of the nozzles  54   a  as maintenance of the liquid ejection head  54  at the position directly under the carriage unit  50  that has moved to the position deviated from the transport region TA in which the support portion  42  is disposed in the −X direction. The maintenance section  71  includes a wiper unit (not illustrated), a flushing unit (not illustrated), and a cap unit (not illustrated). In the present embodiment, the cap unit, the wiper unit, and the flushing unit are located along with the support portion  42  illustrated in  FIG.  3    in the scanning direction X at a position in the depth direction Y facing the nozzle surface  54   b  of the liquid ejection head  54 . An order in which these three units are arranged is not limited. 
     As illustrated in  FIG.  4   , the cap unit has a cap portion  73 . The nozzle surface  54   b  of the liquid ejection head  54  faces the cap portion  73  when the carriage unit  50  is further located at the home position HP illustrated in  FIG.  2    at the position deviated from the transport region TA in the −X direction. The cap portion  73  is moved between a contact position illustrated in  FIG.  4    in contact with the liquid ejection head  54  at the home position HP and a retreat position away from the liquid ejection head  54  in the −Z direction. The cap portion  73  located at the contact position comes into contact with the liquid ejection head  54  so as to surround the nozzles  54   a  and forms a closed space CS surrounding the nozzles  54   a . That is, the cap portion  73  caps the liquid ejection head  54 . The closed space CS formed through the capping suppresses drying of the liquid L in the nozzles  54   a.    
     The cap portion  73  is coupled to a suction pump  73   b  via a discharge flow path  73   a . When the suction pump  73   b  is driven in a state in which the cap portion  73  caps the liquid ejection head  54 , a negative pressure is generated in the cap portion  73 . The thickened liquid L, air bubbles, and the like are discharged from the nozzles  54   a  due to the action of the negative pressure generated in the cap portion  73 . The liquid L being forced to be discharged from the nozzles  54   a  through suction in this way is also referred to as suction cleaning. 
     The wiper unit (not illustrated) has a wiping member configured to remove the liquid L adhering to the nozzle surface  54   b . The wiper unit wipes the nozzle surface  54   b  of the liquid ejection head  54  with the wiping member. The term “wiping” is an operation of wiping the nozzle surface  54   b  in order to remove the liquid L or dirt such as dust adhering to the nozzle surface  54   b  of the liquid ejection head  54 . 
     The flushing unit (not illustrated) has a liquid storing portion (not illustrated) that stores the liquid L ejected by the liquid ejection head  54 . The term “flushing” is an operation of ejecting the liquid L from the nozzles  54   a  regardless of a recording process for the purpose of preventing and eliminating clogging of the nozzles  54   a  of the liquid ejection head  54 . 
     Configuration of Liquid Flow Path of Liquid Ejection Head 
     As illustrated in  FIG.  4   , the liquid ejection head  54  includes a first in-head flow path  54   d  communicating a supply coupling portion  54   c  with the plurality of nozzles  54   a . The liquid ejection apparatus  11  includes a first liquid supply flow path  75  as an example of a supply flow path along which the liquid L from the liquid storage body  28  is supplied to the liquid ejection head  54 . In the present embodiment, the first liquid supply flow path  75  includes a portion composed of a flexible tube. An upstream end (not illustrated) of the first liquid supply flow path  75  is coupled to the liquid storage body  28 . 
     In the present embodiment, a flow direction F of the liquid L refers to a passing direction of the liquid L from the liquid storage body  28  to the liquid ejection head  54 . A downstream refers to the flow direction F side from a reference position, and an upstream refers to a side opposite to the flow direction F from the reference position. 
     A downstream end  75   a  of the first liquid supply flow path  75  is attachably and detachably coupled to the supply coupling portion  54   c  of the liquid ejection head  54 . The downstream end  75   a  may be an end of a flexible tube, and may be a joint that can be easily attached to and detached from the supply coupling portion  54   c.    
     The liquid ejection apparatus  11  includes a first opening/closing valve  75   b  as an example of an opening/closing mechanism capable of opening and closing the first liquid supply flow path  75 . That is, the first opening/closing valve  75   b  as an example of an opening/closing mechanism opens and closes the first liquid supply flow path  75  as an example of a supply flow path. The first opening/closing valve  75   b  may be coupled to the liquid ejection head  54  side by a half or more of a total length of the first liquid supply flow path  75  from the viewpoint of reducing a volume of the first liquid supply flow path  75  from the first opening/closing valve  75   b  to the liquid ejection head  54 , and may more preferably be coupled to the vicinity of the downstream end  75   a . When the first opening/closing valve  75   b  is opened, the liquid ejection head  54  and the liquid storage body  28  are communicated with each other. When the first opening/closing valve  75   b  is closed, the liquid ejection head  54  and the liquid storage body  28  are shut off. 
     The liquid ejection apparatus  11  includes a first atmosphere communication path  76  capable of communicating the first liquid supply flow path  75  with the atmosphere. The first atmosphere communication path  76  is coupled to the downstream of the first opening/closing valve  75   b  in the first liquid supply flow path  75 . 
     The liquid ejection apparatus  11  includes a first atmosphere opening valve  76   a  capable of opening and closing the first atmosphere communication path  76 . The first atmosphere opening valve  76   a  is coupled to the first atmosphere communication path  76 . When the first atmosphere opening valve  76   a  is opened, the first liquid supply flow path  75  is communicated with the atmosphere. When the first atmosphere opening valve  76   a  is closed, the first liquid supply flow path  75  is shut off from the atmosphere. 
     In the present embodiment, as described above, the liquid supply unit  27  accommodates the plurality of liquid storage bodies  28  each storing the liquid L such as ink. The plurality of liquid storage bodies  28  store inks with different colors such as black, cyan, magenta, and yellow. That is, in the present embodiment, since there are four types of liquids L used for recording, the liquid ejection head  54  has the first in-head flow path  54   d , a second in-head flow path (not illustrated), a third in-head flow path (not illustrated), and a fourth in-head flow path (not illustrated) as four in-head flow paths for the four types of liquids L. 
     The liquid ejection head  54  has the first liquid supply flow path  75 , a second liquid supply flow path (not illustrated), a third liquid supply flow path (not illustrated), and a fourth liquid supply flow path (not illustrated) as supply flow paths for the respective in-head flow paths. The liquid ejection head  54  has the first opening/closing valve  75   b , a second opening/closing valve (not illustrated), a third opening/closing valve (not illustrated), and a fourth opening/closing valve (not illustrated) as opening/closing valves capable of opening and closing the supply flow paths for the respective in-head flow paths. The liquid ejection head  54  has the first atmosphere communication path  76 , a second atmosphere communication path (not illustrated), a third atmosphere communication path (not illustrated), and a fourth atmosphere communication path (not illustrated) as atmosphere communication paths for the respective in-head flow paths. The liquid ejection head  54  has the first atmosphere opening valve  76   a , a second atmosphere opening valve (not illustrated), a third atmosphere opening valve (not illustrated), and a fourth atmosphere opening valve (not illustrated) as atmosphere opening valves capable of opening and closing the atmosphere communication paths for the respective in-head flow paths. 
     In the present embodiment, since the flow paths of the four types of liquids from the liquid storage bodies  28  to the in-head flow paths of the liquid ejection head  54  have the same configuration, a flow path of one type of liquid L will be described. Therefore, the description of the flow paths of the other liquids L will be omitted. 
     Liquid Ejection Head Replacement Flow 
     In the present embodiment, the liquid ejection head  54  that ejects the liquid L is detachably attached by a user. That is, the liquid ejection apparatus  11  has a configuration in which the liquid ejection head  54  can be replaced by the user. The liquid ejection head replacement flow includes an operation of removing a liquid in the liquid ejection head  54  illustrated in  FIG.  5   , a step of checking whether or not the liquid ejection head  54  has been replaced, an operation of filling the liquid ejection head  54  with a liquid illustrated in  FIG.  6   , and a maintenance step of the liquid ejection head  54  illustrated in  FIG.  7   . 
     The control section  70  may display a replacement procedure of the liquid ejection head  54  on the display section  26  as one of the liquid ejection head replacement flows. That is, the control section  70  may be able to perform the liquid ejection head replacement flow that is a flow for attaching a new liquid ejection head  54  requested and delivered according to a delivery flow described later. In the present embodiment, the operation of removing a liquid in the liquid ejection head  54  and the operation of filling the new liquid ejection head  54  with a liquid are automatically performed by the control section  70 . Thus, the control section  70  may display a progress status of the liquid ejection head replacement flow on the display section  26 , and may also display a message for prompting the user to perform replacement with the new liquid ejection head on the display section  26  at a timing at which the operation of removing a liquid in the liquid ejection head  54  is completed. When the liquid ejection apparatus  11  does not include the display section  26 , or when a display area of the display section  26  is small, the user may use an application program or the like in a PC or a mobile terminal to display a progress status of the liquid ejection head replacement procedure or the liquid ejection head replacement flow on a screen of the PC or the mobile terminal. 
     First, with reference to a flowchart of  FIG.  5   , a description will be made of an example of the operation of removing a liquid in the liquid ejection head  54 , performed by the control section  70  before the user replaces the liquid ejection head  54 . 
     As illustrated in  FIG.  5   , the control section  70  controls the constituents of the liquid ejection apparatus  11  to perform the operation of removing a liquid in the liquid ejection head  54  by executing a discharge process described below. It is assumed that the first atmosphere opening valve  76   a  is opened at the start of the liquid removal operation. 
     When the operation of removing a liquid in the liquid ejection head  54  is performed, the carriage unit  50  is located at the home position HP illustrated in  FIG.  2   . That is, the nozzle surface  54   b  of the liquid ejection head  54  faces the cap portion  73 . 
     In step S 101 , the control section  70  controls the movement mechanism of the cap unit to move the cap portion  73  from the retreat position to the contact position illustrated in  FIG.  4   . When the cap portion  73  is located at the contact position, the cap portion  73  comes into contact with the liquid ejection head  54 . Consequently, the closed space CS is formed in the portion where the plurality of nozzles  54   a  are opened. When the cap portion  73  is located at the contact position at the start of the liquid removal operation, step S 101  may be skipped. 
     In step S 102 , the control section  70  closes the first opening/closing valve  75   b  and the first atmosphere opening valve  76   a . That is, step S 102  is a step in which the first opening/closing valve  75   b  as an example of an opening/closing mechanism closes the first liquid supply flow path  75  as an example of a supply flow path, and the first atmosphere opening valve  76   a  closes the first atmosphere communication path  76 . 
     In step S 103 , the control section  70  drives the suction pump  73   b . Consequently, the suction pump  73   b  sucks the liquid L in the closed space CS and discharges the liquid L to a waste liquid storage portion (not illustrated). The control section  70  stands by while driving the suction pump  73   b  until a first specified time, which is an example of a predetermined time, elapses. When the first specified time elapses, the control section  70  proceeds to a process in step S 104 . The first specified time mentioned here is, for example, the time required for the pressure in the closed space CS to drop from −50 kPa to −95 kPa by driving the suction pump  73   b.    
     In step S 104 , the control section  70  opens the first atmosphere opening valve  76   a . In step S 104 , the control section  70  stands by while driving the suction pump  73   b  until the specified time elapses after the first atmosphere opening valve  76   a  is opened. That is, the liquid ejection apparatus  11  continues suction with the suction pump  73   b  even after the first atmosphere opening valve  76   a  is opened. When the specified time has elapsed, the control section  70  proceeds to step S 105 . The specified time mentioned here is, for example, the time required to discharge the liquid L from the first opening/closing valve  75   b  to the nozzles  54   a . Driving of the suction pump  73   b  may be stopped at the same time as opening the first atmosphere opening valve  76   a , or may be stopped before opening the first atmosphere opening valve  76   a.    
     In step S 105 , the control section  70  stops the suction pump  73   b . The processes in steps S 101  to S 105  correspond to a discharge operation of discharging the liquid L in the liquid ejection head  54 . 
     In step S 106 , the control section  70  closes the first atmosphere opening valve  76   a . That is, the liquid ejection apparatus  11  closes the first atmosphere opening valve  76   a  after the discharge operation is finished. 
     In step S 107 , the control section  70  controls the movement mechanism of the cap unit such that the cap portion  73  is moved from the contact position illustrated in  FIG.  4    to the retreat position. Consequently, the liquid removal operation is finished. 
     As described above, the liquid ejection apparatus  11  performs suction for a predetermined time with the suction pump  73   b  in a state in which the first opening/closing valve  75   b  and the first atmosphere opening valve  76   a  are closed, and then opens the first atmosphere opening valve  76   a , prior to detaching the liquid ejection head  54  from the downstream end  75   a  of the first liquid supply flow path  75 . Consequently, the liquid ejection apparatus  11  executes the discharge operation of discharging the liquid L in the liquid ejection head  54 . As a result, the liquid L in the liquid ejection head  54  is hardly left, and thus the user can detach the liquid ejection head  54  from the liquid ejection apparatus  11 . 
     In the present embodiment, the closing operation for the first opening/closing valve  75   b  and the opening/closing operation for the first atmosphere opening valve  76   a  are automatically performed by the control section  70 , but may be manually performed by the user. In this case, it is desirable that the control section  70  displays a step of the liquid removal operation on the display section  26 , and performs display for prompting a closing operation for the first opening/closing valve  75   b  and an opening operation and a closing operation for the first atmosphere opening valve  76   a  on the display section  26  at the time of a step in which an opening/closing operation for each valve is required. 
     The routine illustrated in  FIG.  5    is a routine related to a discharge operation in which the liquid ejection apparatus  11  discharges one type of liquid from the liquid ejection head  54 . In the present embodiment, as described above, the liquid supply unit  27  included in the liquid ejection apparatus  11  stores a plurality of liquid storage bodies  28  respectively storing a plurality of types of liquids L. The liquids L stored in the plurality of liquid storage bodies  28  are respectively supplied to the in-head flow paths of the liquid ejection head  54 . Thus, the liquid ejection apparatus  11  similarly executes the discharge operation of discharging all the liquids L supplied to the liquid ejection head  54 . As a result, all the liquids L in the liquid ejection head  54  are hardly left, and thus the user can detach the used liquid ejection head  54  from the carriage unit  50  included in the liquid ejection apparatus  11 . The user can attach a new unused liquid ejection head  54  to the carriage unit  50  included in the liquid ejection apparatus  11 . 
     Next, with reference to a flowchart of  FIG.  6   , a description will be made of an example of an operation of filling the new liquid ejection head  54  with a liquid, performed by the control section  70  after the user replaces the liquid ejection head  54 . 
     As illustrated in  FIG.  6   , the control section  70  controls the constituents of the liquid ejection apparatus  11  to perform the operation of filling the liquid ejection head  54  with a liquid by executing a resupply process. 
     In step S 201 , the control section  70  controls the movement mechanism of the cap unit such that the cap portion  73  is moved from the retreat position to the contact position illustrated in  FIG.  4   . When the cap portion  73  is located at the contact position, the cap portion  73  comes into contact with the liquid ejection head  54 . Consequently, the closed space CS in which the openings of the plurality of nozzles  54   a  are communicated with each other is formed. 
     In step S 202 , the control section  70  closes the first opening/closing valve  75   b  and the first atmosphere opening valve  76   a . When the liquid filling operation is performed following the liquid removal operation for the liquid ejection head  54 , this step is unnecessary because the first opening/closing valve  75   b  and the first atmosphere opening valve  76   a  are already closed. 
     In step S 203 , the control section  70  drives the suction pump  73   b . Consequently, the suction pump  73   b  sucks the liquid L in the closed space CS and discharges the liquid L to a waste liquid storage portion (not illustrated). The control section  70  stands by while driving the suction pump  73   b  until a second specified time elapses. When the second specified time elapses, the control section  70  proceeds to a process in step S 204 . Here, the second specified time is, for example, the time required for the pressure in the closed space CS to drop from −50 kPa to −95 kPa by driving the suction pump  73   b.    
     In step S 204 , the control section  70  opens the first opening/closing valve  75   b . In step S 204 , the control section  70  stands by while driving the suction pump  73   b  until the specified time elapses after the first opening/closing valve  75   b  is opened. That is, the liquid ejection apparatus  11  continues suction by the suction pump  73   b  even after the first opening/closing valve  75   b  is opened. When the specified time has elapsed, the control section  70  proceeds to step S 205 . The specified time mentioned here is, for example, the time required to perform filling with the liquid L from the first opening/closing valve  75   b  to the nozzles  54   a . Driving of the suction pump  73   b  may be stopped at the same time as opening the first opening/closing valve  75   b , or may be stopped before opening the first opening/closing valve  75   b.    
     In step S 205 , the control section  70  stops the suction pump  73   b . The processes in steps S 201  to S 205  correspond to the resupply operation of supplying the liquid L to the liquid ejection head  54 . Consequently, the liquid filling operation is finished. 
     As described above, in the liquid ejection apparatus  11  closes the first opening/closing valve  75   b  and the first atmosphere opening valve  76   a  after the user detaches the liquid ejection head  54  and couples the new liquid ejection head  54  to the downstream end  75   a  of the first liquid supply flow path  75 . In this state, the liquid ejection apparatus  11  sucks the liquid with the suction pump  73   b  for a predetermined time, and then opens the first opening/closing valve  75   b . Consequently, the liquid ejection apparatus  11  executes the resupply operation of supplying the liquid L into the liquid ejection head  54 . 
     In the present embodiment, the opening/closing operation for the first opening/closing valve  75   b  and the closing operation for the first atmosphere opening valve  76   a  are automatically performed by the control section  70 , but may be manually performed by the user. In this case, it is desirable that the control section  70  displays a step of the liquid filling operation on the display section  26 , and performs display for prompting an opening operation and a closing operation for the first opening/closing valve  75   b  and a closing operation for the first atmosphere opening valve  76   a  on the display section  26  at the time of a step in which an opening/closing operation for each valve is required. 
     The routine illustrated in  FIG.  6    is a routine related to the liquid filling operation in which the liquid ejection apparatus  11  fills the liquid ejection head  54  with one type of liquid. In the present embodiment, as described above, the liquid supply unit  27  included in the liquid ejection apparatus  11  stores a plurality of liquid storage bodies  28  respectively storing a plurality of types of liquids L. The liquids L stored in the plurality of liquid storage bodies  28  are respectively supplied to the in-head flow paths of the liquid ejection head  54 . Thus, the liquid ejection apparatus  11  similarly executes the liquid filling operation of performing filling with all the liquids L supplied to the liquid ejection head  54 . 
     After the liquid filling operation, it is desirable that an operation of discharging the liquid L in the cap portion  73  or an operation of cleaning the nozzle surface  54   b  is performed as maintenance of the liquid ejection head  54 . Thus, the liquid ejection head replacement flow includes a maintenance step in which the maintenance section  71  performs maintenance of the liquid ejection head  54 . There are two types of maintenance such as automatic maintenance and manual maintenance. Maintenance that is automatically performed by the control section  70  based on information from each constituent of the liquid ejection apparatus  11  without any intervention of a user&#39;s operation is referred to as the automatic maintenance. Maintenance performed by the control section  70  in response to the user&#39;s start instruction from the operation section  25  is referred to as the manual maintenance. 
     In the manual maintenance, the control section  70  starts a maintenance flow on the display section  26 . For example, first, the control section  70  allows the user to press a button for starting the manual maintenance. When the manual maintenance is finished, the control section  70  may display, on the display section  26 , a method of starting nozzle check printing following the manual maintenance. The nozzle check printing is a process in which the control section  70  causes the liquid ejection apparatus  11  to print a specific test pattern on the medium M in order for the user to check the presence or absence of defective ejection in the nozzles  54   a  of the liquid ejection head  54 . When the nozzle check printing is finished, the control section  70  displays a selection screen including “recovered” and “not recovered” from a problem related to ejection on the display section  26 , and allows the user to select either of the two. The control section  70  performs a process corresponding to the result selected by the user. When the user selects “not recovered”, the control section  70  may display, on the display section  26 , a selection screen regarding whether or not the maintenance flow is started again on the display section  26 . 
     Also in the automatic maintenance, the maintenance flow may be automatically executed. For example, when the automatic maintenance is finished, the control section  70  automatically performs the nozzle check printing. When the nozzle check printing is finished, the control section  70  may display a selection screen including “recovered” and “not recovered” from a problem related to ejection on the display section  26 , and allow the user to select either of the two. The control section  70  may perform a process corresponding to the result selected by the user. 
     In both the automatic maintenance and the manual maintenance, processes in the flowchart of  FIG.  7    are performed by the control section  70 . In the present embodiment, the automatic maintenance is performed after the liquid filling operation. A subroutine of the maintenance step for the liquid ejection head  54  will be described with reference to the flowchart of  FIG.  7   . 
     In step S 301 , the control section  70  executes suction cleaning. The suction cleaning is an operation of sucking air bubbles or foreign substances in the nozzle  54   a  together with the liquid L from the nozzle  54   a . The control section  70  performs suction with the suction pump  73   b  for a predetermined time in which the carriage unit  50  is moved to the home position HP and the cap portion  73  is located at the contact position. When the suction is finished, the control section  70  moves the cap portion  73  to the retreat position. 
     When the suction cleaning is executed, the liquid L discharged from the nozzle  54   a  may adhere to the nozzle surface  54   b  of the liquid ejection head  54 . Thus, wiping may be executed after the suction cleaning is executed. Consequently, the liquid L adhering to the nozzle surface  54   b  through the suction cleaning can be removed through the wiping. 
     In step S 302 , the control section  70  executes the wiping after performing the suction cleaning. The control section  70  moves the carriage unit  50  to a wiping position and executes the wiping. When the wiping is executed by the wiping member, foreign substances, air bubbles, or the like adhering to the liquid ejection head  54  may be pushed into the nozzle  54   a . In this case, there is concern that the meniscus in the nozzle  54   a  may be destroyed, or defective ejection of the nozzle  54   a  may occur. Thus, after the wiper unit executes the wiping, the control section  70  may cause the flushing unit to execute flushing. 
     In step S 303 , the control section  70  moves the carriage unit  50  to a flushing position and causes the flushing unit to perform flushing. Consequently, foreign substances mixed in the nozzle  54   a  can be discharged, or the meniscus in the nozzle  54   a  can be adjusted. 
     In the present embodiment, after the liquid ejection head  54  is replaced and the liquid filling operation is performed, the suction cleaning, the wiping, and the flushing are performed as maintenance of the liquid ejection head  54 , but only the suction cleaning may be performed. When the liquid filling operation includes the suction cleaning function, the control section  70  does not have to perform the suction cleaning after the liquid filling operation. 
     Detector that Detects Defective Ejection 
     As illustrated in  FIG.  8   , in the present embodiment, the carriage unit  50  included in the liquid ejection apparatus  11  has a monitoring section  55  that monitors an ejection state in the liquid ejection head  54 . 
     The monitoring section  55  may employ various monitoring methods. In the present embodiment, a method of acquiring residual vibration information of a liquid chamber in the liquid ejection head  54  is employed. As an example, in the liquid ejection head  54  having a piezoelectric element (not illustrated), the monitoring section  55  outputs a drive signal for changing a volume of the liquid chamber within a range in which the liquid L is not ejected from the nozzle  54   a  illustrated in  FIG.  4    to the piezoelectric element, and monitors an ejection state of the liquid L at each nozzle by acquiring the residual vibration information of the liquid chamber detected by the piezoelectric element. 
     As a monitoring method, other methods may be employed. For example, a method may be employed in which the liquid L ejected from the nozzle  54   a  illustrated in  FIG.  4    of the liquid ejection head  54  is irradiated with light from a light source to generate scattered light, and it is determined whether or not ejection is normal by acquiring a value of an output voltage from a light receiving element that receives the scattered light. A method may be employed in which the liquid L ejected from each nozzle  54   a  of the liquid ejection head  54  is ejected onto an electrostatic sensor, and it is determined whether or not ejection from each nozzle  54   a  is normal by acquiring a value of a capacitance from a capacitance detector of the electrostatic sensor. A method may be employed in which nozzle check printing is executed in response to a user&#39;s instruction from the operation section  25  or by the control section  70  periodically, the user determines whether or not ejection is normal based on a printing result of the nozzle check printing, the determination result is input by the operation section  25 , and the control section  70  acquires the determination result from the operation section  25 . 
     In the present embodiment, the control section  70  includes a detector  70   a  having a function of detecting defective ejection of the liquid ejection head  54 . The monitoring section  55  monitors whether or not defective ejection has occurred in the liquid ejection head  54  at all times, and notifies the detector  70   a  of a monitoring result. The control section  70  executes the automatic maintenance of the liquid ejection head  54  by the maintenance section  71  illustrated in  FIG.  2    in accordance with the result of which the detector  70   a  is notified from the monitoring section  55 . That is, the control section  70  performs the automatic maintenance that causes the maintenance section  71  to automatically perform maintenance when the detector  70   a  detects defective ejection. 
     The detector  70   a  detects a problem related to ejection of the liquid ejection head  54 . In the present embodiment, the detector  70   a  also detects a maintenance status of the liquid ejection head  54  executed by the maintenance section  71 . When the detector  70   a  detects that the automatic maintenance has been repeatedly executed a predetermined number of times or more by the control section  70 , it is determined that the liquid ejection head  54  has a problem related to ejection. More specifically, in the present embodiment, when it is detected that an operation of executing the automatic maintenance in accordance with a result of which a notification is sent from the monitoring section  55  after the whole of one print job is finished has been repeatedly executed a plurality of times, the detector  70   a  determines that a problem related to ejection has occurred. That is, the detector  70   a  detects that the automatic maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. 
     The detector  70   a  also determines that the liquid ejection head  54  has a problem related to ejection when it is detected that the manual maintenance has been repeatedly executed a predetermined number of times or more by the user. More specifically, in the present embodiment, when it is detected that an operation of the user executing the manual maintenance after the whole of one print job is finished has been repeatedly executed a plurality of times, the detector  70   a  determines that a problem related to ejection has occurred. That is, the detector  70   a  detects that the maintenance has been repeatedly executed by the user a predetermined number of times or more as a problem related to ejection. 
     In the present embodiment, when the user finds that the liquid ejection head  54  has a problem related to ejection, the user can operate a menu displayed on the display section  26  by using the operation section  25 , to input the occurrence of a problem related to ejection from the operation section  25  as an example of an input section. That is, the liquid ejection apparatus  11  includes an input section that allows the user to input the occurrence of a problem related to ejection. The detector  70   a  determines that the liquid ejection head  54  has a problem related to ejection even when the user inputs the occurrence of the problem related to ejection by using the operation section  25 . 
     Configuration of Delivery System 
     As illustrated in  FIG.  8   , the liquid ejection apparatus  11  includes a transmission section  60  that is controlled by the control section  70  to transmit a signal. The transmission section  60  is coupled to a network NW in a wireless or wired manner. 
     The control section  70  is configured to acquire model information regarding the liquid ejection head  54  and ejection-related problem history information of the liquid ejection head  54 . The model information and the ejection-related problem history information are stored in an IC chip  56  included in the liquid ejection head  54 . As will be described in detail later, the ejection-related problem history information is the number of times for which the automatic maintenance is repeatedly executed and the number of times for which the manual maintenance is repeatedly executed by the user. The control section  70  is electrically coupled to the IC chip  56  of the liquid ejection head  54  attached to the carriage unit  50 . 
     The liquid ejection apparatus  11  configures a part of a delivery system  100 . That is, the delivery system  100  includes the liquid ejection apparatus  11  and a server apparatus  80  on the network NW. The server apparatus  80  includes a reception section  80   a  that receives information transmitted from the transmission section  60  of the liquid ejection apparatus  11 . The delivery system  100  may have a plurality of liquid ejection apparatuses  11 , and the plurality of liquid ejection apparatuses  11  may be coupled to the server apparatus  80 . Each liquid ejection apparatus  11  is communicably coupled to the server apparatus  80  via the network NW. 
     The liquid ejection head  54  in which a problem related to ejection has occurred needs to be replaced. When the detector  70   a  detects a problem related to ejection, the control section  70  may cause the transmission section  60  to transmit a delivery request for a new liquid ejection head to the server apparatus  80  via the network NW. The server apparatus  80  may cause the reception section  80   a  to receive the delivery request for the new liquid ejection head transmitted from the control section  70  via the network NW. That is, the server apparatus  80  has the reception section  80   a  that receives the delivery request for the new liquid ejection head transmitted from the control section  70 . 
     The delivery system  100  delivers a new replacement liquid ejection head  54  to replace the liquid ejection head  54  that needs to be replaced in the liquid ejection apparatus  11  to a user using the liquid ejection apparatus  11 . In this case, the control section  70  may cause the transmission section  60  to transmit a delivery request for a new liquid storage body to the server apparatus  80  via the network NW. That is, the server apparatus  80  may prepare for delivery of the new liquid storage body when receiving a request signal for the delivery of the new replacement liquid storage body transmitted from the liquid ejection apparatus  11 . 
     Even when the control section  70  does not detect a problem related to ejection, the delivery system  100  may deliver the replacement liquid ejection head  54  to the user using the liquid ejection apparatus  11  in response to the user&#39;s instruction from the operation section  25 . The delivery system  100  may deliver the new liquid storage body  28  to the user using the liquid ejection apparatus  11  in response to the user&#39;s instruction from the operation section  25 . 
     Ejection-Related Problem Determination Process 
     With reference to a flowchart of  FIG.  9   , a description will be made of an example of control executed by the control section  70  in the “ejection-related problem determination process” for the liquid ejection head  54 . The present routine is executed at a timing immediately after power of the liquid ejection apparatus  11  is turned on by operating the power switch  25   a  and an initialization operation for the liquid ejection apparatus  11  is performed, or is executed at a timing at which the liquid ejection head  54  is attached to the carriage unit  50  in a state in which the power is turned on. 
     In step S 600 , the control section  70  executes a subroutine of a “new liquid ejection head attachment check process” illustrated in  FIG.  11   . The subroutine of the “new liquid ejection head attachment check process” will be described later. 
     In step S 401 , the control section  70  determines whether or not ejection of the liquid ejection head  54  is determined as being normal. More specifically, the control section  70  determines whether or not a flag of “problem occurrence related to ejection” described later is set. In the liquid ejection head  54 , when a problem related to ejection has already occurred, the power switch  25   a  may be temporarily turned off, and then the power switch  25   a  may be turned on again. Thus, the determination in this step S 401  is required at the timing at which the power is turned on. That is, at the timing at which the power is turned on, the detector  70   a  of the control section  70  may determine that a problem related to ejection has already occurred. When the ejection of the liquid ejection head  54  is normal, a determination result in step S 401  is YES, and the process proceeds to step S 402 . When the ejection of the liquid ejection head  54  is determined as not being normal, a determination result in step S 401  is NO, and the process proceeds to step S 407  described later. 
     In step S 402 , the control section  70  determines whether or not defective ejection of the liquid ejection head  54  is detected by the detector  70   a . When defective ejection is detected, a determination result in step S 402  is YES, and the process proceeds to step S 403 . When defective ejection is not detected, the determination result in step S 402  is NO, and the process proceeds to step S 408 . 
     In step S 403 , the control section  70  causes the maintenance section  71  to start maintenance of the liquid ejection head  54  at a timing at which a print job is finished. The maintenance executed in this step is automatic maintenance performed automatically without any intervention of the user. 
     In step S 300 , the control section  70  executes the subroutine of the maintenance process illustrated in  FIG.  7   . 
     In step S 404 , the control section  70  adds 1 to the number of times for which the automatic maintenance is repeatedly executed at a timing at which the automatic maintenance is finished. The control section  70  has, for example, a rewritable memory therein, and reads a plurality of pieces of information in the IC chip  56  of the liquid ejection head  54  attached to the liquid ejection apparatus  11  and stores the information into the memory to share the information with the IC chip  56 . The IC chip  56  stores, for example, the model information and the ejection-related problem history of the liquid ejection head  54 . The model information is a model number, a serial number, or the like of the liquid ejection head  54 , and is used for the control section  70  to identify the liquid ejection head  54 . The control section  70  can determine whether or not the attached liquid ejection head  54  can be used in the liquid ejection apparatus  11  without any problem based on the model information. The ejection-related problem history is the number of times for which the automatic maintenance is repeatedly performed, the number of times for which the manual maintenance is repeatedly performed, and the like in the attached liquid ejection head  54 . 
     When the automatic maintenance is performed for the first time in this step S 404  after the new liquid ejection head  54  is attached to the liquid ejection apparatus  11 , the numerical value “zero” stored in the IC chip  56  as the number of times for which the automatic maintenance is repeatedly executed is rewritten to 1. The control section  70  shares the numerical value in the internal memory and the numerical value in the IC chip  56  with the number of times for which the automatic maintenance is repeatedly executed as 1. 
     In the next print job after the automatic maintenance is performed, when the detector  70   a  does not detect defective ejection and the automatic maintenance is not performed, the numerical value “1” stored in the IC chip  56  as the number of times for which the automatic maintenance is repeatedly executed is rewritten to “zero”. The control section  70  shares the numerical value in the internal memory and the numerical value in the IC chip  56  with the number of times for which the automatic maintenance is repeatedly executed as “zero”. Thus, even when the liquid ejection head  54  has undergone the automatic maintenance in this step S 404 , the numerical value stored in the IC chip  56  may be “zero” as the number of times for which the automatic maintenance has been repeatedly performed. In the following description, the number of times for which the automatic maintenance is repeatedly performed will be referred to as the number of times of the automatic maintenance. 
     In step S 405 , the detector  70   a  of the control section  70  determines whether or not the number of times of the automatic maintenance has reached a first specified number of times N1. That is, the detector  70   a  detects that the automatic maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. When the number of times of the automatic maintenance has reached the first specified number of times N1, a determination result in step S 405  is YES, and the process proceeds to step S 406 . When the number of times of the automatic maintenance has not reached the first specified number of times N1, a determination result in step S 405  is NO, and the process proceeds to step S 402 . The first specified number of times N1 differs depending on the type of the liquid ejection head  54  and thus is not limited, but is, for example, three. The first specified number of times N1 may be more or less than three. In a case where the first specified number of times N1 is three, the determination result in step S 405  is YES when the number of times of the automatic maintenance has reached three, and the process proceeds to step S 406 . 
     In step S 406 , the detector  70   a  of the control section  70  determines that the liquid ejection head  54  has a problem related to ejection. The control section  70  sets a flag of “problem occurrence related to ejection” in the rewritable memory therein. For example, a numerical value of a portion storing the presence or absence of “problem occurrence related to ejection” is rewritten from “zero” to 1. The control section  70  may also perform writing in the IC chip  56  of the liquid ejection head  54 , and rewrite the numerical value of the portion storing the presence or absence of “problem occurrence related to ejection” from “zero” to 1, to share information between the internal memory of the control section  70  and the IC chip  56 . 
     Then, in step S 500 , as the details will be described later, the control section  70  executes a subroutine of a check flow including a delivery request for a new liquid ejection head. That is, when the detector  70   a  detects a problem related to ejection in the liquid ejection head  54 , the control section  70  starts a check flow including a delivery request for a new liquid ejection head. 
     In the present embodiment, instead of starting the above check flow, the control section  70  may automatically transmit a delivery request for a new liquid ejection head to the server apparatus  80  without starting the check flow when the detector  70   a  detects a problem related to ejection in the liquid ejection head  54 . 
     When the subroutine of the above check flow is finished, the control section  70  finishes the present flow illustrated in  FIG.  9   . 
     As described above, when the ejection of the liquid ejection head  54  is determined as not being normal in step S 401 , a determination result in step S 401  is NO, and the process proceeds to step S 407 . 
     In step S 407 , the control section  70  determines whether or not the delivery request for the new liquid ejection head has been transmitted. When the delivery request for the new liquid ejection head has been transmitted, a determination result in step S 407  is YES, and the control section  70  finishes the present flow illustrated in  FIG.  9   . That is, when the delivery request for the new liquid ejection head has already been transmitted, the control section  70  does not need to perform the check flow including the delivery flow. For example, when the power switch  25   a  is temporarily turned off and the power switch  25   a  is turned on again after the delivery request for the new liquid ejection head is transmitted, the control section  70  has transmitted the delivery request for the new liquid ejection head. When the control section  70  has not transmitted the delivery request for the new liquid ejection head, a determination result in step S 412  is NO, and the process proceeds to step S 500 . For example, when the check flow is started by the control section  70 , and the power switch  25   a  is temporarily turned off and the power switch  25   a  is turned on again before the delivery request for the new liquid ejection head is transmitted, the control section  70  has not transmitted the delivery request for the new liquid ejection head. In this case, the delivery request for the new liquid ejection head needs to be transmitted. That is, the control section  70  restarts the check flow including the delivery request for the new liquid ejection head. 
     As described above, when the defective ejection is not detected in step S 402 , the determination result in step S 402  is NO, and the control section  70  proceeds to a process in step S 408 . 
     In step S 408 , the control section  70  determines whether or not manual maintenance of the liquid ejection head  54  has been performed by the user. When the manual maintenance of the liquid ejection head  54  has been performed by the user, a determination result in step S 408  is YES, and the process proceeds to step S 409 . When the manual maintenance of the liquid ejection head  54  has not been performed by the user, the determination result in step S 408  is NO, and the process proceeds to step S 411 . 
     In step S 409 , the control section  70  adds 1 to the number of times for which the manual maintenance has been repeatedly performed at a timing at which the manual maintenance is finished. When the manual maintenance is performed for the first time in this step S 409  after the new liquid ejection head  54  is attached to the liquid ejection apparatus  11 , the numerical value “zero” stored in the IC chip  56  as the number of times for which the manual maintenance is repeatedly executed is rewritten to 1. The control section  70  shares the numerical value in the internal memory and the numerical value in the IC chip  56  with the number of times of the manual maintenance as 1. 
     In the first print job after the manual maintenance is performed by the user, when the manual maintenance is not performed, the numerical value “1” stored in the IC chip  56  as the number of times for which the manual maintenance is repeatedly performed is rewritten to “zero”. The control section  70  shares the numerical value in the internal memory and the numerical value in the IC chip  56  with the number of times for which the manual maintenance is repeatedly performed as “zero”. Even in a case where the manual maintenance has been performed in this step S 409  after the new liquid ejection head  54  is attached to the liquid ejection apparatus  11 , when the manual maintenance has not been performed after the previous print job, the numerical value stored in the IC chip  56  is “zero” as the number of times for which the manual maintenance has been repeatedly performed. In the following description, the number of times for which the manual maintenance is repeatedly performed will be referred to as the number of times of the manual maintenance. 
     In step S 410 , the detector  70   a  of the control section  70  determines whether or not the number of times of the manual maintenance has reached a second specified number of times N2. That is, the detector  70   a  detects that the manual maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. When the number of times of the manual maintenance has reached the second specified number of times N2, a determination result in step S 410  is YES, and the process proceeds to step S 406 . When the number of times of the manual maintenance has not reached the second specified number of times N2, the determination result in step S 410  is NO, and the process proceeds to step S 402 . The second specified number of times N2 differs depending on the type of the liquid ejection head  54  and thus is not limited, but is, for example, three. The second specified number of times N2 may be more or less than three. The second specified number of times N2 may be the same value as the first specified number of times N1 or may be a value different from the first specified number of times N1. In a case where the second specified number of times N2 is three, when the number of times of the manual maintenance times has reached three, the determination result in step S 410  is YES, and the process proceeds to step S 406 . 
     In the present embodiment, the detector  70   a  counts the number of times of the automatic maintenance and the number of times of the manual maintenance separately, but the detector  70   a  may determine whether or not a sum of the number of times of the automatic maintenance and the number of times of the manual maintenance has reached a specified number of times. The control section  70  may determine whether or not a problem related to ejection has occurred based on a determination result of whether or not the sum of the number of times of the automatic maintenance and the number of times of the manual maintenance has reached the specified number of times. In this case, when the automatic maintenance is executed after the previous print job and the manual maintenance is executed after the next print job, or when the manual maintenance is executed after the previous print job and the automatic maintenance is executed after the next print job, the detector  70   a  may determine that maintenance has been repeatedly executed. 
     As described above, when the manual maintenance of the liquid ejection head  54  has not been performed by the user in step S 408 , the determination result in step S 408  is NO, and the control section  70  proceeds to a process in step S 411 . 
     In step S 411 , the control section  70  determines whether or not the user has input the occurrence of the problem related to ejection by using the operation section  25  as an example of an input section. When the user has input the occurrence of the problem related to ejection to the operation section  25 , a determination result in step S 411  is YES, and the process proceeds to step S 406 . That is, when the occurrence of the problem related to ejection of the liquid ejection head  54  has been input by using the operation section  25 , the control section  70  starts a check flow including a delivery request for a new liquid ejection head. When the user has not input the occurrence of the problem related to ejection to the operation section  25 , the determination result in step S 411  is NO, and the process proceeds to step S 412 . 
     In step S 412 , the control section  70  determines whether or not the user has input a delivery request for a new liquid ejection head by using the operation section  25  as an example of an input section. When the user has input the delivery request for the new liquid ejection head to the operation section  25 , a determination result in step S 412  is YES, and the process proceeds to step S 406 . That is, even when the user has input the delivery request for the new liquid ejection head by using the operation section  25 , this is included in the input of the occurrence of the problem related to ejection to the operation section  25 , performed by the user. When the user has not input the delivery request for the new liquid ejection head to the operation section  25 , the determination result in step S 412  is NO, and the process proceeds to step S 402 . 
     Check Flow 
     First, an outline of the check flow illustrated in  FIG.  10    will be described. 
     When the control section  70  determines that a problem related to ejection has occurred, the occurrence of the problem may be determined by the detector  70   a  detecting a state of the liquid ejection apparatus  11  and by a user inputting the occurrence of the problem by using operation section  25 . When the user inputs the occurrence of a problem related to ejection in step S 411  in  FIG.  9   , or when the user inputs a delivery request for a new liquid ejection head in step S 412  in  FIG.  9   , the control section  70  determines that a problem related to ejection has occurred by the user inputting the occurrence of the problem related to ejection by using operation section  25 . 
     The user may input the occurrence of a problem related to ejection or a delivery request for a new liquid ejection head to the operation section  25  without knowing that the liquid ejection head  54  can be manually maintained in the liquid ejection apparatus  11 . Thus, it is desirable that the control section  70  starts a check flow according to a maintenance execution status for the liquid ejection head  54  in the liquid ejection apparatus  11 . Consequently, the control section  70  starts the check flow according to the maintenance execution status for the liquid ejection head  54  before the user inputs the occurrence of a problem or the delivery request by using the operation section  25  as an example of an input section. 
     More specifically, in the present embodiment, when the user inputs the occurrence of a problem related to ejection or the delivery request for a new liquid ejection head to the operation section  25 , in a case where the number of times of the manual maintenance is equal to or larger than the third specified number of times N3, the control section  70  proceeds to the delivery flow. When the user inputs the occurrence of a problem related to ejection or the delivery request for a new liquid ejection head to the operation section  25 , in a case where the number of times of the manual maintenance is smaller than the third specified number of times N3, the control section  70  performs the automatic maintenance, and then the control section  70  proceeds to the delivery flow when a recovery from the problem related to ejection is not made through the automatic maintenance. 
     When the user inputs the occurrence of a problem related to ejection or a delivery request for a new liquid ejection head to the operation section  25  without knowing that the liquid ejection head  54  can be manually maintained in the liquid ejection apparatus  11 , a recovery from the problem related to ejection may be made through the automatic maintenance. For example, in a case where the user inputs the occurrence of the problem related to ejection to the operation section  25  without knowing that the liquid ejection head  54  can be manually maintained in the liquid ejection apparatus  11 , when a recovery from the problem is made through maintenance, a new liquid ejection head  54  does not need to be delivered. That is, the control section  70  does not need to proceed to the delivery flow. Thus, the control section  70  causes the maintenance section  71  to execute maintenance one or more times. 
     In the delivery flow, it is possible to request delivery of consumables at the same time. The control section  70  transmits a delivery request for a new liquid ejection head to the server apparatus  80 , and also transmits a delivery request for a new liquid storage body to the server apparatus  80 . 
     In the present embodiment, the control section  70  starts a check flow on the display section  26  of the liquid ejection apparatus  11 . Alternatively, the control section  70  may start the check flow on a PC screen coupled thereto via the network NW, or may start the check flow on both the PC screen and the display section  26  of the liquid ejection apparatus  11 . 
     Next, with reference to a flowchart of  FIG.  10   , control executed by the control section  70  in each step will be described in order for a subroutine of the check flow. 
     In step S 501 , the control section  70  determines whether or not the occurrence of a problem related to ejection or a delivery request has been input to the operation section  25  as an example of an input section. When the occurrence of a problem related to ejection or a delivery request has been input to the operation section  25 , and the control section  70  proceeds to the check flow, a determination result in step S 501  is YES, and the process proceeds to step S 502 . When the occurrence of a problem related to ejection or a delivery request has not been input to the operation section  25 , that is, the number of times of the automatic maintenance has reached the first specified number of times N1, or the number of times of maintenance performed by the user has reached the second specified number of times N2, and the control section  70  proceeds to the check flow, the determination result in step S 501  is NO, and the process proceeds to step S 503 . 
     In step S 502 , the detector  70   a  of the control section  70  determines whether or not the number of times of the manual maintenance has reached a third specified number of times N3. That is, the detector  70   a  detects that the manual maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. When the number of times of the manual maintenance has reached the third specified number of times N3, a determination result in step S 502  is YES, and the process proceeds to step S 503 . When the number of times of the manual maintenance has not reached the third specified number of times N3, the determination result in step S 502  is NO, and the process proceeds to step S 511 . The third specified number of times N3 differs depending on the type of the liquid ejection head  54  and thus is not limited, but is, for example, two. The third specified number of times N3 may be more or less than two. The third specified number of times N3 may be the same value as the first specified number of times N1 or the second specified number of times N2, or may be a value different from the first specified number of times N1 or the second specified number of times N2. In a case where the third specified number of times N3 is two, the determination result of step S 502  is YES when the number of times of the manual maintenance has reached two, and the process proceeds to step S 503 . When the number of times of the manual maintenance is “zero” or one, the determination result in step S 502  is NO, and the process proceeds to step S 511 . 
     The control section  70  may set step S 502  as a step of checking, with the user, whether or not the manual maintenance or nozzle check printing has been performed, by using the display section  26 . That is, the control section  70  may check, with the user, whether or not the manual maintenance or nozzle check printing has been performed by using the display section  26 , and when “performed” is selected by using the operation section  25 , the process may proceed to the delivery flow in step S 503 , and when “not performed” is selected, the process may proceed to step S 511 . 
     In step S 503 , the control section  70  displays a check screen regarding whether or not the new liquid ejection head  54  is to be delivered on the display section  26 . For example, the control section  70  displays a message including “a problem related to ejection has been detected; do you want to request delivery of a new liquid ejection head?” on the display section  26 , and requests the user to select and input “YES” or “NO” by using the operation section  25 . When the user inputs “YES” by using the operation section  25 , the control section  70  starts the delivery flow in step S 503 . 
     In step S 504 , the control section  70  determines whether or not a delivery request for a new liquid ejection head has been selected by using the operation section  25 . When the delivery request for the new liquid ejection head has been selected, a determination result in step S 504  is YES, and the process proceeds to step S 505 . When the delivery request for the new liquid ejection head has not been selected, the determination result in step S 504  is NO, and the process proceeds to step S 509 . When the user has already requested delivery of the new liquid ejection head, there may be a flow in which the control section  70  displays the fact on the display section  26  such that the user cannot request the delivery of the new liquid ejection head. 
     In step S 505 , as illustrated in  FIG.  8   , the control section  70  causes the transmission section  60  to transmit the delivery request for the new liquid ejection head to the server apparatus  80  via the network NW. The server apparatus  80  receives a transmission content from the transmission section  60  with the reception section  80   a , and receives the delivery request for the new liquid ejection head. The control section  70  displays a message including “replace with a new liquid ejection head” on the display section  26 , and prohibits use of the liquid ejection apparatus  11 . For example, in the present embodiment, when the delivery request for the new liquid ejection head is transmitted and the control section  70  finishes the delivery flow in step S 508  described later, the liquid ejection apparatus  11  does not accept any operation other than an operation on the power switch  25   a  from the operation section  25  and an operation related to a use prohibition cancellation process. That is, the control section  70  prohibits the use of the liquid ejection apparatus  11  when the delivery request for the new liquid ejection head is transmitted. 
     In step S 506 , the control section  70  displays, on the display section  26 , a check screen regarding whether or not to a new liquid storage body  28  for the liquid storage body  28  of the liquid ejection apparatus  11  is to be delivered. For example, the control section  70  displays a message including “do you want to request delivery of all new liquid storage bodies at the same time as the delivery of the new liquid ejection head?” on the display section  26 , and requests the user to select and input “YES” or “NO” by using the operation section  25 . The control section  70  determines whether or not the delivery request for all the new liquid storage bodies has been selected by the operation section  25 . When the delivery request for all new liquid storage bodies is selected, a determination result in step S 506  is YES, and the process proceeds to step S 507 . When the delivery request for all the new liquid storage bodies is not selected, the determination result in step S 506  is NO, and the process proceeds to step S 509 . The control section  70  may proceed to step S 509  after executing step S 505  without performing the process in step S 506 . 
     There is a case where nozzle check printing may be executed in the liquid ejection apparatus  11 , and the user may check a result of the nozzle check printing to determine which liquid storage body  28  a problem has occurred in a nozzle ejecting the liquid L supplied from. For example, when defective ejection has occurred in the yellow ink, there may be a problem with the yellow ink. In this case, it is desirable that a new liquid storage body  28  for the liquid storage body  28  storing the yellow ink in which the defective ejection has occurred is delivered. That is, in step S 506 , the control section  70  may display, on the display section  26 , a screen for selecting for which liquid storage body  28  a new liquid storage body  28  is to be delivered among the liquid storage bodies  28  of the liquid ejection apparatus  11 , and the control section  70  may allow the user to select for which liquid storage body  28  the new liquid storage body  28  is to be delivered. 
     In step S 507 , as illustrated in  FIG.  8   , the control section  70  causes the transmission section  60  to transmit a delivery request for the new liquid storage body to the server apparatus  80  via the network NW. When the detector  70   a  detects a problem related to ejection, the control section  70  may transmit a delivery request for a new liquid storage body in addition to the delivery request for the new liquid ejection head. The server apparatus  80  receives the transmission content from the transmission section  60  by using the reception section  80   a , and receives the delivery request for the new liquid storage body. 
     As in the present embodiment, the control section  70  may transmit a delivery request for all new liquid storage bodies to the server apparatus  80 , or may transmit a delivery request for a new liquid storage body for the liquid storage body  28  selected by the user to the server apparatus  80 . 
     In step S 508 , the control section  70  finishes the delivery flow. For example, when delivery of the new liquid ejection head  54  and all the new liquid storage bodies  28  has been requested, the control section  70  displays, on the display section  26 , a message including “delivery of the new liquid ejection head and all the new liquid storage bodies has been requested”, and finishes the delivery flow. The control section  70  finishes the subroutine of the check flow. 
     In step S 509 , the control section  70  determines whether or not there is the liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the liquid storage bodies  28  included in the liquid ejection apparatus  11 . For example, the liquid ejection apparatus  11  has a plurality of liquid residual amount sensors (not illustrated) each detecting a residual amount of the liquid L in each liquid storage body  28  in the liquid supply unit  27 , and the liquid residual amount sensor including a light projecting element and a light receiving element detects a residual amount of the liquid L based on an intensity of reflected light that changes according to the residual amount of the liquid L stored in each liquid storage body  28 . The control section  70  determines whether or not there is a liquid storage body  28  of which a residual amount of the liquid L stored in the liquid storage body  28  is less than a predetermined threshold value based on a signal that is input from the liquid residual amount sensor. For example, the threshold value is a value determined based on the number of days until the liquid storage body  28  arrives and an amount of the liquid L consumed in the liquid ejection apparatus  11  in a day. When there is the liquid storage body  28  of which the residual amount is less than the predetermined threshold value, a determination result in step S 509  is YES, and the process proceeds to step S 510 . When there is no liquid storage body  28  of which the residual amount is less than the predetermined threshold value, the determination result in step S 509  is NO, and the process proceeds to step S 508 . 
     In step S 510 , the control section  70  causes the transmission section  60  to transmit a delivery request for a new liquid storage body to the server apparatus  80  via the network NW with respect to the liquid storage body  28  of which the residual amount is less than the predetermined threshold value. When the detector  70   a  detects a problem, the control section  70  may transmit a delivery request for a new liquid storage body  28  corresponding to the liquid storage body  28  of which the residual amount is less than the predetermined threshold value in addition to the delivery request for the new liquid ejection head. That is, when a delivery request for a new liquid ejection head is made, in a case where there is a liquid storage body  28  of which the residual amount is less than the predetermined threshold value among the plurality of liquid storage bodies  28  storing the liquids L to be supplied to the liquid ejection head  54 , the control section  70  transmits the delivery request for the new liquid storage body in addition to the delivery request for the new liquid ejection head. 
     When the user has already requested the delivery of the new liquid storage body, the delivery request for the new liquid storage body does not need to be made. When there are a plurality of liquid storage bodies  28  in which residual amounts are less than the predetermined threshold value, the control section  70  may automatically a delivery request for new liquid storage bodies corresponding to the plurality of liquid storage bodies  28  to the server apparatus  80 . 
     In step S 508 , the control section  70  finishes the delivery flow. For example, when delivery of a new liquid ejection head  54  and a new liquid storage body  28  for the yellow ink has been requested, the control section  70  displays, on the display section  26 , a message including “delivery of a new liquid ejection head and a new liquid storage body for the yellow ink has been requested”, and finishes the delivery flow. The control section  70  finishes the subroutine of the check flow. 
     As described above, when the number of times of the manual maintenance has not reached the third specified number of times N3, the determination result in step S 502  is NO, and the control section  70  proceeds to a process in step S 511 . 
     In step S 511 , the control section  70  causes the maintenance section  71  to start executing the automatic maintenance of the liquid ejection head  54 . In step S 511 , the control section  70  may proceed to a flow for executing the manual maintenance. The manual maintenance may be started by the user operating the operation section  25 . 
     In step S 300 , the control section  70  executes the above-described maintenance subroutine illustrated in  FIG.  7   . 
     In step S 512 , the control section  70  causes the carriage unit  50  to execute nozzle check printing. The purpose of the nozzle check printing after the automatic maintenance is to allow the user to check whether or not a recovery from a problem related to ejection has been made through the automatic maintenance when the number of times of the manual maintenance performed by the user is small. 
     In step S 513 , the control section  70  displays a selection screen including “recovered” and “not recovered” from the problem related to ejection on the display section  26 . The user looks at a result of the nozzle check printing and selects either “recovered” or “not recovered”. 
     In step S 514 , the control section  70  determines whether or not “recovered” is selected by using the operation section  25 . When “recovered” is selected, a determination result in step S 514  is YES, and the control section  70  finishes the subroutine of the check flow. When “recovered” is not selected, that is, when “not recovered” is selected, the determination result in step S 514  is NO, and the process proceeds to the delivery flow in step S 503 . The control section  70  displays a check screen regarding whether or not the new liquid ejection head  54  is to be delivered on the display section  26 . 
     When “not recovered” is selected in step S 514 , the control section  70  may proceed to step S 511  and perform the automatic maintenance process again. In this case, in a case where “not recovered” is selected even when the automatic maintenance process is repeatedly executed a predetermined number of times, the control section  70  proceeds to the delivery flow in step S 503 . 
     In step S 513 , the control section  70  displays the selection screen including “recovered” and “not recovered” from the problem related to ejection on the display section  26 , and, in step S 514 , the control section  70  determines whether or not “recovered” is selected by using the operation section  25 . Alternatively, the detector  70   a  may automatically detect defective ejection. The control section  70  may determine whether or not a recovery from the problem related to ejection has been made according to a detection result. When it is determined that the recovery has been made, the control section  70  finishes the subroutine of the check flow. When it is determined that the recovery has not been made, the process proceeds to the delivery flow of step S 503 . 
     New Liquid Ejection Head Attachment Check Process 
     Next, with reference to a flowchart of  FIG.  11   , a description will be made of a subroutine of the “new liquid ejection head attachment check process” that is first executed by the control section  70  in the “ejection-related problem determination process” illustrated in  FIG.  9   . 
     In step S 601 , the control section  70  determines whether or not the delivery request for the new liquid ejection head has been transmitted. When the delivery request for the new liquid ejection head has been transmitted, a determination result in step S 601  is YES, and the process proceeds to step S 602 . When the delivery request for the new liquid ejection head has not been transmitted, or when the new liquid ejection head  54  delivered due to the delivery request has been attached and the delivered new liquid ejection head  54  has already begun to be used, the determination result in step S 601  is NO, and the control section  70  finishes the present subroutine. 
     In step S 602 , the control section  70  acquires the model information of the liquid ejection head  54  included in the carriage unit  50  and the ejection-related problem history information from the IC chip  56  of the liquid ejection head  54 . 
     In step S 603 , when a message including “the replaced liquid ejection head is a used liquid ejection head” or “replace with a new liquid ejection head” on the display section  26  is displayed, the control section  70  deletes the message. This message will be described in step S 605  described later and step S 607  described later. 
     In step S 604 , the control section  70  determines whether or not the model information of the liquid ejection head  54  has been changed. As described above, the control section  70  identifies the liquid ejection head  54  based on the model information. That is, the control section  70  can check whether or not the liquid ejection head  54  has been replaced based on the model information. When the model information of the liquid ejection head  54  has been changed, a determination result in step S 604  is YES, and the process proceeds to step S 606 . When the model information of the liquid ejection head  54  has not been changed, the determination result in step S 604  is NO, and the process proceeds to step S 605 . When the liquid ejection head  54  is mounted on the liquid ejection apparatus  11  for the first time, the process proceeds to step S 606 . 
     In step S 605 , the control section  70  displays a message including “replace with a new liquid ejection head” on the display section  26 , and prohibits the use of the liquid ejection apparatus  11 . For example, the liquid ejection apparatus  11  does not accept any operation other than an operation on the power switch  25   a  from the operation section  25  and an operation related to a use prohibition cancellation process. The control section  70  finishes the present subroutine while the use of the liquid ejection apparatus  11  is prohibited. 
     When the power switch  25   a  is temporarily turned off and is then turned on again by the user operating the operation section  25  in a state in which the liquid ejection apparatus  11  prohibits the use of the liquid ejection apparatus  11 , the control section  70  performs an operation of initializing the liquid ejection apparatus  11 , and then executes the “ejection-related problem determination process” illustrated in  FIG.  9   . Thus, the control section  70  immediately proceeds to the present routine that is a first process in the “ejection-related problem determination process”. The control section  70  displays the message including “replace with a new liquid ejection head” again on the display section  26 , and does not accept any operation other than an operation on the power switch  25   a  from the operation section  25  and an operation related to a use prohibition cancellation process described later. That is, the control section  70  prohibits the use of the liquid ejection apparatus  11  when the delivery request for the new liquid ejection head is transmitted. 
     In the liquid ejection apparatus  11 , in a state in which the liquid ejection apparatus  11  prohibits the use of the liquid ejection apparatus  11 , the user can perform an operation related to the use prohibition cancellation process by using the operation section  25 . For example, in the present embodiment, in a state in which the liquid ejection apparatus  11  prohibits the use of the liquid ejection apparatus  11 , the control section  70  allows only a menu for managing the operation of the liquid ejection apparatus  11  to be operable on the display section  26 . Consequently, the user can select “apparatus use prohibition cancellation” from the menu by operating the operation section  25 . In a state in which the liquid ejection apparatus  11  prohibits the use of the liquid ejection apparatus  11 , when the user performs an operation of canceling the prohibition by using the operation section  25 , the control section  70  cancels the prohibition of the use of the liquid ejection apparatus  11  while displaying the message including “replaces with a new liquid ejection head” on the display section  26 . That is, the control section  70  cancels the prohibition of the use of the liquid ejection apparatus  11  after transmission of the delivery request for the new liquid ejection head on condition of the request from the user. 
     In step S 605 , after the control section  70  displays the message including “replace with a new liquid ejection head” on the display section  26 , the control section  70  may allow the user to select whether to prohibit the use of the liquid ejection apparatus  11  or to continue the use of the liquid ejection apparatus  11  by using the operation section  25 . 
     As described above, in step S 604 , when the model information of the liquid ejection head  54  has been changed, the determination result in step S 604  is YES, and the control section  70  proceeds to a process in step S 606 . 
     In step S 606 , the control section  70  determines whether or not the liquid ejection head  54  has an ejection-related problem history. When the model information of the liquid ejection head  54  is changed, in a case where the liquid ejection head  54  has the ejection-related problem history, the control section  70  determines that the liquid ejection head  54  has been replaced with another used liquid ejection head  54  having a problem related to ejection. When the liquid ejection head  54  has the ejection-related problem history, a determination result in step S 606  is YES, and the process proceeds to step S 607 . When the liquid ejection head  54  has no ejection-related problem history, the determination result in step S 606  is NO, and the process proceeds to step S 608 . 
     In step S 607 , the control section  70  displays a message including both “replace with a new liquid ejection head” and “the replaced liquid ejection head is a used liquid ejection head” on the display section  26 , and prohibits the use of the liquid ejection apparatus  11 . Even when the power switch  25   a  of the operation section  25  is temporarily turned off and is then turned on again by the user, the message is displayed again on the display section  26 . The control section  70  finishes the present subroutine while the use of the liquid ejection apparatus  11  is prohibited. 
     In step S 607 , when the number of times of the automatic maintenance of the attached liquid ejection head  54  has not reached the first specified number of times N1 and the number of times of the manual maintenance has not reached the second specified number of times N2, the control section  70  may cancel the prohibition of the use of the liquid ejection apparatus  11  such that the liquid ejection apparatus  11  can be used, and finish the present subroutine. 
     As described above, in step S 606 , when the liquid ejection head  54  has no ejection-related problem history, the determination result in step S 606  is NO, and the process proceeds to step S 608 . 
     In step S 608 , the control section  70  resets the ejection-related problem history stored in the control section  70 , and initializes the ejection-related problem flag. For example, the control section  70  rewrites a numerical value of a portion that stores the presence or absence of “problem occurrence related to ejection” from 1 to “zero”. That is, when the model information of the liquid ejection head  54  is changed and the liquid ejection head  54  has no ejection-related problem history, the control section  70  determines that the liquid ejection head  54  has been replaced with a new liquid ejection head  54 . 
     In step S 609 , the control section  70  deletes the message including “replace with a new liquid ejection head” displayed on the display section  26 , and cancels the prohibition of the use of the liquid ejection apparatus  11 . The control section  70  finishes the present subroutine. 
     An operation of the present embodiment will be described. 
     In the liquid ejection apparatus  11 , when the power switch  25   a  is turned on by the user, the control section  70  starts the flow illustrated in  FIG.  9    at a timing immediately after the initialization operation is performed, and first executes the “new liquid ejection head attachment check process” illustrated in  FIG.  11   . 
     The control section  70  shares the model information written in the IC chip  56  of the liquid ejection head  54  and the ejection-related problem history with the information in the memory in the control section  70 . The control section  70  checks, based on the model information, whether or not the liquid ejection head  54  has been replaced with another liquid ejection head  54  and also checks compatibility with the liquid ejection apparatus  11 . The control section  70  checks whether or not the liquid ejection head  54  has been replaced with a new liquid ejection head  54  based on the ejection-related problem history. 
     When a problem related to ejection has occurred in the liquid ejection head  54  attached to the liquid ejection apparatus  11 , the control section  70  checks whether or not the liquid ejection head  54  has been replaced with another liquid ejection head  54 . Consequently, printing can be performed with the liquid ejection head  54  different from the liquid ejection head  54  in which the problem related to ejection has occurred. That is, in the liquid ejection apparatus  11 , there is less concern that defective ejection may occur. 
     The control section  70  checks the compatibility, and thus the control section  70  can prevent the liquid ejection apparatus  11  from performing printing when the incompatible liquid ejection head  54  is attached. For example, when it is found after sending that a liquid ejection head  54  having a certain serial number causes a problem in a case of being attached to a specific liquid ejection apparatus, in a case where the liquid ejection head  54  having the serial number that may cause the problem is attached to the corresponding liquid ejection apparatus, the control section  70  can prohibit the use of the liquid ejection apparatus  11 . 
     The ejection-related problem history is checked, and thus it is possible to prevent the liquid ejection head  54  from being replaced with the liquid ejection head  54  having a problem related to ejection when the liquid ejection head  54  is replaced with another liquid ejection head  54 . That is, since the control section  70  can check whether or not the liquid ejection head  54  has been replaced with the new liquid ejection head  54 , there is less concern that defective ejection may occur in the liquid ejection apparatus  11 . For example, when the liquid ejection head  54  is erroneously replaced by the user with the liquid ejection head  54  that has previously been determined as having a problem related to ejection, the control section  70  can detect the fact. In this case, the control section  70  can prohibit the use of the liquid ejection apparatus  11 . 
     The control section  70  finishes the attachment check process for the liquid ejection head  54 . In this state, the liquid ejection apparatus  11  can perform recording on the medium M. Even in a case where the use of the liquid ejection apparatus  11  is prohibited, when the control section  70  determines that the attached liquid ejection head  54  can be used based on the model information written on the IC chip  56  and the ejection-related problem history, the control section  70  may cancel the prohibition of the use of the liquid ejection apparatus  11 . 
     As illustrated in  FIG.  9   , when the attachment check process for the new liquid ejection head  54  is finished, in a case where the control section  70  determines that a problem related to ejection has occurred in step S 401 , and a delivery request has not been transmitted in step S 407 , the control section  70  immediately starts the check flow. That is, when the power switch  25   a  is turned on by the user, in a case where the problem related to ejection has occurred but the delivery request has not been transmitted, the control section  70  can immediately start the check flow including the delivery request. 
     When the liquid ejection apparatus  11  performs recording on the medium M, the liquid L is ejected from the nozzle  54   a  of the liquid ejection head  54  toward the medium M. The liquid ejection apparatus  11  alternately repeats a transport operation in which the medium M is transported to the next recording position and a recording operation in which the liquid L is ejected from the nozzle  54   a  of the liquid ejection head  54  while the carriage unit  50  is being moved in the scanning direction X at the next recording position, and thus characters, images, or the like are recorded on the medium M. 
     The liquid ejection apparatus  11  performs recording on the medium M, and thus the operation of ejecting the liquid L from the nozzle  54   a  of the liquid ejection head  54  is repeated. As illustrated in  FIG.  4   , in the liquid ejection apparatus  11 , when recording is not performed, the cap portion  73  comes into contact with the liquid ejection head  54  to form the closed space CS surrounding the nozzles  54   a . However, the liquid L in the liquid ejection head  54  is always in contact with air at the opening of the nozzle  54   a , and thus water in the liquid L evaporates little by little. Thus, the liquid L in the portion that is always in contact with air at the opening of the nozzle  54   a  may be thickened. That is, the opening of the nozzle  54   a  may be clogged with the thickened liquid L, and thus defective ejection in which the liquid L is not ejected may occur. 
     As illustrated in  FIG.  8   , the monitoring section  55  constantly monitors whether or not defective ejection has occurred in the liquid ejection head  54 , and notifies the detector  70   a  of a monitoring result. Then, in step S 402  and step S 403  in  FIG.  9   , the control section  70  automatically maintains the liquid ejection head  54  with the maintenance section  71  according to the result of which the monitoring section  55  notifies the detector  70   a . The liquid L that has clogged the opening of the nozzle  54   a  due to thickening is discharged from the opening of the nozzle  54   a  through maintenance. Thus, it is possible to reduce concern that defective ejection may occur in printing after the automatic maintenance is executed. 
     When the detector  70   a  detects that the automatic maintenance has been repeatedly executed a predetermined number of times or more in step S 405  in  FIG.  9   , the control section  70  determines in step S 406  that a problem related to ejection has occurred. That is, the detector  70   a  detects that the automatic maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. Consequently, in a case where the detector  70   a  detects a problem and there is defective ejection that is not solved even when the automatic maintenance is repeatedly executed a predetermined number of times or more, the control section  70  determines that a problem related to ejection has occurred. Therefore, the control section  70  can start a check flow including a delivery request for a new replacement liquid ejection head. 
     In the liquid ejection head  54 , even when the state of defective ejection continues, there is a case where the automatic maintenance may not be repeatedly executed a predetermined number of times or more by the control section  70 . For example, when the residual vibration information of the liquid chamber is near a detection threshold value, even for the same defective ejection, there is a case where the defective ejection may or may not be detected, so that the automatic maintenance may not be repeatedly executed a predetermined number of times or more. In such a case, the user notices the defective ejection by checking a printing result of printed matter, and the manual maintenance that is maintenance performed by the user is executed. 
     When the detector  70   a  detects that the manual maintenance has been repeatedly executed a predetermined number of times or more in step S 410  in  FIG.  9   , the control section  70  determines in step S 406  that a problem related to ejection has occurred. That is, the detector  70   a  detects that the maintenance has been repeatedly executed by the user a predetermined number of times or more as a problem related to ejection. Consequently, in a case where there is defective ejection that is not solved even when the manual maintenance is repeatedly executed a predetermined number of times or more, the control section  70  determines that a problem related to ejection has occurred. Therefore, the control section  70  can start a check flow including a delivery request for a new replacement liquid ejection head. 
     The liquid ejection apparatus  11  includes the operation section  25  as an example of an input section to which the user can input the occurrence of a problem related to ejection. The user can input the occurrence of a problem related to ejection to the operation section  25  without waiting for the automatic maintenance to be repeatedly executed a predetermined number of times or more or the manual maintenance to be repeatedly executed a predetermined number of times or more. In step S 411  in  FIG.  9   , when the user inputs the occurrence of a problem related to ejection to the operation section  25 , the control section  70  determines that the problem related to ejection has occurred in step S 406 . Therefore, the control section  70  can start a check flow including a delivery request for a new replacement liquid ejection head. 
     The liquid ejection apparatus  11  includes the operation section  25  to which the user can input a delivery request for a new liquid ejection head. The user can input a delivery request for a new liquid ejection head to the operation section  25  without waiting for the automatic maintenance to be repeatedly executed a predetermined number of times or more or the manual maintenance to be repeatedly executed a predetermined number of times or more. When a delivery request is input to the operation section  25  in step S 412  in  FIG.  9   , the control section  70  determines that a problem related to ejection has occurred in step S 406 , and thus the control section  70  can start a check flow including a delivery request for a new replacement liquid ejection head. 
     When the control section  70  determines in step S 406  in  FIG.  9    that the problem related to ejection has occurred in the liquid ejection apparatus  11 , the control section  70  starts the check flow illustrated in  FIG.  10   . 
     As illustrated in  FIG.  10   , in steps S 501  to S 503 , in a case where the occurrence of a problem related to ejection or a delivery request is input to the operation section  25 , the control section  70  starts to execute the automatic maintenance in step S 511  when the manual maintenance has not been repeatedly executed a predetermined number of times or more. In other words, when the manual maintenance is not repeatedly executed a predetermined number of times or more immediately before the occurrence of the problem related to ejection or the delivery request is input, the automatic maintenance is executed. That is, when the user inputs the occurrence of the problem related to ejection or the delivery request to the operation section  25  as an example of an input section, the control section  70  causes the maintenance section  71  to execute the maintenance one or more times. Consequently, when a recovery from the problem is made through the maintenance, it is not necessary for the control section  70  to start the check flow including the delivery request for a new replacement liquid ejection head. 
     In a case where the user inputs the occurrence of the problem related to ejection or the delivery request, when the manual maintenance has already been repeatedly executed a predetermined number of times or more, the problem cannot be solved through the maintenance, and thus the control section  70  can immediately start a check flow including the delivery request for a new replacement liquid ejection head. 
     That is, when the user inputs the occurrence of the problem related to ejection or the delivery request, the control section  70  can execute a check flow in a case where a maintenance execution status before the input or a status of a result of executing automatic maintenance after the input. 
     The control section  70  starts the check flow in step S 503 , and checks the user&#39;s selection of the delivery request for the new liquid ejection head and transmits the delivery request for the new liquid ejection head to the server apparatus  80  in steps S 504  and S 505 . The control section  70  prohibits the use of the liquid ejection apparatus  11 . Consequently, it is possible to prevent printing from being continued in the liquid ejection head  54  having a problem related to ejection. 
     In steps S 506  and S 507 , the control section  70  checks whether the user has selected a delivery request for new liquid storage bodies for all the liquid storage bodies  28 , and transmits the delivery request for all new liquid storage bodies to the server apparatus  80  when the delivery request for the new liquid storage bodies for all the liquid storage bodies  28  has been selected. In a case where the delivery request for the new liquid storage bodies for all the liquid storage bodies  28  has not been selected, in steps S 509  and S 510 , when there is the liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the liquid storage bodies  28 , the control section  70  transmits a delivery request for a new liquid storage body corresponding to the liquid storage body  28  of which the residual amount is less than the predetermined threshold value to the server apparatus  80 . 
     Consequently, the user can request delivery of both the liquid ejection head  54  and the liquid L, which may be a cause of the problem related to ejection, and the user can also request delivery of a new liquid storage body in accordance with a delivery timing of a new liquid ejection head. 
     As illustrated in  FIG.  8   , the liquid ejection apparatus  11  includes the liquid ejection head  54  that is detachably attached and ejects the liquid L, and the control section  70  that can transmit a delivery request for a new liquid ejection head to the server apparatus  80  via the network NW. Consequently, the user can request delivery of a new replacement liquid ejection head when needed. 
     The liquid ejection apparatus  11  further includes the detector  70   a  detecting a problem related to ejection. Consequently, the user can request delivery of a new replacement liquid ejection head when a problem related to ejection has occurred. 
     In the liquid ejection apparatus  11  illustrated in  FIG.  8   , the control section  70  can automatically transmit a delivery request when the detector  70   a  detects a problem. Consequently, the user can save the time and effort to request delivery. 
     As illustrated in  FIG.  8   , the delivery system  100  for the liquid ejection apparatus includes the liquid ejection apparatus  11  and the server apparatus  80  having the reception section  80   a  receiving a delivery request for a new liquid ejection head transmitted from the control section  70 . Consequently, the user can replace the liquid ejection head with a new liquid ejection head  54  when a problem has occurred in the liquid ejection head  54 . 
     In step S 505  illustrated in  FIG.  10   , the control section  70  prohibits the use of the liquid ejection apparatus  11  after transmitting the delivery request for the new liquid ejection head to the server apparatus  80 . Consequently, it is possible to prevent printing from being continued by the defective liquid ejection head  54 , but downtime of the liquid ejection apparatus  11  has occurred until the new liquid ejection head  54  is delivered. However, even when the liquid ejection head  54  has a problem related to ejection, the user may want to print printed matter. In the present embodiment, on condition of a request from the user, the control section  70  cancels the prohibition of the use of the liquid ejection apparatus  11  after transmitting the delivery request for the new liquid ejection head. Consequently, even when the liquid ejection head  54  has a problem related to ejection, printing can be continued until a new liquid ejection head  54  arrives, depending on the user&#39;s request. 
     When the new liquid ejection head  54  is delivered to the user, the user starts work of replacing the liquid ejection head  54  having the problem with the delivered new liquid ejection head  54 . 
     First, the user causes the control section  70  to execute an operation of removing a liquid in the liquid ejection head  54  before the liquid ejection head  54  having the problem and attached to the liquid ejection apparatus  11  is detached from the liquid ejection apparatus  11 . For example, the user operates the operation section  25  to cause the control section  70  to display the liquid ejection head replacement flow on the display section  26 . The user presses a button on the operation section  25  for which an instruction is given on the display section  26  as a button for starting the liquid removal operation, and thus causes the control section  70  to execute the liquid removal operation illustrated in  FIG.  5   . That is, the control section  70  starts the liquid ejection head replacement flow that is a flow for detaching the attached liquid ejection head  54  having the problem from the liquid ejection apparatus  11  and attaching the delivered new liquid ejection head  54 , and first allows the user to press the button for executing the liquid removal operation. 
     As illustrated in  FIG.  5   , the liquid removal operation that is first performed in the liquid ejection head replacement flow includes a step of closing the supply flow path through which the liquid L is supplied to the liquid ejection head  54  with the opening/closing mechanism. In the present embodiment, this step is a closing step of closing the first liquid supply flow path  75  with the first opening/closing valve  75   b . In step S 102 , the control section  70  executes this step. It is possible to suppress leakage of the liquid L when the liquid ejection head  54  having a problem and attached to the liquid ejection apparatus  11  is detached from the liquid ejection apparatus  11  by closing the supply flow path through which the liquid Lis supplied to the liquid ejection head  54 . 
     When the control section  70  finishes the liquid removal operation illustrated in  FIG.  5   , the user detaches the liquid ejection head  54  having a problem and attached to the liquid ejection apparatus  11  from the liquid ejection apparatus  11 , and executes work of attaching the delivered new liquid ejection head  54  to the liquid ejection apparatus  11 . For example, the control section  70  displays, on the display section  26 , a state in which the liquid removal operation illustrated in  FIG.  5    has been finished, and displays a message for prompting the user of perform work of detaching the attached liquid ejection head  54  having a problem from the liquid ejection apparatus  11  and attaching the delivered new liquid ejection head  54  on the display section  26 . 
     The user exposes the carriage unit  50  by opening the upper cover  13  illustrated in  FIG.  1   . Since the carriage unit  50  is located at the home position HP illustrated in  FIG.  2    during non-recording in which recording is not performed on the medium M, the user can access the liquid ejection head  54  illustrated in  FIG.  3    mounted on the carriage unit  50  when the upper cover  13  is opened. The user executes the work of detaching the liquid ejection head  54  from the carriage unit  50  and the work of attaching the delivered new liquid ejection head  54 , closes the upper cover  13 , and finishes the work of replacing the liquid ejection head  54 . That is, the user can perform the detachment work and the attachment work for the liquid ejection head  54  without detaching the casing  12  from the liquid ejection apparatus  11 . 
     In the present embodiment, in step S 107  corresponding to the liquid removal operation illustrated in  FIG.  5   , the control section  70  moves the cap portion  73  to the retreat position away from the liquid ejection head  54  in the −Z direction. Consequently, the user can detach the liquid ejection head  54  in a state in which the cap portion  73  does not come into contact with the liquid ejection head  54 . 
     When the delivered new liquid ejection head  54  is attached to the liquid ejection apparatus  11  by the user and the control section  70  checks that the upper cover  13  has been closed by a cover opening/closing sensor (not illustrated), the control section  70  executes the “ejection-related problem determination process” illustrated in  FIG.  9   . As described above, the present routine is executed at a timing immediately after power of the liquid ejection apparatus  11  is turned on by operating the power switch  25   a  and an initialization operation for the liquid ejection apparatus  11  is performed, or is executed at a timing at which the liquid ejection head  54  is attached to the carriage unit  50  in a state in which the power is turned on. 
     As the first process in the “ejection-related problem determination process” illustrated in  FIG.  9   , the control section  70  executes the “new liquid ejection head attachment check process” illustrated in  FIG.  11   . When the delivered new liquid ejection head  54  is attached, the ejection-related problem history is reset, the ejection-related problem flag is initialized, the message displayed on the display section  26  is deleted, and, when the use of the liquid ejection apparatus  11  is prohibited, the prohibition is canceled. The control section  70  executes the determination processes in steps S 402 , S 408 , S 411 , and S 412  in  FIG.  9    in parallel. That is, the liquid ejection apparatus  11  is in a state in which monitoring of defective ejection using the monitoring section  55  and detection of the user&#39;s operation on the operation section  25  are executed in parallel. 
     When the user finishes the replacement work for the new liquid ejection head, the user presses a button on the operation section  25  for which an instruction is given on the display section  26  as a button for finishing the replacement work, and thus notifies the control section  70  of finishing of the replacement work. When a delivery request for a new liquid storage body is transmitted in addition to a delivery request for a new liquid ejection head, the user performs replacement with both the new liquid ejection head  54  and the new liquid storage body  28 , and then the user presses the button for finishing the replacement work, and thus notifies the control section  70  of finishing of the replacement work. Consequently, both the liquid ejection head  54  and the liquid L that may be a cause of a problem related to ejection can be replaced. 
     When the control section  70  is notified of finishing of the replacement work through the user&#39;s operation, the control section  70  executes the liquid filling operation illustrated in  FIG.  6   . In the present embodiment, in step S 201  corresponding to the liquid filling operation illustrated in  FIG.  6   , the control section  70  moves the cap portion  73  at the retreat position to the contact position illustrated in  FIG.  4   . Consequently, the liquid ejection head  54  can be capped by the cap portion  73  as soon as the liquid ejection head  54  is attached. 
     Following the liquid filling operation, the control section  70  automatically executes a maintenance step of performing maintenance with the maintenance section  71 . Finally, the control section  70  displays, on the display section  26 , a state in which the liquid ejection head replacement flow displayed on the display section  26  has been finished, and finishes the liquid ejection head replacement flow. Consequently, the user can start printing immediately after the liquid ejection head replacement flow. 
     As described above, when the liquid ejection head replacement flow is finished, the liquid ejection apparatus  11  executes monitoring of defective ejection of the new liquid ejection head  54  after the replacement using the monitoring section  55  and detection of the user&#39;s operation on the operation section  25  after the replacement in parallel, by using the control section  70 . Thus, even when a problem related to ejection has occurred again in the liquid ejection apparatus  11 , the user can request delivery of a new replacement liquid ejection head. 
     The effects of the present embodiment will be described. 
     (1) The liquid ejection apparatus  11  includes the liquid ejection head  54  that is detachably attached and ejects the liquid L, and the control section  70  that can transmit a delivery request for a new liquid ejection head to the server apparatus  80  via the network NW. Thus, a user can request delivery of a new replacement liquid ejection head when needed. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (2) The liquid ejection apparatus  11  further includes the detector  70   a  detecting a problem related to ejection. Thus, it is possible to request delivery of a new replacement liquid ejection head when a problem related to ejection has occurred. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (3) The control section  70  automatically transmits a delivery request when the detector  70   a  detects a problem related to ejection. Thus, it is possible to save the user&#39;s time and effort to request delivery. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (4) When the detector  70   a  detects a problem related to ejection, the control section  70  starts a check flow including a delivery request for a new liquid ejection head. Thus, when a problem has occurred in the liquid ejection head  54 , it is possible to request delivery of a new replacement liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (5) The detector  70   a  detects that automatic maintenance has been repeatedly executed a predetermined number of times or more as a problem related to ejection. Thus, when there is defective ejection that is not solved even when the automatic maintenance has been repeatedly executed a predetermined number of times or more, it is possible to request delivery of a new replacement liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (6) The detector  70   a  detects that maintenance has been repeatedly executed a predetermined number of times or more by the user as a problem related to ejection. Thus, in a case where a problem that is not solved has occurred even when the maintenance has been repeatedly executed a predetermined number of times or more by the user, it is possible to request delivery of a new replacement liquid ejection head. Even when a problem that is not detected by the monitoring section  55  has occurred in the liquid ejection head  54 , the detector  70   a  determines that a problem related to ejection has occurred, and can thus request delivery of a new replacement liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (7) The liquid ejection apparatus  11  further includes the operation section  25  as an example of an input section to which the user can input the occurrence of a problem related to ejection. Thus, when the user determines that the liquid ejection head  54  has a problem, the liquid ejection apparatus  11  can take appropriate measures. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (8) When the user inputs the occurrence of a problem related to ejection to the operation section  25  as an example of an input section, the control section  70  causes the maintenance section  71  to perform the maintenance one or more times. Thus, when the user inputs the occurrence of a problem related to ejection, it is possible to recheck whether or not a recovery from the problem can be made through the maintenance. Consequently, when a recovery from the problem is made through the maintenance, since the user can continue to use the attached liquid ejection head  54 , in the liquid ejection apparatus  11 , it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand. 
     (9) When the user inputs the occurrence of a problem related to ejection to the operation section  25  as an example of an input section, the control section  70  starts a check flow including a delivery request for a new liquid ejection head. Thus, when the user inputs the occurrence of a problem related to ejection, it is possible to take measures according to a status at that time. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (10) The control section  70  starts a check flow according to an execution status of maintenance before the input is performed by the operation section  25  as an example of an input section. Thus, when the user inputs the occurrence of a problem related to ejection, it is possible to take measures according to the execution status of the maintenance before that. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (11) The control section  70  prohibits the use of the liquid ejection apparatus  11  when a delivery request for a new liquid ejection head is transmitted. Consequently, in the liquid ejection apparatus  11 , it is possible to prevent printing from being continued in the liquid ejection head  54  having a problem related to ejection. 
     (12) On condition of a request from the user, the control section  70  cancels the prohibition of the use of the liquid ejection apparatus  11  after transmitting a delivery request for a new liquid ejection head. Thus, even when the liquid ejection head  54  has a problem, printing can be continued until a new liquid ejection head  54  arrives, depending on the user&#39;s request. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (13) The control section  70  can carry out a liquid ejection head replacement flow that is a flow for attaching the delivered new liquid ejection head  54 , and the liquid ejection head replacement flow includes a maintenance step of performing maintenance with the maintenance section  71 . Thus, printing can be started immediately after the liquid ejection head replacement flow. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     (14) The liquid ejection apparatus  11  includes the first liquid supply flow path  75  as an example of a supply flow path through which the liquid L is supplied from the liquid storage body  28  to the liquid ejection head  54 , and the first opening/closing valve  75   b  as an example of an opening/closing mechanism opens and closes the first liquid supply flow path  75 , and the liquid ejection head replacement flow includes a closing step of closing the first liquid supply flow path  75  with the first opening/closing valve  75   b . Consequently, in the liquid ejection apparatus  11 , it is possible to suppress liquid leakage when the liquid ejection head  54  is replaced. 
     (15) The liquid ejection head  54  is configured to eject the liquid L stored in the liquid storage body  28 , and the control section  70  can transmit a delivery request for a new liquid storage body in addition to a delivery request for a new liquid ejection head when the detector  70   a  detects a problem related to the ejection. Thus, it is possible to request delivery of both the liquid ejection head  54  and the liquid L that may be a cause of the problem related to ejection. 
     (16) When a delivery request for a new liquid ejection head is made, in a case where there is a liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the plurality of liquid storage bodies  28  storing the liquids L to be supplied to the liquid ejection head  54 , the control section  70  transmits a delivery request for a new liquid storage body in addition to a delivery request for a new liquid ejection head. Consequently, it is possible to request delivery of a new liquid storage body corresponding to a liquid storage body having a small residual amount in accordance with a delivery timing of the new liquid ejection head. 
     (17) The delivery system  100  for the liquid ejection apparatus  11  includes the liquid ejection apparatus  11  and the server apparatus  80  having the reception section  80   a  receiving a delivery request for a new liquid ejection head transmitted from the control section  70 . Thus, when a problem has occurred in the liquid ejection head  54 , the liquid ejection head  54  can be replaced with a new liquid ejection head  54 . Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 . 
     Second Embodiment 
     Hereinafter, a liquid ejection apparatus  11  according to a second embodiment will be described with reference to the drawings. In the first embodiment, a user replaces the liquid storage body  28 . The second embodiment is different from the first embodiment in that the liquid storage body  28  is fixed to the liquid ejection apparatus  11 , and the user replenishes the liquid storage body  28  with a liquid such as ink from a refill container through a supply port of the liquid storage body  28 . The second embodiment is substantially the same as the first embodiment except for the above content, and thus an overlapping description will not be repeated by giving the same reference numeral to the same constituent. 
     Configuration of Liquid Ejection Apparatus 
     As illustrated in  FIG.  1   , the liquid supply unit  27  has the lid portion  27   b  that can be opened and closed upward. The plurality of liquid storage bodies  28  accommodated in the liquid supply unit  27  have supply ports (not illustrated) through which replenishment with the liquid L can be performed thereon. When the user opens the lid portion  27   b , the supply port is exposed. For example, the liquid ejection apparatus  11  has a configuration in which, when the user looks at the window portions  27   a  and liquid amounts decrease, the user opens the lid portion  27   b  and replenishes the liquid storage bodies  28  with liquids such as ink from a plurality of refill containers (not illustrated) through the supply ports. The plurality of refill containers are, for example, ink bottles storing inks with different colors such as black, cyan, magenta, and yellow. The liquid ejection head  54  is configured to eject the liquid L stored in the liquid storage body  28  that can be replenished with the liquid L in the refill container. 
     Configuration of Delivery System 
     As illustrated in  FIG.  8   , the delivery system  100  delivers a replacement liquid ejection head  54  replacing the liquid ejection head  54  that needs to be replaced in the liquid ejection apparatus  11 , to a user using the liquid ejection apparatus  11 . In this case, the control section  70  may transmit a delivery request for a new replenishment refill container to the transmission section  60  via the network NW. That is, the server apparatus  80  may prepare for delivery of the new refill container when receiving a request signal for the delivery of the new replenishment refill container transmitted from the liquid ejection apparatus  11 . 
     Even when the control section  70  does not detect a problem related to ejection, the delivery system  100  may deliver the replacement liquid ejection head  54  to the user using the liquid ejection apparatus  11  in response to the user&#39;s instruction from the operation section  25 . The delivery system  100  may deliver the new replenishment refill container to the user using the liquid ejection apparatus  11  in response to the user&#39;s instruction from the operation section  25 . 
     Check Flow 
     In the present embodiment, when there is a liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the liquid storage bodies  28 , the control section  70  transmits a delivery request for a new refill container to the server apparatus  80  with respect to the liquid storage body  28  of which residual amount is less than the predetermined threshold value. 
     With reference to a flowchart of  FIG.  12   , only steps in which the process performed by the control section  70  is different from that in the first embodiment will be described with respect to the subroutine of the check flow. 
     In step S 506   a , the control section  70  displays, on the display section  26 , a check screen regarding whether or not a new refill container for the liquid storage body  28  of the liquid ejection apparatus  11  is to be delivered. For example, the control section  70  displays, on the display section  26 , a message including “do you request delivery of new refill containers for all liquid storage bodies along with delivery of a new liquid ejection head?”, and requests the user to select and input “YES” or “NO” by using the operation section  25 . The control section  70  determines whether or not a delivery request for new refill containers for all the liquid storage bodies  28  has been selected by using the operation section  25 . When the delivery request for new refill containers for all the liquid storage bodies  28  has been selected, a determination result in step S 506   a  is YES, and the process proceeds to step S 507   a . When the delivery request for new refill containers for all the liquid storage bodies  28  has not been selected, the determination result in step S 506   a  is NO, and the process proceeds to step S 509 . The control section  70  may proceed to step S 509  after executing step S 505  without performing the process in step S 506   a.    
     There is a case where nozzle check printing may be executed in the liquid ejection apparatus  11 , and the user may check a result of the nozzle check printing to determine which liquid storage body  28  a problem has occurred in a nozzle ejecting a liquid supplied from. For example, when defective ejection has occurred in the yellow ink, there may be a problem with the yellow ink. In this case, it is desirable that a new refill container for the liquid storage body  28  storing the yellow ink in which the defective ejection has occurred is delivered. That is, in step S 506   a , the control section  70  may display, on the display section  26 , a screen for selecting which new refill container is to be delivered among the liquid storage bodies  28  of the liquid ejection apparatus  11 , and the control section  70  may allow the user to select which new refill container is to be delivered. 
     In step S 507   a , as illustrated in  FIG.  8   , the control section  70  causes the transmission section  60  to transmit a delivery request for a new refill container for the liquid storage body  28  to the server apparatus  80  via the network NW. When the detector  70   a  detects a problem related to ejection, the control section  70  may transmit a delivery request for a new refill container in addition to a delivery request for a new liquid ejection head. The server apparatus  80  receives the transmission content from the transmission section  60  by using the reception section  80   a , and receives the delivery request for the new refill container for the liquid storage body  28 . 
     As in the present embodiment, the control section  70  may transmit a delivery request for new refill containers for all the liquid storage bodies  28  to the server apparatus  80 , or may transmit a delivery request for only a new refill container for the liquid storage body  28  selected by the user to the server apparatus  80 . 
     In step S 508 , the control section  70  finishes the delivery flow. For example, when delivery of the new liquid ejection head  54  and the new refill containers for all the liquid storage bodies  28  has been requested, the control section  70  displays, on the display section  26 , a message including “delivery of the new liquid ejection head and the new refill containers for all the liquid storage bodies has been requested”, and finishes the delivery flow. The control section  70  finishes the subroutine of the check flow. 
     In step S 509 , the control section  70  determines whether or not there is the liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the liquid storage bodies  28  included in the liquid ejection apparatus  11 . For example, the liquid ejection apparatus  11  has a plurality of liquid residual amount sensors (not illustrated) each detecting a residual amount of the liquid L in each liquid storage body  28  in the liquid supply unit  27 , and the liquid residual amount sensor including a light projecting element and a light receiving element detects a residual amount of the liquid L based on an intensity of reflected light that changes according to the residual amount of the liquid L stored in each liquid storage body  28 . The control section  70  determines whether or not there is a liquid storage body  28  of which a residual amount of the liquid L stored in the liquid storage body  28  is less than a predetermined threshold value based on a signal that is input from the liquid residual amount sensor. For example, the threshold value is a value determined based on the number of days until the liquid storage body  28  arrives and an amount of the liquid L consumed in the liquid ejection apparatus  11  in a day. When there is the liquid storage body  28  of which the residual amount is less than the predetermined threshold value, a determination result in step S 509  is YES, and the process proceeds to step S 510   a . When there is no liquid storage body  28  of which the residual amount is less than the predetermined threshold value, the determination result in step S 509  is NO, and the process proceeds to step S 508 . 
     In step S 510   a , the control section  70  causes the transmission section  60  to transmit a delivery request for a new refill container for the liquid storage body  28  of which the residual amount is less than a predetermined threshold value to the server apparatus  80  via the network NW. When the detector  70   a  detects a problem, the control section  70  may transmit a delivery request for a new refill container corresponding to the liquid storage body  28  of which the residual amount is less than the predetermined threshold value, in addition to the delivery request for the new liquid ejection head. That is, when a delivery request for a new liquid ejection head is made, in a case where there is a liquid storage body  28  of which the residual amount is less than the predetermined threshold value among the plurality of liquid storage bodies  28  storing the liquids L to be supplied to the liquid ejection head  54 , the control section  70  transmits the delivery request for the new refill container in addition to the delivery request for the new liquid ejection head. The server apparatus  80  receives the transmission content from the transmission section  60  by using the reception section  80   a , and receives the delivery request for the new refill container. 
     When the user has already requested the delivery of the new refill container, the delivery request for the new refill container does not need to be made. When there are a plurality of liquid storage bodies  28  in which residual amounts are less than the predetermined threshold value, the control section  70  may automatically a delivery request for new refill containers corresponding to the plurality of liquid storage bodies  28  to the server apparatus  80 . 
     In step S 508 , the control section  70  finishes the delivery flow. For example, when a new liquid ejection head  54  and a new refill container for the yellow ink are requested to be delivered, the control section  70  displays, on the display section  26 , a message including “delivery of a new liquid ejection head and a new refill container for the yellow ink has been requested”, and finishes the delivery flow. The control section  70  finishes the subroutine of the check flow. 
     An operation of the present embodiment will be described. 
     Also in the operation of the second embodiment, the description overlapping with the operation of the first embodiment will not be repeated. 
     As illustrated in  FIG.  12   , in steps S 506   a  and S 507   a , the control section  70  checks whether the user has selected a delivery request for all new refill containers, and transmits the delivery request for the new refill containers to the server apparatus  80  when the delivery request for the new refill containers for all the liquid storage bodies  28  has been selected. When the delivery request for the new refill container for all the liquid storage bodies  28  has not been selected, in steps S 509  and S 510   a , when there is the liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the liquid storage bodies  28 , the control section  70  transmits a delivery request for a new refill container corresponding to the liquid storage body  28  of which the residual amount is less than the predetermined threshold value to the server apparatus  80 . 
     Consequently, the user can request delivery of both the liquid ejection head  54  and the liquid L, which may be a cause of the problem related to ejection, and the user can also request delivery of a new refill container in accordance with a delivery timing of a new liquid ejection head. 
     When the user finishes the replacement work for the new liquid ejection head, the user presses a button on the operation section  25  for which an instruction is given on the display section  26  as a button for finishing the replacement work, and thus notifies the control section  70  of finishing of the replacement work. When a delivery request for a new refill container is transmitted in addition to a delivery request for a new liquid ejection head, the user performs replacement work for the new liquid ejection head and work of pouring a liquid from the new refill container into the liquid storage body  28 . Thereafter, the user presses the button for finishing the replacement work, and thus notifies the control section  70  of finishing of the replacement work. Consequently, the user can replace both the liquid ejection head  54  and the liquid L that may be a cause of a problem related to ejection. 
     The effects of the present embodiment will be described. 
     In the liquid ejection apparatus  11 , the same effects as (1) to (14) in the first embodiment can be achieved. 
     (15) The liquid ejection head  54  is configured to eject the liquid L stored in the liquid storage body  28 , and the control section  70  can transmit a delivery request for a new refill container in addition to a delivery request for a new liquid ejection head when the detector  70   a  detects a problem related to the ejection. Consequently, when a problem has occurred in the liquid ejection head  54  in the liquid ejection apparatus  11 , it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head  54  at the user&#39;s hand and also to request delivery of both the liquid ejection head  54  and the liquid L that may be a cause of the problem related to ejection. 
     (16) When a delivery request for a new liquid ejection head is made, in a case where there is a liquid storage body  28  of which a residual amount is less than a predetermined threshold value among the plurality of liquid storage bodies  28  storing the liquids L to be supplied to the liquid ejection head  54 , the control section  70  transmits a delivery request for a new refill container in addition to a delivery request for a new liquid ejection head. Consequently, it is possible to request delivery of a new refill container corresponding to a liquid storage body having a small residual amount in accordance with a delivery timing of the new liquid ejection head. 
     In the delivery system  100  for the liquid ejection head, the same effect as (17) in the first embodiment can be achieved. 
     The present embodiment may be modified and implemented as follows. The present embodiment and the following modification examples may be implemented in combination with each other within a technically consistent scope.
         The liquid ejection apparatus  11  is not limited to the off-carriage type as in the present embodiment in which the replaceable liquid storage body  28  is provided in a location different from the carriage unit  50 , and may be of the on-carriage type in which the replaceable liquid storage body  28  is provided in the carriage unit  50 . When the liquid ejection apparatus  11  is of the on-carriage type, the liquid ejection head  54  may be replaced without providing the first opening/closing valve  75   b , the first atmosphere communication path  76 , and the first atmosphere opening valve  76   a . Even when the liquid ejection apparatus  11  is of the off-carriage type, the first atmosphere communication path  76  and the first atmosphere opening valve  76   a  does not need to be provided, and the first opening/closing valve  75   b  may be replaced with a pressure regulating valve that is opened when a downstream thereof has a predetermined negative pressure.   When the liquid ejection apparatus  11  is of the off-carriage type as in the present embodiment, the liquid ejection head  54  may configure a head unit integrally with a reservoir that reserves the liquid L supplied to the liquid ejection head  54 . Even when the liquid ejection apparatus  11  is of the on-carriage type, the liquid ejection head  54  may configure a head unit integrally with a reservoir that reserves the liquid L supplied to the liquid ejection head  54  in order to continuously supply the liquid from the liquid storage body  28  to the liquid ejection head  54 . When the head unit is configured integrally with the reservoir, delivery is performed in units of the head unit. In this case, a new liquid ejection head unit of which a reservoir is filled with the liquid L may be delivered. The new liquid ejection head unit to be delivered is already filled with the liquid L. Thus, it is not necessary to perform an operation of filling the liquid ejection head  54  with a liquid after the liquid ejection head unit is replaced. A user can use the liquid ejection apparatus  11  immediately after replacing the liquid ejection head unit.   The liquid storage body  28  may be provided outside the casing  12 .   Although there are four types of liquids L used in the liquid ejection apparatus  11  of the present embodiment, any number of liquids L may be used in the liquid ejection apparatus  11 . The liquid L used in the liquid ejection apparatus  11  may be one type.   In the present embodiment, the liquid ejection head  54  has the monitoring section  55 , but the monitoring section  55  may be provided in a location other than the liquid ejection head  54 . In the present embodiment, in order to employ a method of acquiring residual vibration information of the liquid chamber in the liquid ejection head  54  and determining whether or not ejection is normal, the liquid ejection head  54  has a monitoring section  55 . However, when the liquid ejection apparatus  11  employs another monitoring method, it is desirable that the monitoring section  55  is provided in a location suitable for the monitoring method.   In the present embodiment, the automatic maintenance is executed in accordance with a result of which a notification is sent from the monitoring section  55  after one print job is finished, but, when one print job is finished, the control section  70  may display a message on the display section  26  and allow a user to perform the manual maintenance by using the operation section  25  in accordance with a result of which a notification is sent from the monitoring section  55 .   In the present embodiment, after one print job is finished, the automatic maintenance is executed in accordance with a result of which a notification is sent from the monitoring section  55 , but the automatic maintenance may be executed in accordance with a result of which a notification is sent from the monitoring section  55  every time one page of one print job is printed. In this case, when the detector  70   a  detects that an operation of performing the automatic maintenance after finishing of printing of one page of one print job has been repeatedly executed a plurality of times, it may be determined that a problem related to ejection has occurred.   Even when maintenance has not been repeatedly executed a predetermined number of times or more, in a case where the detector  70   a  detects that an operation of performing maintenance within a predetermined period has been executed a predetermined number of times or more, the detector  70   a  may determine that a problem related to ejection has occurred. Even when the maintenance has not been repeatedly executed a predetermined number of times or more, in a case where the maintenance has been performed a predetermined number of times or more most recently, there is a high probability that the liquid ejection head  54  may have a problem. For example, when the detector  70   a  detects that an operation of performing maintenance during 24 hours has been executed a predetermined number of times or more, the detector  70   a  may determine that a problem related to ejection has occurred.   The above predetermined period does not need to be time. For example, the predetermined period may be a period from when the power switch  25   a  is turned on until the power switch  25   a  is turned off. When the detector  70   a  detects that an operation of executing maintenance has been executed a predetermined number of times or more within the most recently printed predetermined number of sheets, the detector  70   a  may determine that a problem related to ejection has occurred.   The liquid ejection head  54  does not need to include the IC chip  56  or a storage section in place of the IC chip  56 . In this case, the ejection-related problem history information is stored only in the memory of the control section  70 . In a case where the liquid ejection head replacement flow is executed, the control section  70  unconditionally may determine that the new liquid ejection head  54  is attached when the liquid ejection head  54  is attached, reset the ejection-related problem history information stored in the memory of the control section  70 , and initialize the ejection-related problem flag.   The IC chip  56  included in the liquid ejection head  54  may be an IC chip that can only be read. In this case, only the model information is stored in the IC chip  56 . Based on the model information, the control section  70  can determine whether or not the liquid ejection head  54  is a new liquid ejection head  54  when the liquid ejection head  54  is attached.   The ejection-related problem history information does not need to be stored in the memory of the IC chip  56  or the control section  70 . It may be determined whether or not a problem related to ejection is determined as having occurred depending on whether or not the automatic maintenance or the manual maintenance is performed immediately before the problem related to ejection occurs. There may be a configuration in which the number of times of the automatic maintenance or the manual maintenance is stored only in the memory of the control section  70 , and the number of times of the automatic maintenance or the manual maintenance is reset when the power switch  25   a  is turned off.   The ejection-related problem history information stored in the IC chip  56  may be only information regarding the presence or absence of the occurrence of a problem related to ejection. For example, “zero” is written in the ejection-related problem history information of the new liquid ejection head  54 , and, when the detector  70   a  detects a problem related to ejection, the control section  70  may rewrite “zero” in the ejection-related problem history information in the IC chip  56  of the attached liquid ejection head  54  to 1. In step S 606  in  FIG.  11   , the control section  70  may determine whether or not the liquid ejection head  54  has a problem related to ejection based on the ejection-related problem history information in the IC chip  56 .   The ejection-related problem history information may include other information. For example, the ejection-related problem history information may include the number of times of inputting the occurrence of a problem related to ejection. When the number of times of inputting the occurrence of a problem related to ejection exceeds a specified number of times, the liquid ejection apparatus  11  may not accept cancellation of prohibition of use.   The maintenance history information stored in the IC chip  56  or the memory of the control section  70  as the ejection-related problem history information may include information regarding the date and time at which the maintenance was performed or information regarding the number of printed sheets after the liquid ejection head  54  was used when the maintenance was performed.   In a case where a user has input the occurrence of a problem related to ejection or a delivery request for a new liquid ejection head, when maintenance has not been performed before the input, the control section  70  may automatically perform the maintenance flow, and allow the user to select “recovered” or “not recovered” at the end of the maintenance flow. That is, in step S 502  in  FIG.  10   , the control section  70  may check whether or not maintenance has been performed before the input, and proceed to step S 511  when the determination result is NO. When “not recovered” is selected in step S 514 , the control section  70  may proceed to the delivery flow in step S 503 .   In a case where a user has input the occurrence of a problem related to ejection or a delivery request for a new liquid ejection head, when maintenance has not been performed before the input, the process may proceed to the maintenance flow in the check flow. That is, in step S 502  in  FIG.  10   , the control section  70  checks whether or not maintenance has been performed before the input, and, when the determination result is NO, in step S 511 , the control section  70  may start the maintenance flow as manual maintenance. When the maintenance flow is executed to the end, “recovered” or “not recovered” may be selected. When “not recovered” is selected, the control section  70  may proceed to the delivery flow in step S 503 .   In a case where a user has input the occurrence of a problem related to ejection or a delivery request for a new liquid ejection head, the control section  70  may check, with the user, whether or not maintenance has been performed, proceed to the maintenance flow when the maintenance has not been performed, and allow the user to select “recovered” or “not recovered” at the end of the maintenance flow. When “not recovered” is selected, the control section  70  may proceed to the delivery flow. The control section  70  may set step S 502  in  FIG.  10    as a step of checking, with the user, whether or not maintenance has been performed before the input. This maintenance may be automatic maintenance or manual maintenance.   When the new liquid ejection head  54  is delivered, the liquid storage body  28  for initial filling or a refill container may be delivered together.   After a delivery request for a new liquid ejection head is made, the control section  70  may give a notification for prompting replacement with the new liquid ejection head until the replacement of the liquid ejection head  54  is completed.   After a delivery request for a new liquid ejection head is made, the control section  70  may give a notification for prompting replacement with the new liquid ejection head only when some operation is performed by the user by using the operation section  25 .   The liquid ejection apparatus  11  or the server apparatus  80  may store a period from detection of a problem in the liquid ejection head  54  to replacement with the new liquid ejection head  54 . Since correct printing cannot be performed during this period, services such as refunds, gifts, and plan content changes corresponding to the stored period may be returned to the user.   Even in a case where a problem in the liquid ejection head  54  is detected, when the user does not select to perform replacement with a new liquid ejection head, services such as refunds, gifts, and plan content changes corresponding to the same may be returned to the user.   For recycling of the liquid ejection head  54 , a system for collecting the replaced old liquid ejection head  54  may be built. For example, the user puts the old liquid ejection head  54  in a box in which the new liquid ejection head  54  was packed and returns the box. For example, when a collection box for the old liquid ejection head  54  is pre-delivered to the user, the user puts the old liquid ejection head  54  in the box in advance, and the new liquid ejection head  54  is delivered, a delivery trader collects the box. For example, the user takes the old liquid ejection head  54  to a nearest consumer electronics retail store.   A specified number of times of maintenance performed by the user, for immediately proceeding to the delivery flow, may differ when the occurrence of a problem related to ejection is input to the input section and when a delivery request is input to the input section.   A predetermined threshold value for a residual amount of the liquid storage body  28  may differ for each user or for each liquid ejection apparatus used by the user depending on the number of days until a new liquid storage body  28  or a new refill container arrives at the user, the frequency with which the liquid Lis used in the liquid ejection apparatus  11 , and the like. When the liquid ejection apparatus  11  includes a plurality of types of liquid storage bodies  28 , the predetermined threshold value may differ for each liquid storage body  28 .   When the user has requested delivery, the control section  70  may proceed to the delivery flow regardless of the number of times of maintenance. That is, the control section  70  may immediately proceed to the delivery flow without performing automatic maintenance.   When the user determines that a recovery from the problem related to ejection has been made a little from the results of the automatic maintenance and the nozzle check printing in steps S 511  to S 513  in  FIG.  12   , a flow is configured such that the user causes the control section  70  to perform the automatic maintenance again. A recovery from defective ejection may be made through a plurality of number of times of automatic maintenance.   Even when a delivery request for a new liquid ejection head from the user is not selected in the delivery flow, a flow may be configured such that the control section  70  transmits a delivery request for all new liquid storage bodies or new refill containers from the user to the server apparatus  80 .   The liquid ejection apparatus  11  may be provided with a mode in which almost all the liquids L in the liquid ejection apparatus  11  from the liquid storage bodies  28  to the liquid ejection head  54  are discharged from the liquid flow paths in the liquid ejection apparatus  11 . When a cause of a problem related to ejection is the liquid L, the mode is executed, and thus most of the liquid L that is the cause of the problem related to ejection is discharged from the liquid flow path in the liquid ejection apparatus  11 . Thereafter, since a new liquid storage body  28  is attached or the liquid storage body  28  is replenished with the liquid L from a new refill container such that the new liquid L flows into the liquid flow path in the liquid ejection apparatus  11 , the control section  70  can make a recovery from a problem related to ejection in the liquid ejection apparatus  11 .       

     Third Embodiment 
     Hereinafter, a delivery system including a liquid ejection apparatus and a liquid ejection apparatus according to a third embodiment will be described with reference to the drawings. The liquid ejection apparatus is, for example, an ink jet printer that ejects ink that is an example of a liquid, to performing printing on a medium such as paper. 
     As illustrated in  FIG.  13   , a delivery system  111  includes a liquid ejection apparatus  112  that ejects a liquid to perform printing, and a server  113  that can communicate with the liquid ejection apparatus  112 . The delivery system  111  may include a plurality of liquid ejection apparatuses  112  coupled to a single server  113 . 
     The liquid ejection apparatus  112  includes a control section  114  capable of communicating with the server  113  via a network NT. The control section  114  is configured with, for example, a computer, a processing circuit including a memory, and the like, and executes various processes executed by the liquid ejection apparatus  112  according to a program stored in the memory. 
     In the drawings, a direction of gravity is indicated by a Z axis when the liquid ejection apparatus  112  is placed on a horizontal plane, and directions along the horizontal plane are indicated by an X axis and a Y axis. The X axis, Y axis, and Z axis are orthogonal to each other. 
     The liquid ejection apparatus  112  may include a printing unit  117  performing printing on a medium  116  and a reading unit  118  reading an image of an original document (not illustrated). The liquid ejection apparatus  112  may include a medium storage section  119  capable of storing a plurality of media  116 , and a discharge section  120  from which the printed medium  116  is discharged. The liquid ejection apparatus  112  may include an operation section  121  configured with buttons and the like for performing various operations on the liquid ejection apparatus  112 , and a display section  122  displaying information. The display section  122  may be a touch panel. 
     The liquid ejection apparatus  112  includes a liquid ejection head  124  that ejects a liquid onto the medium  116  to perform printing, and a liquid storage body  125  that stores the liquid to be supplied to the liquid ejection head  124 . The liquid ejection apparatus  112  may include a liquid supply flow path  126  through which a liquid is supplied from the liquid storage body  125  to the liquid ejection head  124 , and a carriage  127  that movably holds the liquid ejection head  124 . A part of the liquid supply flow path  126  may be configured with, for example, a tube that is deformed following the carriage  127  that is being moved. 
     The liquid ejection apparatus  112  may include a casing  130  provided with a window portion  129  that exposes a part of the liquid storage body  125  to the outside, and a casing cover  131  provided above the liquid storage body  125 . The casing cover  131  is movably provided at a closing position illustrated in  FIG.  13    and an opening position illustrated in  FIG.  14   . 
     The liquid ejection apparatus  112  may include a plurality of liquid storage bodies  125  fixed in the casing  130 . The casing  130  of the present embodiment stores four liquid storage bodies  125 , and the casing  130  is provided with four window portions  129  corresponding to the respective liquid storage body  125 . When the liquid storage body  125  is made of, for example, a transparent or translucent resin, a liquid level of the stored liquid is visible from the window portion  129 . The liquid storage body  125  may be provided with a scale  133  at a position exposed from the window portion  129 . 
     As illustrated in  FIG.  14   , the liquid ejection apparatus  112  has a holding portion  135  that holds a plurality of liquid storage bodies  125  in a state of being arranged in the X axis direction, and a residual amount detector  136  that detects an amount of the liquid stored in the liquid storage body  125 . As the residual amount detector  136 , for example, a reflection type optical sensor, a transmission type optical sensor, an electrode pin, or a capacitance sensor may be used. 
     The liquid storage body  125  has a storage chamber  138  storing the liquid and a pour  140  used for refilling the storage chamber  138  with the liquid from the refill container  139 . The liquid storage body  125  may have a tubular portion  141  through which the pour  140  is opened. The holding portion  135  of the present embodiment includes a plug  142  that closes the pour  140 . The plug  142  is movably provided between a closing position illustrated in  FIG.  15    at which the pour  140  is closed and a refill position illustrated in  FIG.  14    at which the pour  140  is opened. The refill of the liquid storage body  125  with the liquid is performed by inserting the refill container  139  into the tubular portion  141  in a state in which the casing cover  131  is located at the opening position and the plug  142  is located at the refill position. 
     When color printing is possible with the liquid ejection apparatus  112 , the plurality of liquid storage bodies  125  respectively store different types of liquids. For example, the four liquid storage bodies  125  respectively store liquids with corresponding colors such as black, cyan, magenta, and yellow. 
     As illustrated in  FIG.  15   , the liquid ejection apparatus  112  of the present embodiment includes a pour cover  144  that covers a plurality of pours  140 , and performs monochromatic printing exclusively. The pour cover  144  covers the pours  140  of the liquid storage bodies  125  for colors corresponding to cyan, magenta, and yellow. One liquid storage body  125  having the pour  140  that is not covered with the pour cover  144  stores, for example, a black liquid. 
     As illustrated in  FIG.  16   , the pour cover  144  includes a hook  145  that is engaged with the holding portion  135 , a cap  146  that is covered with the tubular portion  141 , and a positioning portion  147  that positions the pour cover  144  with respect to the holding portion  135 . 
     As illustrated in  FIG.  17   , the holding portion  135  has a plurality of through-holes  149  through which the tubular portions  141  pass. The pour cover  144  is attached to the holding portion  135  by hooking the hook  145  to an edge of the through-hole  149 . The holding portion  135  is fixed to the plurality of liquid storage bodies  125  in a state in which the pour cover  144  is attached, and the pour cover  144  is fitted to the cap  146  at the tip of the tubular portion  141  and thus movement thereof in the X axis direction and the Y axis direction is restricted. 
     Next, a description will be made of a refill routine executed by the control section  114  with reference to flowcharts of  FIGS.  18  and  19   . The control section  114  executes the refill routine at a timing at which power of the liquid ejection apparatus  112  is turned on. 
     As illustrated in  FIG.  18   , in step S 1101 , the control section  114  determines whether or not a refill flag is on. When the refill flag is off, a determination result in step S 1101  is NO, and the control section  114  causes the process to proceed to step S 1104 . When the refill flag is on, the determination result in step S 1101  is YES, and the control section  114  causes the process to proceed to step S 1102 . In step S 1102 , the control section  114  determines whether or not a refill timing at which the liquid storage body  125  is required to be refilled with the liquid has come. 
     Based on a detection result from the residual amount detector  136 , when a residual amount of the liquid stored in the liquid storage body  125  is more than a residual amount threshold value, the control section  114  determines that the refill timing of the liquid storage body  125  has not come, and a determination result in step S 1102  is NO. The control section  114  waits until the refill timing comes. 
     When the residual amount is equal to or less than the residual amount threshold value, the control section  114  determines that the refill timing has come, and the determination result in step S 1102  is YES. The control section  114  causes the process to proceed to step S 1103 . In step S 1103 , the control section  114  turns on the refill flag. 
     In step S 1104 , the control section  114  checks a delivery status of the new refill container  139  with the server  113 . In step S 1105 , the control section  114  determines whether or not the new refill container  139  has been sent. When the new refill container  139  has already been sent, a determination result in step S 1105  is YES, and the control section  114  causes the process to proceed to step S 1106 . 
     In step S 1106 , the control section  114  determines whether the new refill container  139  has arrived at the user. When the control section  114  has received a delivery completion notification transmitted from the server  113 , the control section  114  determines that the new refill container  139  has arrived, and a determination result in step S 1106  is YES. The control section  114  causes the process to proceed to step S 1107 . 
     In step S 1107 , the control section  114  prohibits printing. In step S 1108 , the control section  114  performs display for prompting refill with the liquid on the display section  122 . In step S 1109 , the control section  114  determines whether or not the refill of the liquid storage body  125  is completed. When the refill is not completed, a determination result in step S 1109  is NO, and the control section  114  waits until the refill is completed. When the refill is completed, the determination result in step S 1109  is YES, and the control section  114  causes the process to proceed to step S 1110 . In step S 1110 , the control section  114  turns off the refill flag and causes the process to proceed to step S 1102 . 
     In step S 1105 , when the new refill container  139  has not been sent, a determination result in step S 1105  is NO. The control section  114  causes the process to proceed to step S 1111 . In step S 1111 , the control section  114  requests the server  113  to send the new refill container  139 , and causes the process to proceed to step S 1112 . 
     When the control section  114  has not received the delivery completion notification in step S 1106 , the control section  114  determines that the new refill container  139  has not arrived, and a determination result in the step S 1106  is NO. The control section  114  causes the process to proceed to step S 1112 . 
     In step S 1112 , the control section  114  displays, on the display section  122 , attention when printing is continued. In step S 1113 , the control section  114  displays the estimated arrival date of the new refill container  139  on the display section  122 . In step S 1114 , the control section  114  displays a screen from which printing continuation can be selected on the display section  122 . 
     In step S 1115 , the control section  114  determines whether or not to continue printing. When the user does not select to continue printing, a determination result in step S 1115  is NO, and the control section  114  causes the process to proceed to step S 1107 . When the user selects to continue printing, the determination result in step S 1115  is YES, and the control section  114  causes the process to proceed to step S 1201 . 
     As illustrated in  FIG.  19   , in step S 1201 , the control section  114  determines whether or not the delivery completion notification transmitted from the server  113  has been received. When the delivery completion notification has not been received, a determination result in step S 1201  is NO. The control section  114  causes the process to proceed to step S 1202 . In step S 1202 , the control section  114  determines whether or not a predetermined period has elapsed from the refill timing. When the predetermined period has elapsed, the determination result in step S 1202  is YES, and the control section  114  causes the process to proceed to step S 1203 . 
     In step S 1203 , the control section  114  prohibits printing. In step S 1204 , the control section  114  determines whether or not the delivery completion notification transmitted from the server  113  has been received. When the delivery completion notification has not been received, a determination result in step S 1204  is NO, and the control section  114  waits until the delivery completion notification is received. When the delivery completion notification has been received, the determination result in step S 1204  is YES, and the control section  114  causes the process to proceed to step S 1108 . 
     When the predetermined period has not elapsed in step S 1202 , a determination result in step S 1202  is NO, and the control section  114  causes the process to proceed to step S 1205 . In step S 1205 , the control section  114  displays attention on the display section  122  according to an amount of the consumed liquid, and causes the process to proceed to step S 1201 . 
     When the delivery completion notification has been received in step S 1201 , the determination result in step S 1201  is YES, and the control section  114  causes the process to proceed to step S 1206 . In step S 1206 , the control section  114  performs display for prompting refill with the liquid on the display section  122 . 
     In step S 1207 , the control section  114  determines whether or not the refill of the liquid to the liquid storage body  125  is completed. When the refill is completed, the determination result in step S 1207  is YES, and the control section  114  causes the process to proceed to step S 1208 . In step S 1208 , the control section  114  turns off the refill flag and causes the process to proceed to step S 1102 . 
     When the refill is not completed in step S 1207 , a determination result in step S 1207  is NO, and the control section  114  causes the process to proceed to step S 1209 . In step S 1209 , when the predetermined period has elapsed from the refill timing, a determination result in step S 1209  is YES, and the control section  114  causes the process to proceed to step S 1107 . When the predetermined period has not elapsed from the refill timing, the determination result in step S 1209  is NO, and the control section  114  causes the process to proceed to step S 1210 . In step S 1210 , the control section  114  displays attention on the display section  122  according to an amount of the consumed liquid, and causes the process to proceed to step S 1206 . 
     An operation of the present embodiment will be described. 
     The control section  114  checks a delivery status of the new refill container  139  with the server  113  at a refill timing at which the liquid storage body  125  needs to be refilled with the liquid. 
     As illustrated in  FIG.  20   , when the new refill container  139  has been sent and has arrived at the refill timing, the control section  114  may prohibit printing and display a refill prompting screen for prompting refill with the liquid on the display section  122 . When the operation section  121  is operated by the user and information indicating that the refill is completed is input, the control section  114  may determine that the refill with the liquid is completed. The control section  114  may determine that the refill is completed when a residual amount of the liquid stored in the liquid storage body  125  is more than the residual amount threshold value. 
     As illustrated in  FIG.  21   , when the new refill container  139  has not been sent at the refill timing, the display section  122  may display a sending check screen for checking sending of the new refill container  139  on the display section  122 . When the operation section  121  is operated by the user and sending of the new refill container  139  is selected, the control section  114  makes a sending request to the server  113 . When sending of the new refill container  139  is not selected, control  114  prohibits printing until the liquid storage body  125  is completely refilled with a liquid or sending of the new refill container  139  is selected. 
     As illustrated in  FIG.  22   , the control section  114  that has made the sending request for the refill container  139  displays a continuation selection screen on the display section  122 , so that the control section  114  brings a state in which continuation of temporary printing is selectable after calling attention. The continuation selection screen may include attention when continuation of printing is selected and the estimated arrival date of the new refill container  139 . That is, the control section  114  may display the estimated arrival date of the new refill container  139  on the display section  122 . The control section  114  temporarily continues printing when the user selects continuation. The control section  114  prohibits printing when the user selects stop. 
     As illustrated in  FIG.  22   , the control section  114  may display the continuation selection screen on the display section  122  even when the new refill container  139  has been sent but has not arrived at the refill timing. That is, the control section  114  brings a state in which continuation of temporary printing is selectable after calling attention. 
     As illustrated in  FIG.  14   , in the liquid storage body  125  at the refill timing, for example, a liquid level of the stored liquid is at the bottom scale  133 , and thus the liquid remains. When the continuation of temporary printing is selected at the refill timing, the liquid ejection apparatus  112  performs printing with the liquid remaining in the liquid storage body  125 . 
     In a state where printing can be temporarily continued, the control section  114  may change a content of attention in accordance with an amount of the liquid consumed after the refill timing. For example, the control section  114  may gradually increase the degree of attention by changing a color and wording of the attention as a consumption amount increases. Specifically, when there is concern that the liquid in the liquid storage body  125  is not left and thus air may enter the liquid supply flow path  126 , the control section  114  may increase the degree of attention. When there is concern that the liquid in the liquid supply flow path  126  is not left and air may enter the liquid ejection head  124 , the control section  114  may further increase the degree of attention. The control section  114  may increase the degree of attention each time a print job is executed. 
     When the new refill container  139  arrives at the user, the server  113  transmits a delivery completion notification to the liquid ejection apparatus  112 . When the delivery completion notification of the new refill container  139  is received from the server  113  in a state in which printing can be temporarily continued, the control section  114  may perform display for prompting refill with the liquid on the display section  122  until the liquid storage body  125  is refilled with the liquid. Specifically, the control section  114  displays the refill prompting screen illustrated in  FIG.  20    on the display section  122 . 
     After receiving the delivery completion notification from the server  113 , the control section  114  may prohibit printing when a period in which refill with the liquid is not performed exceeds a predetermined period. The predetermined period may be, for example, a period until execution of a print job is finished when a delivery completion notification is received while printing is being executed, or a period in which a predetermined amount of the liquid is consumed. 
     When continuation of printing is selected at the refill timing and printing is executed, the control section  114  fills the liquid supply flow path  126  and the liquid ejection head  124  with the liquid when the liquid storage body  125  is refilled with the liquid. The filling with the liquid may be performed by, for example, cleaning in which the liquid in the liquid ejection head  124  is subjected to negative pressure or pressurization and thus the liquid is forced to be discharged from a nozzle (not illustrated). 
     The effects of the present embodiment will be described. 
     (1) At a refill timing at which the liquid storage body  125  needs to be refilled with a liquid, a small amount of the liquid remains in the liquid storage body  125 , the liquid supply flow path  126  coupling the liquid storage body  125  to the liquid ejection head  124 , and the liquid ejection head  124 . However, when printing is performed by using the liquid, there is concern that air may enter the liquid supply flow path  126  and the liquid ejection head  124 , and thus it is necessary to perform work of filling the liquid supply flow path  126  and the liquid ejection head  124  with the liquid in the future. In relation to this fact, the control section  114  checks a delivery status of the new refill container  139  with the server  113  at the refill timing, and brings a state in which continuation of temporary printing is selectable after calling attention when the refill container  139  has been sent but has not arrived. Thus, the user can check the delivery status of the new refill container  139  at the refill timing, and can temporarily continue printing even when the new refill container  139  has not arrived. Thus, it is possible to reduce concern that a period in which printing is to be stopped may occur. 
     (2) At the refill timing, the control section  114  makes a sending request to the server  113  when the new refill container  139  has not been sent. Thus, it is possible to save the user&#39;s time and effort to prepare the new refill container  139 . 
     (3) The control section  114  displays the estimated arrival date of the new refill container  139  on the display section  122 . Thus, the user can use the estimated arrival date to determine whether to temporarily continue printing or wait for the arrival of the new refill container  139 . 
     (4) For example, when printing is continued until the liquid in the liquid ejection head  124  is not left, there is concern that defective ejection may occur even after the liquid ejection head  124  is filled with the liquid. In relation to this fact, when the control section  114  receives a delivery completion notification of the new refill container  139  from the server  113 , the control section  114  continues to perform display for prompting refill with the liquid on the display section  122  until the liquid storage body  125  is refilled with the liquid. Thus, it is possible to reduce concern that the liquid in the liquid ejection head  124  may not be left. 
     (5) The control section  114  prohibits printing when a period in which refill with the liquid is not performed exceeds a predetermined period after a delivery completion notification of the new refill container  139  is received. When the control section  114  receives the delivery completion notification from the server  113 , the new refill container  139  is delivered to the user, and the user is ready to refill the liquid storage body  125  with the liquid from the refill container  139 . Thus, it is possible to reduce concern that printing is continued without refill with the liquid even after the refill container  139  arrives. 
     (6) When continuation of temporary printing is selected at the refill timing, concern that the liquid in the liquid ejection head  124  may not be left increases as an amount of the consumed liquid increases. In relation to this fact, the control section  114  changes a content of attention according to an amount of the consumed liquid. Thus, the user can be informed of the high probability that the liquid in the liquid ejection head  124  may not be left. 
     (7) When the new refill container  139  has been sent and has arrived at the refill timing, the control section  114  prohibits printing and performs display for prompting refill with the liquid on the display section  122 . Thus, it is possible to reduce concern that printing may be continued without refill with the liquid. 
     Fourth Embodiment 
     Hereinafter, a delivery system including a liquid ejection apparatus and a liquid ejection apparatus according to a fourth embodiment will be described with reference to the drawings. The fourth embodiment is different from the third embodiment in that the liquid storage body is attachable and detachable. The fourth embodiment is substantially the same as the third embodiment except for the above content, and thus an overlapping description will not be repeated by giving the same reference numeral to the same constituent. 
     As illustrated in  FIG.  23   , a delivery system  111  includes a liquid ejection apparatus  112  and a server  113  that can communicate with the liquid ejection apparatus  112 . The liquid ejection apparatus  112  includes a liquid ejection head  124  that ejects a liquid onto a medium  116  to perform printing, and a control section  114  that can communicate with the server  113  via a network NT. The liquid ejection apparatus  112  includes an attachment portion  152  to which a cartridge  151 , which is an example of a liquid storage body storing a liquid to be supplied to the liquid ejection head  124 , is detachably attached. The attachment portion  152  may include a supply needle  153  forming a part of the liquid supply flow path  126 , and an electrical coupling portion  154  which is electrically coupled to the control section  114 . 
     The cartridge  151  may include a storage medium  156  that stores information regarding the cartridge  151 . The storage medium  156  is, for example, an IC chip. The storage medium  156  may store the type of liquid stored in the cartridge  151 , an amount of the liquid stored in the cartridge  151 , an identifier of the cartridge  151 , and the like. The control section  114  may calculate an amount of the liquid stored in the cartridge  151  based on the information stored in the storage medium  156 , and rewrite the information stored in the storage medium  156 . 
     The storage medium  156  is electrically coupled to the electrical coupling portion  154 , and the cartridge  151  attached to the attachment portion  152  can cause the stored liquid to flow out via the supply needle  153 . The liquid stored in the cartridge  151  is supplied to the liquid ejection head  124  via the supply needle  153  and the liquid supply flow path  126 . 
     The control section  114  can read information stored in the storage medium  156  or write information into the storage medium  156  when the electrical coupling portion  154  is electrically coupled to the storage medium  156 . The electrical coupling portion  154  may be a connector that enables communication by contacting the storage medium  156 , or may be a radio that wirelessly reads and writes information from and into the storage medium  156 . 
     Next, a replacement routine executed by the control section  114  will be described with reference to flowcharts of  FIGS.  24  and  25   . The control section  114  executes the replacement routine at a timing at which power of the liquid ejection apparatus  112  is turned on. 
     As illustrated in  FIG.  24   , in step S 1301 , the control section  114  determines whether or not a replacement flag is on. When the replacement flag is off, a determination result in step S 1301  is NO, and the control section  114  causes the process to proceed to step S 1304 . When the replacement flag is on, the determination result in step S 1301  is YES, and the control section  114  causes the process to proceed to step S 1302 . In step S 1302 , the control section  114  determines whether or not a replacement timing at which the cartridge  151  is required to be replaced comes. 
     When a residual amount of the liquid stored in the cartridge  151  is more than a residual amount threshold value, the control section  114  determines that the replacement timing of the cartridge  151  has not come, and a determination result in step S 1302  is NO. The control section  114  waits until the replacement timing comes. 
     When the residual amount is equal to or less than the residual amount threshold value, the control section  114  determines that the replacement timing has come, and the determination result in step S 1302  is YES. The control section  114  causes the process to proceed to step S 1303 . In step S 1303 , the control section  114  turns on the replacement flag. 
     In step S 1304 , the control section  114  checks a delivery status of the new cartridge  151  with the server  113 . In step S 1305 , the control section  114  determines whether the new cartridge  151  has been sent. When the new cartridge  151  has already been sent, a determination result in step S 1305  is YES, and the control section  114  causes the process to proceed to step S 1306 . 
     In step S 1306 , the control section  114  determines whether the new cartridge  151  has arrived at the user. When the control section  114  has received a delivery completion notification transmitted from the server  113 , the control section  114  determines that the new cartridge  151  has arrived, and a determination result in step S 1306  is YES. The control section  114  causes the process to proceed to step S 1307 . 
     In step S 1307 , the control section  114  prohibits printing. In step S 1308 , the control section  114  performs display for prompting replacement of the cartridge  151  on the display section  122 . In step S 1309 , the control section  114  determines whether or not the replacement of the cartridge  151  is completed. When the replacement is not completed, a determination result in step S 1309  is NO, and the control section  114  waits until the replacement is completed. When the replacement is completed, the determination result in step S 1309  is YES, and the control section  114  causes the process to proceed to step S 1310 . In step S 1310 , the control section  114  turns off the replacement flag and causes the process to proceed to step S 1302 . 
     In step S 1305 , when the new cartridge  151  has not been sent, the determination result in step S 1305  is NO. The control section  114  causes the process to proceed to step S 1311 . In step S 1311 , the control section  114  requests the server  113  to send the new cartridge  151 , and causes the process to proceed to step S 1312 . 
     When the control section  114  has not received the delivery completion notification in step S 1306 , the control section  114  determines that the new cartridge  151  has not arrived, and the determination result in step S 1306  is NO. The control section  114  causes the process to proceed to step S 1312 . 
     In step S 1312 , the control section  114  displays, on the display section  122 , attention when printing is continued. In step S 1313 , the control section  114  displays the estimated arrival date of the new cartridge  151  on the display section  122 . In step S 1314 , the control section  114  displays a screen on the display section  122  on which printing continuation can be selected. 
     In step S 1315 , the control section  114  determines whether or not to continue printing. When the user does not select to continue printing, a determination result in step S 1315  is NO, and the control section  114  causes the process to proceed to step S 1307 . When the user selects to continue printing, the determination result in step S 1315  is YES, and the control section  114  causes the process to proceed to step S 1401 . 
     As illustrated in  FIG.  25   , in step S 1401 , the control section  114  determines whether or not the delivery completion notification transmitted from the server  113  has been received. When the delivery completion notification has not been received, a determination result in step S 1401  is NO. The control section  114  causes the process to proceed to step S 1402 . In step S 1402 , the control section  114  determines whether or not a predetermined period has elapsed from the replacement timing. When the predetermined period has elapsed, a determination result in step S 1402  is YES, and the control section  114  causes the process to proceed to step S 1403 . 
     In step S 1403 , the control section  114  prohibits printing. In step S 1404 , the control section  114  determines whether or not a delivery completion notification transmitted from the server  113  has been received. When the delivery completion notification has not been received, a determination result in step S 1404  is NO, and the control section  114  waits until the delivery completion notification is received. When the delivery completion notification has been received, the determination result in step S 1404  is YES, and the control section  114  causes the process to proceed to step S 1308 . 
     When the predetermined period has not elapsed in step S 1402 , the determination result in step S 1402  is NO, and the control section  114  causes the process to proceed to step S 1405 . In step S 1405 , the control section  114  displays attention on the display section  122  according to an amount of the consumed liquid, and causes the process to proceed to step S 1401 . 
     When the delivery completion notification is received in step S 1401 , the determination result in step S 1401  is YES, and the control section  114  causes the process to proceed to step S 1406 . In step S 1406 , the control section  114  performs display for prompting replacement of the cartridge  151  on the display section  122 . 
     In step S 1407 , the control section  114  determines whether or not the replacement of the cartridge  151  is completed. When the replacement is completed, a determination result in step S 1407  is YES, and the control section  114  causes the process to proceed to step S 1408 . In step S 1408 , the control section  114  turns off the replacement flag and causes the process to proceed to step S 1302 . 
     When the replacement is not completed in step S 1407 , the determination result in step S 1407  is NO, and the control section  114  causes the process to proceed to step S 1409 . In step S 1409 , when a predetermined period has elapsed from the replacement timing, a determination result in step S 1409  is YES, and the control section  114  causes the process to proceed to step S 1307 . When the predetermined period has not elapsed from the replacement timing, the determination result in step S 1409  is NO, and the control section  114  causes the process to proceed to step S 1410 . In step S 1410 , the control section  114  displays attention on the display section  122  according to an amount of the consumed liquid, and causes the process to proceed to step S 1406 . 
     An operation of the present embodiment will be described. 
     The control section  114  checks a delivery status of the new cartridge  151  with the server  113  at a replacement timing at which the cartridge  151  is required to be replaced. 
     As illustrated in  FIG.  26   , when the new cartridge  151  has been sent and has arrived at the replacement timing, the control section  114  may prohibit printing and display a replacement prompting screen for prompting replacement of the cartridge  151  on the display section  122 . When the operation section  121  is operated by the user and information indicating that the replacement is completed is input, the control section  114  may determine that the replacement of the cartridge  151  is completed. The control section  114  may determine that the replacement is completed based on information stored in the storage medium  156 . 
     As illustrated in  FIG.  27   , when the new cartridge  151  has not been sent at the replacement timing, the display section  122  may display a sending check screen for checking sending of the new cartridge  151  on the display section  122 . When the operation section  121  is operated by the user and sending of the new cartridge  151  is selected, the control section  114  makes a sending request to the server  113 . When sending of the new cartridge  151  is not selected, the control section  114  prohibits printing until the replacement of the cartridge  151  is completed or sending of the new cartridge  151  is selected. 
     As illustrated in  FIG.  28   , the control section  114  that has made the sending request for the new cartridge  151  displays a continuation selection screen on the display section  122 , so that the control section  114  brings a state in which continuation of temporary printing is selectable after calling attention. The continuation selection screen may include attention when continuation of printing is selected and the estimated arrival date of the new cartridge  151 . That is, the control section  114  may display the estimated arrival date of the new cartridge  151  on the display section  122 . The control section  114  temporarily continues printing when the user selects continuation. The control section  114  prohibits printing when the user selects stop. 
     As illustrated in  FIG.  28   , the control section  114  may display the continuation selection screen on the display section  122  even when the new cartridge  151  has been sent but has not arrived at the replacement timing. That is, the control section  114  brings a state in which continuation of temporary printing is selectable after calling attention. When continuation of temporary printing is selected at the replacement timing, the liquid ejection apparatus  112  performs printing with the liquid remaining in the cartridge  151 . 
     In a state where printing can be temporarily continued, the control section  114  may change a content of attention in accordance with an amount of the liquid consumed after the replacement timing. For example, the control section  114  may gradually increase the degree of attention by changing a color and wording of the attention as a consumption amount increases. 
     For example, in the cartridge  151  in which a liquid level of the stored liquid is in contact with air, there is concern that air may enter the liquid supply flow path  126  and the liquid ejection head  124 , similarly to the liquid storage body  125 . Thus, the degree of attention may be increased as in the third embodiment. 
     The cartridge  151  may store a liquid in a flexible storage bag. The storage bag collapses as the liquid is supplied. As an amount of the liquid stored in the storage bag decreases, the storage bag becomes less likely to collapse and thus the liquid becomes less likely to be supplied. Thus, as a residual amount of the cartridge  151  decreases, a speed at which the liquid can be supplied may become slower. When a consumption rate of consuming the liquid in printing is higher than a supply rate of supplying the liquid from the cartridge  151 , there is concern that air may enter the liquid supply flow path  126  and the liquid ejection head  124  from the nozzle (not illustrated) to cause defective ejection. Therefore, the control section  114  may increase the degree of attention so as to reduce the consumption rate as the consumption amount increases and the residual amount decreases. 
     When the new cartridge  151  arrives at the user, the server  113  transmits a delivery completion notification to the liquid ejection apparatus  112 . When the delivery completion notification of the new cartridge  151  is received from the server  113  in a state where printing can be temporarily continued, the control section  114  may perform display for prompting replacement of the cartridge  151  on the display section  122  until the cartridge  151  is replaced. Specifically, the control section  114  displays the replacement prompting screen illustrated in  FIG.  26    on the display section  122 . 
     After receiving the delivery completion notification from the server  113 , the control section  114  may prohibit printing when a period in which the cartridge  151  is not replaced exceeds a predetermined period. The predetermined period may be, for example, a period until execution of a print job is finished when a delivery completion notification is received while printing is being executed, or a period in which a predetermined amount of the liquid is consumed. 
     In a case where continuation of printing is selected and printing is executed at the replacement timing, the control section  114  cleans the liquid ejection head  124  and forces the liquid to be discharged from the nozzle when the cartridge  151  is replaced. 
     The effects of the present embodiment will be described. 
     (8) At a replacement timing at which the cartridge  151  is required to be replaced, a small amount of a liquid remains in the cartridge  151 , the liquid supply flow path  126  coupling the cartridge  151  to the liquid ejection head  124 , and the liquid ejection head  124 . However, when printing is performed by using the liquid, there is concern that air may enter the liquid supply flow path  126  and the liquid ejection head  124 , and thus it is necessary to perform work of filling the liquid supply flow path  126  and the liquid ejection head  124  with the liquid in the future. In relation to this fact, the control section  114  checks a delivery status of the new cartridge  151  with the server  113  at the replacement timing, and brings a state in which continuation of temporary printing is selectable after calling attention when the cartridge  151  has been sent but has not arrived. Thus, the user can check the delivery status of the new cartridge  151  at the replacement timing, and can temporarily continue printing even when the new cartridge  151  has not arrived. Thus, it is possible to reduce concern that a period in which printing is to be stopped may occur. 
     (9) At the replacement timing, the control section  114  makes a sending request to the server  113  when the new cartridge  151  has not been sent. Thus, it is possible to save the user&#39;s time and effort to prepare the new cartridge  151 . 
     (10) The control section  114  displays the estimated arrival date of the new cartridge  151  on the display section  122 . Thus, the user can use the estimated arrival date to determine whether to temporarily continue printing or wait for the arrival of the new cartridge  151 . 
     (11) When the control section  114  receives a delivery completion notification of the new cartridge  151  from the server  113 , the control section  114  continues to perform display for prompting replacement on the display section  122  until the cartridge  151  is replaced. Thus, it is possible to reduce concern that the liquid in the liquid ejection head  124  may not be left. 
     (12) The control section  114  prohibits printing when a period in which replacement with the new cartridge  151  is not performed exceeds a predetermined period after receiving a delivery completion notification of the new cartridge  151 . When the control section  114  receives the delivery completion notification from the server  113 , the new cartridge  151  is delivered to the user, and the user is ready to replace the cartridge  151 . Thus, it is possible to reduce concern that printing is continued without replacing the cartridge  151  even after the new cartridge  151  arrives. 
     (13) When continuation of temporary printing is selected at the replacement timing, concern that the liquid in the liquid ejection head  124  may not be left increases as an amount of the consumed liquid increases. In relation to this fact, the control section  114  changes a content of attention according to an amount of the consumed liquid. Thus, the user can be informed of the high probability that the liquid in the liquid ejection head  124  may not be left. 
     (14) When the new cartridge  151  has been sent and has arrived at the replacement timing, the control section  114  prohibits printing and performs display for prompting replacement on the display section  122 . Thus, it is possible to reduce concern that printing may be continued without replacement with the new cartridge  151 . 
     The present embodiment may be modified and implemented as follows. The present embodiment and the following modification examples may be implemented in combination with each other within a technically consistent scope.
         In the refill routine illustrated in  FIGS.  18  and  19   , as in the flowchart of  FIG.  29   , steps S 1206  to S 1210  may be omitted. That is, in step S 1201 , when the delivery completion notification has been received, the determination result in step S 1201  is YES, and the control section  114  may cause the process to proceed to step S 1107 . When the delivery completion notification of the new refill container  139  is received from the server  113  in a state where printing can be temporarily continued, the control section  114  may immediately prohibit printing and perform display for prompting refill on the display section  122  until the liquid storage body  125  is refilled with the liquid. Consequently, it is possible to reduce concern that the liquid in the liquid ejection head  124  may not be left.   In the replacement routine illustrated in  FIGS.  24  and  25    as in the flowchart of  FIG.  30   , steps S 1406  to S 1410  may be omitted. That is, in step S 1401 , when the delivery completion notification is received, the determination result in step S 1401  is YES, and the control section  114  may cause the process to proceed to step S 1307 . When the delivery completion notification of the new cartridge  151  is received from the server  113  in a state where printing can be temporarily continued, the control section  114  may immediately prohibit printing and perform display for prompting replacement on the display section  122  until replacement with the new cartridge  151  is performed. Consequently, it is possible to reduce concern that the liquid in the liquid ejection head  124  may not be left.   The holding portion  135  may be provided with a label indicating the type of stored liquid. The label may be provided to correspond to each liquid storage body  125 . The pour cover  144  may cover a label corresponding to the unused liquid storage body  125  together with the pour  140  of the unused liquid storage body  125 .   The liquid ejection apparatus  112  may store different types of liquids in the plurality of liquid storage bodies  125 , respectively. In this case, the control section  114  may bring a state in which continuation of temporary printing is selectable after calling attention at a refill timing of any one of the liquid storage bodies  125 .   A plurality of cartridges  151  may be attached to the attachment portion  152 . In this case, the control section  114  may bring a state in which continuation of temporary printing is selectable after calling attention at a replacement timing of any one of the cartridges  151 .   The liquid ejection apparatus  112  may include an attachment detector detecting that the cartridge  151  is attached to the attachment portion  152 . The control section  114  may determine whether or not the cartridge  151  has been replaced based on a detection result from the attachment detector.   The control section  114  may set a printing speed when a temporarily printable state is selected to be lower than that during normal printing at the refill timing or the replacement timing. For example, the control section  114  may set a movement speed of the carriage  127  when a temporarily printable state is selected to be lower than that during normal printing. In a case of a line head in which the liquid ejection head  124  is provided over a width direction of the medium  116 , a transport speed of the medium  116  when a temporarily printable state is selected may be set to be lower than that during normal printing. The control section  114  may reduce an amount of a liquid ejected by the liquid ejection head  124  per unit time.   The control section  114  may change a content of attention when a temporarily printable state is selected according to data to be printed at the refill timing or the replacement timing. For example, the control section  114  may call more attention when a printing rate is high than when the printing rate is low. The control section  114  may call more attention when a size of the printing medium  116  is large than when the size of the printing medium  116  is small. The control section  114  may call more attention when the number of media  116  to be printed is large than when the number of media  116  to be printed is small.   When the refill timing is earlier than arrival of the refill container  139 , or the replacement timing is earlier than arrival of the cartridge  151 , the server  113  may store an earlier period. In the case of the subscription type liquid ejection apparatus  112  in which a charge is generated according to a period of use, each of a period from the refill timing to arrival of the refill container  139  and a period from the replacement timing to arrival of the cartridge  151  is a period during which printing cannot be performed in a correct state. Thus, the delivery system  111  may return, to the user, services such as refunds, gifts, and plan content changes according to the period stored in the server  113 .   The liquid ejection apparatus  112  may include an estimation section that estimates a refill timing based on an amount of a liquid consumed per predetermined period and an amount of a liquid filling the refill container  139 . The liquid ejection apparatus  112  may include a sending request section that requests the server  113  to send the refill container  139  before only a delivery period required for delivery of the refill container  139  based on the refill timing estimated by the estimation section. When the new refill container  139  has not arrived at the refill timing, the estimation section may correct the next refill timing to be earlier and advance the sending request.   The liquid ejection apparatus  112  may include an estimation section that estimates the replacement timing based on an amount of liquid consumed per predetermined period and an amount of liquid stored in the new cartridge  151 . The liquid ejection apparatus  112  may include a sending request section that requests the server  113  to send the cartridge  151  only the delivery period required for delivering the cartridge  151  before the replacement timing estimated by the estimation section. When the new refill container  139  has not arrived at the replacement timing, the estimation section may correct the next replacement timing to be earlier and advance the sending request.   The control section  114  may display attention regardless of an amount of a liquid consumed in a state in which printing can be temporarily continued.   The control section  114  may bring a state in which continuation of temporary printing is selectable even when a period in which refill or replacement is not performed exceeds a predetermined period after a delivery completion notification is received.   When the delivery completion notification is received from the server  113  in a state where printing can be temporarily continued, the control section  114  may continuously, intermittently, or temporarily perform display for prompting refill or replacement.   The control section  114  does not need to display the estimated arrival date of the new refill container  139  or the new cartridge  151  on the display section  122 . The control section  114  may perform a notification of the estimated arrival date with voice, for example.   When the refill container  139  or the cartridge  151  has not been sent at the refill timing or the replacement timing, the control section  114  may automatically request the refill container  139  or the cartridge  151  to be sent regardless of the user&#39;s operation. The control section  114  may request the refill container  139  or the cartridge  151  to be sent at a timing different from the refill timing or the replacement timing. The control section  114  may check a delivery status of the refill container  139  or the cartridge  151  regardless of the refill timing or the replacement timing.   The liquid ejection apparatus  112  may be a liquid ejection apparatus that jets or ejects a liquid other than ink. A state of a liquid ejected as a minute amount of liquid droplets from the liquid ejection apparatus includes granular, tear-like, or thread-like tail. The liquid mentioned here may be any material that can be ejected from the liquid ejection apparatus. For example, the liquid may be in a state when a substance is in a liquid phase, and includes fluids such as high-viscosity or low-viscosity liquids, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals, and metal melts. The liquid includes not only a liquid as a state of a substance but also a liquid in which particles of a functional material made of a solid substance such as a pigment or a metal particle are dissolved, dispersed or mixed in a solvent. Typical examples of the liquid include ink as described in the above embodiment and liquid crystal. Here, the ink includes general water-based ink, oil-based ink, and gel ink, and various liquid compositions such as hot melt ink. Specific examples of the liquid ejection apparatus include a liquid crystal display, an electroluminescence display, a surface light emitting display, and an apparatus that ejects a liquid containing a material such as an electrode material or a coloring material used for manufacturing a color filter or the like in a dispersed or dissolved form. The liquid ejection apparatus may be an apparatus ejecting a bioorganic substance used for producing a biochip, an apparatus ejecting a liquid as a sample used as a precision pipette, a textile printer, a micro dispenser, or the like. The liquid ejection apparatus may be an apparatus ejecting a lubricating oil to a precision machine such as a timepiece or a camera in a pinpoint manner, or an apparatus ejecting, onto a substrate, a transparent resin liquid such as an ultraviolet curable resin in order to form a micro hemispherical lens or an optical lens, or the like used for an optical communication element or the like. The liquid ejection apparatus may be an apparatus that ejects an acid or alkali etching solution in order to etch a substrate or the like.       

     The technical spirit and its operations and effects understood from the above-described embodiments and modifications are described below. 
     (A) A liquid ejection apparatus includes a liquid ejection head that is detachably attached and ejects a liquid, and a control section that is configured to transmit a delivery request for a new liquid ejection head to a server apparatus via a network. 
     According to this configuration, delivery of a new replacement liquid ejection head can be requested when needed. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (B) The liquid ejection apparatus may further include a detector that detects a problem related to the ejection, and the control section may be configured to transmit the delivery request for the new liquid ejection head when the detector detects the problem. 
     According to this configuration, it is possible to request delivery of a new replacement liquid ejection head when a problem related to ejection occurs. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (C) In the liquid ejection apparatus, the control section may start a check flow including the delivery request for the new liquid ejection head when the detector detects the problem. 
     According to this configuration, when a problem occurs in the liquid ejection head, it is possible to request delivery of a new replacement liquid ejection head depending on a state of the problem of the liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (D) The liquid ejection apparatus may further include a maintenance section that performs maintenance on the liquid ejection head, the detector may have a function of detecting defective ejection of the liquid ejection head, the control section may perform automatic maintenance of causing the maintenance section to automatically execute the maintenance when the detector detects the defective ejection, and the detector may detect that the automatic maintenance was repeatedly executed a predetermined number of times or more as the problem. 
     According to this configuration, in a case where there is defective ejection that is not solved even when the automatic maintenance was repeatedly executed a predetermined number of times or more, it is possible to request delivery of a new replacement liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (E) The liquid ejection apparatus may further include a maintenance section that performs maintenance on the liquid ejection head, and the detector may detect that the maintenance was repeatedly executed by a user a predetermined number of times or more as the problem. 
     According to this configuration, in a case where a problem that is not solved occurs even when maintenance was repeatedly executed by the user a predetermined number of times or more, it is possible to request delivery of a new replacement liquid ejection head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (F) The liquid ejection apparatus may further include an input section that is configured for the user to input occurrence of the problem. 
     According to this configuration, when the user determines that the liquid ejection head has a problem, appropriate measures can be taken. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (G) In the liquid ejection apparatus, when the user inputs the occurrence of the problem to the input section, the control section may start a check flow including the delivery request for the new liquid ejection head. 
     According to this configuration, when the user inputs the occurrence of a problem related to ejection, it is possible to take measures according to a status at that time. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (H) The liquid ejection apparatus may further include a maintenance section that performs maintenance on the liquid ejection head, and the control section may start the check flow according to an execution status of the maintenance before the occurrence of the problem is input to the input section. 
     According to this configuration, when the user inputs the occurrence of the problem related to ejection, it is possible to take measures according to an execution status of the maintenance before the input. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (I) In the liquid ejection apparatus, the control section may prohibit use of the liquid ejection apparatus when the delivery request for the new liquid ejection head is transmitted. 
     According to this configuration, in the liquid ejection apparatus, it is possible to prevent printing from being continued in the liquid ejection head having a problem related to ejection. 
     (J) In the liquid ejection apparatus, the control section may cancel the prohibition of use of the liquid ejection apparatus after transmitting the delivery request for the new liquid ejection head on condition of a request from the user. 
     According to this configuration, even when there is a problem with the liquid ejection head, printing can be continued until a new liquid ejection head arrives, depending on the user&#39;s request. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus. 
     (K) In the liquid ejection apparatus, when the delivery request for the new liquid ejection head is made, in a case where there is a liquid storage body of which a residual amount is less than a predetermined threshold value among a plurality of liquid storage bodies storing liquids to be supplied to the liquid ejection head, the control section may transmit a delivery request for a new liquid storage body in addition to the delivery request for the new liquid ejection head. 
     According to this configuration, in the liquid ejection apparatus, it is also possible to request delivery of a new liquid storage body corresponding to a liquid storage body having a small residual amount in accordance with a delivery timing of the liquid ejection head. 
     (L) In the liquid ejection apparatus, a plurality of liquid storage bodies storing liquids to be supplied to the liquid ejection head may be accommodated, each of the liquid storage bodies has a supply port used for replenishment with a liquid stored in a refill container, and, when the delivery request for the new liquid ejection head is made, in a case where there is a liquid storage body of which a residual amount is less than a predetermined threshold value among the plurality of liquid storage bodies storing the liquids to be supplied to the liquid ejection head, the control section may transmit a delivery request for a new refill container in addition to the delivery request for the new liquid ejection head. 
     According to this configuration, in the liquid ejection apparatus, it is also possible to request delivery of the refill container for replenishing the liquid storage body having a small residual amount with a liquid in accordance with a delivery timing of the liquid ejection head. 
     (M) The liquid ejection apparatus may further include a liquid storage body that stores the liquid to be supplied to the liquid ejection head, the liquid storage body may have a storage chamber storing the liquid and a pour through which the storage chamber is refilled with the liquid from a refill container, and the control section may check a delivery status of the new refill container with the server apparatus at a refill timing at which the liquid storage body is required to be refilled with the liquid, and bring a state in which continuation of temporary printing is selectable after calling attention when the new refill container was sent but was not arrived. 
     According to this configuration, the control section checks a delivery status of the new refill container with the server at the refill timing, and brings a state in which continuation of temporary printing is selectable after calling attention when the refill container was sent but was not arrived. Thus, the user can check a delivery status of the new refill container at the refill timing, and can temporarily continue printing even when the new refill container was not arrived. Thus, it is possible to reduce concern that a period in which printing is to be stopped may occur. 
     (N) A delivery system for a liquid ejection head includes the liquid ejection apparatus including a liquid ejection head that is detachably attached and ejects a liquid, and a control section that is configured to transmit a delivery request for a new liquid ejection head to a server apparatus via a network; and the server apparatus including a reception section that receives the delivery request for the new liquid ejection head transmitted from the control section. 
     According to this configuration, when a problem occurs in the liquid ejection head, the liquid ejection head can be replaced with a new head. Consequently, it is possible to reduce downtime caused by the absence of a new replacement liquid ejection head at a user&#39;s hand when a problem occurs in the liquid ejection head in the liquid ejection apparatus.