Image recording device, billing system, and billing method

Abstract

To provide means that prevents a user from suffering a disadvantage when the user replaces a cartridge while liquid is left in a tank.SOLUTION: A printer 10 includes: a fitting case 150 capable of fitting a contract cartridge or a commercial cartridge thereto; a sub-tank 160 for storing ink supplied from a cartridge 200 fitted to the fitting case 150; a head 21 connected to the sub-tank 160 and including a nozzle 29 for discharging ink; a memory; and a controller 130. The controller 130 can transition to a contract mode and a non-contract mode. In the contract mode, the controller stores an amount of ink supplied from a contract cartridge and stored in the sub-tank 160 when the contract cartridge is fitted to the fitting case 150 and an amount of ink supplied from a commercial cartridge and stored in the sub-tank 160 when the commercial cartridge is fitted to the fitting case 150 in the memory.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to an image recording device, a billing system for image recording, and a billing method for image recording. [Background technology]

[0002] A printer user may enter into a contract with a printer sales company and use the printer in accordance with the contract. For example, the user may enter into a contract under which, in exchange for paying a fee, they can use ink free of charge until they have printed a specified number of pages (hereinafter referred to as the contracted number of pages). Under this contract, when the printer runs low on ink, the sales company will send the user a cartridge filled with ink. As long as the number of pages printed is below the contracted number, the user will not be charged for ink or cartridges.

[0003] Patent document 1 describes an image recording device that can be fitted with a tank that contains ink and has a sub-tank, in which if the fitted tank does not meet specified conditions, ink is not replenished from the tank to the sub-tank, but if the tank meets the specified conditions, ink is replenished from the tank to the sub-tank. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-094705 Summary of the Invention [Problem to be solved by the invention]

[0005] Consider a case where a user enters into a contract for a printer that can accommodate cartridges and has a subtank, allowing the user to use ink free of charge until the number of pages printed reaches the contracted number. Until the contract is signed, the user purchases commercially available cartridges and prints using the ink stored in the commercially available cartridges. After the contract is signed, the user prints using the ink stored in cartridges sent by the sales company (hereinafter referred to as contract cartridges).

[0006] After signing the contract, the user replaces the cartridge installed in the printer from the commercially available cartridge to the contract cartridge. At the time of cartridge replacement, the ink supplied from the commercially available cartridge remains in the subtank. After the cartridge replacement, the subtank stores both the ink supplied from the commercially available cartridge and the ink supplied from the contract cartridge, and printing is performed using both inks.

[0007] The user has already paid for the ink stored in the subtank that was supplied from the commercially available cartridge. Therefore, if the printer performs billing processing (counting the number of printed pages, etc.) in accordance with the contract immediately after the cartridge replacement, the user will suffer a financial disadvantage for the amount of ink supplied from the commercially available cartridge.

[0008] The present invention has been made in consideration of the above circumstances, and its purpose is to provide a means for preventing a user from suffering any disadvantage when replacing a cartridge while liquid remains in the tank. [Means for solving the problem]

[0009] (1) An image recording device according to the present invention includes a mounting portion capable of mounting a first cartridge or a second cartridge for storing liquid, a tank for storing liquid supplied from the first cartridge or the second cartridge mounted in the mounting portion, a head connected to the tank and having a nozzle for ejecting the liquid, a memory, and a controller. The controller is capable of transitioning between a first operating state in which a service contract using the first cartridge is made and a second operating state in which the service contract is not made, and stores in the memory in the first operating state a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is mounted in the mounting portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is mounted in the mounting portion.

[0010] The controller stores in memory the amount of liquid supplied from the first cartridge when the first cartridge is attached to the attachment portion and stored in the tank, and the amount of liquid supplied from the second cartridge when the second cartridge is attached to the attachment portion and stored in the tank. Therefore, by performing billing processing based on these amounts, it is possible to prevent the user from being disadvantaged when they replace the cartridge while there is liquid remaining in the tank.

[0011] (2) Preferably, the controller determines the type of cartridge attached to the attachment portion in response to a signal obtained from the first cartridge or the second cartridge attached to the attachment portion, updates the first tank liquid amount based on information obtained from the first cartridge in response to determining that the controller is in the first operating state and that the first cartridge has been attached to the attachment portion, and updates the second tank liquid amount based on information obtained from the second cartridge in response to determining that the controller is in the first operating state and that the second cartridge has been attached to the attachment portion.

[0012] (3) Preferably, the controller, in the first operating state, executes an update process in response to receiving an instruction to eject the liquid from the nozzle. In the update process, the controller adds the amount of change in the amount of liquid stored in the first cartridge to the first tank liquid amount in response to determining that the first cartridge is attached to the attachment portion, adds the amount of change in the amount of liquid stored in the second cartridge to the second tank liquid amount in response to determining that the second cartridge is attached to the attachment portion, calculates a consumption amount which is the sum of the amount of change in the amount of liquid stored in the cartridge attached to the attachment portion and the amount of liquid stored in the tank, subtracts the consumption amount from the second tank liquid amount in response to the second tank liquid amount being equal to or greater than the consumption amount, and subtracts the difference between the consumption amount and the second tank liquid amount from the first tank liquid amount in response to the second tank liquid amount being less than the consumption amount, thereby updating the second tank liquid amount to zero.

[0013] (4) Preferably, the memory stores a flag. In the update process, the controller sets the flag to a second value when the second tank liquid amount is equal to or greater than the consumption amount, and sets the flag to a first value when the second tank liquid amount is less than the consumption amount. The controller executes a billing process when the flag is the first value after executing the update process.

[0014] (5) Preferably, a plurality of the mounting portions are provided, each of which can accommodate a cartridge corresponding to one of a plurality of colors. The memory stores a plurality of flags corresponding to the plurality of colors. The controller executes the update process for each of the cartridges mounted in the plurality of mounting portions, and executes the charging process in response to at least one of the plurality of flags having the first value after the update process has been executed.

[0015] (6) Preferably, the image recording device further includes a notification unit that notifies the user that a charge has been made. The controller operates the notification unit in the charge processing.

[0016] (7) Preferably, the image recording device further includes a communication interface for communicating with a server, and the controller transmits an instruction to execute charging to the server through the communication interface in the charging process.

[0017] (8) Preferably, in the second operating state, the controller stores the first tank liquid amount and the second tank liquid amount together as one amount in the memory.

[0018] (9) Preferably, the height of the liquid surface stored in the cartridge attached to the attachment portion is equal to the height of the liquid surface stored in the tank.

[0019] (10) A billing system according to the present invention includes an image recording device and a server connected to the image recording device. The image recording device includes a mounting portion capable of mounting a first or second cartridge for storing a liquid, a tank for storing the liquid supplied from the first or second cartridge mounted to the mounting portion, a head connected to the tank and having a nozzle for ejecting the liquid, a memory, and a controller. The controller is capable of transitioning between a first operating state in which a service contract using the first cartridge has been made and a second operating state in which the service contract has not been made, and in the first operating state, stores in the memory a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is attached to the attachment portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is attached to the attachment portion, and updates the first tank liquid amount and the second tank liquid amount in response to receiving an instruction to eject liquid from the nozzle in the first operating state, sets a billing flag to either a first value or a second value, and executes a first billing process in response to the controller having executed the first billing process.

[0020] (11) A billing method according to the present invention uses an image recording device and a server connected to the image recording device. The image recording device includes a mounting portion capable of mounting a first cartridge or a second cartridge for storing a liquid, a tank for storing the liquid supplied from the first cartridge or the second cartridge mounted in the mounting portion, a head connected to the tank and having a nozzle for ejecting the liquid, a memory, and a controller. The controller is capable of transitioning between a first operating state in which a service using the first cartridge is subscribed to and a second operating state in which the service is not subscribed to. The billing method includes a step in which the controller, in the first operating state, stores in the memory a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is attached to the attachment portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is attached to the attachment portion; a step in which the controller, in the first operating state and in response to receiving an instruction to eject liquid from the nozzle, updates the first tank liquid amount and the second tank liquid amount and sets a billing flag to either a first value or a second value; a step in which the controller, in response to the billing flag being the first value, executes a first billing process; and a step in which the server, in response to the controller executing the first billing process. [Effects of the Invention]

[0021] According to the above configuration, it is possible to prevent the user from suffering any disadvantage when the user replaces the cartridge while liquid remains in the tank. [Brief explanation of the drawings]

[0022] [Figure 1] 1A and 1B are external perspective views of the printer 10, in which FIG. 1A shows a state in which a cover 87 is in a covering position, and FIG. 1B shows a state in which the cover 87 is in an exposing position. [Figure 2] FIG. 2 is a schematic cross-sectional view showing the internal structure of the printer 10. As shown in FIG. [Figure 3] FIG. 3 is a vertical cross-sectional view of the attachment case 150. As shown in FIG. [Figure 4] 4A and 4B are diagrams showing the structure of the cartridge 200, with FIG. 4A showing a front perspective view and FIG. 4B showing a vertical cross-sectional view. [Figure 5] FIG. 5 is a vertical cross-sectional view of the cartridge 200 attached to the attachment case 150. As shown in FIG. [Figure 6] FIG. 6 is a schematic diagram showing a state in which the subtank 160 and the cartridge 200 are in communication with each other. [Figure 7] FIG. 7 is a block diagram of the printer 10 and the billing server 300. [Figure 8] FIG. 8 is a diagram showing functions F1k and F2k. [Figure 9] FIG. 9 is a flowchart showing the operation of the controller 130. [Figure 10] FIG. 10 is a flowchart of the ink amount calculation process when the cartridge is installed. [Figure 11] FIG. 11 is a flowchart of the ink consumption operation and the ink amount calculation process when ink is consumed. [Figure 12] FIG. 12 is a flowchart of the subtank remaining amount calculation process when the cartridge is installed. [Figure 13] FIG. 13 is a flowchart of the process for calculating the remaining amount of ink in the subtank when ink is consumed. DETAILED DESCRIPTION OF THE INVENTION

[0023] An embodiment of the present invention will be described below. Note that the embodiment described below is merely one example of the present invention, and it goes without saying that the embodiment of the present invention can be modified as appropriate without departing from the spirit of the present invention. Furthermore, the up-down direction 7 is defined based on the use position in which the printer 10 is installed on a horizontal surface so that it can be used, the front-to-back direction 8 is defined with the surface of the printer 10 on which the opening 13 is formed as the front, and the left-to-right direction 9 is defined when viewing the printer 10 from the front. In this embodiment, in the use position, the up-down direction 7 corresponds to the vertical direction, and the front-to-back direction 8 and the left-to-right direction 9 correspond to the horizontal direction. The front-to-back direction 8 and the left-to-right direction 9 are perpendicular to each other.

[0024] [Printer 10 Overview] The printer 10 according to this embodiment is an example of an image recording device that records an image on a sheet using an inkjet recording method. The printer 10 has a roughly rectangular parallelepiped housing 14. The printer 10 may be a so-called "multifunction device" that has functions such as a facsimile function, a scanning function, and a copying function.

[0025] As shown in Figures 1 and 2, inside the housing 14 are located a feed tray 15, a feed roller 23, a conveying roller 25, a head 21 having multiple nozzles 29, a platen 26 facing the head 21, an ejection roller 27, an ejection tray 16, an attachment case 150 in which the cartridge 200 can be attached, and a tube 32 that connects the cartridge 200 attached to the attachment case 150 and the head 21.

[0026] The printer 10 drives the feed roller 23 and the transport roller 25 to transport the sheet supported on the feed tray 15 to the position of the platen 26. Next, the printer 10 causes the head 21 to eject ink (an example of liquid) supplied from the cartridge 200 mounted in the mounting case 150 through the tube 32 via the nozzle 29. This causes the ink to land on the sheet supported on the platen 26, recording an image on the sheet. The printer 10 drives the discharge roller 27 to discharge the sheet on which the image has been recorded onto the discharge tray 16.

[0027] The head 21 may be mounted on a carriage that moves back and forth in a main scanning direction that intersects with the direction of sheet transport by the transport rollers 25. The printer 10 may cause the head 21 to eject ink through the nozzles 29 while moving the carriage from one side to the other in the main scanning direction. This causes an image to be recorded on a portion of the sheet facing the head 21. Next, the printer 10 may cause the transport rollers 25 to transport the sheet so that the area on which the next image is to be recorded faces the head 21. By alternately and repeatedly executing these processes, an image is recorded on one sheet.

[0028] [Cover 87] As shown in FIG. 1, an opening 85 is formed on the front surface 14A of the housing 14 at the right end in the left-right direction 9. The housing 14 further includes a cover 87. The cover 87 is rotatable between a covered position (position shown in FIG. 1(A)) in which the opening 85 is closed and an exposed position (position shown in FIG. 1(B)) in which the opening 85 is open. The cover 87 is supported by the housing 14, for example, near the lower end of the housing 14 in the up-down direction 7, so as to be rotatable about a rotation axis along the left-right direction 9. Four attachment cases 150 are located in an accommodation space inside the housing 14 that extends beyond the opening 85.

[0029] [Mounting Case 150] The printer 10 has four mounting cases 150 corresponding to the four colors of black, yellow, cyan, and magenta. Each mounting case 150 can accommodate a cartridge 200 corresponding to one of black, yellow, cyan, and magenta.

[0030] In the following description, if there are four elements corresponding to four colors, the element corresponding to black will be referred to as the “black element,” the element corresponding to yellow will be referred to as the “yellow element,” the element corresponding to cyan will be referred to as the “cyan element,” and the element corresponding to magenta will be referred to as the “magenta element.” For example, the cartridge 200 corresponding to black will be referred to as the black cartridge 200.

[0031] 3, each mounting case 150 includes a contact 152, a rod 153, a mounting sensor 154, a liquid level sensor 155, and a lock pin 156. The number of mounting cases 150 included in the printer 10 is not limited to four, and may be three or less, or five or more. The mounting case 150 is an example of a mounting unit.

[0032] The four attachment cases 150 form an internal space 86 that houses the four cartridges 200. This internal space 86 is defined by a top wall that defines the upper end, a bottom wall that defines the lower end, a rear wall that defines the rear end in the front-to-rear direction 8, and a pair of side walls that define both ends in the left-to-right direction 9. An opening 85 is formed at a position facing the rear wall. When the cover 87 is placed in the exposed position, the opening 85 exposes the internal spaces 86 of the four attachment cases 150 to the outside of the printer 10. The cartridges 200 are inserted into and removed from the attachment cases 150 through the opening 85 in the housing 14.

[0033] [Contact 152] The contact 152 is located on the top wall of the mounting case 150 and protrudes downward from the top wall toward the internal space 86 of the mounting case 150. The contact 152 is located at a position where it comes into contact with an electrode 248 (described below) of the cartridge 200 when the cartridge 200 is mounted in the mounting case 150. The contact 152 is conductive and is elastically deformable in the up-down direction 7. The contact 152 is electrically connected to the controller 130.

[0034] [Rod 153] The rod 153 protrudes forward from the rear wall of the mounting case 150. The rod 153 is located above a joint 180 (described later) on the rear wall of the mounting case 150. During the process of mounting the cartridge 200 to the mounting case 150, the rod 153 enters the atmospheric valve chamber 214 through an atmospheric communication port 221 (described later) of the cartridge 200. When the rod 153 enters the atmospheric valve chamber 214, the atmospheric valve chamber 214 (described later) is connected to the atmosphere.

[0035] [Wearing Sensor 154] The attachment sensor 154 is located on the top wall of the attachment case 150. The attachment sensor 154 is a sensor that allows the controller 130 to detect whether or not the cartridge 200 is attached to the attachment case 150. The attachment sensor 154 includes a light-emitting portion and a light-receiving portion that are spaced apart in the left-right direction 9. When the cartridge 200 is attached to the attachment case 150, a light-shielding rib 245 (described below) of the cartridge 200 is located between the light-emitting portion and the light-receiving portion of the attachment sensor 154. In other words, the light-emitting portion and the light-receiving portion of the attachment sensor 154 are located opposite each other, with the light-shielding rib 245 of the cartridge 200 attached to the attachment case 150 in between.

[0036] The wearing sensor 154 outputs signals of different levels (hereinafter referred to as wearing signals) depending on whether light emitted from the light-emitting unit in the left-right direction 9 is received by the light-receiving unit. For example, the wearing sensor 154 outputs a low-level wearing signal when the received light intensity of the light received by the light-receiving unit is less than a threshold intensity, and outputs a high-level wearing signal when the received light intensity is equal to or greater than the threshold intensity. The controller 130 receives the four wearing signals output from the four wearing sensors 154.

[0037] [Liquid level sensor 155] The liquid level sensor 155 is a sensor used by the controller 130 to detect whether a detection target 194 of the actuator 190 (described later) is located at the detection position. The liquid level sensor 155 includes a light-emitting element and a light-receiving element spaced apart in the left-right direction 9. In other words, the light-emitting element and the light-receiving element of the liquid level sensor 155 are positioned facing each other, sandwiching the detection target 194 located at the detection position. The liquid level sensor 155 outputs signals of different levels (hereinafter referred to as liquid level signals) depending on whether light output from the light-emitting element is received by the light-receiving element. For example, the liquid level sensor 155 outputs a low-level liquid level signal when the intensity of light received by the light-receiving element is less than a threshold intensity, and outputs a high-level liquid level signal when the intensity of the received light is equal to or greater than the threshold intensity. The controller 130 receives the four liquid level signals output from the four liquid level sensors 155.

[0038] [Lock pin 156] The lock pin 156 is a rod-shaped member extending in the left-right direction 9 at the upper end of the internal space 86 of the attachment case 150 and near the opening 85. Both ends of the lock pin 156 in the left-right direction 9 are fixed to a pair of side walls that partition the internal spaces 86 of the four attachment cases 150. The lock pin 156 extends in the left-right direction 9 within this internal space 86. When the cartridge 200 is attached to the attachment case 150, it engages with the lock pin 156. As a result, the cartridge 200 attached to the attachment case 150 is held in the attachment position shown in FIG. 5.

[0039] [Subtank 160] The printer 10 is equipped with four subtanks 160 corresponding to the four cartridges 200, respectively. The subtanks 160 are located further rearward than the rear wall of the mounting case 150. As shown in FIG. 3, the subtank 160 is composed of an upper wall 161, a front wall 162, a lower wall 163, a rear wall 164, and a pair of side walls (not shown). A liquid chamber 171 is formed inside the subtank 160. Of the walls constituting the subtank 160, at least the wall facing the liquid level sensor 155 is translucent. Therefore, light output by the liquid level sensor 155 can pass through the wall facing the liquid level sensor 155. The four subtanks 160 have a generally common configuration. The subtank 160 is an example of a tank.

[0040] The liquid chamber 171 is connected to an ink flow path (not shown) through the outlet 174. The lower end of the outlet 174 is defined by a lower wall 163 that defines the lower end of the liquid chamber 171. The outlet 174 is located lower in the up-down direction 7 than the joint 180 (more specifically, the lower end of the through-hole 184). The ink flow path that is connected to the outlet 174 is connected to a tube 32 (see FIG. 2). Therefore, the liquid chamber 171 is connected to the head 21 from the outlet 174 through the ink flow path and the tube 32. Ink stored in the liquid chamber 171 is supplied to the head 21 from the outlet 174 through the ink flow path and the tube 32.

[0041] The liquid chamber 171 is in communication with the atmosphere through an atmosphere communication chamber 175. More specifically, the atmosphere communication chamber 175 is in communication with the liquid chamber 171 through a through-hole 176 that penetrates the front wall 162. The atmosphere communication chamber 175 is in communication with the outside of the printer 10 through an atmosphere communication port 177 and a tube (not shown) connected to the atmosphere communication port 177. The atmosphere communication chamber 175 is in communication with the atmosphere through the atmosphere communication port 177 and the tube.

[0042] [Joint 180] As shown in Figure 3, the joint 180 includes a needle 181 and a guide 182. The needle 181 is a tube with a flow path formed therein, and protrudes forward from the front wall 162 that defines the liquid chamber 171. An opening 183 is formed at the protruding tip of the needle 181. The internal space of the needle 181 communicates with the liquid chamber 171 via a through-hole 184 that penetrates the front wall 162. The guide 182 protrudes forward from the front wall 162, and its protruding end is open.

[0043] A valve 185 and a coil spring 186 are positioned in the internal space of the needle 181. The valve 185 is movable in the internal space of the needle 181 in the front-to-rear direction 8 between a closed position where the opening 183 is closed and an open position where the opening 183 is open. The coil spring 186 biases the valve 185 in a direction that moves the valve 185 from the open position to the closed position, i.e., forward.

[0044] [Actuator 190] An actuator 190 is positioned in the liquid chamber 171. The actuator 190 is supported by a support member (not shown) disposed within the liquid chamber 171 so as to be rotatable in the directions of arrows 198 and 199. The actuator 190 can rotate between the position indicated by the solid line and the position indicated by the dashed line in FIG. 3. A stopper (not shown) restricts the actuator 190 from rotating in the direction of arrow 198 from the solid line position. The actuator 190 includes a float 191, a shaft 192, an arm 193, and a detection target 194.

[0045] The float 191 is made of a material with a lower specific gravity than the ink stored in the liquid chamber 171. The shaft 192 protrudes in the left-right direction 9 from the right and left surfaces of the float 191. The shaft 192 is inserted into a hole (not shown) formed in a support member. This allows the actuator 190 to be supported by the support member so as to be rotatable around the shaft 192. The arm 193 extends substantially upward from the float 191. The detection target portion 194 is located at the protruding tip of the arm 193. The detection target portion 194 is a plate-shaped member that extends in the up-down direction 7 and the front-rear direction 8. The detection target portion 194 is made of a material or color that blocks light output from the light-emitting portion of the liquid level sensor 155.

[0046] When the ink level in the liquid chamber 171 is equal to or higher than a predetermined position P, the actuator 190 is rotated in the direction of arrow 198 by buoyancy and is held at the detection position shown by the solid line in FIG. 3 by a stopper. When the ink level is lower than the predetermined position P, the actuator 190 is rotated in the direction of arrow 199 following the drop in the ink level. As a result, the detection target 194 moves to a position away from the detection position. In this way, the detection target 194 moves to a position corresponding to the amount of ink stored in the liquid chamber 171.

[0047] The predetermined position P is indicated by an imaginary line extending horizontally at the same height as the axial center of the needle 181 in the vertical direction 7 and at the same height as the center of the ink supply port 234 (described later). Note that the predetermined position P is not limited to the above-mentioned position as long as it is a position above the outlet 174 in the vertical direction 7. The predetermined position P may be, for example, the height of the upper or lower end of the internal space of the needle 181, or the height of the upper or lower end of the ink supply port 234.

[0048] When the level of the ink stored in the liquid chamber 171 is above the predetermined position P, the light output from the light-emitting element of the liquid level sensor 155 is blocked by the detection target portion 194. At this time, the light from the light-emitting element does not reach the light-receiving element, and the liquid level sensor 155 outputs a low-level liquid level signal. When the level of the ink stored in the liquid chamber 171 is below the predetermined position P, the light output from the light-emitting element reaches the light-receiving element, and the liquid level sensor 155 outputs a high-level liquid level signal. The controller 130 can detect whether the level of the ink in the liquid chamber 171 is above the predetermined position P using the liquid level signal.

[0049] [Cartridge 200] The cartridge 200 has a liquid chamber 210 (see FIG. 2) capable of storing ink therein. The liquid chamber 210 is defined by, for example, a resin wall. As shown in FIG. 4(A), the dimensions of the cartridge 200 along the up-down direction 7 and along the front-rear direction 8 are greater than the dimensions of the cartridge 200 along the left-right direction 9. The outer shapes of cartridges 200 storing inks of different colors may be the same or different.

[0050] The cartridge 200 includes a housing 201 and a supply pipe 230. The housing 201 is composed of a rear wall 202, a front wall 203, an upper wall 204, a lower wall 205, and a pair of side walls 206 and 207. The rear wall 202 is composed of multiple walls that are each offset in the front-to-rear direction 8. The upper wall 204 is composed of multiple walls that are each offset in the up-down direction 7. The lower wall 205 is composed of multiple walls that are each offset in the up-down direction 7.

[0051] As shown in FIG. 4(B), a liquid chamber 210, an ink valve chamber 213, and an atmospheric valve chamber 214 are formed in the internal space of the cartridge 200. The liquid chamber 210 has an upper liquid chamber 211 and a lower liquid chamber 212. The upper liquid chamber 211, the lower liquid chamber 212, and the atmospheric valve chamber 214 are internal spaces of the housing 201. The ink valve chamber 213 is an internal space of the supply pipe 230. The liquid chamber 210 stores ink. The atmospheric valve chamber 214 connects the liquid chamber 210 to the outside of the cartridge 200.

[0052] The upper liquid chamber 211 and the lower liquid chamber 212 of the liquid chamber 210 are separated in the up-down direction 7 by a partition wall 215 that separates the internal space of the housing 201. The upper liquid chamber 211 and the lower liquid chamber 212 are in communication with each other by a through-hole 216 formed in the partition wall 215. The upper liquid chamber 211 and the atmospheric valve chamber 214 are separated in the up-down direction 7 by a partition wall 217 that separates the internal space of the housing 201. An upper surface 215U of the partition wall 215 separates the upper liquid chamber 211. A lower surface 215L of the partition wall 215 separates the lower liquid chamber 212. The upper liquid chamber 211 and the atmospheric valve chamber 214 are in communication with each other by a through-hole 218 formed in the partition wall 217. The ink valve chamber 213 is in communication with the lower end of the lower liquid chamber 212 via a through-hole 219.

[0053] The atmospheric valve chamber 214 is connected to the outside of the cartridge 200 through an atmospheric vent port 221 formed in the rear wall 202 at the top of the cartridge 200. The atmospheric valve chamber 214 is connected to the atmosphere through the atmospheric vent port 221. A valve 222 and a coil spring 223 are positioned in the atmospheric valve chamber 214. The valve 222 is movable in the front-rear direction 8 between a closed position where the atmospheric vent port 221 is closed and an open position where the atmospheric vent port 221 is open. The coil spring 223 biases the valve 222 in a direction that moves it from the open position to the closed position, i.e., rearward.

[0054] During the process of mounting the cartridge 200 in the mounting case 150, the rod 153 enters the atmosphere valve chamber 214 through the atmosphere communication port 221. The rod 153 that has entered the atmosphere valve chamber 214 moves the valve 222, which is in the closed position, forward against the biasing force of the coil spring 223. As the valve 222 moves to the open position, the upper liquid chamber 211 is connected to the atmosphere.

[0055] The supply tube 230 protrudes rearward from the rear wall 202 at the bottom of the housing 201. The protruding end (rear end) of the supply tube 230 is open. The ink valve chamber 213 connects the liquid chamber 210, which is connected via the through-hole 219, with the outside of the cartridge 200. A packing 231, a valve 232, and a coil spring 233 are located in the ink valve chamber 213.

[0056] An ink supply port 234 is formed in the center of the packing 231, penetrating in the front-to-rear direction 8. The inner diameter of the ink supply port 234 is slightly smaller than the outer diameter of the needle 181. The valve 232 is movable in the front-to-rear direction 8 between a closed position and an open position. When the valve 232 is in the closed position, it abuts against the packing 231 to close the ink supply port 234, and when it is in the open position, it moves away from the packing 231 to open the ink supply port 234. The coil spring 233 biases the valve 232 in a direction that moves it from the open position to the closed position, i.e., backward. The biasing force of the coil spring 233 is greater than that of the coil spring 186.

[0057] During the process of mounting the cartridge 200 in the mounting case 150, the supply tube 230 enters the guide 182, and eventually the needle 181 enters the ink valve chamber 213 through the ink supply port 234. At this time, the needle 181 elastically deforms the packing 231 and comes into liquid-tight contact with the inner circumferential surface that defines the ink supply port 234. As the cartridge 200 is further inserted into the mounting case 150, the needle 181 moves the valve 232 forward against the biasing force of the coil spring 233. The valve 232 moves the valve 185, which protrudes from the opening 183 of the needle 181, rearward against the biasing force of the coil spring 186.

[0058] 5, the ink supply port 234 and the opening 183 are opened, and the ink valve chamber 213 of the supply tube 230 communicates with the internal space of the needle 181. In other words, when the cartridge 200 is attached to the attachment case 150, the ink valve chamber 213 and the internal space of the needle 181 form a flow path that communicates between the liquid chamber 210 of the cartridge 200 and the liquid chamber 171 of the subtank 160.

[0059] When the cartridge 200 is attached to the attachment case 150, a portion of the liquid chamber 210 and a portion of the liquid chamber 171 overlap each other when viewed horizontally. Therefore, the ink stored in the liquid chamber 210 moves to the liquid chamber 171 of the subtank 160 due to the hydraulic head difference through the connected supply pipe 230 and joint 180. As shown in FIG. 6 , the height of the liquid surface of the ink stored in the liquid chamber 210 of the cartridge 200 attached to the attachment case 150 is equal to the height of the liquid surface of the ink stored in the liquid chamber 171 of the subtank 160.

[0060] As shown in FIG. 4 , a protrusion 241 is formed on the upper wall 204. The protrusion 241 protrudes upward from the outer surface of the upper wall 204 and extends along the front-to-rear direction 8. The protrusion 241 has a locking surface 242 and an inclined surface 243. The locking surface 242 and the inclined surface 243 are located above the upper wall 204. The locking surface 242 faces forward in the front-to-rear direction 8 and extends in the up-down direction 7 and the left-to-right direction 9. The inclined surface 243 is inclined with respect to the upper wall 204 so as to face upward and rearward.

[0061] The locking surface 242 is a surface that comes into contact with the locking pin 156 when the cartridge 200 is attached to the attachment case 150. The inclined surface 243 is a surface that guides the locking pin 156 to a position where it comes into contact with the locking surface 242 during the process of attaching the cartridge 200 to the attachment case 150. When the locking surface 242 and the locking pin 156 come into contact with each other, the cartridge 200 is held in the attachment position shown in FIG. 5 against the biasing forces of the coil springs 186, 223, and 233.

[0062] A flat plate-shaped member is formed in front of the locking surface 242 and extending upward from the upper wall 204. The upper surface of this flat plate-shaped member is an operating portion 244 that is operated by the user when removing the cartridge 200 from the attachment case 150. When the cartridge 200 is attached to the attachment case 150 and the cover 87 is positioned in the exposed position, the operating portion 244 can be operated by the user. When the operating portion 244 is pressed downward, the cartridge 200 rotates, and the locking surface 242 moves downward beyond the locking pin 156. As a result, the cartridge 200 can be removed from the attachment case 150.

[0063] A light-shielding rib 245 is formed on the outer surface of the upper wall 204, behind the protrusion 241. The light-shielding rib 245 protrudes upward from the outer surface of the upper wall 204 and extends along the front-rear direction 8. The light-shielding rib 245 is made of a material or color that blocks light output from the light-emitting portion of the attachment sensor 154. When the cartridge 200 is attached to the attachment case 150, the light-shielding rib 245 is located on the optical path from the light-emitting portion to the light-receiving portion of the attachment sensor 154. The attachment sensor 154 outputs a low-level attachment signal when the cartridge 200 is attached to the attachment case 150, and outputs a high-level attachment signal when the cartridge 200 is not attached to the attachment case 150. The controller 130 can detect whether the cartridge 200 is attached to the attachment case 150 based on the attachment signal output from the attachment sensor 154.

[0064] An IC board 247 is located on the outer surface of the upper wall 204, between the light-shielding rib 245 and the protrusion 241 in the front-rear direction 8. Electrodes 248 are formed on the IC board 247. The IC board 247 includes a storage unit (not shown; hereinafter referred to as a cartridge storage unit). The electrodes 248 are electrically connected to the cartridge storage unit. The electrodes 248 are exposed on the upper surface of the IC board 247 so as to be electrically conductive with the contacts 152. When the cartridge 200 is attached to the attachment case 150, the electrodes 248 are electrically conductive with the contacts 152. The controller 130 can read information from the cartridge storage unit and write information to the cartridge storage unit via the contacts 152 and the electrodes 248.

[0065] The black, yellow, cyan, and magenta cartridge storage units store ink amounts Vck, Vcy, Vcc, and Vcm, respectively. In addition, each cartridge storage unit stores cartridge attribute information indicating the cartridge type (details will be described later), etc. When a cartridge 200 is unused, the cartridge storage unit stores an initial ink amount as the ink amount. The initial ink amount indicates the amount of ink stored in an unused cartridge 200.

[0066] [Controller 130] 7, the controller 130 includes a CPU 131, a ROM 132, a RAM 133, an EEPROM 134, and an ASIC 135. The ROM 132 stores programs and the like for the CPU 131 to execute various processes. The RAM 133 is used as a storage area for temporarily recording data, signals, and the like used when the CPU 131 executes the programs, or as a working area for data processing. The EEPROM 134 stores information that should be retained even after the power is turned off. The ROM 132, RAM 133, and EEPROM 134 are examples of memory.

[0067] The ASIC 135 is used to operate the feed roller 23, the transport roller 25, the discharge roller 27, and the head 21. The controller 130 rotates the feed roller 23, the transport roller 25, and the discharge roller 27 by driving a motor (not shown) through the ASIC 135. The controller 130 outputs a drive signal to a drive element of the head 21 through the ASIC 135, causing the head 21 to eject ink through the nozzles 29. The ASIC 135 can output multiple types of drive signals depending on the amount of ink to be ejected through the nozzles 29.

[0068] A display 17 and an operation panel 22 are connected to the ASIC 135. The display 17 is, for example, a liquid crystal display, an organic EL display, or the like. The display 17 is an example of an alarm unit. Note that the alarm unit is not limited to the display 17, and may be a speaker, an LED lamp, or a combination of these. The operation panel 22 outputs an operation signal to the controller 130 in response to an operation by the user. The operation panel 22 may have, for example, a push button, or a touch sensor superimposed on the display 17.

[0069] The ASIC 135 is connected to a contact 152, an attachment sensor 154, and a liquid level sensor 155. The controller 130 accesses the cartridge storage unit of the cartridge 200 attached to the attachment case 150 via the contact 152. The controller 130 detects the attachment and detachment of the cartridge 200 via the attachment sensor 154. The controller 130 detects via the liquid level sensor 155 whether the ink level in the liquid chamber 171 is above a predetermined position P.

[0070] A communication interface 140 is connected to the ASIC 135. The communication interface 140 is an interface for communicating with the billing server 300. The printer 10 controls the communication interface 140 to communicate with the billing server 300 via the communication network 350.

[0071] [Contract regarding Printer 10] A user of the printer 10 may enter into a contract with a sales company of the printer 10 and use the printer 10 in accordance with the contract. In this embodiment, as an example, consider a case where the sales company of the printer 10 provides a service in which the user can use ink free of charge until the number of prints reaches the contracted number in exchange for paying a fee.

[0072] Until signing up for the service, the user purchases commercially available cartridges and prints using the ink stored in the commercially available cartridges. The sales company sends cartridges 200 filled with ink to users who have signed up for the service. For example, the sales company sends cartridges 200 when the printer 10 runs low on ink. After signing up for the service, the user prints using the ink stored in the cartridges 200 sent by the sales company (hereinafter referred to as contract cartridges). Either contract cartridges or commercially available cartridges can be attached to the mounting case 150.

[0073] The controller 130 of the printer 10 operates in a contract mode when a service contract has been made, and in a non-contract mode when a service contract has not been made. The controller 130 can transition between the contract mode and the non-contract mode. The contract mode is a state in which a service contract has been made using a contract cartridge. The non-contract mode is a state in which a service contract has not been made using a contract cartridge. The contract cartridge is an example of a first cartridge. The commercially available cartridge is an example of a second cartridge. The contract mode is an example of a first operating state. The non-contract mode is an example of a second operating state.

[0074] Data and Information Used by Controller 130 ROM 132 stores ink amounts Vak, Vay, Vac, and Vam. Ink amount Vak is the total amount of black ink when the black liquid level signal changes from low to high. Ink amounts Vay, Vac, and Vam are the same as ink amount Vak, except for differences in color. Ink amounts Vak, Vay, Vac, and Vam are fixed values ​​determined according to the structure of the printer 10 and cartridge 200. If the structure of the printer 10 and cartridge 200 is the same for all four colors, ink amounts Vak, Vay, Vac, and Vam will be the same. In this case, ROM 132 may store only one ink amount.

[0075] In this embodiment, when the liquid level signal for each color changes from low level to high level, that is, when the ink level in the liquid chamber 171 falls below a predetermined position P, the amount of ink stored in the cartridge 200 for each color is 0, and the amount of ink stored in the subtank 160 for each color is equal to Vak, Vay, Vac, and Vam. For this reason, the ROM 132 stores the amount of ink stored in the subtank 160 for each color as Vak when the liquid level signal for each color changes from low level to high level.

[0076] In order for the controller 130 to execute the ink amount calculation process (described below), the EEPROM 134 stores ink amounts Vck, Vcy, Vcc, Vcm, ink amounts Vsk, Vsy, Vsc, Vsm, thresholds Vhk, Vhy, Vhc, Vhm, functions F1k, F1y, F1c, F1m, functions F2k, F2y, F2c, F2m, count values ​​SNk, SNy, SNc, SNm, and count values ​​TNk, TNy, TNc, TNm.

[0077] If the printer 10 and cartridge 200 have the same structure for all four colors, the thresholds Vhk, Vhy, Vhc, and Vhm will be the same. In this case, the EEPROM 134 may store only one threshold. The same applies to the functions F1k, F1y, F1c, and F1m, the functions F2k, F2y, F2c, and F2m, the count values ​​SNk, SNy, SNc, and SNm, and the count values ​​TNk, TNy, TNc, and TNm. The thresholds Vhk, Vhy, Vhc, and Vhm, the functions F1k, F1y, F1c, and F1m, and the functions F2k, F2y, F2c, and F2m may be stored in the ROM 132 instead of the EEPROM 134.

[0078] The ink amount Vck is the amount of ink stored in the liquid chamber 210 of the black cartridge 200. The ink amount Vsk is the amount of ink stored in the liquid chamber 171 of the black subtank 160. The functions F1k and F2k are information indicating the correspondence between the total amount Vtk of black ink in the printer 10 and the ink amount Vsk.

[0079] The ink stored in the liquid chamber 210 of the black cartridge 200 and the ink stored in the liquid chamber 171 of the black subtank 160 reach equilibrium when the positions of the liquid surfaces of the respective inks in the vertical direction 7 are the same. In this equilibrium state, movement of black ink between the liquid chamber 210 and the liquid chamber 171 stops. The relationship between the total amount Vtk of black ink and the ink amount Vsk in this equilibrium state can be approximated by a function that uses measured values.

[0080] As shown in Figure 8, the relationship between the total amount Vtk of black ink and the ink amount Vsk can be approximately represented by two functions F1k and F2k. The function F1k represents the relationship between the total amount Vtk and the ink amount Vsk when the total amount Vtk is equal to or greater than the threshold value Vhk, and is expressed, for example, as Vsk = a x Vtk + b (a and b are constants). The function F2k represents the relationship between the total amount Vtk and the ink amount Vsk when the total amount Vtk is less than the threshold value Vhk, and is expressed, for example, as Vsk = c x Vtk + d (c and d are constants).

[0081] The threshold value Vhk is a value equivalent to the total amount Vtk when the ink level stored in the upper liquid chamber 211 of the liquid chamber 210 of the black cartridge 200 comes into contact with the upper surface 215U or lower surface 215L of the partition 215. When the ink level in the liquid chamber 210 of the black cartridge 200 is above the partition 215 (i.e., when the total amount Vtk is equal to or greater than the threshold value Vhk), the ink amount Vsk is calculated using the function F1k. When the ink level in the liquid chamber 210 of the black cartridge 200 is in contact with the partition 215 or below the partition 215 (i.e., when the total amount Vtk is less than the threshold value Vhk), the ink amount Vsk is calculated using the function F2k. The ink amount Vck is calculated by subtracting the ink amount Vsk from the total amount Vtk.

[0082] The count value SNk is a value that is counted up by a value corresponding to the amount of black ink that the head 21 is instructed to discharge after the black liquid level signal changes from low level to high level. The count value TNk is a value that is counted up by a value corresponding to the amount of black ink that the head 21 is instructed to discharge after the black mounting signal changes from high level to low level. The initial values ​​of the count values ​​SNk and TNk are 0. Note that the count values ​​SNk and TNk may also be values ​​that are counted down from their respective initial values.

[0083] The ink amounts Vcy, Vcc, and Vcm are the same as the ink amount Vck, except for the difference in color. The ink amounts Vsy, Vsc, and Vsm are the same as the ink amount Vsk, except for the difference in color. The thresholds Vhy, Vhc, and Vhm are the same as the threshold Vhk, except for the difference in color. The functions F1y, F1c, and F1m are the same as the function F1k, except for the difference in color. The functions F2y, F2c, and F2m are the same as the function F2k, except for the difference in color. The count values ​​SNy, SNc, and SNm are the same as the count value SNk, except for the difference in color. The count values ​​TNy, TNc, and TNm are the same as the count value TNk, except for the difference in color.

[0084] In order for the controller 130 to execute the subtank remaining amount calculation process (described below), the EEPROM 134 stores operating mode information, contract information, four cartridge attribute information, ink amounts Vck', Vcy', Vcc', Vcm', ink amounts Vsk', Vsy', Vsc', Vsm', ink amounts SKk, SKy, SKc, SKm, and ink amounts SSk, SSy, SSc, SSm.

[0085] The operating mode information is information indicating whether the controller 130 operates in a contract mode or a non-contract mode. The contract information is information regarding the contract concluded between the user of the printer 10 and the distributor of the printer 10. The contract information is valid only when the operating mode information indicates the contract mode. The contract information includes, for example, a contract number. The operating mode information and the contract information are written to the EEPROM 134 by the user of the printer 10 or an operator of the distributor of the printer 10 operating the operation panel 22. The four cartridge attribute information is information stored in the four cartridge memory units.

[0086] The ink amount Vck' is the ink amount Vck when the subtank remaining amount calculation process was last performed. The ink amount Vsk' is the ink amount Vsk when the subtank remaining amount calculation process was last performed. The ink amount SKk is the amount of ink supplied from the black contract cartridge and stored in the black subtank 160. The ink amount SSk is the amount of ink supplied from the black commercially available cartridge and stored in the black subtank 160. The ink amounts Vcy', Vcc', and Vcm' are the same as the ink amount Vck' except for the difference in color. The ink amounts Vsy', Vsc', and Vsm' are the same as the ink amount Vsk' except for the difference in color. The ink amounts SKy, SKc, and SKm are the same as the ink amount SKk except for the difference in color. The ink amounts SSy, SSc, and SSm are the same as the ink amount SSk except for the difference in color.

[0087] The controller 130 stores in the EEPROM 134 the ink amounts SKk, SKy, SKc, and SKm supplied from the contract cartridges of each color when the contract cartridges of each color are attached to the mounting cases 150 of each color and stored in the subtanks 160 of each color, and the ink amounts SSk, SSy, SSc, and SSm supplied from the commercially available cartridges of each color when the commercially available cartridges of each color are attached to the mounting cases 150 of each color and stored in the subtanks 160 of each color. The ink amounts SKk, SKy, SKc, and SKm are examples of first tank liquid amounts. The ink amounts SSk, SSy, SSc, and SSm are examples of second tank liquid amounts.

[0088] In addition to the above data and information, the controller 130 stores various data. The various data include four pieces of first liquid level information, four pieces of second liquid level information, four flags FLAGk, FLAGy, FLAGc, and FLAGm, a billing flag, ink amounts Vtk, Vty, Vtc, and Vtm, ink change amounts Pk, Py, Pc, and Pm, ink consumption amounts Qk, Qy, Qc, and Qm, and ink change amounts Rk, Ry, Rc, and Rm. This data is stored in the RAM 132.

[0089] [Controller 130 Operation] The operation of the controller 130 will be described with reference to Figures 9 to 13. The processes shown in Figures 9 to 13 are repeatedly executed by the CPU 131 of the controller 130 while the printer 10 is powered on. The processes shown in Figures 9 to 13 may be executed by the CPU 131 reading out a program stored in the ROM 132, or may be implemented by a hardware circuit mounted on the controller 130. The order in which the processes are executed may be changed as appropriate without departing from the spirit of the present invention. In the following description, unless otherwise specified, it is assumed that data and information used by the controller 130 are stored in the RAM 133 or the EEPROM 134.

[0090] As shown in FIG. 9, the controller 130 determines whether any of the four attachment signals output from the four attachment sensors 154 has changed from high level to low level (S11). If the controller 130 determines that any of the attachment signals has changed from high level to low level (S11: Yes), the controller 130 proceeds to S12. In this case, the controller 130 executes the ink amount calculation process (FIG. 10) when the cartridge is attached (S12). Next, the controller 130 determines whether the operation mode information indicates the contract mode (S13: Yes). If the controller 130 determines that the operation mode information indicates the contract mode (S13: Yes), the controller 130 proceeds to S14. In this case, the controller 130 executes the subtank remaining amount calculation process (FIG. 12) when the cartridge is attached (S14), and proceeds to S15.

[0091] In response to determining in S13 that the operation mode information does not indicate the contract mode (i.e., indicates the non-contract mode) (S13: No), the controller 130 proceeds to S15 without executing S14. In response to determining in S11 that none of the attachment signals have changed from high level to low level (S11: No), the controller 130 proceeds to S15 without executing S12 to S14.

[0092] In S15, the controller 130 determines whether an instruction to operate the printer 10 has been received. The instruction to the controller 130 is input, for example, from a device (not shown, for example, a personal computer) connected to the printer 10 via a cable, LAN, or the like. Alternatively, the instruction to the controller 130 is input by a user of the printer 10 operating the operation panel 22. If the controller 130 determines that an instruction has been received (S15: Yes), it proceeds to S16, and if it determines that an instruction has not been received (S15: No), it proceeds to S11.

[0093] In S16, the controller 130 determines whether the received instruction is an ink consumption instruction. An ink consumption instruction is an instruction to eject ink from the nozzles 29 of the head 21 to reduce the amount of ink stored in the cartridges 200 and subtanks 160. Ink consumption instructions include print instructions, purging instructions, and the like. If the controller 130 determines that the received instruction is an ink consumption instruction (S16: Yes), the controller 130 proceeds to S18. If the controller 130 determines that the received instruction is not an ink consumption instruction (i.e., an instruction not to consume ink) (S16: No), the controller 130 proceeds to S17. In this case, the controller 130 executes an operation that does not consume ink (S17), and proceeds to S11.

[0094] In S18, the controller 130 executes an ink consumption operation and a process for calculating the amount of ink consumed (FIG. 11). Next, the controller 130 determines whether the operation mode information indicates the contract mode (S19). If the controller 130 determines that the operation mode information indicates the contract mode (S19: Yes), the controller 130 proceeds to S20. If the controller 130 determines that the operation mode information does not indicate the contract mode (i.e., indicates the non-contract mode) (S19: No), the controller 130 proceeds to S24 without executing S20 to S23.

[0095] In S20, the controller 130 executes the subtank remaining amount calculation process when ink is consumed (FIG. 13). As will be described later, the controller 130 sets the billing flag to ON or OFF in the subtank remaining amount calculation process when ink is consumed. Next, the controller 130 determines whether the billing flag set in the subtank remaining amount calculation process when ink is consumed is ON (S21). If the controller 130 determines that the billing flag is ON (S21: Yes), it proceeds to S22. If the controller 130 determines that the billing flag is not ON (i.e., the billing flag is OFF) (S21: No), it proceeds to S24 without executing S22 and S23.

[0096] In S22, the controller 130 transmits a charging instruction to the charging server 300. The charging instruction transmitted to the charging server 300 includes the contract number included in the contract information, information indicating that one sheet has been printed, and the like. Next, the controller 130 displays on the display 17 that the charging process is being executed (S23). When the controller 130 executes S23, a message such as "Charging process executed" is displayed on the display 17.

[0097] In S24, the controller 130 determines whether there are further instructions. For example, the controller 130 determines whether there are any pages remaining to be printed. If the controller 130 determines that there are further instructions (S24: Yes), the process proceeds to S18, and if the controller 130 determines that there are no further instructions (S24: No), the process proceeds to S11.

[0098] Thus, in the non-contract mode, the controller 130 executes the ink amount calculation process (S12) when the cartridge 200 is installed (S11: Yes), and executes the ink consumption operation and the ink amount calculation process (S18) when the ink is consumed when an ink consumption instruction is input (S15, S16: Yes). In the contract mode, the controller 130 executes the ink amount calculation process when the cartridge is installed in addition to the ink amount calculation process when the cartridge is installed in response to the installation of the cartridge, and executes the subtank remaining amount calculation process when the ink is consumed (S20) in addition to the ink consumption operation and the ink amount calculation process when the ink is consumed in response to the input of an ink consumption instruction.

[0099] [Ink volume calculation process when cartridge is installed] The ink amount calculation process (S12 in FIG. 9) when a cartridge is installed will be described in detail with reference to FIG. 10. The controller 130 first selects an unprocessed color from among the four colors (black, yellow, cyan, and magenta) and designates the selected color as i (S31). An unprocessed color is a color that has not yet been selected, that is, a color that has not yet been the subject of subsequent processing. i is one of k (black), y (yellow), c (cyan), and m (magenta).

[0100] Next, the controller 130 determines whether the attachment signal for color i has changed from high level to low level (S32). The attachment signal for color i changes from high level to low level when the cartridge 200 of color i is attached to the attachment case 150. If the controller 130 determines that the attachment signal for color i has changed from high level to low level (S32: Yes), the controller 130 proceeds to S33. If the controller 130 determines that the attachment signal for color i has not changed from high level to low level (S32: No), the controller 130 proceeds to S37 without executing S33 to S36.

[0101] In S33, the controller 130 reads the ink amount Vci and cartridge attribute information from the cartridge storage unit for color i through the contact 152, and writes the read cartridge attribute information to the EEPROM 134. As a result, the cartridge attribute information is updated with the cartridge attribute information stored in the cartridge storage unit for color i.

[0102] Next, the controller 130 calculates the total amount Vti of ink of color i after the cartridge 200 of color i is installed (S34). More specifically, the controller 130 calculates the total amount Vti of ink of color i by adding the ink amount Vci read from the cartridge memory unit of color i in S33 and the ink amount Vsi stored in EEPROM 134. That is, the controller 130 calculates the total amount Vti of ink of color i according to the following equation (1). Vti = Vci + Vsi … (1)

[0103] Next, the controller 130 obtains the ink amounts Vci and Vsi based on the total amount Vti of ink of color i calculated in S34 and the function F1i or function F2i (S35). More specifically, the controller 130 determines whether the total amount Vti of ink of color i is equal to or greater than the threshold value Vhi. If the total amount Vti is equal to or greater than the threshold value Vhi, the controller 130 obtains the ink amount Vsi from the total amount Vti using the function F1i. If the total amount Vti is less than the threshold value Vhi, the controller 130 obtains the ink amount Vsi from the total amount Vti using the function F2i. The controller 130 calculates the ink amount Vci by subtracting the ink amount Vsi from the total amount Vti.

[0104] Next, the controller 130 writes the ink amount Vci acquired in S35 to the cartridge storage unit for color i (S36). As a result, the ink amount Vci stored in the cartridge storage unit for color i is updated to the ink amount Vci calculated in S35.

[0105] Next, the controller 130 determines whether there is an unprocessed color among the four colors (S37). If the controller 130 determines that there is an unprocessed color (S37: Yes), it proceeds to S31. If the controller 130 determines that there is no unprocessed color (i.e., all colors have been processed) (S37: No), it ends the ink amount calculation process when the cartridge is installed and returns to immediately after S12 (FIG. 9).

[0106] [Ink consumption operations and ink volume calculation process during ink consumption operations] The ink consumption operation and the ink amount calculation process during the ink consumption operation (S18 in FIG. 9) will be described in detail with reference to FIG. 11. The controller 130 first acquires four liquid level signals output from the four liquid level sensors 155 (S41). The liquid level signals acquired in S41 are those before the ink consumption operation. The controller 130 writes information indicating whether the four liquid level signals are at a high level or a low level into the RAM 133 as first liquid level information.

[0107] Next, the controller 130 executes an ink consumption operation (S42). In S42, the controller 130 executes an operation to print an image on one sheet, for example. More specifically, the controller 130 causes the feed roller 23 and the conveyance roller 25 to convey the sheet on the feed tray 15, causes the head 21 to eject ink, and causes the discharge roller 27 to discharge the sheet on which the image has been recorded onto the discharge tray 16. In S42, the controller 130 may also execute an operation that consumes ink other than for printing (for example, a purging operation).

[0108] Next, the controller 130 again acquires the four liquid level signals output from the four liquid level sensors 155 (S43). The liquid level signals acquired in S43 are those after the ink consumption operation. The controller 130 writes information indicating whether the four liquid level signals are at a high level or a low level into the RAM 133 as second liquid level information.

[0109] Next, the controller 130 selects an unprocessed color from the four colors and designates the selected color as i (S44). Next, the controller 130 determines the liquid level signal of color i based on the first liquid level information and the second liquid level information (S45). If the controller 130 determines that the liquid level signals of color i acquired in S41 and S43 are both low level (S45: remains low), the controller 130 proceeds to S46. If the controller 130 determines that the liquid level signal of color i acquired in S41 is low level and the liquid level signal of color i acquired in S43 is high level (S45: changes from low to high), the controller 130 proceeds to S50. If the controller 130 determines that the liquid level signals of color i acquired in S41 and S43 are both high level (S45: remains high), the controller 130 proceeds to S52.

[0110] The controller 130 reaches S46 when the liquid level in the liquid chamber 210 of the cartridge 200 of color i is higher than a predetermined position P, whether before or after the ink consumption operation (S42). In S46, the controller 130 updates the count value TNi. More specifically, the controller 130 adds to the count value TNi a value equivalent to the amount of ink of color i that was instructed to be discharged in S42.

[0111] Next, the controller 130 calculates the total ink amount Vti of color i after the ink consuming operation has been executed (S47). More specifically, the controller 130 calculates the total ink amount Vti of color i by adding the ink amount Vci and the ink amount Vsi, and subtracting the ink amount corresponding to the count value TNi from the result. That is, the controller 130 calculates the total ink amount Vti of color i using the following equation (2): Vti = Vci + Vsi - TNi … (2)

[0112] Next, the controller 130 obtains the ink amounts Vci and Vsi based on the total ink amount Vti of color i calculated in S47 and the function F1i or function F2i (S48). Next, the controller 130 writes the ink amount Vci obtained in S48 to the cartridge memory unit for color i (S49) and proceeds to S54. In S48, the controller 130 performs the same process as in S35, and in S49, the controller 130 performs the same process as in S36.

[0113] The controller 130 reaches S50 when the liquid level in the liquid chamber 171 of the subtank 160 of color i falls below a predetermined position P during the processing of S42. In S50, the controller 130 sets the ink amount Vci to 0 and updates the ink amount Vsi with the ink amount Vai read from ROM 132. Next, the controller 130 writes the ink amount Vci to the cartridge memory unit of color i (S51). As a result, the ink amount Vci stored in the cartridge memory unit of color i is updated to 0. After executing S51, the controller 130 proceeds to S52.

[0114] If the liquid level in the liquid chamber 210 of the cartridge 200 of color i is lower than the predetermined position P before and after the ink consumption operation (S42), the controller 130 proceeds to S52 without executing S50 and S51. In S52, the controller 130 updates the count value SNi. More specifically, the controller 130 adds a value equivalent to the amount of ink of color i that was instructed to be discharged in S42 to the count value SNi.

[0115] Next, the controller 130 calculates the ink amount Vsi (S53). More specifically, the controller 130 calculates the ink amount Vsi by subtracting the ink amount corresponding to the count value SNi from the ink amount Vai read out from the ROM 132. That is, the controller 130 updates the ink amount Vsi in accordance with the following equation (3). Vsi = Vai - Sni … (3) Note that from the time the controller 130 executes S50 until the next time it executes S48, the ink amount Vci is 0, and the total ink amount Vti of color i is equal to the ink amount Vsi. After executing S53, the controller 130 proceeds to S54.

[0116] In S54, the controller 130 determines whether there is an unprocessed color among the four colors. If the controller determines that there is an unprocessed color (S54: Yes), the controller proceeds to S44. If the controller determines that there is no unprocessed color (i.e., all colors have been processed) (S54: No), the controller 130 ends the ink consumption operation and the ink amount calculation process when ink is consumed, and returns to immediately after S18 (FIG. 9).

[0117] [Subtank remaining capacity calculation process when cartridge is installed] The subtank remaining amount calculation process (S14 in FIG. 9) when the cartridge is installed will be described in detail with reference to Fig. 12. First, the controller 130 selects an unprocessed color from among the four colors, and sets the selected color as i (S111).

[0118] Next, the controller 130 calculates the ink change amount Pi of the subtank 160 of color i. More specifically, the controller 130 calculates the ink change amount Pi by subtracting the ink amount Vsi' (the ink amount Vsi the previous time the subtank remaining amount calculation process was executed) from the ink amount Vsi (S112). That is, the controller 130 calculates the ink change amount Pi according to the following equation (4). Pi = Vsi - Vsi' ... (4) Furthermore, in S112, the controller 130 updates the ink amount Vsi' with the ink amount Vsi.

[0119] Next, the controller 130 determines the type of the cartridge 200 of color i (S113). More specifically, the controller 130 determines the type of the cartridge 200 of color i based on the attribute information of the cartridge 200 of color i. If the controller 130 determines that the cartridge is a contract cartridge (S113: contract cartridge), the process proceeds to S114, and if the controller 130 determines that the cartridge is a commercially available cartridge (S113: commercially available cartridge), the process proceeds to S117.

[0120] In S114, the controller 130 determines whether the sum (SKi+Pi) of the ink amount SKi and the ink change amount Pi is greater than or equal to 0. More specifically, the controller 130 adds the ink amount SKi and the ink change amount Pi calculated in S112, and determines whether the result is greater than or equal to 0. If the controller 130 determines that the sum is greater than or equal to 0 (S114: Yes), it proceeds to S115, and if it determines that the sum is not greater than or equal to 0 (i.e., less than 0) (S114: No), it proceeds to S116.

[0121] In S115, the controller 130 adds the ink amount change Pi calculated in S112 to the ink amount SKi. That is, the controller 130 updates the ink amount SKi according to the following equation (5). SKi = SKi + Pi …(5)

[0122] In S116, the controller 130 adds the ink amount SKi and the ink change amount Pi to the ink amount SSi, and sets the ink amount SKi to 0. More specifically, the controller 130 adds the ink amount SKi and the ink change amount Pi calculated in S112 to the ink amount SSi. In other words, the controller 130 updates the ink amount SSi in accordance with the following equation (6). SSi = SSi + SKi + Pi … (6)

[0123] In S117, the controller 130 determines whether the sum (SSi+Pi) of the ink amount SSi and the ink change amount Pi is greater than or equal to 0. More specifically, the controller 130 adds the ink amount SSi and the ink change amount Pi calculated in S112, and determines whether the result is greater than or equal to 0. If the controller 130 determines that the sum is greater than or equal to 0 (S117: Yes), it proceeds to S118, and if it determines that the sum is not greater than or equal to 0 (i.e., less than 0) (S117: No), it proceeds to S119.

[0124] In S118, the controller 130 adds the ink amount change Pi calculated in S112 to the ink amount SSi. That is, the controller 130 updates the ink amount SSi according to the following equation (7). SSi = SSi + Pi … (7)

[0125] In S119, the controller 130 adds the ink amount SSi and the ink change amount Pi to the ink amount SKi, and sets the ink amount SSi to 0. More specifically, the controller 130 adds the ink amount SSi and the ink change amount Pi calculated in S112 to the ink amount SKi. In other words, the controller 130 updates the ink amount SKi in accordance with the following equation (8). SKi=SKi+SSi+Pi …(8)

[0126] The controller 130 reaches S120 after executing any one of S115, S116, S118, and S119. Next, the controller 130 determines whether there is an unprocessed color among the four colors (S120). If the controller 130 determines that there is an unprocessed color (S120: Yes), the controller 130 proceeds to S111. If the controller 130 determines that there is no unprocessed color (i.e., all four colors have been processed) (S120: No), the controller 130 ends the subtank remaining amount calculation process when the cartridge is installed, and returns to immediately after S14 (FIG. 9).

[0127] In many cases, an unused cartridge 200 is mounted in the mounting case 150. At this time, the amount of ink stored in the liquid chamber 171 of the subtank 160 increases. For this reason, in many cases, the ink change amount Pi calculated in S112 will be equal to or greater than 0. Therefore, in many cases, the controller 130 only needs to add the ink change amount Pi to the ink amount SKi or SSi depending on the type of cartridge 200 in the subtank remaining amount calculation process when the cartridge is mounted (S115, S118).

[0128] However, there are cases where a new cartridge 200 is mounted in the mounting case 150 when the ink level stored in the liquid chamber 171 of the subtank 160 is above the predetermined position P. In this case, ink may flow back from the subtank 160 to the cartridge 200, causing the ink amount SKi calculated in S115 or the ink amount SSi calculated in S118 to become negative. In reality, the ink amounts SKi and SSi never become negative. Therefore, in the subtank remaining amount calculation process when a contract cartridge is mounted and the ink amount SKi calculated in S115 becomes negative, the controller 130 sets the ink amount SKi to 0 and updates the ink amount SSi according to equation (6) (S116). If a commercially available cartridge is mounted and the ink amount SSi calculated in S118 becomes negative, the controller 130 sets the ink amount SSi to 0 and updates the ink amount SKi according to equation (8) (S118).

[0129] In this way, the controller 130, in response to determining that the contract cartridge is attached to the mounting case 150 in the contract mode, acquires the ink amount Vsi in S35 based on the ink amount Vci read from the cartridge storage unit of the cartridge 200 in S33, calculates the ink change amount Pi in S112, and updates the ink amount SKi in S115 or S116. In other words, in response to determining that the contract cartridge is attached to the mounting case 150 in the contract mode, the controller 130 updates the ink amount SKi based on the ink amount Vci acquired from the contract cartridge.

[0130] Furthermore, the controller 130 is in contract mode, and in response to determining that a commercially available cartridge has been attached to the mounting case 150, the controller 130 acquires the ink amount Vsi in S35 based on the ink amount Vci read from the cartridge memory unit of the cartridge 200 in S33, calculates the ink change amount Pi in S112, and updates the ink amount SSi in S117 or S118. In other words, in response to determining that the controller 130 is in contract mode, and in response to determining that a commercially available cartridge has been attached to the mounting case 150, the controller 130 updates the ink amount SSi based on the ink amount Vci acquired from the commercially available cartridge. Therefore, in response to the attachment of the cartridge 200, the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, SSm can be updated.

[0131] [Subtank remaining amount calculation process when ink is consumed] The subtank remaining amount calculation process when ink is consumed (S20 in FIG. 9) will be described in detail with reference to Figure 13. The controller 130 first selects an unprocessed color from among the four colors, and sets the selected color as i (S131).

[0132] Next, the controller 130 determines the ink consumption amount Qi of color i and the ink change amount Ri of the cartridge 200 of color i (S132). More specifically, the controller 130 determines the ink consumption amount Qi by subtracting the sum of the ink amounts Vci and Vsi (Vci+Vsi) from the sum of the ink amounts Vci' and Vsi' (Vci'+Vsi'). The controller 130 determines the ink change amount Ri by subtracting the ink amount Vci from the ink amount Vci'. That is, the controller 130 calculates the ink consumption amount Qi according to the following equation (9), and determines the ink change amount Ri according to the following equation (10). Qi=(Vci'+Vsi')-(Vci+Vsi) …(9) Ri=Vci'-Vci …(10) Furthermore, in S132, the controller 130 updates the ink amounts Vci' and Vsi' with the ink amounts Vci and Vsi, respectively.

[0133] Next, the controller 130 determines the type of cartridge 200 of color i (S133). In S133, the controller 130 performs the same process as in S113 (FIG. 12). If the controller 130 determines that the cartridge is a contract cartridge (S133: contract cartridge), the process proceeds to S134, and if the controller 130 determines that the cartridge is a commercially available cartridge (S133: commercially available cartridge), the process proceeds to S135.

[0134] In S134, the controller 130 adds the ink amount change Ri calculated in S132 to the ink amount SKi. That is, the controller 130 updates the ink amount SKi according to the following equation (11). SKi = SKi + Ri …(11)

[0135] In S135, the controller 130 adds the ink amount change Ri calculated in S132 to the ink amount SSi. That is, the controller 130 updates the ink amount SSi according to the following equation (12). SSi = SSi + Ri … (12)

[0136] After executing S134 or S135, the controller 130 reaches S136. Next, the controller 130 determines whether the ink amount SSi is equal to or greater than the ink consumption amount Qi calculated in S132 (S136). If the controller 130 determines that the ink amount SSi is equal to or greater than the ink consumption amount Qi (S136: Yes), it proceeds to S137, and if the controller 130 determines that the ink amount SSi is not equal to or greater than the ink consumption amount Qi (i.e., the ink amount SSi is less than the ink consumption amount Qi) (S136: No), it proceeds to S138.

[0137] In S137, the controller 130 subtracts the ink consumption amount Qi found in S132 from the ink amount SSi, and sets the flag FLAGi for color i to OFF. That is, the controller 130 updates the ink amount SSi according to the following equation (13). SSi=SSi-Qi …(13)

[0138] In S138, the controller 130 subtracts the difference (Qi-SSi) between the ink consumption amount Qi calculated in S132 and the ink amount SSi from the ink amount SKi, sets the ink amount SSi to 0, and sets the flag FLAGi for color i to ON. In other words, the controller 130 updates the ink amount SKi according to the following equation (14). SKi = SKi - (Qi - SSi) ... (14)

[0139] After executing S137 or S138, the controller 130 reaches S139. Next, the controller 130 determines whether there is an unprocessed color among the four colors (S139). If the controller 130 determines that there is an unprocessed color (S139: Yes), the controller 130 proceeds to S131. If the controller 130 determines that there is no unprocessed color (i.e., all four colors have been processed) (S139: No), the controller 130 proceeds to S140.

[0140] In S140, the controller 130 determines whether the ink consumption instruction determined in S16 (FIG. 9) is an instruction for which charges are to be made. For example, normal print instructions are included in instructions for which charges are to be made, but print instructions and purge instructions for managing the printer 10 are not included in instructions for which charges are to be made. If the controller 130 determines that the instruction is a chargeable instruction (S140: Yes), the controller 130 proceeds to S141.

[0141] When the controller 130 reaches S141, four flags FLAGk, FLAGy, FLAGc, and FLAGm are set to ON or OFF. In S141, the controller 130 determines whether any of the four flags is ON. If the controller 130 determines that any of the four flags is ON (S141: Yes), the controller 130 proceeds to S142. In this case, the controller 130 sets the billing flag to ON (S142).

[0142] If the controller 130 determines in S140 that the content is not subject to billing (S140: No), or if the controller 130 determines in S141 that all of the four flags are OFF (S141: No), the controller 130 proceeds to S143. In this case, the controller 130 sets the billing flag to OFF (S143).

[0143] After executing S142 or S143, the controller 130 ends the subtank remaining amount calculation process when ink is consumed, and returns to immediately after S20 (FIG. 9).

[0144] In S132, the controller 130 calculates the ink consumption amount Qi of color i and the ink change amount Ri of the cartridge 200 of color i. The ink consumption amount Qi is a positive value. The ink change amount Ri is equal to the amount of ink flowing into the subtank 160 of color i. In the subtank remaining amount calculation process when ink is consumed, the controller 130 adds the ink change amount Ri to the ink amount SKi or SSi depending on the type of cartridge 200 (S135, S135).

[0145] In S136, the controller 130 determines whether the ink amount SSi is equal to or greater than the ink consumption amount Qi (in other words, whether the ink supplied from the commercially available cartridge of color i and stored in the subtank 160 of color i can cover the current ink consumption). In this embodiment, if the current ink consumption can be covered, only the ink supplied from the commercially available cartridge of color i and stored in the subtank 160 of color i is consumed, and if the current ink consumption cannot be covered, all of the ink supplied from the commercially available cartridge of color i and stored in the subtank 160 of color i is consumed, and the ink supplied from the contract cartridge of color i and stored in the subtank 160 of color i is consumed to make up the shortfall.

[0146] If the current ink consumption can be covered (S136: Yes), the controller 130 subtracts the ink consumption amount Qi from the ink amount SSi (S137). The user has already paid for the ink consumed this time (ink supplied from a commercially available cartridge). Therefore, the controller 130 sets the flag FLAGi for color i to OFF (no charge).

[0147] If the current ink consumption is not covered (S136: No), the controller 130 sets the ink amount SSi to 0 and subtracts the shortage ink amount (Qi-SSi) from the ink amount SKi (S138). The ink consumed this time includes ink supplied from the contract cartridge. Therefore, the controller 130 sets the flag FLAGi of color i to ON (charged).

[0148] The controller 130 sets the billing flag to ON (billing) when it determines that the instruction is for billing and that the ink supplied from the contract cartridge for any of the four colors has been consumed (S140, S141: Yes). The controller 130 sets the billing flag to ON when it determines that the ink supplied from the contract cartridge for any of the colors has been consumed in the subtank remaining amount calculation process when ink is consumed.

[0149] In this way, the controller 130, in the contract mode, executes the following process in response to receiving an ink consumption instruction. When the controller 130 determines that a contract cartridge is attached to the mounting case 150 of color i (S133: contract cartridge), it adds the amount of change in the amount of ink stored in the contract cartridge (ink change amount Ri) to the ink amount SKi (S134). When the controller 130 determines that a commercially available cartridge is attached to the mounting case 150 of color i (S133: commercially available cartridge), it adds the amount of change in the amount of ink stored in the commercially available cartridge (ink change amount Ri) to the ink amount SSi (S135). The controller 130 calculates the ink consumption amount Qi, which is the sum of the amount of change in the amount of ink stored in the cartridge 200 of color i attached to the mounting case 150 of color i (Vci-Vci') and the amount of change in the amount of ink stored in the subtank 160 of color i (Vsi-Vsi') (S132). If the ink amount SSi is equal to or greater than the ink consumption amount Qi (S136: Yes), the controller 130 subtracts the ink consumption amount Qi from the ink amount SSi (S137). If the ink amount SSi is less than the ink consumption amount Qi (S136: No), the controller 130 subtracts the difference between the ink consumption amount Qi and the ink amount SSi (Qi-SSi) from the ink amount SSi, and updates the ink amount SSi to 0 (S138). Therefore, the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, SSm can be updated in response to the controller 130 performing an operation to eject ink from the nozzles 29. The above five processes are examples of update processes.

[0150] In the above update process, if the ink amount SSi is equal to or greater than the ink consumption amount Qi (S136: Yes), the controller 130 sets the flag FLAGi for color i to OFF (S137), and if the ink amount SSi is less than the ink consumption amount Qi (S136: No), the controller 130 sets the flag FLAGi for color i to ON. Therefore, the billing flag can be set in response to the controller 130 performing an operation to eject ink from the nozzles 29. Note that the value ON set for the flag FLAGi and the billing flag is an example of a first value. The value OFF set for the flag FLAGi and the billing flag is an example of a second value.

[0151] [Operations of the controller 130 other than those mentioned above] As described above, in the contract mode, the controller 130 separately stores in the EEPROM 134 the amount of ink SKi supplied from the contract cartridge of color i and stored in the subtank 160 of color i when the contract cartridge of color i is attached to the mounting case 150 of color i, and the amount of ink SSi supplied from the commercially available cartridge of color i and stored in the subtank 160 of color i when the commercially available cartridge of color i is attached to the mounting case 150 of color i. In the non-contract mode, the controller 130 combines the ink amount SKi and the ink amount SSi and stores them as a single amount in the EEPROM 134. This simplifies the processing of the controller 130 in the non-contract mode.

[0152] [Billing Server 300] 7, the billing server 300 includes a CPU 301, a RAM 302, a storage unit 303, and a communication interface 304. The communication interface 304 is an interface for communicating with the printer 10. The billing server 300 controls the communication interface 304 to communicate with the printer 10 and the like via a communication network 350. The communication network 350 may be, for example, a communication network including the Internet, or a communication network including a telephone line or a dedicated line. The billing server 300 is an example of a server.

[0153] Storage unit 303 stores billing information for multiple printers connected to billing server 300 via communication network 350. For example, storage unit 303 stores the contract number and the number of prints associated with each other for printer 10 under contract with the user.

[0154] As described above, in S22 (FIG. 9), the controller 130 of the printer 10 sends a billing instruction to the billing server 300. The billing instruction includes the contract number and information indicating that one sheet has been printed. The billing instruction may also include information indicating the printing date and time, the size and type of sheet, etc.

[0155] When CPU 301 of billing server 300 receives a billing instruction from printer 10 via communication interface 304, it acquires the contract number from the received billing instruction. CPU 301 adds a value of 1 to the number of printed sheets stored in memory unit 303 that corresponds to the acquired contract number. In this way, CPU 301 determines the number of printed sheets used by printer 10 under contract with the user. The administrator of billing server 300 requests payment from the user of printer 10 according to the number of printed sheets in a specified period (e.g., one month). For example, if the number of printed sheets in the specified period exceeds the contracted number, the administrator of billing server 300 requests payment from the user of printer 10 according to the number of printed sheets exceeding the contracted number.

[0156] The billing instruction sent from printer 10 to billing server 300 is an instruction that triggers billing processing in billing server 300. When billing server 300 receives a billing instruction, it does not necessarily bill the user of printer 10, but it may simply execute some processing related to billing for the user of printer 10 when it receives a billing instruction.

[0157] The controller 130 of the printer 10 displays the execution of billing on the display 17 and transmits a billing instruction to the billing server 300. In response to the transmission of the billing instruction by the controller 130 of the printer 10, the billing server 300 updates the number of prints corresponding to the contract number included in the received billing instruction. The display of the execution of billing and the transmission of the billing instruction performed by the controller 130 of the printer 10 are an example of a first billing process. The update of the number of prints performed by the billing server 300 is an example of a second billing process.

[0158] [Effects of the embodiment] In the printer 10 according to the above embodiment, in the contract mode, the controller 130 stores in the EEPROM 134 the ink amounts SKk, SKy, SKc, and SKm supplied from the contract cartridge and stored in the subtank 160 when a contract cartridge is attached to the attachment case 150, and the ink amounts SSk, SSy, SSc, and SSm supplied from the commercially available cartridge and stored in the subtank 160 when a commercially available cartridge is attached to the attachment case 150. Therefore, by performing billing processing based on these ink amounts, it is possible to prevent a user from being disadvantaged when replacing a cartridge while ink remains in the subtank 160. In particular, in a printer 10 in which the liquid level of the cartridge 200 and the liquid level of the subtank 160 are aligned, it is possible to prevent a user from being disadvantaged when replacing the cartridge 200 while ink remains in the tank.

[0159] If the billing flag is ON after the update process is performed, the controller 130 transmits a billing instruction to the billing server 300. Therefore, whether or not to perform the billing process can be switched depending on the value of the billing flag. The printer 10 also includes multiple mounting cases 150, each of which can accommodate cartridges 200 corresponding to one of multiple colors, and the EEPROM 134 stores four flags corresponding to the four colors. The controller 130 performs the update process for each of the cartridges 200 mounted in the multiple mounting cases 150, and if at least one of the four flags is ON after the update process is performed, the controller 130 transmits a billing instruction to the billing server 300. Therefore, in a printer 10 that can accommodate multiple cartridges, whether or not to perform the billing process can be switched depending on the value of the billing flag.

[0160] Printer 10 is equipped with a display 17 that notifies the user that charging is being performed, and controller 130 causes display 17 to notify the user that charging is being performed during charging processing. Therefore, the user can be notified that charging is being performed. Printer 10 is also equipped with a communication interface 140, and controller 130 transmits an instruction to perform charging to charging server 300 via communication interface 140 during charging processing. Therefore, the instruction to perform charging can be given to charging server 300 connected to printer 10.

[0161] According to the accounting flag set by the printer 10, the controller 130 of the printer 10 sends an accounting instruction, and the accounting server 300 updates the number of printed sheets, so that the printer 10 and the accounting server 300 can share the accounting process.

[0162] [Variations] In the above embodiment, as an example, a printer 10 capable of mounting cartridges 200 of multiple colors and having multiple sub-tanks 160 was described, but a printer according to a modified example may also be capable of mounting cartridges of one color and have a sub-tank of one color.

[0163] In the above embodiment, the controller 130 of the printer 10 performs the ink amount calculation process shown in Figures 10 and 11 to determine the ink amount Vci stored in the liquid chamber 210 of the cartridge 200 of color i and the ink amount Vsi stored in the liquid chamber 171 of the subtank 160 of color i. Alternatively, the controller 130 may perform a process other than the ink amount calculation process shown in Figures 10 and 11 to determine the ink amounts Vci and Vski. For example, the controller 130 may determine the ink amount Vsi from the total ink amount Vti of color i based on a single function rather than two functions. Alternatively, the controller 130 may determine the ink amount Vci from the total ink amount Vti based on a function that indicates the relationship between the total ink amount Vti and the ink amount Vci of color i, and then determine the ink amount Vsi by subtracting the ink amount Vci from the total ink amount Vti.

[0164] In the above embodiment, the controller 130 executes a first billing process by displaying billing execution and transmitting a billing instruction, and the billing server 300 executes a second billing process by updating the number of printed sheets. Alternatively, the controller 130 may execute a first billing process other than the above, and the billing server 300 may execute a second billing process other than the above. For example, instead of displaying the billing execution on the display 17, the controller 130 may notify the user of the billing execution by sound or by lighting a lamp. Furthermore, the controller 130 may transmit a billing instruction including the printing date and time, the sheet size and type, etc. Upon receiving such a billing instruction, the billing server 300 may update the number of printed sheets for each sheet size and type.

[0165] In the above embodiment, the controller 130 stores the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, and SSm in the EEPROM 134 and determines whether or not to charge. Alternatively, the controller 130 stores the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, and SSm in the EEPROM 134, but may transmit the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, and SSm to the billing server 300 in response to a request from the billing server 300 (or at predetermined time intervals) without determining whether or not to charge. In this modified example, the billing server 300 determines whether or not to charge based on the ink amounts SKk, SKy, SKc, SKm and the ink amounts SSk, SSy, SSc, and SSm received from the printer 10.

[0166] In the above embodiment, the controller 130 immediately stores the acquired or calculated data in the EEPROM 134. Alternatively, the controller 130 may store acquired or calculated data that does not need to be stored when the printer 10 is powered off in the RAM 133. The controller 130 may also temporarily store acquired or calculated data in the RAM 133, and then store the data read from the RAM 133 in the EEPROM 134 when the printer 10 is powered off.

[0167] In the above embodiment, the controller 130 stores the ink amounts SKi and SSi in memory (specifically, writes them to the EEPROM 134) when the cartridge 200 is attached (S115, S116, S118, and S119 in FIG. 12) and when ink is consumed (S134, S135, S137, and S138 in FIG. 13). The controller 130 may store the ink amounts SKi and SSi in memory at timing other than the above. For example, the controller 130 may store the ink amounts SKi and SSi in memory at timing when the liquid level signal output from the liquid level sensor 155 changes from low level to high level as the ink volatilizes. [Explanation of symbols]

[0168] 10. Printer (image recording device) 17. Display (notification unit) 21...head 29 Nozzle 130 Controller 132···ROM (memory) 133 RAM (memory) 134···EEPROM (memory) 140 Communication Interface 150···Attachment case (attachment part) 160···Subtank (tank) 200 Cartridges (1st Cartridge, 2nd Cartridge) 300: Billing server (server) SKk, SKy, SKc, SKm... Ink amount (1st tank liquid amount) SSk, SSy, SSc, SSm... Ink amount (second tank liquid amount)

Claims

1. a mounting portion into which a first cartridge or a second cartridge for storing a liquid can be mounted; a tank that stores the liquid supplied from the first cartridge or the second cartridge attached to the attachment portion; a head connected to the tank and having a nozzle for discharging the liquid; Memory and Equipped with a controller, The first cartridge is a contract cartridge that is used under a service contract and is free of charge under the conditions specified in the service, and the second cartridge is a commercially available cartridge, The above controller is The device is capable of transitioning between a first operating state in which the service is subscribed to and a second operating state in which the service is not subscribed to, in the first operating state, a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is attached to the attachment portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is attached to the attachment portion, are stored in the memory; in the first operating state, in response to receiving an instruction to eject liquid from the nozzle, updating the first tank liquid amount and the second tank liquid amount, and setting a billing flag to either a first value or a second value based on the second tank liquid amount; An image recording device that executes a billing process when the billing flag has the first value, and does not execute the billing process when the billing flag has the second value.

2. The above controller is determining the type of the cartridge attached to the attachment portion in accordance with a signal acquired from the first cartridge or the second cartridge attached to the attachment portion; updating the first tank liquid amount based on information acquired from the first cartridge in response to determining that the first operating state is in the first operating state and that the first cartridge has been attached to the attachment portion; The image recording device according to claim 1, wherein when the device is in the first operating state and it is determined that the second cartridge has been mounted in the mounting portion, the liquid amount in the second tank is updated based on information obtained from the second cartridge.

3. the controller is in the first operating state and executes an update process in response to receiving an instruction to eject the liquid from the nozzle; In the update process, the controller adding a change in the amount of liquid stored in the first cartridge to the first tank liquid amount in response to determining that the first cartridge is attached to the attachment portion; adding a change in the amount of liquid stored in the second cartridge to the second tank liquid amount in response to determining that the second cartridge is attached to the attachment portion; calculating a consumption amount, which is the sum of the amount of change in the amount of liquid stored in the cartridge attached to the attachment portion and the amount of change in the amount of liquid stored in the tank; If the second tank liquid amount is equal to or greater than the consumption amount, subtract the consumption amount from the second tank liquid amount; 3. The image recording device according to claim 2, wherein when the second tank liquid amount is less than the consumption amount, the difference between the consumption amount and the second tank liquid amount is subtracted from the first tank liquid amount, and the second tank liquid amount is updated to zero.

4. The memory stores a flag, In the update process, the controller setting the flag to the second value when the second tank liquid amount is equal to or greater than the consumption amount; setting the flag to the first value in response to the second tank liquid amount being less than the consumption amount; 4. The image recording device according to claim 3, wherein the controller, when the flag is the first value after the update process is executed, determines that the accounting flag is the first value and executes the accounting process.

5. a plurality of the mounting portions are provided, and a cartridge corresponding to one of a plurality of colors can be mounted in each of the mounting portions; the memory stores a plurality of flags corresponding to the plurality of colors; The above controller is The update process is performed for each of the cartridges mounted in the plurality of mounting portions, 5. The image recording device according to claim 4, wherein, after the update process is executed, if at least one of the plurality of flags is the first value, the accounting flag is set to the first value and the accounting process is executed.

6. A notification unit is further provided to notify the execution of billing, 6. The image recording device according to claim 4, wherein the controller operates the notification unit in the charging process.

7. further comprising a communication interface for communicating with the server; 7. The image recording apparatus according to claim 4, wherein the controller transmits an instruction to execute accounting to the server through the communication interface in the accounting process.

8. 8. The image recording device according to claim 1, wherein the controller stores the first tank liquid amount and the second tank liquid amount together as one amount in the memory in the second operating state.

9. 9. The image recording device according to claim 1, wherein the height of the liquid surface stored in the cartridge attached to the attachment portion is equal to the height of the liquid surface stored in the tank.

10. an image recording device; a server connected to the image recording device, The image recording device is a mounting portion into which a first cartridge or a second cartridge for storing a liquid can be mounted; a tank that stores the liquid supplied from the first cartridge or the second cartridge attached to the attachment portion; a head connected to the tank and having a nozzle for discharging the liquid; Memory and Equipped with a controller, The first cartridge is a contract cartridge that is used under a service contract and is free of charge under the conditions specified in the service, and the second cartridge is a commercially available cartridge, The above controller is The device is capable of transitioning between a first operating state in which the service is subscribed to and a second operating state in which the service is not subscribed to, in the first operating state, a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is attached to the attachment portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is attached to the attachment portion, are stored in the memory; in the first operating state, in response to receiving an instruction to eject liquid from the nozzle, updating the first tank liquid amount and the second tank liquid amount, and setting a billing flag to either a first value or a second value based on the second tank liquid amount; executes a first accounting process when the accounting flag is the first value, and does not execute the first accounting process when the accounting flag is the second value; The server executes a second billing process in response to the controller executing the first billing process.

11. A billing method using an image recording device and a server connected to the image recording device, comprising: The image recording device is a mounting portion into which a first cartridge or a second cartridge for storing a liquid can be mounted; a tank that stores the liquid supplied from the first cartridge or the second cartridge attached to the attachment portion; a head connected to the tank and having a nozzle for discharging the liquid; Memory and Equipped with a controller, The first cartridge is a contract cartridge that is used under a service contract and is free of charge under the conditions specified in the service, and the second cartridge is a commercially available cartridge, the controller is capable of transitioning between a first operating state in which the service is subscribed to and a second operating state in which the service is not subscribed to; a step in which the controller stores in the memory, in the first operating state, a first tank liquid amount, which is the amount of liquid supplied from the first cartridge and stored in the tank when the first cartridge is attached to the attachment portion, and a second tank liquid amount, which is the amount of liquid supplied from the second cartridge and stored in the tank when the second cartridge is attached to the attachment portion; updating the first tank liquid amount and the second tank liquid amount in response to receiving an instruction to eject liquid from the nozzle while the controller is in the first operating state, and setting a billing flag to either a first value or a second value based on the second tank liquid amount; a step of the controller executing a first accounting process in response to the accounting flag being the first value; and a step of the server executing a second accounting process in response to the controller executing the first accounting process, The accounting method in which the controller does not execute the first accounting process in response to the accounting flag having the second value.

Images