Liquid dispensing device

Abstract

To provide a liquid discharge device which can suppress adverse effects on a liquid discharge performance of a droplet discharge head or on a nozzle of the droplet discharge head.SOLUTION: A liquid discharge device comprises: a droplet discharge head having a plurality of nozzles for discharging liquid; a head tank for temporarily accommodating liquid to be supplied to the droplet discharge head; at least one liquid cartridge for accommodating liquid to be supplied to the head tank; a liquid detection part for detecting a remaining amount of the liquid in the liquid cartridge; a maintenance recovery mechanism for performing cleaning operation of discharging liquid from the plurality of nozzles of the droplet discharge head; and a notification part for issuing a perception signal to a user. (1) When a detected remaining amount of the liquid is not less than a predetermined amount, it goes into a state in which printing can be performed, and (2) when a detected remaining amount of the liquid is less than the predetermined amount, it goes into a state in which printing cannot be performed, issues notification that the liquid cartridge is empty or notification to urge replacement of the liquid cartridge, and makes cleaning operation executable.SELECTED DRAWING: Figure 10

Description

[Technical field]

[0001] The present invention relates to a liquid ejection device. [Background technology]

[0002] 2. Description of the Related Art Known image forming apparatuses, such as printers, facsimiles, copiers, plotters, and combination machines thereof, are image forming apparatuses (such as inkjet recording devices) that use a liquid ejection recording type image forming apparatus that uses a liquid ejection head (droplet ejection head) that ejects liquid droplets as a recording head.

[0003] Inkjet recording devices mainly use ink cartridges as a means for supplying the liquid (ink) to be ejected. Also, when the ink in the ink cartridge falls below a certain amount (empty), a message urging replacement is displayed on the built-in display (see, for example, Patent Document 1). Summary of the Invention [Problem to be solved by the invention]

[0004] By the way, heavy pigment ink settles quickly and is prone to clogging the nozzles of the recording head, so it is necessary to perform maintenance operations (such as blank ejection) frequently. However, when the ink runs out, blank ejection is not performed, which can cause damage to the nozzles.

[0005] SUMMARY OF THE PRESENT EMBODIMENTS Accordingly, an object of the present invention is to provide a liquid ejection device that can suppress adverse effects on the liquid ejection performance of a droplet ejection head (recording head) and on the nozzles of the droplet ejection head. [Means for solving the problem]

[0006] The above issues are: a droplet ejection head having a plurality of nozzles for ejecting liquid, a head tank for temporarily storing liquid to be supplied to the droplet ejection head, at least one liquid cartridge for storing liquid to be supplied to the head tank, a liquid detection unit for detecting a remaining amount of liquid in the liquid cartridge, a maintenance and recovery mechanism for performing a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head, and an alarm unit for issuing a sensory signal to a user, (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) A liquid ejection device that, when the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, renders itself into a state in which printing is not possible, and when in the state in which printing is not possible, issues a notification that the liquid cartridge is empty or a notification urging the user to replace the liquid cartridge, thereby enabling the cleaning operation to be performed, wherein the notification that the liquid cartridge is empty or the notification urging the user to replace the liquid cartridge when the detected remaining amount of liquid in the liquid cartridge is zero is the same as the notification that the liquid cartridge is empty or the notification urging the user to replace the liquid cartridge when the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount. is solved by: Effect of the Invention

[0007] When the amount of liquid remaining in the liquid cartridge is less than a predetermined amount, the liquid ejection device of the present invention enters a state in which printing is disabled, prompting the user to replace the liquid cartridge and enabling a cleaning operation to be performed, thereby suppressing adverse effects on the liquid ejection performance of the droplet ejection head and the nozzles of the droplet ejection head. [Brief description of the drawings]

[0008] [Figure 1] 1 is a perspective view of a liquid ejection apparatus (inkjet recording apparatus) according to an embodiment of the present invention, as viewed from the front. [Diagram 2] 2 is a side view showing an outline of a mechanism of the device shown in FIG. 1. [Diagram 3] 2 is a plan view of the main part of the mechanism of the device shown in FIG. 1. [Figure 4] 2 is an overall block diagram showing an example of a control unit of the device shown in FIG. 1. [Diagram 5] FIG. 2 is a perspective view showing a structure of a head tank according to an embodiment of the present invention. [Figure 6] 6 is a schematic diagram showing the discharge of ink from the head tank shown in FIG. 5. [Figure 7] FIG. 2 is a schematic diagram illustrating a configuration of an ink supply pipe according to an embodiment of the present invention. [Figure 8] FIG. 2 is a schematic diagram showing the configuration of a tube pump. [Figure 9] 5A to 5C are schematic diagrams illustrating changes in the liquid level in the head tank and film behavior. [Figure 10] 2 is a schematic diagram showing the configuration of an automatic maintenance mechanism in the device shown in FIG. 1. [Figure 11] FIG. 13 is a schematic diagram illustrating a state in which the white ink cartridge is left without being shaken. [Figure 12] 5A and 5B are schematic diagrams illustrating ink concentrations when the white ink cartridge is in use. [Figure 13] FIG. 4 is a schematic diagram showing a state in which ink has solidified in the nozzle portion of the recording head. [Figure 14]10 is a flowchart showing a cleaning operation for improving the nozzle condition. [Figure 15] 11 is a schematic diagram showing an example of a screen display displayed on a display of a notification unit. FIG. [Figure 16] 13 is a schematic diagram showing an example of a warning displayed on a display of a notification unit; FIG. [Figure 17] 13 is a flowchart showing a second cleaning operation for improving the nozzle condition without supplying ink. [Figure 18] FIG. 13 is a schematic diagram (part 1) showing an example of a screen display at the time of the first end, which is displayed on the display of the notification unit. [Figure 19] FIG. 2 is a schematic diagram (part 2) showing an example of a screen display at the first end, which is displayed on the display of the notification unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1 is a perspective view of a liquid ejection device (inkjet recording device) according to one embodiment of the present invention, as seen from the front. The inkjet recording device 100 comprises a device main body 1, a paper feed tray 2 for loading paper sheets attached to the device main body 1, and a paper output tray 3 that is detachably attached to the device main body 1 and for stocking paper sheets on which images have been recorded (formed).

[0010] Furthermore, a cartridge loading section 4 for loading an ink cartridge 10, which is a liquid cartridge, is provided adjacent to the paper feed / eject tray section on one side of the front surface of the device main body 1. An alarm section 5 for issuing a sensory signal to the user is provided on the upper surface of this cartridge loading section 4.

[0011] Ink cartridges 10 are set in the cartridge loading section 4. Each ink cartridge 10 contains a recording liquid (ink) of a different color, for example, black (K), cyan (C), magenta (M), yellow (Y), and white (W). These ink cartridges 10 can be loaded by inserting them from the front side of the device body 1 toward the rear side, and are configured to be loaded by lining up the ink cartridges 10 horizontally in a vertically placed state. A front cover (cartridge cover) 6 is provided on the front side of the cartridge loading section 4 in an openable and closable manner, which is opened when the ink cartridge 10 is attached or detached.

[0012] The notification unit 5 is composed of a display, a speaker, etc., and can display messages such as the remaining ink level of each ink cartridge 10 and issue warnings with a buzzer sound. In addition, below the notification unit 5, a power button 12, a paper feed / print resume button 13, and a cancel button 14 are also arranged.

[0013] Next, the mechanical section of the inkjet recording apparatus 100 will be described with reference to Figures 2 and 3. Figure 2 is a side view showing an outline of the mechanical section, and Figure 3 is a plan view of the essential parts of the same.

[0014] In the mechanical section of the inkjet recording device 100, a guide rod 31 and a stay 32, which are guide members, are horizontally supported on left and right side plates 21A and 21B constituting a frame 21, and these support a carriage 33 so as to be slidable in the main scanning direction. The carriage 33 is moved and scanned in the direction indicated by the arrow in FIG. 3 (the carriage main scanning direction) via a timing belt by a main scanning motor.

[0015] The inkjet recording apparatus 100 of this embodiment is a serial type image forming apparatus in which the recording head 34 ejects ink while moving in the main scanning direction to form an image.

[0016] A recording head 34 consisting of four droplet ejection heads that eject ink droplets of each color as described above is mounted on the carriage 33 with a plurality of ink ejection ports (a plurality of nozzles) arranged in a direction intersecting the main scanning direction (paper feed direction) and with the ink droplet ejection direction facing downward. Note that it is also possible to adopt a configuration of one or more heads having nozzle rows that eject droplets of each color.

[0017] As the inkjet head constituting the recording head 34, one having a piezoelectric actuator such as a piezoelectric element as pressure generating means for ejecting droplets can be used.

[0018] Further, the carriage 33 is equipped with head tanks 35 of each color for supplying ink of each color to each recording head 34. As described above, the head tanks 35 of each color are replenished with ink of each color from the ink cartridges 10 of each color mounted in the cartridge loading section 4 via ink supply tubes 36 of each color. The cartridge loading section 4 is provided with a liquid delivery pump 24, which is a liquid delivery means for delivering ink in the ink cartridges 10.

[0019] On the other hand, as a paper feed section for feeding the papers 42 loaded on the paper loading section (pressure plate) 41 of the paper feed tray 2, there is provided a half-moon roller (paper feed roller) 43 that separates and feeds the papers 42 one by one from the paper loading section 41, and a separation pad 44 facing the paper feed roller 43. The separation pad 44 is made of a material with a large coefficient of friction, and is biased towards the paper feed roller 43.

[0020] In order to feed the paper 42 fed from this paper feed section to the lower side of the recording head 34, a guide member 45 for guiding the paper 42, a counter roller 46, a transport guide member 47, and a pressing member 48 having a tip pressure roller 49 are provided. Furthermore, a transport belt 51 is provided as a transport means for electrostatically adsorbing the fed paper 42 and transporting it to a position facing the recording head 34.

[0021] The conveyor belt 51 is an endless belt that is stretched between a conveyor roller 52 and a tension roller 53 and configured to rotate in the belt conveying direction (sub-scanning direction). The conveyor belt 51 is also provided with a charging roller 56 that is a charging means for charging the surface of the conveyor belt 51. The charging roller 56 is arranged to come into contact with the surface layer of the conveyor belt 51 and to rotate following the rotation of the conveyor belt 51. Furthermore, a guide member 57 is arranged on the back side of the conveyor belt 51 in correspondence with the printing area by the recording head 34.

[0022] The conveyor belt 51 moves in a circular motion in the sub-scanning direction (belt conveying direction) indicated by an arrow in FIG. 3 as the conveyor roller 52 is rotated and driven by a sub-scanning motor via timing.

[0023] Furthermore, as a paper discharge section for discharging the paper 42 recorded by the recording head 34, a separation claw 61 for separating the paper 42 from the conveyor belt 51, a paper discharge roller 62, and a paper discharge roller 63 are provided. Below the paper discharge roller 62, a paper discharge tray 3 is provided.

[0024] A duplex unit 71 is detachably attached to the rear of the device body 1. This duplex unit 71 takes in the paper 42 returned by the reverse rotation of the conveyor belt 51, inverts it, and feeds it again between the counter roller 46 and the conveyor belt 51. The upper surface of this duplex unit 71 serves as a manual feed tray 72.

[0025] As shown in FIG. 3, a maintenance and recovery mechanism 81 including recovery means for maintaining and recovering the state of the nozzles of the recording head 34 is disposed in a non-printing area on one side of the carriage 33 in the scanning direction.

[0026] This maintenance and recovery mechanism 81 includes cap members (hereinafter referred to as "caps") 82a to 82d (referred to as "caps 82" when no distinction is made) for capping the nozzle faces of the recording head 34, a wiper blade 83 which is a blade member for wiping the nozzle faces, and an idle discharge receiver 84 for receiving droplets when idle discharge is performed to discharge droplets that do not contribute to recording in order to expel thickened recording liquid. Here, cap 82a is used as a suction and moisture retention cap, and the other caps 82b to 82d are moisture retention caps.

[0027] Waste recording liquid generated by the maintenance and recovery operation by the maintenance and recovery mechanism 81 is discharged and stored in the waste liquid tank 23 (see FIG. 6). Ink discharged into the cap 82, ink adhering to the wiper blade 83 and removed by the wiper cleaner, and ink idling discharged into the idling discharge receiver 84 are also discharged and stored in the waste liquid tank 23 (see FIG. 6).

[0028] 3, a blank discharge receiver 88 is disposed in the non-printing region on the other side in the scanning direction of the carriage 33. The blank discharge receiver 88 receives droplets when blank discharge is performed to discharge droplets that do not contribute to recording in order to discharge recording liquid that has thickened during recording, etc. This blank discharge receiver 88 is provided with an opening 89 aligned in the nozzle row direction of the recording head 34.

[0029] In the inkjet recording device 100 of the present invention thus configured, the sheets 42 are separated and fed one by one from the paper feed tray 2, and the sheets 42 fed substantially vertically upward are guided by the guide member 45. Then, the sheets 42 are sandwiched between the conveyor belt 51 and the counter roller 46 and conveyed, and the leading edge of the sheets is guided by the conveyor guide member 47 and pressed against the conveyor belt 51 by the leading edge pressure roller 49, and the conveying direction is changed by approximately 90°.

[0030] At this time, an AC bias supply unit of the control unit, which will be described later, applies an alternating voltage to the charging roller 56 so that positive and negative outputs are alternately repeated. As a result, the conveyor belt 51 is charged with an alternating charging voltage pattern, i.e., positive and negative charges are alternately charged in a band shape of a predetermined width in the sub-scanning direction, which is the rotation direction. When the paper 42 is fed onto the conveyor belt 51 which is alternately positively and negatively charged, the paper 42 is attracted to the conveyor belt 51, and the paper 42 is conveyed in the sub-scanning direction by the rotation of the conveyor belt 51.

[0031] Next, while moving the carriage 33 in the main scanning direction, the recording head 34 is driven in response to an image signal. The recording head 34 ejects ink droplets onto the stationary paper 42 to record one line, and after transporting the paper 42 a predetermined distance, records the next line. Upon receiving a recording end signal or a signal indicating that the rear end of the paper 42 has reached the recording area, the recording operation ends and the paper 42 is discharged to the paper discharge tray 3.

[0032] Furthermore, during standby for printing (recording), the carriage 33 is moved to the maintenance and recovery mechanism 81 side, and the recording head 34 is capped with a cap 82, and by keeping the nozzles wet, ejection failures due to dried ink are prevented. With the recording head 34 capped with the cap 82, the suction pump 22 (see FIG. 6) sucks the recording liquid from the nozzles (called "nozzle suction" or "head suction"), performing a recovery operation to expel thickened recording liquid and air bubbles. Furthermore, before the start of recording or during recording, a blank ejection operation is performed to eject ink unrelated to recording. These operations enable the recording head 34 to maintain stable ejection performance.

[0033] 4 is an overall block diagram showing an example of a control unit of a liquid ejection device. This control unit includes a main control unit 301 that controls the entire inkjet recording device, and a print control unit 302 that controls printing. The main control unit 301 and the print control unit 302 are configured with a microcomputer.

[0034] The main control unit 301 forms an image on the paper 42 based on the printing process information input from the communication circuit 300. Specifically, it drives and controls the main scanning motor via a main scanning motor drive circuit 303 to move the carriage 33 in the main scanning direction, and drives and controls the sub-scanning motor via a sub-scanning motor drive circuit 304 to transport the paper 42. It also sends printing data to the print control unit 302.

[0035] Furthermore, a detection signal from a carriage position detection circuit 305 that detects the position of the carriage 33 is input to the main control unit 301, and the main control unit 301 controls the movement position and movement speed of the carriage 33 based on this detection signal. The carriage position detection circuit 305 detects the position of the carriage 33, for example, by reading and counting the number of slits in an encoder sheet arranged in the scanning direction of the carriage 33 with a photosensor mounted on the carriage 33. The main scanning motor drive circuit 303 rotates and drives the main scanning motor in accordance with the carriage movement amount input from the main control unit 301, and moves the carriage 33 to a predetermined position at a predetermined speed.

[0036] Furthermore, a detection signal from a transport amount detection circuit 306 that detects the amount of movement of the conveyor belt 51 is input to the main control unit 301, and the main control unit 301 controls the amount of movement and the speed of movement of the conveyor belt 51 based on this detection signal. The transport amount detection circuit 306 detects the amount of transport, for example, by reading and counting the number of slits in a rotary encoder sheet attached to the rotation shaft of the conveyor roller 52 with a photosensor. The sub-scanning motor drive circuit 304 rotates and drives the sub-scanning motor in accordance with the amount of transport input from the main control unit 301, and rotates and drives the conveyor roller 52 to move the conveyor belt 51 to a predetermined position at a predetermined speed.

[0037] The main control unit 301 rotates the paper feed roller 43 once by giving a paper feed roller drive command to the paper feed roller drive circuit 307. The main control unit 301 drives the motor of the maintenance and recovery mechanism 81 via the maintenance and recovery mechanism drive motor drive circuit 308 to raise and lower the cap 82, raise and lower the wiper blade 83, drive the suction pump 22, and the like, as described above.

[0038] The main control unit 301 controls the drive motor (supply motor) for driving the pump of the liquid feed pump 24 via the supply pump drive circuit 311, and replenishes (fills) the head tank 35 with ink from the ink cartridge 10 loaded in the cartridge loading unit 4. At this time, the main control unit 301 controls the replenishment (filling operation) based on a detection signal from a head tank full sensor 312 that detects that the head tank 35 is full. In this case, there is atmospheric open filling, in which filling is performed with the atmospheric open portion (atmospheric open valve 94) of the head tank 35 in an open state, and normal filling, in which filling is performed with the atmospheric open portion closed.

[0039] Furthermore, the main control unit 301 retrieves information stored in a non-volatile memory 316, which is an information storage element provided in each ink cartridge 10 mounted in the cartridge loading unit 4, through the cartridge communication circuit 314. Then, the main control unit 301 performs required processing and stores and holds the information in a non-volatile memory (e.g., EEPROM) 315, which is an information storage element of the main body.

[0040] Furthermore, main control unit 301 receives detection signals from an environment sensor 313 that detects the environmental temperature and humidity.

[0041] The print control unit 302 generates data for driving a pressure generating means for ejecting droplets from the recording head 34, based on a signal from the main control unit 301 and the carriage position and transport amount from a carriage position detection circuit 305 and a transport amount detection circuit 306. The print control unit 302 also transfers the above-mentioned image data as serial data to a head drive circuit 310, and outputs to the head drive circuit 310 a transfer clock, a latch signal, a droplet control signal (mask signal), and the like, which are required for transferring this image data and confirming the transfer.

[0042] The print control unit 302 also includes a drive waveform generation unit composed of a D / A converter that performs D / A conversion on the drive signal pattern data stored in the ROM, a voltage amplifier, a current amplifier, etc., and a drive waveform selection means that supplies the drive waveform to the head driver. The print control unit 302 generates a drive pulse (drive signal) or a drive waveform composed of multiple drive pulses (drive signals) and outputs it to the head drive circuit 310.

[0043] The head drive circuit 310 selectively applies drive signals constituting a drive waveform provided by the print control unit 302 based on serially input image data corresponding to one line of the recording head 34 to the drive elements of the recording head 34, thereby driving the recording head 34. Here, the drive elements are, for example, piezoelectric elements as described above, and generate energy for ejecting droplets from the recording head 34.

[0044] At this time, by selecting the drive pulses that make up the drive waveform, it is possible to print dots of different sizes, such as large droplets (large dots), medium droplets (medium dots), and small droplets (small dots).

[0045] 5 is a perspective view showing the structure of a head tank according to one embodiment of the present invention. In the figure, a film 92 provided inside the head tank 35 is biased by a spring to generate negative pressure, and is displaced according to the consumption amount of ink stored in the head tank. A negative pressure lever 91 is a lever that moves in accordance with the film 92.

[0046] The supply port 93 is a supply port through which ink is supplied from the ink cartridge 10 via the ink supply tube 36 (see Figs. 1 and 3). The air release valve 94 is a pin that opens the inside of the head tank 35 to the atmosphere as necessary. Furthermore, the recording head 34 that ejects ink droplets is attached below the head tank 35. Furthermore, a detection mechanism 95 that detects ink or air is provided.

[0047] Fig. 6 is a schematic diagram showing the discharge of ink from the head tank. As shown in Fig. 6, when the nozzle surface of the recording head 34 is covered with the cap 82 and suction is performed by the suction pump 22, the ink in the head tank 35 can be discharged (head suction) to the waste liquid tank 23. This head suction can remove thickened ink from the nozzles.

[0048] Here, by applying head suction while blocking off the atmosphere, the pressure inside the head tank 35 can be lowered and negative pressure can be created (negative pressure lever 91 is closed). On the other hand, by applying head suction while opening to the atmosphere, the liquid level inside the head tank 35 can be lowered (negative pressure lever 91 is left open).

[0049] Fig. 7 is a schematic diagram showing the configuration of ink supply piping according to one embodiment of the present invention. As shown in Fig. 7, the inkjet recording apparatus 100 of this embodiment includes a liquid feed pump 24 that can forwardly and reversely transfer liquid between the head tank 35 and the ink cartridge 10. That is, the liquid feed pump 24 feeds liquid from the ink cartridge 10 to the head tank 35 during "forward rotation", and returns liquid from the head tank 35 to the ink cartridge 10 during "reverse rotation" (circulation of liquid).

[0050] The inkjet recording apparatus 100 of this embodiment forward transfers liquid with the liquid feed pump 24 while opening to the atmosphere with the air release valve 94, and detects the liquid level in the head tank 35 with an electrode pin (detection mechanism 95). By stopping the liquid feed pump 24 at the point in time when the liquid level is detected, the head tank 35 can be filled up with liquid.

[0051] The liquid feed pump 24 used in the present invention does not have a complex pump structure and employs a tube pump 30 as shown in Fig. 8, which can feed ink in both directions by changing the rotation direction of the drive motor. A rubber tube 25 for feeding liquid runs through the inside of the tube pump 30. The rubber tube 25 is locally crushed by a pump rotor 27 built into the pump, and the pump rotor 27 is rotated to move the crushed point in the rotation direction, thereby feeding ink in the rotation direction of the pump rotor 27.

[0052] Specifically, when transferring ink forward from the ink cartridge 10 to the head tank 35, the pump rotor 27 is rotated in the direction of arrow A. On the other hand, when transferring ink backward from the head tank 35 to the ink cartridge 10, the pump rotor 27 is rotated in the direction of arrow B. Here, the rotation of the pump rotor 27 in the direction of arrow A is referred to as forward rotation, and the rotation in the direction of arrow B is referred to as reverse rotation. Therefore, by controlling the rotation of the pump rotor 27 forward and reverse, the ink transfer direction can be controlled.

[0053] In addition, by using the tube pump 30 with a simple structure for the liquid delivery pump 24, the pump structure can be made to occupy a small space. Furthermore, since the liquid delivery direction can be controlled by controlling the forward and reverse rotation of the pump drive motor, the piping can be simplified. Note that the structure of the tube pump 30 is not limited to the rotating roller type as shown in Figure 8, and it may be of a vari-center cam type or the like.

[0054] Fig. 9 is a schematic diagram explaining the change in the liquid level in the head tank and the film behavior. Fig. 9(a) shows the full tank state, Fig. 9(b) shows the state where negative pressure is generated, and Fig. 9(c) shows the state where the tank is open to the atmosphere and the liquid level is lowered.

[0055] As shown in Fig. 9(a), when the head tank 35 is full and the air release valve 94 (see Fig. 5) is closed, suction by the suction pump 22 (see Fig. 6) causes the film 92 (see Fig. 5) to close, generating negative pressure in the head tank, resulting in a transition to the state shown in Fig. 9(b). At this time, the height of the liquid surface hardly changes. This is the same for the reverse transfer liquid by the liquid feed pump 24 (see Fig. 7) or the ink ejection by the recording head 34.

[0056] In addition, in the head tank 35 shown in Fig. 9(b), when the air release valve 94 is opened, the film 92 opens and the liquid level drops, transitioning to the state shown in Fig. 9(c). Note that the greater the negative pressure, the greater the degree to which the liquid level drops and the degree to which the film 92 opens.

[0057] 9(c), when the air release valve 94 is closed and the liquid transfer pump 24 transfers the liquid forward, the liquid level rises and transitions to the state shown in FIG. 9(a). When the detection mechanism 95 (see FIG. 5) detects the liquid level, the liquid transfer pump 24 stops transferring the liquid forward.

[0058] In the head tank 35 shown in Figures 9(a) and (b), when the atmosphere release valve 94 is closed and the liquid is transferred forward by the liquid transfer pump 24, the liquid level hardly changes, but the degree to which the film 92 opens increases.

[0059] The ink end detection for the ink cartridge 10 is performed as follows. With reference to Figures 5 and 7, when the ink cartridge 10 is empty, if ink is consumed by ink ejection, head suction, etc., the pressure inside the film 92 decreases. When the pressure inside the film 92 decreases, the negative pressure lever 91, which is the pressure detection means, is displaced, and when it crosses the negative pressure lever sensor, it is determined that the ink cartridge 10 is empty (ink end detection).

[0060] Furthermore, in this embodiment, remaining liquid amount data is stored (memorized) in the information storage element provided in the ink cartridge 10 of each color, and the remaining ink amount can be found by subtracting the amount consumed from that data. The cumulative ink consumption amount in the ink cartridge 10 of each color is the sum of the ink amount due to head suction and ejection. In other words, it can be calculated as (remaining ink amount) = (ink volume) - (ink consumption amount).

[0061] The negative pressure lever 91, the negative pressure lever sensor, and the information storage element provided in the ink cartridge 10 are an example of a liquid detection unit that detects the remaining amount of liquid in the ink cartridge 10.

[0062] Fig. 10 is a schematic diagram showing the configuration of the automatic maintenance mechanism in the device shown in Fig. 1. As shown in Fig. 10, the automatic maintenance mechanism includes an ink cartridge 10, a liquid feed pump 24, a head tank 35, a recording head 34, a cap 82, a suction pump 22, a waste liquid tank 23, a wiper blade 83, and an empty discharge receiver 84. Here, the ink cartridge 10 contains inks of the following colors from the left in the figure: white (W1, W2), black (K), cyan (C), magenta (M), and yellow (Y).

[0063] Next, a characteristic configuration of the present invention will be described.

[0064] (First embodiment) Fig. 11 is a schematic diagram showing a white ink cartridge left without shaking, and Fig. 12 is a schematic diagram explaining the ink density when the white ink cartridge is in use. In an ink cartridge filled with heavy pigment ink such as white ink, the high-density ink collects at the bottom of the container, and the ink density at the top of the container is low. In addition, even when the ink cartridge is mounted in an inkjet recording device and ink is discharged, the ink density increases as the actual remaining amount of ink decreases.

[0065] It has been confirmed through experiments that this thick ink is prone to solidifying in the nozzles of the recording head 34, as shown in FIG. 13, which can easily cause nozzle non-ejection and reduce the recovery ability of the nozzles.

[0066] In response to these problems, in this embodiment, the user is prompted to replace the ink cartridge before the ink in the ink cartridge becomes too thick, and automatic maintenance is performed.

[0067] First, Table 1 shows the terms and their definitions that indicate the state of the ink cartridge (amount of ink remaining), and whether printing is possible (whether printing is possible or not).

[0068] [Table 1]

[0069] As shown in Table 1, when the ink cartridge state is from "normal" to "near end", printing is possible (printing is possible), but when it is in the "first end" or "second end" state, printing is not possible (printing is not possible). Note that the values ​​in Table 1 are just examples. They may be set arbitrarily according to the specifications of the actual device.

[0070] The ink cartridge being in the "second end" state means that (a) even if the ink in the ink cartridge 10 is forward-transferred by the liquid feed pump 24, the liquid level in the head tank 35 cannot be detected by the electrode pin (detection mechanism 95). Also, "zero" here means that the amount of ink in the ink cartridge is below the detectable limit from zero.

[0071] In addition, the inkjet recording apparatus 100 of this embodiment sets "whether automatic maintenance is possible" according to the state of the ink cartridge. Table 2 shows "whether printing is possible", "whether automatic maintenance is possible", and "user action" according to the state of the ink cartridge.

[0072] [Table 2]

[0073] Here, automatic maintenance consists of (1) "ink circulation operation" performed every hour, (2) "cleaning operation" performed every three hours, and (3) "ink agitation alert" performed every 12 hours. The contents of each operation are explained below in order.

[0074] (Ink circulation operation) The ink circulation operation will be described with reference to FIG. 7 shown above. The main control unit 301 of the inkjet recording apparatus 100 rotates the liquid feed pump 24 in the forward and reverse directions to circulate the ink in the supply path (head tank 35 - ink supply tube 36 - ink cartridge 10) without discharging the ink. This series of operations is called the ink circulation operation. Note that in this embodiment, it is performed every hour, but this may be determined arbitrarily according to the device specifications.

[0075] This ink circulation operation eliminates imbalances in the components of inks that have a high tendency to settle (especially white ink), making it easier to resolve issues such as "different image colors," "nozzle failure," and / or "deterioration of nozzle recovery."

[0076] The ink circulation operation may be performed by including the recording head 34 in the supply path.

[0077] (cleaning operation) 14 is a flow chart showing the cleaning operation for improving the nozzle condition. The cleaning operation will be explained using this flow chart.

[0078] First, in step S01, the main control unit 301 of the inkjet recording apparatus 100 drives the liquid feed pump 24 to supply ink from the ink cartridge 10 to the head tank 35. Next, the process proceeds to step S02, where the main control unit 301 performs head suction by driving the suction pump 22. This causes ink to be discharged and ink to be supplied to the head tank 35.

[0079] Next, the process proceeds to step S03, where the wiping operation is performed. That is, the main control unit 301 drives the suction pump 22 to lower the cap 82, drives the main scanning motor to move the carriage 33 to the wiping start position, drives the suction pump 22 to raise the wiper blade 83, and drives the main scanning motor to move the carriage 33 to the wiping end position.

[0080] Next, the process proceeds to step S04, where the main control unit 301 drives the main scanning motor to move the carriage 33 to the capping position, and causes each recording head 34 to eject ink (idle ejection and preliminary ejection). This makes it possible to remove mixed ink in the vicinity of the nozzles. Next, the process proceeds to step S05, where the main control unit 301 drives the suction pump 22 to suck the ink inside the cap. By removing the ink inside the cap, it is possible to prevent ink from mixing during capping. Then, the process proceeds to step S06, where the main control unit 301 drives the suction pump 22 to perform capping, and the cleaning operation is completed.

[0081] In the above flow chart, head suction (step S02) is performed, but instead, ink may be discharged by applying pressure to each recording head 34.

[0082] (ink stir alert) The ink stirring alert is, for example, to display a screen such as that shown in Fig. 15 on the notification unit 5 of the device main body 1 to prompt the user to shake (stir) the white ink cartridge. Also, when the corresponding white ink cartridge is removed and then re-installed, the above screen disappears.

[0083] Stirring the affected cartridge will eliminate any imbalances in the components of inks that are prone to settling (especially white ink), making it easier to resolve issues such as "different image colors," "nozzle failure," and / or "deterioration in nozzle recovery."

[0084] The inkjet recording apparatus 100 of this embodiment configured as above operates as follows.

[0085] (1) When the remaining amount of ink in the ink cartridge is "normal" (liquid remaining amount is equal to or greater than a predetermined amount), the inkjet recording apparatus 100 is placed in a printable state. (2) When the ink remaining in the ink cartridge is at the "first end" (less than a predetermined amount of liquid remaining), the inkjet recording device 100 is placed in a state in which printing is not possible (printing is not possible). The notification unit 5 issues a notification that the ink cartridge is empty or a notification to prompt replacement of the ink cartridge. Furthermore, the inkjet recording device 100 (its automatic maintenance mechanism) is placed in a state in which "automatic maintenance" can be performed. (3) When the ink remaining in the ink cartridge is at the "second end" (no liquid remaining), the inkjet recording apparatus 100 is placed in a state in which "automatic maintenance" cannot be performed.

[0086] When the inkjet recording apparatus 100 is in a state in which printing is not possible, it is preferable to continue the "automatic maintenance (cleaning operation)" as long as the remaining amount of ink can be detected.

[0087] The above details are shown in Table 3.

[0088] [Table 3]

[0089] In this way, when the ink remaining in the ink cartridge reaches the "first end", the inkjet recording device 100 of this embodiment enters a printing disabled state and prompts the user to replace the ink cartridge. This makes it possible to suppress quality changes such as an increase in the density of the printed matter. In addition, automatic maintenance can be performed, so adverse effects on the liquid ejection performance and nozzles can be suppressed.

[0090] (Variation 1) In the case of inks with relatively little pigment sedimentation, such as black (K), cyan (C), magenta (M), and yellow (Y), the ink concentration does not change much over time, so the ink cartridge can be used up until it is empty. Therefore, the inkjet recording device 100 of the modified example performs the following operation.

[0091] (A) For ink cartridges containing specific inks (inks with heavy pigments such as white ink), (1) When the remaining amount of ink in the ink cartridge is "normal" (liquid remaining amount is equal to or greater than a predetermined amount), the inkjet recording apparatus 100 is placed in a printable state. (2) When the ink remaining in the ink cartridge is at the "first end" (less than a predetermined amount of liquid remaining), the inkjet recording device 100 is placed in a state in which printing is not possible. The notification unit 5 issues a notification that the ink cartridge is empty or a notification urging the user to replace the ink cartridge. Furthermore, the inkjet recording device 100 (its automatic maintenance mechanism) is placed in a state in which "automatic maintenance" can be performed. (3) When the ink remaining in the ink cartridge is at the "second end" (no liquid remaining), the inkjet recording apparatus 100 is placed in a state in which "automatic maintenance" cannot be performed.

[0092] (B) For ink cartridges that contain ink other than the specified ink (black, cyan, magenta, yellow, etc.), (1) When the remaining amount of ink in the ink cartridge is "normal" (liquid remaining amount is equal to or greater than a predetermined amount), the inkjet recording apparatus 100 is placed in a printable state. (2) When the ink remaining in the ink cartridge is at the "second end" (no liquid remaining), the inkjet recording device 100 is placed in a state in which printing is not possible. The notification unit 5 notifies the user that the ink cartridge is empty or prompts the user to replace the ink cartridge. However, "automatic maintenance" will not be possible.

[0093] When the inkjet recording apparatus 100 is in a state in which printing is not possible, it is preferable to continue the "automatic maintenance (cleaning operation)" as long as the remaining amount of ink can be detected.

[0094] The above details are shown in Table 4.

[0095] [Table 4]

[0096] By doing this, it is possible to use up inks with relatively little pigment sedimentation, such as black (K), cyan (C), magenta (M), and yellow (Y), while suppressing any adverse effects on the liquid ejection performance and nozzles of the recording head that ejects a specific ink (for example, white ink).

[0097] Subsequently, advantageous configurations of the invention will be explained.

[0098] (Configuration 1) When the ink level in the ink cartridge reaches the "second end" (no liquid level remaining), the notification unit 5 issues a notification that the ink cartridge 10 is empty or a notification that prompts the user to replace the ink cartridge 10. Also, when the ink level in the ink cartridge reaches the "first end" (less than a predetermined amount of liquid remaining), the notification unit 5 issues a notification that the ink cartridge 10 is empty or a notification that prompts the user to replace the ink cartridge 10.

[0099] Here, it is desirable that the notification when the ink level in the ink cartridge reaches the "second end" (no liquid remaining) and the notification when the ink level in the ink cartridge reaches the "first end" (less than a predetermined amount of liquid remaining) are the same. At the "first end" point (less than a predetermined amount of liquid remaining), the user can be notified that the ink is out and be prompted to replace the ink cartridge, thereby reducing the risk of adverse effects on the liquid ejection performance and nozzles.

[0100] (Configuration 2) If the power is turned off when there is very little ink remaining in the ink cartridge, the inkjet recording apparatus 100 will be unable to carry out "automatic maintenance."

[0101] Therefore, when the ink level in the ink cartridge is at the "first end" (liquid level remaining is less than a predetermined amount) and the inkjet recording device 100 is in a state in which "automatic maintenance" can be performed, if a user inputs an instruction to turn off the power to the device main body 1, it is desirable for the notification unit 5 to notify the user of a warning.

[0102] 16 shows an example of a warning that is displayed on the display of the notification unit 5. This can reduce the risk that the device main body 1 will be left in the power-off state.

[0103] (Configuration 3) It is desirable that the amount of ink (amount of liquid) actually contained in the ink cartridge 10 be greater than the amount of liquid marked on the ink cartridge 10 (a value that can be visually recognized by the user).

[0104] For example, for a white ink cartridge with an actual ink filling volume of 250 ml, the indication (label, etc.) is 200 ml, and the remaining liquid volume data written to the information storage element unit of the ink cartridge 10 is 200 ml. In this way, when the liquid detection unit detects the first end (remaining ink volume is 1% or less of the total volume), the actual ink filling volume will be approximately 50 ml, and an increase in ink concentration can be suppressed. This further suppresses adverse effects on the liquid ejection performance and nozzles. Also, since the indicated ink volume can be used reliably, no disadvantage is caused to the user.

[0105] Second embodiment Specific inks (e.g., white ink, metallic ink, etc.) are generally used less frequently than normal inks (black (K), cyan (C), magenta (M), yellow (Y), etc.). Therefore, when the remaining amount of a specific ink falls below a predetermined amount, it is desirable to make the specific ink unprintable (unprintable) and make the normal ink printable. This can improve the convenience of the inkjet recording device 100.

[0106] The above details are shown in Table 5.

[0107] [Table 5]

[0108] Third embodiment As explained above, the cleaning operation, which is one type of automatic maintenance, is performed by supplying ink in the ink cartridge 10 to the recording head 34 (see FIG. 14). In this embodiment, as a second cleaning operation, the nozzle surface of the recording head 34 is cleaned without using ink (that is, it is possible to switch between the first cleaning and the second cleaning).

[0109] 17 is a flowchart showing a second cleaning operation for improving the nozzle condition without supplying ink. The cleaning operation without using ink will be described using this flowchart.

[0110] First, in step S01-1, the main control unit 301 of the inkjet recording apparatus 100 opens the atmosphere release valve 94 to open the head tank 35 to the atmosphere. Next, the process proceeds to step S01-2, where the main control unit 301 opens the atmosphere release valve 94. As a result, the internal pressure of the head tank 35 becomes equal to atmospheric pressure. Next, the process proceeds to step S02, where the main control unit 301 drives the suction pump 22 to suck the head. As a result, the remaining ink in the head tank 35 can be discharged.

[0111] Next, the process proceeds to step S03, where the wiping operation is performed. That is, the main control unit 301 drives the suction pump 22 to lower the cap 82, drives the main scanning motor to move the carriage 33 to the wiping start position, drives the suction pump 22 to raise the wiper blade 83, and drives the main scanning motor to move the carriage 33 to the wiping end position.

[0112] Next, the process proceeds to step S04, where the main control unit 301 drives the main scanning motor to move the carriage 33 to the capping position, and causes each recording head 34 to eject ink (idle ejection and preliminary ejection). This makes it possible to remove mixed ink in the vicinity of the nozzles. Next, the process proceeds to step S05, where the main control unit 301 drives the suction pump 22 to suck the ink inside the cap. By removing the ink inside the cap, it is possible to prevent ink from mixing during capping. Then, the process proceeds to step S06, where the main control unit 301 drives the suction pump 22 to perform capping, and the cleaning operation is completed.

[0113] In the above flow chart, head suction (step S02) is performed, but instead, ink may be discharged by applying pressure to each recording head 34.

[0114] In the inkjet recording apparatus 100 of this embodiment configured as above, in addition to the operation of the above-described embodiment, (3) When the ink remaining in the ink cartridge is at the “second end” (no liquid remaining), the second cleaning operation can be performed after the head tank is opened to the atmosphere.

[0115] By doing so, cleaning is carried out even when there is no ink left in the ink cartridge, so that adverse effects on the liquid ejection performance and the nozzles can be further suppressed.

[0116] (Fourth embodiment) As explained above, the ink circulation operation, which is one of the automatic maintenance operations, is an operation in which the ink is circulated between the supply path (head tank 35 to ink cartridge 10) by the liquid feed pump 24 (FIG. 7). In this embodiment, the liquid feed pump 24 is kept in an operable state even when the ink is used up, and thick ink is prevented from remaining in the supply path.

[0117] That is, in the inkjet recording apparatus 100 of this embodiment, in addition to the operations of the above-described embodiment, (3) When the ink remaining in the ink cartridge reaches the “second end” (no liquid remaining), the liquid feed pump 24 is enabled to operate.

[0118] By doing so, dark ink is less likely to accumulate in the supply path (from the head tank 35 to the ink cartridge 10), and problems caused by ink solidification can be suppressed.

[0119] Fifth embodiment In the first embodiment, it has been described that the cleaning operation can be performed until the ink cartridge 10 is empty. In the present embodiment, in addition to that configuration, even if the ink cartridge 10 is empty, if there is ink in the head tank 35, the cleaning operation is performed using that ink.

[0120] That is, in the inkjet recording apparatus 100 of this embodiment, in addition to the operation of the first embodiment described above, (3) The cleaning operation can be performed until the ink remaining in the head tank 35 becomes zero.

[0121] Doing so is advantageous in that adverse effects on the liquid ejection performance and nozzles can be suppressed for a longer period of time.

[0122] Sixth embodiment In the present invention, even if the ink cartridge is in a state where printing is not possible (printing is not possible), there is still enough ink remaining in the ink cartridge to allow maintenance (see Tables 1 and 2). Therefore, in this embodiment, the inkjet recording device is temporarily changed to a state where printing is possible at the user's instruction, making it possible to print.

[0123] Specifically, the inkjet recording apparatus 100 of this embodiment operates as follows.

[0124] (1) When the remaining amount of ink in the ink cartridge is "normal" (liquid remaining amount is equal to or greater than a predetermined amount), the inkjet recording apparatus 100 is placed in a printable state. (2) When the ink remaining in the ink cartridge is at the "first end" (less than a predetermined amount of liquid remaining), the inkjet recording device 100 is placed in a state in which printing is not possible (printing is not possible). The notification unit 5 issues a notification that the ink cartridge is empty or a notification to prompt replacement of the ink cartridge. Furthermore, the inkjet recording device 100 (its automatic maintenance mechanism) is placed in a state in which "automatic maintenance" can be performed. (2a) Here, when a print instruction is received from the user, the inkjet recording apparatus 100 changes to a printable state and performs printing. Note that the print instruction from the user is given, for example, by pressing the paper feed / print resume button 13 (see FIG. 1). (2b) When printing is completed, the inkjet recording device 100 is again placed in a state where printing is not possible. The notification unit 5 issues a notification that the ink cartridge is empty or a notification to prompt replacement of the ink cartridge. Furthermore, the inkjet recording device 100 (its automatic maintenance mechanism) is placed in a state where "automatic maintenance" can be performed. (3) When the ink remaining in the ink cartridge is at the "second end" (no liquid remaining), the inkjet recording apparatus 100 is placed in a state in which "automatic maintenance" cannot be performed.

[0125] When the inkjet recording apparatus 100 is in a state in which printing is not possible, it is preferable to continue the "automatic maintenance (cleaning operation)" as long as the remaining amount of ink can be detected.

[0126] The above details are shown in Table 6.

[0127] [Table 6]

[0128] In this way, the inkjet recording device 100 of this embodiment becomes unable to print when the ink remaining in the ink cartridge reaches the "first end", but changes to a printable state when a print instruction is received. Therefore, even if printing becomes unable to print when there is little time left until completion, printing can be temporarily resumed and completed, improving user convenience.

[0129] In particular, if the user has a replacement ink cartridge prepared in advance, the ink cartridge currently being used may be replaced after the ink has been used up, which is more economical.

[0130] (Modification) In the case of inks with relatively little pigment sedimentation, such as black (K), cyan (C), magenta (M), and yellow (Y), the ink concentration does not change much over time, so the ink cartridge is used up until it is empty. Then, for ink cartridges that contain a specific ink (e.g., white ink), the ink cartridge may be set to a non-printable state when the ink level reaches the "first end," and may be changed to a printable state when a print instruction is received from the user.

[0131] The above details are shown in Table 7.

[0132] [Table 7]

[0133] By doing this, when the ink level reaches the "first end" for a specific ink (e.g., white ink), the user is prompted to replace the cartridge, and at the user's command, the inkjet recording device is temporarily put into a printable state, allowing printing to be completed.

[0134] Seventh embodiment Continuing printing when the ink remaining amount is less than the "first end" is merely a temporary measure, and cartridge replacement is required to prevent malfunctions. Therefore, when the inkjet recording apparatus 100 of this embodiment receives a print command and changes to a printable state, it notifies the user of this and calls their attention.

[0135] 18 and 19 are schematic diagrams showing an example of a screen display at the first end, which is displayed on the display of the notification unit. At the "first end", the inkjet recording device 100 displays the screen shown in Fig. 18 on the notification unit 5 of the device main body 1, and notifies the user to confirm whether or not to change to a printable state.

[0136] When the "Printable / Unprintable" button shown in the center of Fig. 18 is pressed (touched), the screen shown in Fig. 19(a) is displayed on the notification unit 5. This is intended to inform the user that the ink cartridge is low on ink and that image defects or ejection defects are likely to occur unless the ink cartridge is replaced.

[0137] Here, if the user presses (touches) "YES", the inkjet recording apparatus 100 changes from a print-disabled state to a print-enabled state. On the other hand, if the user presses (touches) "NO", the inkjet recording apparatus 100 remains in the print-disabled state.

[0138] As an alternative example, as shown in Fig. 19(b), a screen for repeatedly calling the user's attention may be displayed on the notification unit 5. When the user presses (touches) "YES" shown in the upper diagram of Fig. 19(b), the screen shown in the lower diagram is then displayed on the notification unit 5. This is intended to inform the user that image defects or ejection defects are more likely to occur if printing is resumed (urgent printing).

[0139] If the user further presses (touches) "YES" here, the inkjet recording apparatus 100 changes from the unprintable state to the printable state. On the other hand, if the user presses (touches) "NO", the inkjet recording apparatus 100 remains in the unprintable state.

[0140] In this way, this embodiment notifies the user that there is a risk of printing after the remaining ink level reaches the "first end," and changes the state to one that is ready for printing after obtaining the user's confirmation. This strongly urges the user to replace the ink cartridge, and reduces the risk of image defects or ejection defects.

[0141] Next, clear definitions are provided for terms used in this application.

[0142] The "printable state" and "unprintable state" refer to the liquid ejection device being able to accept or not able to accept a new print job, respectively, and / or displaying on the device (e.g., the notification unit 5) that printing is possible or not possible. This can be achieved, for example, by the control unit (FIG. 4) having internal information (parameters) for control.

[0143] Furthermore, the "printable state" and "unprintable state" can be determined by whether the device starts printing when a print job is instructed (by a user, etc.).

[0144] A "liquid ejection device" is a device that includes a liquid ejection head or a liquid ejection unit, and ejects liquid by driving the liquid ejection head. Devices that eject liquid include not only devices that can eject liquid onto objects to which the liquid can adhere, but also devices that eject liquid into air or liquid.

[0145] This "liquid ejection device" can also include means for feeding, transporting, and discharging objects onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0146] Examples of "liquid ejection devices" include image forming devices that eject ink to form an image on paper, and three-dimensional modeling devices that eject modeling liquid onto a powder layer formed by layering powder in order to create a three-dimensional object.

[0147] Furthermore, the term "liquid ejection device" is not limited to devices that visualize meaningful images such as characters and figures by ejecting liquid. For example, it also includes devices that form patterns that have no meaning in themselves and devices that create three-dimensional images.

[0148] The above-mentioned "object to which liquid can adhere" means an object to which liquid can adhere at least temporarily, and to which the liquid adheres and sticks, or to which the liquid adheres and penetrates, etc. Specific examples include media such as paper, recording paper, film, cloth, and other recording media, electronic boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all objects to which liquid can adhere.

[0149] The material of the above-mentioned "object to which liquid can adhere" may be any material to which liquid can adhere even temporarily, such as paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics, building materials such as wallpaper and flooring, and textiles for clothing.

[0150] The "liquid" may be any liquid having a viscosity and surface tension that allows it to be discharged from the head, and is not particularly limited, but it is preferable that the viscosity is 30 mPa·s or less at room temperature and pressure, or by heating or cooling. More specifically, it is a solution, suspension, emulsion, etc. containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a functionalizing material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, an amino acid, a protein, or calcium, an edible material such as a natural dye, etc. These can be used for applications such as inkjet ink, a surface treatment liquid, a liquid for forming a component of an electronic element or a light-emitting element, an electronic circuit resist pattern, a material liquid for three-dimensional modeling, etc.

[0151] Furthermore, the term "liquid ejection device" includes devices in which a liquid ejection head and an object to which liquid can be attached move relatively, but is not limited to this. Specific examples include serial type devices in which a liquid ejection head moves, and line type devices in which a liquid ejection head does not move.

[0152] Other examples of "liquid ejection devices" include treatment liquid application devices that eject treatment liquid onto paper to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There are also jet granulation devices that eject a composition liquid in which raw materials are dispersed through a nozzle to granulate fine particles of the raw materials.

[0153] A "liquid ejection unit" is a collection of components related to ejecting liquid, in which functional parts and mechanisms are integrated with a liquid ejection head. For example, a "liquid ejection unit" includes a combination of a liquid ejection head and at least one of the following components: a head tank, a carriage, a supply mechanism, a maintenance and recovery mechanism, and a main scanning movement mechanism.

[0154] Here, integration includes, for example, a liquid ejection head, a functional part, and a mechanism that are fixed to each other by fastening, bonding, engaging, etc., and one is held movably relative to the other. The liquid ejection head, the functional part, and the mechanism may also be configured to be detachable from each other.

[0155] The main scanning movement mechanism includes the guide member alone, and the supply mechanism includes the tube alone and the loading unit alone.

[0156] A "liquid ejection head" is a functional device that ejects and sprays liquid from a nozzle. As an energy source for ejecting liquid, a piezoelectric actuator (a laminated piezoelectric element or a thin-film piezoelectric element), a thermal actuator that uses an electrothermal conversion element such as a heating resistor, an electrostatic actuator consisting of a vibration plate and an opposing electrode, etc. are used.

[0157] In this specification, "paper" does not mean a material limited to paper, but includes overhead projectors, cloth, glass, substrates, etc., and means anything onto which ink droplets or other liquids can adhere, including things called recording media, recording media, recording paper, recording paper, etc. In addition, image formation, recording, printing, copying, and printing are all synonymous terms.

[0158] Unless otherwise specified, the term "ink" is used as a general term for all liquids capable of forming an image, including not only those called ink, but also those called recording liquid, fixing treatment liquid, liquid, etc., and also includes, for example, DNA samples, resists, pattern materials, resins, etc.

[0159] The term "image" is not limited to flat objects, but also includes an image given to a three-dimensional object, and an image formed by three-dimensionally modeling a solid object itself.

[0160] The present invention has been described in detail above using the embodiments. The embodiments are merely examples, and various modifications can be made without departing from the scope of the present invention. For example, a plurality of the embodiments may be combined with each other. [Explanation of symbols]

[0161] 1. Device body 2 Paper feed tray 3 Output tray 4 Cartridge loading section 5. Notification Department 10 Ink Cartridges 12 Power button 13 Paper feed / resume printing button 14 Cancel button 21 Frame 21A, 21B side plate 22 Suction pump 23 Waste liquid tank 24 Liquid delivery pump 25 Rubber tube 27 Pump rotor 30 Tube Pump 31 Guide rod 32 Stay 33 Carriage 34 Recording head 35 Head Tank 36 Ink supply tube 41 Paper stacking section 42 Paper 43 Paper feed roller 44 Separation Pad 45 Guide member 46 Counter roller 47 Transport guide member 48 Retaining member 49 Tip pressure roller 51 Conveyor belt 52 Transport roller 53 Tension roller 56 Charging roller 57 Guide member 61 Separation claw 62 Paper ejection roller 63 Paper ejection roller 71 Double-sided unit 72 Manual feed tray 81 Maintenance and Recovery Mechanism 82 Cap 83 Wiper Blade 84, 88 Empty discharge receiver 89 Opening 91 Vacuum lever 92 Film 93 Supply Inlet 94 Atmospheric release valve 95 Detection Mechanism 100 Inkjet recording device 300 Communication Circuit 301 Main control unit 302 Printing control unit 303 Main scanning motor drive circuit 304 Sub-scanning motor drive circuit 305 Carriage position detection circuit 306 Transport amount detection circuit 307 Paper feed roller drive circuit 308 Motor drive circuit for driving the maintenance and recovery mechanism 310 Head drive circuit 311 Drive circuit for supply pump 312 Head tank full sensor 313 Environmental Sensor 314 Cartridge communication circuit 316 Non-volatile memory [Prior art documents] [Patent documents]

[0162] [Patent Document 1] JP 2010-155446 A

Claims

1. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a maintenance and recovery mechanism that performs a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head; An alarm unit that issues a sensory signal to a user; Equipped with (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; A liquid ejection device that, when a printing is not possible, issues a notification that the liquid cartridge is empty or a notification that urges a user to replace the liquid cartridge, and is capable of carrying out the cleaning operation, When the detected remaining amount of liquid becomes zero, a notification that the liquid cartridge is empty or a notification that prompts replacement of the liquid cartridge is issued; A liquid ejection device characterized in that, when the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, a notification that the liquid cartridge is empty or a notification urging the user to replace the liquid cartridge is issued in the same manner.

2. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a maintenance and recovery mechanism that performs a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head; An alarm unit that issues a sensory signal to a user; Equipped with (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; A liquid ejection device that, when a printing is not possible, issues a notification that the liquid cartridge is empty or a notification that urges a user to replace the liquid cartridge, and is capable of carrying out the cleaning operation, A liquid ejection device characterized in that when the detected remaining amount of liquid is less than a predetermined amount and the maintenance and recovery mechanism is in a state where the cleaning operation can be performed, when a user inputs an instruction to turn off the power to the device main body, the notification unit notifies the user of a warning.

3. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a maintenance and recovery mechanism that performs a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head; An alarm unit that issues a sensory signal to a user; Equipped with (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; A liquid ejection device that, when a printing is not possible, issues a notification that the liquid cartridge is empty or a notification that urges a user to replace the liquid cartridge, and is capable of carrying out the cleaning operation, A liquid ejection device, wherein the amount of liquid actually contained in the liquid cartridge is greater than the amount of liquid indicated on the liquid cartridge.

4. 4. The liquid ejection device according to claim 1, wherein the liquid cartridge has an information storage element portion, and data on the remaining amount of liquid is stored in the information storage element portion.

5. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; an atmosphere opening portion that opens the inside of the head tank to the atmosphere; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a maintenance and recovery mechanism for maintaining and recovering the plurality of nozzles of the droplet ejection head; Equipped with the maintenance and recovery mechanism is capable of switching between a cleaning operation for discharging liquid from the plurality of nozzles of the droplet ejection head and a second cleaning operation for maintaining and recovering the plurality of nozzles of the droplet ejection head without supplying liquid; When the detected liquid level drops to zero, The liquid ejection apparatus according to claim 1, wherein the second cleaning operation can be performed after the head tank is opened to the atmosphere.

6. A notification unit that issues a sensory signal to a user, (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; The liquid ejection device according to claim 5 , wherein when the liquid ejection device is in a state where printing is not possible, a notification is given that the liquid cartridge is empty, or a notification is given to encourage replacement of the liquid cartridge, and the cleaning operation can be performed.

7. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a liquid delivery means for circulating the liquid between the liquid cartridge and the head tank; Equipped with A liquid ejection device, characterized in that the liquid delivery means can be operated even when the detected remaining amount of liquid becomes zero.

8. 8. The liquid ejection apparatus according to claim 7, wherein the liquid delivery means is capable of forward and reverse liquid transfer.

9. a maintenance and recovery mechanism that performs a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head; An alarm unit that issues a sensory signal to a user; Equipped with (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; 9. The liquid ejection device according to claim 7, wherein when the liquid ejection device is in a state where printing is not possible, a notification is given that the liquid cartridge is empty, or a notification is given to encourage replacement of the liquid cartridge, and the cleaning operation can be performed.

10. A droplet ejection head having a plurality of nozzles for ejecting liquid; a head tank for temporarily storing liquid to be supplied to the droplet ejection head; At least one liquid cartridge that contains liquid to be supplied to the head tank; a liquid detection unit that detects the amount of liquid remaining in the liquid cartridge; a maintenance and recovery mechanism that performs a cleaning operation to discharge liquid from the plurality of nozzles of the droplet ejection head; An alarm unit that issues a sensory signal to a user; Equipped with (1) if the detected remaining amount of liquid in the liquid cartridge is equal to or greater than a predetermined amount, the liquid cartridge is placed in a printable state; (2) If the detected remaining amount of liquid in the liquid cartridge is less than a predetermined amount, printing is disabled; When the liquid cartridge is in a state where printing is not possible, a notification is given that the liquid cartridge is empty or a notification is given to prompt the user to replace the liquid cartridge; The liquid ejection apparatus is characterized in that the cleaning operation can be carried out until the remaining amount of liquid in the head tank becomes zero.

11. When the printing is not possible, a notification is given that the liquid cartridge is empty or a notification is given that prompts the user to replace the liquid cartridge.

11. The liquid ejection device according to claim 1, wherein the liquid ejection device is changed to a printable state when a print command is received.

12. When the printing is not possible, a notification is given that the liquid cartridge is empty or a notification is given that prompts the user to replace the liquid cartridge. The liquid ejection apparatus according to claim 11, further comprising a notification for confirming whether or not to change to a printable state.

Images