JP2008105350A - Liquid supply method, liquid supply apparatus, and liquid ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a supply of a plurality of ink in a short time, to enable the ink to be stably supplied, and to enable miniaturization and inexpensiveness. <P>SOLUTION: All of sub tanks are sorted to two or more groups while two or more sub tanks are made one group (for example, a sub tank 60Y and a sub tank 60M are made a group A, and a sub tank 60C and a sub tank 60K are made a group B). At the same time, a feeding priority of the ink to each sub tank in each group is determined. On the basis of a storage amount of the ink, the ink is supplied by the determined priority to each sub tank in each group (for example, the sub tank 60Y is made prior and the sub tank 60M is made posterior in the group A, and the sub tank 60C is made prior and the sub tank 60K is made posterior in the group B). The ink is supplied concurrently to each of all groups (for example, the group A and the group B). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid supply method, a liquid supply apparatus, and a liquid discharge apparatus that supply liquid to a liquid storage container based on detection of the amount of liquid stored in the liquid storage container. The present invention relates to a technique capable of shortening the liquid supply time and simplifying the liquid supply means.

  2. Description of the Related Art Conventionally, as an example of a liquid ejecting apparatus, an ink jet printer that transports a recording medium such as recording paper to a liquid ejecting head and ejects ink (liquid) from a nozzle of the liquid ejecting head to form an image is known. Yes. As a method of supplying ink to the liquid discharge head, a “head integrated type” that supplies ink by arranging the ink integrally with the liquid discharge head and an ink cartridge that is separate from the liquid discharge head are mounted on the ink jet printer. In addition, there is a “head separate type” in which ink in an ink cartridge is supplied to a liquid discharge head by an elastic tube.

  Here, in the case of the “head-separated type” ink supply method, a constant negative pressure is applied to the ink of the liquid ejection head to prevent the ink from leaking from the nozzle, and the ink can be ejected at all times. In order to be able to hold, a sub tank is provided between the ink cartridge and the liquid discharge head. Further, an ink supply pump is installed between the ink cartridge and the sub tank, and ink is supplied from the ink cartridge to the liquid discharge head by this supply pump.

  In the case of a color compatible ink jet printer, an ink cartridge and a sub tank are required for each of the four colors of yellow (Y), magenta (M), cyan (C), and black (K). There are also as many supply pumps as there are ink colors.

  The supply pump is driven by a drive motor so as to suck and discharge ink, and is driven by a pump chamber that sucks and discharges ink by driving the operating unit, and a drive motor that drives the operating unit. It is configured. For this reason, in order to suck and discharge four colors of ink, four drive motors are required, which not only complicates the supply pump, but also increases the size and cost.

Therefore, a technique is known in which the number of drive motors in the supply pump can be reduced. That is, each pump provided in three or more ink supply paths is selectively driven by a single drive source, and the pump to be driven is selected by the rotational power in the first direction input from the drive source. In this technique, the pump selected by the rotational power in the second direction is driven (see, for example, Patent Document 1).
JP 2003-145802 A

In addition, a plurality of pumps can be selectively selected with a single motor by engaging or disengaging the gear connected to the drive shaft of the motor and the intermediate gear by a moving mechanism including a solenoid or the like. There is also known a pump drive device that can be driven in an arbitrary combination and can supply ink selectively and in an arbitrary combination or independently (see, for example, Patent Document 2).
JP 2005-219376 A

  However, in the technique of the above-mentioned Patent Document 1, it is necessary to reverse the motor that is the driving source every time the pump to be driven is selected. Therefore, there is a problem that it takes a long time to supply ink to each ink supply path. Further, in the technique of Patent Document 2, there is a possibility that a difference or the like occurs in ink supply performance due to load fluctuation. In addition, there is a problem that the pump drive device including the moving mechanism becomes large and expensive.

  Therefore, the problem to be solved by the present invention is that a plurality of inks can be supplied in a short time, and moreover, the ink can be stably supplied, and can be reduced in size and inexpensive. It is to be.

The present invention solves the above-described problems by the following means.
The invention according to claim 1, which is one of the present invention, includes a plurality of liquid storage containers capable of storing a liquid therein, and a storage amount capable of detecting a storage amount of the liquid stored in each of the liquid storage containers. A liquid supply method for a liquid supply apparatus comprising a detection means and a liquid supply means capable of supplying a liquid to each of the liquid storage containers, wherein two or more of the liquid storage containers are grouped into all the liquids The storage containers are divided into two or more groups, the liquid supply priority for each of the liquid storage containers in each of the groups is determined, and the liquid supply means detects the amount of liquid detected by the storage amount detection means. Based on the storage amount, for each of the liquid storage containers in each of the groups, the liquid is supplied to each of the liquid storage containers in the determined priority order, and all the groups are handled. Te is characterized by supplying liquid respectively in parallel to each of said liquid storing container.

  The invention according to claim 2, which is another one of the present invention, detects a plurality of liquid storage containers capable of storing liquid therein, and a storage amount of the liquid stored in each of the liquid storage containers. Possible storage amount detection means, liquid supply means capable of supplying a liquid to each of the liquid storage containers, and two or more liquid storage containers as one group, and all the liquid storage containers as two or more groups And a priority order determining unit that determines the priority of liquid supply to each of the liquid storage containers in each group, and storing the liquid detected by the storage amount detection unit by the liquid supply unit. Based on the quantity, for each of the liquid storage containers in each of the groups, supply the liquid to each of the liquid storage containers with the priority determined by the priority determination means, For the group of Te, and supplying the liquid respectively in parallel to each of said liquid storing container.

  Furthermore, the invention according to claim 5, which is another one of the present invention, includes a liquid discharge head for forming an image by discharging liquid from a nozzle, the liquid being stored therein, and the liquid A plurality of liquid storage containers capable of supplying liquid to the ejection head, storage amount detection means capable of detecting the storage amount of the liquid stored in each liquid storage container, and liquid can be supplied to each liquid storage container Liquid supply means and two or more liquid storage containers as one group, all the liquid storage containers are divided into two or more groups, and liquid is supplied to each liquid storage container in each group Priority order determining means for determining the priority order, and each of the groups based on the liquid storage amount detected by the storage amount detection means by the liquid supply means. For each of the liquid storage containers, the liquid is supplied to each of the liquid storage containers in the priority order determined by the priority order determining means, and for each of the groups, A liquid is supplied to the liquid storage container.

(Function)
In the inventions of the first, second, and fifth aspects, two or more liquid storage containers are grouped into one group, all the liquid storage containers are distributed into two or more groups, and each group For each liquid storage container, liquid is supplied to each liquid storage container in the determined priority order, and for all groups, liquid is supplied to each liquid storage container in parallel. Therefore, the liquid is supplied to each group at the same time, and the liquid is supplied in the determined priority order in each group.

  According to the above invention, the liquid can be supplied to each group at the same time, and the liquid can be supplied with the determined priority in each group. Therefore, a plurality of inks can be supplied in a short time. In addition, ink can be stably supplied to each group by a driving source corresponding to the number of groups. Furthermore, since the drive source can be reduced by allocating the liquid storage containers to groups, it is inexpensive and small.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following embodiments, a line head type inkjet printer 10 including a line head 20 (corresponding to the liquid discharge head in the present invention) is taken as an example of the liquid discharge apparatus of the present invention. In the line head 20, nozzles that eject ink (liquid) are linearly arranged at a predetermined pitch over the length in the sheet width direction of the maximum size recording sheet that can be printed. For this reason, a carriage for moving the liquid ejection head in the paper width direction is not required, and noise and vibration during the printing operation are unlikely to occur. During printing, the recording paper moves at a constant speed without being stopped by the conveying means, and ink is continuously ejected from the line head 20 in synchronization therewith, so that the printing time can be shortened. It is. The inkjet printer 10 is compatible with “head-separated type” color, and the ink ejected from the line head 20 is supplied from the ink cartridge 30 through the tube 80.

FIG. 1 is a conceptual diagram showing a line head type ink jet printer 10 of the present embodiment.
As shown in FIG. 1, the ink jet printer 10 includes a line head 20, an ink cartridge 30, a supply pump 40 (corresponding to the liquid supply means in the present invention), a sub tank 60 (corresponding to the liquid storage container in the present invention). , And a suction pump 70, an ink cartridge 30 is provided separately from the line head 20, and the “head separate type” ink supply system is configured to supply ink through a tube 80 that is a liquid flow path. It has become. That is, before the ink is supplied to the line head 20, it passes through the ink cartridge 30, the supply pump 40, and the sub tank 60.

  Here, the line head 20 is configured by laminating a barrier layer on a semiconductor substrate and bonding a nozzle sheet on which nozzles are formed to the barrier layer. A heating resistor is deposited on the semiconductor substrate, and an ink liquid chamber is formed by the semiconductor substrate, the barrier layer, and the nozzle sheet surrounding the heating resistor. The ink liquid chamber has an opening region communicating with the ink flow path, and ink is supplied from the opening region into the ink liquid chamber.

  In order to print on the recording paper using such a line head 20, the heating resistor is driven by a command from the control unit, and ejection energy is applied to the ink contained in the ink liquid chamber, and the ink is ejected from the nozzle. Discharge. At the same time, the recording paper is continuously conveyed while maintaining a position away from the nozzle sheet by a predetermined distance. Then, the ejected ink lands on a predetermined position on the recording paper and printing is performed.

  The ink cartridge 30 is a container that contains four colors of ink of yellow (Y), magenta (M), cyan (C), and black (K). The ink cartridge 30 can be easily detached from the ink jet printer 10. Therefore, it is easy to handle ink, and the user of the inkjet printer 10 can quickly replace the ink cartridge 30 with a new one when the ink in the ink cartridge 30 is insufficient.

  The ink of each color of the ink cartridge 30 attached to the ink jet printer 10 is sent to the sub tank 60 by the supply pump 40. That is, the supply pump 40 can inhale the ink of the corresponding color from the ink cartridge 30 as necessary, and discharge it toward the sub tank 60. Therefore, if the supply pump 40 is driven, ink of each color is supplied from the ink cartridge 30 to the sub tank 60 through the tubes 80 of the four liquid distribution paths.

  The sub tank 60 temporarily stores ink during the ink supply process. However, the sub tank 60 is not a simple storage tank, but, as will be described later, an on-off valve 65d for adjusting the flow rate of ink supplied to the line head 20, A liquid amount sensor 61c (corresponding to the storage amount detection means in the present invention) for detecting the remaining amount, a filter 61d for removing bubbles and foreign matters mixed in the ink, and the like are incorporated. For this reason, functions such as pressure adjustment in the line head 20, detection of the remaining amount of ink, removal of bubbles and foreign matters are provided. For example, a liquid amount sensor 61 c provided so as to come into contact with ink in the sub tank 60. When a decrease in ink is detected, the ink is supplied from the ink cartridge 30 to the sub tank 60 by the supply pump 40 corresponding to the ink of that color. Therefore, in the inkjet printer 10 of this embodiment, the various states of the line head 20 can be best maintained by stably supplying ink from the sub tank 60 to the line head 20.

  Further, the sub tank 60 is installed at a position lower than the line head 20 so that the meniscus of the nozzle for ejecting ink can be maintained. In other words, by setting the ink ejection surface of the line head 20 (the surface of the nozzle sheet on the ink ejection side) to be higher in the vertical direction than the sub tank 60, the ink in the ink liquid chamber has a certain amount based on the water head difference. Negative pressure is applied. Therefore, it is possible to prevent the ink from leaking from the nozzles and to always maintain a state where ink can be ejected.

  Furthermore, the suction pump 70 is for sucking ink from the line head 20 at the time of initial ink filling or maintenance. In other words, the ink is supplied to the line head 20 from the supply port 21a, but each ink containing bubbles and foreign matter can be maintained so that the bubbles and foreign matters in the line head 20 can be removed and normal ink ejection can be maintained. A suction pump 70 is connected to the discharge port 21b opposite to the supply port 21a in order to suck from the line head 20 and discharge it.

  The ink discharge operation by the suction pump 70 is set to be arbitrary or periodically, and the cleaning in the line head 20 can be efficiently performed. Note that the suction pump 70 can select and discharge only the ink having a defect such as mixing of bubbles, and can reduce wasteful ink consumption due to cleaning.

  As described above, the ink jet printer 10 of the present embodiment is provided with the ink cartridge 30 and the sub tank 60 for each of the four colors Y (yellow), M (magenta), C (cyan), and K (black). ing. The sub-tank 60 detects the remaining amount of ink for each ink, so that the optimum ink can be supplied with a minimum amount of ink consumption. Therefore, not only high-quality printing but also large-scale printing accompanying the recent improvement in printing speed can be supported.

FIG. 2 is a cross-sectional view showing the sub tank 60 in the inkjet printer 10 of the present embodiment shown in FIG. There are four sub-tanks 60 corresponding to four colors of ink of Y (yellow), M (magenta), C (cyan), and K (black), and each has the same configuration.
As shown in FIG. 2, the sub tank 60 includes a first liquid chamber 61 that can store ink therein, a second liquid chamber 62 that can discharge ink stored therein, and a first liquid chamber 61. A partition wall 63 for partitioning from the second liquid chamber 62, an opening 64 formed in the partition wall 63, and a pressure adjusting valve 65 for opening and closing the opening 64 are provided.

  Here, the first liquid chamber 61 includes a supply port 61a that receives ink supplied by the supply pump 40 (see FIG. 1), and an atmosphere communication port 61b for communicating the inside of the first liquid chamber 61 and the atmosphere. The liquid amount sensor 61c detects the remaining amount of ink in the first liquid chamber 61, and the filter 61d removes bubbles and foreign matters mixed in the ink. A tube 81 from the supply pump 40 is connected to the supply port 61a, and a tube 82 having the other end opened is connected to the atmosphere communication port 61b. An atmosphere communication valve 66 is provided in the middle of the tube 82. Is attached.

  At normal times, the atmospheric communication valve 66 is open, and the atmospheric pressure in the first liquid chamber 61 is kept equal to the atmospheric pressure. Further, the ink supplied from the supply pump 40 flows in through the supply inlet 61 a and is stored in the first liquid chamber 61. Furthermore, since the electrode of the liquid amount sensor 61c is exposed on the top surface of the first liquid chamber 61, and the liquid level of the stored ink can be detected, the liquid amount sensor 61c allows the ink in the first liquid chamber 61 to be detected. When the decrease is detected, ink is supplied from the ink cartridge 30 (see FIG. 1) to the first liquid chamber 61 by the supply pump 40 corresponding to the ink of that color. The liquid amount sensor 61c only detects whether or not the amount of ink stored is full, but may be any sensor that can detect at least the full amount.

  Further, a filter 61d is installed at an intermediate portion in the first liquid chamber 61 so that all ink passes through the filter 61d from the top to the bottom. Therefore, bubbles and foreign matters mixed in the ink are removed by the filter 61d, so that the ink can be stably ejected by the line head 20 (see FIG. 1).

  On the other hand, the second liquid chamber 62 is partitioned from the first liquid chamber 61 by a partition wall 63 provided downstream of the filter 61 d in the first liquid chamber 61. The partition wall 63 is formed with an opening 64 for allowing the ink stored in the first liquid chamber 61 to flow out toward the second liquid chamber 62. Therefore, the ink from which bubbles and foreign matters are removed in the first liquid chamber 61 can flow into the second liquid chamber 62 through the opening 64.

  Here, a pressure adjusting valve 65 for opening and closing the opening 64 is installed in the opening 64 formed in the partition wall 63. The pressure adjusting valve 65 is constituted by a valve shaft 65a, an opening / closing spring 65b, a diaphragm 65c, and an opening / closing valve 65d, and adjusts the flow rate of ink discharged from the discharge port 62a of the second liquid chamber 62 to thereby adjust the line head. It plays a role of making the ink pressure in the 20 ink chambers substantially constant.

  Accordingly, the ink that flows into the second liquid chamber 62 through the opening 64 and is stored is sent out toward the line head 20 with the ink flow rate adjusted. That is, a tube 83 directed to the line head 20 is connected to the discharge port 62a, and the ink in the second liquid chamber 62 is supplied to the ink liquid chamber of the line head 20 so that the ink pressure becomes substantially constant. Will be.

  As described above, the ink of each color of Y (yellow), M (magenta), C (cyan), and K (black) of the ink cartridge 30 is supplied to the line head 20 via the sub tank 60. Ink supply to each sub tank 60 corresponding to each color ink is performed by the supply pump 40 based on the ink storage amount detected by the liquid amount sensor 61c.

FIG. 3 is a perspective view showing the supply pump 40 in the inkjet printer 10 of the present embodiment shown in FIG. The suction pump 70 has the same configuration and is shared with the supply pump 40.
As shown in FIG. 3, the supply pump 40 corresponds to inks of four colors Y (yellow), M (magenta), C (cyan), and K (black). A first pump chamber 41 that sucks and discharges yellow ink, a second pump chamber 42 that sucks and discharges M (magenta) ink, and a third pump that sucks and discharges C (cyan) ink. A pump chamber 43 and a fourth pump chamber 44 for sucking and discharging K (black) ink are provided.

  And the 1st operation part (not shown) of the 1st pump chamber 41 and the 2nd operation part (not shown) of the 2nd pump chamber 42 are equivalent to the 1st drive motor 45 (the drive motor in the present invention). The third actuating part (not shown) of the third pump chamber 43 and the fourth actuating part (not shown) of the fourth pump chamber 44 are driven by the second drive motor 46 (drive in the present invention). Driven by a motor). Therefore, Y (yellow) and M (magenta) ink can be individually sucked and discharged by the first drive motor 45, and C (cyan) and K (black) can be individually discharged by the second drive motor 46. The ink can be sucked and discharged. Each component such as the first drive motor 45 and the second drive motor 46 is fixed to a hard resin case 59 by screwing or fitting.

4 is an exploded view of the supply pump 40 shown in FIG. 3, and is a perspective view showing a state in which the first drive motor 45 and the second drive motor 46 are removed.
5 is an exploded view of the supply pump 40 shown in FIG. 3, and is a perspective view showing a state in which the first operating part 47, the second operating part 48, the third operating part 49, and the fourth operating part 50 are exposed. FIG.
FIG. 6 is an exploded view of the supply pump 40 shown in FIG. 3, and shows a state in which the first pump chamber 41, the second pump chamber 42, the third pump chamber 43, and the fourth pump chamber 44 are removed. It is a perspective view.

  As shown in FIG. 4, a motor support plate 59a is fitted and fixed to the case 59, and the first drive motor 45 and the second drive motor 46 are attached to the motor support plate 59a. When the motor support plate 59a is removed, the first operating part 47, the second operating part 48, the third operating part 49, and the fourth operating part 50 are exposed as shown in FIG.

  Here, the first operating part 47 sucks and discharges Y (yellow) ink in the first pump chamber 41, and the second operating part 48 sets M (magenta) ink in the second pump chamber 42. The third operating part 49 sucks and discharges C (cyan) ink in the third pump chamber 43, and the fourth operating part 50 controls the fourth pump chamber 44. K (black) ink is sucked and discharged.

  The first drive motor 45 (see FIG. 4) drives the first operating unit 47 and the second operating unit 48 in common, and the second drive motor 46 (see FIG. 4) has the third operating unit 49 and The fourth operating unit 50 is driven in common. That is, the power of the first drive motor 45 is transmitted to the first operating part 47 or the second operating part 48 by the first pendulum gear 51 (corresponding to the power switching mechanism in the present invention) and transmitted. The power of 46 is switched and transmitted to the third operating part 49 or the fourth operating part 50 by the second pendulum gear 52 (corresponding to the power switching mechanism in the present invention).

  Moreover, the 1st pump chamber 41, the 2nd pump chamber 42, the 3rd pump chamber 43, and the 4th pump chamber 44 are each arrange | positioned adjacently, and become an integrated pump unit. The pump unit composed of the first pump chamber 41 to the fourth pump chamber 44 can be removed from the case 59 as shown in FIG. Then, on the pump unit side, the first piston 47a of the first operating portion 47 (see FIG. 5), the second piston 48a of the second operating portion 48 (see FIG. 5), and the third operating portion 49 (see FIG. 5). The third piston 49a and the fourth piston 50a of the fourth operating portion 50 (see FIG. 5) remain, and are separated from the first pendulum gear 51 and the second pendulum gear 52. Therefore, the supply pump 40 has a structure that can be easily disassembled and assembled.

FIG. 7 is a perspective view and an operation diagram showing the pump units (first pump chamber 41, second pump chamber 42, third pump chamber 43, and fourth pump chamber 44) of the supply pump 40 shown in FIG.
As shown in FIG. 7A, the pump unit in which the first pump chamber 41 to the fourth pump chamber 44 are integrated includes a first exhaust chamber corresponding to the first pump chamber 41 to the fourth pump chamber 44. An outlet 41a, a second outlet 42a, a third outlet 43a, and a fourth outlet 44a are provided, and a tube 81 (see FIG. 2) for circulating ink is connected to the sub tank 60 (see FIG. 2). The On the opposite side, although not shown, a first suction port to a fourth suction port for receiving ink of the ink cartridge 30 (see FIG. 1) are provided.

  Here, the first pump chamber 41 to the fourth pump chamber 44 all have the same structure, and a diaphragm, a spring, a check valve, etc. (not shown) are attached to the inside of each of the first pump chamber 41 and the first piston 47a. Ink can be sucked and discharged by reciprocating the fourth piston 50a. That is, as shown in FIG. 7B, if the first piston 47a is pushed in, ink is discharged from the first discharge port 41a, and if the first piston 47a is pulled out as shown in FIG. Ink is sucked from one suction port 41b. The ink suction and discharge operations by the second piston 48a, the third piston 49a, and the fourth piston 50a are exactly the same.

FIG. 8 is a front view showing an operation state of the supply pump 40 shown in FIG. 3 and shows a state in which ink is discharged from the first pump chamber 41.
FIG. 9 is a front view showing an operating state of the supply pump 40 shown in FIG. 3 and shows a state in which ink is discharged from the second pump chamber 42.

  As shown in FIGS. 8 and 9, the first pump chamber 41 is formed with a first discharge port 41a, and a first piston 47a protrudes. And the 1st piston 47a comprises the 1st operation part 47 (refer to Drawing 5) with the 1st piston gear 47b, a crank mechanism operates by rotation of the 1st piston gear 47b, and the 1st piston 47a goes up and down. Reciprocate. Therefore, if the first piston gear 47b is rotated, Y (yellow) ink is discharged from the first discharge port 41a.

  Similarly, if the second piston gear 48b is rotated, the second piston 48a reciprocates up and down, M (magenta) ink is discharged from the second discharge port 42a of the second pump chamber 42, and the third piston gear. If 49b is rotated, the third piston 49a reciprocates up and down, C (cyan) ink is discharged from the third discharge port 43a of the third pump chamber 43, and if the fourth piston gear 50b is rotated, the third piston 49a is rotated. The four pistons 50 a reciprocate up and down, and K (black) ink is discharged from the fourth discharge port 44 a of the fourth pump chamber 44.

  Here, the first piston gear 47b and the second piston gear 48b are aligned on a straight line. And between the 1st piston gear 47b and the 2nd piston gear 48b, the 1st sun gear 51a attached to the 1st drive shaft 45a of the 1st drive motor 45 (refer to Drawing 3), and the 1st sun gear 51a At the same time, a first planetary gear 51b constituting the first pendulum gear 51 (see FIG. 5) is arranged.

  Therefore, if the first drive motor 45 (see FIG. 3) is rotated clockwise (forward rotation), the first sun gear 51a rotates clockwise in accordance with the clockwise rotation of the first drive shaft 45a. As shown in FIG. 8, the first planetary gear 51b is engaged with the first piston gear 47b. As a result, the power of the first drive motor 45 is transmitted to the first piston gear 47b, and the first piston 47a reciprocates up and down, and the ink in the first pump chamber 41 is discharged.

  On the other hand, if the first drive motor 45 (see FIG. 3) is rotated counterclockwise (reversely rotated), the first sun gear 51a rotates counterclockwise as the first drive shaft 45a rotates counterclockwise. As shown in FIG. 9, the first planetary gear 51b is engaged with the second piston gear 48b. As a result, the power of the first drive motor 45 is transmitted to the second piston gear 48b, the second piston 48a reciprocates up and down, and the ink in the second pump chamber 42 is discharged.

  Similarly, a second sun gear 52a attached to the second drive shaft 46a of the second drive motor 46 (see FIG. 3) is disposed between the third piston gear 47b and the second piston gear 48b aligned in a straight line. A second planetary gear 52b is arranged. Therefore, when the second drive motor 46 is rotated clockwise (forward rotation), the second planetary gear 52b is engaged with the third piston gear 49b, and the ink in the third pump chamber 43 is discharged. If the second drive motor 46 is rotated counterclockwise (reverse rotation), the second planetary gear 52b is engaged with the fourth piston gear 50b, and the ink in the fourth pump chamber 44 is discharged.

  As described above, the supply pump 40 in the inkjet printer 10 according to the present embodiment is configured so that the first operating motor 47 (the first piston 47a and the first piston gear 47b) and the second actuator 40 are rotated by the forward rotation or the reverse rotation of the first drive motor 45. The first pendulum gear 51 (first sun gear 51a, first planetary gear 51b) that mechanically displaces between the operating portion 48 (second piston 48a, second piston gear 48b) serves as a power switching mechanism, and the first Since the power of the drive motor 45 is switched and transmitted to the first operating part 47 or the second operating part 48, the first operating part 47 and the second operating part 48 are commonly driven by one first drive motor 45. Can do.

  Further, by the forward or reverse rotation of the second drive motor 46, the third operating part 49 (third piston 49a, third piston gear 49b) and the fourth operating part 50 (fourth piston 50a, fourth piston gear 50b). The second pendulum gear 52 (second sun gear 52a, second planetary gear 52b) that mechanically displaces between the first drive motor 46 and the second switch gear 46 serves as a power switching mechanism. Since the transmission is switched to the unit 50, the third operating unit 49 and the fourth operating unit 50 can be commonly driven by one second drive motor 46.

  Therefore, the first pump chamber 41, the second pump chamber 42, the third pump chamber 43, and the first pump chamber 41 corresponding to four colors of ink of Y (yellow), M (magenta), C (cyan), and K (black) are used. Even if a drive motor is not disposed in each of the four pump chambers 44, only two (half) of the first drive motor 45 and the second drive motor 46 can be used for the first pump chamber 41 to the fourth pump chamber 44. Ink can be discharged. Then, by selecting ON / OFF of the first drive motor 45 and the second drive motor 46 and forward / reverse rotation, any one of the first pump chamber 41 to the fourth pump chamber 44 is selected to suck and discharge ink. It can be carried out.

  Further, ink can be discharged from the four pump chambers 44 from the first pump chamber 41 by only two of the first drive motor 45 and the second drive motor 46, so that each of the four drive motors has a drive motor. Compared with the case where it arrange | positions, a layout with a much more efficient efficiency is attained, and the supply pump 40 can be made compact by arrange | positioning the 4th pump chamber 44 from the 1st pump chamber 41 approaching.

  Furthermore, the number of parts including the drive motor can be reduced and the size can be reduced, and the parts cost and the manufacturing cost can be greatly reduced. Furthermore, it becomes easy to arrange the first discharge port 41a to the fourth discharge port 44a of the first pump chamber 41 to the fourth pump chamber 44 so as to be aligned in a straight line, and not only the pipe layout is orderly, but also the tube The length of 81 (see FIG. 2) can be made common, and work efficiency can be improved and costs can be reduced.

  In such a configuration, the inkjet printer 10 of the present embodiment includes four sub tanks 60 (corresponding to four colors of inks of Y (yellow), M (magenta), C (cyan), and K (black)). The sub-tank 60Y, the sub-tank 60M, the sub-tank 60C, and the sub-tank 60K are respectively assigned to two groups. That is, the sub-tank 60Y to which Y (yellow) ink is supplied from the first pump chamber 41 of the supply pump 40 and the sub-tank 60M to which M (magenta) ink is supplied from the second pump chamber 42 constitute group A. The sub-tank 60C to which C (cyan) ink is supplied from the third pump chamber 43 and the sub-tank 60K to which K (black) ink is supplied from the fourth pump chamber 44 constitute group B.

  In this way, the assignment of two or more sub-tanks 60 as one group and all the sub-tanks 60 as two or more groups is performed by a command from the control unit as the priority order determining means. The priority order determining means determines the priority order of ink supply to each sub tank 60 in each group. In the inkjet printer 10 of this embodiment, Y (yellow) is the first in group A, and M (magenta). After that, in group B, C (cyan) comes first and K (black) comes after.

  By performing such group assignment and priority determination, the ink jet printer 10 of this embodiment can manage and control ink supply in units of groups. That is, the ink jet printer 10 of the present embodiment is configured so that the sub-tank 60Y and the sub-tank 60M in the group A and the sub-tank 60M in the group A are based on the ink storage amount detected by the liquid amount sensor 61c by the supply pump 40. Ink is supplied to the sub tank 60C and the sub tank 60K with the priority determined by the priority determining means, and the ink is supplied to the group A and the group B in parallel.

FIG. 10 is a flowchart illustrating an ink supply method in the inkjet printer 10 of the present embodiment.
As shown in FIG. 10, when a print command is input in step S1 after the start, the amount of ink stored in the sub tank 60 shown in FIG. 2 is detected by the liquid amount sensor 61c.

  Here, the amount of ink stored is detected in step S2 following step S1, but in group A, detection is performed for the sub-tank 60Y that has the highest priority (step S2-A), and in group B, the priority is detected. Is detected for the sub-tank 60C which is first (step S2-B). Step S2-A and step S2-B are executed simultaneously.

  Ink is replenished in the next step S3. That is, if it is detected in step S2-A that the sub tank 60Y is not full, the first drive motor 45 is rotated forward in the next step S3-A to drive the first pump chamber 41, and Y Replenish the (yellow) ink until it is full. If it is detected in step S2-B that the sub tank 60C is not full, the second drive motor 46 is rotated forward in the next step S3-B to drive the third pump chamber 43, and C Supply (cyan) ink until it is full.

  Subsequently, in step S4, the remaining ink storage amount is detected, and ink is supplied in the next step S5. That is, in group A, detection is performed for sub-tank 60M having a later priority (step S4-A), and in group B, detection is performed for sub-tank 60K having a later priority (step S4-B). When it is detected in step S4-A that the sub tank 60M is not full, in the next step S5-A, the first drive motor 45 is reversely rotated to drive the second pump chamber 42, and M Supply (magenta) ink until it is full. On the other hand, if it is detected in step S4-B that the sub tank 60K is not full, the second drive motor 46 is reversely rotated in the next step S5-B to drive the fourth pump chamber 44. Supply (black) ink until it is full.

  In this way, ink is replenished in parallel to the groups A and B, and it is determined whether or not a predetermined time has passed in the next step S6. In the next step S7, it is confirmed that the sub tank 60Y and sub tank 60M belonging to group A and the sub tank 60C and sub tank 60K belonging to group B are all full, and the printing operation is executed in step S8. And end. If the full state of group A and group B cannot be confirmed in step S7, the process branches to step S9, and an error is displayed including the possibility that the ink cartridge 30 has run out.

  Therefore, in the inkjet printer 10 of the present embodiment, ink is supplied in units of groups, and ink can be supplied to the groups A and B at the same time. Since the ink can be supplied by applying the ink, the ink is accurately supplied in a short time to all the sub tanks 60 that need to be supplied with the ink. As a result, not only the waiting time until execution of the printing operation is shortened, but also printing can be performed with all the sub-tanks 60 in a full state, and it is ensured that the ink runs out during execution of the printing operation. Can be prevented.

  In addition, since the amount of ink stored is detected for all the sub tanks 60 and ink is supplied only to the sub tanks 60 that need to be supplied with ink, the ink is not wasted. Furthermore, since the first drive motor 45 of the supply pump 40 is shared within the group A and the second drive motor 46 is shared within the group B, the same number of pump chambers (the first pump chamber 41, the second pump chamber 41 and the second pump tank 46) are shared. For the pump chamber 42, the third pump chamber 43, and the fourth pump chamber 44), it is only necessary to have the same number of drive motors (first drive motor 45, second drive motor 46) as the group. Costs can be significantly reduced.

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to embodiment mentioned above, For example, the following various deformation | transformation is possible.
(1) In the present embodiment, two sub-tanks 60 are divided into two groups, two at a time. However, if there are two or more groups with two or more sub-tanks 60 as one group, the number of sub-tanks 60 Depending on etc., it may be distributed in any way. In this embodiment, the ink is supplied before the printing operation is performed. However, the ink storage amount may be detected and the ink supplied after the printing operation is completed.

  (2) In the supply pump 40 of the present embodiment, the total number of pump chambers in each group is limited to two or less, but if other types of liquid supply means are employed, two or more pump chambers in one group are used. It is also possible to increase it. The liquid supply means may be a suction type or a pressure type.

  (3) In the present embodiment, the line head type inkjet printer 10 including the line head 20 corresponding to the print width is taken as an example of the liquid ejecting apparatus. However, the liquid ejecting apparatus is not limited to the line head type and moves in the width direction of the recording paper. Alternatively, a serial head method for performing printing may be used. Further, the present invention can be widely applied to other liquid ejecting apparatuses that eject various liquids, and may be, for example, a liquid ejecting apparatus that ejects dye to a dyed product.

1 is a conceptual diagram showing a line head type ink jet printer of an embodiment. FIG. It is sectional drawing which shows the sub tank in the inkjet printer of this embodiment. It is a perspective view which shows the supply pump in the inkjet printer of this embodiment. FIG. 4 is an exploded view of the supply pump shown in FIG. 3 and is a perspective view showing a state in which a first drive motor and a second drive motor are removed. FIG. 4 is an exploded view of the supply pump shown in FIG. 3, and is a perspective view showing a state in which a first operating part, a second operating part, a third operating part, and a fourth operating part are exposed. FIG. 4 is an exploded view of the supply pump shown in FIG. 3, and is a perspective view showing a state where a first pump chamber, a second pump chamber, a third pump chamber, and a fourth pump chamber are removed. It is the perspective view and operation | movement figure which show the pump unit (a 1st pump chamber, a 2nd pump chamber, a 3rd pump chamber, and a 4th pump chamber) of the supply pump shown in FIG. FIG. 4 is a front view showing an operation state of the supply pump shown in FIG. 3 and shows a state in which ink is discharged from the first pump chamber. FIG. 4 is a front view showing an operation state of the supply pump shown in FIG. 3 and shows a state in which ink is discharged from the second pump chamber. 4 is a flowchart illustrating an ink supply method in the ink jet printer according to the embodiment.

Explanation of symbols

10 Inkjet printer (liquid ejection device)
20 line head (liquid discharge head)
40 Supply pump (liquid supply means)
41 1st pump chamber 42 2nd pump chamber 43 3rd pump chamber 44 4th pump chamber 45 1st drive motor 46 2nd drive motor 47 1st operation part 48 2nd operation part 49 3rd operation part 50 4th operation part 51 First pendulum gear (power switching mechanism)
52 Second pendulum gear (power switching mechanism)
60, 60Y, 60M, 60C, 60K Sub tank (liquid storage container)
61c Liquid quantity sensor (reserved quantity detection means)

Claims (6)

A plurality of liquid storage containers capable of storing liquid therein;
A storage amount detecting means capable of detecting a storage amount of the liquid stored in each of the liquid storage containers;
A liquid supply method of a liquid supply device comprising: a liquid supply means capable of supplying a liquid to each of the liquid storage containers,
Two or more liquid storage containers are grouped into one group, all the liquid storage containers are distributed to two or more groups, and the priority of liquid supply to each of the liquid storage containers in each group is determined. ,
Based on the liquid storage amount detected by the storage amount detection means by the liquid supply means, the liquid storage containers in the group are assigned with the determined priority order. A liquid supply method comprising: supplying a liquid to each of the liquid storage containers in parallel to each of the groups. A plurality of liquid storage containers capable of storing liquid therein;
A storage amount detecting means capable of detecting a storage amount of the liquid stored in each of the liquid storage containers;
Liquid supply means capable of supplying liquid to each of the liquid storage containers;
Two or more liquid storage containers are grouped into one group, all the liquid storage containers are distributed to two or more groups, and the priority of liquid supply to each of the liquid storage containers in each group is determined. A priority determination means, and
Based on the liquid storage amount detected by the storage amount detection means by the liquid supply means, the priority order determined by the priority order determination means for each of the liquid storage containers in each group. The liquid supply device is characterized in that a liquid is supplied to each of the liquid storage containers, and the liquid is supplied to each of the liquid storage containers in parallel to all the groups. The liquid supply apparatus according to claim 2, wherein
The liquid supply means includes
A pump chamber that sucks and discharges liquid by driving an operating unit;
A drive motor for driving the operating part,
The pump chamber has the same number as the liquid storage container,
The number of the drive motors is the same as the number of the groups. The liquid supply apparatus according to claim 2, wherein
The liquid supply means includes
A first pump chamber that sucks and discharges the first liquid by driving the first working unit;
A second pump chamber that sucks and discharges the second liquid by driving the second working unit;
One drive motor that drives the first operating unit and the second operating unit in common;
A power switching mechanism for switching and transmitting the power of the drive motor to the first operating part or the second operating part based on the priority order determined by the priority order determining means;
The liquid supply device, wherein the power switching mechanism is a pendulum gear that mechanically displaces between the first operating unit and the second operating unit by forward rotation or reverse rotation of the drive motor. A liquid ejection head for ejecting liquid from a nozzle to form an image;
A plurality of liquid storage containers capable of storing liquid inside and capable of supplying liquid to the liquid discharge head;
A storage amount detecting means capable of detecting a storage amount of the liquid stored in each of the liquid storage containers;
Liquid supply means capable of supplying liquid to each of the liquid storage containers;
Two or more liquid storage containers are grouped into one group, all the liquid storage containers are distributed to two or more groups, and the priority of liquid supply to each of the liquid storage containers in each group is determined. A priority determination means, and
Based on the liquid storage amount detected by the storage amount detection means by the liquid supply means, the priority order determined by the priority order determination means for each of the liquid storage containers in each group. A liquid ejecting apparatus comprising: supplying a liquid to each of the liquid storage containers, and supplying the liquid to each of the liquid storage containers in parallel to all the groups. The liquid ejection apparatus according to claim 5, wherein
The liquid discharge device, wherein the storage amount detection unit detects a storage amount of liquid stored in each of the liquid storage containers before or after image formation by the liquid discharge head.

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