JP2010069845A - Liquid feeding apparatus, printer, and controlling method for liquid feeding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid feeding apparatus which can favorably perform the replenishment of a liquid while ensuring a favorable throughput, and in addition, has a simple structure, can be miniaturized and can reduce costs, to provide a printer, and to provide a controlling method for the liquid feeding apparatus. <P>SOLUTION: This inkjet printer 1 includes an ink pump 34 which replenishes ink from an ink cartridge 17 to a subsidiary tank 45 through the movement of a carriage 23. The inkjet printer 1 includes: an operation means 112 which calculates an ink residual amount in the subsidiary tank 45 and an estimated ink amount to be discharged from an inkjet head according to a printing command; a comparing means 113 which determines whether the ink residual amount in the subsidiary tank 45 is less than the estimated ink amount or not; and a CPU 115 which regards a difference between the estimated ink amount and the ink residual amount as an ink shortage amount, and sets the moving amount of the carriage 23 for replenishing only the ink shortage amount to the subsidiary tank 45. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid supply apparatus that supplies liquid in a main tank to a head via a sub tank, a printing apparatus, and a control method for the liquid supply apparatus.

An example of the liquid supply apparatus is an apparatus that is incorporated in a printer connected to a personal computer or the like and supplies ink as a liquid to a print head.
Such a liquid supply apparatus includes an ink supply unit connected to the first ink tank in accordance with the movement operation of the recording head having the first ink tank to the home position, and an ink remaining amount in the first ink tank. It is known that a detection means and a fixed second ink tank are provided, and ink is replenished from the second ink tank to the first ink tank by the ink supply means when the ink remaining amount becomes a predetermined value or less at the home position. (For example, refer to Patent Document 1).
Also, a recording head having a sub tank, a main tank for holding ink to be supplied to the sub tank, a replenishing means for replenishing ink from the main tank to the sub tank, and a computing means for counting the amount of ink discharged and discharged from the head section And a replenishment control means for controlling the replenishment amount of ink according to the calculation result (see, for example, Patent Document 2).

JP 7-125242 A JP-A-11-227220

By the way, in the above-described apparatus in which the ink is supplied by the pump means after the head is moved to the standby position, it takes time to fill the sub tank with ink when the ink is supplied to the sub tank. In particular, there is a concern that throughput may be reduced by replenishing ink during continuous printing.
Further, the above apparatus requires complicated pumping means such as ink feeding means and replenishing means having separate drive sources, which increases the cost and requires a large installation space for the pumping means. Also, the size of the apparatus will be increased.
In addition, there is a risk of drying, adhesion of foreign matter, or deterioration in sealing performance at the connection between the pump means and the tank on the head side, and it is difficult to ensure reliability.

  Accordingly, an object of the present invention is to provide a highly reliable liquid supply that can satisfactorily replenish liquid while ensuring good throughput, and that can be reduced in size and cost with a simple structure. It is an object to provide a control method for an apparatus, a printing apparatus, and a liquid supply apparatus.

The liquid supply apparatus according to the present invention capable of solving the above-described problems includes a main tank in which liquid is stored in a sealed capacity-variable storage unit,
A sub tank in which liquid is replenished from the main tank;
A head capable of discharging liquid supplied from the sub tank;
A carriage on which the head and the sub tank are mounted and movable;
A liquid supply device having a replenishment mechanism for replenishing liquid supplied to the head from the main tank to the sub tank by movement of the carriage,
A calculation unit that calculates a remaining liquid amount in the sub tank and a predicted liquid amount to be discharged from the head based on a discharge command;
A determination unit that determines whether the liquid remaining amount in the sub tank is less than the predicted liquid amount;
When the remaining liquid amount in the sub-tank is less than the predicted liquid amount, the difference between the predicted liquid amount and the remaining liquid amount is set as a liquid shortage amount, and the liquid shortage amount is replenished to the sub tank. And a setting unit for setting the movement amount of the carriage.

According to the liquid supply apparatus having this configuration, when the liquid remaining amount in the sub tank and the predicted liquid amount to be discharged from the head by the discharge command are calculated, and the liquid remaining amount in the sub tank is less than the predicted liquid amount Since the difference between the predicted liquid amount and the remaining liquid amount is set as the liquid shortage amount, and the carriage movement amount is set to replenish the liquid shortage amount to the sub tank, the interruption of the printing process due to the liquid replenishment operation can be suppressed as much as possible. . Thereby, the liquid can be replenished satisfactorily while ensuring a good throughput.
In addition, since a separate drive source for replenishing liquid is not required and the flow path is not connected when replenishing liquid, the structure can be reduced in size and cost can be reduced with a simple structure. Can be improved.

In the liquid supply apparatus according to the aspect of the invention, it is preferable that the calculation unit calculates a liquid discharge amount discharged from the head as the predicted liquid amount before a periodic maintenance process involving a liquid supply operation to the sub tank.
According to the liquid supply apparatus of this configuration, the liquid discharge amount discharged from the head is calculated as the predicted liquid amount until the periodic maintenance process with the liquid replenishment operation to the sub tank, so that the liquid remaining amount in the sub tank is regularly When the amount of liquid is less than the predicted liquid amount until a typical maintenance process, the difference between the predicted liquid amount and the remaining liquid amount is set as the liquid shortage amount, and the carriage movement amount to replenish the sub tank with the liquid shortage amount is set. The interruption of the printing process due to the liquid supply operation until the maintenance process can be suppressed as much as possible. Thereby, the liquid can be replenished satisfactorily while ensuring a good throughput.

In the liquid supply apparatus according to the aspect of the invention, when the remaining amount of liquid in the main tank is less than a predetermined value, the setting unit includes a long time mode in which the liquid supply operation is long and a low speed in which the liquid supply operation is slow. It is preferable to set at least one of the modes.
According to the liquid supply apparatus having this configuration, when the remaining amount of liquid in the main tank is less than a predetermined value and the negative pressure of the main tank becomes large, the long time mode of the liquid replenishment operation and the speed of the liquid replenishment operation are slow. Since at least one of the low-speed modes is set, it is possible to reliably supply liquid from the main tank in a state where the remaining amount of liquid is small to the sub tank. In addition, the time for the liquid replenishment operation when the remaining amount of liquid in the main tank is equal to or greater than a predetermined value can be shortened, and the speed of the liquid replenishment operation can be increased.
That is, it is possible to reliably supply the liquid to the sub tank while greatly increasing the efficiency of the throughput, and it is possible to reduce the size and the cost with a simple structure.

The printing apparatus of the present invention is a printing apparatus that performs printing processing by ejecting ink from the head to a conveyed medium,
As a device for supplying ink to the head, any one of the liquid supply devices of the present invention is provided.

  According to the printing apparatus having this configuration, the throughput efficiency can be improved, and the ink can be reliably supplied to the sub tank, so that the printing can be efficiently performed on the medium.

The method for controlling a liquid supply apparatus according to the present invention includes a main tank in which liquid is stored in a sealed variable capacity storage unit, a sub tank in which liquid is supplied from the main tank, and discharge of liquid supplied from the sub tank. A liquid having a movable head, a carriage on which the head and the sub tank are mounted and movable, and a replenishment mechanism for replenishing the liquid supplied to the head from the main tank to the sub tank by movement of the carriage A control method for a supply device,
A calculation step of calculating a remaining amount of liquid in the sub tank and a predicted liquid amount to be discharged from the head based on a discharge command;
A determination step of determining whether or not the remaining liquid amount in the sub-tank is less than the predicted liquid amount;
When the remaining liquid amount in the sub-tank is less than the predicted liquid amount, the difference between the predicted liquid amount and the remaining liquid amount is set as a liquid shortage amount, and the liquid shortage amount is replenished to the sub tank. And a setting step for setting the amount of movement of the carriage.

According to the control method of the liquid supply apparatus, when the remaining amount of liquid in the sub tank and the predicted amount of liquid discharged from the head according to the discharge command are calculated, the remaining amount of liquid in the sub tank is less than the predicted amount of liquid. In addition, since the difference between the predicted liquid amount and the remaining liquid amount is set as the liquid shortage amount, and the carriage movement amount is set to replenish the sub tank with the liquid shortage amount, the interruption of the printing process due to the liquid replenishment operation can be minimized. it can. Thereby, the liquid can be replenished satisfactorily while ensuring a good throughput.
In addition, a separate drive source for the liquid replenishing pump means is not required, and the flow path is not connected at the time of liquid replenishment, so that a simple structure can be reduced in size and cost. Also, the reliability can be improved.

In the method for controlling a liquid supply apparatus according to the present invention, in the calculation step, the liquid discharge amount discharged from the head is calculated as the predicted liquid amount before a periodic maintenance process involving a liquid supply operation to the sub tank. Is preferred.
According to the control method of the liquid supply apparatus, the liquid discharge amount discharged from the head is calculated as the predicted liquid amount until the periodic maintenance process with the liquid replenishment operation to the sub tank. When the amount of liquid is less than the predicted liquid amount until the regular maintenance process, the difference between the predicted liquid amount and the remaining liquid amount is set as the liquid shortage amount, and the carriage movement amount for supplying the sub tank with the liquid shortage amount is set. Thus, the interruption of the printing process due to the liquid supply operation until the maintenance process can be suppressed as much as possible. Thereby, the liquid can be replenished satisfactorily while ensuring a good throughput.

In the method for controlling a liquid supply apparatus of the present invention, in the setting step, when the remaining amount of liquid in the main tank is less than a predetermined value, the long time mode of the liquid supply operation and the speed of the liquid supply operation are performed. It is preferable to set at least one of the slow and slow modes.
According to the control method of the liquid supply apparatus, when the remaining amount of liquid in the main tank becomes less than a predetermined value and the negative pressure of the main tank becomes large, the long time mode of the liquid supply operation and the speed of the liquid supply operation are increased. Since at least one of the slow and low speed modes is set, the liquid can be reliably replenished from the main tank in a state where the liquid remaining amount is small to the sub tank. In addition, the time for the liquid replenishment operation when the remaining amount of liquid in the main tank is equal to or greater than a predetermined value can be shortened, and the speed of the liquid replenishment operation can be increased.
That is, it is possible to reliably supply the liquid to the sub tank while greatly increasing the efficiency of the throughput, and it is possible to reduce the size and the cost with a simple structure.

Hereinafter, examples of embodiments of a liquid supply apparatus, a printing apparatus, and a control method for a liquid supply apparatus according to the present invention will be described with reference to the drawings.
1 to 9 are views for explaining an ink jet printer in which an ink supply mechanism is configured by the liquid supply device according to the first embodiment of the present invention. FIG. 1 is an external perspective view of the ink jet printer, and FIG. FIG. 3 is a perspective view of the ink jet printer with the printer cover opened, FIG. 3 is a perspective view of the ink jet printer with the printer case removed, FIG. 4 is a plan view of the ink pump unit and the regulating plate, and FIG. FIG. 6 is a sectional view showing the structure of the self-sealing unit, FIG. 7 is a block diagram for explaining the control system of the ink jet printer, and FIG. 8 is for explaining the ink replenishment operation control by the controller. FIG. 9 is a graph showing the relationship between the carriage position and the ink supply amount.

First, the structure of an inkjet printer that is a printing apparatus according to the present embodiment will be described.
As shown in FIG. 1, an ink jet printer 1 uses a plurality of types of color inks to perform color printing on a part of roll paper that has been fed out. A paper cover 5 and an ink cartridge cover 7 are provided to be freely opened and closed. Further, on the front surface of the printer case 2, a power switch 3 and a feed switch, an indicator, and the like are also arranged.

When the roll paper cover 5 is opened, as shown in FIG. 2, the paper storage unit 13 that stores the roll paper 11 that is a medium to be printed is opened, and the roll paper 11 can be replaced.
When the ink cartridge cover 7 is opened, the cartridge mounting portion 15 is opened, and the ink cartridge (main tank) 17 can be attached to and detached from the cartridge mounting portion 15.

  In this case, the ink cartridge 17 is pulled out by a predetermined distance in front of the cartridge mounting portion 15 in conjunction with the operation of opening the ink cartridge cover 7.

  As shown in FIG. 3, a carriage 23 on which an inkjet head (head) 21 is mounted is provided above the paper storage unit 13 in the printer case 2. The carriage 23 is supported by a guide member 25 extending along the width direction of the roll paper 11 so as to be movable in the paper width direction, and includes an endless belt 26 a and an endless belt 26 a extending in the width direction of the roll paper 11. The carriage motor 26 b that is driven can reciprocate above the platen 28 in the width direction of the roll paper 11. The inkjet head 21 performs a printing process by discharging ink to a part of the roll paper 11 that has been fed.

  As shown in the drawing, the upper portion of the cartridge mounting portion 15 is a standby position (home position) of the carriage 23 that reciprocates. Below this standby position, a cap 27 that covers the ink nozzles of the inkjet head 21 exposed on the lower surface of the carriage 23, and an ink suction that sucks and discards the ink in each ink nozzle of the inkjet head 21 via the cap 27. A mechanism 29 is provided.

In the ink jet printer 1, at a predetermined timing or at the time of user operation, the cap 27 is brought into close contact with the ink nozzle surface of the ink jet head 21, and the inside is sucked by the ink suction mechanism 29 to increase the viscosity of ink and bubbles from the ink nozzle. A cleaning process is performed to suck the air.
Further, in order to form an ink meniscus at the ink nozzles of the inkjet head 21, a flushing process is performed in which a predetermined amount of ink droplets are ejected from the ink nozzles of the inkjet head 21 into the cap 27 before or after the printing process.

  Further, in the inkjet printer 1, capping is performed to protect the cap 27 by closely contacting the ink nozzle surface of the inkjet head 21 disposed at the home position after printing is stopped, and to prevent clogging of the ink nozzle.

  The ink cartridge 17 is a cartridge case 18 in which a plurality of unillustrated color ink packs are accommodated. Each ink pack (storage part) in the ink cartridge 17 is made of a flexible material and has a variable capacity and is sealed in a state where ink is stored inside. The ink cartridge 17 is attached to the cartridge attachment part 15. At this time, an ink supply needle (not shown) provided on the cartridge mounting portion 15 side is inserted and connected to the ink supply port of the ink pack. An ink flow path 31 fixed in the printer case 2 is connected to the ink supply needle of the cartridge mounting portion 15, and one end of a flexible ink supply tube 33 divided into each color is connected to the ink flow path 31. Is connected.

  The other end of the ink supply tube 33 is connected to an ink pump section (replenishment mechanism) 34 for each color provided on the carriage 23. Each ink pump unit 34 is provided above the inkjet head 21 and is connected to a self-sealing unit 36 connected to the inkjet head 21.

In addition to the inkjet head 21, an ink pump unit 34 and a self-sealing unit 36 are integrally mounted on the carriage 23.
As a result, the ink in each ink pack in the ink cartridge 17 passes from the ink supply needle of the cartridge mounting unit 15 to the ink flow path 31, the ink supply tube 33, the ink pump unit 34 for each color, and the self-sealing unit 36 for each color. Then, the ink is supplied to each ink nozzle of the inkjet head 21.

The ink pump unit 34 draws ink from the ink cartridge 17 when the movable carriage 23 moves with respect to the main body of the printer 1, and the ink pump 17 moves to the main body side of the printer 1 by moving the carriage 23. A regulating plate 37 shown in FIG. 4 for operating the unit 34 is arranged in the forward direction of the carriage 23 to the standby position.
In the ink jet printer 1, the ink cartridge 17, the sub tank 45, the ink jet head 21, the carriage 23, and the ink pump unit 34 constitute an ink supply mechanism (liquid supply mechanism).

Next, the ink pump unit 34 constituting the ink supply mechanism will be described by exemplifying a structure for one color.
As shown in FIG. 5, a check valve 41 is provided at the end of the flow path 31 on the ink cartridge 17 side, and the ink cartridge 17 is interposed between the ink cartridge 17 and the ink pump unit 34 by the check valve 41. Ink flows only from the side to the ink pump 34 side.

  The ink pump unit 34 includes a sub tank 45 that draws ink from the ink cartridge 17 through the ink supply tube 33. The sub-tank 45 includes an upper divided body 46 and a lower divided body 47, and a flexible membrane 49 made of a flexible diaphragm is interposed between the upper divided body 46 and the lower divided body 47. It has an ink chamber (liquid chamber) 50 whose upper portion is covered. The flexible membrane 49 is made of butyl rubber or the like having low moisture permeability and gas permeability.

  The ink chamber 50 communicates with the ink supply tube 33 and communicates with the flow path 42 on the self-sealing unit 36 side, and supplies ink from the ink cartridge 17 and supplies ink to the self-sealing unit 36 side. It is possible. A check valve 43 is provided at the end of the ink flow path 42 on the self-sealing unit 36 side, and the ink chamber 50 is interposed between the ink chamber 50 and the self-sealing unit 36 side by the check valve 43. Ink flows only from the side to the self-sealing unit 36 side. The flexible film 49 is made of a flexible material that can be easily deformed. With the deformation of the flexible film 49, the capacity of the ink chamber 50 becomes variable, and is expanded and contracted. The ink pump unit 34 is provided with an expansion mechanism 52 that expands the ink chamber 50 by displacing the flexible film 49.

  The expansion mechanism 52 includes a cylindrical cylinder 53 that extends in the vertical direction, a piston (movable member) 54 that is slidably inserted in the cylinder 53, and a cylinder 53 in the upper divided body 46. A swing arm 56 is swingably supported by the swing shaft 55 disposed, and a tension coil spring (elastic portion) 57 is interposed between the swing arm 56 and the piston 54.

  The cylinder 53 is made of a resin material such as polypropylene having low moisture permeability and gas permeability. The cylinder 53 has an inner diameter slightly larger than the outer diameter of the piston 54, and a small-diameter inner peripheral surface 59 that slidably guides the outer peripheral surface of the piston 54 is formed at the upper portion, and the outer periphery of the piston 54 at the lower portion. A stepped shape is formed in which a large-diameter inner peripheral surface 60 that forms a gap with the surface is formed.

  The piston 54 is made of a resin material such as polypropylene having low moisture permeability and gas permeability. The piston 54 is formed in a substantially bottomed cylindrical shape, and its swing arm 56 side is notched from the upper end to an intermediate position in order to place the swing arm 56.

  A locking portion 67 that locks the lower end of the tension coil spring 57 is formed above the bottom of the piston 54.

  The swing arm 56 includes an arm portion 69 that extends from the swing shaft 55 into the cylinder 53, a vertical extension portion 70 that extends downward from the swing shaft 55, and an arm portion 69 of the vertical extension portion 70. Has an input portion 71 extending from the opposite end portion in the direction opposite to the arm portion 69. The tip of the arm 69 has a bowl shape, and the upper end of the tension coil spring 57 is locked to this portion.

  The flexible film 49 includes an annular thick base portion 74 sandwiched between the upper divided body 46 and the lower divided body 47 in a state of being fitted in the annular groove 73 of the upper divided body 46, and the base portion. The thin film part 75 which extends from the inner peripheral part of the cylinder 74 in a cylindrical shape and the thick substantially disk-shaped fixing part 76 which closes the opposite side of the film part 75 from the base part 74. It is a molded product.

  A tapered projection 77 is integrally formed at the center of the fixed portion 76, and the projection 77 is press-fitted into and fitted into a slit 65 formed in the piston 54. In this state, the fixing portion 76 is integrated with the bottom portion of the piston 54, so that the fixing portion 76 and the membrane portion 75 of the flexible film 49 are displaced by the movement of the piston 54.

  As shown in FIG. 6, in the self-sealing unit 36, a supply path 82, an intermediate path 83, and a discharge path 84 are formed in the unit main body 81. The downstream end of the flow path 42 is connected to the supply port 82 a formed in the supply path 82, and the inkjet head 21 is connected to the discharge port 84 a formed in the discharge path 84.

  An inflow port 85 a is formed in the wall portion 85 that divides the supply path 82 and the intermediate path 83, and the ink in the supply path 82 flows into the intermediate path 83 through the inflow port 85 a. Further, a communication port 86 a is formed in the wall portion 86 that divides the intermediate path 83 and the discharge path 84, and ink in the intermediate path 83 flows into the discharge path 84 through the communication port 86 a.

  A fulcrum portion 87 is formed on the wall portion 86 in the intermediate path 83, and a swing bar 91 is swingably supported on the fulcrum portion 87. The swing rod 91 is integrally formed with an operating rod portion 92 that is bent toward the wall portion 85 at one end thereof, and the tip of the operating rod portion 92 abuts against the wall portion 85. A closing plate 93 for closing the inlet 85a is formed. A compression spring 94 is provided between the closing plate 93 and the wall portion 86, and the closing plate 93 is biased toward the wall portion 85 by the biasing force of the compression spring 94. Further, the other end portion of the swinging rod 91 is formed with a pressing rod portion 95 that is bent toward the wall portion 86 and is inserted into the communication port 86 a of the wall portion 86.

  An opening 96 is formed in the side wall 81a of the unit body 81 on the discharge path 84 side. A liquid-tight and flexible film 97 is liquid-tightly connected to the opening edge portion of the opening 96. A pressing plate 98 is fixed to the central portion of the film 97 on the discharge path 84 side. The tip of the pressing rod portion 95 of the swinging rod 91 is in contact with the pressing plate 98.

  A compression spring 99 is attached between the pressing plate 98 and the wall portion 86, and the pressing plate 98 is pushed outward by the urging force of the compression spring 99. In the self-sealing unit 36, the closing plate 93 is pressed against the wall 85 by the pressure acting on the compression spring 94 and the closing plate 93, and the inflow port 85a is closed.

  In the self-sealing unit 36, when the pressing bar portion 95 of the swinging rod 91 is pressed by the pressing plate 98 as the volume of the portion covered with the film 97 decreases, the swinging rod 91 is moved by the fulcrum portion 87. The closing plate 93 is separated from the wall portion 85 by swinging around the connecting portion. As a result, ink flows from the supply path 82 through the inlet 85 a to the intermediate path 83 and the discharge path 84 and is supplied to the inkjet head 21.

By providing the self-sealing unit 36 on the upstream side of the inkjet head 21, even if ink pressure fluctuation occurs on the supply side due to acceleration / deceleration of the carriage 23, for example, the pressure fluctuation is applied to the inkjet head 21. Is blocked by the self-sealing unit 36.
This prevents problems such as unintentional ink ejection from the inkjet head 21 due to transmission of pressure fluctuations, ink dripping, or missing dots due to defective ejection.

  In the printer 1 having the above structure, when the carriage 23 is in the standby position, the input portion 71 of the swing arm 56 contacts the restriction plate 37 outside the carriage 23, and the vertically extending portion 70 extends vertically along the arm portion 69 and the input. The unit 71 is in a horizontal state. At this time, the piston 54 is pulled up by the biasing force of the tension coil spring 57.

  Further, the carriage 23 moves away from the standby position to position the ink jet head 21 in the printable area, and then the ink jet head 21 discharges ink in the printable area to perform printing, so that the self-sealing unit 36 When ink is supplied to the inkjet head 21 and the pressure in the self-sealing unit 36 becomes negative, ink is supplied from the ink chamber 50 to the self-sealing unit 36 via the flow path 42.

  Here, when the ink in the ink chamber 50 is decreased, the piston 54 is lowered integrally with the fixed portion 76 while the film portion 75 of the flexible film 49 is deformed by the negative pressure generated by the decrease in the ink. Then, the swing arm 56 connected to the piston 54 via the tension coil spring 57 swings so as to lower the tip of the arm portion 69, and as a result, the side of the input portion 71 of the swing arm 56 is moved. The amount of protrusion is increased.

  When the carriage 23 returns to the standby position from this state, the swing arm 56 that moves together with the carriage 23 comes into contact with the regulation plate 37 outside the carriage 23 at the input portion 71, and swings when the carriage 23 moves, and moves up and down. The extending part 70 extends vertically, and the arm part 69 and the input part 71 are horizontal. As a result, the distal end portion of the arm portion 69 rises, and the piston 54 connected via the tension coil spring 57 slides up in the cylinder 53 and is pulled up.

  Due to the movement of the piston 54 performed through the tension coil spring 57, the fixing portion 76 of the flexible film 49 of the ink pump portion 34 rises integrally with the piston 54, and the ink chamber 50 of the sub tank 45 is expanded to increase the capacity. Is done. Thus, when the capacity of the ink chamber 50 increases, the ink is transferred from the ink cartridge 17 through the ink flow path 31 and the ink supply tube 33 while the check valve 41 is opened and the check valve 43 is closed. 50 will be aspirated.

  And in the inkjet printer 1 of the said structure, the control part 100 performs said ink replenishment operation | movement at a predetermined timing. This ink replenishment operation is performed in a state where at least an amount of ink that can supply ink to the inkjet head 21 remains in the ink chamber 50 even when printing that consumes ink to the maximum is performed.

  As shown in FIG. 7, the control unit 100 of the ink jet printer 1 controls the driving of the ink jet head 21 and the carriage motor 26 b by transmitting control signals to the ink jet head 21 and the carriage motor 26 b, and supplies the roll paper 11 to the roll paper 11. A print process or the like is executed. The control unit 100 is connected to an encoder 103 that transmits position information of the carriage 23, and the control unit 100 detects the position of the carriage 23 based on a signal from the encoder 103.

  The control unit 100 includes a detection unit 111, a calculation unit (calculation unit) 112, a comparison unit (determination unit) 113, a storage unit 114, and a CPU (setting unit) 115. The detection unit 111, the calculation unit 112, and the comparison unit 113 are included. Is controlled by the CPU 115.

  A reader / writer 101 is connected to the control unit 100. The reader / writer 101 reads / writes ink information from / to an IC chip (storage means) 102 provided in the ink cartridge 17. The ink information written in the IC chip 102 includes, for example, ink consumption, remaining ink amount, waste ink amount, use start date, and use device information.

  The control unit 100 reads the ink information stored in the IC chip 102 of the ink cartridge 17 mounted on the cartridge mounting unit 15 by the reader / writer 101. If the mounted ink cartridge 17 is new, the use start date and the used device information are written in the IC chip 102.

  When the printing process or the cleaning process is performed, the calculation unit 112 obtains the dot count value of the ink droplets ejected from the ink jet head 21 by the printing process, the flushing process, or the cleaning process, and stores the dot count value in the IC chip 102 as the dot count value. The obtained dot count value is added to the already stored ink consumption amount to update the total ink consumption amount and write it to the IC chip 102.

In the inkjet printer 1, when print data is transmitted, print processing is performed based on the print data.
Specifically, the carriage 23 moves from the standby position to the printing area, and performs printing by ejecting ink droplets from the ink nozzles of the inkjet head 21 based on the print data to the roll paper 11.

In this printing process, when the ink in the sub tank 45 of the ink pump unit 34 runs out, an ink supply operation is performed.
Specifically, when the carriage 23 moves to the standby position, the swing arm 56 that moves together with the carriage 23 swings in contact with the regulation plate 37 outside the carriage 23 at the input unit 71, thereby The tip of 69 is raised, and the piston 54 connected via the tension coil spring 57 slides in the cylinder 53 and is pulled up.

  Due to the movement of the piston 54 performed through the tension coil spring 57, the fixing portion 76 of the flexible film 49 of the ink pump portion 34 rises integrally with the piston 54, and the ink chamber 50 of the sub tank 45 is expanded to increase the capacity. Is done. Thus, when the capacity of the ink chamber 50 increases, the ink is transferred from the ink cartridge 17 through the ink flow path 31 and the ink supply tube 33 while the check valve 41 is opened and the check valve 43 is closed. 50 will be aspirated.

  Further, the inkjet printer 1 performs periodic flushing, which is a maintenance process for forming the ink meniscus of the ink nozzles, every predetermined time during the printing process. When performing regular flushing, the carriage 23 moves to the standby position, and in this state, ink droplets are ejected from the ink nozzles of the inkjet head 21 to the cap 27.

In the ink replenishment operation described above, the ink chamber 50 is expanded and ink is drawn from the ink cartridge 17, so that it takes a considerable time to draw ink to fill the ink chamber 50.
Therefore, if the ink in the sub tank 45 is consumed during the printing process and the ink needs to be replenished, the printing process must be interrupted for a while, which affects the throughput.

For this reason, the control unit 100 controls the ink supply operation according to the printing state.
Next, ink replenishment operation control by the control unit 100 will be described with reference to a flowchart shown in FIG.

  When the printing process is started in the continuous printing, in the control unit 100, the calculation unit 112 adds the printing consumption amount of the ink consumed in the printing and the flushing consumption amount consumed in the flushing, thereby the inkjet head 21. The amount of ink consumed from the ink is calculated (step S01).

Then, the calculating means 112 calculates the ink remaining amount in the subtank 45 at the present time by subtracting the calculated ink consumption from the initial ink amount in the subtank 45 (calculating step: step S02).
Further, the calculation means 112 calculates a predicted ink amount (predicted liquid amount) consumed in the remaining printing based on the remaining print data (print waiting number) (calculation step: step S03).

Next, the comparison unit 113 compares the calculated ink remaining amount in the sub-tank 45 with the predicted ink amount waiting for printing (determination step: step S04).
As a result of the comparison, when the ink remaining amount in the sub tank 45 is larger than the predicted ink amount (step S04: Yes), the CPU 115 continues the printing process based on the remaining print data (step S05).

As a result of the comparison between the remaining ink amount in the sub tank 45 and the predicted ink amount, if the remaining ink amount in the sub tank 45 is less than the predicted ink amount (step S04: No), the calculation unit 112 performs the next regular flushing. Is measured (step S06), and a predicted ink amount (predicted liquid amount) consumed in printing performed until the next regular flushing is calculated (calculation step).
Then, the comparison unit 113 compares the remaining ink amount in the sub tank 45 with the predicted ink amount consumed within the time until the next regular flushing (determination step: step S07).

  As a result of this comparison, when the remaining amount of ink in the sub tank 45 is larger than the predicted ink amount consumed within the time until the next regular flushing (step S07: Yes), the CPU 115 continues printing until the regular flushing. (Step S08).

Thereafter, at the timing of the regular flushing, the carriage 23 moves to the standby position, whereby the ink supply operation into the sub tank 45 is performed (step S09).
At this time, as the carriage 23 moves to the standby position, the swing arm 56 that moves together with the carriage 23 swings in contact with the regulating plate 37 outside the carriage 23 at the input unit 71. As a result, the distal end portion of the arm portion 69 rises, and the piston 54 connected via the tension coil spring 57 slides up in the cylinder 53 and is pulled up.

  Due to the movement of the piston 54 performed through the tension coil spring 57, the fixing portion 76 of the flexible film 49 of the ink pump portion 34 rises integrally with the piston 54, and the ink chamber 50 of the sub tank 45 is expanded to increase the capacity. Is done. Thus, when the capacity of the ink chamber 50 increases, the ink is transferred from the ink cartridge 17 through the ink flow path 31 and the ink supply tube 33 while the check valve 41 is opened and the check valve 43 is closed. 50 will be aspirated.

Then, the CPU 115 performs a flushing process for ejecting ink droplets from the ink nozzles of the inkjet head 21 into the cap 27 with the carriage 23 moved to the standby position (step S10).
Thereafter, the CPU 115 continues the printing process based on the remaining print data (step S11).

  As a result of comparing the ink remaining amount in the sub tank 45 with the predicted ink amount consumed within the time until the next periodic flushing, the ink remaining amount in the sub tank 45 is predicted consumed within the time until the next periodic flushing. When the amount is less than the ink amount (step S07: No), the calculation unit 112 calculates an ink shortage amount (liquid shortage amount) that is insufficient to perform the remaining print processing based on the remaining print data. Further, the CPU 115 retrieves data on the relationship between the position of the carriage 23 and the ink replenishment amount stored as a map in the storage means 114, and determines the position of the carriage 23 for replenishing the sub tank 45 based on the ink shortage amount. (Setting process: Step S12).

  FIG. 9 is a graph showing the relationship between the position of the carriage 23 used in the CPU 115 and the ink supply amount. In this graph, the standby position is the origin 0, and the amount of ink supplied to the sub tank 45 decreases as the carriage 23 moves away from the standby position of the origin 0 toward the printing area. That is, the ink replenishment amount to the sub tank 45 gradually increases from time A when the carriage 23 moves toward the standby position and the swing arm 56 that moves together with the carriage 23 contacts the restriction plate 37. Is set to the maximum replenishment amount B in the state where it is arranged at the standby position of the origin 0.

Then, the CPU 115 moves the carriage 23 toward the standby position, which is the home position, to the determined position of the carriage 23, and performs an ink supply operation into the sub tank 45 (step S13).
At this time, as the carriage 23 moves toward the standby position, the swing arm 56 that moves together with the carriage 23 swings in contact with the regulation plate 37 outside the carriage 23 at the input unit 71. As a result, the distal end portion of the arm portion 69 rises, and the piston 54 connected via the tension coil spring 57 slides up in the cylinder 53 and is pulled up.

Due to the movement of the piston 54 performed through the tension coil spring 57, the fixing portion 76 of the flexible film 49 of the ink pump portion 34 rises integrally with the piston 54, and the ink chamber 50 of the sub tank 45 is expanded to increase the capacity. Is done. Thus, when the capacity of the ink chamber 50 increases, the ink is transferred from the ink cartridge 17 through the ink flow path 31 and the ink supply tube 33 while the check valve 41 is opened and the check valve 43 is closed. 50 will be aspirated.
As a result, the sub tank 45 is replenished with an ink shortage amount necessary for the remaining printing.

  Thereafter, the CPU 115 moves the carriage 23 moved toward the standby position toward the printing area without stopping, and continues the printing process based on the remaining print data (steps S14 and S15).

  According to the embodiment described above, the ink remaining amount in the sub tank 45 and the predicted ink amount ejected from the inkjet head 21 based on the print data are calculated, and the ink remaining amount in the sub tank 45 is less than the predicted ink amount. In this case, the difference between the predicted ink amount and the remaining ink amount is set as the ink shortage amount, and the movement amount of the carriage 23 is set in order to supply the ink shortage amount to the sub tank 45. Interruption can be minimized. Thereby, ink can be replenished satisfactorily while ensuring good throughput.

Further, since the ink discharge amount discharged from the inkjet head 21 before the regular flushing accompanied by the ink refilling operation to the sub tank 45 is calculated as the predicted ink amount, the interruption of the printing process due to the ink refilling operation until the regular flushing is suppressed as much as possible. Can do.
Therefore, the subtank 45 can be reliably replenished with high efficiency while greatly increasing the throughput efficiency, and printing can be performed efficiently, and a simple structure can be reduced in size and cost.

  In addition, a separate drive source for the ink replenishing pump means is not required, and the flow path is not connected at the time of ink replenishment. Therefore, a simple structure can be reduced in size and cost. Also, the reliability can be improved.

  In the above embodiment, the ink shortage is replenished when the ink remaining amount in the subtank 45 is less than the predicted ink amount calculated based on the remaining print data until the regular flushing accompanied by the ink replenishment operation to the subtank 45. However, when the regular flushing is not performed, the ink shortage amount may be replenished when the ink remaining amount in the sub tank 45 is less than the predicted ink amount calculated based on the remaining print data.

By the way, as shown in FIG. 10, the pressure in the ink cartridge 17 gradually decreases as the remaining amount of ink decreases, and rapidly decreases when the ink reaches the near-end region X near the sky.
Therefore, when the ink remaining amount of the ink cartridge 17 is in the near-end region X and the carriage 23 is moved to the standby position and the ink supply operation from the ink cartridge 17 is performed, the swing arm 56 of the sub tank 45 of the ink pump portion 34. Is brought into contact with the regulating plate 37 and the time taken to draw ink into the ink chamber 50 becomes longer, and the load also becomes larger.
If the ink replenishment operation time is set based on the near-end region X having a small amount of ink, the ink replenishment operation time takes more than necessary when the ink remaining in the ink cartridge 17 is sufficient, which affects the throughput. .

For this reason, in addition to the ink replenishment operation control according to the printing state described above, the ink replenishment operation control according to the relationship between the remaining amount of ink in the ink cartridge 17 and the negative pressure may be performed.
That is, after determining the position of the carriage 23 for replenishing the sub-tank 45 with the ink shortage amount in step S12, the ink replenishment operation is changed according to the relationship between the remaining amount of ink in the ink cartridge 17 and the negative pressure.

Specifically, first, the computing unit 112 obtains the remaining amount of ink in the ink cartridge 17 based on the ink information of the IC chip 102 and the amount of ink consumed by the printing process and flushing. Then, as shown in FIG. 11, the comparison unit 113 determines whether or not the remaining amount of ink is less than a predetermined value (step S21).
This predetermined value is the ink remaining amount value that becomes the near-end region X in the relationship between the ink remaining amount and the negative pressure, and is stored in the IC chip 102 of the ink cartridge 17.

As a result, when the ink remaining amount is less than the predetermined value (step S21: Yes), the CPU 115 sets the ink replenishment operation time to the long time mode (step S22).
Here, the ink replenishment operation time in the long-time mode is the state in which the negative pressure in the near end region X in the relationship between the ink remaining amount in the ink cartridge 17 and the negative pressure is the largest, into the ink chamber 50 of the ink pump unit 34. This is the time required to draw ink, and that time is set as T.

On the other hand, when the ink remaining amount is equal to or greater than the predetermined value (step S21: No), the CPU 115 sets the ink supply operation time to the short time mode (step S23).
Here, the ink replenishment operation time in the short time mode is a state in which the ink remaining outside the near-end region X in the relationship between the ink remaining amount in the ink cartridge 17 and the negative pressure is sufficient and the ink chamber 50 in the ink pump unit 34 This is a time required to draw ink into the ink and is set as a time T-α shorter than the ink replenishment operation time T in the long-time mode by the correction time α.

  When either the long-time mode or the short-time mode is set, the CPU 115 moves the carriage 23 toward the standby position, which is the home position, to the position of the carriage 23 determined by the calculation unit 112, and sets the replenished ink. Ink is supplied to the sub tank 45 during the operation time (step S13).

  In this case, when the ink remaining amount of the ink cartridge 17 becomes less than the predetermined value and the negative pressure of the ink cartridge 17 becomes large, the ink replenishment operation time is long and the long time mode is set. Ink can be reliably supplied from the cartridge 17 to the sub tank 45. In addition, it is possible to shorten the time for the ink supply operation when the ink remaining amount in the ink cartridge 17 is equal to or greater than the predetermined value.

  That is, it is possible to perform printing efficiently by reliably supplying ink to the sub tank 45 while greatly increasing the efficiency of the throughput. In addition, it is possible to reduce the size and cost with a simple structure.

  In the above example, the ink replenishment operation time during the ink replenishment operation is changed according to the ink remaining amount of the ink cartridge 17, but the ink replenishment including the moving speed of the carriage 23 according to the ink remaining amount of the ink cartridge 17 is performed. The operation speed may be changed.

As shown in FIG. 12, the comparison unit 113 compares the remaining ink amount with a predetermined value, and if the remaining ink amount is less than the predetermined value (step S31: Yes), the CPU 115 sets the ink supply operation speed to the low speed mode. (Step S32).
Here, the ink replenishment operation speed in the low-speed mode is such that ink enters the ink chamber 50 of the ink pump unit 34 in a state where the negative pressure is the largest in the near-end region X in the relationship between the ink remaining amount in the ink cartridge 17 and the negative pressure. This speed is necessary for pulling in, and the speed is set as V.

On the other hand, when the ink remaining amount is not less than the predetermined value (step S31: No), the CPU 115 sets the ink supply operation speed to the high speed mode (step S33).
Here, the ink replenishment operation speed in the high speed mode is such that the ink remaining outside the near-end region X in the relationship between the ink remaining amount and the negative pressure in the ink cartridge 17 is sufficient to enter the ink chamber 50 of the ink pump unit 34. This is a speed necessary for drawing ink, and is set as a speed V + β that is faster than the ink replenishment operation speed V in the low speed mode by a correction speed β.

  When set to either the low speed mode or the high speed mode, the CPU 115 moves the carriage 23 toward the standby position, which is the home position, to the position of the carriage 23 determined by the calculation means 112, and sets the ink replenishment operation speed. Then, the ink supply operation to the sub tank 45 is performed (step S13).

  In this way, when the ink remaining amount of the ink cartridge 17 becomes less than the predetermined value and the negative pressure of the ink cartridge 17 becomes large, the ink replenishment operation speed is set to the low speed mode. Ink can be reliably supplied from 17 to the sub tank 45. In addition, it is possible to increase the speed of the ink supply operation when the ink remaining amount of the ink cartridge 17 is equal to or greater than a predetermined value.

  That is, it is possible to perform printing efficiently by reliably supplying ink to the sub tank 45 while greatly increasing the efficiency of the throughput. In addition, it is possible to reduce the size and cost with a simple structure.

  In the above example, the ink supply operation time or the ink supply operation speed is changed according to the ink remaining amount of the ink cartridge 17, but both the ink supply operation time and the ink supply operation speed may be changed.

For example, in the comparison determination process between the ink remaining amount and a predetermined value, when the ink remaining amount is less than the predetermined value, the ink replenishing operation time may be increased and the ink replenishing operation speed may be decreased.
As described above, when the ink remaining amount of the ink cartridge 17 becomes less than the predetermined value and the negative pressure of the ink cartridge 17 becomes large, the ink replenishing operation time is lengthened, and the ink replenishing operation speed is slowed to reduce the ink remaining amount. The liquid can be more reliably replenished from the ink cartridge 17 in a small amount to the sub tank 45.

  In the above embodiment, the ink shortage amount is supplied to the sub tank 45. However, it is sufficient to supply at least the ink shortage amount. Therefore, in this embodiment, since the tension coil spring 57 is interposed between the swing arm 56 and the piston 54, the amount of replenishment varies depending on the carriage speed and the like. Supply more than the amount. If the replenishment amount can be adjusted accurately, only the deficient amount needs to be replenished. In this case, the throughput is further improved.

The liquid supply apparatus according to the present invention includes a color material discharge head, an organic EL display, and an FED (surface emitting display) used for manufacturing a color filter such as a liquid crystal display, including the ink jet printer exemplified in the above embodiment. ) Electrode material discharge head used for electrode formation, bioorganic discharge head used for biochip manufacturing, etc., liquid supply device for supplying liquid to the liquid discharge head, and sample discharge device as a precision pipette It can also be applied to a liquid supply device or the like.
Further, the concept of liquid includes gel-like, highly viscous, and solid mixed with a solvent, and the concept of ink includes water-based ink and oil-based ink.

1 is an external perspective view showing an ink jet printer that is an example of a printing apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view of a state in which a printer cover of the ink jet printer of FIG. 1 is opened. FIG. 2 is a perspective view of a state where a printer case is removed from the ink jet printer of FIG. 1. FIG. 2 is a plan view showing an ink pump part and a regulating plate of the ink jet printer of FIG. 1. It is sectional drawing which shows the principal part of the ink supply mechanism of the inkjet printer of FIG. It is sectional drawing which shows the structure of the self-sealing unit of the inkjet printer of FIG. FIG. 2 is a block diagram illustrating a control system of the ink jet printer of FIG. 1. 2 is a flowchart illustrating ink replenishment operation control by a control unit of the ink jet printer of FIG. 1. 2 is a graph showing a relationship between a carriage position and an ink supply amount in the ink jet printer of FIG. 1. 2 is a graph showing the relationship between the remaining amount of ink in an ink cartridge and the internal pressure in the ink jet printer of FIG. 1. 3 is a flowchart showing control for changing an ink replenishment operation time in the ink jet printer of FIG. 1. 2 is a flowchart illustrating control for changing an ink replenishment operation speed in the ink jet printer of FIG. 1.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Inkjet printer (printing apparatus, liquid supply apparatus), 17 ... Ink cartridge (main tank), 21 ... Inkjet head (head), 23 ... Carriage, 34 ... Ink pump part (replenishment mechanism), 45 ... Sub tank, 112 ... Calculation means 113... Comparison means (determination section), 115... CPU (setting section).

Claims (7)

A main tank in which liquid is stored in a sealed variable capacity storage section;
A sub tank in which liquid is replenished from the main tank;
A head capable of discharging liquid supplied from the sub tank;
A carriage on which the head and the sub tank are mounted and movable;
A liquid supply device having a replenishment mechanism for replenishing liquid supplied to the head from the main tank to the sub tank by movement of the carriage,
A calculation unit that calculates a remaining liquid amount in the sub tank and a predicted liquid amount to be discharged from the head based on a discharge command;
A determination unit that determines whether the liquid remaining amount in the sub tank is less than the predicted liquid amount;
When the remaining liquid amount in the sub-tank is less than the predicted liquid amount, the difference between the predicted liquid amount and the remaining liquid amount is set as a liquid shortage amount, and the liquid shortage amount is replenished to the sub tank. A liquid supply apparatus comprising: a setting unit that sets a movement amount of the carriage. The liquid supply device according to claim 1,
The liquid supply device, wherein the calculation unit calculates a liquid discharge amount discharged from the head as the predicted liquid amount before a periodic maintenance process involving a liquid replenishment operation to the sub tank. The liquid supply apparatus according to claim 1 or 2,
When the remaining amount of liquid in the main tank is less than a predetermined value, the setting unit sets at least one of a long-time mode in which the liquid supply operation is long and a low-speed mode in which the liquid supply operation is slow. The liquid supply apparatus characterized by the above-mentioned. A printing apparatus that performs a printing process by discharging ink from the head to a conveyed medium,
A printing apparatus comprising the liquid supply apparatus according to claim 1 as an apparatus for supplying ink to the head. A main tank in which liquid is stored in a sealed variable capacity storage section, a sub tank in which liquid is supplied from the main tank, a head capable of discharging liquid supplied from the sub tank, the head and the sub tank A liquid supply device having a movable carriage and a replenishment mechanism for replenishing the liquid supplied to the head from the main tank to the sub-tank by movement of the carriage,
A calculation step of calculating a remaining amount of liquid in the sub tank and a predicted liquid amount to be discharged from the head based on a discharge command;
A determination step of determining whether or not the remaining liquid amount in the sub-tank is less than the predicted liquid amount;
When the remaining liquid amount in the sub-tank is less than the predicted liquid amount, the difference between the predicted liquid amount and the remaining liquid amount is set as a liquid shortage amount, and the liquid shortage amount is replenished to the sub tank. And a setting step for setting the amount of movement of the carriage. It is a control method of the liquid supply apparatus according to claim 5,
The liquid supply device control method according to claim 1, wherein, in the calculation step, a liquid discharge amount discharged from the head is calculated as the predicted liquid amount before a periodic maintenance process involving a liquid replenishment operation to the sub tank. It is a control method of the liquid supply apparatus according to claim 5 or 6,
In the setting step, when the remaining amount of liquid in the main tank is less than a predetermined value, at least one of a long-time mode in which the liquid replenishment operation is long and a low-speed mode in which the liquid replenishment operation is slow is set. A control method for a liquid supply apparatus.

Images