JP2010221466A - Liquid jetting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide another technique enabling stable delivering (jetting) of liquid. <P>SOLUTION: A liquid jetting apparatus includes: a liquid storing part for storing the liquid; a liquid jetting part for jetting the liquid fed from the liquid storing part; a heating part for heating the liquid; and a controlling part for controlling the heating part. The controlling part controls the heating part based on the flow speed of the liquid fed to the liquid jetting part from the liquid storing part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a liquid ejecting apparatus.

  In the ink jet printer, when high-viscosity ink is used, there is a possibility that ink ejection from the ink head for ejecting ink becomes unstable. In order to solve such a problem, an inkjet including a temperature detection unit that detects the temperature of the ink in the ink tank and a heating unit that heats a supply path that connects the ink tank and the ink head based on the detection result. A printer has been proposed (see, for example, Patent Document 1).

JP 2003-127417 A

  However, as described in Patent Document 1, even if the heating unit is controlled based only on the temperature of the ink in the ink tank, the ink ejection may not be stable.

  Such a problem is not limited to an ink jet printer, and is a problem common to a liquid ejecting apparatus including a liquid ejecting unit that ejects a liquid, such as an apparatus for manufacturing a color filter such as a liquid crystal display.

  Therefore, an object of the present invention is to provide another technique that enables stable discharge (injection) of a liquid.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
A liquid ejecting apparatus,
A liquid reservoir for storing liquid;
A liquid ejecting section that ejects the liquid supplied from the liquid storage section;
A heating unit for heating the liquid;
A control unit for controlling the heating unit;
With
The controller is
A liquid ejecting apparatus that controls the heating unit based on a flow rate of the liquid supplied from the liquid storage unit to the liquid ejecting unit.

  In the present specification, the flow rate is not limited to the liquid flow rate per unit time (for example, 1 ms). For example, the flow rate of liquid per one ejection per one main scan, per page, etc. may be used. The liquid flow rate includes information such as the amount of liquid ejected from the liquid ejecting unit, the amount of liquid supplied to the liquid ejecting unit, and the number of dots.

  When the liquid flow rate is high, the liquid does not warm sufficiently even when heated, as in the case where the flow rate is slow, and the liquid discharge (jetting) may not be stable because the viscosity of the liquid is not low enough. is there. With respect to this problem, according to this liquid ejecting apparatus, since the heating unit is controlled based on the flow rate of the liquid, even when the flow rate of the liquid is high, the reduction in the viscosity of the liquid is improved. The stability of discharge (injection) is improved.

[Application Example 2]
The liquid ejecting apparatus according to Application Example 1,
A temperature-related information acquisition unit that acquires information about the temperature of the liquid;
The controller is
A liquid ejecting apparatus that controls the heating unit based on the flow rate of the liquid and the temperature-related information acquired by the temperature-related information acquisition unit.

  In this case, since the heating of the liquid is controlled based on the temperature of the liquid, the stability of liquid ejection (ejection) is further improved. Note that the temperature-related information may be information such as resistance, voltage, and current related to the temperature of the liquid, or may be information representing the temperature itself.

[Application Example 3]
A liquid ejecting apparatus according to Application Example 2,
A cooling unit for cooling the liquid;
The controller is
A liquid ejecting apparatus that controls the cooling unit based on the temperature-related information.

  If it does in this way, when the temperature of the liquid will rise too much from the target temperature, it can cool. Thereby, for example, the temperature of the liquid can be kept constant.

[Application Example 4]
The liquid ejecting apparatus according to Application Example 1,
The controller is
A liquid ejecting apparatus that controls the liquid ejecting unit based on image data representing an image and derives the flow velocity of the liquid based on the image data.

  In this way, the liquid flow rate can be derived easily.

[Application Example 5]
A liquid ejecting apparatus,
A liquid reservoir for storing liquid;
A liquid ejecting section that ejects the liquid supplied from the liquid storage section;
A heating unit for heating the liquid;
A control unit for controlling the heating unit;
With
The controller is
A liquid ejecting apparatus that controls the liquid ejecting unit based on image data representing an image and controls the heating unit based on the image data.

  Here, “image data” includes data representing photographs, pictures, figures, characters, symbols, and the like. According to this liquid ejecting apparatus, the heating unit is controlled based on the image data. For example, the heating unit can be controlled based on each value of R, G, and B data. Moreover, a heating part can be controlled based on each value of C, M, Y, and K data. In this way, the control circuit can be simplified.

  The present invention is not limited to the above-described aspect of the liquid ejecting apparatus, but includes various methods such as a method for controlling the liquid ejecting apparatus, a computer program for controlling the liquid ejecting apparatus, and a storage medium storing the computer program. Can be realized.

It is a perspective view which shows an example of an inkjet printer. It is explanatory drawing which shows notionally the structure of the principal part of the inkjet printer as 1st Example of this invention. It is a schematic diagram which shows typically the cross-sectional structure of the principal part of a print head. It is a flowchart showing the control routine of the supply path cooling / heating apparatus performed in the control part in a present Example. It is explanatory drawing which shows notionally the structure of the principal part of the inkjet printer as a 2nd Example of this invention. It is a schematic diagram which shows typically the structure of the subtank in a present Example, and arrangement | positioning of a 1st heating apparatus. It is a schematic diagram which shows typically the structure of the printing head and arrangement | positioning of a 3rd heating apparatus in a present Example. It is a flowchart showing the control routine of the heating apparatus performed in the control part in a present Example. It is explanatory drawing which shows notionally the structure of the principal part of the inkjet printer as a 3rd Example of this invention. It is a flowchart showing the control routine of the heating apparatus performed in the control part in a present Example. It is a schematic diagram which shows the structure of an ink cartridge, and arrangement | positioning of a heating apparatus and a temperature detection part.

Hereinafter, the best mode for carrying out the present invention will be described in the following order based on examples.
A. Overall configuration of inkjet printer:
B. First embodiment:
C. Second embodiment:
D. Third embodiment:
E. Variation:

A. Overall configuration of inkjet printer:
FIG. 1 is a perspective view illustrating an example of an inkjet printer. An inkjet printer 1000A shown in FIG. 1A has a carriage 200A that moves in the main scanning direction, and also has a transport mechanism that transports the printing paper PP in the sub-scanning direction. A print head (not shown) is provided at the lower end of the carriage 200, and printing is performed on the print paper PP using this print head.

  An ink cartridge is not mounted on the carriage 200A, and a cartridge storage unit 220 is provided outside the printer body (outside the carriage movement range). An ink supply tube 210 connects between the ink cartridge 100 and the carriage 200A. Thus, a printer in which an ink cartridge is mounted in a place other than the carriage is also called an “off-carriage type printer”.

  An ink jet printer 1000B shown in FIG. 1B has a carriage 200B and a transport mechanism for transporting the printing paper PP in the sub-scanning direction, like the ink jet printer 1000A. However, unlike the ink jet printer 1000A shown in FIG. 1A, a cartridge housing portion in which a plurality of ink cartridges 100 can be mounted is provided on the carriage 200B. As described above, the printer in which the ink cartridge is mounted on the carriage is also referred to as an “on-carriage type printer”.

  In the following description, the case where an off-carriage type ink jet printer is used will be mainly described. However, the contents can be applied to an on-carriage type ink jet printer as well.

B. First embodiment:
B1. Main components of inkjet printer:
FIG. 2 is an explanatory diagram conceptually showing the structure of the main part of the ink jet printer as the first embodiment of the present invention. In FIG. 2, the part related to the ink heating control in this embodiment is illustrated as a main part. The ink jet printer 1100A mainly includes an ink cartridge 100, an ink supply tube 210, a carriage 200A, and a control unit 600. 2 illustrates the ink cartridge 100 for one color (for example, black ink) and the corresponding parts (the sub tank 300, the supply path 400, etc.), but as illustrated in FIG. The printer 1100A includes a plurality of color ink cartridges 100 (for example, cyan, magenta, and yellow), and is provided with an ink supply tube 210, a sub tank 300, a supply path 400, and the like corresponding to each ink cartridge 100.

  The ink cartridge 100 contains liquid ink therein. As shown in FIG. 1A, the ink cartridge 100 is disposed outside the printer main body (outside the movement range of the carriage 200A), and the ink cartridge 100 and the carriage 200A are connected by an ink supply tube 210. ing. The ink inside the ink cartridge 100 is supplied to the carriage 200 </ b> A via the ink supply tube 210.

  The carriage 200 </ b> A includes a sub tank 300, a supply path 400, a print head 500, a supply path cooling / heating device 420 </ b> A, and a head temperature detection unit 514. An ink supply tube 210 is connected to the sub tank 300, and the liquid ink stored in the ink cartridge 100 flows into the sub tank 300 through the ink supply tube 210. Since the sub tank 300 has a function as a pressure damper, ink pressure fluctuations are absorbed. The sub tank 300 is connected to the print head 500 via the supply path 400. Accordingly, the ink is supplied to the print head 500 via the supply path 400 in a state where the pressure fluctuation is absorbed in the sub tank 300. The configuration of the print head 500 will be described later.

  The supply path cooling / heating device 420A includes a Peltier element, and generates and absorbs heat based on a control signal output from a control unit described later. The supply path cooling / heating device 420 </ b> A is provided in contact with the outside of the supply path 400, and heats or cools the ink in the supply path 400 via the supply path 400. The head temperature detection unit 514 includes a temperature sensor, measures the temperature of ink in the print head 500, and outputs a measurement signal to the control unit 600.

  The control unit 600 is configured as a logic circuit centered on a microcomputer. Specifically, a CPU 602 that executes predetermined calculations according to a preset control program, a ROM that stores control programs and control data necessary for executing various calculation processes by the CPU 602, and various types of CPUs 602. A memory 604 including a RAM that temporarily reads and writes various data necessary for arithmetic processing, an input / output port 606 that inputs and outputs various signals, and the like are provided.

  The control unit 600 develops print data transmitted from an external device (for example, a computer) into ejection data corresponding to a dot pattern, and transmits it to the print head 500. Further, the control unit 600 calculates the amount of ink used (consumption) based on the input print data. Specifically, the control unit 600 calculates the amount of ink used by multiplying the number of ink droplets ejected by the print head 500 by the design liquid amount of the ink droplets to be ejected. For example, when the design liquid amount of the ink droplet of a small dot is set to 2 ng, and the number of ejections of the small dot is 1000, the ink is obtained by multiplying the number of ejections by 2 ng which is the design liquid amount. The amount used is 2000 ng.

  The control unit 600 acquires a measurement signal from the head temperature detection unit 514 provided in the print head 500, and outputs a control signal for controlling the supply path cooling / heating device 420A based on the acquired signal. In addition, the control unit 600 outputs control signals for controlling each unit related to printing, such as the carriage 200A, the transport mechanism, and the print head 500 of the inkjet printer 1100A.

  FIG. 3 is a schematic diagram schematically showing a cross-sectional configuration of a main part of the print head 500. A plurality of (for example, 180) nozzle openings 508 are arranged in a line on the lower surface of the print head 500. In this embodiment, for the sake of simplicity, the print head 500 is illustrated as having a plurality of nozzle openings 508 arranged in one row, but is configured to be arranged in a plurality of rows. May be. Further, in FIG. 3, corresponding to FIG. 2, a configuration inside the print head 500 for ejecting one color ink (for example, black ink) as a main part is illustrated, but as described above, The print head 500 has the same configuration for the other color inks.

  The interior of the print head 500 is partitioned into a plurality of spaces. Specifically, it is divided into an in-head flow path 502, a common ink chamber 504, a pressure chamber 506, and an actuator chamber 509. A supply path 400 is connected to the in-head flow path 502, and ink in a state where pressure fluctuation is absorbed in the sub tank 300 flows into the in-head flow path 502 through the supply path 400. The print head 500 is provided with a head temperature detection unit 514 that measures the temperature of the ink in the in-head flow path 502.

  The common ink chamber 504 communicates with the in-head flow path 502 and is a chamber into which ink from the in-head flow path 502 is introduced. A plurality of pressure chambers 506 are formed corresponding to each nozzle opening 508 as a long and narrow chamber in a direction orthogonal to the direction in which the nozzle openings 508 are arranged (nozzle row direction). The ink introduced into the common ink chamber 504 is distributed and supplied to each pressure chamber 506 through the ink supply port 505.

  In the actuator chamber 509, a piezo element 510 as a drive element for ejecting ink droplets is provided. The actuator chamber 509 and the pressure chamber 506 are partitioned by a vibration plate 511, and the piezo element 510 is disposed in contact with the vibration plate 511. When a drive signal corresponding to the print data is supplied from the control unit 600 to the piezo element 510, the piezo element 510 expands and contracts. When the piezo element 510 is expanded, the diaphragm 511 is deformed accordingly. As a result, the volume of the pressure chamber 506 decreases, and the reduced volume of the pressure chamber 506 becomes an ink droplet and is ejected from the nozzle opening 508.

B2. Control routine of supply path cooling section:
FIG. 4 is a flowchart showing a control routine of the supply path cooling / heating device executed in the control unit in the present embodiment. This routine is executed when the power of the ink jet printer 1100A is turned on.

  When a print command is input from the external device (step S102), the control unit 600 calculates an ink ejection amount per page based on the print data input from the external device together with the print command (step S104).

  The controller 600 determines whether or not the ink ejection amount per page calculated in step S104 is larger than a predetermined set amount (step S106). In the present embodiment, an ink amount that does not reach a set temperature (for example, 35 ° C.) even when heated for 3 seconds by a weak heating described later is set as the set amount.

  In step S106, when the ink ejection amount per page is larger than the set amount (YES in step S106), the control unit 600 outputs a drive signal to the supply path cooling / heating device 420A to supply the supply path. The cooling device 420A is heated strongly (step S108). In this embodiment, for example, heating with an amount of heat that raises the temperature of the ink by 10 ° C. by heating for 1 second is referred to as “strong heating”.

  Then, the control unit 600 determines whether the temperature of the ink in the print head 500 is higher than the set temperature based on the measurement signal output from the head temperature detection unit 514 (step S110). When the detected temperature of ink is lower than the set temperature (NO in step S110), control unit 600 continues to cause strong heating of supply path cooling / heating device 420A (step S108). That is, strong heating is continued in the supply path cooling / heating device 420A until the ink detection temperature becomes higher than the set temperature. In step S110, when the detected temperature of ink becomes higher than the set temperature, control unit 600 proceeds to step S116.

  On the other hand, when the ink ejection amount per page is equal to or less than the set amount in step S106 (NO in step S106), control unit 600 outputs a drive signal to supply path cooling / heating device 420A for supply. The road cooling apparatus 420A is weakly heated (step S112). In this embodiment, for example, heating with an amount of heat that raises the temperature of the ink by 10 ° C. by heating for 3 seconds is referred to as “weak heating”.

  Then, the control unit 600 determines whether the temperature of the ink in the print head 500 is higher than the set temperature based on the measurement signal output from the head temperature detection unit 514 (step S114). When the detected temperature of the ink is lower than the set temperature (NO in step S114), control unit 600 continues to weakly heat supply path cooling / heating device 420A (step S112). That is, weak heating is continued in the supply path cooling / heating device 420A until the ink detection temperature becomes higher than the set temperature. In step S114, when the detected temperature of ink becomes higher than the set temperature, control unit 600 proceeds to step S116.

  In step S116, the control unit 600 determines whether the detected temperature of the ink is higher than [set temperature + 5 ° C.]. When the detected temperature of ink is higher than [set temperature + 5 ° C.] (YES in step S116), control unit 600 outputs a drive signal to supply path cooling / heating device 420A to supply path cooling / heating. The apparatus 420A is cooled (step S118). The controller 600 causes the supply path cooling / heating device 420A to cool down until the detected temperature of the ink becomes equal to or lower than the [set temperature + 5 ° C.] (steps S116 and S118).

  In this embodiment, the control unit 600 executes printing by executing a print control routine that controls each unit that executes printing, such as the carriage 200A, the print head 500, and the conveyance mechanism, separately from this routine. When a print command is input from an external device, the control unit 600 determines whether or not the ink detection temperature is higher than the set temperature based on the measurement signal output from the head temperature detection unit 514, and detects the ink detection temperature. When the temperature becomes higher than the set temperature, a control signal is output to each of the above-described units to start printing. When printing for one page is completed, the control unit 600 turns on a print end flag stored in advance in the memory 604. When starting the next printing, the control unit 600 turns off the print flag.

  In step S116 of the supply path cooling / heating unit control routine, when the detected temperature of the ink becomes equal to or lower than [set temperature + 5 ° C.] (NO in step S116), the control unit 600 determines whether printing for one page is completed. (Step S120). Specifically, when the print end flag described in memory 604 is ON (YES in step S120), control unit 600 proceeds to step S122 and determines whether there is next print data. (Step S122).

  On the other hand, when the print end flag described in the memory 604 is OFF (NO in step S120), the control unit 600 returns to step S106 and sets the ink ejection amount per page and the ink detection temperature. Based on this, the supply path cooling / heating device 420A is controlled to perform strong heating (step S108) or weak heating (step S112) and cooling (step S118). That is, until printing for one page is completed, control unit 600 repeatedly executes steps S106 to S120 to maintain the ink temperature at a substantially set temperature.

  If the control unit 600 determines in step S122 that there is next print data (for example, print data for the second page), the process returns to step S104. On the other hand, if there is no next print data, the control unit 600 ends this routine.

B3. Effects of the embodiment:
In an ink jet printer in which ink in an ink cartridge is supplied to a print head and ejected by the print head, the ink stored in the ink cartridge is a high-viscosity ink (for example, having a viscosity that decreases with increasing temperature). Ink of 10 mPa · S or more, UV ink that is cured and fixed by irradiation with UV light (ultraviolet rays), and the like may be used. High-viscosity ink has high viscosity when the temperature of the ink is low, and when the viscosity of the ink is high, for example, pressure loss due to flow path resistance increases in the supply path, and the supply of ink to the print head becomes unstable. Or the ejection (ejection) of ink in the print head may become unstable.

  On the other hand, the ink jet printer 1100A of this embodiment includes a supply path cooling / heating device 420A for heating / cooling the supply path 400, and the supply path 400 is heated by the supply path cooling / heating apparatus 420A to increase the temperature of the ink. As a result, the viscosity of the ink is reduced.

  Further, as described above, the ink jet printer 1100A according to the present embodiment further includes the control unit 600, and the control unit 600 controls the supply path cooling / heating device 420A based on the ink ejection amount per page to perform strong heating. Or, weak heating is performed.

  For example, when printing a page composed only of characters (hereinafter also referred to as “character page”) and a page (hereinafter also referred to as “photo page”) in which a photograph is displayed on one side of one page. Compared to the case, the amount of ink used to print one page is larger for photo pages than for character pages. In other words, the flow rate of ink supplied from the ink cartridge 100 to the print head 500 (the flow rate of ink per unit time) is larger for photo pages than for character pages.

  If both a character page and a photo page are printed, if the heating is performed weakly by the supply path cooling / heating device 420A, when the photo page is printed, the supply path cooling / heating device 420A is distributed. Since the ink flow rate is high, the ink may not be sufficiently heated, and the ink may not be sufficiently reduced in viscosity.

  On the other hand, in the inkjet printer 1100A of the present embodiment, as described above, the control unit 600 uses the heating in the supply path cooling / heating device 420A for strong heating and weak heating based on the ink ejection amount per page. It is divided. For this reason, even when the ink ejection amount per page is larger than the set amount (when the flow velocity is large), the ink heating state is improved and the ink viscosity is improved. As a result, the stability of ink ejection (ejection) in the print head 500 can be improved.

  The ink jet printer 1100A according to the present embodiment further includes a head temperature detection unit 514 that detects the ink temperature in the print head 500. Then, the control unit 600 controls the supply path cooling / heating device 420A based on the measurement signal of the head temperature detection unit 514 to perform strong heating or weak heating during printing. Therefore, the ink temperature can be maintained substantially constant.

C. Second embodiment:
FIG. 5 is an explanatory diagram conceptually showing the structure of the main part of an ink jet printer as a second embodiment of the present invention. The configuration of the inkjet printer 1100B of this embodiment is different from that of the inkjet printer 1100A of the first embodiment in that a third heating device 340 for heating the sub tank 300 and a first heating device 512 for heating the print head 500 are added. The second heating device 420B is provided instead of the supply path cooling / heating device 420A, and the head temperature detection unit 514 is not provided. That is, in the inkjet printer 1100B in the present embodiment, three heating devices are provided. The first heating device 512, the second heating device 420B, and the third heating device 340 in the present embodiment are heated with the same amount of heat as that of “strong heating” in the first embodiment at the time of driving.

  FIG. 6 is a schematic diagram schematically showing the configuration of the sub tank and the arrangement of the first heating device in the present embodiment. 6A shows a non-printing state, and FIG. 6B shows a printing state. As shown in FIG. 6A, the interior of the sub tank 300 is partitioned into a plurality of spaces. Specifically, it is divided into an ink introduction path 321, an ink supply chamber 322, a pressure chamber 323, and an ink outlet path 324. An ink supply tube 210 is connected to the ink introduction path 321, and ink in the ink cartridge 100 flows into the ink introduction path 321 through the ink supply tube 210.

  In the ink supply chamber 322, an opening / closing member 330 that opens and closes a flow path 325 that connects the ink supply chamber 322 and the pressure chamber 323 is provided. The opening / closing member 330 includes a spring portion 332, a lid portion 334, and a seal ring 336. The ink supply chamber 322 forms a cylindrical space. The lid portion 334 has a shape in which a cylinder protrudes from the center of the disk, and the column portion is inserted into the flow path 325. As shown in FIG. 6A, when the print head 500 does not print, that is, in a state where ink is not consumed, the spring portion 332 urges the lid portion 334 to push up toward the pressure chamber 323. ing. At this time, the cover 334 and the seal ring 336 are in contact with each other, so that the flow path 325 is sealed.

  A part of the pressure chamber 323 is constituted by a film member 352. A pressure receiving plate 354 is attached to a substantially central portion of the film member 352. The pressure receiving plate 354 is formed of a material harder than the film member 352. In this embodiment, the film member 352 has a structure in which a nylon film coated with vinylidene chloride (saran) is bonded and laminated to a high-density polyethylene film. The film member 352 may have a configuration other than that of the present embodiment, but is soft so that a negative pressure state can be efficiently sensed, has no chemical influence on the ink properties, and further has a moisture permeation. It is preferable to use a material having a low degree of permeability and oxygen or nitrogen permeability.

  In the present embodiment, the pressure receiving plate 354 is made of a plastic material such as polyethylene or polypropylene. Other materials may be used for the pressure receiving plate 354. The pressure receiving plate 354 does not change the pressure in the pressure chamber 323 by moving the film member 352 by the weight of the pressure receiving plate 354 itself and the acceleration of the carriage 200A when the carriage 200A is moved by a printing operation or the like. Furthermore, it is preferable that it is lightweight.

  The pressure chamber 323 is connected to the ink supply chamber 322 via the flow path 325. As shown in FIG. 6B, when the print head 500 is in a printing state and ink is consumed, the film member 352 is moved to the ink supply chamber 322 side (paper surface as the ink in the pressure chamber 323 decreases). Displace to the lower side. Then, the central portion of the film member 352 contacts the lid portion 334.

  When ink is further consumed in the print head 500, a negative pressure is generated in the pressure chamber 323. When the negative pressure is generated in this manner and a certain condition is satisfied, the film member 352 presses the lid portion 334, and the sealing of the flow path 325 by the lid portion 334 is released. Then, as indicated by an arrow in FIG. 6B, ink in the ink supply chamber 322 is supplied to the pressure chamber 323 through the flow path 325. Note that, during the printing operation, the lid 334 maintains a state in which a slight gap is generated with the seal ring 336 and acts so that ink is sequentially supplied to the pressure chamber 323.

  The pressure chamber 323 is connected to the ink outlet path 324, and the ink in the pressure chamber 323 flows into the supply path 400 via the ink outlet path 324.

  A third heating device 340 is provided on the bottom surface of the sub tank 300 (FIG. 6A). The third heating device 340 includes a general electric heater and generates heat based on a control signal output from the control unit 600. The third heating device 340 is provided in contact with the outside of the sub-tank 300, and in the internal space of the sub-tank 300 (ink introduction path 321, ink supply chamber 322, pressure chamber 323, ink lead-out path 324) via the sub tank 300. Heat the ink.

  FIG. 7 is a schematic diagram schematically showing the configuration of the print head and the arrangement of the third heating device in the present embodiment. Since the configuration of the print head 500 in this embodiment is the same as that of the print head 500 in the first embodiment, the same reference numerals as those in the first embodiment are used, and the description of the configuration of the print head 500 is as follows. Omitted.

  The first heating device 512 is provided on the outside of the wall surface constituting the in-head flow path 502 in the print head 500. Similar to the third heating device 340, the first heating device 512 includes a general electric heater, and generates heat based on a control signal output from the control unit 600. The first heating device 512 heats the ink in the internal space of the print head 500 (the flow path 502 in the head, the common ink chamber 504, the ink supply port 505, and the pressure chamber 506) via the print head 500.

  In addition, with the difference in these configurations, the flow of ink heating control in the control unit 600 is also different. FIG. 8 is a flowchart showing a control routine of the heating device executed in the control unit in the present embodiment. This routine is executed when the power of the inkjet printer 1100B is turned on.

  When a print command is input from the external device (step T102), the controller 600 calculates an ink ejection amount per page based on the print data input from the external device together with the print command (step T104).

  The controller 600 divides the ink ejection amount per page calculated in step T104 into “low”, “medium”, and “high” (step T106). In this embodiment, the case where the ink ejection amount per page is smaller than the ink amount in the print head 500 is “small”, and the ink ejection amount per page is larger than the ink amount in the print head 500 (print head 500+ The case where the ink amount is smaller than the ink amount in the supply path 400) is “medium”, and the case where the ink ejection amount per page is larger than the ink amount in the (print head 500 + supply path 400) is “many”.

  When the ink ejection amount per page is “low” in step T106 (“low” in step T106), the control unit 600 outputs a drive signal to the first heating device 512, and the first 1 The heating device 512 is driven (step T108).

  When the ink ejection amount per page is “medium” in step T106 (“medium” in step T106), the control unit 600 drives the first heating device 512 and the second heating device 420B. A signal is output and the 1st heating apparatus 512 and the 2nd heating apparatus 420B are driven (step T110).

  When the ink ejection amount per page is “many” in step T106 (“many” in step T106), the control unit 600 performs the first heating device 512, the second heating device 420B, and the third heating. A drive signal is output to the device 340 to drive the first heating device 512, the second heating device 420B, and the third heating device 340 (step T108).

  Then, after a predetermined time has elapsed, the control unit 600 controls each unit that executes printing such as the carriage 200A, the print head 500, and the transport mechanism, and causes printing to be performed (step T114). The predetermined time is a time required for the ink temperature at the heated portion to reach a set temperature (for example, 35 ° C.), and is determined in advance.

  When printing for one page is completed, control unit 600 determines whether there is next print data (step T116). If the controller 600 determines that there is next print data (for example, print data for the second page), the control unit 600 returns to step T104. On the other hand, if there is no next print data, the control unit 600 ends this routine.

  In the ink jet printer 1100B in the present embodiment, unlike the ink jet printer 1100A in the first embodiment, the driving number of the heating device is changed in accordance with the ink ejection amount per page. When the amount of ink ejected per page is “small”, the amount of ink used to print one page is smaller than the amount of ink in the print head 500. Accordingly, by driving only the first heating device 512 provided in the print head 500 and reducing the viscosity of the ink in the print head 500 before starting printing, one page is printed. It is possible to improve the stability of ink ejection (ejection).

  When the ink ejection amount per page is “medium”, not only the ink in the print head 500 but also the ink in the supply path 400 is used to print one page. Therefore, not only the first heating device 512 provided in the print head 500 but also the second heating device 420B is driven to reduce the viscosity of the ink in the print head 500 and the supply path 400 before starting printing. By doing so, it is possible to improve the stability of ink ejection (ejection) while printing one page.

  When the amount of ink ejected per page is “large”, the ink in the print head 500, the supply path 400, and the sub tank 300 is also used to print one page. Accordingly, the first heating device 512, the second heating device 420B, the third heating device 340, and all the heating devices are driven to reduce the ink in the print head 500, the supply path 400, and the sub tank 300 before starting printing. By increasing the viscosity, it is possible to improve the stability of ink ejection (ejection) while printing one page.

  As described above, according to the ink jet printer 1100B of the present embodiment, for example, even when a character page is printed by changing the driving number of the heating device according to the ink ejection amount per page, a photo page is also printed. In the case of printing the ink, it is possible to appropriately reduce the viscosity of the ink and to improve the stability of ink ejection (ejection).

  Further, since the ink jet printer 1100B of this embodiment warms a necessary amount of ink before starting printing, the heating device is controlled based on the ink temperature during printing as in the first embodiment. not going. Therefore, the circuit configuration of the control unit 600 can be simplified.

D. Third embodiment:
FIG. 9 is an explanatory diagram conceptually showing the structure of the main part of an ink jet printer as a third embodiment of the present invention. The configuration of the ink jet printer 1100C of the present embodiment is different from that of the ink jet printer 1100B of the second embodiment in that the third heating device 340 and the second heating device 420B are not provided. That is, the ink jet printer 1100C in the present embodiment includes one heating device (first heating device 512). The other components of the ink jet printer 1100C are the same as those in the second embodiment. Therefore, the same components as those in the second embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  In addition, with the difference in these configurations, the flow of ink heating control in the control unit 600 is also different. FIG. 10 is a flowchart showing a control routine of the heating device executed in the control unit in the present embodiment. This routine is executed when the power of the inkjet printer 1100C is turned on.

  When a print command is input from the external device (step T102), the control unit 600 calculates an ink ejection amount per page based on the print data input from the external device together with the print command (step U104).

  The control unit 600 determines whether or not the ink ejection amount per page calculated in step U104 is larger than a preset amount than the preset amount (step U106). In this embodiment, the ink amount in the print head 500 is set as the set amount.

  In step U106, when the ink ejection amount per page is larger than the set amount (YES in step U106), the control unit 600 outputs a drive signal to the first heating device 512, and first The heating device 512 is heated for 3 seconds (step U108).

  On the other hand, when the ink ejection amount per page is equal to or smaller than the set amount in step U106 (NO in step U106), control unit 600 outputs a drive signal to first heating device 512, and the first The 1 heating device 512 is heated for 1 second (step U110).

  In this embodiment, the control unit 600 executes printing by executing a print control routine that controls each unit that executes printing, such as the carriage 200A, the print head 500, and the conveyance mechanism, separately from this routine. When a print command is input from an external device, the control unit 600 outputs a control signal to each of the above-described units to start printing after 1 second has elapsed since heating in the first heating device 512 is started. When printing for one page is completed, the control unit 600 turns on a print end flag stored in advance in the memory 604. When starting the next printing, the control unit 600 turns off the print flag.

  That is, in the inkjet printer 1100C of the present embodiment, printing is started after short-time heating is completed. Therefore, when the ink ejection amount per page is larger than the set amount, heating is continued for 2 seconds after printing is started.

  When heating is completed in the control routine of the heating device, control unit 600 determines whether printing for one page has been completed (step U112). Specifically, when the print end flag described in memory 604 is ON (YES in step U112), control unit 600 proceeds to step U114 and determines whether there is next print data. (Step U114).

  On the other hand, when the print end flag described in memory 604 is OFF (NO in step U112), control unit 600 returns to step U112. That is, control unit 600 repeats step U112 until printing for one page is completed.

  If the control unit 600 determines in step U114 that there is next print data (for example, print data for the second page), the process returns to step U104. On the other hand, if there is no next print data, the control unit 600 ends this routine.

  According to the ink jet printer 1100C in the present embodiment, the heating time is changed according to the ink ejection amount per page. For example, when the ink ejection amount per page is smaller than the ink amount in the print head 500, ink in the print head 500 is preliminarily warmed to discharge ink during printing of one page ( The stability of injection) can be improved. On the other hand, when the amount of ink ejected per page is larger than the amount of ink in the print head 500, the ink flowing into the print head 500 is also warmed to discharge ink during printing for one page. The stability of (injection) can be improved. Therefore, by changing the heating time according to the ink ejection amount per page, for example, when printing a character page or a photo page, it is possible to appropriately reduce the viscosity of the ink. In addition, the stability of ink ejection (ejection) can be improved.

E. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

(1) In the above embodiment, print data is input from an external device. For example, an ink jet printer has an external memory interface, and the print data is an external memory such as a USB memory, an SD memory card, or a memory stick. It may be configured to be input from. A scanner, a digital camera, or the like may be used as the external device.

(2) In the above embodiment, the ink jet printer is exemplified as the liquid ejecting apparatus. However, the present invention is not limited thereto, and the present invention includes a liquid ejecting unit that ejects liquid, such as a manufacturing apparatus for a color filter such as a liquid crystal display. The present invention can be applied to various liquid ejecting apparatuses.

(3) In the above embodiment, the control unit 600 controls the heating and cooling of the ink based on the ink ejection amount per page. For example, the amount of ink supplied to the print head 500, the dots The heating / cooling of the ink may be controlled based on information representing the ink ejection amount, such as the number.

(4) In the above embodiment, the control unit 600 shows an example of controlling the heating / cooling of the ink based on the print data. For example, a flow sensor is provided in the ink cartridge, and per unit time. The flow rate of ink flowing out from the ink cartridge may be detected, and heating / cooling of the print head 500 may be controlled based on the detection result.

(5) In the above embodiment, the flow rate of ink is expressed using the ink ejection amount per page, and the cooling device and the heating device are controlled based on the ink ejection amount per page. It is not limited to the ink ejection amount per page, and the cooling / heating device and the heating device can be controlled based on various information indicating the flow velocity. For example, when the user issues a print command for 10 pages as 1 Job, the cooling / heating device and the heating device may be controlled based on the ink ejection amount per 10 pages (per 1 Job). Alternatively, one page may be divided into a plurality of parts and controlled based on the ink ejection amount per division unit. The ink ejection amount per main scan may be used, or the ejection amount per ejection may be controlled based on the ejection amount. Further, the control may be performed based on the injection amount per unit time (for example, 1 ms).

(6) In the second embodiment, an example is shown in which driving of each heating device is terminated before starting printing. However, the heating device is driven according to the ink ejection amount per page even during printing. You may perform control which continues.

(7) In the above embodiment, the case where the supply path cooling / heating device is provided and the case where the heating device is provided are exemplified, but the heating device and the cooling device may be provided separately.

(8) The flow of control of the cooling / heating device and the heating device is not limited to the above embodiment. You may combine the content of control of the said 1st-3rd Example. For example, in the control of the heating device in the second and third embodiments, the control based on the ink temperature may be performed in combination as in the first embodiment. Further, the heating temperature, the heating time, the number of heating devices, and the set amount are not limited to the above embodiment.

(9) The arrangement of the heating device is not limited to the above embodiment. The ink supply tube 210 and the ink cartridge 100 may be provided. FIG. 11 is a schematic diagram illustrating the configuration of the ink cartridge and the arrangement of the heating device and the temperature detection unit. The ink cartridge 100 is partitioned into an ink chamber 104 and a buffer chamber 106. The ink chamber 104 communicates with the atmosphere opening hole 102 for introducing the atmosphere into the ink cartridge 100. The buffer chamber 106 communicates with the ink supply port 110, and the ink in the ink cartridge 100 flows into the ink supply tube 210 through the ink supply port 110. The ink chamber 104 and the buffer chamber 106 communicate with each other via a communication path 108. The communication path 108 has a function of capturing bubbles mixed in the ink and suppressing the bubbles from mixing into the ink downstream of the communication path 108.

  As shown in FIG. 11, the heating device 112 is provided in contact with the bottom surface of the buffer chamber 106 and heats ink in the buffer chamber 106 and the ink chamber 104. When the temperature detection unit 114 detects the ink temperature in the buffer chamber 106 and transmits it to the control unit 600, the control unit 600 can control the heating device 112 based on the ink temperature in the buffer chamber 106. .

(10) In the above embodiment, the ink storage unit includes the ink cartridge 100, the ink supply tube 210, the sub tank 300, the supply path 400, and the print head 500. However, the configuration of the ink storage unit is the same as the above embodiment. It is not limited. For example, the sub tank 300 may not be provided.

(11) The heating device and the cooling device are not limited to the above-described embodiments. As the heating device, for example, a device that heats by heat irradiation such as a halogen lamp or an infrared lamp may be used. Moreover, you may make it the structure which provides a warm water path and heats with the heat of warm water. Moreover, as a cooling device, you may make it the structure which provides a cooling water path and radiates heat with cooling water.

(12) In the first embodiment, the control for cooling when the temperature of the ink becomes higher than [set temperature + 5 ° C.] is exemplified. However, for example, the ink is not provided with a cooling device. A configuration may be adopted in which heating is stopped when the temperature becomes higher than [set temperature + 5 ° C.].

  DESCRIPTION OF SYMBOLS 100 ... Ink cartridge, 102 ... Air release hole, 104 ... Ink chamber, 106 ... Buffer chamber, 108 ... Communication path, 110 ... Ink supply port, 112 ... Heating device, 114 ... Temperature detection part, 200 ... Carriage, 200A ... Carriage , 200B ... Carriage, 210 ... Ink supply tube, 220 ... Cartridge storage, 300 ... Sub tank, 321 ... Ink introduction path, 322 ... Ink supply chamber, 323 ... Pressure chamber, 324 ... Ink lead-out path, 325 ... Flow path, 330 ... Opening / closing member, 332 ... spring part, 334 ... lid part, 336 ... seal ring, 340 ... third heating device, 352 ... film member, 354 ... pressure receiving plate, 400 ... supply path, 420A ... supply path cooling / heating apparatus, 420B ... Second heating device, 500 ... print head, 502 ... flow path in head, 504 ... common ink chamber, 505 ... 506 ... Pressure chamber, 508 ... Nozzle opening, 509 ... Actuator chamber, 510 ... Piezo element, 511 ... Vibrating plate, 512 ... First heating device, 514 ... Head temperature detection unit, 600 ... Control unit, 602 ... CPU, 604 ... memory, 606 ... input / output port, 1000A, 1000B, 1100A, 1100B, 1100C ... inkjet printer, PP ... printing paper

Claims (8)

A liquid ejecting apparatus,
A liquid reservoir for storing liquid;
A liquid ejecting section that ejects the liquid supplied from the liquid storage section;
A heating unit for heating the liquid;
A control unit for controlling the heating unit;
With
The controller is
A liquid ejecting apparatus that controls the heating unit based on a flow rate of the liquid supplied from the liquid storage unit to the liquid ejecting unit. The liquid ejecting apparatus according to claim 1,
A temperature-related information acquisition unit that acquires information about the temperature of the liquid;
The controller is
A liquid ejecting apparatus that controls the heating unit based on the flow rate of the liquid and the temperature-related information acquired by the temperature-related information acquisition unit. The liquid ejecting apparatus according to claim 2,
A cooling unit for cooling the liquid;
The controller is
A liquid ejecting apparatus that controls the cooling unit based on the temperature-related information. The liquid ejecting apparatus according to claim 1,
The controller is
A liquid ejecting apparatus that controls the liquid ejecting unit based on image data representing an image and derives the flow velocity of the liquid based on the image data. A liquid ejecting apparatus,
A liquid reservoir for storing liquid;
A liquid ejecting section that ejects the liquid supplied from the liquid storage section;
A heating unit for heating the liquid;
A control unit for controlling the heating unit;
With
The controller is
A liquid ejecting apparatus that controls the liquid ejecting unit based on image data representing an image and controls the heating unit based on the image data. A liquid ejecting unit comprising: a liquid storing unit that stores liquid; a liquid ejecting unit that ejects liquid supplied from the liquid storing unit; a heating unit that heats the liquid; and a control unit that controls the heating unit. A control method for controlling an apparatus, comprising:
A control method of a liquid ejecting apparatus, comprising: a step of controlling the heating unit based on a flow rate of the liquid supplied from the liquid storage unit to the liquid ejecting unit. A program for causing a computer to control a liquid ejecting apparatus that includes a liquid storing unit that stores liquid, a liquid ejecting unit that ejects liquid supplied from the liquid storing unit, and a heating unit that heats the liquid. There,
The program which makes the said computer implement | achieve the function which controls the said heating part based on the flow velocity of the said liquid supplied to the said liquid injection part from the said liquid storage part.   A computer-readable storage medium in which the program according to claim 7 is stored.

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