JP2013220564A - Liquid injection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid injection device whose cost can be reduced and which can be made compact.SOLUTION: A liquid injection device includes a liquid injection head which injects a liquid, a storage part which has a first chamber and a second chamber partitioned off by a deformation part deforming according to an atmospheric pressure, and storing the liquid to be supplied to the liquid injection head in the first chamber, a pressurization part supplying gas pressurizing the second chamber, a supply path which connects the pressurization part to the second chamber and in which the gas flows, and a heating part provided to a part of the supply path and heating the gas flowing in the supply flow passage.

Description

  The present invention relates to a liquid ejecting apparatus.

  An ink jet printing apparatus is known as a liquid ejecting apparatus that ejects a liquid. As an ink jet printing device configuration, ink containing functional materials such as pigments, dyes, resins, and metal fine particles is temporarily stored, and pressure fluctuation of the temporarily stored ink is suppressed to the liquid ejecting head. A configuration including a pressurizing unit for supplying is known (for example, see Patent Document 1).

  In addition, for example, when ink having a relatively high viscosity is applied using a printing apparatus, it is important to manage the viscosity of the ink in order to obtain good ink ejection characteristics. Therefore, a technique is known in which a heating unit for heating ink is provided, the temperature of the ink is kept substantially uniform, and a constant ink viscosity is maintained (see, for example, Patent Document 2).

JP 2001-253085 A JP 2005-280246 A

  However, when both the pressurizing unit and the heating unit are mounted, it is necessary to mount different mechanisms separately, which increases the cost and may increase the size of the apparatus.

  In view of the circumstances as described above, it is an object of the present invention to provide a liquid ejecting apparatus that can be reduced in cost and size.

  The liquid ejecting apparatus according to the aspect of the invention includes a liquid ejecting head that ejects liquid, and a first chamber and a second chamber that are partitioned by a deforming portion that deforms according to atmospheric pressure, and is supplied to the liquid ejecting head. A storage section in which liquid is stored in the first chamber, a pressurizing section that supplies a gas that pressurizes the second chamber, a supply path that connects the pressurizing section and the second chamber, and through which the gas flows. And a heating unit that is provided in a part of the supply path and heats the gas flowing through the supply flow path.

  According to the present invention, the second chamber partitioned by the deforming portion that deforms according to the atmospheric pressure with the first chamber in which the liquid is stored, and the pressurizing unit that supplies the gas that pressurizes the second chamber; Since the heating part for heating the gas flowing through the supply flow path is provided in a part of the supply path through which the gas flows, the heated gas is supplied to the second chamber. As a result, heat is transmitted from the second chamber to the first chamber via the deforming portion, so that the liquid stored in the first chamber can be heated. Thus, by providing the pressurizing unit and the heating unit in one gas supply system, the pressurization and heating of the liquid can be performed efficiently. Thereby, compared with the case where a different mechanism is separately mounted, cost reduction and size reduction can be achieved.

The liquid ejecting apparatus preferably further includes a discharge path that is connected to the second chamber independently of the supply path and discharges the gas in the second chamber.
According to the present invention, since a discharge path for discharging the gas in the second chamber is further provided independently of the supply path, the gas is supplied from the supply path to the second chamber. In addition, the gas in the second chamber can be discharged. Thereby, replacement of the gas in the second chamber can be performed. Since the gas newly supplied to the second chamber is a gas heated by the heating unit, the heating of the liquid can be maintained by replacing the gas in the second chamber.

In the liquid ejecting apparatus, it is preferable that the discharge path has a circulation path that is connected to the pressurizing unit and returns the gas to the pressurizing unit.
According to the present invention, the discharge path has a circulation path that is connected to the pressurization unit and returns the gas to the pressurization unit, so that the gas discharged from the discharge path is sent again to the supply path by the pressurization unit, Will be supplied to the second chamber. In the heating unit, the gas that has already been heated and has a certain temperature rise is heated again, so that the burden on the heating unit can be reduced. In addition, the gas whose temperature is increased by heating circulates the entire system including the pressurizing unit, the supply path, the heating unit, the second chamber, the discharge path, and the circulation path. It will be.

The liquid ejecting apparatus preferably further includes a pressure adjusting unit that adjusts the pressure in the second chamber.
According to the aspect of the invention, since the pressure adjusting unit that adjusts the pressure in the second chamber is provided, the amount of the liquid supplied to the liquid ejecting head can be appropriately adjusted.

In the liquid ejecting apparatus, it is preferable that the pressure adjusting unit is provided in a part of a gas flow path connected to the second chamber.
According to the present invention, the range of design choices can be expanded by adopting a configuration in which the pressure adjusting portion is provided in a part of the gas flow path connected to the second chamber.

In the liquid ejecting apparatus, it is preferable that the liquid ejecting apparatus further includes a connection path that supplies at least a part of the gas heated by the heating unit to the liquid ejecting head.
According to the present invention, the liquid supplied to the liquid ejecting head can be heated by supplying at least a part of the gas heated by the heating unit to the liquid ejecting head.

In the liquid ejecting apparatus, it is preferable that the supply path is connected to the second chamber via the liquid ejecting head.
According to the present invention, since the supply path is connected to the second chamber via the liquid ejecting head, all of the gas heated by the heating unit is first supplied to the liquid ejecting head. The supplied liquid can be efficiently heated. Thereby, the discharge characteristic of the liquid can be stabilized.

1 is a diagram illustrating an overall configuration of a printing apparatus according to an embodiment of the present invention. FIG. 3 is a diagram illustrating a configuration of an ink supply unit of the printing apparatus according to the embodiment. FIG. 3 is a block diagram illustrating a configuration of a control unit of the printing apparatus according to the present embodiment. FIG. 5 is a diagram illustrating an aspect of an ink supply operation of the printing apparatus according to the embodiment. The figure which shows the structure of the ink supply which concerns on the modification of this invention. The figure which shows the structure of the ink supply which concerns on the modification of this invention. The figure which shows the structure of the ink supply which concerns on the modification of this invention. The figure which shows the structure of the ink supply which concerns on the modification of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating a schematic configuration of a printing apparatus PRT (liquid ejecting apparatus) according to the present embodiment. In the present embodiment, an ink jet printing apparatus will be described as an example of the printing apparatus PRT.

  The printing apparatus PRT shown in FIG. 1 is an apparatus that performs a printing process while conveying a sheet-like medium M such as paper or a plastic sheet. The printing apparatus PRT includes a housing PB, an inkjet unit IJ that ejects ink onto the medium M, an ink supply unit IS that supplies ink to the inkjet unit IJ, a transport unit CV that transports the medium M, and an inkjet unit IJ. A maintenance unit MN that performs the maintenance operation and a control unit CONT that controls these units.

  The housing PB is formed such that the transport direction of the medium M is the short direction, and the direction orthogonal to the transport direction of the medium M is the long direction. The casing PB is attached with the ink jet unit IJ, ink supply unit IS, transport unit CV, maintenance unit MN, and control unit CONT. A platen 13 is provided in the housing PB. The platen 13 is a support member that supports the medium M. The platen 13 is disposed in the longitudinal center of the housing PB. The platen 13 has a flat surface 13a directed to the ink jet unit IJ. The flat surface 13a is used as a support surface that supports the medium M.

  The transport unit CV includes a transport roller, a motor that drives the transport roller, and the like. The transport unit CV transports the medium M from the medium supply unit PB1 of the housing PB to the inside of the housing PB, and discharges the medium M from the medium discharge unit PB2 of the housing PB to the outside of the housing PB. The transport unit CV transports the medium M so that the medium M passes over the platen 13 inside the housing PB. The conveyance unit CV is configured such that the conveyance timing, conveyance amount, and the like are controlled by the control unit CONT.

  The ink jet unit IJ includes a head H that ejects ink and a head moving unit AC that holds and moves the head H. The head H reciprocates in the longitudinal direction of the housing PB (direction intersecting the transport direction of the medium M: first direction). The head H ejects ink toward the medium M sent onto the platen 13. The head H has a nozzle forming surface Ha on which a plurality of nozzles NZ from which ink is ejected are formed. The plurality of nozzles NZ are arranged side by side along the conveyance direction of the medium M, and constitute a nozzle row NL. The nozzle row NL is provided in a plurality of rows, for example, 4 rows in the first direction. The nozzle forming surface Ha is directed to the support surface 13 a of the platen 13.

  The head moving unit AC moves the head H in the longitudinal direction of the housing PB. The head moving unit AC has a carriage 4 for fixing the head H. The carriage 4 is in contact with a guide shaft 8 that extends in the longitudinal direction of the housing PB. The head moving unit AC includes a mechanism for moving the carriage 4 along the guide shaft 8, such as a pulse motor 9, a driving pulley 10, an idle pulley 11, a timing belt 12, and the like.

  The maintenance unit MN is provided in an area (home position) outside the area where printing is performed on the medium M. The maintenance unit MN includes a capping unit CP that covers the nozzle formation surface Ha of the head H, a wiping unit WP that wipes the nozzle formation surface Ha, and the like. A suction pump SC is connected to the capping unit CP. The waste ink discharged from the head H to the maintenance unit MN side is collected by a waste liquid collection mechanism (not shown).

  The ink supply unit IS supplies ink to the head H. A plurality of ink cartridges IC are accommodated in the ink supply unit IS. The printing apparatus PRT of the present embodiment has a configuration (off-carriage type) in which the ink cartridge IC is accommodated at a position different from the head H.

  The ink supply unit IS has a supply tube TB that connects the head H and the ink cartridge IC. The supply tube TB is provided for each ink cartridge IC. In the present embodiment, four ink cartridge ICs each containing different types of ink are provided. The four ink cartridges IC are connected to the four nozzle rows NL of the head H via the supply tube TB and the sub tank 2, respectively.

FIG. 2 is a diagram schematically illustrating the configuration of the ink supply unit IS.
As shown in FIG. 2, the ink cartridge IC has a first chamber 6a and a second chamber 6b that are partitioned by a deforming portion 6c that deforms according to the atmospheric pressure. The first chamber 6a stores ink and is connected to the head H via the supply tube TB. As the first chamber 6a, for example, an ink pack that can be deformed by a pressing force from the outside can be used. As the second chamber 6b, a bag-like member that expands by supplying a gas to the inside (refer to a one-dot chain line portion) and presses the ink pack by an expansion pressure can be used. By using such an ink pack or bag-like member, the ink cartridge IC is in a state in which the first chamber 6a and the second chamber 6b are partitioned by a deforming portion 6c that deforms according to the atmospheric pressure. .

  In addition to the ink cartridge IC, the ink supply unit IS includes a pressurizing pump 51 that pressurizes the second chamber 6b, and a supply pipe (supply path) that connects the pressurizing pump 51 and the second chamber 6b to flow gas. ) 52 and a heating unit 53 that is provided in a part of the supply pipe 52 and heats the gas flowing through the supply pipe 52.

  The pressurizing pump 51 sends compressed air to the supply pipe 52 under the control of the control unit CONT. The supply pipe 52 flows the gas sent from the pressurizing pump 51 to the second chamber 6b. A part of the supply pipe 52 is provided with a pressure adjustment unit 54 that adjusts the pressure inside the supply pipe 52. The pressure adjusting unit 54 includes, for example, a branch pipe 54a branched from the supply pipe 52, and an opening / closing valve 54b that adjusts the opening / closing of the branch pipe 54a.

  The heating unit 53 is attached to the supply pipe 52. The heating unit 53 heats the supply pipe 52 to transmit heat to the gas flowing through the supply pipe 52. The heating unit 53 is provided with a heating mechanism such as a heating wire mechanism. The heating temperature and heating timing by the heating unit 53 can be controlled by the control unit CONT.

FIG. 3 is a block diagram showing an electrical configuration of the printing apparatus PRT.
Connected to the control unit CONT are an input device IP for inputting various information related to the operation of the printing apparatus PRT, a storage device MR storing various information related to the operation of the printing apparatus PRT, and the like. A mobile unit AC, a maintenance unit MN, and the like are connected. The control unit CONT can control, for example, the capping unit CP, the suction pump SC, the pressurizing pump 51, the heating unit 53, the pressure adjusting unit 54, and the like in the maintenance unit MN.

  The head H has a piezoelectric vibrator provided for each nozzle NZ. The control unit CONT is connected to a drive signal generator that generates a drive signal input to the piezoelectric vibrator. The drive signal generator receives data indicating the amount of change in the voltage value of the ejection pulse input to the piezoelectric vibrator of the head H, and a timing signal that defines the timing for changing the voltage of the ejection pulse. The drive signal generator is provided so that a drive signal can be individually supplied to each piezoelectric vibrator.

  Next, the operation of the printing apparatus PRT configured as described above will be described. The control unit CONT performs a printing operation by the head H, an ink supply operation to the head H, and the like as operations of the printing apparatus PRT.

  When performing a printing operation using the head H, the control unit CONT places the medium M on the −Z side of the head H by the transport unit CV. After disposing the medium M, the control unit CONT inputs a drive signal from the drive signal generator related to the nozzle NZ to the piezoelectric vibrator based on the image data of the image to be printed while moving the head H. When a drive signal is input to the piezoelectric vibrator, the piezoelectric vibrator expands and contracts and ink is ejected from the nozzle NZ. A desired image is formed on the medium M by the ink ejected from the nozzles NZ.

  Next, when performing an ink supply operation to the head H, the control unit CONT sends a compressed gas having a predetermined pressure from the pressurizing pump 51 to the supply pipe 52. The compressed gas supplied to the supply pipe 52 flows through the supply pipe 52 and is supplied to the second chamber 6b of the ink cartridge IC. When gas is supplied to the second chamber 6b and the atmospheric pressure increases, the deforming portion 6c is deformed to the first chamber 6a side. The first chamber 6a is pressed by the pressure of this deformation, and a part of the ink stored in the first chamber 6a is sent from the supply tube TB to the head H.

  On the other hand, in the present embodiment, a heating unit 53 is provided in the supply pipe 52. Therefore, the control unit CONT causes the heating unit 53 to heat the supply pipe 52 before sending the compressed gas from the pressurizing pump 51. In this case, the sent compressed gas is heated by the supply pipe 52 and supplied to the second chamber 6b. For this reason, as shown in FIG. 4, in the second chamber 6b, the heat of the supplied gas A is transmitted to the ink Q in the first chamber 6a via the deforming portion 6c.

  Accordingly, the ink Q is heated, and the heated ink Q is sent to the supply tube TB and the head H by the deformation of the deformation portion 6c. Therefore, even when the viscosity of the ink Q is relatively high, it is possible to maintain a constant viscosity by heating the ink Q. Accordingly, it is possible to stably supply the ink Q from the ink cartridge IC to the head H.

  As described above, according to the present embodiment, the heating section 53 that heats the gas flowing through the supply pipe 52 is provided in a part of the supply pipe 52 that connects the second chamber 6b and the pressurizing pump 51. Therefore, the heated gas is supplied to the second chamber 6b. As a result, heat is transferred from the second chamber 6b to the first chamber 6a via the deforming portion 6c, so that the ink Q stored in the first chamber 6a can be heated. Thus, by providing the pressurization pump 51 and the heating unit 53 in one ink supply unit IS, the pressurization and heating of the ink Q can be efficiently performed. Thereby, compared with the case where a different mechanism is separately mounted, cost reduction and size reduction can be achieved.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, as shown in FIG. 5, a discharge portion 55 that discharges the gas in the second chamber 6 b may be connected to the second chamber 6 b independently of the supply pipe 52. The discharge part 55 has the discharge pipe 55a and the on-off valve 55b. The opening / closing of the on-off valve 55b can be controlled by the control unit CONT. With this configuration, the gas in the second chamber 6b can be discharged while the gas is supplied from the supply pipe 52 to the second chamber 6b. Thereby, exchange of the gas of the 2nd chamber 6b can be performed. Since the gas newly supplied to the second chamber 6b is a gas heated by the heating unit 53, the heating of the ink Q can be maintained by replacing the gas in the second chamber 6b.

  In addition, the discharge part 55 shown in FIG. 5 can serve as the pressure adjustment part which adjusts the pressure of the 2nd chamber 6b. For this reason, when the discharge part 55 is provided, the pressure adjustment part 54 is omissible. As described above, the pressure adjusting unit 54 may be provided in another part as long as it is a part of the gas flow path connected to the second chamber 6b.

  For example, as illustrated in FIG. 6, the discharge unit 55 may include a circulation pipe 55 c that is connected to the pressurization pump 51 and returns gas to the pressurization pump 51. In this case, the gas discharged from the discharge pipe 55 a is sent again to the supply pipe 52 by the pressurizing pump 51 and supplied to the second chamber 6 b through the heating unit 53. In the heating unit 53, since the gas that has already been heated and has a certain temperature rise is heated again, the burden is reduced. Further, the heated gas whose temperature is rising circulates in the entire system including the pressurizing pump 51, the supply pipe 52, the heating unit 53, the second chamber 6b, the discharge pipe 55a, and the circulation pipe 55c. The heating efficiency will be improved. The pressure adjusting unit 54 may be provided in the circulation pipe 55c.

  Alternatively, for example, as shown in FIG. In the configuration shown in FIG. 7, a connection pipe 56 is connected to the supply pipe 52, and the connection pipe 56 is connected to the head H. The connection pipe 56 is provided with an on-off valve 56a. The opening / closing of the on-off valve 56a can be controlled by the control unit CONT. With this configuration, since at least part of the gas heated by the heating unit 53 can be supplied to the head H, the ink Q supplied to the head H can be heated.

  As a configuration for supplying the gas heated by the heating unit 53 to the head H, for example, a configuration in which the supply pipe 52 is connected to the second chamber 6b via the head H as shown in FIG. According to this configuration, since all of the gas heated by the heating unit 53 is first supplied to the head H, the ink Q supplied to the head H can be efficiently heated. Thereby, the ejection characteristics of the ink Q can be stabilized.

  In the above-described embodiment, a printing apparatus that employs an inkjet method as a printing method has been described. However, the printing device can be changed to an arbitrary printing device such as an electrophotographic method or a thermal transfer method. Further, the recording apparatus is not limited to a printing apparatus, and may be another recording apparatus such as a FAX apparatus, a copying apparatus, or a multi-function machine having a plurality of functions. Further, as the recording apparatus, a liquid ejecting apparatus including a liquid ejecting head that ejects or ejects a small amount of liquid droplets other than ink may be employed.

  In addition, a droplet means the state of the liquid discharged from the said liquid ejecting apparatus, and shall also include what pulls a tail in granular shape, tear shape, and thread shape. The liquid here may be any material that can be ejected by the liquid ejecting apparatus. For example, it may be in a state in which the substance is in a liquid phase, such as a liquid with high or low viscosity, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts ) And a liquid as one state of a substance, as well as a material in which particles of a functional material made of a solid such as a pigment or metal particles are dissolved, dispersed or mixed in a solvent. Further, representative examples of the liquid include ink and liquid crystal as described in the above embodiment.

  Here, the ink includes general water-based inks and oil-based inks, and various liquid compositions such as gel inks and hot melt inks. As a specific example of the liquid ejecting apparatus, for example, a liquid containing a material such as an electrode material or a color material used for manufacturing a liquid crystal display, an EL (electroluminescence) display, a surface emitting display, a color filter, or the like in a dispersed or dissolved state. It may be a liquid ejecting apparatus, a textile printing apparatus, or the like.

  PRT ... Printer IJ ... Inkjet unit IS ... Ink supply unit H ... Head IC ... Ink cartridge TB ... Supply tube A ... Gas Q ... Ink 6a ... First chamber 6b ... Second chamber 6c ... Deformation unit 51 ... Pressure pump 52 ... Supply pipe 53 ... Heating part 54 ... Pressure adjustment part 55a ... Drain pipe 55c ... Circulation pipe 56 ... Connection pipe CONT ... Control part

Claims (7)

A liquid ejecting head for ejecting liquid;
A storage section in which the liquid supplied to the liquid jet head is stored in the first chamber;
A pressurizing section for supplying a gas for pressurizing the second chamber;
Connecting the pressurizing unit and the second chamber, a supply path through which the gas flows,
A liquid ejecting apparatus comprising: a heating unit that is provided in a part of the supply path and heats the gas flowing through the supply flow path. The liquid ejecting apparatus according to claim 1, further comprising a discharge path that is connected to the second chamber independently of the supply path and discharges the gas in the second chamber. The liquid ejecting apparatus according to claim 2, wherein the discharge path includes a circulation path that is connected to the pressurizing unit and returns the gas to the pressurizing unit. The liquid ejecting apparatus according to claim 1, further comprising a pressure adjusting unit that adjusts the pressure in the second chamber. The liquid ejecting apparatus according to claim 4, wherein the pressure adjusting unit is provided in a part of a gas flow path connected to the second chamber. The liquid ejecting apparatus according to claim 1, further comprising a connection path that supplies at least a part of the gas heated by the heating unit to the liquid ejecting head. The liquid ejecting apparatus according to claim 6, wherein the supply path is connected to the second chamber via the liquid ejecting head.

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