JP2023001349A - liquid injector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid ejecting apparatus that can stabilize temperature of ink supplied to a head.

SOLUTION: A liquid ejecting apparatus includes: a liquid ejecting head 31 which has nozzles Nz for ejecting liquid and can move in a predetermined direction; a plurality of liquid channels 12 in which the liquid supplied to the liquid ejecting head 31 flows; and heating parts 25 and 26 which heat the liquid in the liquid channels 12. The liquid channel 12 includes: a circulation path 60 where the liquid supplied to the liquid ejecting head 31 is ejected from the liquid ejecting head 31 without passing through the nozzles Nz, and is made to circulate to upstream sides of the heating parts 25 and 26; and a non-circulation path where the liquid supplied to the liquid ejecting head 31 is ejected from the liquid ejecting head 31 without passing through the nozzles Nz, and is not made to circulate to the upstream sides of the heating parts 25 and 26. The circulation path 60 is arranged at an end in a moving direction of the liquid ejecting head 31.

SELECTED DRAWING: Figure 3

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present invention relates to liquid ejecting apparatuses.

2. Description of the Related Art Inkjet printers are known as one type of recording apparatus that records images, characters, and the like by ejecting liquid onto a recording medium. In this ink jet printer, for example, when applying an ink having a relatively high viscosity, it is important to control the viscosity of the ink in order to obtain good ink ejection characteristics. Therefore, there is a technology that stabilizes the ink jetting characteristics by providing a fluid flow path through which the fluid for heating the ink flows in the head, keeping the temperature of the ink almost uniform, and maintaining a constant ink viscosity. (See, for example, Patent Document 1).

JP-A-2008-55716

However, in the above-described prior art, there is a problem that the head is cooled by the wind blowing as the head moves, and the temperature of the ink drops.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid ejecting apparatus capable of stabilizing the temperature of ink supplied to a head.

In order to solve the above-described problems, a liquid ejecting apparatus of the present invention provides a liquid ejecting unit having a plurality of nozzles for ejecting liquid, and a liquid flow path through which the liquid supplied to the nozzles flows. and a carriage that holds the liquid ejecting portion and reciprocates in a width direction that intersects the transport direction in which the medium is transported, wherein the carriage includes the meandering flow channel. a first heating unit having a heater that heats the liquid in the meandering flow path through a metal member that constitutes the first heating unit; A liquid storage section and a second heating section positioned above the nozzle for heating the liquid stored in the liquid storage section are provided, and the heater is fixed to the metal member. Characterized by

Moreover, in the liquid ejecting apparatus, it is preferable that the metal member is made of stainless steel.

Further, in the above liquid ejecting apparatus, it is preferable that the heater is made of a film material in which resistance heating wiring is embedded, and is directly attached to the metal member.

Further, in the above-described liquid ejecting apparatus, the meandering flow path portion is positioned above the liquid storage portion, and the heater of the first heating portion and the heater of the second heating portion are connected to the carriage. preferably away from the inner wall of the

Further, in the above liquid ejecting apparatus, it is preferable that the liquid reservoir is configured by a pressure adjustment section that adjusts the pressure of the liquid supplied to the nozzle.

Further, in the liquid ejecting apparatus, the liquid ejecting section has a plurality of nozzle rows in which a plurality of the nozzles are arranged, and the liquid flow paths are provided in a plurality corresponding to the plurality of the nozzle rows. It is preferable that the plurality of pressure adjusting portions provided corresponding to the nozzle rows are arranged in the width direction with a gap therebetween.

Moreover, in the liquid ejecting apparatus, it is preferable that the second heating section is arranged in a horizontal direction with respect to the pressure adjusting section.
Further, in the liquid ejecting apparatus, a light-emitting section that irradiates the medium with ultraviolet rays is provided at a position away from the carriage downstream in the transport direction, and the carriage is positioned in the width direction with respect to the light-emitting section. is preferably moved relative to
Further, in the above liquid ejecting apparatus, it is preferable that the pressure adjusting portion has a dimension in the direction of gravity and the direction of transport that is longer than the dimension in the width direction.

1 is a perspective view showing a printer according to a first embodiment; FIG. 1 is a cross-sectional view showing a schematic configuration of a printer according to a first embodiment; FIG. FIG. 2 is a diagram conceptually showing an ink supply path of the printer according to the first embodiment; 3 is a diagram showing the detailed configuration of ink flow paths around the inkjet head according to the first embodiment; FIG. It is a figure which shows the positional relationship of the 2nd heat source and pressure adjustment part which concern on 1st Embodiment. It is a figure which shows the structure which concerns on the 2nd flow path part which concerns on 1st Embodiment, and a 1st heat source. FIG. 10 is a diagram showing a detailed configuration of ink flow paths around the inkjet head according to the second embodiment;

Hereinafter, each embodiment of the recording apparatus according to the present invention will be described with reference to the drawings. In addition, in each drawing used for the following description, the scale of each member is appropriately changed so that each member has a recognizable size.
In this embodiment, an ink jet printer (hereinafter simply referred to as printer 1) is exemplified as a liquid ejecting apparatus according to the present invention.

(First embodiment)
FIG. 1 is a perspective view showing the appearance of a printer 1 according to this embodiment. FIG. 2 is a cross-sectional view showing a schematic configuration of the printer 1. As shown in FIG.

A printer (recording device) 1 is a large format printer (LFP) that handles media M of relatively large size. The medium M is, for example, a strip-shaped medium having a width of about 64 inches (Inch), and is formed of, for example, vinyl chloride film or paper.

As shown in FIGS. 1 and 2, the printer 1 includes a transport unit 2 that transports the medium M in a roll-to-roll manner, and a liquid ink (for example, ultraviolet curable ink) that is ejected onto the medium M. It has a recording unit 3 for recording images, characters, etc., and a processing unit 4 for curing the ink jetted onto the medium M by irradiating it with ultraviolet rays. Each of these components is supported by the body frame 5 .

The conveying unit 2 includes an unwinding unit 21 that feeds out the medium M wound in a roll shape, a winding unit 22 that winds up the fed-out medium M in a roll shape, and between the unwinding unit 21 and the winding unit 22 . and a pair of transport rollers 23 that hold the medium M on the transport path and apply a transport force. The unwinding section 21, the winding section 22, and the conveying roller pair 23 are driven by a motor and speed reducer (not shown).

The recording unit 3 includes an inkjet head 31 that ejects ink onto the medium M on a transport path on the downstream side of the transport roller pair 23, and a carriage 32 that mounts the inkjet head 31 and is capable of reciprocating in the width direction. . The inkjet head 31 has a plurality of nozzles NZ (see FIG. 3), and is configured to be able to eject ultraviolet curable ink that is selected in relation to the medium M and requires ultraviolet irradiation. The inkjet head 31 is capable of ejecting a plurality of colors (five colors in this embodiment) of ink, and has five rows of nozzles for ejecting each color of ink.

Inside the inkjet head 31, there are formed pressure generating chambers that accommodate ink ejected from the nozzles Nz as ink flow paths, a common ink chamber communicating with the pressure generating chambers in common, and the like. Ink supplied from the pressure adjustment unit 30 to the inkjet head 31 is supplied to each pressure generation chamber via a common ink chamber, and ink droplets are ejected from the nozzles Nz due to pressure fluctuations in the pressure generation chambers. there is

The UV curable ink is mainly composed of a resin material, a photopolymerization initiator as a curing agent, a solvent or a dispersion medium. A functional liquid having a unique function can be formed by adding a dye such as a pigment or a dye, or a functional material such as a lyophilic or liquid-repellent surface modifying material to this main material. In this embodiment, for example, cyan, magenta, yellow, and white pigments are added. The resin material of the ink is a material that forms a resin film. The resin material is not particularly limited as long as it is liquid at room temperature and becomes a polymer by polymerization. Furthermore, resin materials with low viscosity are preferred, preferably in the form of oligomers. More preferably, it is in the form of a monomer. The photopolymerization initiator is an additive that acts on the crosslinkable groups of the polymer to promote the crosslinking reaction. For example, benzyl dimethyl ketal can be used as the photopolymerization initiator. The solvent or dispersion medium adjusts the viscosity of the resin material.

The medium support section 10 constitutes a part of the transport path of the medium M, and is configured to bend the medium M upwardly and support it between the unwinding sections 21 and 22 . there is

The processing unit 4 has an ultraviolet irradiation unit 43 that irradiates the medium M with ultraviolet rays on the downstream side in the transport direction of the position where the recording unit 3 is provided.
The ultraviolet irradiation section 43 has a light emitting section 43a for irradiating ultraviolet rays and a reflector 43b.

A large number of LED (Light Emitting Diode) elements are arranged in the light emitting portion 43a. This LED element is an element that receives power supply and emits ultraviolet light, which is ultraviolet light. The reflecting plate 43b is for reflecting the ultraviolet rays emitted from the light emitting section 43a and irradiating the recording surface of the medium M with the ultraviolet rays intensively.

By the way, the printer 1 according to the present embodiment ejects high-viscosity ultraviolet curing ink. In order to eject such high-viscosity ink from the inkjet head 31, it is necessary to reduce the viscosity by heating. Heating the ink means raising the temperature of the ink to a certain temperature.

In this embodiment, the ink supplied to the inkjet head 31 is heated to adjust the temperature to a predetermined temperature, and the viscosity of the ink is lowered so that the ink can be ejected from the inkjet head 31 with high accuracy. Specifically, in this embodiment, the temperature of the ink is heated to, for example, 35.degree.

FIG. 3 is a diagram conceptually showing the ink supply path of the printer 1 according to this embodiment.
As shown in FIG. 3, the ultraviolet curable ink stored in the ink cartridge 50 is mounted on the carriage 32 (recording section 3) via a plurality of (four in this embodiment) ink flow paths 11. It is supplied to the inkjet head 31 . A plurality of (four in this embodiment) ink cartridges 50 are provided corresponding to the ink colors ejected from the inkjet head 31 . In this embodiment, the ink cartridge 50 is composed of four ink cartridges 50C, 50M, 50Y and 50W containing cyan, magenta, yellow and white inks, respectively.

The ink channel 11 includes a first channel portion 11a, a second channel portion 11b, and a third channel portion 11c. The first channel portion 11 a is composed of a plurality of flexible tubes 12 , each of which is connected to the ink cartridge 50 at one end. The second flow path portion 11 b is heated by a first heat source (heating portion) 25 , and the third flow path portion 11 c is heated by a second heat source (heating portion) 26 .

In the printer 1, the first heat source 25 and the second heat source 26 are provided in the carriage 32 in a sealed state. Thereby, the heat of the first heat source 25 and the second heat source 26 is efficiently transmitted to the ink flow path 11 (the second flow path portion 11b and the third flow path portion 11c). The heating efficiency of the ink flow path 11 may be improved by circulating the atmosphere inside the carriage 32 .

The second flow path portion 11b is composed of the flat flow path 13 in which the ink flowing inside is heated by the first heat source 25 . The third channel portion 11 c is configured by a pressure adjusting portion 30 provided between the flat plate channel 13 and the inkjet head 31 .

The pressure adjusting portion 30 is formed using a resin material such as polypropylene. The pressure adjustment unit 30 has an ink chamber that is partitioned by an elastic sheet and whose volume changes according to external pressure. This elastic sheet is deformable in the directions of contracting and expanding the ink chamber. Then, the pressure fluctuation of the ink is absorbed by the damper function due to the deformation of the elastic sheet. That is, the pressure adjusting portion functions as a pressure damper due to the action of the elastic sheet. Therefore, the ink is supplied to the inkjet head 31 side in a state in which the pressure fluctuation is absorbed in the pressure adjusting section 30 . In other words, the pressure adjustment section constitutes a liquid storage section that can temporarily store the ink to be supplied to the inkjet head 31 .

FIG. 4 is a diagram showing the detailed configuration of the ink flow path around the inkjet head 31. As shown in FIG. As shown in FIG. 4, the printer 1 according to this embodiment includes five pressure adjustment units 30 corresponding to ink colors contained in the ink cartridges 50 . Specifically, the printer 1 according to this embodiment has pressure adjustment units 30C, 30M, 30Y, 30W1, and 30W2.

The pressure adjustment portion 30C is supplied with ink from the ink cartridge 50C, the pressure adjustment portion 30M is supplied with ink from the ink cartridge 50M, and the pressure adjustment portion 30Y is supplied with ink from the ink cartridge 50Y. It is.

In addition, the pressure adjusting portions 30W1 and w2 are supplied with ink from the ink cartridge 50W. The pressure adjustment units 30W1 and 30W2 to which white ink is supplied are arranged so as to sandwich the pressure adjustment units 30C, 30M and 30Y to which other color (cyan, magenta, and yellow) inks are supplied.

The inks (cyan, magenta, and yellow inks) in the ink cartridges 50C, 50M, and 50Y pass through the tube 12 that constitutes the first channel portion 11a of the ink channel 11, and the pressure adjustment portions 30C, 30M, and 30Y. supplied to the inkjet head 31 via the These inks of each color supplied into the inkjet head 31 are appropriately supplied to pressure generating chambers through common ink chambers in the head, and are jetted from the nozzles Nz.

On the other hand, in the present embodiment, the ink (white ink) in the ink cartridge 50W passes through the ink tube 61 that constitutes the first channel portion 11a of the ink channel 11 and passes through the pressure adjustment portion 30W1 or 30W2. is supplied to the inkjet head 31 via the .

The printer 1 includes a second heat source 25 capable of heating the ink in the pressure adjustment section 30 forming the third flow path section 11 c between the first heat source 25 and the inkjet head 31 . The second heat source 26 has a heater 26a and a fan 26b that supplies the air warmed by the heater 26a to the pressure adjustment section 30 (third flow path section 11c).

As a result, the ink temporarily stored in the pressure adjustment section 30 can be heated. Therefore, the ink sent from the pressure adjustment unit 30 to the inkjet head 31 side is maintained at a predetermined viscosity, so that the ink flows smoothly through the ink flow path in the pressure adjustment unit 30, and is supplied to the inkjet head 31 satisfactorily. It will be done.

FIG. 5 is a diagram showing the positional relationship between the second heat source 26 and the pressure regulators 30C, 30M, 30Y, 30W1 and 30W2.
As shown in FIG. 5, the five pressure adjustment units 30 are attached to the inkjet head 31 with a gap between them. In the second heat source 26, the fan 26b supplies outside air heated by the heater 26a to the pressure adjustment section 30 side.

In the present embodiment, the pressure adjustment units 30 are arranged so as to be parallel to the blowing direction of the fan 26b, and a gap is provided between the adjacent pressure adjustment units 30. Therefore, the warm air from the fan 26b is can be applied efficiently. As a result, the ink in the pressure adjustment section 30 can be efficiently heated and maintained at a predetermined temperature (35° C.).

By the way, in the printer 1 , ink heated by the first heat source 25 and the second heat source 26 is supplied to the inkjet head 31 . However, air in the printer 1 hits the inkjet head 31 when the carriage 32 moves. The air inside the printer 1 is not at 35° C., and the inkjet head 31 is cooled. Therefore, the temperature of the ink supplied to the inkjet head 31 is lowered, and the ink with increased viscosity may not be properly ejected from the nozzles NZ, which is a so-called ejection failure.

In this embodiment, an inkjet head 31 held by a carriage 32 (not shown) moves along the arrow direction shown in the figure. That is, the printer 1 is configured such that the inkjet head 31 can be moved along the arrangement direction of the plurality of pressure adjustment units 30 .

As shown in FIG. 4, the printer 1 according to the present embodiment discharges at least part of the ink supplied to the inkjet head 31 by the ink flow path 11 from the inkjet head 31 without passing through the nozzles Nz. It has a circulation path 60 for circulating to the upstream side of the heat source 25 of.

The circulation path 60 includes an ink tube 61 provided between the ink cartridge 50W and the first heat source 25 among the plurality of tubes 12 forming the first flow path portion 11a of the ink flow path 11, and the ink tube 61 and a pump (switching mechanism) 62 provided as a main component. The ink tube 61 has a branched portion 63 including a first branched portion 61a and a second branched portion 61b which are branched into two at the end on the first heat source 25 side. The first branch portion 61a communicates with the pressure adjustment portion 30W1 through the flat plate channel 13, and the second branch portion 61b communicates with the pressure adjustment portion 30W2 through the plate channel 13.

Based on such a configuration, the printer 1 supplies white ink from the ink cartridge 50W through the ink tube 61 to the inkjet head 31 via the first branch portion 61a and the pressure adjustment portion 30W1. The printer 1 can appropriately supply a part of the white ink supplied into the inkjet head 31 to the pressure generation chamber via the common ink chamber, and eject it from the nozzles Nz.

Further, the printer 1 can drive the pump 62 to make the circulation path 60 function.
For example, the circulation path 60 allows part of the white ink supplied to the inkjet head 31 via the pressure adjustment unit 30W1 to flow from the inkjet head 31 to the pressure adjustment unit only through the common ink chamber without passing through the pressure generating chamber and the nozzles Nz. Drain to 30W2. The ink discharged from the inkjet head 31 is returned to the first branch 61a via the pressure adjustment section 30W2, the second branch 61b, and the pump 62. FIG. The ink returned to the first branch portion 61a is again circulated to the inkjet head 31 via the first heat source 25 and the pressure adjustment portion 30W1.

Further, the first branch portion 61a and the second branch portion 61b that constitute the circulation path 60 connect the ink cartridges 50C, 50M, 50Y and the ink jet head 31 at least outside the carriage 32 to the tubes 12. It is arranged so as to sandwich. According to this configuration, the first branch portion allows ink at a stable temperature to flow through the first heat source 25 by circulating the tube 12, which is arranged in a region where the temperature is likely to decrease due to being exposed to the outside air outside the carriage 32. Insulation can be performed by 61a and the second branch portion 61b. The ink in the tube 12 can be heated outside the carriage 32 . Therefore, the heating time of the ink supplied to the first heat source 25 through the tube 12 can be shortened.

In addition, the printer 1 can change the direction of ink circulation in the inkjet head 31 by switching the driving of the pump 62 . Specifically, the printer 1 switches the driving of the pump 62 according to the moving direction of the inkjet head 31 as described later.

The printer 1 also has a temperature sensor 90 capable of detecting the temperature of the nozzle surface Nz1 on which the nozzles Nz of the inkjet head 31 are formed. It is switchable. According to this, in the case where the inkjet head 31 (carriage 32) is stopped, the printer 1 causes the circulation path 60 to function as necessary when the temperature of the nozzle surface Nz1 of the inkjet head 31 is lowered. The temperature inside the inkjet head 31 can be maintained.

The circulation path 60 passes a part of the white ink supplied to the inkjet head 31 via the pressure adjustment section 30W2 to the pressure adjustment section 30W1 from the inkjet head 31 to the pressure adjustment section 30W1 only through the common ink chamber without passing through the pressure generating chamber and the nozzles Nz. and can be discharged. The ink discharged from the inkjet head 31 is returned to the second branch portion 61b via the pressure adjustment portion 30W1 and the first branch portion 61a. The ink returned to the second branch portion 61b is again circulated to the inkjet head 31 via the first heat source 25 and the pressure adjustment portion 30W2.

As described above, the printer 1 circulates the white ink supplied to the inkjet head 31 to the upstream side of the first heat source 25 without ejecting part of the white ink from the nozzles NZ. The ink heated by 25 can be supplied to the pressure adjustment section 30W1 or 30W2.

Since the inkjet head 31 reciprocates along a predetermined direction, the printer 1 is in a state where the pressure adjusting units 30W1 and 30W2 are arranged on the leading side in the movement direction of the inkjet head 31 . Here, there is a risk that the temperature of the ink supplied to the inkjet head 31 will drop significantly on the head side in the moving direction of the head.

In the printer 1 according to the present embodiment, the flow path at the end located on the leading side in the movement direction of the inkjet head 31 is adapted to circulate. According to this, the ink heated by the first heat source 25 is circulated, so that the temperature drop of the ink in the inkjet head 31 is prevented.

Further, the pressure adjustment units 30C, 30M, and 30Y are sandwiched between the pressure adjustment units 30W1 and 30W2 in which the ink temperature is stabilized by circulating the ink through the circulation path 60. FIG. As a result, the ink is circulated while being heated in the end ink flow paths, whereas the ink is not circulated in the intervening ink flow paths. Therefore, although the temperature of the ink drops inside the ink jet head 31 at the end portion, the effect of the temperature drop can be reduced because the ink is sandwiched between the heat-circulated flow paths.

In addition, the white ink stored in the ink cartridge 50W has a characteristic that the pigment particles are more likely to settle than other color inks. On the other hand, the printer 1 according to the present embodiment employs a configuration in which the white ink is circulated inside the inkjet head 31 via the circulation path 60, so that the white ink does not settle inside the inkjet head 31. can be prevented from occurring.

6A and 6B are diagrams showing the configuration related to the second flow path portion 11b and the first heat source 25, and FIG. FIG. 6B is a cross-sectional view taken along an arrow, and FIG. 6B is a diagram showing a planar configuration of a metal plate that constitutes the flat plate flow path 13. As shown in FIG.

The flat plate flow path 13 is composed of a plurality of (five in this embodiment) grooves 14a formed in a metal plate 14 shown in FIG. 6(a). The metal plate 14 preferably has high thermal conductivity, and stainless steel is used in this embodiment. The grooves 14a formed in the metal plate 14 are connected to the plurality of tubes 12 forming the first flow path portion 11a through connecting portions 14b provided at one end. Further, the other end side of the groove 14a communicates with the above-described respective pressure adjusting portions 30C, 30M, 30Y, 30W1, and 30W2 which constitute the third flow path portion 11c in a region not shown (five in this embodiment). doing.

As shown in FIG. 6(a), the flat plate flow path 13 includes a metal plate 14 having a plurality of grooves 14a and a sealing plate (sealing member) for sealing the surface on which the grooves 14a are formed. ) 15 and a fixing plate 16 provided on the opposite side of the sealing plate 15 to the metal plate 14 . The metal plate 14 and the fixing plate 16 are fastened with screws in a region (not shown) while holding the sealing plate 15 therebetween. That is, the groove 14a is sealed by the fixed plate 16, and the fixed plate 16 and the groove 14a constitute the second flow path portion 11b.

The first heat source 25 is composed of a heater 25 a attached to the flat plate flow path 13 . The heater 25a is composed of, for example, a film material in which resistance heating wiring is embedded. Specifically, the heater 25 a is directly attached to the metal plate 14 . A heat insulating material 17 is attached to the surface of the heater 25a opposite to the metal plate 14. As shown in FIG. Thereby, the heat of the heater 25a is efficiently transmitted to the metal plate 14 side.

In this way, the grooves 14a formed in the metal plate 14 constitute the first flow path portion 11a, and the metal plate 14 is directly heated by the heater 25a. can be heated effectively. Therefore, the plurality of ink flow paths 11 formed by the plurality of grooves 14a can be efficiently heated by the same heat source (first heat source 25).

The printer 1 configured as described above operates as follows when a print start job command is input.
First, when the job command is input, the first heat source 25 (heater 25a) and the second heat source 26 (heater 26a, fan 26b) are driven, and the ink channel 11 (second channel portion 11b, second The ink in the 3 flow path portion 11c) is heated.

As described above, the present embodiment employs a two-stage heating method in which the upstream side of the ink flow path 11 is heated by the first heat source 25 and the downstream side of the ink flow path 11 is heated by the second heat source 26. The temperature of the ink supplied to the inkjet head 31 can be stabilized.

Then, when the temperature of the ink in the ink flow path 11 is maintained at a predetermined temperature, the medium M is conveyed to the printing area of the medium support section 10, and the inkjet head 31 of the recording section 3 prints on the medium M. Start. The inkjet head 31 performs printing while reciprocating in the width direction of the medium M while being mounted on the carriage 32 .

The light emitting unit 43a of the processing unit 4 irradiates the medium M onto which the ink has been jetted with ultraviolet rays. Since the ink used in the present embodiment is UV curable as described above and contains a photopolymerization initiator whose polymerization is initiated by UV rays, the surface is immediately solidified or cured. As a result, the ink is cured and fixed on the medium M. As shown in FIG. As described above, in this embodiment, since the ink droplets are cured by irradiating them with ultraviolet light immediately after being ejected onto the medium M, bleeding of the ink droplets is suppressed, and high-quality print processing with little bleeding can be performed.

Further, according to this embodiment, the ink circulated upstream of the first heat source 25 by the circulation path 60 is heated again and supplied to the inkjet head 31, so that the ink flowing through the circulation path 60 reaches a predetermined temperature. A heated state can be maintained. Therefore, the circulation path 60 (the first branch portion 61a and the second branch portion 61b) is arranged at the leading end of the plurality of ink flow paths 11 where the temperature is likely to decrease due to the movement of the inkjet head 31. Also in the configuration in which the moves, the temperature of the liquid supplied to the inkjet head 31 can be stabilized.

In addition, since the structure of the circulation path 60 can also be applied to countermeasures against sedimentation of white ink, it is possible to supply ink at a stable temperature to the inkjet head 31 and suppress the sedimentation of the white ink to provide a high value-added printer 1. can provide.

It should be noted that the present invention is not limited to the above embodiments, and can be modified as appropriate without departing from the gist of the present invention. For example, in the above-described embodiment, the printer 1 in which the plurality of pressure adjustment units 30 are arranged along the movement direction of the inkjet head 31 was illustrated, but the plurality of pressure adjustment units 30 are arranged along the direction perpendicular to the movement direction. The present invention can also be applied to the printer 1 that is used.

FIG. 7 is a diagram showing the detailed configuration of the ink flow path around the inkjet head 31 of the printer 1 according to this modification.
As shown in FIG. 7 , in this modified example, a circulation path 160 is provided for each of the plurality of pressure adjustment units 30 .

Here, the circulation path 160 provided in the pressure adjustment section 30W2 will be described as an example. The circulation paths 160 provided in the other pressure adjustment units 30W1, 30C, 30M, and 30Y have the same configuration.

The circulation path 160 mainly includes an ink tube 161 provided between the ink cartridge 50W and the first heat source 25 and a pump 162 provided in the ink tube 161 . The ink tube 161 has a branched portion 163 including a first branched portion 161a and a second branched portion 161b which are branched into two at the end on the first heat source 25 side. The first branch portion 161a and the second branch portion 161b communicate with the pressure adjustment portion 30W2 via the flat plate flow path 13, respectively.

Based on such a configuration, the printer 1 supplies white ink from the ink cartridge 50W via the ink tube 161 to the inkjet head 31 via the first branch portion 161a and the pressure adjustment portion 30W1. The printer 1 can appropriately supply a part of the white ink supplied into the inkjet head 31 to the pressure generation chamber via the common ink chamber, and eject it from the nozzles Nz.

Further, the printer 1 can drive the pump 162 to make the circulation path 160 function. For example, the circulation path 160 allows part of the white ink supplied to the inkjet head 31 via the pressure adjustment unit 30W2 to flow from the inkjet head 31 to the pressure adjustment unit only through the common ink chamber without passing through the pressure generating chamber and the nozzles Nz. Drain to 30W2. The ink discharged from the inkjet head 31 is returned to the first branch 161a via the pressure adjustment section 30W2, the second branch 161b, and the pump 162. FIG. The ink returned to the first branch portion 161a is again circulated to the inkjet head 31 via the first heat source 25 and the pressure adjustment portion 30W2.

Also in this modification, the printer 1 can switch the driving of the pump 162 based on the detection result of the temperature sensor 90 capable of detecting the temperature of the nozzle surface Nz1 on which the nozzles Nz of the inkjet head 31 are formed. ing.

In the printer 1 according to this modification, the ink in the outward path of the circulation path 160 is supplied to the ink tube 161 (the first branch portion 161a or the second branch portion 161b) arranged on the leading side in the movement direction of the inkjet head 31. I am trying to supply. Specifically, for example, when the inkjet head 31 moves diagonally downward to the left in FIG. do it.

According to this, the ink heated again by the first heat source 25 can be supplied through the circulation path 160 to the head side of the pressure adjustment section 30W2 in the moving direction, which is easily affected by the temperature drop of the internal space. A decrease in the temperature of the ink in the adjusting section 30W2 is prevented, and the temperature of the white ink supplied to the inkjet head 31 can be stabilized.

The printer 1 can similarly eject a portion of the ink supplied into the inkjet head 31 from the nozzles Nz for inks of other colors. In addition, by driving the pump 162 for the other circulation path 160, the ink can be discharged from the inkjet head 31 without going through the nozzle Nz, and can be circulated through the inkjet head 31 again.

According to the modified example described above, since the circulation path 160 is provided for each pressure adjustment unit 30, the temperature of the ink supplied to the inkjet head 31 can be stabilized. Also, in this modified example, two pressure adjusting units 30W1 and 30W2 corresponding to white ink are provided, but a configuration including only one pressure adjusting unit may be employed.

Moreover, in the above-described embodiment, the first heat source 25 and the second heat source 26 are provided, but either one of them may be provided, or three or more heat sources may be provided.
Further, the color of the ink ejected from the inkjet head 31 may be other colors different from those in the above embodiment. Further, in the above embodiment, the driving of the pump 162 is switched based on the detection result of the temperature sensor 90, but the temperature sensor 90 may not be used. Further, in the first embodiment, the case where the driving of the pump 162 can be switched has been illustrated, but the driving of the pump 162 may not be switched.

Further, in the present embodiment, the case where the recording apparatus is the printer 1 has been described as an example, but the present invention is not limited to this. Devices such as copiers and facsimiles may also be used.

Also, as the liquid ejecting apparatus, a recording apparatus that ejects or ejects a fluid other than ink may be employed. The present invention can be applied to, for example, various recording apparatuses equipped with a recording head that ejects minute droplets. Note that the term "droplet" refers to the state of the liquid ejected from the recording apparatus, and includes granular, tear-like, and string-like liquid. Further, the liquid referred to here may be any material that can be ejected by the printing apparatus. For example, it may be in a state when the substance is in a liquid phase, such as a high or low viscosity liquid, sol, gel water, other inorganic solvents, organic solvents, solutions, liquid resins, liquid metals (metal melts) ), and not only liquid as one state of matter, but also particles of functional materials made of solid matter such as pigments and metal particles dissolved, dispersed or mixed in a solvent. A representative example of the liquid is the ink (ultraviolet curable ink) described in the above embodiment, but if the viscosity is high, the liquid may not be the ultraviolet curable ink. In addition to paper and plastic films such as vinyl chloride films, the media M includes functional paper that is thin and thermally stretchable, substrates, metal plates, and the like. Moreover, the medium M is not limited to a belt-like shape, and may be a pre-cut recording medium.

1 printer (liquid ejecting device), 11 ink channel, 25 first heat source (heating unit), 26 second heat source (heating unit), 31 inkjet head, 32 carriage, 60, 160 circulation path, 61, 161 ink Tube, 62, 162 Pump (switching mechanism)

Claims (9)

a liquid injection unit having a plurality of nozzles for injecting liquid;
a liquid channel through which the liquid supplied to the nozzle flows, the liquid channel having a meandering channel portion;
a carriage that holds the liquid ejecting unit and reciprocates in a width direction that intersects the transport direction in which the medium is transported;
The carriage includes:
a first heating unit having a heater that heats the liquid in the meandering flow path through a metal member forming the meandering flow path;
a liquid reservoir that constitutes the liquid channel and stores the liquid that is supplied to the nozzle;
a second heating unit positioned above the nozzle and heating the liquid stored in the liquid storage unit;
The liquid ejecting apparatus according to claim 1, wherein the heater is made of a film material in which resistance heating wiring is embedded, and is directly attached to the metal member. 2. The liquid ejecting apparatus according to claim 1, wherein the metal member is made of stainless steel. The meandering flow path portion is positioned above the liquid storage portion, and the heater of the first heating portion and the heater of the second heating portion are separated from the inner wall of the carriage. 3. The liquid ejecting apparatus according to claim 1, wherein: 4. The liquid ejecting apparatus according to any one of claims 1 to 3, wherein the liquid reservoir includes a pressure adjustment section that adjusts the pressure of the liquid supplied to the nozzle. the liquid ejecting part has a plurality of nozzle rows in which a plurality of the nozzles are arranged;
A plurality of the liquid flow paths are provided corresponding to the plurality of the nozzle rows,
5. The liquid ejecting apparatus according to claim 4, wherein the plurality of pressure adjusting units provided corresponding to the plurality of nozzle rows are arranged in the width direction with a gap therebetween. 6. The liquid ejecting apparatus according to claim 4, wherein the second heating section is arranged in a horizontal direction with respect to the pressure adjusting section. 7. The liquid ejecting apparatus according to any one of claims 4 to 6, wherein the pressure adjustment portion has dimensions in the direction of gravity and in the transport direction that are longer than dimensions in the width direction. a light-emitting unit that irradiates the medium with ultraviolet rays at a position away from the carriage downstream in the conveying direction;
8. The liquid ejecting apparatus according to claim 1, wherein the carriage moves relative to the light emitting section in the width direction. a liquid injection unit having a plurality of nozzles for injecting liquid;
a liquid channel through which the liquid supplied to the nozzle flows, the liquid channel having a meandering channel portion;
a carriage that holds the liquid ejecting unit and reciprocates in a width direction that intersects the transport direction in which the medium is transported;
The carriage includes:
a first heating unit having a heater that heats the liquid in the meandering flow path through a metal member forming the meandering flow path;
a liquid reservoir that constitutes the liquid channel and stores the liquid that is supplied to the nozzle;
a second heating unit positioned above the nozzle and heating the liquid stored in the liquid storage unit;
The heater is fixed to the metal member,
The meandering flow path portion is positioned above the liquid storage portion, and the heater of the first heating portion and the heater of the second heating portion are separated from the inner wall of the carriage. and a liquid injection device.

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