JP2009066901A - Fluid jet device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid jet device which inexpensively and easily suppresses water evaporation therefrom. <P>SOLUTION: The fluid jet device 1 for jetting a fluid L from a fluid jet head 3 having a plurality of nozzles 47 is provided with moisturizing parts 81 to 84 covering a part of or all of the outer surfaces of fluid flow-through sections 52, 34, 35, 15 and 127 where the fluid L is stored or let to flow. The fluid flow-through sections 52, 34, 35, 15 and 127 include at least one of the fluid jet head 3, a fluid supply system 35 to supply the fluid L to the fluid jet head 3 and a maintenance system 130 to suck and discharge the fluid L from the plurality of nozzles 47. The moisturizing parts 81 to 84 are configured to fill a covering part 53 covering at least a part of the fluid flow-through section 34, and also cavities 66 to 67 formed between the covering part 53 and the fluid flow-through section 34, with gel-type glycerin water solution moisturizer G. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluid ejecting apparatus.

  2. Description of the Related Art As an ink jet recording apparatus that improves the reliability of a printing operation when resuming a printing process after a long pause, there is known an ink jet recording apparatus that uses a gas barrier tube for a head cap (for example, Patent Document 1). . That is, a tube made of a material having an excellent gas barrier property is used as the first tube connected to the capping unit for sealing the nozzle forming surface of the ink jet recording head, and the second tube used for the tube pump constituting the negative pressure generating unit. A tube made of a material having high elasticity and restoring force is used as the tube, and the first and second tubes are connected by a connecting member. With this configuration, the moisture retention state by the ink solvent in the capping unit can be maintained for a long period of time, and the reliability of the printing operation can be improved in resuming printing after a long pause of the recording apparatus. is there.

Further, as similar to the ink jet recording apparatus, there is also known a fluid ejecting head capable of preventing drying of the ejected material present in the nozzle by an air curtain for preventing evaporation, and a moisture retention method thereof (Patent Document 2). . Specifically, the fluid ejecting head has a gas ejecting groove in at least a part of the periphery of the nozzle row including the nozzle openings. The gas injected from the gas injection groove forms an air curtain for separating the outside air existing in the nozzle exposed area where the nozzle opening is exposed to the outside air and the outside air existing outside the nozzle exposed area. That's it.
Japanese Patent Laid-Open No. 2000-14196 JP 2006-56116 A

However, the above-mentioned drying prevention method is intended to prepare the printing environment, suppress moisture evaporation in areas where moisture retention is required, and manage the entire printing environment. There is a problem that it is necessary to take a dry prevention measure considering that the ink is easy to dry, such as being installed on a window receiving sunlight or resuming use after a long period of non-use.
There is also a problem that it is insufficient to prevent drying from the nozzle surface of the long head and the entire head.

  The present invention has been made in view of the above-described problems, and in a fluid ejecting apparatus, not only the nozzle but also the fluid circulation portion is maintained at an appropriate humidity to suppress drying, and the fluid ejection characteristics are maintained in an optimum state. An object of the present invention is to provide a fluid ejecting apparatus that can perform the above-described operation. Another object of the present invention is to provide a fluid ejecting apparatus that can suppress evaporation of moisture from the fluid ejecting apparatus easily and inexpensively.

  In order to achieve the above object, the present invention provides a fluid ejecting apparatus that ejects a fluid from a fluid ejecting head having a plurality of nozzles, and that moisturizes covering a part or all of the outer surface of a fluid circulation portion that stores or circulates the fluid. It comprises a part.

  According to the present invention having such a feature, the ejection head having the nozzle forming surface and the moisturizing portion disposed in the vicinity of the fluid circulation location for storing or circulating the fluid in the vicinity thereof increase the humidity in the vicinity thereof. By preventing the nozzle row and the like from being dried while maintaining the fluid ejection characteristics, the fluid ejection characteristics can be maintained in an optimum state. Further, by providing the moisturizing portion over the necessary range even for the long head, it is possible to obtain the effect of preventing drying from the wide nozzle forming surface and the head. In addition, since the moisturizing unit can be provided with a simple configuration, it is possible to easily and easily suppress moisture evaporation of the fluid ejecting apparatus.

  In the present invention, the fluid circulation location may be at least one of the fluid ejecting head, a fluid supply system that supplies the fluid to the fluid ejecting head, and a maintenance system that sucks and discharges the fluid from the plurality of nozzles. By adopting a configuration including one, it is possible to suppress moisture from evaporating from the fluid ejecting apparatus easily and inexpensively in the fluid circulation portion, that is, the entire ink circulation path.

  Further, in the present invention, the moisturizing part includes a covering part that covers at least a part of the fluid circulation part, and a moisturizing agent filled in a space formed between the covering part and the fluid circulation part. By adopting the configuration provided, the moisturizing agent filled in the covering portion can be in direct contact with the outside of the fluid circulation portion to exhibit the moisturizing function and unnecessarily dry the moisture of the moisturizing agent. Therefore, it is possible to fix the moisturizing ability sustainably over a long period of time.

  Further, in the present invention, by adopting an aqueous solution containing glycerin as the moisturizing agent, it is possible to make use of the water retention of glycerin based on strong hygroscopicity and to continuously exhibit the moisturizing ability over a long period of time. .

  Further, in the present invention, by adopting the gel-like moisturizing agent, it is possible to indwell effectively without being washed away from the fluid circulation location.

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

FIG. 1 is a partially exploded view showing a schematic configuration of a main part of a printer (fluid ejecting apparatus) 1 according to an embodiment of the present invention.
The printer 1 is generally composed of a carriage 4 on which a sub tank (fluid circulation location) 2 and a recording head (fluid ejection head, fluid circulation location) 3 are mounted, and a printer main body 5.
The printer body 5 includes a carriage moving mechanism 65 that reciprocates the carriage 4, a paper feed mechanism (not shown) that conveys recording paper (not shown), and each nozzle 47 (see FIGS. 2 and 4) of the recording head 3. A capping mechanism 14 used for a cleaning operation for sucking the thickened ink (fluid) L, and an ink cartridge 6 for storing the ink L to be supplied to the recording head 3 are provided.

The carriage moving mechanism 65 includes a guide shaft 8 installed in the width direction of the printer body 5, a pulse motor 9, a drive pulley 10 that is connected to a rotation shaft of the pulse motor 9 and is driven to rotate by the pulse motor 9, An idler pulley 11 provided on the opposite side of the width direction of the printer body 5 with respect to the drive pulley 10, and a timing belt 12 that is spanned between the drive pulley 10 and the idler pulley 11 and connected to the carriage 4. , Is composed of.
The carriage 4 is configured to reciprocate in the main scanning direction along the guide shaft 8 by driving the pulse motor 9.

  The paper feed mechanism is composed of a paper feed motor, a paper feed roller (not shown) that is rotationally driven by the paper feed motor, and the like, and the platen 13 is linked to the recording (printing / printing) operation of the recording paper. Sequentially send on top.

  FIG. 2 is a schematic diagram illustrating a configuration in which a fluid circulation portion is wrapped by containers (covering portions) 50, 54, 55 and a tube (covering portion) 53. The following description will be made with reference to FIGS. 1 and 2 and other drawings as appropriate. The fluid circulation part is a part where the ink L is stored or circulated, and the ink supply system (fluid supply system) 35 shown in FIG. 2, that is, the ink pack 52, the ink supply tube 34, the recording head 3, and the cap member. 15 and the discharge tube 127.

Further, the moisturizing parts 81 to 84 are constituted by the containers 50, 54, 55 or the tube 53 and the moisturizing agent G, and wrap around the fluid circulation portion to prevent drying thereof.
The moisturizing unit 81 covers the ink pack 52 with the container 50 and fills the space 66 between the container 50 and the ink pack 52 with the moisturizing agent G.
The moisturizing unit 82 covers the ink supply tube 34 with the tube 53 and fills a space 67 between the tube 53 and the ink supply tube 34 with the moisturizing agent G.
The moisturizing unit 83 covers the recording head 3 with a container 54 and fills a space 68 between the container 54 and the recording head 3 with a moisturizing agent G.
The moisturizing unit 84 covers the cap member 15 with the container 55 and fills the space 69 between the container 55 and the cap member 15 with the moisturizing agent G.

  The capping mechanism 14 includes a cap member (fluid distribution portion) 15, a suction pump 16, and the like (see both FIG. 2 and FIG. 5). The cap member 15 is constituted by a member obtained by molding an elastic material such as rubber into a tray shape, and is disposed at the home position. This home position is set in an end area within the movement range of the carriage 4 and outside the recording area. When the power is turned off or when recording (fluid ejection processing) is not performed for a long time, the carriage is This is where 4 is located. The suction pump 16 is not limited to the tube pump type, and other types of pumps may be used.

When the carriage 4 is located at the home position, the cap member 15 contacts and seals the surface (that is, the nozzle forming surface 43a) of the nozzle substrate 43 (see FIG. 4) of the recording head 3. When the suction pump 16 is operated in this sealed state, the inside (sealed empty portion) S (see FIG. 2) of the cap member 15 is depressurized, and the ink L in the recording head 3 is forcibly discharged from the nozzle 47. Is done.
Further, the cap member 15 is used in a flushing process for ejecting ink droplets D (see FIGS. 4 and 5) to discharge the thickened ink L, bubbles, etc. before or during the recording operation by the recording head 3. Ink droplet D is received.

  Note that most of the recording head 3 other than the nozzle forming surface 43a exposed is accommodated in a container 54, and a space 68 formed between the inside of the container 54 and the outside of the recording head 3 that is a fluid circulation portion. (See FIG. 2 and FIG. 3) glycerin or a glycerin aqueous solution is filled as a humectant G. Similarly, the ink cartridge 6 is also housed in the container 50, and the moisturizing agent G is placed in a space 66 (see FIGS. 2 and 3) formed between the inside of the container 50 and the outside of the ink cartridge 6 that is a fluid circulation portion. Filled.

  Moreover, as a content component of the humectant G, not only glycerin but also a well-known gel (= gel) such as a refrigeration agent may be used. In addition, a gel (gel) is one in which a three-dimensional network structure formed by a polymer or the like takes in solvent molecules and loses fluidity as a whole. By the way, jelly is a kind of gel. Glycerin has almost no toxicity, is easily soluble in water, and has a strong hygroscopic property. Therefore, the glycerin is used for the moisturizing agent G in the present invention, taking advantage of its property of containing a lot of water and maintaining the moisturizing ability over a long period of time. It has been.

  In addition, an ink supply tube (fluid distribution portion) 34 that supplies ink L from the ink cartridge 6 to the recording head 3 is covered with a tube 53, and the inside of the tube 53 and the outside of the ink supply tube 34 that is a fluid distribution portion. A moisturizing agent G is filled in a space 67 (see FIGS. 2 and 6) formed between the two.

FIG. 3 is a cross-sectional view of the recording head 3, and FIG.
As shown in the two-dot broken line in FIG. 2 or FIGS. 3 and 4, the recording head 3 is accommodated in a container 54, and a humectant is formed in a space 68 formed between the inside of the container 54 and the outside of the recording head 3. G is filled. The humectant G may be water, but in this case, the submerged head 3 is not damaged and is configured so as not to hinder the operation. That is, the nozzle forming surface 43a is exposed to the outside of the container 54 while maintaining liquid tightness on the bottom surface of the container 54 (see FIGS. 3 to 5).
2, the cap member 15 is accommodated in the container 55, and the space 69 formed between the inside of the container 55 and the outside of the cap member 15 is filled with the moisturizing agent G. Yes.

  In addition, as shown with the broken line of FIG. 2, the external shape of the containers 50, 54, 55 and the tube 53 is an external shape for convenience of explaining the concept, and the shape is not limited. For the containers 50, 54, and 55, instead of the container filled with the moisturizing agent G, the moisturizing agent G is applied to the lower layer of the non-woven fabric in order to form the moistening layer, that is, the surface layer of the fluid circulation portion. It may be replaced with an attached one. Further, the tube 53 may be a tube filled with a humectant G between the double tubes. In any case, the shape is not limited.

Here, the configuration of the recording head 3 will be described in detail mainly with reference to FIG.
The recording head 3 includes an introduction needle unit 17, a head case 18, a flow path unit 19, and an actuator unit 20 as main components.
Two ink introduction needles 22 are mounted side by side on the upper surface of the introduction needle unit 17 with the filter 21 interposed. The sub tanks 2 are respectively attached to these ink introduction needles 22. An ink introduction path 23 corresponding to each ink introduction needle 22 is formed inside the introduction needle unit 17.
The upper end of the ink introduction path 23 communicates with the ink introduction needle 22 via the filter 21, and the lower end communicates with the case flow path 25 formed inside the head case 18 via the packing 24.
In this embodiment, since two types of ink are used, two subtanks 2 are provided. However, the present invention is naturally applicable to a configuration using three or more types of ink. Is.

The sub tank (fluid distribution part) 2 is molded from a resin material such as polypropylene. The sub-tank 2 is formed with a recess that becomes the ink chamber 27, and the ink chamber 27 is partitioned by attaching a transparent elastic sheet 26 to the opening surface of the recess.
In addition, a needle connection portion 28 into which the ink introduction needle 22 is inserted projects downward from the lower portion of the sub tank 2. The ink chamber 27 in the sub-tank 2 has a shallow mortar shape, and an opening on the upstream side of the connection channel 29 communicating with the needle connection portion 28 is located slightly below the vertical center on the side surface. The tank part filter 30 which filters the ink L is attached to this upstream side opening.
A seal member 31 into which the ink introduction needle 22 is liquid-tightly fitted is fitted in the internal space of the needle connection portion 28. As shown in FIG. 2, the sub-tank 2 is formed with an extending portion 32 having a communicating groove portion 32 ′ communicating with the ink chamber 27, and an ink inlet 33 projects from the upper surface of the extending portion 32. It is installed.

An ink supply tube 34 that supplies ink L stored in the ink cartridge 6 is connected to the ink inlet 33. Accordingly, the ink L that has passed through the ink supply tube 34 flows into the ink chamber 27 from the ink inlet 33 through the communication groove 32 ′.
The elastic sheet 26 can be deformed in a direction in which the ink chamber 27 contracts and a direction in which the ink chamber 27 expands. The pressure variation of the ink L is absorbed by the damper function due to the deformation of the elastic sheet 26. That is, the sub tank 2 functions as a pressure damper by the action of the elastic sheet 26. Therefore, the ink L is supplied to the recording head 3 side in a state where pressure fluctuation is absorbed in the sub tank 2.

The head case 18 is a synthetic resin hollow box-like member. The flow path unit 19 is joined to the lower end surface of the head case 18, and the actuator unit 20 is accommodated in the accommodating space 37 formed therein. The introduction needle unit 17 is attached in a state where the packing 24 is interposed on the upper end surface opposite to the side.
A case channel 25 is provided inside the head case 18 so as to penetrate the height direction. The upper end of the case flow path 25 communicates with the ink introduction path 23 of the introduction needle unit 17 via the packing 24.
Further, the lower end of the case channel 25 communicates with the common ink chamber 44 in the channel unit 19. Therefore, the ink L introduced from the ink introduction needle 22 is supplied to the common ink chamber 44 (see FIG. 4) side through the ink introduction path 23 and the case flow path 25.

Here, the configuration of the recording head 3 will be described in detail with reference mainly to FIG. 4 with reference to other drawings as appropriate.
The actuator unit 20 housed in the housing space 37 of the head case 18 includes a plurality of piezoelectric vibrators 38 arranged in a comb shape, a fixing plate 39 to which the piezoelectric vibrators 38 are joined, and a printer body. And a flexible cable 40 as a wiring member for supplying a drive signal from the side to the piezoelectric vibrator 38. Each piezoelectric vibrator 38 has a fixed end portion bonded to the fixed plate 39 and a free end portion protruding outward from the tip surface of the fixed plate 39. That is, each piezoelectric vibrator 38 is mounted on the fixed plate 39 in a so-called cantilever state.
The fixing plate 39 that supports each piezoelectric vibrator 38 is made of stainless steel having a thickness of about 1 mm, for example. The actuator unit 20 is housed and fixed in the housing space 37 by bonding the back surface of the fixed plate 39 to the inner wall surface of the case that defines the housing space 37.

  In the embodiment of the present invention, any driving principle of fluid ejection may be used, but as an embodiment of the recording head 3, a piezoelectric element (laminated) type is illustrated. Further, as the piezoelectric element 38, a type other than the laminated type (for example, monomorph, unimorph, bimorph, Mooney type, multi-Mooney type, cymbal type, etc.) may be used. Furthermore, without being limited to the piezo jet type using the piezoelectric element 38, for example, a thermal method can be adopted. Thus, any driving principle of injection may be used.

The flow path unit 19 is bonded so that the flow path unit constituting members including the vibration plate (sealing plate) 41, the flow path substrate 42, and the nozzle substrate 43 are laminated and integrated. The flow path unit 19 is a member that forms a series of ink flow paths from the common ink chamber 44 to the nozzle 47 through the ink supply port 45 and the pressure chamber 46. The pressure chamber 46 is formed as an elongated chamber in a direction perpendicular to the direction in which the nozzles 47 are arranged (nozzle row direction).
The common ink chamber 44 communicates with the case flow path 25 and is a chamber into which ink L is introduced from the ink introduction needle 22 (see FIG. 3) side.
The ink L introduced into the common ink chamber 44 is distributed and supplied to the pressure chambers 46 through the ink supply ports 45.

The nozzle substrate 43 disposed at the bottom of the flow path unit 19 is a metal thin plate material in which a plurality of nozzles 47 are opened in a row at a pitch (for example, 180 dpi) corresponding to the dot formation density. The nozzle substrate 43 of the present embodiment is made of a stainless steel plate, and in this embodiment, a total of 22 rows of nozzles 47 (that is, nozzle rows) are arranged in parallel corresponding to each sub tank 2. One nozzle row is composed of 180 nozzles 47, for example.
The flow path substrate 42 disposed between the nozzle substrate 43 and the vibration plate 41 includes a flow path portion serving as an ink flow path, specifically, a common ink chamber 44, an ink supply port 45, and a pressure chamber 46. It is the plate-shaped member by which the empty part which becomes is formed.

  Further, the flow path substrate 42 is produced by subjecting a silicon wafer, which is a crystalline base material, to anisotropic etching. The vibration plate 41 is a double-structured composite plate material in which an elastic film is laminated on a metal support plate such as stainless steel. The part corresponding to the pressure chamber 46 of the vibration plate 41 is formed with an island portion 48 to which the tip surface of the piezoelectric vibrator 38 is joined by removing the support plate in an annular shape by etching or the like. Functions as a diaphragm. That is, the diaphragm 41 is configured such that the elastic film around the island portion 48 is elastically deformed in accordance with the operation of the piezoelectric vibrator 38. The vibration plate 41 also seals one opening surface of the flow path substrate 42 and functions as a compliance portion 49. As for the portion corresponding to the compliance portion 49, the support plate is removed by etching or the like in the same manner as the diaphragm portion to make only the elastic film.

  In the recording head 3, when a drive signal is supplied to the piezoelectric vibrator 38 through the flexible cable 40, the piezoelectric vibrator 38 expands and contracts in the longitudinal direction of the element, and accordingly, the island portion 48 enters the pressure chamber 46. Move in the direction of approaching or separating. As a result, the volume of the pressure chamber 46 changes, and the pressure fluctuation occurs in the ink L in the pressure chamber 46. The ink droplet D is ejected from the nozzle 47 by this pressure fluctuation.

As shown in FIG. 2, the ink cartridge 6 includes an ink pack (fluid distribution portion) 52 formed in a hollow box shape with a plastic material, and a container 50 that accommodates the ink pack 52. The ink cartridge 6 communicates with one end of the ink supply tube 34 and is configured to supply the ink L in the ink pack 52 to the recording head 3 side due to a water head difference from the nozzle forming surface 43a of the recording head 3. Has been. Specifically, the relative positional relationship between the ink cartridge 6 and the recording head 3 in the gravitational direction is set so that a slight negative pressure is applied to the meniscus of the nozzle 47.
Then, the ink L is supplied to the pressure chamber 46 and the ink L in the pressure chamber 46 is discharged by a pressure change caused by driving the piezoelectric vibrator 38.

  The cap member 15 is a tray-like member having an open upper surface, and is made of an elastic member such as an elastomer. An ink absorber 77 is disposed inside the cap member 15. The ink absorber 77 has a high holding power of the ink L, and is made of a nonwoven fabric such as felt, for example.

FIG. 5 is a view showing the configuration of the suction pump 16 connected to the cap member 15.
On the bottom wall of the cap member 15, a discharge portion 126 for discharging the ink L accumulated in the cap member 15 protrudes downward, and a discharge passage 126 a is formed in the discharge portion 126. One end portion of a discharge tube (fluid distribution portion) 127 made of a flexible material or the like is connected to the discharge portion 126, and the other end portion of the discharge tube 127 is inserted into the waste ink tank 128.

  The waste ink tank 128 contains a waste ink absorber 129 made of a porous member, and the ink L collected by the waste ink absorber 129 is absorbed. The waste ink tank 128 is disposed below the platen 13 (see FIG. 1). A tube pump type suction pump 16 is disposed between the cap member 15 and the waste ink tank 128.

Then, when the pump wheel 132 is rotated in the forward direction (arrow direction), the inside of the discharge tube 127 upstream from the tube pump 123 is decompressed.
Thus, the ink L accumulated in the cap member 15 is gradually discharged toward the waste ink tank 128 by the forward rotation of the pump wheel 132.

Next, the moisturizing action of the tube 53 that covers the fluid circulation location or the containers 50, 54, and 55 that accommodate the fluid circulation location will be described in detail with reference to FIG.
FIG. 6 is an explanatory diagram of bubbles B generated in the ink supply tube 34 provided in the printer 1 according to the embodiment of the present invention.
The ink supply tube 34 that supplies the ink L from the ink cartridge 6 to the recording head 3 is covered with a tube 53 and formed between the inside of the tube 53 and the outside of the ink supply tube 34 that is a fluid circulation portion. The moisturizing agent G is filled in the space 67 (see also FIG. 2).

  The ink supply tube 34 shown in FIG. 6 is a fluid circulation portion having a fluid flow path through which the ink L flows. If the outer surface of the ink supply tube 34 is exposed to the outside air A without any countermeasures, the moisture of the ink L is exposed to the ink supply tube 34. It evaporates little by little while passing through the tube wall. The reason for the evaporation is that the barrier property for blocking the air permeability is incomplete due to the property of the resin material forming the tube wall.

  In the present invention, a humectant G is filled in a coating 53 that covers a part or all of the outer surface of the tube wall of the ink supply tube 34 and a space 67 between the outer surfaces. Therefore, the gas exchange indicated by the arrow is reduced by reducing the difference between the saturated water vapor pressure of the bubbles B contained in the ink L and the saturated water vapor pressure of the air in the vicinity of the moisturizing agent G surrounding the ink supply tube 34. Is suppressed, and even if only moisture is about to evaporate from the bubble B, the expansion growth of the bubble B is suppressed.

However, when moisture retention measures are not taken at the fluid circulation location, the air bubbles (N ₂ and O ₂ ) are taken in from the outside air A so that the bubbles B in the ink supply tube 34 are replaced with moisture that has evaporated and decreased therefrom. The problem of drying out by expanding and growing is inevitable.
The above-described action of suppressing the expansion of bubbles B is classified into air components existing inside and outside the ink flow path, that is, water vapor (H ₂ O) and air (N ₂ and O ₂ ). From the viewpoint of pressure, the conditions (a) for the outside air A and the conditions (b) for the bubbles B will be described below.

Condition (a) Outside air 25 degrees 40% → Water vapor partial pressure is 1.9 Kpa, air partial pressure is 99.4 Kpa
Condition (b) Bubble 25% 100% → Water vapor partial pressure is 3.2 Kpa, air partial pressure is 98.1 Kpa
The action of the bubble B component to be the same as the outside air A component, that is, the condition (b) approaches the condition (a), so that the water vapor partial pressure decreases from 3.2 Kpa to 1.9 Kpa. While the water evaporates toward the outside air, the air partial pressure of the bubble B increases from 98.1 Kpa to 99.4 Kpa. As a result, only the dry air (N ₂ and O ₂ ) components from the outside air are taken into the bubble B. That is, the bubble B expands and grows by gas exchange.
That is, if the relative humidity of the environment in which the printer 1 is installed is low and the water vapor partial pressure of the outside air A is low, the bubble B in the ink flow path expands and grows, causing a problem of drying.

  Therefore, in the present invention, measures are taken so as to reduce the difference between the saturated water vapor pressure of the bubbles B and the saturated water vapor pressure of the outside air A contained in the ink L that is the object of moisture retention at the fluid circulation location. That is, the outside air A and the inside of the ink flow path are blocked by the moisturizing agent G surrounding the outside of the ink flow path, and a simulated environment with a humidity of 100% is set outside the ink flow path, thereby satisfying the condition (a). If the difference in the numerical values of the water vapor partial pressure and the air partial pressure shown in the condition (b) is eliminated, it is possible to prevent drying in the ink flow path.

Further, from the viewpoint of suppressing not only moisture H ₂ O but also gas exchange, it is possible to eliminate the adverse effects of drying by suppressing gas exchange of nitrogen N ₂ and oxygen O ₂ which are the main components of air. is there. Further, from the viewpoint of eliminating the drop in the saturated water vapor pressure, if the saturated water vapor pressure of the outside air A and the saturated water vapor pressure of the bubbles B in the ink L are brought close to each other so that there is no drop in the saturated water vapor pressure between them, Since it becomes difficult for the gas exchange action to try to evaporate only the moisture from the bubbles B, the drying of the moisture retaining object accompanying the expansion and growth of the bubbles B is suppressed. The moisturizing effect by such an action is not only the inside of the ink supply system (fluid supply system, fluid distribution location) 35 and the recording head 3, but also the maintenance system 130, that is, the discharge that discharges the ink L remaining on the nozzle formation surface 43a. It can also be applied to prevent the tube 127 from drying.

The ink L in the recording head 3 is a case where the printer 1 has been left for a long period of time because moisture evaporation due to gas exchange with the outside air A outside the ink flow path is suppressed. However, it is possible to avoid ejection failure due to ink thickening.
Further, the printer 1 of the present invention is suitable for a consumer device because a simple and inexpensive configuration is sufficient as compared with the humidity management for the entire environment of the head supply system.
In addition, according to the present invention, since the moisturizing agent G is disposed outside the ink flow path, it is possible to easily suppress evaporation of moisture at a low cost, and a wide and long head in a long line head. It is also suitable as a moisturizing measure for the supply system.

  The preferred embodiments according to the present invention have been described above with reference to the accompanying drawings. However, it goes without saying that the present invention is not limited to such examples, and the embodiments described above may be combined. It is obvious for those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims. It is understood that it belongs to.

In the above-described embodiment, the fluid ejecting apparatus is embodied as an ink jet printer (recording apparatus). However, the fluid ejecting apparatus is not limited to this, and other fluids other than ink (a liquid material in which particles of a functional material are dispersed, a gel) Such a fluid body) can be embodied in a fluid ejecting apparatus that ejects or ejects the fluid.
For example, a liquid material injection device for injecting a liquid material in the form of dispersed or dissolved materials such as electrode materials and color materials used in the manufacture of liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays, and biochip manufacturing It may be a fluid ejecting apparatus that ejects a bio-organic substance used in the above, or a fluid ejecting apparatus that ejects a fluid that is used as a precision pipette and serves as a sample.

In addition, transparent resin liquids such as UV curable resins to form fluid injection devices that inject lubricating oil onto precision machines such as watches and cameras, micro hemispherical lenses (optical lenses) used in optical communication elements, etc. May be a fluid ejecting apparatus that ejects a liquid onto the substrate, a fluid ejecting apparatus that ejects an etching solution such as acid or alkali to etch the substrate, or a fluid ejecting apparatus that ejects gel.
In any one of these fluid ejecting apparatuses, the present invention can be applied if there is a possibility that the ejected fluid (liquid or fluid) may be thickened by drying or the like.

1 is a partially exploded view showing a schematic configuration of a main part of a printer according to an embodiment of the present invention. It is a schematic diagram explaining the structure which wrapped the fluid distribution location with the container and coating | coated part with which the printer which concerns on embodiment of this invention is equipped. FIG. 2 is a cross-sectional view of a recording head provided in the printer according to the embodiment of the invention. FIG. 3 is a cross-sectional view of a main part of a recording head provided in the printer according to the embodiment of the invention. It is sectional drawing of the suction pump connected with the cap member with which the printer which concerns on embodiment of this invention is provided. It is explanatory drawing of the bubble which generate | occur | produces in the ink supply tube with which the printer which concerns on embodiment of this invention is provided.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Printer (fluid ejecting apparatus), 2 ... Sub tank (fluid distribution | circulation location) 3 ... Recording head (fluid ejection head, fluid distribution location), 15 ... Cap member (fluid receiving part), 34 ... Ink supply tube, 34 ... Ink Supply tube (fluid distribution location), 35 ... Ink supply system (fluid supply system, fluid distribution location), 47 ... Nozzle, 52 ... Ink pack (fluid distribution location), 53 ... Tube (cover), 50, 54, 55 ... Container, 66-69 ... Space, 81-84 ... Moisturizing part, 127 ... Discharge tube (fluid distribution part), 130 ... Maintenance system, B ... Foam, G ... Moisturizing agent, L ... Ink (fluid)

Claims (5)

In a fluid ejecting apparatus that ejects fluid from a fluid ejecting head having a plurality of nozzles,
A fluid ejecting apparatus comprising: a moisturizing unit that covers a part or all of an outer surface of a fluid circulation portion that stores or circulates the fluid.   The fluid circulation location includes at least one of the fluid ejection head, a fluid supply system that supplies the fluid to the fluid ejection head, and a maintenance system that sucks and discharges the fluid from the plurality of nozzles. The fluid ejecting apparatus according to claim 1, wherein: The moisturizing part is a covering part that covers at least a part of the fluid circulation part;
A humectant filled in a space formed between the covering portion and the fluid circulation portion;
The fluid ejecting apparatus according to claim 1, further comprising:   The fluid ejecting apparatus according to claim 3, wherein the humectant is an aqueous solution containing glycerin.   The fluid ejecting apparatus according to claim 3, wherein the humectant is in a gel form.

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