JP2005125653A - Inkjet head, inkjet recorder, and device and method of cleaning inkjet head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet head in which foreign matter clogging a nozzle hole, an ink channel or a liquid resistance section can be readily removed, a cleaning device for removing a foreign material existing in the inkjet head, and a cleaning method therefor. <P>SOLUTION: This inkjet head 44 comprises a plurality of liquid chambers 3 each having the liquid resistance section 4, the nozzle hole 6, a diaphragm 7, piezoelectric elements 9 corresponding to the liquid chambers 3, and a frame member 10 having a common ink channel 11. As a filter is not provided on the position of the channel and the cross section area of the nozzle hole 6 is the minimum in the whole channel having ink flowing therein in the inkjet head 44, it is possible to readily remove the foreign matter from the inner section of the inkjet head by injecting a cleaning liquid from a side of a nozzle face by using a cleaning liquid injecting device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an ink jet head, an ink jet recording apparatus, an ink jet head cleaning apparatus, and a cleaning method. More specifically, it is not necessary to equip a flow path through which ink flows in an ink jet head with a filter for capturing foreign matter. The present invention relates to an inkjet head, an inkjet recording apparatus, an inkjet head cleaning apparatus and a cleaning method for cleaning them.

In general, in an ink jet recording apparatus, an ink jet head is configured by joining a plurality of members with an adhesive. In particular, the diaphragm having the ink flow path, the flow path plate, the nozzle plate, and the frame having the common liquid chamber are joined in a clean room so as to suppress the entry of foreign matter into the ink flow path as much as possible. However, it cannot be said that foreign matter does not enter the ink jet head before the flow path is formed in manufacturing. Further, since foreign matters may adhere to each member, it is inevitable that foreign matters may exist in the assembled inkjet head.
Therefore, it is necessary to clean the assembled ink jet head and remove foreign substances present therein, and therefore various cleaning apparatuses and cleaning methods as described below have been proposed.

The cleaning device and cleaning method for an inkjet head described in Patent Document 1 is a cleaning method after processing a piezoelectric element, and is a cleaning method in a groove having a high aspect ratio.
In the inkjet head dust removal method described in Patent Document 2, a plurality of rows of ink discharge communication paths are provided, and dust and foreign matter are removed from the discharge port.
The cleaning apparatus and cleaning method for an inkjet recording apparatus described in Patent Document 3 are provided with a cleaning liquid discharge port that can be sealed in an ink flow path of an inkjet head, and a cleaning liquid suction unit is connected to the cleaning liquid discharge port to suck and discharge the cleaning liquid. To do.
In the method for cleaning an ink jet head described in Patent Document 4, the nozzle surface of the ink jet head is immersed in an ultrasonic cleaning tank, and cleaning is performed by sucking a cleaning liquid in the cleaning tank to remove foreign matters.
In the inkjet head cleaning method and apparatus described in Patent Document 5, a nozzle that injects a cleaning liquid at a high pressure is directly opposed to a nozzle hole to remove foreign matter in the individual liquid chamber.
JP 2000-229271 A JP 2002-205393 A JP-A-06-008471 Japanese Patent Application Laid-Open No. 09-254397 Japanese Patent Laid-Open No. 11-334091

Ink jet heads used in recent ink jet recording apparatuses are being developed to increase the number of nozzles and increase the definition in order to form finer ink droplets, and the nozzle holes are miniaturized. For this reason, it has become apparent that foreign matter in the ink jet head clogs the nozzle holes and the fluid resistance portion, causing ink ejection failure.
According to the inventions described in Patent Documents 2 and 3, the cleaning liquid discharge port is provided in the ink jet head, and the cleaning liquid is sucked and discharged from the cleaning liquid discharge port. By providing the cleaning liquid discharge port, the cleaning liquid discharge port is sealed. It becomes necessary and causes an increase in manufacturing man-hours, and the mold becomes complicated and causes an increase in initial cost.
In addition, the inkjet head cleaning method described in Patent Document 4 removes foreign matter by immersing the nozzle surface of the inkjet head in an ultrasonic cleaning tank and sucking the cleaning liquid in the cleaning tank. It becomes a fluid resistance and the flow rate is increased so that the foreign matter cannot be efficiently removed.
As described in Patent Document 5, as a proposal for increasing the flow rate, there is a method in which a nozzle for injecting a cleaning liquid at a high pressure is directly opposed to a nozzle hole to remove foreign matters in the individual liquid chamber. Targeting becomes difficult due to miniaturization. Further, since the foreign matters are individually removed, the foreign matters in the vicinity of the central portion may move to the end portions.

  In view of the problems of the conventional example, the present invention proposes an ink jet head that can easily remove foreign matters clogged in the nozzle holes, the ink flow paths, and the fluid resistance portion, and such an ink jet head. It is an object of the present invention to propose an improved cleaning apparatus and cleaning method for removing foreign substances present in the interior.

According to the first aspect of the present invention, the foreign matter remains in the ink jet head by minimizing the cross-sectional area of the nozzle hole in each flow path of the ink flowing through the ink jet head and eliminating the need to mount a filter. It is an object of the present invention to provide an ink jet head that is configured so that the flow path through which ink flows can be easily cleaned and the shape of the ink supply section is not restricted.
A second object of the present invention is to make it difficult for foreign matter to be caught at the corners by forming the corners of the wall surface forming the fluid resistance portion by a curved surface.

  According to the invention of claim 3, by forming an ink jet recording apparatus using the ink jet head of claim 1 or 2, it is easy to remove foreign matter from the inside of the ink jet head, and both high image quality and reliability are achieved. An object is to obtain an ink jet recording apparatus.

According to a fourth aspect of the present invention, there is provided an ink jet head cleaning apparatus which is used in the ink jet head according to the first or second aspect and injects a cleaning liquid into the ink jet head to easily and surely remove foreign substances present in the ink jet head. For the purpose.
A fifth aspect of the present invention is to provide an ink jet head cleaning apparatus according to the fourth aspect of the present invention, which reliably removes foreign matter by increasing the injection pressure of the cleaning liquid injected from the nozzle surface. .
According to a sixth aspect of the present invention, in the ink jet head cleaning device according to the fourth or fifth aspect, in addition to the cleaning liquid injection from the nozzle surface, the cleaning liquid is sucked from the ink supply part side of the ink jet head to generate pulsation in the cleaning liquid to remove foreign matter. An object of the present invention is to provide an inkjet head cleaning device for removal.
According to a seventh aspect of the present invention, there is provided an ink jet head cleaning apparatus according to any one of the fourth to sixth aspects, wherein the foreign matter caught on the fluid resistance portion is removed to remove the foreign matter by applying pressure from the ink supply portion side. For the purpose.

According to an eighth aspect of the present invention, there is provided an ink jet head cleaning method using the ink jet head cleaning device according to any one of the fourth to seventh aspects of the present invention to improve the wettability with the inner wall of the ink flow path and increase the permeability and remove foreign matters with a liquid suitable for cleaning. The purpose is to provide.
A ninth aspect of the present invention is to provide an ink jet head cleaning method according to the eighth aspect of the present invention, wherein foreign matter is removed by mixing air with a cleaning liquid to generate bubbles.

According to a first aspect of the present invention, there is provided an inkjet head having a plurality of pressurized liquid chambers having a fluid resistance portion, a nozzle communicating with the pressurized liquid chamber, and a pressure generating element corresponding to the pressurized liquid chamber. The cross-sectional area of the nozzle is minimum in the flow path through which the ink flows, and no filter is provided in the flow path.
According to a second aspect of the present invention, in the ink jet head according to the first aspect, corners of the wall surface forming the fluid resistance portion are formed in a curved surface.

  According to a third aspect of the present invention, there is provided an ink jet recording apparatus for forming an image on a recording medium by ejecting ink droplets from a nozzle by driving energy generated by a pressure generating element corresponding to a pressurized liquid chamber. At least one of the ink jet heads described above is provided.

According to a fourth aspect of the present invention, in the inkjet head cleaning apparatus for removing foreign matter from the inkjet head according to the first or second aspect, a cleaning liquid is injected from a nozzle surface side in the inkjet head by a cleaning liquid injection apparatus, and the nozzle and The pressurized liquid chamber is washed.
According to a fifth aspect of the present invention, in the inkjet head cleaning apparatus according to the fourth aspect, the cleaning liquid injection pressure of the cleaning liquid injection apparatus is 0.1 to 0.5 Mpa.
According to a sixth aspect of the present invention, in the ink jet head cleaning device according to the fourth or fifth aspect, a vacuum suction device for sucking a cleaning liquid from an ink supply unit of the ink jet head is added.
According to a seventh aspect of the present invention, in the ink jet head cleaning apparatus according to any one of the fourth to sixth aspects, the cleaning liquid is caused to flow backward from the ink supply portion of the ink jet head in order to remove the foreign matter caught on the fluid resistance portion of the ink jet head. It is characterized by.

According to an eighth aspect of the present invention, in the inkjet head cleaning method using the inkjet head cleaning device according to any one of the fourth to seventh aspects, the cleaning liquid includes a surfactant and a penetrating agent.
According to a ninth aspect of the present invention, in the ink jet head cleaning method according to the eighth aspect of the invention, bubbles are generated by sucking air after the cleaning liquid is injected, and foreign matters attached to the wall surface in the flow path through which the ink flows are removed. Features.

According to the first aspect of the present invention, since the cross-sectional area of the nozzle hole is the smallest in the flow path for the ink in the ink jet head, it is not necessary to mount a filter for capturing foreign matter in the ink flow path. The path can be easily cleaned, the foreign matter can be easily discharged, and the shape of the ink supply unit can be formed without any filter restriction.
According to the second aspect of the invention, the corner of the wall surface forming the fluid resistance portion is formed by a curved surface such as an arc, so that foreign matter can be prevented from being caught by the fluid resistance portion.

  The invention of claim 3 is a recording apparatus comprising at least one ink jet head according to claim 1 or 2, whereby it is easy to remove foreign matter from the inside of the ink jet head, and high image quality and reliability. Can be provided.

The invention according to claim 4 can provide an ink jet head cleaning device that easily removes foreign matter by injecting the cleaning liquid into the ink jet head from the nozzle hole side by the cleaning liquid injection device.
The invention of claim 5 can provide an ink jet head cleaning device that improves the foreign matter removal effect by increasing the cleaning liquid injection pressure.
The invention according to claim 6 provides an inkjet head cleaning device that not only injects cleaning liquid from the nozzle surface but also generates pulsation in the ink supply path by suctioning the cleaning liquid from the ink supply unit, thereby reliably removing foreign matter. can do.
The seventh aspect of the invention can provide an ink jet head cleaning device that reliably removes foreign matter caught on the fluid resistance portion by returning the cleaning liquid from the ink supply portion.

The invention according to claim 8 provides an ink jet head cleaning method that facilitates intrusion of the cleaning liquid from the nozzle and removes viscous foreign substances by using a cleaning liquid containing a surfactant and a penetrant. it can.
The invention of claim 9 provides an ink jet head cleaning method that reliably removes foreign matter present in a pressurized liquid chamber, a common liquid chamber, and an ink supply section by generating bubbles using a cleaning liquid and air. it can.

  The present invention proposes an ink jet head that can easily remove foreign substances clogged in nozzle holes and fluid resistance parts, and further provides an improved cleaning apparatus and cleaning method for removing foreign substances present in such an ink jet head. An inkjet head having a plurality of pressurized liquid chambers having a fluid resistance portion, a nozzle communicating with the pressurized liquid chamber, and a pressure generating element corresponding to the pressurized liquid chamber. The cross-sectional area of the nozzle is minimized in the flow path through which the ink flows, and no filter is provided in the flow path. Further, the inkjet head cleaning device is characterized in that the cleaning liquid is injected from the flow path through which the ink flows from the nozzle surface side of the inkjet head by the cleaning liquid injection device, and the nozzle and the pressurized liquid chamber are cleaned to remove foreign matters. And

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 8 is a perspective view showing a main configuration of an ink jet recording apparatus to which the ink jet head of the present invention is applied, and FIG. 9 is a side sectional view of the same configuration.
The ink jet recording apparatus of the present invention includes a carriage 43 movable in the main scanning direction inside the recording apparatus main body 31, a recording head including an ink jet head 44 mounted on the carriage 43, an ink cartridge 45 for supplying ink to the recording head, and the like. A printing mechanism portion 32 configured is housed, and a paper feed cassette (or a paper feed tray) 34 on which a large number of sheets 33 can be stacked from the front side is detachably attached to the lower portion of the recording apparatus main body 31. In addition, the manual feed tray 35 for manually feeding the paper 33 can be opened, the paper 33 fed from the paper feed cassette 34 or the manual feed tray 35 is taken in, and the printing mechanism unit 32 takes it. After the image is recorded, it is discharged to a discharge tray 36 mounted on the rear side.

  The printing mechanism 32 holds the carriage 43 slidably in the main scanning direction (the direction perpendicular to the paper in FIG. 9) with a main guide rod 41 and a sub guide rod 42 which are guide members horizontally mounted on left and right side plates (not shown). The carriage 43 has a recording head composed of an inkjet head 44 for ejecting ink droplets of each color of yellow (Y), cyan (C), magenta (M), and black (Bk). And are mounted with the ink droplet ejection direction facing downward. The carriage 43 is mounted with replaceable ink cartridges 45 for supplying ink of each color to the recording head. The ink cartridge 45 has an air port that communicates with the atmosphere upward, a supply port that supplies ink to the inkjet head 44 below, and a porous body filled with ink inside, and a capillary tube for the porous body. The ink supplied to the inkjet head 44 is maintained at a slight negative pressure by force.

  Moreover, although the inkjet head 44 of each color is used here as the inkjet head 44, it may be a single inkjet head having nozzles that eject ink droplets of each color. Further, the ink jet head 44 used as a recording head is a piezoelectric type that pressurizes ink through a vibration plate that forms a liquid chamber wall surface by an electromechanical conversion element such as a piezoelectric element, or a bubble is generated by a heating resistor to generate ink. A bubble type that pressurizes, or an electrostatic type that pressurizes ink by displacing the diaphragm with an electrostatic force between the diaphragm that forms the wall surface of the ink flow path and the electrode facing it can be used. In this embodiment, a piezo ink jet head is used.

  Here, the carriage 43 is slidably fitted to the main guide rod 41 on the rear side (downstream side in the paper conveyance direction), and slidably mounted on the sub guide rod 42 on the front side (upstream side in the paper conveyance direction). doing. In order to move and scan the carriage 43 in the main scanning direction, a timing belt 50 is stretched between a driving pulley 48 and a driven pulley 49 that are rotationally driven by a main scanning motor 47, and the timing belt 50 is attached to the carriage 43. The carriage 43 is reciprocated by the forward and reverse rotations of the main scanning motor 47.

  On the other hand, in order to convey the paper 33 set in the paper feed cassette 34 to the lower side of the ink jet head 44, the paper feed roller 51 and the friction pad 52 for separating and feeding the paper 33 from the paper feed cassette 34 and the paper 33 are guided. A guide member 53 for conveying, a conveyance roller 54 for reversing and conveying the fed paper 33, a conveyance roller 55 pressed against the peripheral surface of the conveyance roller 54, and a feeding angle of the sheet 33 from the conveyance roller 54 are defined. A tip roller 56 is provided. The conveyance roller 54 is rotationally driven by a sub-scanning motor 57 via a gear train.

  A printing receiving member 59 is provided as a paper guide member that guides the paper 33 fed from the transport roller 54 below the ink jet head 44 in accordance with the range of movement of the carriage 43 in the main scanning direction. A conveyance roller 61 and a spur 62 that are rotationally driven to send out the paper 33 in the paper discharge direction are provided on the downstream side of the printing receiving member 59 in the paper conveyance direction, and paper discharge that further feeds the paper 33 to the paper discharge tray 36. A roller 63 and a spur 64 and guide members 65 and 66 that form a paper discharge path are disposed.

  During recording, the inkjet head 44 is driven in accordance with the image signal while moving the carriage 43, thereby ejecting ink onto the stopped paper 33 to record one line. Record the line. Upon receiving a recording end signal or a signal that the trailing edge of the paper 33 reaches the recording area, the recording operation is terminated and the paper 33 is discharged.

  Further, a recovery device 67 for recovering the ejection failure of the inkjet head 44 is disposed at a position outside the recording area on the right end side in the movement direction of the carriage 43. The recovery device 67 has a cap unit, a suction unit, and a cleaning unit. While waiting for printing, the carriage 43 is moved to the recovery device 67 side and the inkjet head 44 is capped by the capping means, and the nozzle opening is kept in a wet state to prevent ejection failure due to ink drying. Further, by ejecting ink that is not related to recording in the middle of recording or the like, the ink viscosity of all the nozzle openings is made constant and stable ejection performance is maintained.

  When a discharge failure occurs, the nozzle port of the inkjet head 44 is sealed with a capping unit, air bubbles are sucked out together with ink from the nozzle port with a suction unit through a tube, and ink or dust adhering to the nozzle surface is cleaned with a cleaning unit. And the defective discharge is recovered. Further, the sucked ink is discharged to a waste ink reservoir (not shown) installed at the lower part of the main body and absorbed and held by an ink absorber inside the waste ink reservoir.

The ink jet head of the present invention will be described.
FIG. 1 is a sectional view showing an ink jet head to which the present invention is applied, and FIG. 2 is an exploded perspective view showing the ink jet head shown in FIG.
The ink jet head 44 includes a flow path plate 1 formed of a silicon substrate or the like and formed with a plurality of communication holes 2 and individual liquid chambers 3 serving as ink flow paths, and Ni electroforming or the like on the upper surface of the flow path plate 1. The nozzle plate 5 having a plurality of nozzle holes 6 formed thereon is joined, and the diaphragm 7 formed by Ni electroforming or the like is joined to the lower surface of the flow path plate 1 to constitute a liquid chamber portion. A constricted portion is provided in the liquid chamber 3 of the flow path plate 1 as a fluid resistance portion 4. On the lower surface of the diaphragm 7, an actuator portion in which two rows of stacked piezoelectric elements 9 are provided on a base member 8 made of metal is joined. A frame member 10 having a common ink flow path 11 formed on both outer sides of the piezoelectric element 9 is joined to the diaphragm 7 to supply ink to each individual liquid chamber.

The ink jet head 44 configured as described above is displaced in the stacking direction of the piezoelectric elements 9 (vertical direction in FIG. 1) by applying a driving voltage to the piezoelectric elements 9, and the diaphragm 7 is moved to each individual liquid chamber side. Due to deformation and displacement, the volume of the liquid chamber 3 decreases, the pressure in the liquid chamber increases, and ink droplets are ejected from the nozzle holes 6 of the nozzle plate 5 through the communication holes 2.
Causes of ink ejection failure include foreign matter clogging in the nozzle holes 6 and foreign matter clogging in the fluid resistance portion 4.

3A and 3B are cross-sectional views showing the frame member cut along the ink flow path, FIG. 3A shows the frame member of the present invention, and FIG. 3B shows a conventional frame member.
As shown in FIG. 3A, the frame member 10 used in the inkjet head 44 of the present invention has a configuration in which no filter is provided in the ink supply port 12 of the common ink flow path 11. On the other hand, as shown in FIG. 3B, the frame member 10 used in the conventional inkjet head has a configuration in which a filter mounting portion 12a is formed in the ink supply port 12 of the ink flow path 11 and the filter is equipped. It is.
Thus, the ink jet head of the present invention can form the ink flow path 11 suitable for discharging foreign matter without limiting the shape of the ink supply port 12 of the ink flow path 11 to the size of the filter. In addition, since the inkjet head of the present invention is configured not to be equipped with a filter in the entire flow path of the inkjet head, the sectional area of the nozzle hole 6 formed in the nozzle plate 5 can be minimized in the entire flow path. Become.

FIG. 4 is a plan view showing a plurality of communication holes formed in the flow path plate and a liquid chamber serving as an ink flow path. FIG. 4A shows the communication holes and the liquid chamber of the present invention, and FIG. ) Shows a communication hole and a liquid chamber of a conventional example.
As for the entrance shape of the fluid resistance portion 4 of the liquid chamber 3 formed in the flow path plate used in the ink jet head of the conventional example, the corner portion of the wall surface is a square shape 4b as shown in FIG. 4B. Normally, the inlet shape of the fluid resistance portion 4 of the liquid chamber 3 formed in the flow path plate 1 used in the ink jet head 44 of the present invention is such that the corner portion which is the intersection of the wall surfaces is dropped. It is formed in the curved surface shape 4a like a shape.
By making the inlet shape of the fluid resistance portion 4 of the liquid chamber 3 a curved surface shape 4a such as an arc, the liquid flow is not hindered and the shape in which foreign matter is not easily caught can be obtained. Can be prevented.

FIG. 5 is a diagram illustrating a state in which a fan-shaped cap of the cleaning device is brought into close contact with the nozzle surface of the ink jet head and the cleaning liquid is injected into the nozzle hole.
As shown in FIG. 5, the ink supply port 12 of the frame member 10 is suitable for discharging foreign matter on which no filter mounting portion is formed in order to remove foreign matter that has entered the nozzle hole, liquid chamber, and fluid resistance portion of the inkjet head 44. The fan-shaped cap 23 of the cleaning device 21 is brought into close contact with the nozzle surface of the inkjet head 44, and the cleaning liquid is injected into the nozzle hole 6 by the injection pump 22 in this state.
When the pressure is uniformly applied from the nozzle surface of the inkjet head, the injection pressure of the cleaning liquid into each liquid chamber and the fluid resistance portion is preferably 0.1 to 0.5 Mpa.
If it is 0.1 Mpa or less, the foreign matter removing ability is low, and if it is 0.5 Mpa or more, the inkjet head may be destroyed.

FIG. 6 is a view showing a state in which the cleaning liquid filling into the inkjet head is improved by vacuum suction from the ink supply port side in addition to the cleaning liquid injection from the nozzle surface side of the inkjet head.
As shown in FIG. 6, in addition to injecting cleaning liquid from the nozzle surface side of the inkjet head 44, a vacuum suction device is connected to the ink supply port 12 side formed in the frame member 10 of the inkjet head 44 to supply ink. The cleaning liquid is sucked by the suction pump 25 through the suction pipe 26 connected to the port 12, and the flow rate of the cleaning liquid flowing in the ink jet head is changed to generate pulsation, thereby improving the filling performance of the cleaning liquid into the ink jet head.

FIG. 7 is a plan view showing a plurality of communication holes formed in the flow path plate and a liquid chamber serving as an ink flow path, and shows a state in which foreign matter is caught in the ink flow path.
In a state where the foreign matter 28 is caught in the ink flow path formed of the liquid chamber 3 formed in the flow path plate 1, the suction by the vacuum suction device from the ink supply port 12 side is temporarily stopped, and is 0.5 to 2.0 seconds. As shown in FIG. 7, the foreign matter 28 caught on the fluid resistance portion 4 is removed and suction is performed again to remove the foreign matter 28.

The cleaning liquid for removing the foreign matter 28 in the ink jet head may be pure water, but in order to remove wettability with the inner wall of the ink flow path and viscous foreign matter, 0.1 to 3.0 wt. It is desirable to use 0.1 to 3.0 wt% of a penetrant.
Moreover, it has been confirmed that not only the cleaning liquid but also the cleaning liquid and air are mixed to generate bubbles to further improve the foreign matter removing effect.

It is sectional drawing which shows the inkjet head to which this invention is applied. It is a perspective view which decomposes | disassembles and shows the inkjet head shown in FIG. FIGS. 3A and 3B are cross-sectional views showing the frame member cut at the ink flow path portion, FIG. 3A shows the frame member of the present invention, and FIG. 3B shows the conventional frame member. FIG. 4A is a plan view showing a plurality of communication holes formed in a flow path plate and a liquid chamber serving as an ink flow path. FIG. 4A shows the communication holes and the liquid chamber of the present invention, and FIG. The communication hole and the liquid chamber are shown. It is a figure which shows a mode that the fan-shaped cap of a washing | cleaning apparatus is closely_contact | adhered to the nozzle surface of an inkjet head, and a washing | cleaning liquid is inject | poured into a nozzle hole. It is a figure which shows a mode that vacuum suction is carried out from the ink supply port side in addition to washing | cleaning liquid injection | pouring from the nozzle surface side of an inkjet head, and improving the washing | cleaning-liquid filling property in an inkjet head. FIG. 5 is a plan view showing a plurality of communication holes formed in a flow path plate and a liquid chamber serving as an ink flow path, and is a view showing a state in which foreign matter is caught in the ink flow path. 1 is a perspective view illustrating a configuration of a main part of an ink jet recording apparatus to which an ink jet head of the present invention is applied. It is a sectional side view of the inkjet recording device of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Flow path plate, 2 ... Communication hole, 3 ... Liquid chamber, 4 ... Fluid resistance part, 5 ... Nozzle plate, 6 ... Nozzle hole, 7 ... Vibrating plate, 8 ... Base member, 9 ... Piezoelectric element, 10 ... Frame 11: Ink flow path, 12: Ink supply port, 12a: Filter mounting portion, 21: Cleaning device, 22 ... Infusion pump, 23 ... Cap, 25 ... Suction pump, 26 ... Suction pipe, 28 ... Foreign matter, 31 ... Recording device main body, 32 ... printing mechanism, 33 ... paper, 34 ... paper feed cassette, 35 ... manual feed tray, 36 ... paper discharge tray, 41 ... main guide rod, 42 ... sub guide rod, 43 ... carriage, 44 ... inkjet Head, 45 ... Ink cartridge, 47 ... Main scanning motor, 48 ... Drive pulley, 49 ... Driven pulley, 50 ... Timing belt, 51 ... Feed roller, 52 ... Friction pad, 53 ... Guide member, DESCRIPTION OF SYMBOLS 4 ... Conveyance roller, 55 ... Conveyance roller, 56 ... End roller, 57 ... Sub scanning motor, 59 ... Printing receiving member, 61 ... Conveyance roller, 62 ... Spur, 63 ... Discharge roller, 64 ... Spur, 65, 66 ... guide member, 67 ... recovery device.

Claims (9)

  An ink jet head having a plurality of pressurized liquid chambers having a fluid resistance portion, a nozzle communicating with the pressurized liquid chamber, and a pressure generating element corresponding to the pressurized liquid chamber, and a flow path through which ink in the ink jet head flows An inkjet head characterized in that the cross-sectional area of the nozzle is minimum and no filter is provided in the flow path.   2. The ink jet head according to claim 1, wherein a corner portion of the wall surface forming the fluid resistance portion is formed in a curved surface.   3. An ink jet recording apparatus for forming an image on a recording medium by ejecting ink droplets from a nozzle by driving energy generated by a pressure generating element corresponding to a pressurized liquid chamber. An ink jet recording apparatus.   3. An ink jet head cleaning apparatus for removing foreign matter from the ink jet head according to claim 1 or 2, wherein a cleaning liquid is injected from a nozzle surface side of the ink jet head by a cleaning liquid injection device, and the nozzle and the pressurized liquid chamber are cleaned. An inkjet head cleaning device characterized by the above.   5. The inkjet head cleaning apparatus according to claim 4, wherein the cleaning liquid injection pressure of the cleaning liquid injection apparatus is 0.1 to 0.5 Mpa.   6. The ink jet head cleaning apparatus according to claim 4, further comprising a vacuum suction device for sucking a cleaning liquid from an ink supply unit of the ink jet head.   7. The inkjet head cleaning apparatus according to claim 4, wherein a cleaning liquid is made to flow backward from an ink supply unit of the inkjet head in order to remove a foreign matter caught by a fluid resistance portion of the inkjet head. apparatus.   8. An ink jet head cleaning method using the ink jet head cleaning apparatus according to claim 4, wherein the cleaning liquid includes a surfactant and a penetrating agent.   9. The ink jet head cleaning method according to claim 8, wherein bubbles are generated by sucking air after injecting the cleaning liquid to remove foreign substances adhering to the wall surface in the flow path through which the ink flows. .

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