JP6004158B2 - Liquid ejector - Google Patents

Description

  The present invention relates to a liquid ejecting apparatus that ejects liquid from nozzle openings, and more particularly to an ink jet recording apparatus that ejects ink as liquid.

  A liquid ejecting apparatus including a liquid ejecting head that ejects liquid droplets includes an ink jet recording head that generates pressure in a pressure generating chamber by pressure generating means and ejects ink droplets from nozzles communicating with the pressure generating chamber. An ink jet recording apparatus may be mentioned.

  In such an ink jet recording head, there is a problem that ejection failure such as nozzle clogging occurs due to thickening or sedimentation of ink accompanying a change in ambient environmental temperature. For this reason, a circulation path comprising a supply path for supplying ink from the liquid storage means storing ink to the ink jet recording head and a recovery path for recovering ink from the ink jet recording head to the ink tank is provided. There is one in which the ink of the means and the ink in the ink jet recording head are circulated through a circulation path (see, for example, Patent Document 1).

JP 2008-254196 A

  However, if there is a portion that easily stagnates in the circulation flow path, there is a problem that the precipitated ink in that portion is difficult to stir and cannot be sufficiently stirred.

  For this reason, it is necessary to take measures such as increasing the amount of ink discharged by cleaning, and there is a problem that wasteful ink consumption increases.

  Such a problem is not limited to the ink jet recording apparatus that ejects ink, and similarly exists in a liquid ejecting apparatus that ejects liquid other than ink.

  In view of such circumstances, it is an object of the present invention to provide a liquid ejecting apparatus that can reliably stir liquid and reduce the amount of wasted liquid consumed.

An aspect of the present invention that solves the above-described problem is that a pressure generation chamber that communicates with a nozzle opening that ejects a liquid, a manifold that communicates with the pressure generation chamber, and a flexible structure provided in at least a part of a partition wall of the manifold A compliance section having pressure, pressure generating means for causing a pressure change in the pressure generating chamber, a supply path for supplying liquid from the liquid storing means storing liquid to the manifold, and from the manifold to the liquid storing means A recovery path for recovering the liquid; and a pressure changing means for changing the pressure of the liquid that supplies the liquid from the supply path to the manifold and vibrating the compliance section by the pressure change. In the liquid ejecting apparatus.
In this mode, the liquid is circulated between the liquid storage means and the liquid ejecting head, and the pressure supplied to the manifold is fluctuated, so that the compliance portion can be vibrated to stir the liquid in the manifold.
Here, it is preferable that the pressure fluctuation means fluctuates the pressure of the liquid supplied in a range not exceeding the pressure resistance of the liquid meniscus formed in the nozzle opening. According to this, it is possible to suppress the liquid from leaking from the nozzle opening due to the pressure change in the manifold, thereby suppressing the wasteful consumption of the liquid.
Moreover, it is preferable that the said pressure fluctuation means has a pump provided so that the pressure which pumps the liquid of the said liquid storage means to the said manifold can be adjusted. According to this, the pressure of the liquid supplied to the manifold can be easily adjusted by controlling the pump.
Further, it is preferable that the pressure fluctuation means includes a moving means for moving the liquid storage means in a vertical direction with respect to the manifold. According to this, the pressure of the liquid supplied to the manifold can be easily adjusted by controlling the moving means.
Moreover, it is preferable that the said pressure fluctuation | variation means is fluctuate | varied so that the liquid in the said manifold may become a positive pressure and a negative pressure with respect to atmospheric pressure. According to this, the compliance part can be vibrated most greatly, and further stirring of the liquid can be realized.
According to another aspect, a pressure generating chamber that communicates with a nozzle opening that ejects liquid, a manifold that communicates with the pressure generating chamber, and a compliance portion that is provided in at least a part of a partition wall of the manifold and has flexibility. A pressure generating means for causing a pressure change in the pressure generating chamber, a supply path for supplying the liquid to the manifold from the liquid storing means for storing the liquid, and the liquid being recovered from the manifold to the liquid storing means. And a pressure changing means for changing the pressure of the liquid that supplies the liquid from the supply path to the manifold.
In such an aspect, the liquid can be circulated between the liquid storage means and the liquid ejecting head, and the pressure supplied to the manifold can be varied to vibrate the manifold and stir the liquid in the manifold.

  Here, it is preferable that the pressure fluctuation means fluctuates the pressure of the liquid supplied in a range not exceeding the pressure resistance of the liquid meniscus formed in the nozzle opening. According to this, it is possible to suppress the liquid from leaking from the nozzle opening due to the pressure change in the manifold, thereby suppressing the wasteful consumption of the liquid.

  Moreover, it is preferable that the said pressure fluctuation means has a pump provided so that the pressure which pumps the liquid of the said liquid storage means to the said manifold can be adjusted. According to this, the pressure of the liquid supplied to the manifold can be easily adjusted by controlling the pump.

  Further, it is preferable that the pressure fluctuation means includes a moving means for moving the liquid storage means in a vertical direction with respect to the manifold. According to this, the pressure of the liquid supplied to the manifold can be easily adjusted by controlling the moving means.

  Moreover, it is preferable that the said pressure fluctuation | variation means fluctuates the said circulation amount so that the liquid in the said manifold may become a positive pressure and a negative pressure with respect to atmospheric pressure. According to this, the compliance part can be vibrated most greatly, and further stirring of the liquid can be realized.

1 is a perspective view illustrating a schematic configuration of a recording apparatus according to Embodiment 1. FIG. 1 is a cross-sectional view illustrating a schematic configuration of a recording apparatus according to a first embodiment. FIG. 3 is an exploded perspective view of the recording head according to the first embodiment. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment. FIG. 3 is a block diagram illustrating a control system of the recording apparatus according to the first embodiment. FIG. 3 is a cross-sectional view of a main part of the recording head illustrating the stirring operation according to the first embodiment. FIG. 6 is a cross-sectional view illustrating a schematic configuration of a recording apparatus according to a second embodiment.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is a perspective view illustrating a schematic configuration of an ink jet recording apparatus that is an example of a liquid ejecting apparatus according to Embodiment 1 of the invention, and FIG. 2 is a cross-sectional view illustrating a schematic configuration of the ink jet recording apparatus. .

  As shown in FIGS. 1 and 2, an ink jet recording apparatus I which is an example of a liquid ejecting apparatus includes an ink jet recording head 1. The ink jet recording head 1 (hereinafter also referred to as recording head 1) is provided with a nozzle opening 21 for discharging ink droplets, and a flow path (not shown) communicating with the nozzle opening 21 communicates with a common manifold 100. Yes. In the manifold 100, an introduction path 42 through which ink from the liquid storage means 200 in which ink is stored is supplied, and a discharge path in which ink that has not been ejected from the nozzle openings 21 in the manifold 100 is collected by the liquid storage means 200. 43 is provided so that it may communicate with 43.

  In such a recording head 1, ink from a liquid storage unit 200 in which a liquid to be described later is stored is supplied to the manifold 100 via the introduction path 42, and the ink filled in the manifold 100 is discharged via the discharge path 43. And is collected by the liquid storage means 200. That is, the ink circulates between the liquid storage means 200 and the manifold 100.

  Such a recording head 1 is mounted on a carriage 3, and the carriage 3 is provided on a carriage shaft 5 attached to the apparatus main body 4 so as to be movable in the axial direction.

  Then, the driving force of the driving motor 6 is transmitted to the carriage 3 via a plurality of gears and a timing belt 7 (not shown), so that the carriage 3 on which the recording head 1 is mounted is moved along the carriage shaft 5. On the other hand, the apparatus body 4 is provided with a platen 8 along the carriage shaft 5, and a recording sheet S that is a recording medium such as paper fed by a paper feed roller (not shown) is wound around the platen 8. It is designed to be transported.

  As shown in FIGS. 1 and 2, the ink jet recording apparatus I is provided with a liquid storage unit 200 that is fixed to the apparatus body 4 and stores ink therein. The liquid storage unit 200 includes a supply pipe 210 provided with a supply path 211 for supplying ink to the recording head 1 and a recovery pipe 220 provided with a recovery path 221 for recovering ink from the recording head 1. A circulation channel is formed by connection.

  The supply pipe 210 is made of a tubular member such as a flexible tube, and a supply path 211 is provided therein. One end of the supply pipe 210 is connected to the liquid storage means 200 and the other end is connected to the introduction path 42 of the recording head 1, whereby ink in the liquid storage means 200 is supplied via the supply path 211 and the introduction path 42. To the manifold 100.

  The collection tube 220 is made of a tubular member such as a flexible tube, and a collection path 221 is provided inside. One end of the recovery pipe 220 is connected to the liquid storage unit 200 and the other end is connected to the discharge path 43 of the recording head 1, whereby the ink in the manifold 100 is discharged via the discharge path 43 and the recovery path 221. The liquid is stored in the liquid storage unit 200.

  In the middle of the supply path 211, a pump 230 is provided as a pumping unit that pumps ink from the liquid storage unit 200 to the recording head 1. The ink in the liquid storage unit 200 is supplied to the recording head 1 at a predetermined pressure by pumping the pump 230. The pump 230 is not particularly limited as long as it can pump ink. For example, the pump 230 is a non-volumetric pump such as a centrifugal pump, a diagonal flow pump, or an axial flow pump, or reciprocates or rotates a liquid in a certain spatial volume. A positive displacement pump that changes the volume by movement and gives energy to the liquid, a special type pump using water or steam jet injection force, compressed air, or the like can be used. Further, the pump 230 may be pulsating or non-pulsating. However, as will be described in detail later, since the pump 230 of the present embodiment functions as a pressure fluctuation unit, it is necessary to use a pump whose discharge amount (volume per unit time) is variable.

  Here, an example of the ink jet recording head 1 mounted on the ink jet recording apparatus I will be described in detail with reference to FIGS. 3 is an exploded perspective view of an ink jet recording head that is an example of the liquid ejecting head according to the first embodiment of the invention, and FIG. 4 is a cross-sectional view of the ink jet recording head in the second direction. FIG. 5 is a sectional view of the ink jet recording head in the first direction.

  As shown in FIGS. 3 to 5, the ink jet recording head 1 includes a head main body 11 and a plurality of members such as a case member 40 in which the head main body 11 is accommodated, and the plurality of members are made of adhesive or the like. It is joined. In the present embodiment, the head body 11 includes the flow path forming substrate 10 and the communication plate 15, the nozzle plate 20, and the protective substrate 30.

  In the flow path forming substrate 10, a plurality of pressure generating chambers 12 are juxtaposed along a direction in which a plurality of nozzle openings 21 for discharging the same color ink are juxtaposed. Hereinafter, this direction is referred to as a direction in which the pressure generating chambers 12 are arranged side by side or a first direction X. Further, the flow path forming substrate 10 is provided with a plurality of rows in which the pressure generation chambers 12 are arranged in parallel in the first direction X, and in this embodiment, two rows. An arrangement direction in which a plurality of rows of the pressure generation chambers 12 in which the pressure generation chambers 12 are formed along the first direction X is provided is hereinafter referred to as a second direction Y. An ink supply path 14 is provided on one end side in the first direction X of the pressure generating chamber 12 of the flow path forming substrate 10. An elastic film 50 is formed on one surface of the flow path forming substrate 10, and one surface of the pressure generation chamber 12 and the ink supply path 14 is formed by the elastic film 50.

  A communication plate 15 is bonded to the opening surface side of the flow path forming substrate 10 (the side opposite to the elastic film 50). A nozzle plate 20 having a plurality of nozzle openings 21 communicating with each pressure generating chamber 12 is joined to the communication plate 15. The communication plate 15 is provided with a communication passage 16 that connects the pressure generation chamber 12 and the nozzle opening 21. The communication plate 15 has a larger area than the flow path forming substrate 10, and the nozzle plate 20 has a smaller area than the flow path forming substrate 10. Thus, cost reduction can be achieved by making the area of the nozzle plate 20 relatively small.

  An insulator film 55 is further formed on the elastic film 50 formed on the flow path forming substrate 10. On the insulator film 55, a piezoelectric actuator (pressure generating means) 300 including a first electrode 60, a piezoelectric layer 70, and a second electrode 80 is provided. In the present embodiment, the first electrode 60 functions as a common electrode common to the plurality of piezoelectric actuators 300, and the second electrode 80 functions as an individual electrode independent of each piezoelectric actuator 300. One end of each lead electrode 90 is connected to the second electrode 80. A wiring substrate 121 provided with a drive circuit 120 is connected to the other end of the lead electrode 90.

  A protective substrate 30 having substantially the same size as the flow path forming substrate 10 is bonded to the surface of the flow path forming substrate 10 on the piezoelectric actuator 300 side. The protective substrate 30 has a holding portion 31 that is a space for protecting the piezoelectric actuator 300. The protective substrate 30 is provided with a through hole 32. The other end side of the lead electrode 90 is extended so as to be exposed in the through hole 32, and the lead electrode 90 and the wiring substrate 121 are electrically connected in the through hole 32.

  In addition, a case member 40 is fixed to the head main body 11 having such a configuration. The case member 40 defines a manifold 100 communicating with the plurality of pressure generating chambers 12 together with the head main body 11. The case member 40 includes a recess 41 in which the head body 11 including the flow path forming substrate 10, the communication plate 15, the nozzle plate 20, and the protective substrate 30 is accommodated. The recess 41 has a wider opening area than the flow path forming substrate 10. The opening surface on the nozzle plate 20 side of the recess 41 is sealed by the lid member 110 in a state where the head body 11 is accommodated in the recess 41. As a result, the manifold 100 is defined by the case member 40, the head body 11, and the lid member 110 on the outer periphery of the flow path forming substrate 10. That is, the lid member 110 is bonded to the communication plate 15 and the case member 40 to seal the opening on the nozzle plate 20 side of the manifold 100.

  In this embodiment, such a lid member 110 is made of a flexible thin film (for example, a thin film formed of polyphenylene sulfide (PPS), stainless steel (SUS), or the like), and is slightly larger than the nozzle plate 20. A through hole 111 having an opening has a ring shape provided in the center.

  In this manner, by forming the lid member 110 with a thin film, a region defining the manifold 100 of the lid member 110 functions as a compliance portion 112 that can be deformed by a pressure change in the manifold 100.

  The manifold 100 is provided continuously around the outer periphery of the head body 11. Further, the case member 40 is provided with an introduction path 42 that communicates with the manifold 100 and supplies ink to the manifold 100, and a discharge path 43 that communicates with the manifold 100 and discharges ink of the manifold 100. Yes.

  The introduction path 42 is provided on one side in the first direction X of the head main body 11 so as to communicate with the upper portion of the manifold 100 (the side opposite to the communication plate 15).

  The discharge path 43 is provided on the other side in the first direction X of the head body 11 so as to communicate with the upper portion of the manifold 100.

  As shown in FIG. 2, the introduction path 42 and the discharge path 43 are connected to a supply pipe 210 and a recovery pipe 220 which are tubular members such as tubes connected to the liquid storage means 200 in which external ink is stored. Is done.

  Specifically, the supply pipe 210 has one end connected to the liquid storage unit 200 and the other end connected to the introduction path 42 to supply ink from the liquid storage unit 200 to the case member 40. The recovery pipe 220 has one end connected to the liquid storage unit 200 and the other end connected to the discharge path 43.

  The case member 40 is provided with a connection port 48 that communicates with the through hole 32 of the protective substrate 30 and through which the wiring substrate 121 is inserted. The case member 40 further includes a wall portion 49 at the opening edge of the connection port 48. A wiring board 121 and a connection board 122 connected to the wiring board 121 are fixed to the wall portion 49. The connection board 122 is made of a rigid board provided with a connector 123 to which external wiring is connected, for example.

  In such an ink jet recording head 1, the ink from the liquid storage unit 200 is supplied to the introduction path 42 via the supply path 211 of the supply pipe 210. The ink supplied to the introduction path 42 is supplied from the manifold 100 to each pressure generating chamber 12. Then, in accordance with a signal from the drive circuit 120, the piezoelectric actuator 300 corresponding to the pressure generation chamber 12 is driven to bend and deform, thereby changing the volume of the pressure generation chamber 12 and ejecting ink droplets from the nozzle openings 21. The

  Further, the ink supplied to the manifold 100 of the ink jet recording head 1 is discharged to the recovery path 221 of the recovery pipe 220 via the discharge path 43 and is recovered to the liquid storage means 200 via the recovery path 221. Thereby, sedimentation of the components contained in the ink in the manifold 100 can be suppressed.

  The ink jet recording apparatus I on which the ink jet recording head 1 is mounted is provided with a control device 500 that controls the operation of the ink jet recording apparatus I. Here, a control device 500 for controlling such an ink jet recording apparatus I will be described with reference to FIG. FIG. 6 is a block diagram showing a control system of the recording apparatus according to the first embodiment of the present invention.

  As shown in FIG. 6, the ink jet recording apparatus I includes a recording head 1 serving as a mechanism unit that performs actual printing, a control device 500, and a pump 230.

  The control device 500 includes a print control unit 501, a recording head drive circuit 502, a print position control unit 503, and an agitation control unit 504.

  The print control unit 501 controls the printing operation of the recording head 1, for example, by applying a driving pulse to the piezoelectric actuator 300 via the recording head driving circuit 502 in response to the input of a printing signal, and supplying ink from the recording head 1. Discharge.

  The print position control unit 503 performs positioning in the main scanning direction and the sub scanning direction such as when the recording head 1 is printing or not printing. Specifically, the printing position control means 503 drives the drive motor 6 to move the carriage 3 in the main scanning direction to position the recording head 1 in the main scanning direction, and drives a paper feed motor (not shown) to drive the platen. 8 is rotated to move the recording sheet S in the sub-scanning direction, thereby positioning the recording head 1 with respect to the recording sheet S in the sub-scanning direction. The printing position control unit 503 moves the recording sheet S in the sub-scanning direction while moving the carriage 3 on which the recording head 1 is mounted in the main scanning direction during printing. Further, during non-printing such as during printing standby or cleaning operation, the carriage 3 on which the recording head 1 is mounted is moved to the non-printing area.

  The agitation control unit 504 controls the pump 230 that is the pressure feeding unit of the present embodiment, and varies the supply amount of ink supplied from the liquid storage unit 200 to the ink jet recording head 1. That is, since the pump 230 uses a pump whose discharge amount (volume per unit time) is variable as described above, the stirring control unit 504 changes the discharge amount by controlling the pump 230. As a result, pressure fluctuation can be caused in the ink in the manifold 100.

  Here, the stirring operation by the stirring control means 504 will be described in more detail with reference to FIG. FIG. 7 is a cross-sectional view of the main part of the ink jet recording head showing the stirring operation.

  As shown in FIG. 7A, the stirring control means 504 controls the pump 230 to increase the discharge amount of the pump 230 from the state where the pump 230 supplies ink with the normal discharge amount. As a result, as shown in FIG. 7B, the pressure of the ink in the manifold 100 is increased, and the compliance portion 112 (the lid member 110) is deformed so as to protrude outward (opposite to the manifold 100). In the example shown in FIG. 7B, the compliance portion 112 is deformed so as to protrude outward because the pressure in the manifold 100 becomes positive with respect to the external air pressure.

  Next, as shown in FIG. 7C, the stirring control means 504 controls the pump 230 to reduce the discharge amount of the pump 230. The discharge amount of the pump 230 at this time is a discharge amount lower than the discharge amount of the pump 230 shown in FIG. As a result, the pressure of the ink in the manifold 100 is reduced, and the compliance portion 112 (the lid member 110) is deformed so as to protrude toward the inside (manifold 100 side). In the example shown in FIG. 7C, the compliance portion 112 is deformed so as to protrude inward because the pressure in the manifold 100 becomes negative with respect to the external air pressure.

  By repeatedly performing the steps shown in FIGS. 7B and 7C in this way, the compliance portion 112 of the manifold 100 vibrates and the ink in the manifold 100 is agitated. In other words, the ink in the manifold 100 is supplied from the liquid storage unit 200 and is agitated by circulation that is recovered by the liquid storage unit 200 and agitation by vibrating the compliance unit 112. That is, even if the ink in the manifold 100 is stirred only by circulating the ink between the liquid storage means 200 and the ink jet recording head 1, the ink is not sufficiently stirred in the stagnation region. Although there is a risk of sedimentation of the contained components, the compliance portion 112 is further vibrated to stir the ink in the manifold 100, thereby reducing the stagnation region in the manifold 100 and the ink in the manifold 100. Can be sufficiently stirred. As a result, it is possible to suppress sedimentation of components contained in the ink in the manifold 100 and to suppress ink thickening due to sedimentation of components contained in the ink, and unstable ejection due to thickened ink. And the occurrence of density unevenness in the printed matter due to the components of the ink that has settled, for example, pigment ink can be suppressed.

  Further, in the present embodiment, since the compliance portion 112 is provided on the nozzle plate 20 side of the manifold 100, the compliance portion is disposed when the ink jet recording head 1 is arranged so that the liquid ejection surface where the nozzle opening 21 opens is vertically downward. Reference numeral 112 denotes a bottom surface (downward in the vertical direction) of the manifold 100. For this reason, by vibrating the compliance portion 112, the components settled on the bottom surface of the manifold 100 can be efficiently stirred, and the sedimentation of the components contained in the ink can be suppressed. That is, since the ink component settles down in the vertical direction due to gravity, the sedimented component can be further agitated by providing the compliance portion 112 on the lower side in the vertical direction of the manifold 100.

  Incidentally, the pressure of the ink in the manifold 100 is changed by the pump 230 changing the discharge amount. The pressure change in the manifold 100 does not exceed the pressure resistance of the ink meniscus formed in the nozzle opening 21. Preferably it is done. Of course, by capping the liquid ejection surface on which the nozzle opening 21 opens with a suction cap or a close-up cap, a pressure exceeding the pressure resistance of the meniscus of the nozzle opening 21 can be applied to the manifold 100, but the ink consumption In order to reduce the pressure, it is preferable that the pressure fluctuation in the manifold 100 does not exceed the pressure resistance of the ink meniscus in the nozzle opening 21 as in this embodiment.

  In the present embodiment, the compliance portion 112 is vibrated by setting the pressure in the manifold 100 to a positive pressure and a negative pressure with respect to the external air pressure. However, the present invention is not limited to this. The pressure may be changed to a different pressure within a positive pressure range, and the pressure in the manifold 100 may be changed to a different pressure within a negative pressure range. That is, the pressure in the manifold 100 is not limited to the positive pressure and the negative pressure with respect to the external air pressure, and the compliance unit 112 can be vibrated by changing the pressure in the manifold 100.

  As described above, the ink in the manifold 100 is agitated by the circulation of the ink and the vibration of the compliance unit 112, thereby increasing the viscosity of the ink due to the precipitation of the components contained in the ink and the components of the precipitated ink, for example, pigments. Occurrence of density unevenness of the printed matter due to ink can be suppressed.

  Further, in the present embodiment, since the ink in the manifold 100 can be sufficiently stirred, the frequency of discharging the ink from the nozzle openings 21 by the cleaning operation such as the suction operation is reduced, and wasteful consumption of the ink is performed. Can be reduced.

(Embodiment 2)
FIG. 8 is a cross-sectional view illustrating a schematic configuration of an ink jet recording apparatus which is an example of a liquid ejecting apparatus according to Embodiment 2 of the invention. In addition, the same code | symbol is attached | subjected to the member similar to Embodiment 1 mentioned above, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 8, the ink jet recording apparatus I of the present embodiment includes the ink jet recording head 1, a liquid storage unit 200 that stores ink, and a replenishment unit 240 that replenishes the liquid storage unit 200 with liquid. It has.

  The liquid storage means 200 is provided so as to store ink and to be vertically movable with respect to the ink jet recording head 1. Although not particularly shown, a moving means for moving the liquid storage means 200 up and down in the vertical direction is provided. Examples of the moving means include one using a motor, one using hydraulic pressure, and one using electromagnetic force.

  The replenishing unit 240 includes a storage tank that stores ink therein, and supplies the ink to the liquid storage unit 200. Specifically, the replenishing means 240 is connected to the liquid storage means 200 via a filling pipe 250 in which a replenishing path 251 is provided. Then, the liquid storage means 200 is replenished with ink consumed by being ejected as ink droplets from the ink jet recording head 1. Although not particularly illustrated, a liquid level sensor that detects ink consumption of the liquid storage unit 200, a valve body that opens and closes the replenishment path 251 based on information of the liquid level sensor, and the like are provided.

  In such an ink jet recording apparatus I, the moving means moves the liquid storage means 200 up and down in the vertical direction with respect to the ink jet recording head 1. As a result, the height h between the liquid level of the ink stored in the liquid storage unit 200 and the liquid level of the ink stored in the manifold 100 of the ink jet recording head 1 is changed, resulting in a difference in water head pressure. The pressure for supplying ink to the manifold 100 varies. Thereby, the compliance part 112 can be vibrated similarly to Embodiment 1 mentioned above, and the ink in the manifold 100 can be stirred.

  That is, in this embodiment, the moving unit functions as a pressure changing unit that changes the pressure of the ink supplied from the liquid storing unit 200 to the manifold 100.

(Other embodiments)
As mentioned above, although each embodiment of this invention was described, the fundamental structure of this invention is not limited to what was mentioned above. For example, in each of the above-described embodiments, the compliance portion 112 is provided below the manifold 100 in the vertical direction. However, the present invention is not limited to this. For example, the compliance is provided on the vertical direction of the manifold 100 or on the side surface in the horizontal direction. The portion 112 may be provided.

  In each of the embodiments described above, the thin film type piezoelectric actuator has been described as the pressure generating means for causing a pressure change in the pressure generating chamber 12, but the present invention is not particularly limited thereto. For example, a green sheet is attached. For example, a thick film type piezoelectric actuator formed by a method such as the above, a longitudinal vibration type piezoelectric actuator in which piezoelectric materials and electrode forming materials are alternately stacked and expanded and contracted in the axial direction can be used. Also, as a pressure generating means, a heating element is arranged in the pressure generating chamber, and droplets are discharged from the nozzle opening by bubbles generated by the heat generated by the heating element, or static electricity is generated between the diaphragm and the electrode. Thus, a so-called electrostatic actuator that discharges liquid droplets from the nozzle openings by deforming the diaphragm by electrostatic force can be used.

  Further, in the above-described ink jet recording apparatus I, the ink jet recording head 1 is mounted on the carriage 3 and exemplified to move in the main scanning direction. However, the present invention is not particularly limited thereto. The present invention can also be applied to a so-called line type recording apparatus in which printing is performed simply by moving a recording sheet S such as paper in the sub-scanning direction.

  In each of the above-described embodiments, the ink jet recording apparatus has been described as an example of the liquid ejecting apparatus. However, the present invention is widely intended for all liquid ejecting apparatuses and ejects liquids other than ink. Of course, the present invention can also be applied to a liquid ejecting apparatus. Other liquid ejecting heads include, for example, various recording heads used in image recording apparatuses such as printers, color material ejecting heads used in the manufacture of color filters such as liquid crystal displays, organic EL displays, and FEDs (field emission displays). Examples thereof include an electrode material ejection head used for electrode formation, a bio-organic matter ejection head used for biochip production, and the like, and can also be applied to a liquid ejection apparatus provided with such a liquid ejection head.

  I ink jet recording apparatus (liquid ejecting apparatus), 1 ink jet recording head (liquid ejecting head), 21 nozzle opening, 42 introduction path, 43 discharge path, 100 manifold, 200 liquid storage means, 211 supply path, 221 recovery path, 230 pump, 240 replenishing means, 251 replenishment path, 300 piezoelectric actuator (pressure generating means), 500 control device, 504 stirring control means

Claims (5)

A pressure generating chamber communicating with a nozzle opening for ejecting liquid;
A manifold communicating with the pressure generating chamber;
A flexible compliance portion provided on at least a part of the partition wall of the manifold;
Pressure generating means for causing a pressure change in the pressure generating chamber;
A supply path through which liquid is supplied from the liquid storage means in which liquid is stored;
A recovery path for recovering liquid from the manifold to the liquid storage means;
A liquid ejecting apparatus comprising: a pressure changing unit configured to change a pressure of a liquid that supplies the liquid from the supply path to the manifold, and to vibrate the compliance unit by the pressure change.   2. The liquid ejecting apparatus according to claim 1, wherein the pressure changing unit changes the pressure of the liquid supplied within a range not exceeding a pressure resistance of the liquid meniscus formed in the nozzle opening.   3. The liquid ejecting apparatus according to claim 1, wherein the pressure fluctuation unit includes a pump provided so that a pressure for pumping the liquid in the liquid storage unit to the manifold is adjustable.   The liquid ejecting apparatus according to claim 1, wherein the pressure fluctuation unit includes a moving unit that moves the liquid storage unit in a vertical direction with respect to the manifold. The pressure variation means, according to any one of claims 1 to 4 liquid in the manifold and wherein varying the circulating amount such that the positive and negative pressures relative to atmospheric pressure Liquid ejector.

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