JP2014180863A - Liquid jet apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet apparatus that suppresses a defect in discharging a liquid and improves continuous discharge characteristics by suppressing a defect in discharging in initial charging.SOLUTION: A liquid jet apparatus includes: a flow passages 52 which communicates with a nozzle opening 56 for jetting a liquid; a piezoelectric actuator 11 which causes pressure change in the flow passage 52; and control means of generating a drive signal for driving the piezoelectric actuator 11. The control means controls driving before charging in which the piezoelectric actuator 11 is driven before a liquid to be discharged as a liquid droplet is charged in the liquid jet head 1 in a state in which the liquid to be discharged as the liquid droplet is not charged in a recording head 1.

Description

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

  A typical example of a liquid ejecting head that ejects droplets is an ink jet recording head that ejects ink droplets. The ink jet recording head includes, for example, a flow path forming substrate having a pressure generation chamber communicating with a nozzle opening, and a piezoelectric actuator provided on the other surface side of the flow path forming substrate via a vibration plate. In addition, there has been proposed an apparatus in which an ink droplet is ejected from a nozzle opening by deforming a diaphragm by driving a piezoelectric actuator and causing a pressure change in a pressure generating chamber.

  In such an ink jet recording head, ink is discharged as ink droplets (droplets) from a state where ink (liquid) discharged as ink droplets (droplets) is not filled in a flow path such as a pressure generation chamber. When performing so-called initial filling with ink (liquid) for the first time, the number of nozzle openings is large, so pressure is not evenly distributed to each nozzle opening, resulting in poor filling, poor ejection, and continuous ejection. There is a problem that is damaged.

  For this reason, in order to suppress ink filling failure, for example, there is a method of discharging (suctioning) a large amount of ink from the nozzle opening, but there is a problem that a large amount of ink must be discarded.

  In addition, for example, there has been proposed an ink filling property that is improved by filling a highly hydrophilic storage solution at the time of shipment (see, for example, Patent Document 1).

  Furthermore, in order to discharge bubbles and foreign matters contained in the ink, a filling method has been proposed in which high-frequency vibration is applied to the ink so that the bubbles are ruptured so that the bubbles and foreign matters are easily discharged (for example, Patent Documents). 2).

JP 2004-114647 A JP 2008-230012 A

However, even if any of the above methods is used, there is a risk that a filling failure after the initial filling may occur depending on the ink, the flow path structure, and the like, and further suppression of the filling failure is desired.
Such a problem exists not only in an ink jet recording apparatus that ejects ink but also 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 suppresses a filling failure at the time of initial filling, improves a liquid discharge failure, and improves continuous discharge characteristics.

An aspect of the present invention that solves the above problems includes a flow path that communicates with a nozzle opening that ejects liquid, a piezoelectric actuator that causes a pressure change in the flow path, and a control means that generates a drive signal that drives the piezoelectric actuator. A liquid ejecting apparatus including the liquid ejecting head, wherein the control unit ejects the liquid ejecting head as droplets from a state in which the liquid ejecting the liquid ejecting head as liquid droplets is not filled. In the liquid ejecting apparatus, the pre-filling drive for driving the piezoelectric actuator is performed before the liquid to be filled is filled.
In such an embodiment, from the state where the liquid ejected as droplets is not filled, the piezoelectric actuator is driven to generate heat before filling the liquid ejected as droplets, thereby heating the flow path. It is possible to improve the wettability of the flow path and suppress liquid filling defects.

  Here, it is preferable that the control means controls the number of times the piezoelectric actuator is driven. According to this, it is possible to easily adjust the temperature of the liquid ejecting head by controlling the heat generation amount by the number of times of driving.

  Moreover, it is preferable that the control means drives the piezoelectric actuator corresponding to the selected nozzle opening with respect to the plurality of nozzle openings. According to this, it is possible to easily adjust the temperature of the liquid ejecting head by controlling the amount of heat generated by controlling the number of driving the piezoelectric actuator.

  Preferably, the control means controls the driving of the piezoelectric actuator, and lowers the voltage applied to the piezoelectric actuator during the pre-filling driving than the voltage applied to the piezoelectric actuator during droplet ejection. According to this, it is possible to extend the life by suppressing the destruction of the piezoelectric actuator.

1 is a schematic perspective view of a recording apparatus according to Embodiment 1 of the present invention. FIG. 3 is a cross-sectional view of the recording head according to the first embodiment of the invention. It is a block diagram which shows the control system which concerns on Embodiment 1 of this invention. It is a drive waveform which shows the drive signal which concerns on Embodiment 1 of this invention. 3 is a flowchart showing an operation of the recording apparatus according to the first embodiment of the invention.

Hereinafter, the present invention will be described in detail based on embodiments.
(Embodiment 1)
FIG. 1 is a schematic perspective view of a recording apparatus according to Embodiment 1 of the present invention.
An ink jet recording head 1 (hereinafter also referred to as recording head 1) is provided with an ink cartridge 2 constituting an ink supply means in a detachable manner, and a carriage 3 on which the recording head 1 is mounted is attached to an apparatus main body 4. The carriage shaft 5 is provided so as to be movable in the axial direction. For example, the recording head 1 ejects a black ink composition and a color ink composition.

  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.

  In addition, in a non-printing region on one end side in the moving direction of the carriage 3 of the ink jet recording apparatus I, ink or bubbles in the flow path are discharged from a nozzle opening 56 (see FIG. 2) of the recording head 1 described later in detail. A suction means 110 for sucking is provided.

  The suction unit 110 includes a cap member that covers the liquid ejection surface of the recording head 1 and a suction device such as a vacuum pump that is connected to the cap member via a tube or the like, although not particularly illustrated.

The suction means 110 having such a configuration causes the cap member to abut the liquid ejection surface of the recording head 1 and causes the suction device to perform a suction operation, thereby causing the inside of the cap member to flow negatively from the nozzle opening 56. Suction ink and gas in the road. By the suction of the suction means 110, initial filling for filling the flow path in the recording head 1 with ink and cleaning by sucking the ink in the flow path together with bubbles are performed. Further, during printing suspension, drying of the nozzle openings 56 may be suppressed by sealing the nozzle openings 56 with a cap member.
The ink jet recording apparatus I is provided with a control device 100 which is a control means for controlling the operation of the ink jet recording apparatus I, as will be described in detail later.

  Here, the ink jet recording head 1 mounted on the ink jet recording apparatus I will be described. FIG. 2 is a cross-sectional view illustrating an ink jet recording head which is an example of a liquid ejecting head according to Embodiment 1 of the invention.

  As shown in FIG. 2, the flow path forming substrate 50 is made of a silicon single crystal substrate, and a pressure generation chamber 52 defined by a plurality of partition walls 51 is formed in the width direction (short side) on the surface layer portion on one surface side. Direction). Further, a manifold 53 for supplying ink, which is an example of liquid, to each pressure generating chamber 52 is disposed on one end in the longitudinal direction of each pressure generating chamber 52 via an ink supply path 54, which is an example of a liquid supply path. It is communicated. Further, a nozzle plate 57 which is an example of a nozzle forming member in which the opening surface side of the pressure generating chamber 52 of the flow path forming substrate 50 is sealed with a vibration plate 55 and the nozzle opening 56 is formed on the other surface side is bonded. It is bonded via an agent or a heat welding film.

  The diaphragm 55 formed on the flow path forming substrate 50 includes, for example, an elastic film 55a made of an elastic member such as a resin film, and a support plate 55b made of, for example, a metal material that supports the elastic film 55a. It is formed of a composite plate, and the elastic film 55 a side is bonded to the flow path forming substrate 50. For example, in the present embodiment, the elastic film 55a is made of a PPS (polyphenylene sulfide) film having a thickness of about several μm, and the support plate 55b is made of a stainless steel plate (SUS) having a thickness of about several tens of μm. In addition, an island portion 59 with which the tip of the piezoelectric actuator 11 abuts is provided in a region of the diaphragm 55 that faces each pressure generating chamber 52. That is, a thin portion 60 that is thinner than other regions is formed in a region of the diaphragm 55 that faces the peripheral portion of each pressure generating chamber 52, and an island portion 59 is provided inside each thin portion 60. Yes. In the present embodiment, the diaphragm 55 is provided with the island portion 59 so that the diaphragm 55 is provided with a thick portion thicker than other regions (thin portions 60).

  Further, in the region facing the manifold 53 of the vibration plate 55, similarly to the thin portion 60, a compliance portion 61 that is substantially composed only of the elastic film 55 a is provided by removing the support plate 55 b by etching. . The compliance portion 61 absorbs the pressure change by the deformation of the elastic film 55a of the compliance portion 61 when a pressure change occurs in the manifold 53, and always keeps the pressure in the manifold 53 constant. Fulfill.

  A head case 58 having an ink supply path that is an example of a liquid supply path that is connected to an ink cartridge that is an example of a plurality of liquid reservoirs (not shown) is fixed on the vibration plate 55. The piezoelectric actuator unit 10 is positioned and fixed with high accuracy. That is, the head case 58 is provided with a housing portion 58 a that penetrates, the piezoelectric actuator unit 10 is provided on one inner surface of the housing portion 58 a, and the pressure generating chambers 52 on the vibration plate 55 have the tip ends of the piezoelectric actuators 11. Are bonded and fixed to each island portion 59 (thick portion) provided in a region corresponding to 1 through an adhesive 63.

  Here, the piezoelectric actuator unit 10 includes a piezoelectric actuator forming member 13 having a row in which a plurality of piezoelectric actuators 11 are arranged in the width direction, and a distal end (one end) side of the piezoelectric actuator forming member 13 is a free end. As described above, the base end portion (the other end portion) side has a fixed plate 14 joined as a fixed end.

  The piezoelectric actuator forming member 13 includes a piezoelectric material layer 15, internal electrodes constituting two poles of the piezoelectric actuator 11, that is, individual electrodes 16 that are electrically independent from the adjacent piezoelectric actuator 11, and adjacent piezoelectric actuators 11. It is formed by alternately stacking common electrodes 17 that are electrically common.

  The piezoelectric actuator forming member 13 is formed with a plurality of slits 18 by, for example, a wire saw or the like, and the ends of the slits are cut into comb teeth to form a row of piezoelectric actuators 11.

  The region joined to the fixed plate 14 of the piezoelectric actuator 11 is an inactive region that does not contribute to vibration, and when a voltage is applied between the individual electrode 16 and the common electrode 17 constituting the piezoelectric actuator 11, the fixed plate Only the region on the tip end side that is not joined to 14 vibrates.

  In such a piezoelectric actuator unit 10, the surface of the fixing plate 14 opposite to the surface on which the piezoelectric actuator forming member 13 is fixed is fixed to the accommodating portion 58 a of the head case 58. Further, the front end surface of each piezoelectric actuator 11 is bonded to the island portion (thick portion) 59 of the diaphragm 55 via the adhesive 63.

  Further, a wiring board 33 provided with a plurality of conductive pads 32 to which the respective wirings 31 of the circuit board 30 are respectively connected is fixed on the head case 58, and the accommodating portion 58a of the head case 58 is provided with this wiring. The substrate 33 is substantially blocked. The wiring board 33 is formed with a slit-shaped opening 34 in a region facing the housing portion 58a of the head case 58, and the circuit board 30 is bent from the opening 34 of the wiring board 33 to the outside of the housing portion 58a. Being pulled out.

  The circuit board 30 is provided with a temperature detection unit 35 such as a temperature sensor for detecting the temperature of the recording head 1. The temperature detection unit 35 may be provided on the circuit board 30 or the like, or may be provided on the surface of the head case 58 on a surface different from the surface on which the wiring substrate 33 is provided.

  Here, the circuit board 30 constituting the piezoelectric actuator unit 10 is made of, for example, a chip-on-film (COF) on which a driving IC (not shown) for driving the piezoelectric actuator 11 is mounted in the present embodiment. Each wiring 31 of the circuit board 30 is connected to the individual electrode 16 and the common electrode 17 constituting the piezoelectric actuator 11 by, for example, solder, anisotropic conductive material, or the like on the base end side. On the other hand, each wiring 31 is joined to each conductive pad 32 of the wiring board 33 on the tip side. Specifically, each wiring 31 is connected to the wiring board 33 in a state in which the front end portion of the circuit board 30 drawn out from the opening 34 of the wiring board 33 to the outside of the housing portion 58 a is bent along the surface of the wiring board 33. The conductive pads 32 are joined.

  In such an ink jet recording head 1, when ejecting ink droplets, the volume of each pressure generating chamber 52 is changed by deformation of the piezoelectric actuator 11 and the diaphragm 55, and ink droplets are ejected from predetermined nozzle openings 56. It is designed to be discharged. Specifically, when ink is supplied from the ink cartridge 2 shown in FIG. 1 to the manifold 53, the ink is distributed to each pressure generating chamber 52 via the ink supply path 54. Actually, the piezoelectric actuator 11 is contracted by applying a voltage to the piezoelectric actuator 11. As a result, the diaphragm 55 is deformed together with the piezoelectric actuator 11 to expand the volume of the pressure generating chamber 52, and ink is drawn into the pressure generating chamber 52. Then, after the ink is filled up to the nozzle opening 56, the voltage applied to the individual electrode 16 and the common electrode 17 of the piezoelectric actuator 11 is released according to the recording signal supplied via the wiring substrate 33. As a result, the piezoelectric actuator 11 is expanded to return to the original state, and the diaphragm 55 is also displaced to return to the original state. As a result, the volume of the pressure generation chamber 52 contracts, the pressure in the pressure generation chamber 52 increases, and ink droplets are ejected from the nozzle openings 56.

  Here, the control device 100 for controlling the ink jet recording apparatus I including the ink jet recording head 1 will be described. FIG. 3 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. 3, in the ink jet recording apparatus I, the recording head 1 serving as a mechanism unit that performs actual printing, the suction unit 110 that sucks ink from the nozzle openings 56 of the recording head 1, the recording head 1, and the suction And a control device 100 for controlling the operation of the means 110.
The control device 100 includes a print control unit 101, a recording head drive circuit 102, a print position control unit 103, and a suction control unit 104.

  The printing control unit 101 controls the printing operation of the recording head 1, for example, by applying a driving pulse to the piezoelectric actuator 11 via the recording head driving circuit 102 in response to the input of a printing signal, thereby supplying ink from the recording head 1. Discharge.

  Further, the print control unit 101 controls the driving of the piezoelectric actuator 11 before the initial filling, which will be described in detail later, based on the temperature of the recording head detected by the temperature detection unit 35 (drive before filling). Of course, the print control unit 101 corrects the drive signal based on the temperature of the recording head detected by the temperature detection unit 35 so that the ink droplet ejection characteristics are optimal for the temperature of the recording head 1, and the piezoelectric actuator 11. May be driven.

  The print position control means 103 performs positioning in the main scanning direction and sub-scanning direction such as during printing, capping, and cleaning operation of the recording head 1. Specifically, the printing position control means 103 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. That is, the main scanning direction is the moving direction of the carriage 3, and the sub-scanning direction is the direction that intersects the main scanning direction, in this embodiment, the conveyance direction of the recording sheet S. The printing position control means 103 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. When capping such as when printing is stopped or during a cleaning operation, the carriage 3 on which the recording head 1 is mounted is moved to the suction means 110 provided in the non-printing area.

The suction control unit 104 controls the suction operation of the suction unit 110. That is, the suction control unit 104 operates the suction device of the suction unit 110 at a predetermined timing, and causes the suction unit 110 to perform the suction operation of the gas or liquid (ink) in the flow path of the recording head 1. Specifically, the suction control unit 104 moves the recording head 1 to a position facing the suction unit 110 via the printing position control unit 103, and drives the suction device by capping the recording head 1 with a cap member of the suction unit. The suction operation is performed.
Such a suction control unit 104 causes a suction operation to be performed at a predetermined timing such as a cleaning operation or, more specifically, at the initial filling of ink, which will be described later.

  Here, a drive signal applied to the piezoelectric actuator 11 by the print control unit of the present embodiment will be described with reference to FIG. FIG. 4 is a drive waveform showing the drive signal of this embodiment.

The drive waveform input to the piezoelectric actuator 11 is applied to the individual electrodes with the common electrode as a reference potential (0 V in this embodiment).
Drive waveform of a drive signal for driving the piezoelectric actuator 11 during normal printing 120, as shown in FIG. 4 (a), the first expansion element is raised from the state of maintaining the intermediate potential V _m to a first potential V ₁ P01 When, comprises first hold element P02 maintaining the first electric potential _{V 1} given time, a first contraction element P03 lowering from the electric potential _{V 1} to the intermediate potential _{V m,} a. When such a drive waveform 120 is supplied to the piezoelectric actuator 11, the first expansion element P 01 causes the piezoelectric actuator 11 to deform in a direction in which the volume of the pressure generating chamber 52 is expanded, and the meniscus in the nozzle opening 56. Is drawn to the pressure generating chamber 52 side, and ink is supplied to the pressure generating chamber 52 from the manifold 53 side. The expanded state of the pressure generating chamber 52 is maintained by the first hold element P02. Next, the first contraction element P03 is supplied and the piezoelectric actuator 11 extends. As a result, the pressure generation chamber 52 is rapidly contracted from the expansion volume to the volume corresponding to the intermediate potential Vm, the ink in the pressure generation chamber 52 is pressurized, and ink droplets are ejected from the nozzle openings 56. The drive waveform 120 including the first expansion element P01, the first hold element P02, and the first contraction element P03 is repeatedly generated at a constant period T and selectively applied to the piezoelectric actuator 11 at a predetermined timing. The

  On the other hand, the print control unit of the present embodiment drives the piezoelectric actuator 11 (first driving before filling) to heat the recording head 1 before the ink discharged from the recording head is first filled.

  Here, the initial filling means that the ink used for ejection is filled for the first time from the state where the recording head 1 is not filled with the ink used for ejection. That is, ink ejected as ink droplets from a state in which the flow path of the recording head 1 is empty (filled with gas) or a state in which liquid that is not used for ejection, such as protective liquid for transportation, is filled. Says that will be filled.

  In the present embodiment, when the recording head 1 is heated before the initial filling, a voltage lower than the voltage applied when ejecting ink droplets is applied to the piezoelectric actuator 11.

That is, the driving waveform of the driving signal to be applied before the initial filling, as shown in FIG. 4 (b), is raised from the state of maintaining the intermediate potential V _m second to a potential V ₂ lower than the electric potential V ₁ includes a second expansion element P11, a second hold element P12 maintaining the second electric potential _{V 2} fixed time, and the second contraction element P13 of lowering from the second potential _{V 2} to the intermediate potential _{V m,} a. When such a drive waveform 121 is supplied to the piezoelectric actuator 11, the piezoelectric actuator 11 generates heat by driving. At this time, the second electric potential V ₂ are the voltage lower than the first potential V ₁ of the driving waveform 120 to be used for ejecting the ink, the piezoelectric actuator 11 is not easily destroyed, that the life of the piezoelectric actuator 11 is shortened Can be suppressed. That is, when the piezoelectric actuator 11 is driven in a state where the flow path such as the pressure generation chamber 52 is not filled with ink, since there is no ink resistance, the piezoelectric actuator 11 is displaced more than when ink is ejected. For this reason, if the same voltage as the voltage (first potential V ₁ ) when ink is ejected is applied to the piezoelectric actuator 11 in a state where the ink is not filled in the flow path, the piezoelectric actuator 11 may be excessively mutated and destroyed. This is because there is a risk that a part of the polarization is fixed to cause a decrease in displacement.

  Here, the wettability (contact angle) depends on the temperature, and the wettability improves (the contact angle decreases) if the temperature of the member in which the flow path is formed increases. For this reason, heating the recording head 1 by driving the piezoelectric actuator 11 improves the wettability of the flow paths formed in the head case 58, the flow path forming substrate 50, etc., and suppresses ink filling failure. Can do.

  Here, the operation of the ink jet recording apparatus I, particularly the initial filling operation will be described. FIG. 5 is a flowchart showing the initial filling operation of the ink jet recording apparatus of the present embodiment.

  As shown in FIG. 5, when the ink cartridge 2 is attached in step S1, the print control unit 101 determines whether or not initial filling is performed. This determination may be made, for example, by providing a switch to be inserted when the ink cartridge 2 is attached, a sensor for identifying attachment / detachment of the ink cartridge 2, or the like at a portion where the ink cartridge 2 is attached. A user who uses the ink jet recording apparatus I may make a determination by turning on a switch or the like.

  If it is determined in this step S1 that it is not initial filling (step S1: No), the printing position control means 103 moves the carriage 3 to a non-printing area opposite to the suction means 110 in step S4, and suction is performed. The control unit 104 controls the suction unit 110 to cause the suction unit 110 to perform a suction operation from the nozzle opening 56 side, thereby filling the ink of the ink cartridge 2 into the flow path of the ink jet recording head 1 (initial filling). Operation).

  When it is determined in step S1 that the initial filling is performed (step S1: Yes), in step S2, the print control unit 101 determines that the temperature of the recording head 1 is equal to or higher than a predetermined temperature based on the temperature detected by the temperature detection unit 35. Judge whether it became. When it is determined in step S2 that the temperature of the recording head 1 has not reached the predetermined temperature (step S2: No), in step S3, the print control unit 101 applies the heating drive waveform 121 described above to the piezoelectric actuator 11. The recording head is heated by inputting and driving the piezoelectric actuator 11. That is, the recording head 1 is heated by repeating Steps S2 and S3 until the recording head 1 reaches a predetermined temperature.

  If the print control means 101 determines in step S2 that the temperature of the recording head 1 has become equal to or higher than the predetermined temperature (step S2: Yes), the print position control means 103 moves the carriage 3 relative to the suction means 110 in step S4. The suction control unit 104 controls the suction unit 110 to cause the suction unit 110 to perform a suction operation from the nozzle opening 56 side, so that the ink in the ink cartridge 2 is transferred to the inkjet recording head 1. It fills in the flow path.

As described above, when the recording head 1 is initially filled with the ink used for ejection of the recording head 1, the piezoelectric actuator 11 is driven to generate heat, and the recording head 1 is heated to a predetermined temperature. The ink can be surely filled in the flow path. In particular, the pressure can be evenly distributed to the individual flow paths such as the pressure generating chambers 52 communicating with the nozzle openings 56, and the defective filling of the ink into the individual flow paths can be suppressed, resulting in poor discharge and continuous after filling. It is possible to suppress ejection failure during ejection. For this reason, since the cross-sectional area of the flow path is reduced or the shape is complicated, even if the flow path resistance is increased, poor filling can be suppressed. Densification can be realized.
Further, since the wettability of the flow path can be improved and filling failure can be suppressed, it is not necessary to suck a large amount of ink by the suction means, and wasteful ink consumption can be suppressed.

  Further, in the present embodiment, the temperature detection unit 35 is provided in the recording head 1 and is driven so that the temperature of the recording head 1 detected by the temperature detection unit 35 does not become higher than a predetermined temperature. For this reason, it can suppress that the recording head 1 is overheated and the recording head 1 is destroyed by heat. For example, when the temperature at which the drive IC (not shown) mounted on the circuit board 30 of the recording head 1 is destroyed is the lowest temperature among the components constituting the recording head 1, the drive IC is destroyed. The recording head 1 may be heated so as not to reach a certain temperature.

  In this embodiment, a voltage lower than the voltage applied when ink is ejected to the piezoelectric actuator 11 before the initial filling is applied. Thereby, the drive voltage which drives the piezoelectric actuator 11 in the state where the ink is not filled in the flow path can be lowered, the destruction of the piezoelectric actuator 11 can be suppressed, and the life of the piezoelectric actuator 11 can be extended.

(Other embodiments)
As mentioned above, although one Embodiment of this invention was described, the basic composition of this invention is not limited to what was mentioned above.

  For example, in the above-described embodiment, the temperature detection unit 35 is provided in the recording head 1 and the piezoelectric actuator 11 is driven based on the temperature of the recording head 1 detected by the temperature detection unit 35. For example, without providing the temperature detection unit 35, in the case of initial filling, the piezoelectric actuator 11 may be driven a certain number of times and time. Of course, the driving of the piezoelectric actuator 11 may be appropriately changed based on the temperature of the recording head 1 detected by the temperature detector 35, for example, the number of the piezoelectric actuators 11 to be driven, the number of times of driving, and the driving time. . For example, when the difference between the target temperature and the actual temperature of the recording head 1 is large, the number of piezoelectric actuators 11 that are driven simultaneously may be increased, and the target temperature and the actual temperature of the recording head 1 may be increased. If the difference is small, the number of piezoelectric actuators 11 that are driven simultaneously may be reduced. Similarly, the number of driving times, driving time, and the like can be adjusted. As described above, by appropriately changing the driving conditions (the number of simultaneous driving, the number of times of driving, the driving time, etc.) of the piezoelectric actuator 11 according to the detected temperature, it is possible to prevent the piezoelectric actuator 11 from performing unnecessary driving. Thus, it is possible to suppress the life of the piezoelectric actuator 11 from being reduced.

  In Embodiment 1 described above, the piezoelectric actuator 11 is driven before the initial filling. However, the present invention is not particularly limited to this, and the piezoelectric actuator 11 may be driven before and during the initial filling. .

  Furthermore, in the above-described embodiment, as the pressure generating means for causing the pressure change in the flow path (pressure generating chamber), the piezoelectric material layers 15, the individual electrodes 16, and the common electrode 17 are alternately stacked to expand and contract in the axial direction. Although the longitudinal vibration type piezoelectric actuator 11 is exemplified, the pressure generating means is not particularly limited to this, and the piezoelectric material layers and the electrodes are alternately stacked, and one end portion in the stacking direction is formed on the vibration plate 55. You may make it use the lateral vibration type piezoelectric actuator to contact | abut. Further, as the pressure generating means, for example, a thin film type piezoelectric actuator in which a lower electrode, a piezoelectric layer made of a piezoelectric material, and an upper electrode are formed and formed by a lithography method may be used, and a green sheet is attached. A thick film type piezoelectric actuator formed by such a method can also be used.

  In the ink jet recording apparatus I described above, the ink jet recording head 1 is mounted on the carriage 3 and moves 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 the above-described example, the ink jet recording apparatus I has a configuration in which the ink cartridge 2 that is a liquid storage unit is mounted on the carriage 3, but is not particularly limited thereto, for example, a liquid storage unit such as an ink tank. May be fixed to the apparatus main body 4 and the storage means and the ink jet recording head 1 may be connected via a supply pipe such as a tube. Further, the liquid storage means may not be mounted on the ink jet recording apparatus.

  In each of the above embodiments, an ink jet recording apparatus has been described as an example of a liquid ejecting apparatus. However, the present invention is intended for all liquid ejecting apparatuses that include a liquid ejecting head, Of course, the present invention can also be applied to a liquid ejecting apparatus including a liquid ejecting head that ejects liquid other than the above. 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 be applied to a liquid ejection apparatus provided with such a liquid ejection head.

  I Inkjet Recording Device (Liquid Ejecting Device), 1 Inkjet Recording Head (Liquid Ejecting Head), 10 Piezoelectric Actuator Unit, 11 Piezoelectric Actuator, 50 Channel Forming Substrate, 52 Pressure Generating Chamber, 58 Head Case, 100 Control Device ( Control means), 101 print control means, 110 suction means, 120, 121 drive waveform

Claims (4)

A flow path communicating with a nozzle opening for ejecting liquid;
A piezoelectric actuator that causes a pressure change in the flow path;
A liquid ejecting apparatus comprising a liquid ejecting head having a control means for generating a drive signal for driving the piezoelectric actuator,
The control means drives before driving the piezoelectric actuator before filling the liquid ejecting liquid droplets onto the liquid ejecting head from a state where the liquid ejecting liquid droplets are not filled on the liquid ejecting head. A liquid ejecting apparatus.   The liquid ejecting apparatus according to claim 1, wherein the control unit controls the number of times the piezoelectric actuator is driven.   The liquid ejecting apparatus according to claim 1, wherein the control unit drives the piezoelectric actuator corresponding to the selected nozzle opening with respect to the plurality of nozzle openings.   The said control means controls the drive of the said piezoelectric actuator, and lowers the voltage applied to the said piezoelectric actuator at the time of the said drive before filling from the voltage applied to the said piezoelectric actuator at the time of droplet discharge. The liquid ejecting apparatus according to claim 3.

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