JP7027950B2 - Liquid discharge head, liquid discharge unit, liquid discharge device - Google Patents

Description

The present invention relates to a liquid discharge head, a liquid discharge unit, and a device for discharging a liquid.

In the liquid discharge head, the pressure wave due to the pressure fluctuation when the liquid in the individual liquid chamber is pressurized propagates to the common flow path (also referred to as the common liquid chamber) and reappears to the same individual liquid chamber or another individual liquid chamber. Discharge characteristics deteriorate due to propagating crosstalk (mutual interference).

Conventionally, a plurality of first actuators that are displaced by applying a voltage to change the volume of the pressure chamber to eject the ink liquid from the nozzle holes and the pressure in the common flow path formed on the common flow path by the first actuator. A head having a second actuator that is displaced so as to cancel the fluctuation is known (Patent Document 1).

Japanese Patent No. 4269608

The configuration disclosed in Patent Document 1 described above has a problem that the configuration becomes complicated because the first actuator and the second actuator are individually controlled.

The present invention has been made in view of the above problems, and an object of the present invention is to suppress pressure propagation to a common flow path with a simple configuration.

In order to solve the above problems, the liquid discharge head according to claim 1 of the present invention is
An individual liquid chamber leading to a nozzle that discharges liquid,
A first actuator that pressurizes the liquid in the individual liquid chamber,
The first fluid resistance section leading to the individual liquid chamber and
A second fluid resistance section leading to the first fluid resistance section,
A flow path between fluid resistances, which is interposed between the first fluid resistance portion and the second fluid resistance portion and has a lower fluid resistance than the first fluid resistance portion and the second fluid resistance portion.
It has a second actuator that pressurizes the flow path between fluid resistances, and has.
The first actuator and the second actuator
With a common piezoelectric material,
With individually connected electrodes, including
The fluid resistance of the first fluid resistance section and the fluid resistance of the second fluid resistance section are almost the same.
The exclusion volume of the flow path between fluid resistances is equal to or less than the exclusion volume of the individual liquid chambers.
It was configured.

According to the present invention, pressure propagation to a common flow path can be suppressed with a simple configuration.

It is sectional drawing corresponding to AA line of FIG. 2 along the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 1st Embodiment of this invention. Similarly, it is a cross-sectional explanatory view of a main part along the nozzle arrangement direction. Similarly, it is a plane explanatory view of the flow path composition of the part corresponding to one individual liquid chamber. It is a plane explanatory view of the part corresponding to one individual liquid chamber of the liquid discharge head which concerns on 2nd Embodiment of this invention. It is a plane explanatory view of the part corresponding to one individual liquid chamber of the liquid discharge head which concerns on 3rd Embodiment of this invention. It is a plane explanatory view of the part corresponding to one individual liquid chamber of the liquid discharge head which concerns on 4th Embodiment of this invention. It is sectional drawing explanatory drawing of the part corresponding to one individual liquid chamber of the liquid discharge head which concerns on 5th Embodiment of this invention. It is sectional drawing explanatory drawing of the part corresponding to one individual liquid chamber of the liquid discharge head which concerns on 6th Embodiment of this invention. It is sectional drawing which follows the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 7th Embodiment of this invention. Similarly, it is a plan view of the part corresponding to one individual liquid chamber. It is sectional drawing which follows the direction orthogonal to the nozzle arrangement direction of the liquid discharge head which concerns on 8th Embodiment of this invention. Similarly, it is a plan view of the part corresponding to one individual liquid chamber. It is a plane explanatory view of the main part of the liquid discharge head which concerns on 9th Embodiment of this invention. Is a cross-sectional explanatory view of the individual liquid chamber portion of FIG. It is a plane explanatory view of the main part of an example of the apparatus which discharges a liquid which concerns on this invention. It is explanatory drawing of the main part side surface of the apparatus. It is a plane explanatory view of the main part of another example of the liquid discharge unit which concerns on this invention. It is a front explanatory view of still another example of the liquid discharge unit which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The liquid discharge head according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a cross-sectional explanatory view along a direction orthogonal to the nozzle arrangement direction of the head, FIG. 2 is a schematic cross-sectional explanatory view corresponding to the line AA of FIG. 1, and FIG. 3 also corresponds to one individual liquid chamber. It is a plane explanatory view of the flow path composition of a part.

The liquid discharge head 100 is common to the nozzle plate 1, the flow path plate 2, the diaphragm member 3 which is a wall surface member, the first actuator 11 and the second actuator 12 composed of a piezoelectric element, and the holding substrate 50. It is provided with a flow path member 80.

A plurality of nozzles 4 for discharging liquid are formed on the nozzle plate 1.

The flow path plate 2 forms an individual liquid chamber 6 through which the nozzle 4 communicates, a first fluid resistance portion 71 communicating with the individual liquid chamber 6, and a second fluid resistance portion 72 communicating with the first fluid resistance portion 71. .. Further, the flow path plate 2 is interposed between the first fluid resistance portion 71 and the second fluid resistance portion 72, and is between the fluid resistances having a lower fluid resistance than the first fluid resistance portion 71 and the second fluid resistance portion 72. The flow path 73 and the liquid introduction portion 8 leading to the second fluid resistance portion 72 are formed.

A plurality of individual liquid chambers 6, a first fluid resistance section 71, a second fluid resistance section 72, and a plurality of fluid resistance flow paths 73 are provided corresponding to the plurality of nozzles 4. The liquid introduction unit 8 can be provided corresponding to one or two or more individual liquid chambers 6.

Further, the first fluid resistance section 71 is composed of two fluid resistance paths 71a leading to the individual liquid chambers 6, respectively. Similarly, the second fluid resistance portion 72 is composed of two fluid resistance paths 72a leading to the flow paths 73 between the fluid resistances. The fluid resistance paths 71a and 72a may be one or three or more.

The diaphragm member 3 forms a deformable vibration region 30 that forms a part of the wall surface of the individual liquid chamber 6. Further, an opening 9 leading to the liquid introduction portion 8 is provided.

A first actuator 11 composed of a piezoelectric element integrated with the vibration region 30 is provided on the surface of the vibration plate member 3 on the opposite side of the vibration region 30 from the individual liquid chamber 6.

The first actuator 11 is configured by sequentially laminating and forming a lower electrode 13 as a common electrode, a piezoelectric body 14, and an upper electrode 15 as individual electrodes from the vibration region 30 side. The lower electrode 13, which is a common electrode of the plurality of first actuators 11, is one electrode layer formed over all the first actuators 11 in the nozzle arrangement direction.

The upper electrode 15 which is an individual electrode of the first actuator 11 is covered with an insulating film 17, and the upper electrode 15 is connected to a drive IC which is a drive circuit unit via the individual wiring 16.

Further, in the deformable region 31 of the diaphragm member 3 forming the wall surface of the fluid resistance flow path 73, a piezoelectric element integrated with the deformable region 31 is provided on the surface opposite to the fluid resistance flow path 73. A second actuator 12 to be configured is provided.

The second actuator 12 is configured by sequentially laminating and forming a lower electrode 13 as a common electrode, a piezoelectric body 14, and an upper electrode 15 as individual electrodes from the deformable region 31 side.

Here, the first actuator 11 and the second actuator 12 have a common lower electrode 13, a common piezoelectric body 14, and a common upper electrode 15 which is an electrically connected individual electrode. That is, the piezoelectric body 14 and the upper electrode 15 constituting the first actuator 11 that pressurizes the individual liquid chamber 6 are extended to positions facing the fluid resistance flow path 73.

Then, on the diaphragm member 3, the holding substrate 50 covering the first actuator 11 and the second actuator 12 is bonded with an adhesive.

The holding substrate 50 is formed with an opening 51 interposed between the common flow path 10 and one or more openings 9. Further, the holding substrate 50 is provided with a recess 52 for accommodating the first actuator 11 and the second actuator 12.

The common flow path member 80 forms a common flow path 10 that supplies a liquid to each individual liquid chamber 6.

In the liquid discharge head 100, for example, a voltage falling from the reference potential and rising to the reference potential after the holding period is applied between the upper electrode 15 and the lower electrode 13 of the first actuator 11.

At this time, the first actuator 11 is displaced in the direction of expanding the volume of the individual liquid chamber 6 and then in the direction of reducing the volume of the individual liquid chamber 6 to pressurize the liquid in the individual liquid chamber 6. , The liquid is discharged from the nozzle 4.

Here, since the first actuator 11 and the second actuator 12 have a common piezoelectric body 14 and an upper electrode 15 which is an individual electrode, the second actuator is obtained by applying a voltage to the first actuator 11. 12 is driven in synchronization with the first actuator 11.

As a result, when the liquid in the individual liquid chamber 6 is pressurized, the fluid resistance flow path 73 is also pressurized in synchronization, and the pressure wave generated in the individual liquid chamber 6 is transferred to the common flow path 10 side. When heading, it is hindered by the pressure wave generated in the flow path 73 between the fluid resistances, and the pressure propagation to the common flow path 10 side is suppressed.

In this way, since the second actuator 12 is also driven by driving the first actuator 11, pressure propagation to the common flow path 10 is suppressed and crosstalk due to the common flow path 10 is reduced with a simple configuration. can do.

Here, the fluid resistance of the first fluid resistance portion 71 and the fluid resistance of the second fluid resistance portion 72 are substantially the same, and the exclusion volume of the flow path 73 between the fluid resistances is equal to or less than the exclusion volume of the individual liquid chamber 6. It is supposed to be. The excluded volume is the volume change amount of the individual liquid chamber 6 and the fluid resistance flow path 73 when the first actuator 11 and the second actuator 12 are driven.

That is, when a waveform (PULL waveform) that expands the individual liquid chamber 6 is applied to the first actuator 11, the liquid flows into the individual liquid chamber 6 via the first fluid resistance portion 71. At this time, the second actuator 12 is also displaced in the direction of expanding the fluid resistance flow path 73, and the amount of liquid drawn into the individual liquid chamber 6 via the first fluid resistance portion 71 is reduced by that amount.

By configuring the exclusion volume of the flow path 73 between fluid resistances to be equal to or less than the exclusion volume of the individual liquid chamber 6, it is possible to suppress a decrease in the amount of liquid drawn into the individual liquid chamber 6 via the first fluid resistance portion 71. It is possible to secure the discharge amount.

Further, the upper electrode 15, which is an individual electrode, extends to the fluid resistance flow path 73 through a region facing the fluid resistance path 71a, which is the flow path of the first fluid resistance portion 71.

As a result, the piezoelectric element formed by the piezoelectric body 14, the lower electrode 13, and the upper electrode 15 is also configured in the region of the first fluid resistance portion 71 facing the fluid resistance path 71a, and the fluid resistance of the first fluid resistance portion 71. The region of the piezoelectric body 14 facing the path 71a can be deformed.

Therefore, it is possible to prevent the occurrence of piezoelectric cracks due to stress concentration in the region of the piezoelectric body 14 facing the fluid resistance path 71a due to the displacement of the first actuator 11 and the second actuator 12.

Next, the liquid discharge head according to the second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a plan explanatory view of a portion of the head corresponding to one individual liquid chamber.

In the present embodiment, the fluid resistance of the second fluid resistance unit 72 is lower than the fluid resistance of the first fluid resistance unit 71. The first fluid resistance section 71 and the second fluid resistance section 72 are each composed of one fluid resistance path.

Further, the ratio of the excluded volume to the volume of the flow path 73 between the fluid resistances (excluded volume ratio) is larger than the ratio of the excluded volume to the volume of the individual liquid chamber 6 (excluded volume ratio).

By setting each fluid resistance of the first fluid resistance portion 71 and the second fluid resistance portion 72, and each exclusion volume ratio of the individual liquid chamber 6 and the flow path 73 between the fluid resistances in this way, from the common flow path 10. It is possible to suppress the re-propagation of the pressure wave of the above to the individual liquid chamber 6, reduce crosstalk, and stabilize the discharge characteristics.

That is, by increasing the exclusion volume ratio of the fluid resistance flow path 73, the pressure generating force in the fluid resistance flow path 73 increases. By making the fluid resistance of the second fluid resistance portion 72 relatively small, the generated pressure wave greatly acts on the common flow path 10 side, and a constant pressure acts on the individual liquid chamber 6 side. Will be done. As a result, mutual interference due to the common flow path 10 can be further suppressed.

In this case, the upper part of the individual electrode is the area of the piezoelectric body 14 facing the individual liquid chamber 6 with respect to the ratio of the area of the upper electrode 15 which is the individual electrode to the area of the piezoelectric body 14 facing the flow path between the fluid resistances 73. The ratio of the area of the electrode 15 is reduced.

Thereby, as described above, the exclusion volume ratio of the fluid resistance flow path 73 can be made larger than the exclusion volume ratio of the individual liquid chamber 6. Then, by adjusting the exclusion volume ratio by the area ratio of the individual electrode (upper electrode 15) to the area of the piezoelectric body 14, the area of the piezoelectric body 14 with respect to the vibration region 30 can be secured and the rigidity can be increased equivalently. , The exclusion volume ratio can be adjusted without lowering the resonance frequency.

Next, the liquid discharge head according to the third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a plan explanatory view of a portion of the head corresponding to one individual liquid chamber.

In the present embodiment, the planar shape of the individual liquid chamber 6 is an octagonal shape of 100 × 200 μm, the SOI substrate is used as the diaphragm member 3, and the thickness of Si is also 7 μm.

By increasing the thickness of the vibration region 30, a low aspect ratio individual liquid chamber configuration is provided, and the resonance period of the individual liquid chamber 6 is adjusted to around 6 μs. On the other hand, the compliance of the flow path 73 between the fluid resistances is set to 1/10 or less of the compliance of the individual liquid chamber 6.

That is, if the compliance of the flow path 73 between the fluid resistances becomes large, the resonance period will be extended. Therefore, by setting the compliance of the flow path 73 between the fluid resistances to 1/10 or less of the compliance of the individual liquid chamber 6, it is possible to suppress the extension of the resonance cycle by driving the second actuator 12.

Next, the liquid discharge head according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is a plan explanatory view of a portion of the head corresponding to one individual liquid chamber.

In the present embodiment, the piezoelectric body 14 is formed so as to face the partition wall 71b between the fluid resistance passage 71a and the fluid resistance passages 71a and 71a of the first fluid resistance portion 71. On the other hand, the upper electrode 15 which is an individual electrode is formed so as to face the partition wall 71b, and the width W2 of the upper electrode 15 (width in the nozzle arrangement direction) is 1/3 or less of the width W1 of the piezoelectric body 14.

The displacement of the piezoelectric body 14 is constrained in the region forming the upper electrode 15. When the width of the upper electrode 15 which is an individual electrode is widened, the deformation force of the piezoelectric body 14 itself tends to cause cracks in the piezoelectric body 14 at the edge portion of the first fluid resistance portion 71.

Therefore, by reducing the width of the upper electrode 15 to 1/3 or less of the width of the piezoelectric body 14, it is possible to prevent the occurrence of cracks in the piezoelectric body 14 at the edge portion of the first fluid resistance portion 71, and to prevent the occurrence of cracks in the piezoelectric body 14. It is possible to reduce the deformation force while ensuring the rigidity of itself.

Next, the liquid discharge head according to the fifth embodiment of the present invention will be described with reference to FIG. 7. FIG. 7 is a cross-sectional explanatory view of a portion of the head corresponding to one individual liquid chamber.

In the present embodiment, the lower electrode 13 serving as a common electrode is not provided in the region facing the first fluid resistance portion 71.

As a result, even if the upper electrode 15 is formed on the piezoelectric body 14, the region of the piezoelectric body 14 facing the first fluid resistance portion 71 is not displaced, so that the piezoelectric body at the edge portion of the first fluid resistance portion 71 is formed. It is possible to prevent the occurrence of 14 cracks.

Next, the liquid discharge head according to the sixth embodiment of the present invention will be described with reference to FIG. FIG. 8 is a cross-sectional explanatory view of a portion of the head corresponding to one individual liquid chamber.

In the present embodiment, in the region facing the first fluid resistance portion 71, the lower electrode 13 is an island-shaped floating electrode layer 13a separated from the individual liquid chamber 6 side and the fluid resistance flow path 73 side.

As a result, even if a voltage is applied to the upper electrode 15, an electric field is not generated in the piezoelectric body 14, so that the piezoelectric body 14 does not displace in the region facing the first fluid resistance portion 71, and the generation of cracks can be prevented.

Further, the lower electrode 13 is a layer necessary for controlling the orientation of the piezoelectric body 14, and by forming the floating electrode layer 13a in an island shape, the piezoelectric body 14 at that portion is controlled to have a <100> orientation. And it becomes easier to ensure the in-plane uniformity of the piezoelectric material.

Next, the liquid discharge head according to the seventh embodiment of the present invention will be described with reference to FIGS. 9 and 10. FIG. 9 is a cross-sectional explanatory view along a direction orthogonal to the nozzle arrangement direction of the head, and FIG. 10 is a plan view of a portion corresponding to one individual liquid chamber.

In the present embodiment, the second fluid resistance portion 72 is a portion of the electrode layer forming the diaphragm member 3 and the upper electrode 15 interposed between the opening 51 of the holding substrate 50 and the flow path plate 2. That is, the first fluid resistance portion 71 and the second fluid resistance portion 72 are arranged on different planes.

Even with this configuration, the second actuator 12 facing the fluid resistance flow path 73 is driven together with the first actuator 11, and crosstalk is achieved by suppressing pressure propagation to the common flow path 10 with a simple configuration. Can be reduced.

Next, the liquid discharge head according to the eighth embodiment of the present invention will be described with reference to FIGS. 11 and 12. FIG. 11 is a cross-sectional explanatory view along a direction orthogonal to the nozzle arrangement direction of the head, and FIG. 12 is a plan view of a portion corresponding to one individual liquid chamber.

This embodiment is an embodiment applied to a flow-through type head (individual liquid chamber circulation type head).

Similar to the first embodiment, the flow path plate 2 communicates with the individual liquid chamber 6 through which the nozzle 4 communicates, the supply-side first fluid resistance portion 71A communicating with the individual liquid chamber 6, and the supply-side first fluid resistance portion 71A. It forms a supply-side second fluid resistance portion 72A. Further, the flow path plate 2 is interposed between the supply side first fluid resistance portion 71A and the supply side second fluid resistance portion 72A, and is from the supply side first fluid resistance portion 71A and the supply side second fluid resistance portion 72A. Also forms a flow path 73A between supply side fluid resistances having low fluid resistance. Further, the flow path plate 2 forms a liquid introduction portion 8A that leads to the second fluid resistance portion 72A on the supply side.

Further, the flow path plate 2 forms a recovery-side first fluid resistance section 71B leading to the individual liquid chamber 6 and a recovery-side second fluid resistance section 72B leading to the recovery-side first fluid resistance section 71B. Further, the flow path plate 2 is interposed between the recovery side first fluid resistance section 71B and the recovery side second fluid resistance section 72B, and is from the recovery side first fluid resistance section 71B and the recovery side second fluid resistance section 72B. Also forms a flow path 73B between the recovery side fluid resistances having a low fluid resistance. Further, the flow path plate 2 forms a liquid lead-out portion 8B that leads to the second fluid resistance portion 72B on the recovery side.

The diaphragm member 3 is provided with an opening 9A through which the liquid introduction portion 8A is communicated and an opening 9B through which the liquid outlet portion 8B is communicated.

Similar to the first embodiment, the first actuator 11 is configured by sequentially laminating and forming a lower electrode 13 as a common electrode, a piezoelectric body 14 and an upper electrode 15 as individual electrodes from the vibration region 30 side.

The supply-side second actuator 12A is provided facing the supply-side fluid resistance flow path 73A, and the recovery-side second actuator 12B is provided facing the recovery-side fluid resistance flow path 73B.

Each of the second actuators 12A and 12B is configured by sequentially laminating and forming a lower electrode 13 as a common electrode, a piezoelectric body 14 and an upper electrode 15 as individual electrodes from the deformable region 31 side.

Here, the first actuator 11 and the second actuators 12A and 12B have a common lower electrode 13, a common piezoelectric body 14, and a common upper electrode 15 which is an electrically connected individual electrode. That is, the piezoelectric body 14 and the upper electrode 15 constituting the first actuator 11 that pressurizes the individual liquid chamber 6 are extended to a position facing the supply side fluid resistance flow path 73A, and become the recovery side fluid resistance flow path 73B. It extends to the opposite position.

In the holding substrate 50, an opening 51A is formed between the supply-side common flow path 10 and one or more openings 9A, and between the recovery-side common flow path 150 and one or more openings 9B. It forms an opening 51B through it.

The common flow path member 80 forms a supply-side common flow path 10 for supplying liquid to each individual liquid chamber 6 and a recovery-side common flow path 150 for collecting liquid from each individual liquid chamber 6.

In the circulation type head according to the present embodiment, when the first actuator 11 is driven to discharge the liquid from the nozzle 4, the liquid not discharged from the nozzle 4 passes through the nozzle 4 and is collected by the first fluid resistance portion 71B on the recovery side. It is returned to the recovery side common flow path 150 via the side fluid resistance flow path 73B, the recovery side second fluid resistance section 72B, the liquid outlet section 8B, the opening 9B, and the opening 51B, and is circulated externally from the recovery side common flow path 150. It is supplied again to the common flow path 10 on the supply side through the path.

Here, when the first actuator 11 is driven to discharge the liquid from the nozzle 4, the supply side second actuator 12A and the recovery side second actuator 12B are also displaced.

As a result, crosstalk on the supply side can be reduced by suppressing pressure propagation to the common flow path 10 on the supply side, and crosstalk on the recovery side can be reduced by suppressing pressure propagation to the common flow path 150 on the recovery side. Can also be reduced.

Next, the liquid discharge head according to the ninth embodiment of the present invention will be described with reference to FIGS. 13 and 14. FIG. 13 is an explanatory plan view of a main part of the head, and FIG. 14 is a cross-sectional explanatory view of an individual liquid chamber portion of FIG. In addition, in FIG. 13, the surface coating is omitted for the piezoelectric body in order to make the figure easier to see.

In the present embodiment, an opening 14a is provided in the piezoelectric body 14 facing the individual liquid chamber 6, and the piezoelectric body 14, the lower electrode 13 serving as a common electrode, and the upper electrode 15 serving as individual electrodes are provided on the peripheral edge of the individual liquid chamber 6. The annular first actuator 11 to be configured is arranged.

A first fluid resistance section 71 leading to the individual liquid chamber 6, a fluid resistance flow path 73 leading to the first fluid resistance section 71, and a second fluid resistance section 72 leading to the fluid resistance flow path 73 are arranged. ..

The second actuator 12 corresponding to the flow path between fluid resistances 73 is composed of a piezoelectric body 14 and a lower electrode 13 common to the first actuator 11, and an upper electrode 115 as an individual electrode, and the upper electrode 115 and the upper electrode 15 Is electrically connected by wiring 116.

As a result, although the individual electrodes are not common to the first actuator 11 and the second actuator 12, the second actuator 12 is also driven when the first actuator 11 is driven, and the wall surface of the fluid resistance flow path 73 is driven. The vibration region that forms is displaced.

Therefore, as in the first embodiment, pressure propagation to the common flow path can be suppressed and crosstalk due to the common flow path can be reduced with a simple configuration.

In each of the above embodiments, the lower electrode is used as a common electrode and the upper electrode is used as an individual electrode. However, the lower electrode may be used as an individual electrode and the upper electrode may be used as a common electrode. can.

Next, an example of the device for discharging the liquid according to the present invention will be described with reference to FIGS. 15 and 16. FIG. 15 is an explanatory plan view of a main part of the device, and FIG. 16 is an explanatory view of a side surface of the main part of the device.

This device is a serial type device, and the carriage 403 is reciprocated in the main scanning direction by the main scanning moving mechanism 493. The main scanning movement mechanism 493 includes a guide member 401, a main scanning motor 405, a timing belt 408, and the like. The guide member 401 is bridged over the left and right side plates 491A and 491B to movably hold the carriage 403. Then, the carriage 403 is reciprocated in the main scanning direction by the main scanning motor 405 via the timing belt 408 bridged between the drive pulley 406 and the driven pulley 407.

The carriage 403 is equipped with a liquid discharge unit 440 in which the liquid discharge head 404 and the head tank 441 according to the present invention are integrated. The liquid discharge head 404 of the liquid discharge unit 440 discharges, for example, liquids of each color of yellow (Y), cyan (C), magenta (M), and black (K). Further, the liquid discharge head 404 is mounted by arranging a nozzle row composed of a plurality of nozzles in a sub-scanning direction orthogonal to the main scanning direction and facing the discharge direction downward.

The liquid stored in the liquid cartridge 450 is supplied to the head tank 441 by the supply mechanism 494 for supplying the liquid stored outside the liquid discharge head 404 to the liquid discharge head 404.

The supply mechanism 494 includes a cartridge holder 451 which is a filling part for mounting the liquid cartridge 450, a tube 456, a liquid feeding unit 452 including a liquid feeding pump, and the like. The liquid cartridge 450 is detachably attached to the cartridge holder 451. Liquid is delivered from the liquid cartridge 450 to the head tank 441 by the liquid feeding unit 452 via the tube 456.

This device includes a transport mechanism 495 for transporting the paper 410. The transport mechanism 495 includes a transport belt 412, which is a transport means, and a sub-scanning motor 416 for driving the transport belt 412.

The transport belt 412 attracts the paper 410 and transports it at a position facing the liquid discharge head 404. The transport belt 412 is an endless belt, and is hung between the transport roller 413 and the tension roller 414. Adsorption can be performed by electrostatic adsorption, air suction, or the like.

Then, the transport belt 412 orbits in the sub-scanning direction by rotationally driving the transport roller 413 via the timing belt 417 and the timing pulley 418 by the sub-scanning motor 416.

Further, on one side of the carriage 403 in the main scanning direction, a maintenance / recovery mechanism 420 for maintaining / recovering the liquid discharge head 404 is arranged on the side of the transport belt 412.

The maintenance / recovery mechanism 420 is composed of, for example, a cap member 421 that caps the nozzle surface (the surface on which the nozzle is formed) of the liquid discharge head 404, a wiper member 422 that wipes the nozzle surface, and the like.

The main scanning movement mechanism 493, the supply mechanism 494, the maintenance / recovery mechanism 420, and the transport mechanism 495 are attached to a housing including the side plates 491A and 491B and the back plate 491C.

In this apparatus configured in this way, the paper 410 is fed onto the transport belt 412 and sucked, and the paper 410 is conveyed in the sub-scanning direction by the circumferential movement of the conveyor belt 412.

Therefore, by driving the liquid ejection head 404 in response to the image signal while moving the carriage 403 in the main scanning direction, the liquid is ejected onto the stopped paper 410 to form an image.

As described above, since this device includes the liquid discharge head according to the present invention, it is possible to stably form a high-quality image.

Next, another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 17 is an explanatory plan view of a main part of the unit.

This liquid discharge unit includes a housing portion composed of side plates 491A, 491B and a back plate 491C, a main scanning movement mechanism 493, a carriage 403, and a liquid among the members constituting the device for discharging the liquid. It is composed of a discharge head 404.

It should be noted that a liquid discharge unit may be configured in which at least one of the above-mentioned maintenance / recovery mechanism 420 and the supply mechanism 494 is further attached to, for example, the side plate 491B of the liquid discharge unit.

Next, still another example of the liquid discharge unit according to the present invention will be described with reference to FIG. FIG. 18 is a front explanatory view of the unit.

This liquid discharge unit includes a liquid discharge head 404 to which a flow path component 444, which is a liquid supply member, is attached, and a tube 456 connected to the flow path component 444.

The flow path component 444 is arranged inside the cover 442. A head tank 441 may be included instead of the flow path component 444. Further, a connector 443 that electrically connects to the liquid discharge head 404 is provided on the upper part of the flow path component 444.

In the present application, the liquid to be discharged may have a viscosity and surface tension that can be discharged from the head, and is not particularly limited, but the viscosity becomes 30 mPa · s or less at room temperature, under normal pressure, or by heating or cooling. It is preferable that it is a thing. More specifically, solvents such as water and organic solvents, colorants such as dyes and pigments, polymerizable compounds, resins, functionalizing materials such as surfactants, biocompatible materials such as DNA, amino acids and proteins, and calcium. , Solvents, suspensions, emulsions, etc. containing edible materials such as natural pigments, such as inks for inkjets, surface treatment liquids, components of electronic and light emitting elements, and formation of electronic circuit resist patterns. It can be used in applications such as liquids and material liquids for three-dimensional modeling.

Piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electric heat conversion elements such as heat-generating resistors, and electrostatic actuators that consist of a vibrating plate and counter electrodes are used as energy sources for discharging liquid. Includes what to do.

The "liquid discharge unit" is a liquid discharge head integrated with functional parts and a mechanism, and includes a collection of parts related to liquid discharge. For example, the "liquid discharge unit" includes a head tank, a carriage, a supply mechanism, a maintenance / recovery mechanism, a main scanning movement mechanism in which at least one of the configurations is combined with a liquid discharge head, and the like.

Here, the term "integration" means, for example, a liquid discharge head and a functional component, a mechanism in which the mechanism is fixed to each other by fastening, bonding, engagement, etc., or one in which one is movably held with respect to the other. include. Further, the liquid discharge head, the functional component, and the mechanism may be configured to be detachable from each other.

For example, as a liquid discharge unit, there is a unit in which a liquid discharge head and a head tank are integrated. In some cases, the liquid discharge head and the head tank are integrated by being connected to each other by a tube or the like. Here, a unit including a filter can be added between the head tank of these liquid discharge units and the liquid discharge head.

Further, as a liquid discharge unit, there is a unit in which a liquid discharge head and a carriage are integrated.

Further, there is a liquid discharge unit in which the liquid discharge head and the scanning movement mechanism are integrated by holding the liquid discharge head movably by a guide member constituting a part of the scanning movement mechanism. In some cases, the liquid discharge head, the carriage, and the main scanning movement mechanism are integrated.

Further, as a liquid discharge unit, there is a carriage to which a liquid discharge head is attached, in which a cap member which is a part of the maintenance / recovery mechanism is fixed, and the liquid discharge head, the carriage, and the maintenance / recovery mechanism are integrated. ..

Further, as a liquid discharge unit, there is a liquid discharge unit in which a tube is connected to a head tank or a liquid discharge head to which a flow path component is attached, and the liquid discharge head and a supply mechanism are integrated. The liquid of the liquid storage source is supplied to the liquid discharge head through this tube.

The main scanning movement mechanism shall include a single guide member. Further, the supply mechanism includes a single tube and a single loading unit.

The "device for discharging a liquid" includes a device provided with a liquid discharge head or a liquid discharge unit and driving the liquid discharge head to discharge the liquid. The device for discharging a liquid includes not only a device capable of discharging a liquid to a device to which the liquid can adhere, but also a device for discharging the liquid into the air or into the liquid.

The "device for discharging the liquid" can also include means for feeding, transporting, and discharging paper to which the liquid can adhere, as well as a pretreatment device, a posttreatment device, and the like.

For example, as a "device that ejects a liquid", an image forming device that is a device that ejects ink to form an image on paper, and a three-dimensional object (three-dimensional object) are formed in layers in order to form a three-dimensional object. There is a three-dimensional modeling device (three-dimensional modeling device) that discharges the modeling liquid into the powder layer.

Further, the "device for discharging a liquid" is not limited to a device in which a significant image such as characters and figures is visualized by the discharged liquid. For example, those that form patterns that have no meaning in themselves and those that form a three-dimensional image are also included.

The above-mentioned "thing to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as a material to which the liquid adheres and adheres, and a material to which the liquid adheres and permeates. Specific examples include paper, recording paper, recording paper, film, recorded media such as cloth, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and media such as inspection cells. Yes, and includes everything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which a liquid can adhere" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can adhere even temporarily.

Further, the "device for discharging the liquid" includes, but is not limited to, a device in which the liquid discharge head and the device to which the liquid can adhere move relatively. Specific examples include a serial type device that moves the liquid discharge head, a line type device that does not move the liquid discharge head, and the like.

In addition, as a "device for ejecting a liquid", a treatment liquid coating device for ejecting a treatment liquid to the paper in order to apply the treatment liquid to the surface of the paper for the purpose of modifying the surface of the paper, etc. There is an injection granulator that granulates fine particles of the raw material by injecting a composition liquid in which the raw material is dispersed in the solution through a nozzle.

In addition, in the term of this application, image formation, recording, printing, printing, printing, modeling, etc. are all synonymous.

1 Nozzle plate 2 Flow plate 3 Vibration plate member 4 Nozzle 6 Individual liquid chamber 10 Common liquid chamber (supply side common liquid chamber)
11 1st actuator 12 2nd actuator 50 Holding board 51 Opening 71 1st fluid resistance part 72 2nd fluid resistance part 73 Flow path between fluid resistance 80 Common flow path member 100 Liquid discharge head 150 Recovery side common liquid chamber 403 Carriage 404 Liquid discharge head 440 Liquid discharge unit

Claims (13)

An individual liquid chamber leading to a nozzle that discharges liquid,
A first actuator that pressurizes the liquid in the individual liquid chamber,
The first fluid resistance section leading to the individual liquid chamber and
A second fluid resistance section leading to the first fluid resistance section,
A flow path between fluid resistances, which is interposed between the first fluid resistance portion and the second fluid resistance portion and has a lower fluid resistance than the first fluid resistance portion and the second fluid resistance portion.
It has a second actuator that pressurizes the flow path between fluid resistances, and has.
The first actuator and the second actuator
With a common piezoelectric material,
With individually connected electrodes, including
The fluid resistance of the first fluid resistance section and the fluid resistance of the second fluid resistance section are almost the same.
A liquid discharge head characterized in that the exclusion volume of the flow path between fluid resistances is equal to or less than the exclusion volume of the individual liquid chambers. The first fluid resistance portion, the flow path between the fluid resistances, and the second fluid resistance portion are
The liquid discharge head according to claim 1, wherein the liquid discharge head is arranged between the supply-side common liquid chamber leading to the plurality of individual liquid chambers and the individual liquid chambers. The first fluid resistance portion, the flow path between the fluid resistances, and the second fluid resistance portion are
The liquid discharge head according to claim 1 or 2, wherein the liquid discharge head is arranged between the collection-side common liquid chamber leading to the plurality of individual liquid chambers and the individual liquid chambers. An individual liquid chamber leading to a nozzle that discharges liquid,
A first actuator that pressurizes the liquid in the individual liquid chamber,
The first fluid resistance section leading to the individual liquid chamber and
A second fluid resistance section leading to the first fluid resistance section,
A flow path between fluid resistances, which is interposed between the first fluid resistance portion and the second fluid resistance portion and has a lower fluid resistance than the first fluid resistance portion and the second fluid resistance portion.
It has a second actuator that pressurizes the flow path between fluid resistances, and has.
The first actuator and the second actuator
With a common piezoelectric material,
The fluid resistance of the electrically connected individual electrodes and the second fluid resistance section including the fluid resistance of the second fluid resistance section is lower than the fluid resistance of the first fluid resistance section.
A liquid discharge head characterized in that the ratio of the excluded volume to the volume of the flow path between fluid resistances is larger than the ratio of the excluded volume to the volume of the individual liquid chamber. The feature is that the ratio of the area of the individual electrode to the area of the piezoelectric body facing the individual liquid chamber is small with respect to the ratio of the area of the individual electrode to the area of the piezoelectric body facing the flow path between the fluid resistances. The liquid discharge head according to claim 4. One of claims 1 to 5, wherein the individual electrode extends from a region facing the individual liquid chamber to a position facing the flow path between the fluid resistances via the first fluid resistance portion. The liquid discharge head described in. The liquid discharge head according to claim 6, wherein the individual electrode is formed in a region facing the flow path of the first fluid resistance portion. The liquid discharge head according to claim 6, wherein the width of the individual electrode is 1/3 or less of the width of the piezoelectric body in the region facing the first fluid resistance portion. The liquid discharge head according to claim 2, wherein the first fluid resistance portion is arranged on a plane different from that of the second fluid resistance portion. The first fluid resistance portion, the flow path between the fluid resistances, and the second fluid resistance portion are
It is arranged between the supply-side common liquid chamber leading to the plurality of individual liquid chambers and the individual liquid chambers.
The first fluid resistance portion is arranged on a plane different from that of the second fluid resistance portion.
The liquid discharge head according to claim 4. A liquid discharge unit comprising the liquid discharge head according to any one of claims 1 to 10 . A head tank that stores the liquid to be supplied to the liquid discharge head, a carriage on which the liquid discharge head is mounted, a supply mechanism that supplies the liquid to the liquid discharge head, a maintenance / recovery mechanism that maintains and recovers the liquid discharge head, and the liquid. The liquid discharge unit according to claim 11 , wherein at least one of the main scanning moving mechanisms for moving the discharge head in the main scanning direction is integrated with the liquid discharge head. A device for discharging a liquid, comprising the liquid discharge head according to any one of claims 1 to 10 and the liquid discharge unit according to claim 11 or 12 .

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