JP5862367B2 - Liquid ejecting head and method for driving liquid ejecting head - Google Patents

Description

  The present invention relates to a liquid ejecting head such as an ink jet recording apparatus and a method for driving the liquid ejecting head, and in particular, a liquid ejecting head that ejects a liquid containing a solid content such as a pigment from a nozzle and the driving of the liquid ejecting head. It is about the method.

  Examples of the liquid ejecting head that ejects (discharges) liquid droplets from the nozzle opening by causing pressure fluctuation in the pressure chamber include, for example, an ink jet recording head (hereinafter simply referred to as a recording head) used in an image recording apparatus such as a printer. Color material ejection heads used in the manufacture of color filters such as liquid crystal displays, electrode material ejection heads used in the formation of electrodes such as organic EL (Electro Luminescence) displays, FEDs (surface emitting displays), biochips (biochemistry) There are bio-organic matter ejecting heads and the like used for manufacturing the device.

  Some liquids used in the above liquid ejecting heads contain particles (solid content) in a solvent. For example, there is a pigment dispersion type ink (hereinafter referred to as pigment ink) in which a pigment is used as a coloring matter and the pigment is dispersed in an ink solvent. This pigment ink has a problem that the pigment settles (precipitates) when left for a long period of time. In particular, metallic pigments tend to settle. When the pigment settles, not only the pigment concentration in the ejected droplets may vary, but also the nozzle may be clogged.

  In order to solve such a problem, there has been proposed one in which a circulation channel is provided in a recording head and ink in a pressure chamber is circulated (see, for example, Patent Document 1). Thereby, the settled pigment can be stirred. Also, a method is known in which, when ink is not ejected from a nozzle for a certain period of time, pressure fluctuations (fine vibrations) that do not eject ink are generated in the pressure chamber, and the ink in the pressure chamber is agitated.

JP 2008-284739

  However, the recording head as in Patent Document 1 has a complicated structure because a circulation channel is provided in the recording head. In addition, it is necessary to separately prepare a drive source for circulating the ink. For this reason, this has led to an increase in cost and an increase in the size of the apparatus from the viewpoint of manufacturing the recording head. Further, in the method of applying a slight vibration in the pressure chamber, the ink in the pressure chamber cannot be sufficiently stirred. For example, an ink containing a relatively large diameter pigment could not be sufficiently stirred even if a slight vibration was applied.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a liquid ejecting head capable of easily stirring the liquid in the pressure chamber without providing a separate driving source, and the driving thereof. It is to provide a method.

The liquid ejecting head of the present invention has been proposed in order to achieve the above object. The liquid is filled in a pressure chamber communicating with the nozzle, and the liquid in the pressure chamber is converted into droplets from the nozzle by the operation of the pressure generating means. A liquid jet head capable of jetting,
The pressure generating means side of the pressure chamber is sealed with a diaphragm that deforms according to the operation of the pressure generating means with a transmission plate interposed therebetween,
The transmission plate has flexibility and has a hole through which the liquid can pass.

  According to the liquid ejecting head of the present invention, when the diaphragm is changed to the pressure generating means side, the liquid is caused to flow between the diaphragm and the transmission plate through the hole of the transmission plate, and then the diaphragm is When changing to the pressure chamber side, the liquid between the diaphragm and the transmission plate can flow into the pressure chamber through the hole of the transmission plate. The liquid in the pressure chamber can be agitated by the flow of the liquid from the holes of the transmission plate. Thereby, it is possible to prevent sedimentation of pigments and the like contained in the liquid in the pressure chamber without providing a separate drive source. Even when the pigment or the like has settled at the bottom of the pressure chamber, the settled pigment or the like can be stirred.

  In the above configuration, it is desirable that the transmission plate is configured to be less likely to be deformed from the pressure chamber side to the side opposite to the pressure chamber.

  According to this configuration, it is possible to positively allow the liquid to flow between the diaphragm and the transmission plate while suppressing the displacement of the pressure generating means during the liquid ejection.

  The said structure WHEREIN: It is desirable for the said permeation | transmission board to be comprised by the porosity on the pressure chamber side rather than the opposite side to a pressure chamber.

  According to this configuration, the diaphragm can be easily created.

According to another aspect of the invention, there is provided a liquid jet head driving method comprising:
Pressure generating means for causing a pressure fluctuation in the liquid in the pressure chamber;
A diaphragm that seals the pressure generating means side of the pressure chamber and deforms according to the operation of the pressure generating means;
A transmissive plate disposed on the pressure chamber side of the oscillating plate and laminated with the oscillating plate, having flexibility and having a hole through which the liquid can pass;
A method of driving a liquid jet head comprising:
An inflow step of causing the liquid to flow between the transmission plate and the vibration plate through the transmission plate by changing the vibration plate to the pressure generating means side;
A diffusion step of causing the vibration plate to change to the pressure chamber side, and causing the liquid between the transmission plate and the vibration plate to flow into the pressure chamber through the hole of the transmission plate. .

  According to the driving method of the liquid ejecting head, the liquid is caused to flow between the diaphragm and the transmission plate through the hole of the transmission plate by the inflow process, and then the vibration plate and the transmission plate through the hole of the transmission plate by the diffusion process. The liquid between the transmission plates can flow into the pressure chamber. The liquid in the pressure chamber can be agitated by the flow of the liquid from the holes of the transmission plate. Thereby, it is possible to prevent sedimentation of pigments and the like contained in the liquid in the pressure chamber without providing a separate drive source. Even when the pigment or the like has settled at the bottom of the pressure chamber, the settled pigment or the like can be stirred.

  In the above configuration, it is preferable that the diffusion step vibrates the diaphragm to such an extent that liquid is not ejected from the nozzle.

It is a perspective view of a printer. FIG. 2 is an exploded perspective view illustrating a configuration of a recording head. FIG. 3 is a cross-sectional view of a main part of the recording head. FIG. 2 is a block diagram illustrating an electrical configuration of a recording head. (A) is a wave form diagram explaining the structure of an ejection drive pulse, (b) is a wave form diagram explaining the structure of a spreading | diffusion drive pulse. It is a schematic diagram showing the ejection of the ink from a nozzle. It is a schematic diagram showing stirring of the ink in a pressure chamber. It is an expanded sectional view of the permeation board in other embodiments.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are made as preferred specific examples of the present invention. However, the scope of the present invention is not limited to the following description unless otherwise specified. However, the present invention is not limited to these embodiments. In the following description, an ink jet recording apparatus 1 (hereinafter referred to as a printer) will be described as an example of the liquid ejecting apparatus of the invention.

  FIG. 1 is a perspective view showing the configuration of the printer 1. The printer 1 is equipped with an ink jet recording head 2 (hereinafter referred to as a recording head) which is a kind of liquid ejecting head, and an ink cartridge 3 which is a kind of a liquid storing member that stores liquid ink therein. A carriage 4 is provided. A carriage moving mechanism 6 that reciprocates the carriage 4 in the paper width direction of the recording paper 5 (a type of recording medium and landing target), that is, the main scanning direction is provided at the rear of the carriage 4. Further, a platen 7 is provided below the recording head 2 at the time of recording operation with an interval. On the platen 7, the recording paper 5 is transported in the sub-scanning direction orthogonal to the main scanning direction by a transport mechanism 8 provided behind the printer 1.

  The carriage 4 is attached while being supported by a guide rod 9 installed in the main scanning direction, and moves in the main scanning direction along the guide rod 9 by the operation of the carriage moving mechanism 6. The position of the carriage 4 in the main scanning direction is detected by a linear encoder 10 which is a kind of position information detection means, and the detection signal, that is, an encoder pulse (a kind of position information) is sent to the control unit 41 of the printer 1 (see FIG. 4). ).

  In addition, a home position serving as a base point for scanning of the carriage 4 is set in an end area outside the recording area within the movement range of the carriage 4. A capping member 11 for sealing the nozzle surface (nozzle plate 17: see FIG. 3) of the recording head 2 and a wiper member 12 for wiping the nozzle surface are disposed at the home position in the present embodiment. The printer 1 is bi-directional between when the carriage 4 moves from the home position toward the opposite end and when the carriage 4 returns from the opposite end to the home position. So-called bidirectional recording is performed in which characters, images, and the like are recorded on the recording paper 5.

Next, the recording head 2 will be described.
FIG. 2 is an exploded perspective view showing the configuration of the recording head 2 of the present embodiment, and FIG. 3 is a cross-sectional view of the main part of the recording head 2. The recording head 2 in the present embodiment includes a flow path forming substrate 16, a nozzle plate 17, a transmission plate 18, a vibration plate 19, a piezoelectric element 20 (corresponding to pressure generating means in the present invention), a protective substrate 21, and the like. Configured.

  In this embodiment, the flow path forming substrate 16 is formed of a silicon single crystal substrate, and a plurality of pressure chambers 23 are arranged in parallel in the width direction (nozzle row direction). Each pressure chamber 23 is a hollow portion that is long in a direction orthogonal to the nozzle row, and penetrates the plate thickness direction of the flow path forming substrate 16. The upper part (the piezoelectric element 20 side) of the pressure chamber 23 is sealed with a vibration plate 19 with a transmission plate 18 interposed. That is, the transmission plate 18 is disposed so as to be laminated (overlapped) with the vibration plate 19 on the pressure chamber 23 side of the vibration plate 19. On the other hand, the lower part (bottom part) of the pressure chamber 23 is sealed by the nozzle plate 17.

  In addition, a communication portion 24 is formed in a region on the outer side in the longitudinal direction of the pressure chamber 23 of the flow path forming substrate 16. The communication portion 24 is in communication with each pressure chamber 23 via an ink supply path 25 provided for each pressure chamber 23. The ink supply path 25 is formed with a narrower width than the pressure chamber 23, and maintains a constant flow path resistance of the ink flowing into the pressure chamber 23 from the communication portion 24. The communication part 24 constitutes a part of a reservoir 26 that communicates with a common chamber 33 of the protective substrate 21 described later and serves as a common ink chamber for the pressure chambers 23.

  A nozzle plate 17 constituting the bottom of the pressure chamber 23 is joined to the lower side of the flow path forming substrate 16. The nozzle plate 17 is made of, for example, a silicon single crystal substrate having a thickness of about 0.1 to 1 mm, stainless steel, or the like, and a plurality of nozzles 29 are opened in a row corresponding to the pressure chambers 23. . This nozzle row is composed of, for example, 180 nozzles 29.

The transmission plate 18 is flexible and has a hole 30 through which the liquid can pass. For example, the transmission plate 18 of the present embodiment is formed of an elastic film made of silicon dioxide (SiO ₂ ) having a thickness of, for example, about 1.0 μm. A plurality of holes 30 penetrating in the plate thickness direction are formed in a portion corresponding to the pressure chamber 23 of the transmission plate 18 (a portion facing the piezoelectric element 20). It should be noted that the diameter of the hole 30 of the transmission plate 18 of the present embodiment is set to such a size that the flow path resistance to the ink that passes through the transmission plate 18 is sufficiently high. Accordingly, when the diaphragm 19 is displaced during the recording operation, the transmission plate 18 can be displaced while being in close contact with the diaphragm 19. The diaphragm 19 is a flexible plate that can be deformed according to the operation of the piezoelectric element 20. The diaphragm 19 of the present embodiment has, for example, an elastic film made of silicon dioxide (SiO ₂ ) having a thickness of, for example, about 1.0 μm and a thickness laminated on the elastic film of, for example, about 0.4 μm. And an insulator film made of zirconium oxide (ZrO ₂ ).

  A plurality of piezoelectric elements 20 are provided on the diaphragm 19 corresponding to the pressure chambers 23. The piezoelectric element 20 in the present embodiment is a flexural vibration mode vibrator, and is configured by sandwiching a piezoelectric body between a drive electrode and a common electrode (not shown). When a drive signal is applied to the drive electrode of the piezoelectric element 20, an electric field corresponding to the potential difference is generated between the drive electrode and the common electrode. This electric field is applied to the piezoelectric body, and the piezoelectric body is deformed according to the strength of the applied electric field.

  In addition, a protective substrate 21 having a piezoelectric element holding portion 32 that is a space of a size that does not inhibit the displacement in a region facing the piezoelectric element 20 on the surface of the flow path forming substrate 16 on the piezoelectric element 20 side. The transmission plate 18 and the diaphragm 19 are sandwiched. Since the piezoelectric element 20 is accommodated in the piezoelectric element holding portion 32, the piezoelectric element 20 is protected in a state hardly affected by the external environment. Further, as shown in FIG. 2, the protective substrate 21 is provided with a common chamber 33 in a region corresponding to the communication portion 24 of the flow path forming substrate 16. The common chamber 33 penetrates the protective substrate 21 in the thickness direction and is provided along the direction in which the pressure chambers 23 are juxtaposed. As described above, the common chamber 33 communicates with the communication portion 24 of the flow path forming substrate 16 and is connected to each common chamber 33. A reservoir 26 serving as a common ink chamber for the pressure chamber 23 is configured.

  Further, a compliance substrate 36 including a sealing film 34 and a fixing plate 35 is bonded onto the protective substrate 21. The sealing film 34 is made of a material having low rigidity and flexibility (for example, a polyphenylene sulfide film having a thickness of 6 μm), and one surface of the common chamber 33 is sealed by the sealing film 34. The fixing plate 35 is made of a hard material such as metal (for example, stainless steel having a thickness of 30 μm). Since the region of the fixing plate 35 facing the reservoir 26 is a fixing plate opening 37 that is completely removed in the thickness direction, only one surface of the reservoir 26 is made of a flexible sealing film 34. It is sealed.

  Next, the electrical configuration of the printer 1 will be described. FIG. 4 is a block diagram illustrating the electrical configuration of the printer 1. The printer 1 in this embodiment includes a transport mechanism 8, a carriage moving mechanism 6, a linear encoder 10, a recording head 2, and a control unit 41. The external device 40 is an electronic device that handles images, such as a computer or a digital camera. The external device 40 is communicably connected to the control unit 41 of the printer 1, and in order for the printer 1 to print an image or text on a recording medium such as the recording paper 5, print data corresponding to the image or the like is transmitted to the printer. 1 to send.

  The control unit 41 is a control unit for controlling each unit of the printer 1, and includes an interface (I / F) unit 44, a CPU 45, a storage unit 46, and a drive signal generation unit 47. The interface unit 44 transmits / receives data to / from the printer 1 such as receiving print data or a print command transmitted from the external device 40 to the printer 1 or transmitting status information of the printer 1 to the external device 40. . The CPU 45 is an arithmetic processing device for controlling the entire printer 1. The memory | storage part 46 is an element which memorize | stores the data used for the program and various control of CPU45, and contains ROM, RAM, and NVRAM (nonvolatile memory element). The CPU 45 controls each unit according to a program stored in the storage unit 46.

  Further, the CPU 45 functions as a timing pulse generating unit that generates a timing pulse from the encoder pulse output from the linear encoder 10. Then, the CPU 45 controls transfer of print data, generation of a drive signal by the drive signal generation unit 47, and the like in synchronization with this timing pulse. Further, the CPU 45 generates a timing signal such as a latch signal based on the timing pulse and outputs the timing signal to the head control unit 43 of the recording head 2. The head control unit 43 performs drive signal application control on the piezoelectric element 20 of the recording head 2 based on a head control signal (print data, timing signal, etc.) from the control unit 41.

  The drive signal generation unit 47 generates an analog voltage signal based on waveform data relating to the waveform of the drive signal. The drive signal generator 47 amplifies the voltage signal to generate a drive signal. This drive signal includes at least one of the ejection drive pulse DP shown in FIG. 5 (a) and the diffusion drive pulse VP shown in FIG. 5 (b) within a unit period that is a generation repetition cycle of the drive signal. A series of signals including one or more. Here, the ejection drive pulse DP is for causing the piezoelectric element 20 to perform a predetermined operation in order to perform a recording operation of ejecting ink from the nozzles 29 of the recording head 2. Further, the diffusion drive pulse VP is for causing the piezoelectric element 20 to perform a predetermined operation in order to perform the stirring operation of stirring the ink in the pressure chamber 23. In the present embodiment, the configuration in which the ejection drive pulse DP and the diffusion drive pulse VP are included in the same drive signal is illustrated, but the present invention is not limited to this, and configurations that are included in different drive signals may be employed. It is.

  FIG. 5A is a waveform diagram showing an example of the configuration of the ejection drive pulse DP included in the drive signal during the recording operation. In FIG. 5, the vertical axis represents potential and the horizontal axis represents time. Further, as shown in FIG. 5, the ejection driving pulse DP and the diffusion driving pulse VP of the present embodiment have a positive polarity on average.

  The injection drive pulse DP includes an expansion element dp1, an expansion maintenance element dp2, a contraction element dp3, a contraction maintenance (vibration hold) element dp4, and a return element dp5. The expansion element dp1 expands the pressure chamber 23 by changing the potential from the reference potential (intermediate potential) Vb to the minimum potential (minimum voltage) Vmin in the negative direction. The expansion maintaining element dp2 maintains the minimum potential Vmin for a certain time. The contraction element dp3 rapidly contracts the pressure chamber 23 by changing the potential from the minimum potential Vmin to the maximum potential (maximum voltage) Vmax on the positive side. The contraction maintaining element dp4 maintains the minimum potential Vmax for a certain time. The return element dp5 returns the potential from the minimum potential Vmax to the reference potential Vb.

  FIG. 5B is a waveform diagram showing an example of the configuration of the diffusion drive pulse VP included in the drive signal during the stirring operation. The diffusion drive pulse VP includes an expansion element vp1, an expansion maintenance element vp2, and a contraction element vp3. The expansion element vp1 changes its potential in the negative direction from the reference potential (intermediate potential) Vb to the minimum potential (minimum voltage) Vmin ′ and gently deflects the diaphragm 19. The expansion maintaining element vp2 maintains the minimum potential Vmin ′ for a certain time. The contraction element vp3 changes the potential from the minimum potential Vmin ′ to the reference potential Vb on the plus side, and gently changes the diaphragm 19. Note that the application time of the expansion element vp1 is set to a time that allows liquid to flow between the diaphragm 19 and the transmission plate 18 by deforming only the diaphragm 19 from the close contact state of the transmission plate 18 and the vibration plate 19. ing. For example, the potential change amount per unit time of the expansion element vp1 is set to be sufficiently smaller than the potential change amount of the expansion element dp1 of the ejection drive pulse DP. The application time of the expansion maintaining element vp2 is set to a time sufficient for the transmission plate 18 to be displaced near the reference position (position corresponding to the reference potential Vb). Further, the application time of the contraction element vp3 is set to such a time that the vibration plate 19 is gently displaced and ink is not ejected from the nozzles 29. The amount of potential change per unit time of the contraction element vp3 is set to be sufficiently smaller than the amount of potential change of the contraction element dp3 of the ejection drive pulse DP.

  Next, the operation when the ejection drive pulse DP and the diffusion drive pulse VP are applied to the piezoelectric element 20 will be described. FIG. 6 is a schematic diagram illustrating a recording operation in which the ejection drive pulse DP is applied to the piezoelectric element 20 and ink is ejected from the nozzles 29. FIG. 7 is a schematic diagram showing a diffusion operation in which the diffusion drive pulse VP is applied to the piezoelectric element 20 and the ink in the pressure chamber 23 is agitated.

  First, the recording operation will be described. When the expansion element dp1 of the ejection drive pulse DP is applied to the piezoelectric element 20, the piezoelectric element 20 bends to the opposite side to the pressure chamber 23, and accordingly, the diaphragm 19 is minimized from the reference position corresponding to the reference potential Vb. It is displaced (varied) to the highest position on the piezoelectric element 20 side corresponding to the potential Vmin. As the vibration plate 19 is displaced, the transmission plate 18 is also displaced to the highest position on the piezoelectric element 20 side, as shown in FIG. Here, since the flow path resistance of the ink passing through the transmission plate 18 is set to be sufficiently high, the ink vibrates through the hole 30 of the transmission plate 18 at the displacement speed of the piezoelectric element 20 by the expansion element dp1. The diaphragm 19 is displaced in a state of being in close contact with the diaphragm 19 before flowing between the plate 19 and the transmission plate 18. As a result, the volume of the pressure chamber 23 expands to the maximum volume, ink flows from the reservoir 26 into the pressure chamber 23, and the meniscus exposed to the nozzle 29 is drawn into the pressure chamber 23 side.

  The expansion state of the pressure chamber 23 is maintained for a short time during the application period of the expansion maintaining element dp2. When the contraction element dp3 is applied to the piezoelectric element 20 subsequent to the expansion maintaining element dp2, the piezoelectric element 20 bends toward the pressure chamber 23, whereby the diaphragm 19 corresponds to the maximum potential Vmax from the highest position. Displaces rapidly to the lowest position on the pressure chamber 23 side. As the vibration plate 19 is displaced, the transmission plate 18 is also displaced to the lowest position on the piezoelectric element 20 side, as shown in FIG. 6B. Thereby, the volume of the pressure chamber 23 contracts rapidly from the maximum volume to the minimum volume. The ink in the pressure chamber 23 is pressurized by the rapid contraction of the pressure chamber 23, and thereby, several pl to several tens pl of ink is ejected from the nozzle 29. The contraction state of the pressure chamber 23 is maintained for a short time over the application period of the contraction maintaining element dp4. Thereafter, the damping element dp5 is applied to the piezoelectric element 20, the diaphragm 19 and the transmission plate 18 are displaced to the reference position, and the pressure chamber 23 is changed from the minimum volume corresponding to the maximum potential Vmax to the reference volume corresponding to the reference potential Vb. Return until.

  Next, the stirring operation will be described. When the expansion element vp1 of the stirring drive pulse VP is applied to the piezoelectric element 20, the piezoelectric element 20 bends to the opposite side to the pressure chamber 23, and accordingly, the central portion of the diaphragm 19 corresponds to the reference potential Vb. The pressure chamber 23 is displaced outward from the reference position to a position corresponding to the minimum potential Vmin ′. Since the displacement of the diaphragm 19 is slower than that due to the expansion element dp1 of the ejection drive pulse DP, the transmission plate 18 hardly follows the displacement of the diaphragm 19. Therefore, as shown in FIG. 7A, ink flows between the diaphragm 19 and the transmission plate 18 through the holes 30 of the transmission plate 18 (inflow process). In addition, ink flows from the reservoir 26 into the pressure chamber 23 along with the displacement of the vibration plate 19.

  The state in which the diaphragm 19 is displaced is maintained over the application period of the expansion maintaining element dp2. Here, since the expansion maintaining element dp2 is maintained for a sufficient time, even if the transmission plate 18 follows the vibration plate 19 and is displaced to the piezoelectric element 20 side, the transmission plate 18 thereafter has its own restoring force and It is possible to return to the reference position away from the diaphragm 19 by the action of gravity. The ink that has flowed in is stored in a space formed between the diaphragm 19 and the transmission plate 18. When the contraction element dp3 is applied to the piezoelectric element 20 subsequent to the expansion maintaining element dp2, the piezoelectric element 20 bends to the pressure chamber 23 side, whereby the diaphragm 19 is moved to the above-described position as shown in FIG. It is gradually displaced from the highest position to the reference position. Due to the displacement of the vibration plate 19, the ink stored in the space between the vibration plate 19 and the transmission plate 18 is ejected (inflowed) to the pressure chamber 23 side through the hole 30 of the transmission plate 18 (diffusion process). ). By this ejection, as shown by the arrow in FIG. 7B, it is possible to create an ink flow in a direction perpendicular to the ink flow during the recording operation (the flow from the ink supply path 25 toward the nozzle 29). . By this flow, the ink in the pressure chamber 23 can be stirred. In the contraction element dp3, since the vibration plate 19 is gently displaced, no ink is ejected from the nozzles 29.

  As described above, when the vibration plate 19 is changed to the piezoelectric element 20 side, ink is caused to flow between the vibration plate 19 and the transmission plate 18 through the hole 30 of the transmission plate 18, and then the vibration plate 19 is moved. When the pressure chamber 23 is changed, the ink between the diaphragm 19 and the transmission plate 18 can flow into the pressure chamber 23 through the hole 30 of the transmission plate 18. The ink in the pressure chamber 23 can be agitated by the flow of ink from the hole 30 of the transmission plate 18. Thereby, it is possible to prevent sedimentation of pigments or the like contained in the ink into the pressure chamber 23 without providing a separate drive source. Even when the pigment or the like has settled at the bottom of the pressure chamber 23, the settled pigment or the like can be stirred.

  By the way, the transmission plate described above can adopt a configuration that is less likely to be deformed to the opposite side (piezoelectric element 20 side) from the pressure chamber 23 side than the pressure chamber 23 side. For example, in the transmission plate 18 ′ shown in FIG. 8, the groove 49 along the direction (nozzle row direction) perpendicular to the longitudinal direction of the pressure chamber 23 is formed on the surface on the pressure chamber 23 side. There are multiple rows in the direction. In other words, the transmission plate 18 ′ has a plurality of rows of ridges 51 (elongated rectangular parallelepiped blocks) in a direction perpendicular to the longitudinal direction of the pressure chamber 23 on the surface of the transmission substrate 50, which is a base material, on the pressure chamber 23 side. It is installed. In this way, even when the piezoelectric element 20 is driven and the diaphragm 19 is bent toward the piezoelectric element 20 (in the direction of the arrow shown in FIG. 8) during the stirring operation, the transmission plate 18 ′ moves to the diaphragm 19. It is possible to suppress the follow-up bending. Specifically, when the transmission plate 18 ′ follows the vibration plate 19 and tries to bend toward the piezoelectric element 20 side, the adjacent flanges 51 come into contact with each other, so that the transmission plate 18 ′ moves toward the piezoelectric element 20 side. This makes it difficult to deform. For this reason, it is possible to positively allow liquid to flow between the diaphragm 19 and the transmission plate 18 '. On the other hand, when the transmission plate 18 ′ is displaced toward the pressure chamber 23, the adjacent flanges 51 do not come into contact with each other, so that the transmissive plate 18 ′ is easily deformed as compared with the piezoelectric element 20 side. Inhibiting the displacement of 19 is suppressed. In addition, hole 30 'of this embodiment is opened inside the groove | channel 49 (bottom part of the groove | channel 49).

  Such a transmission plate is not limited to the configuration described above. For example, a permeable membrane having a two-layer structure including a dense layer having a low porosity on the piezoelectric element side and a porous layer having a high porosity on the pressure chamber side can be used. In this way, if the transmission plate is bent toward the piezoelectric element, the gap between the porous layers is filled and the rigidity is increased, so that the transmission plate is hardly deformed. Thereby, a liquid can be actively made to flow between a diaphragm and a permeation | transmission board. On the other hand, when the transmission plate is bent toward the pressure chamber, the gap between the porous layers is not filled, so that the transmission plate is relatively easily deformed. In other words, a transmission plate having any configuration may be used as long as the porosity on the pressure chamber side is higher than that on the side opposite to the pressure chamber. In addition, the hole penetrating in the plate thickness direction is opened at a predetermined position.

  In the above embodiment, the so-called flexural vibration type piezoelectric element 20 is exemplified as the pressure generating means. However, the present invention is not limited to this, and for example, a so-called longitudinal vibration type piezoelectric element can be employed. In this case, with respect to the waveforms of the drive signals (ejection drive pulse DP and diffusion drive pulse VP) illustrated in FIG. In addition, the pressure generating means is not limited to the piezoelectric element, and various pressure generating means such as a heat generating element that generates bubbles in the pressure chamber and an electrostatic actuator that changes the volume of the pressure chamber using electrostatic force are used. The present invention can also be applied.

  The present invention is not limited to a printer as long as it is a liquid ejecting head of a liquid ejecting apparatus capable of controlling the ejection of liquid using a pressure generating means, and various ink jet recording apparatuses such as a plotter, a facsimile machine, and a copying machine. It can also be applied to liquid ejecting apparatuses other than recording apparatuses, for example, liquid ejecting heads used in display manufacturing apparatuses, electrode manufacturing apparatuses, chip manufacturing apparatuses, and the like. In the display manufacturing apparatus, a solution of each color material of R (Red), G (Green), and B (Blue) is ejected from the color material ejecting head. Moreover, in an electrode manufacturing apparatus, a liquid electrode material is ejected from an electrode material ejection head. In the chip manufacturing apparatus, a bioorganic solution is ejected from a bioorganic ejecting head.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Recording head, 15 ... Flow path formation board | substrate, 17 ... Nozzle plate, 18 ... Transmission plate, 19 ... Vibration plate, 20 ... Piezoelectric element, 21 ... Protection board, 23 ... Pressure chamber, 24 ... Communication part , 25 ... Ink supply path, 26 ... Reservoir, 29 ... Nozzle, 30 ... Hole, 32 ... Piezoelectric element holder, 33 ... Common chamber, 34 ... Sealing film, 35 ... Fixed plate, 36 ... Compliance substrate, 37 ... Fixed Plate opening, 40 ... external device, 41 ... control unit, 43 ... head control unit, 44 ... interface unit, 45 ... CPU, 46 ... storage unit, 47 ... drive signal generation unit, 49 ... groove, 50 ... transparent substrate, 51 ... 畝

Claims (5)

A liquid ejecting head capable of filling a liquid in a pressure chamber communicating with a nozzle and ejecting the liquid in the pressure chamber as droplets from the nozzle by operation of a pressure generating unit;
The pressure generating means side of the pressure chamber is sealed with a diaphragm that deforms according to the operation of the pressure generating means with a transmission plate interposed therebetween,
The liquid ejecting head, wherein the transmission plate has flexibility and has a hole through which the liquid can pass.   The liquid ejecting head according to claim 1, wherein the transmission plate is configured to be less likely to be deformed from the pressure chamber side to the side opposite to the pressure chamber.   The liquid ejecting head according to claim 2, wherein the transmission plate is configured to have a higher porosity on the pressure chamber side than on the side opposite to the pressure chamber. A pressure chamber communicating with the nozzle;
Pressure generating means for causing a pressure fluctuation in the liquid in the pressure chamber;
A diaphragm that seals the pressure generating means side of the pressure chamber and deforms according to the operation of the pressure generating means;
A transmissive plate disposed on the pressure chamber side of the oscillating plate and laminated with the oscillating plate, having flexibility and having a hole through which the liquid can pass;
A method of driving a liquid jet head comprising:
An inflow step of causing the liquid to flow between the transmission plate and the vibration plate through the transmission plate by changing the vibration plate to the pressure generating means side;
A diffusion step of causing the vibration plate to change to the pressure chamber side, and causing the liquid between the transmission plate and the vibration plate to flow into the pressure chamber through the hole of the transmission plate. A method for driving a liquid jet head.   The method of driving a liquid ejecting head according to claim 4, wherein in the diffusing step, the vibration plate is vibrated to such an extent that liquid is not ejected from the nozzle.

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