JP4756225B2 - RECORDING HEAD AND INKJET RECORDING DEVICE HAVING THE SAME - Google Patents

Description

  The present invention relates to a recording head and an inkjet recording apparatus including the recording head, and more particularly to a recording head capable of recording a high-quality image at high speed and with high reliability and an inkjet recording apparatus including the recording head.

  In order to record high-quality images at high speed and with high reliability using a multi-nozzle on-demand ink jet recording head that integrates a large number of nozzles, the ejection speed of ink droplets from the nozzles must be increased. It is particularly important that ink droplets can be ejected stably up to a high frequency.

  As a nozzle structure for increasing the discharge speed of ink droplets and enabling stable discharge to a high frequency, as disclosed in Patent Document 1, one surface of an ink pressurizing chamber having a nozzle hole as an opening is used. There is known a so-called push-type piezoelectric element system which is constituted by a diaphragm and presses the diaphragm by longitudinal vibration of a rod-shaped piezoelectric element to reduce the volume of an ink pressurizing chamber and eject ink droplets.

  The rod-shaped piezoelectric elements used in this push-type piezoelectric element system are arranged in at least the same number as the number of nozzles, and the opposite side of the rod-shaped piezoelectric element to the diaphragm is fixed to the piezoelectric element support substrate. The piezoelectric element support substrate is bonded and fixed to the head housing.

  In the recording head having such a structure, when the piezoelectric element is driven according to the recording signal input data, not only the diaphragm vibrates, but also the longitudinal vibration of the piezoelectric element is transmitted to the piezoelectric element supporting substrate, the head housing, etc. There is a problem that the discharge characteristics tend to be unstable.

  Further, when the driven piezoelectric element vibrates, the nozzle corresponding to the piezoelectric element is also affected, and there is a so-called crosstalk problem that the ink droplet ejection characteristics are changed.

  In order to avoid such a problem, Patent Document 2 discloses a structure in which a piezoelectric element support substrate is formed of a relatively high-rigidity member and receives vibrations of the piezoelectric element.

  In Patent Document 3, the influence of vibration of a piezoelectric element to which a drive pulse for ejecting ink droplets is applied is compensated by exciting at least one other piezoelectric element, and mutual interference between nozzle units. A method to alleviate this problem has been proposed.

JP-A-6-270403 JP 2002-361868 A Japanese Patent Laid-Open No. 9-99554

  However, the method of optimizing the rigidity of the piezoelectric element support substrate as disclosed in Patent Document 2 and the effect of the vibration of the piezoelectric vibrator as disclosed in Patent Document 3 are compensated by exciting other vibrators. Even when using this method, when ejecting ink droplets, each part of the head or the entire head vibrates abnormally in a specific frequency range and ink mist is generated, or the ink ejection direction deviates from a predetermined direction, or from the nozzle hole. There is a problem that the ink protrudes and wets around the nozzle hole, resulting in non-ejection.

  In addition, even when ejected normally, there is a problem that ink droplet ejection characteristics fluctuate due to so-called crosstalk. Such a problem becomes more prominent in a push-type on-demand recording head when a large number of nozzles are integrated and the head is lengthened. In order to enable high-viscosity ink to be ejected, a piezoelectric element support substrate or the like is used. This is a particularly serious problem when the resonance frequency of each part decreases or the excitation force increases.

  In addition, in the conventional recording head driving apparatus, a control element such as a switching element is provided for each piezoelectric element in order to selectively apply a driving pulse to the piezoelectric element corresponding to each nozzle, and each control element is connected to the piezoelectric element. It was necessary to provide a flexible cable. For this reason, in a recording head in which a large number of nozzles are integrated at a high density, the number of the control elements increases, resulting in an increase in cost, and the number of flexible cables increases, resulting in an increase in cost and mounting problems. It was.

  An object of the present invention is to provide a recording head that solves the above-described conventional problems and an ink jet recording apparatus including the recording head.

  Specifically, an object of the present invention is to provide a recording head capable of always discharging ink droplets stably without abnormal vibration of each part and each member of the recording head, and an ink jet recording apparatus including the recording head. An object of the present invention is to provide a recording head and an ink jet recording apparatus which are inexpensive and easy to mount by reducing the number of switching elements for selectively driving piezoelectric elements.

In order to achieve the above object, the present invention attaches a piezoelectric element to a diaphragm that forms a part of an ink pressurizing chamber, and deforms the diaphragm according to the expansion and contraction of the piezoelectric element, whereby ink liquid is discharged from the nozzle hole. the nozzle element so as to eject an ink jet recording head formed by arranging a plurality, first and second nozzle elements adjacent the vibration before Symbol diaphragm of the first nozzle element, said second nozzle A drive signal is applied to the piezoelectric elements of the first and second nozzle elements so that the vibration of the element diaphragm is reversed , and the drive signal source for generating the drive signal is negative A signal source for generating an A phase driving pulse for generating a positive pulse next to the pulse and a B phase driving pulse for generating a negative pulse next to the positive pulse, When the A phase driving pulse is applied to the piezoelectric element of the second nozzle element, the ink liquid is ejected from the first nozzle element, and when the B phase driving pulse is applied, the ink liquid is ejected from the second nozzle element. having a particular one of the characteristics was.

Another feature of the present invention is that the adjacent first and second nozzle elements have piezoelectric elements whose polarization polarities are opposite to each other .

  Another feature of the present invention is that each of the adjacent piezoelectric elements of the first and second nozzle elements has a common electrode and an individual electrode, and the common electrode serves as a drive signal source for driving the piezoelectric element. The individual electrodes are connected to a common switching element, and the driving signal of the driving signal source is applied to the piezoelectric elements of the first and second nozzle elements in accordance with opening and closing of the switching element. There is.

  Another feature of the present invention is that the individual electrodes of the piezoelectric elements of the first and second nozzle elements are electrically connected by wiring on the piezoelectric element support substrate and then connected to the switching element. It is in.

  Another feature of the present invention is that the ink pressurizing chamber of the nozzle element has an ink inlet port for allowing ink to flow into the ink pressurizing chamber from a common ink chamber, and the ink inlet port is The sectional area on the ink pressurizing chamber side is made smaller than the sectional area on the common ink chamber side.

Another feature of the present invention is that the nozzle hole is formed in an orifice plate, and the vicinity of the opening of the nozzle hole is made lower than the surface of the orifice plate to form a step, thereby forming an ink reservoir.

  According to the present invention, when the piezoelectric vibrators of the adjacent first and second nozzle elements are driven, the vibrations of the diaphragms of the respective nozzle elements are in opposite directions, so that other parts, that is, other nozzle elements The excitation force to common members such as the piezoelectric element support substrate and the housing is suppressed, abnormal vibration is suppressed, abnormal meniscus vibration is eliminated, crosstalk is reduced, and stable ink ejection is possible. There is an effect.

  For this reason, since ink droplets having the same ink ejection speed and weight can be ejected from each nozzle with high reliability, an ink jet recording apparatus capable of recording high-quality images at high speed and with high reliability can be provided.

  In addition, since the adjacent first and second nozzle elements share the switching element, the number of switching elements can be halved, and the number of wirings of cables connecting the recording head and the recording head driving device can also be halved. As a result, it is advantageous for downsizing and cost reduction of the recording apparatus.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 shows an apparatus configuration of an ink jet recording apparatus according to the present invention, which includes a recording head 10 and a recording head driving apparatus 20. First, an embodiment of the recording head 10 will be described, and then the recording head driving device 20 will be described. Subsequently, the ink droplet ejection operation of the recording apparatus of the present invention and other embodiments of the recording head will be described in order.

(1) Recording head 10
As shown in FIG. 1, the recording head 10 according to the present invention includes an ink flow path unit 101, a head housing 102 that holds the unit 101, and a piezoelectric element unit 103. Among these, the ink flow path unit 101 includes an orifice plate 130 in which nozzle holes 131 are provided in a row, an ink flow path forming plate 142, and a diaphragm forming plate 122 in which the diaphragm 120 is formed, as shown in FIG. They are formed by sticking with an adhesive in order or joining by an anodic bonding method or the like.

  By the ink flow path unit 101, the ink pressurizing chamber 140 having the nozzle hole 131 as the open end, the ink inlet 145 for guiding ink to the ink pressurizing chamber 140, and the common ink chamber for supplying ink to the ink inlet 145 150 is configured. In addition, by attaching the diaphragm forming plate 122, at least one wall surface of the ink pressurizing chamber 140 is formed by the diaphragm 120. The tip of the rod-shaped piezoelectric element 110 of the piezoelectric element unit 103 is abutted against the surface of the diaphragm 120 opposite to the ink pressurizing chamber 140 and is bonded to the diaphragm 120 with an adhesive.

  The piezoelectric element unit 103 is configured by fixing a plurality of rod-shaped piezoelectric elements 110 to a piezoelectric element supporting substrate 113 in a comb shape. The rod-shaped piezoelectric element 110 has a structure in which a plurality of layered piezoelectric elements 111 are stacked via layered electrodes 112. Every other layered electrode 112 is connected to a common electrode 1121 and an individual electrode 1122 formed on the side surface of the rod-shaped piezoelectric element 110. The common electrode 1121 and the individual electrode 1121 are connected to the common electrode 1121 ′ and the individual electrode 1122 ′ formed on the upper surface of the piezoelectric element support substrate 113, respectively. Further, two individual electrodes 1121 ′ are connected as one set to the flexible cable terminal 161 of the flexible cable 160.

  As shown in FIG. 1, columnar piezoelectric element support substrate fixing portions 114 are provided on the piezoelectric element support substrates 113 located at both ends in the arrangement direction of the piezoelectric elements 110, and the bottom surface of the fixing portion 114 is an ink flow path. It is fixed to the unit 101 with an adhesive or the like. On the other hand, since the ink flow path unit 101 is adhesively fixed to the head housing 102 in the vicinity of the adhesive fixing portion, the bottom surface of the piezoelectric element support substrate fixing portion 114 is fixed to the head housing 102. .

  In the recording head 10 configured as described above, the orifice plate 130 has n nozzle holes 131 formed in rows at a predetermined pitch as shown in FIG. 3A. N nozzle elements (# 1, # 2,... N) are formed by the ink pressurizing chamber 140 and the comb-like rod-shaped piezoelectric element 110. Ink droplets indicated by 30 are ejected from each nozzle element and recorded on the recording medium 40.

  In the present invention, two adjacent rod-shaped piezoelectric elements 110 are preset in such a manner that they are polarized with opposite polarities, and the magnitudes of polarization are substantially the same.

  Accordingly, when the first nozzle element # 1 and the second nozzle element # 2 in FIG. 3A are viewed, the piezoelectric element between the common electrode 1121 and the individual electrode 1122 of the nozzle element # 1 is not illustrated. On the other hand, the polarization remains in the direction, and between the common electrode 1121 and the individual electrode 1122 of the nozzle element # 2, the polarization of approximately the same size as the nozzle element # 1 remains in the reverse direction as shown in the figure. Therefore, when the same voltage is applied to both elements # 1 and # 2, the piezoelectric elements of nozzle element # 1 and nozzle element # 2 are displaced by substantially the same amount in opposite directions.

(2) Recording head driving device 20
As shown in FIG. 1, the recording head driving device 20 includes a recording data signal generating circuit 302, a piezoelectric element driving data signal generating circuit 303, a piezoelectric element driving switching circuit 304, a timing signal generating circuit 301, and an A & B phase piezoelectric element driving pulse waveform generation. A circuit 305 is provided.

  The recording data signal generation circuit 302 generates a recording data signal based on recording signal input data sent from a host device (for example, a personal computer) (not shown). The piezoelectric element drive data signal creation circuit 303 creates a piezoelectric element drive data signal based on the recording data signal and the timing signal from the timing signal generation circuit 301.

  The piezoelectric element drive data signal creation circuit 303 includes an odd-numbered nozzle piezoelectric element drive data signal circuit for driving the odd-numbered nozzles of the recording head and an even-numbered nozzle piezoelectric element drive for driving the even-numbered nozzles. A data signal circuit is provided. Adjacent odd-numbered nozzle elements and even-numbered nozzle elements are sequentially grouped every two, and the two piezoelectric elements 110 of each group are connected in common to one switching element of the piezoelectric element driving switching circuit 304. Is done.

  That is, as shown in FIG. 3A, the first nozzle element # 1 and the second nozzle element # 2 are set as one set, and the individual electrode 1122 of each piezoelectric element 110 is a switch of the piezoelectric element drive switching circuit 304. Connected to SW1. Then, the third nozzle element # 3 and the fourth nozzle element # 4 are connected to the individual electrode 1122 or the switch SW2 of each piezoelectric element 110 as a set. Similarly, two adjacent nozzle elements are set as one set, and the individual electrodes 1122 of the piezoelectric elements 110 belonging to the set are connected to different switches. Also, the common electrodes 1121 of the piezoelectric elements 110 of all the nozzle elements # 1, # 2, # 3,... #N are connected in common.

  On the other hand, the A & B phase piezoelectric element drive pulse waveform generation circuit 305 generates an A phase drive pulse and a B phase drive pulse as shown in FIG. 4A, and these pulses are applied to the piezoelectric element 110 via the common electrode 1121. Applied. The switching elements SW1 and SW2 are operated by a switching element drive circuit 3042 controlled by a piezoelectric element drive data signal. For example, when the switch SW1 is turned on, the adjacent two nozzle elements # 1 and # 2 have a phase A phase. And B-phase piezoelectric element drive pulses are applied simultaneously.

(3) Ink Drop Discharge Operation Next, the ink drop discharge operation of the ink jet recording apparatus according to the present invention will be described with reference to FIGS. 3-1, 3-2, 3-3 and FIG.

  4A shows the output of the A & B phase piezoelectric element drive pulse waveform generation circuit 305, FIG. 4B shows the drive pulse of the switching element SW1, and FIG. 4B shows the waveforms of the drive pulse of the switching element SW2.

  A pulse for driving the piezoelectric element 110 includes an A phase driving pulse and a B phase driving pulse. In the A phase, the voltage changes from 0 level to −V in the period T1, and after −V is maintained for a predetermined time T2, the voltage is increased from −V to + V in the period T3, and + V is maintained for a predetermined time T4, and then in the period T5. The waveform returns from + V to 0 level. In contrast to the A phase, the B phase first rises from 0 level to + V at the time T1, maintains + V for a predetermined time T2, then changes from + V to -V in a period T3, and maintains -V for a predetermined time T4. The waveform returns from −V to 0 level in the later period T5.

  When the drive pulse level of (b1) and (b2) is high, the switches SW1 and SW2 are turned on, and when the drive pulse level is low, the switches SW1 and SW2 are driven to turn off.

  In FIG. 4, since the switching element SW1 is controlled to be turned on by the signal (b1) and the switching element SW2 is turned off by the signal (b2) at time T (1) -A, as shown in FIG. The contact of SW1 is closed and the contact of SW2 is opened. Therefore, the individual electrodes 1122 of the piezoelectric elements 110 of the nozzle element # 1 and the nozzle element # 2 are grounded via the switching element SW1.

  On the other hand, since the drive pulse voltage shown in FIG. 4A is applied to the common electrode 1121 of the piezoelectric element 110, the nozzle element # 1 and the nozzle element # 2 are driven with the A-phase drive pulse voltage. .

  For this reason, the piezoelectric element 110 of the nozzle element # 1 gradually contracts in the period T1, maintains the contracted state in the period T2, rapidly expands in the period T3, maintains the expanded state in the period T4, and gradually returns to the original state in the period T5. Return. The volume of the ink pressurizing chamber 140 changes due to such expansion and contraction of the piezoelectric element.

Nozzle elements # 1 in Figure 3-1 of the time _{t 1} state, that shows a state in which the compression element 110 is increasing rapidly. By the expansion of the piezoelectric element 110 and the volume contraction of the ink pressurizing chamber, the ink droplet 30 is ejected from the nozzle hole 131 of the nozzle element # 1. On the other hand, the piezoelectric element 110 of the nozzle element # 2 has a polarization direction opposite to that of the piezoelectric element 110 of the nozzle element # 1, and is set to have approximately the same magnitude of polarization. The expansion and contraction movements of the piezoelectric element 110 and the ink pressurizing chamber 140 of the element # 2 are completely opposite to those of the nozzle element # 1. Therefore, in the period T3, the volume of the pressurizing chamber 140 increases, and ink is supplied from the common ink chamber 150 to the ink pressurizing chamber 140 through the ink inlet 145.

  For this reason, even if the A phase driving pulse of FIG. 4A is applied, no ink droplet is ejected from the nozzle hole 131 of the nozzle element # 2. Conversely, the meniscus is drawn from the nozzle hole 131 to the ink pressurizing chamber 140 side. However, by setting the ink inlet 145 to be larger, for example, bubbles can be prevented from being sucked into the ink pressurizing chamber 140 from the nozzle hole 131. In addition, since SW2 is OFF in nozzle elements # 3 and # 4, the driving pulse voltage shown in FIG. 4A is not applied, and the piezoelectric element 110 does not expand and contract and remains stopped.

  Next, in the period T (1) -B, the switching element SW1 is turned off by the signal in FIG. 4B1, and SW2 is controlled to be turned on by the signal in FIG. 4B2. Therefore, as shown in FIG. 3-2, the contact of the switching element SW1 is opened, and the contact of SW2 is closed. For this reason, the individual electrodes 1122 of the piezoelectric elements 110 of the nozzle element # 3 and the nozzle element # 4 are grounded via the switching element SW2.

Since the drive pulse voltage shown in FIG. 4A is applied to the common electrode 1121 of the piezoelectric element 110, the nozzle element # 3 and the nozzle element # 4 are driven by the B phase drive pulse. Thus piezoelectric elements 110 of the nozzle element # 4 is extended in time t _2, the the volume of the ink pressure chamber 140 becomes contracted state, the ink droplet 30 is ejected. On the other hand the piezoelectric element 110 of the nozzle element # 3 at time t ₂ to polarized in opposite directions to increase the volume of the ink pressure chamber 140, a state in which ink is sucked into the ink pressure chamber 140 from the common ink chamber 150 Therefore, ink droplets are not ejected. Further, since the switching element SW1 is off, the drive pulse voltage is not applied to the piezoelectric elements 110 of the nozzle elements # 1 and # 2, and remains stopped.

  Next, in the period T (2) -A in FIG. 4, since the switching elements SW1 and SW2 are both off, the nozzle elements # 1 and # 2 remain stopped, and the nozzle elements # 3 and # 4 are also stopped. It will be stopped.

  In the period of T (2) -B, both the switching elements SW1 and SW2 are on. Therefore, the B-phase driving pulse voltage is applied to the nozzle elements # 1 to 4, and at the time t3, the piezoelectric element 110 and the ink pressurizing chamber 140 are expanded and contracted as shown in FIG. Accordingly, control is performed so that ink droplets are ejected from the nozzle elements # 2 and # 4.

  Although the operation of the four nozzle elements # 1 to # 4 has been described above, the same control is possible even if the number of nozzle elements increases. That is, in order to eject ink droplets from a desired nozzle element among a large number of nozzle elements, a switching element connected to the nozzle element may be driven with an A phase drive pulse when the nozzle element is an odd number. . Further, when the nozzle element is an even-numbered nozzle, it may be driven with a B phase drive pulse. Ink droplets cannot be ejected simultaneously from adjacent odd nozzle elements and even nozzle elements, but the recording data recorded by the odd nozzle elements and the recording data recorded by the even nozzle elements are converted into the A phase driving pulse and the B phase driving pulse. It is possible to cope by shifting based on the time difference.

  As described above, in the ink jet recording apparatus according to the present invention, a large number of nozzle elements constituting a recording head are grouped for every two adjacent nozzle elements, and the two adjacent nozzle elements are polarized. Since the piezoelectric elements having the opposite polarities and the polarization magnitudes are substantially the same, and each piezoelectric element is driven by the drive pulse voltage having the same waveform, the diaphragm in these two nozzle elements The vibration of the piezoelectric element, the state of vibration applied to the piezoelectric element support substrate, the displacement of each part, etc. are completely reversed. For this reason, when the piezoelectric vibrators of these two adjacent nozzle elements are driven, the excitation force to other parts, that is, the excitation to a common member such as another nozzle element, piezoelectric element support substrate, housing, etc. Since the force is suppressed, abnormal vibration due to driving of the piezoelectric vibrator is suppressed. Therefore, according to the present invention, abnormal vibration of the meniscus is eliminated, crosstalk is reduced, and stable ink droplet ejection is possible.

  In addition, according to the present invention, since two adjacent nozzle elements are connected to one switching element, the number of switching elements is halved compared to the prior art, and the recording head and the recording head driving device are connected. The number of cables to be used is also halved. Therefore, it is advantageous for reducing the cost and size of the recording apparatus.

  The above embodiment is an example in which the direction of the polarization 1123 of the piezoelectric element 110 is opposite to that of the adjacent nozzle, but the direction of the polarization 1123 of the piezoelectric element 110 is changed as shown in FIG. Each nozzle may be the same, and the common electrode 1121 may have the same structure as the individual electrode 1122 and may be configured independently for each nozzle. In this case, the common electrode 1121 of the first piezoelectric element and the individual electrode 1122 of the second piezoelectric element are connected by the connection A, and the individual electrode 1122 of the first piezoelectric element and the common electrode of the second piezoelectric element are connected. 1121 is connected by connection B. The connection A is bundled between the pair nozzles and connected to the A & B phase piezoelectric element drive pulse waveform generation circuit 305, and the connection B is connected to the switching element 3041 for each pair nozzle.

  With this configuration, since the drive voltages opposite to each other are applied to the first piezoelectric element and the second piezoelectric element with respect to the polarization polarity, the vibration to the diaphragm is operated in the opposite direction. Is possible.

  According to this embodiment, it is necessary to make the common electrode independent for each nozzle, but the polarization directions of the first piezoelectric element and the second piezoelectric element are changed as in the embodiments of FIGS. There is no need to reverse, and the present invention can be implemented.

(4) Another Embodiment of Recording Head FIG. 5 is a schematic configuration diagram showing a second embodiment of the recording head according to the present invention. In this embodiment, in order to allow two adjacent nozzle elements to share a switching element, the individual electrodes 1122 of the two nozzle elements are connected by wiring on the surface of the piezoelectric element support substrate 113. Yes. Compared to the first embodiment shown in FIG. 2, the area of the individual electrode 1122 ′ formed on the surface of the piezoelectric element support substrate 113 is increased, so that the connection between the cable terminal 161 of the flexible cable 160 and the individual electrode 1122 ′ is achieved. Becomes easier.

  Note that, since two adjacent nozzle elements share a switching element, two wires may be connected on the piezoelectric element drive switching circuit board. In this case, the number of wirings of the flexible cable 160 is the same as the conventional one, but the number of switching elements can be halved.

  FIG. 6 is a schematic configuration diagram showing a third embodiment of the recording head according to the present invention. In this embodiment, the size of the ink inlet 145 is configured to gradually decrease in the direction from the common ink chamber 150 toward the ink pressurizing chamber 140. That is, as compared with the embodiment shown in FIG. 2, the flow path is narrowed in the direction from the common ink chamber 150 to the ink pressurizing chamber 140 to provide fluid diode characteristics.

  With this configuration, when two adjacent nozzle elements are driven with the same drive pulse, the volume of the ink pressurization chamber of the nozzle element on the side that does not eject ink droplets increases, and ink flows from the common ink chamber. At this time, the movement of the meniscus toward the ink pressurizing chamber can be suppressed. For this reason, it is possible to prevent air from being sucked from the nozzle holes and to prevent a decrease in frequency response characteristics of ink discharge.

  In this embodiment, a concave ink reservoir 132 is formed around the nozzle hole 131 on the surface of the orifice plate 130. As a result, the ink stored in the nozzle hole peripheral ink reservoir 132 can be moved to the ink pressurizing chamber side 140, so that the adverse effect caused by the movement of the meniscus to the ink pressurizing chamber 140 side can be more effectively prevented. Can do.

  The recording head according to the present invention described above is suitable for a serial scanning ink jet recording apparatus and a line scanning ink jet recording apparatus. When the recording head of the present invention is used in a serial scanning type ink jet recording apparatus, the orifice plate 130 is set so that the surface of the orifice plate 130 faces the recording paper, and the recording head is arranged in the lateral direction crossing the continuous direction of the longitudinal recording paper. The droplets are moved according to the recording signal (main scanning) to record one line, and then the recording paper is fed by a predetermined amount in the continuous direction of the longitudinal recording paper (sub scanning), and then the next The row image is recorded by main scanning. The main scanning and the sub scanning are repeated to record an image.

  When the recording head of the present invention is used in a line scanning ink jet recording apparatus, a large number of recording heads are arranged in the width direction of the continuous recording paper so as to face the recording paper surface to the full width, and ink droplets are recorded on the recording signal. Depending on the spray. At the same time, the recording sheet is moved in the longitudinal direction of the continuous recording sheet at a high speed to perform main scanning. With this main scanning and ink droplet ejection control, recording dot formation on the scanning line is controlled to obtain a recorded image on the recording paper. According to such an ink jet recording apparatus according to the present invention, a high-quality image can be printed at high speed.

  The present invention can be applied to an industrial liquid dispensing apparatus such as a marking apparatus for a product and a coating film apparatus in addition to the use of an ink jet recording apparatus that records ink on recording paper.

1 is a schematic configuration diagram of an ink jet recording apparatus according to the present invention. 1 is a schematic perspective view showing a first embodiment of a recording head according to the present invention. FIG. 6 is an operation explanatory diagram of the recording head of the present invention. FIG. 6 is an operation explanatory diagram of the recording head of the present invention. FIG. 6 is an operation explanatory diagram of the recording head of the present invention. It is explanatory drawing which shows another Example of this invention recording head. FIG. 6 is a signal waveform diagram of each part for explaining the operation of the recording head of the present invention. 6 is a schematic perspective view showing a second embodiment of the recording head according to the present invention. 6 is a schematic perspective view showing a third embodiment of the recording head according to the present invention.

Explanation of symbols

10: recording head 20: recording head driving device 30: ink droplet 40: recording medium 101: ink flow path unit 102: head housing 103: piezoelectric element unit 110: piezoelectric element 111: layered piezoelectric element 112: layered electrode 1121: common electrode 1122: Individual electrode 1123: Polarization 113: Piezoelectric element support substrate 114: Piezoelectric element support substrate fixing part 120: Diaphragm 122: Diaphragm forming plate 130: Orifice plate 131: Nozzle hole 140: Ink pressurizing chamber 142: Ink flow channel forming plate 145: ink inlet 150: common ink chamber 160: flexible cable 161: flexible cable terminal 301: timing signal generating circuit 302: recording data signal generating circuit 303: piezoelectric element driving data signal generating circuit 304: piezoelectric element driving switching circuit 3041 SW1, SW2: switching elements 3042: switching device drive circuit 305: A & B-phase piezoelectric element drive pulse waveform generator

Claims (10)

A plurality of nozzle elements arranged to eject ink liquid from the nozzle holes by attaching a piezoelectric element to a diaphragm forming a part of the ink pressurizing chamber and deforming the diaphragm according to the expansion and contraction of the piezoelectric element. In the inkjet recording head formed,
The first and second nozzle elements adjacent the diaphragm and the vibration of the front Symbol first nozzle element, vibration of the diaphragm of the second nozzle element is such that the opposite direction, the first and second A drive signal is applied to the piezoelectric element of the nozzle element,
The drive signal source for generating the drive signal is a signal source for generating an A phase drive pulse for generating a positive pulse next to a negative pulse and a B phase drive pulse for generating a negative pulse next to the positive pulse. When the A phase driving pulse is applied to the piezoelectric elements of the first and second nozzle elements, the ink liquid is ejected from the first nozzle element, and when the B phase driving pulse is applied, the second nozzle An ink jet recording head, wherein an ink liquid is ejected from an element . 2. The ink jet recording head according to claim 1, wherein the first and second nozzle elements adjacent to each other have a piezoelectric element having polarization polarities opposite to each other . In Claim 2 , each piezoelectric element of the adjacent first and second nozzle elements has a common electrode and an individual electrode, and the common electrode is connected to a drive signal source for driving the piezoelectric element, Each individual electrode is connected to a common switching element, and the drive signal of the drive signal source is applied to the piezoelectric elements of the first and second nozzle elements in accordance with opening and closing of the switching element. An inkjet recording head.   4. The individual electrodes of the piezoelectric elements of the first and second nozzle elements according to claim 3, wherein the individual electrodes are electrically connected by wiring on a piezoelectric element support substrate and then connected to the switching element. An inkjet recording head. 2. The piezoelectric element of each of the adjacent first and second nozzle elements has a common electrode and an individual electrode, and the common electrode of the first nozzle element and the individual electrode of the second nozzle element are defined in claim 1. Is connected to a drive signal source for driving the piezoelectric element, the common electrode of the second nozzle element and the individual electrode of the first nozzle element are connected to the switching element, and according to opening and closing of the switching element An ink jet recording head, wherein a drive signal of the drive signal source is applied to the piezoelectric elements of the first and second nozzle elements.   2. The ink pressurizing chamber of the nozzle element according to claim 1, further comprising an ink inlet port for allowing ink to flow into the ink pressurizing chamber from a common ink chamber, and the ink inlet port is provided in the common ink chamber. An ink jet recording head characterized in that the cross-sectional area on the ink pressurizing chamber side is smaller than the cross-sectional area on the side. 2. The ink jet recording according to claim 1, wherein the nozzle hole is formed in an orifice plate , and an ink reservoir is formed by forming a step by making the periphery of the opening of the nozzle hole lower than the surface of the orifice plate. head. An ink jet recording apparatus comprising the ink jet recording head according to any one of claims 1 to 7.   An orifice plate having a plurality of nozzle holes arranged in a row, an ink flow path forming plate having an ink pressurizing chamber corresponding to the nozzle hole, and one surface of the ink pressurizing chamber are formed. Inkjet recording having a recording head comprising: an ink flow path unit formed integrally with a diaphragm plate provided on the substrate; and a piezoelectric element unit having a plurality of piezoelectric elements having tips bonded to the diaphragm plate In the apparatus, an ink pressurizing chamber having the nozzle hole as an open end, and a piezoelectric element that expands and contracts according to a recording signal and deforms a diaphragm formed on one surface of the ink pressurizing chamber to discharge ink liquid. And a second nozzle element having a piezoelectric element adjacent to the first nozzle element and having a polarity opposite to that of the piezoelectric element of the first nozzle element. And a common switching element connected to the individual electrode of the piezoelectric element of the second nozzle element, and a drive signal source connected to the common electrode of the piezoelectric element of the first and second nozzle elements. An ink jet recording apparatus. 10. The drive signal source according to claim 9 , wherein the drive signal source generates an A-phase drive pulse that generates a positive pulse after at least a negative pulse, and a B-phase drive pulse that generates a negative pulse after the positive pulse , An inkjet recording apparatus, wherein one of the A-phase and B-phase driving pulses is selected by a switching element and applied to both of the piezoelectric elements of the first and second nozzle elements.

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