JP2015006777A - Liquid jet device and control method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet device for use in jetting a liquid while relatively moving a liquid jet head and a jetted target, with a novel configuration enabling suppression of a shift in the drop position of the liquid, and a control method for the device.SOLUTION: A liquid jet device includes: control means 41 capable of controlling a size of a liquid jetted from a nozzle by selectively applying a jetting pulse to pressure-generation means; and storage means 46 for storing a control table representing control information related to jetting control of the liquid. Further, the control table includes control information corresponding to a combination of a size of a liquid jetted from a nozzle, the number of nozzles to jet simultaneously among the nozzle set, a frequency of a drive signal, and a distance between a liquid jet head 3 and a jetting target; and the control means controls liquid-jetting of the liquid jet head on the basis of the control information included in the control table.

Description

  The present invention relates to a liquid ejecting apparatus such as an ink jet recording apparatus, and a control method therefor, and more particularly to a liquid ejecting apparatus that ejects liquid while relatively moving a liquid ejecting head and a landing target, and a control method therefor. It is.

  The liquid ejecting apparatus is an apparatus that includes a liquid ejecting head capable of ejecting liquid as droplets from a nozzle and ejects various liquids from the liquid ejecting head. A typical example of the liquid ejecting apparatus is an ink jet recording that includes an ink jet recording head (hereinafter referred to as a recording head) and performs recording by ejecting liquid ink as ink droplets from the nozzle of the recording head. An image recording apparatus such as an apparatus (hereinafter referred to as a printer) can be given. In addition, liquid ejecting devices are used for ejecting various types of liquids such as color materials used for color filters such as liquid crystal displays, organic materials used for organic EL (Electro Luminescence) displays, and electrode materials used for electrode formation. It is used. The recording head for the image recording apparatus ejects liquid ink, and the color material ejecting head for the display manufacturing apparatus ejects solutions of R (Red), G (Green), and B (Blue) color materials. The electrode material ejecting head for the electrode forming apparatus ejects a liquid electrode material, and the bioorganic matter ejecting head for the chip manufacturing apparatus ejects a bioorganic solution.

  Some printers perform recording by moving the recording head in the width direction of a recording medium such as recording paper (a kind of landing target), that is, in the main scanning direction. The recording head ejects liquid ink from the nozzles by applying an ejection pulse (a kind of ejection drive voltage) to a piezoelectric element (a kind of pressure generating means) and driving the piezoelectric element. The printer has a plurality of types of ejection pulses with different amounts of ejected ink droplets, and by selectively supplying the necessary ejection pulses from the ejection pulses to the piezoelectric element, different sizes are obtained. Dots are formed on a recording medium (a kind of landing target).

  In the printer having such a configuration, since the ink is ejected while moving the recording head, the ejected ink droplets fly obliquely with respect to the recording medium due to the inertial force resulting from the movement of the recording head. For this reason, when ink droplets having different flying speeds are ejected, the time required for the ink droplets to land on the recording medium differs for each ink droplet. For example, a small amount of ink droplets corresponding to small dots and a large amount of ink droplets corresponding to large dots have different flight speeds due to differences in air resistance, etc. Different. As a result, the landing position may vary depending on the amount (size) of ejected ink droplets. That is, there is a possibility that the landing position of the ink droplets is shifted. In order to adjust the deviation of the landing position, there has been proposed a printing apparatus that performs printing while correcting the deviation amount of the bullet position based on an adjustment value corresponding to the dot size (ink droplet amount) (for example, a patent). Reference 1).

JP 2009-234071 A

  However, only the correction according to the amount (size) of ink droplets as described above cannot sufficiently suppress the deviation of the landing position. Various factors can be considered as the cause. For example, when ink is ejected from a nozzle array formed by arranging a plurality of nozzles, the flying speed of ink droplets changes depending on the number of nozzles that eject ink simultaneously. Further, the flying speed of the ink droplet changes depending on the difference in the frequency of the drive signal, that is, the interval between the ejection pulse applied first and the ejection pulse applied next when ejecting ink from the nozzles continuously. Further, the time from the ejection of the ink droplet to the landing on the recording medium varies depending on the distance between the recording head and the recording medium. In addition, the landing position of the ink droplet may be shifted due to such a change in the flying speed.

  The present invention has been made in view of such circumstances, and an object of the present invention is to suppress displacement of a liquid landing position in a liquid ejecting apparatus that ejects liquid while relatively moving a liquid ejecting head and a landing target. An object of the present invention is to provide a liquid ejecting apparatus and a method for controlling the liquid ejecting apparatus.

The liquid ejecting apparatus of the present invention has been proposed in order to achieve the above-described object. The liquid ejecting apparatus has a nozzle group in which a plurality of nozzles are arranged, and drives the pressure generating means by applying an ejection pulse. A liquid ejecting head that ejects liquid from a nozzle to land on a landing target;
A drive signal generator capable of repeatedly generating a drive signal including a plurality of ejection pulses;
Moving means for relatively moving the liquid ejecting head and the landing target;
Control means capable of controlling the size of the liquid ejected from the nozzle by selectively applying the ejection pulse to the pressure generating means;
Storage means for storing a control table in which control information relating to liquid ejection control is indicated;
With
The control table includes the size of the liquid ejected from the nozzle, the number of nozzles that simultaneously eject liquid in the nozzle group, the frequency of the drive signal, and the distance between the liquid ejecting head and the landing target. It has control information corresponding to the combination,
The control means controls liquid ejection by the liquid ejection head based on control information in the control table.

In the above configuration, the control information is a correction value for correcting a shift in the landing position of the liquid,
The control means preferably corrects the waveform of the injection pulse or the timing of applying the injection pulse to the pressure generating means based on the correction value.

The control method of the liquid ejecting apparatus of the present invention includes a nozzle group in which a plurality of nozzles are arranged in a row, and the liquid is ejected from the nozzles by driving the pressure generating means by applying the ejecting pulses to be landed. A liquid ejecting head to land on,
A drive signal generator capable of repeatedly generating a drive signal including a plurality of ejection pulses;
Moving means for relatively moving the liquid ejecting head and the landing target;
Control means capable of controlling the size of the liquid ejected from the nozzle by selectively applying the ejection pulse to the pressure generating means;
Storage means for storing a control table in which control information relating to liquid ejection control is indicated;
A control method for a liquid ejecting apparatus comprising:
The size corresponding to the combination of the size of the liquid ejected from the nozzles, the number of nozzles that simultaneously eject liquid in the nozzle group, the frequency of the drive signal, and the distance between the liquid ejecting head and the landing target The liquid ejecting by the liquid ejecting head is controlled based on the control information in the control table.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the liquid injected from the nozzle slip | deviates from the original target position on a landing target. Thereby, deterioration of image quality, such as an image formed on the landing target, can be suppressed. In addition, since the liquid ejection by the liquid ejection head is controlled based on the control table, it is not necessary to calculate control information for each liquid ejection. For this reason, the load of the control means can be reduced.

FIG. 3 is a perspective view illustrating a configuration of a printer. It is a schematic sectional drawing of a recording head. 2 is a block diagram illustrating an electrical configuration of a printer. FIG. It is a wave form diagram explaining an example of an injection pulse. It is a figure explaining an example of a control table.

  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 printer (hereinafter referred to as a printer) equipped with an ink jet recording head (hereinafter referred to as a recording head) is taken as an example of the liquid ejecting apparatus of the present invention.

  The configuration of the printer 1 will be described with reference to FIG. The printer 1 is a device that records an image or the like by ejecting liquid ink onto the surface of a recording medium 2 (a kind of landing target) such as recording paper. The printer 1 includes a recording head 3 that ejects ink, a carriage 4 to which the recording head 3 is attached, a carriage moving mechanism 5 (corresponding to a moving unit in the present invention) that moves the carriage 4 in the main scanning direction, and a recording medium 2. A transport mechanism 6 or the like that transports in the sub-scanning direction is provided. The ink is stored in an ink cartridge 7 as a liquid supply source. The ink cartridge 7 is detachably attached to the recording head 3. It is also possible to employ a configuration in which the ink cartridge 7 is disposed on the main body side of the printer 1 and is supplied from the ink cartridge 7 to the recording head 3 through an ink supply tube.

  The carriage moving mechanism 5 includes a timing belt 8. The timing belt 8 is driven by a pulse motor 9 such as a DC motor. Accordingly, when the pulse motor 9 is operated, the carriage 4 is guided by the guide rod 10 installed on the printer 1 and reciprocates in the main scanning direction (width direction of the recording medium 2). The position of the carriage 4 in the main scanning direction is detected by a linear encoder 11 which is a kind of position information detecting means. The linear encoder 11 transmits the detection signal, that is, an encoder pulse (a kind of position information) to the control unit 41 (see FIG. 3) of the printer 1.

  Next, the recording head 3 will be described. FIG. 2 is a schematic sectional view of the recording head 3. In FIG. 2, the configuration of the main part corresponding to the other nozzle row is omitted because it is symmetrical in the left-right direction with respect to the illustrated one. As shown in FIG. 2, the recording head 3 in the present embodiment includes a pressure generating unit 17 and a flow path unit 18, and these members are stacked and attached to a case 23.

  The case 23 is a box-shaped member formed of synthetic resin or the like. As shown in FIG. 2, a through-hole portion 34 that is long along the nozzle row direction is formed in the center portion of the case 23 so as to penetrate the height direction of the case 23. Then, one end of a flexible cable (not shown) is accommodated in the through space 34. In addition, an ink introduction path 35 is formed in the case 23. The ink introduction path 35 has an upper end connected to the upstream flow path and a lower end connected to the common liquid chamber 29 (reservoir) of the flow path unit 18. As a result, the ink from the ink cartridge 7 is introduced into the common liquid chamber 29 via the ink introduction path 35.

  The flow path unit 18 includes a nozzle plate 19 (a kind of nozzle forming member) in which a plurality of nozzles 24 are opened in a straight line (row shape), and a communication substrate 20 provided with a common liquid chamber 29. The plurality of nozzles 24 arranged in a row are provided at equal intervals from the nozzle 24 on one end side to the nozzle 24 on the other end side at a pitch corresponding to the dot formation density. In the present embodiment, a nozzle row (a kind of nozzle group) is configured by arranging 360 nozzles 24 at a pitch corresponding to 360 dpi. In the present embodiment, two nozzle rows are formed on the nozzle plate 19. The common liquid chambers 29 are empty portions formed in series along the nozzle row direction, and two rows are formed corresponding to the two nozzle rows. On the nozzle 24 side (pressure chamber 28 side) of the common liquid chamber 29, a plurality of liquid inlets 30 communicating with the pressure chamber 28 are provided corresponding to the pressure chambers 28.

  The pressure generating unit 17 is unitized by laminating a pressure chamber forming substrate 26 (a kind of pressure chamber forming member) on which a pressure chamber 28 is formed, an elastic film 27, a piezoelectric element 31, and a protective substrate 21. Then, ink is introduced from the common liquid chamber 29 into the pressure chamber 28 via the liquid inlet 30, and the drive signal from the control unit 41 is supplied to the piezoelectric element 31 via the flexible cable. Driven to cause pressure fluctuation in the pressure chamber 28. By utilizing this pressure fluctuation, ink droplets are ejected from the nozzles 24 through the nozzle communication passages 32 penetrating the communication substrate 20.

  Then, the ink introduced from the ink cartridge 7 into the common liquid chamber 29 through the ink introduction path 35 is introduced into the pressure chamber 28 through the liquid introduction port 30. When a drive signal from the control unit 41 is supplied to the piezoelectric element 31 in a state where the pressure chamber 28 is filled with ink, the piezoelectric element 31 bends and a pressure fluctuation occurs in the pressure chamber 28. The recording head 3 uses this pressure fluctuation to eject ink droplets from the nozzles 24.

  Next, the electrical configuration of the printer 1 will be described. FIG. 3 is a block diagram illustrating the electrical configuration of the printer 1. The printer 1 in this embodiment includes a carriage moving mechanism 5, a transport mechanism 6, a linear encoder 11, a recording head 3, 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 transmits print data corresponding to the image or the like to the printer 1 so that the printer 1 prints an image or text on the recording medium 2. .

  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 (corresponding to a storage unit in the present invention), and a drive signal generation. Part 47 (corresponding to the drive signal generating part in the present invention). 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 unit for controlling the entire printer 1, and controls each unit according to a program stored in the storage unit 46. In addition, the CPU 45 functions as a timing pulse generation unit that generates a timing pulse PTS from the encoder pulse output from the linear encoder 11. Then, the CPU 45 controls transmission of print data, generation of the drive signal COM by the drive signal generation unit 47, and the like in synchronization with the timing pulse PTS.

  Further, the CPU 45 generates ejection data used for ejection control of the recording head 3 based on the print data. This ejection data is data relating to pixels of an image to be printed. Here, the pixel indicates a dot formation region virtually defined on the recording medium 2. The ejection data according to the present invention includes gradation data relating to the presence / absence of dots formed on the recording medium 2 (or presence / absence of ink ejection) and the size of the dots (or the amount of ink ejected). In the present embodiment, the ejection data is composed of binary gradation data having a total of 2 bits. For 2-bit gradation values, [00] corresponding to non-printing without ink ejection, [01] corresponding to small dot recording, [10] corresponding to medium dot recording, and large dot There is [11] corresponding to recording. Therefore, the printer 1 in the present embodiment can perform recording with four gradations.

  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 storage unit 46 stores in advance a control table in which control information related to ink ejection control is shown. In the present embodiment, a correction value (timing correction value) for correcting the deviation of the ink landing position is stored as the control information. As shown in FIG. 5, each correction value includes the size of ink ejected from the nozzles 24 (dot size), the number of nozzles 24 that eject ink simultaneously in the nozzle row (the number of simultaneous ejection nozzles), and the frequency of the drive signal ( A value corresponding to a combination of the driving frequency) and the thickness of the recording medium 2 (thickness of the recording medium) is determined and stored in advance. The CPU 45 reads correction values corresponding to these four parameters from the storage unit 46, and corrects (controls) the timing of ink ejected from the nozzles 24, that is, the timing of applying ejection pulses to the piezoelectric element 31 based on the correction values. ) The correction of the ink ejection timing will be described in detail later.

  The drive signal generation unit 47 generates an analog voltage signal based on the waveform data regarding the waveform of the drive signal COM. The drive signal generation unit 47 amplifies the voltage signal to generate a drive signal COM. Here, the drive signal COM is a series of signals including a plurality of ejection pulses within a unit period T that is a generation repetition period of the drive signal COM. The ejection pulse is a type of drive voltage that causes the piezoelectric element 31 to perform a predetermined operation in order to perform a recording operation of ejecting ink from the nozzles 24 of the recording head 3. For example, the drive signal COM includes a series of ejection pulses corresponding to large dots, ejection pulses corresponding to medium dots, and ejection pulses corresponding to small dots. The unit period T, which is the repetition period of the drive signal COM, is a distance corresponding to the width of the pixel when the nozzle 24 ejects ink while the recording head 3 moves relative to the recording medium 2. This corresponds to the moving time, and is set to several tens of μs, for example. That is, in this case, the repetition frequency of the drive signal is several tens of kHz.

  FIG. 4 is a waveform diagram for explaining an example of the injection pulse. In FIG. 4, the vertical axis represents voltage and the horizontal axis represents time. The injection pulse includes an expansion element p1, an expansion maintenance element p2, a contraction element p3, a contraction maintenance element p4, and a return element p5. The expansion element p1 expands the pressure chamber 28 by changing the potential from the reference potential (intermediate potential) VB to the minimum potential (minimum voltage) VL in the negative direction. The expansion maintaining element p2 maintains the minimum potential VL for a certain time. The contraction element p3 rapidly contracts the pressure chamber 28 by changing the potential from the minimum potential VL to the maximum potential (maximum voltage) VH in the positive direction. The contraction maintaining element p4 maintains the maximum potential VH for a certain time. The return element p5 returns the potential from the maximum potential VH to the reference potential VB. In such an ejection pulse, the amount of ink ejected from the nozzle 24 varies depending on the potential difference Vd between the minimum potential VL and the maximum potential VH (voltage variation amount of the contraction element p3). For example, when it is desired to increase the amount of ink ejected from the nozzle 24 (in the case of a large dot), an ejection pulse having a large potential difference Vd between the minimum potential VL and the maximum potential VH is used. On the other hand, when it is desired to reduce the amount of ink ejected from the nozzle 24 (in the case of small dots), an ejection pulse having a small potential difference Vd between the minimum potential VL and the maximum potential VH is used. In addition, the ejection pulse is not limited to the illustrated waveform, but can be an ejection pulse that ejects ink corresponding to each dot size using waveforms having various configurations.

  The head controller 43 performs application control of the drive signal COM to the piezoelectric element 31 of the recording head 3 based on the head control signal from the CPU 45. Further, the head controller 43 generates pulse selection data based on the ejection data from the CPU 45. Based on this pulse selection data, the ejection pulse corresponding to the dot size is selected from the drive signal COM. When the ejection pulse is applied to the piezoelectric element 31, a predetermined amount (design target amount) of ink is designed to be ejected from the nozzle 24 at a constant speed. As a result, the ink lands on the dot formation area on the recording medium 2 to form a dot having a size corresponding to the selected ejection pulse. The control unit 41 and the head control unit 43 correspond to the control means in the present invention.

  By the way, in a conventional printer that does not correct the ejection pulse application timing, the ink ejected from the nozzles 24 may deviate from the original target position on the recording medium 2. Since the recording head 3 (carriage 4) ejects ink droplets while moving relative to the recording medium 2, the ejected ink droplets fly obliquely with respect to the recording medium 2 by inertial force. For this reason, if the ink droplet ejected from the nozzle 24 deviates from the original target flying speed, the time until the ink droplet lands on the recording medium 2 deviates, and the landing position of the ink droplet deviates from the original target position. Here, the flying speed of the ink droplets (the average speed of the ink droplets from when ejected from the nozzle 24 until landing on the landing target) is the size of the ink ejected from the nozzle 24, and the nozzle that ejects ink simultaneously in the nozzle row There is a possibility of changing depending on the number of 24, the frequency of the drive signal, and the thickness of the recording medium 2.

  The change in the flying speed of the ink droplet will be described in more detail. When the size of ink droplets ejected from the nozzle 24 (the amount of ink droplets) is different, the gravity acting on the ink droplets, the air resistance received by the ink droplets during flight, and the like are different. For this reason, the flying speed of the ink droplet changes depending on the size of the ink droplet, and the landing position is shifted. In addition, since the so-called crosstalk occurs depending on the number of nozzles 24 that simultaneously eject ink in the nozzle array (the ratio of the nozzles 24 that simultaneously eject ink to all the nozzles 24 constituting the nozzle array), the flying speed of the ink droplets is increased. change. This crosstalk is caused by the fact that the partition walls defining the pressure chambers 28 bend due to an increase in the internal pressure of the pressure chambers 28 when ink is ejected. For example, when ink is ejected from only one nozzle 24 of the nozzles 24 constituting the nozzle row, the partition wall is distorted to the outside, resulting in pressure loss and slow flight speed. On the other hand, when ink is ejected from the plurality of nozzles 24 constituting the nozzle row, the pressure from the other nozzles 24 to be ejected is transmitted through the adjacent pressure chambers 28, and the distortion of the partition walls is suppressed. As a result, pressure loss is suppressed. For this reason, as the number of nozzles 24 that simultaneously eject ink in the nozzle row increases, the flying speed of ink droplets tends to increase, and as the number decreases, the flying speed of ink droplets tends to decrease. Due to the difference in the flying speed, the landing position of the ink droplet may be shifted.

  Furthermore, the flying speed of ink droplets may change depending on the frequency of the drive signal (cycle of the drive signal). This is because, when ink is continuously ejected from the nozzle 24, the residual vibration of the ink ejected first affects the ink ejected next. That is, residual vibration remains in the pressure chamber 28 after ejecting an ink droplet, and the behavior of the meniscus is disturbed, affecting the ejection of the next ink droplet. In particular, when ink droplets are ejected continuously in a very short time, the influence of this residual vibration becomes significant, and the flight speed tends to change. In this case, the amount of ink supplied to the pressure chamber 28 is also reduced, and the amount of ink droplets and the flying speed may change. As a result, the landing positions of the ink droplets may be shifted. The flying speed of the ink droplet also changes depending on the thickness of the recording medium 2. When the thickness of the recording medium 2 changes, the distance between the recording head 3 and the recording medium 2 (the interval between the nozzle plate 19 and the recording medium 2) changes, and the time from ink droplet ejection to landing on the recording medium 2 Changes. That is, the average flying speed of ink droplets changes. For this reason, the landing positions of the ink droplets are shifted.

  In order to suppress the landing position deviation due to such a change in flying speed, in the present invention, the size of the ink ejected from the nozzles 24, the number of nozzles 24 ejecting ink simultaneously in the nozzle row, the frequency of the drive signal, Further, a correction value corresponding to a combination of the thicknesses of the recording medium 2 (distance between the recording head 3 and the recording medium 2) is stored in the storage unit 46 as a control table, and the piezoelectric of the ejection pulse is based on this correction value. The application timing to the element 31 is corrected (controlled). In the present embodiment, as shown in FIG. 5, the correction value is changed corresponding to the case where the size (dot size) of the ink ejected from the nozzle 24 is “large”, “medium”, and “small”. ing. In addition, the correction value is changed in two ways of “large” and “small” in the number of nozzles 24 that simultaneously eject ink in the nozzle row (the number of simultaneous ejection nozzles). For example, the number of nozzles to be used (injected) is calculated in advance from the print data, and the correction value is changed between the case where the number is larger than this and the case where it is less than this, based on half the number of nozzles 24 constituting the nozzle row. .

  Further, the correction value is changed in two ways of “high” and “low” of the frequency of the drive signal (drive frequency). For example, the correction value is changed when the setting of the printer 1 is set to a low image quality mode with a high driving frequency and when the printer 1 is set to a high image quality mode with a low driving frequency. In addition, the correction value is changed in two ways: “thick” and “thin”. For example, the correction value is changed between when the printer 1 is set to a mode for printing on a thick recording medium 2 such as a postcard and when it is set to a mode for printing on a thin recording medium 2 such as copy paper. ing. The printer 1 may be provided with a measuring unit that measures the distance from the recording head 3 (nozzle plate 19) to the recording medium 2, and the correction value may be changed according to the measurement result.

  As described above, in the control table of the present embodiment, there are three “dot sizes”, two “number of simultaneous ejection nozzles”, two “drive frequencies”, and two “recording medium thicknesses”. The correction values corresponding to these combinations are set in 24 ways (ΔT1 to ΔT24). These values are stored in the storage unit 46 as a control table. Each correction value can be obtained in advance by experiments, simulations, or the like so that the ink droplets ejected from the nozzles 24 land on the original target position on the recording medium 2. Then, the CPU 45 reads the corresponding correction value from the combination of “dot size”, “number of simultaneous ejection nozzles”, “drive frequency”, and “printing medium thickness” from the storage unit 46, and controls the head control unit 43. Then, the application timing of the ejection pulse to the piezoelectric element 31 is controlled (corrected). For example, when the correction value is a positive value, the timing of applying the injection pulse to the piezoelectric element 31 is corrected so that the timing of the injection pulse is delayed from a predetermined reference timing according to the value of the correction value. . When the correction value is a negative value, the timing of applying the injection pulse to the piezoelectric element 31 is corrected so that the timing of the injection pulse is earlier than a predetermined reference timing according to the value of the correction value. When the timing correction value is zero, the injection pulse is applied to the piezoelectric element 31 according to a predetermined reference timing without correcting the timing of the injection pulse.

  Thereby, it is possible to suppress the ink ejected from the nozzles 24 from deviating from the original target position on the recording medium 2. As a result, it is possible to suppress deterioration in image quality such as an image formed on the recording medium 2. Further, since the ejection of ink by the recording head 3 is controlled based on the control table, it is not necessary to calculate a correction value for each ejection of ink. For this reason, the load of the control unit 41 (CPU 45) can be reduced. As a result, it is possible to contribute to speeding up of the liquid ejecting process such as the printing process.

  By the way, in the said embodiment, although the correction value which correct | amends the timing of an injection pulse was illustrated, it is not restricted to this. For example, it may be a correction value for correcting the waveform of the injection pulse. Specifically, the flying speed of the ink droplet can be changed by correcting the inclination of the contraction element p3 of the ejection pulse based on the correction value. For example, when it is desired to increase the flying speed so that the landing position of the ink droplet is closer to the recording head movement direction (main scanning direction), the correction value for correcting the inclination of the contraction element p3 to be steep is controlled. It memorize | stores in a memory | storage part as a table. On the other hand, when the flying speed is slowed down and the landing position of the ink droplet is desired to be the back side in the recording head movement direction (main scanning direction), the correction value for correcting the inclination of the contraction element p3 to be gentle is controlled. It memorize | stores in a memory | storage part as a table. Based on this correction value, the waveform of the drive signal COM is generated.

  In the control table of the above embodiment, four parameters related to the change in flying speed (the size of ink ejected from the nozzles, the number of nozzles ejecting ink simultaneously in the nozzle array, the frequency of the drive signal, and the recording) Although 24 combinations of the distance between the head and the recording medium (thickness of the recording medium) are set, that is, 24 correction values are set, this is not restrictive. For example, the case classification of each parameter may be set more finely, and a control table composed of more combinations may be stored in the storage unit.

  Furthermore, although the so-called flexural vibration type piezoelectric element 31 has been exemplified as the pressure generating means in the above, 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, regarding the ejection pulse exemplified in the above embodiment, the waveform changes in the direction of potential change, that is, upside down. Other pressure generation means include heat generating elements that generate pressure fluctuations by generating bubbles in the ink by heat generation, electrostatic actuators that generate pressure fluctuations by displacing the partition walls of the pressure chamber by electrostatic force, etc. The present invention can also be applied to a configuration that employs the pressure generating means.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 2 ... Recording medium, 3 ... Recording head, 4 ... Carriage, 5 ... Carriage moving mechanism, 6 ... Conveyance mechanism, 7 ... Ink cartridge, 8 ... Timing belt, 11 ... Linear encoder, 17 ... Pressure generating unit, DESCRIPTION OF SYMBOLS 18 ... Channel unit, 19 ... Nozzle plate, 20 ... Communication board, 21 ... Protection board, 23 ... Case, 24 ... Nozzle, 26 ... Pressure chamber formation board, 27 ... Elastic film, 28 ... Pressure chamber, 29 ... Common liquid Chamber, 30 ... Liquid inlet, 31 ... Piezoelectric element, 32 ... Nozzle communication passage, 34 ... Pass-through cavity, 35 ... Ink introduction passage, 41 ... Control section, 43 ... Head control section, 45 ... CPU, 46 ... Storage section , 47... Drive signal generator

Claims (3)

A liquid ejecting head having a nozzle group in which a plurality of nozzles are arranged, and ejecting liquid from the nozzles by driving the pressure generating means by applying an ejection pulse to land on a landing target;
A drive signal generator capable of repeatedly generating a drive signal including a plurality of ejection pulses;
Moving means for relatively moving the liquid ejecting head and the landing target;
Control means capable of controlling the size of the liquid ejected from the nozzle by selectively applying the ejection pulse to the pressure generating means;
Storage means for storing a control table in which control information relating to liquid ejection control is indicated;
With
The control table includes the size of the liquid ejected from the nozzle, the number of nozzles that simultaneously eject liquid in the nozzle group, the frequency of the drive signal, and the distance between the liquid ejecting head and the landing target. It has control information corresponding to the combination,
The liquid ejecting apparatus according to claim 1, wherein the control unit controls liquid ejection by the liquid ejecting head based on control information in the control table. The control information is a correction value for correcting the deviation of the landing position of the liquid,
2. The liquid ejecting apparatus according to claim 1, wherein the control unit corrects a waveform of the ejection pulse or an application timing of the ejection pulse to the pressure generating unit based on the correction value. 3. A liquid ejecting head having a nozzle group in which a plurality of nozzles are arranged, and ejecting liquid from the nozzles by driving the pressure generating means by applying an ejection pulse to land on a landing target;
A drive signal generator capable of repeatedly generating a drive signal including a plurality of ejection pulses;
Moving means for relatively moving the liquid ejecting head and the landing target;
Control means capable of controlling the size of the liquid ejected from the nozzle by selectively applying the ejection pulse to the pressure generating means;
Storage means for storing a control table in which control information relating to liquid ejection control is indicated;
A control method for a liquid ejecting apparatus comprising:
The size corresponding to the combination of the size of the liquid ejected from the nozzles, the number of nozzles that simultaneously eject liquid in the nozzle group, the frequency of the drive signal, and the distance between the liquid ejecting head and the landing target A liquid ejecting apparatus control method, comprising: controlling liquid ejection by the liquid ejecting head based on control information in a control table.

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