JP2016002711A - Ink discharge device, control device, and ink discharge control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink discharge device which can reduce maximum power consumption while reducing effect on productivity and discharge performance.SOLUTION: An ink discharge device includes: head means having a first discharge port group H1, H3, H5, H7, and a second discharge port group H2, H4, H6, H8; discharge timing setting means which sets ink discharge timings respectively to the first discharge port group and the second discharge port group; and discharge speed setting means which sets ink discharge speeds in response to the set ink discharge timings respectively to the first discharge port group and the second discharge port group. The ink discharge timing set to the first discharge port group is delayed than the ink discharge timing set to the second discharge port group, and the ink discharge speed set to the first discharge port group is higher than the ink discharge speed set to the second discharge port group.

Description

  The present invention relates to an ink discharge technique, and more particularly to an ink discharge apparatus, a control apparatus, and an ink discharge control method for discharging ink from a plurality of discharge ports.

  2. Description of the Related Art Conventionally, a so-called line head type ink jet printer is known that uses a relatively long printer head to complete printing in a single pass only by movement of a recording medium. In a line head type printer, there are cases where ejection is performed simultaneously from a large number of ejection ports, so that power consumption during ink ejection increases. Conventionally, in order to cope with an increase in power consumption due to simultaneous ejection, a technique for reducing the number of simultaneously ejected ink ejection ports by controlling ejection timing while maintaining ejection performance is known.

  For example, Japanese Patent No. 4285534 (Patent Document 1) discloses a technique for reducing the maximum power consumption of a line head printer. Japanese Patent Application Laid-Open No. 2004-133867 discloses a liquid ejection apparatus having an upstream nozzle group and a downstream nozzle group located downstream in the transport direction with respect to the upstream nozzle group. The transport speed varies depending on the number of nozzle rows used. The configuration to be disclosed is disclosed.

  Japanese Patent Laying-Open No. 2013-193284 (Patent Document 2) discloses a technique for reducing a peak current when driving a head when a head array in which a plurality of heads are arranged is used. In the prior art of Patent Document 2, each head having two nozzle rows is arranged so that the head rows are staggered every two rows, and at least one of the nozzle rows on one line aligned in the nozzle arrangement direction. A configuration is disclosed in which one nozzle row is assigned to eject droplets of a different color from the other nozzle rows.

  However, the printer according to the conventional technique of Patent Document 1 described above is not sufficient in that the productivity is impaired because the conveyance speed is reduced together with the discharge timing control. In the prior art of Patent Document 2, although the peak power consumption can be reduced to a certain degree by the configuration in which droplets having different colors from other nozzle rows are ejected, it is not sufficient.

  The present invention has been made in view of the insufficiency in the prior art described above, and the present invention can reduce the maximum power consumption of the ink ejection apparatus while reducing the influence on productivity and ejection performance. An object of the present invention is to provide an ink discharge device, a control device, and an ink discharge control method.

  In order to solve the above problems, the present invention provides an ink ejection apparatus having the following characteristics. This ink discharge apparatus sets the ink discharge timing for the head means including the first discharge port group and the second discharge port group, and for the first discharge port group and the second discharge port group, respectively. An ejection timing setting unit; and an ejection rate setting unit configured to set an ink ejection speed corresponding to the set ink ejection timing for each of the first ejection port group and the second ejection port group. At this time, the ink ejection timing set for the first ejection port group is delayed from the ink ejection timing set for the second ejection port group, and the ink ejection speed set for the first ejection port group. Is characterized by being faster than the ink ejection speed set for the second ejection port group.

  With the above configuration, it is possible to reduce the maximum power consumption of the ink ejection apparatus while reducing the influence on productivity and ejection performance.

1 is an overall configuration diagram of an ink jet printer according to an embodiment. FIG. FIG. 3 is a diagram illustrating a configuration of a recording head in the ink jet printer according to the present embodiment. FIG. 3 is a diagram illustrating a configuration of a rotary encoder in the ink jet printer according to the present embodiment. FIG. 3 is a circuit block diagram relating to ink ejection control of the ink jet printer according to the present embodiment. The figure which shows the image which a line head type inkjet printer outputs as an example. FIG. 6 is a diagram for explaining the relationship between (A) ink ejection timing and (B) power of a head when an image as shown in FIG. 5 is output from a conventional inkjet printer. FIG. 6 is a diagram for explaining the relationship between (A) ink ejection timing and (B) power of a recording head when an image as shown in FIG. 5 is output from the ink jet printer according to the present embodiment. 5 is a flowchart illustrating a control method executed by the ink jet printer according to the embodiment.

  Hereinafter, although this embodiment is described, it is not limited to embodiment described below. In the embodiments described below, an example of an ink ejection device and a control device will be described with reference to a line head type inkjet printer 10 and a control device 110 of the inkjet printer 10.

  FIG. 1 is a diagram illustrating an overall configuration of an inkjet printer 10 according to the present embodiment. An ink jet printer 10 shown in FIG. 1 forms an image on a transported recording medium by ejecting ink and a paper feed tray 12 mounted on the apparatus main body for loading paper as a recording medium. And a paper discharge tray 14 for stacking sheets on which images are recorded.

  As a paper feeding unit for feeding the paper stacked on the paper stacking unit of the paper feeding tray 12, there are a paper feeding roller 16 that separates and feeds the paper one by one from the paper stacking unit, and a paper feeding roller 16. A separation pad 18 that is opposed and biased toward the paper feed roller 16 is provided.

  The transport unit for transporting the paper fed from the paper feed unit below the recording head 36 includes a transport belt 20 for transporting the sheet by electrostatic adsorption and a sheet fed substantially vertically upward. A conveyance guide 24 for changing the direction approximately 90 ° to follow the conveyance belt 20 and a tip pressurizing roller 26 urged toward the conveyance belt 20 by a pressing member are provided. In addition, the inkjet printer 10 includes a charging roller 28 for charging the surface of the transport belt 20.

  Here, the conveyance belt 20 is an endless belt, and is configured to be wound around the conveyance roller 30 and the tension roller 32 and to circulate in the belt conveyance direction. A rotary encoder is attached to the transport roller 30, and the rotation amount of the transport roller 30, that is, the transport amount of the recording paper is detected by the rotary encoder. The charging roller 28 is disposed so as to come into contact with the surface layer of the transport belt 20 and rotate following the rotation of the transport belt 20, and applies pressure to both ends of the shaft.

  In addition, a guide member 34 is disposed on the back side of the conveyance belt 20 so as to correspond to a printing area by the recording head 36. The guide member 34 is provided so that the upper surface protrudes toward the recording head 36 from the tangent line of two rollers (the conveyance roller 30 and the tension roller 32) that support the conveyance belt 20. Thereby, the conveyor belt 20 is pushed up and guided by the upper surface of the guide member 34 in the printing region, and high-precision flatness is maintained.

  Further, a plurality of grooves are formed in the main scanning direction, that is, in a direction orthogonal to the conveyance direction, on the surface side of the guide member 34 that contacts the back surface of the conveyance belt 20. Thereby, the contact area with the conveyor belt 20 is reduced, and the conveyor belt 20 can move smoothly along the surface of the guide member 34.

  Further, as a paper discharge unit for discharging the paper recorded by the recording head 36, a separation claw 42 for separating the paper from the conveyor belt 20, a paper discharge roller 44, and a paper discharge roller 46 are provided. The paper discharge tray 14 is provided below the paper discharge roller 44. A double-sided paper feeding unit 48 is detachably mounted on the back surface of the apparatus main body. The double-sided paper feeding unit 48 can take in the paper returned by the reverse rotation of the transport belt 20, reverse it, and feed it to the transport belt 20.

  The recording head 36 is provided with a head tank 50 for temporarily storing ink in order to properly supply ink to the head. The ink is intermittently supplied or constantly supplied from the cartridge loading unit provided in the apparatus main body to the head tank 50 via the ink supply pipe 38 by the supply pump.

  Hereinafter, the recording head 36 according to the present embodiment will be described in detail with reference to FIG. FIG. 2 is a diagram illustrating the configuration of the recording head 36 in the ink jet printer 10 according to the present embodiment. 2A shows a top view of the recording head 36 viewed from above, FIG. 2B shows a front view of the recording head 36 viewed from the front in the transport direction, and FIG. The bottom view which looked at the head array mounting surface of the recording head 36 is shown. As shown in FIG. 2, in the line head type inkjet printer 10, a recording sheet is conveyed under a fixed head array composed of a plurality of heads covering the width of a recording medium, and printing is performed in a single pass. Configured to complete.

  In the recording head 36 shown in FIG. 2, a plurality of identical heads H1 to H8 are arranged in a staggered manner, and the heads (H1, H3, H5, H7; hereinafter referred to as downstream head groups) arranged downstream in the transport direction. And a head (H2, H4, H6, H8; hereinafter referred to as an upstream head group in some cases) installed upstream in the transport direction and displaced in the transport direction. Are arranged. The arrangement of the head array in the recording head 36 shown in FIG. 2 is an example, and is not particularly limited to that shown in FIG. Each head includes a nozzle (discharge port) row for each color (four colors of K (black), C (cyan), Y (yellow), and M (magenta) in the example).

  In the recording head 36, a piezoelectric element that is a driving element (actuator) is further provided corresponding to the nozzle that ejects ink droplets. In the inkjet printer 10, the piezoelectric element is driven by transmitting a voltage signal to the piezoelectric element in the recording head 36. The pressure chamber wall of the channel is deformed in the direction in which the internal pressure increases in accordance with the driving of the piezoelectric element, whereby ink droplets are ejected from the nozzle. An image is formed on the recording medium by ejecting ink droplets from the nozzles of the respective colors arranged in the recording head 36 at necessary positions while conveying the recording medium.

  Hereinafter, the ink ejection control in the ink jet printer 10 according to the present embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram illustrating the configuration of the rotary encoder in the ink jet printer 10 according to the present embodiment.

  As shown in FIG. 3, the transport roller 30 is provided with a rotary encoder 30a in which an optical slit is formed. By detecting the optical slit by the light emitting diode and the photo sensor 22, the rotation amount (conveyance amount of the recording paper) of the conveyance roller 30 is detected. Then, on the basis of the signal output of the photosensor 22 that detects the optical slit of the rotary encoder 30a attached to the transport roller 30, the control device (for example, ASIC) of the inkjet printer 10 has a predetermined resolution to the recording head 36. A discharge signal is sent out.

  In the rotary encoder 30a, a segment (optical slit) composed of a transparent portion and an opaque portion is formed in the code track of the disc corresponding to the recording dot pitch. When the slit width is a predetermined resolution (for example, res = 300 dpi) and an image is output at the same resolution (res = 300 dpi), an ejection signal is output in synchronization with the rising edge of the signal of the photosensor 22. In the embodiment to be described, the slit width of the rotary encoder is 300 dpi, and the number of outputs of the photosensor 22 is 1 channel. However, the slit width and the number of outputs of the photosensor 22 are not particularly limited. For example, an image of 1200 dpi may be obtained by multiplying the slit width of 300 dpi by 4.

  FIG. 4 is a diagram showing circuit blocks relating to ink ejection control of the inkjet printer 10 according to the present embodiment. The ink jet printer 10 shown in FIG. 4 includes an ASIC 110 as a control device according to the present embodiment. Connected to the ASIC 110 are a photo sensor 22 of the rotary encoder 30a and a host interface (hereinafter referred to as a host I / F) 102 for controlling communication with an external host device. The ASIC 110 is connected to the heads H <b> 1 to H <b> 8 of the recording head 36, and further connected to a piezo driver 120 that is a driving unit for driving the piezo elements of the recording head 36.

  The ASIC 110 includes a CPU 112, an image processing unit 114, an ejection control unit 116, and a nonvolatile memory 118. The CPU 112 performs overall control of the inkjet printer 10. The image processing unit 114 develops image data on the memory based on a print command input via the host I / F 102 and converts the data into head data (nozzle data) for ejecting ink from each head. The ejection control unit 116 controls ink ejection from each head of the recording head 36 based on the head data converted by the image processing unit 114. The nonvolatile memory 118 stores various setting parameters.

  A typical printing operation in the inkjet printer 10 is realized by cooperatively controlling image processing for generating image data and ink ejection control based on a printing command from an external host device. Under the control of the CPU 112, the image processing unit 114 analyzes the received print command from the printer driver on the external host device and develops the image on the memory, thereby generating head data to be output from the recording head. . The ejection control unit 116 performs ink ejection control based on the head data input from the image processing unit 114 while analyzing the output signal from the photosensor 22. By such cooperative control, it is possible to eject ink droplets from the nozzles while positioning the recording head 36 in the transport direction with respect to the recording medium and land ink droplets of a desired size at a desired landing position.

  In such a line head type inkjet printer 10, there is a possibility that ink is ejected from a large number of nozzles at the same time, so a large amount of power may be required instantaneously. Such an instantaneous increase in power consumption causes various problems such as an increase in the size of the power supply circuit and the drive circuit of the recording head 36, image quality deterioration due to heat generation and voltage drop, and system abnormality. It is desired to suppress a decrease in ejection performance and productivity (printing throughput) while preventing such an increase in maximum power consumption.

  Therefore, in the inkjet printer 10 according to the present embodiment, the head array of the recording head 36 is divided into a plurality of systems, and the ink ejection timing for ejecting ink from the nozzles is set for each system, and the set ink ejection is set. A configuration is adopted in which the ink discharge speed is set according to the timing. In particular, the ink ejection speed is set slower for a system with a faster ejection timing, and the ink ejection speed is set faster for a system with a later ejection timing. Thereby, without dropping the transport speed, ink droplets are landed at a desired landing position with high accuracy, thereby ensuring ejection accuracy.

  Hereinafter, the ink ejection control of the inkjet printer 10 according to the present embodiment will be described in more detail with reference to FIG. In the embodiment shown in FIG. 4, the head array of the recording head 36 is divided into two systems, and the first ejection control unit 116-1 and the second ejection control unit 116-2 correspond to the two systems. Are provided. The first discharge control unit 116-1 is in charge of the downstream head group (H1, H3, H5, H7) installed downstream in the transport direction, and the second discharge control unit 116-2 is upstream in the transport direction. Is in charge of the upstream head group (H2, H4, H6, H8) installed in. Corresponding to the two systems, two piezo drivers 120 for driving the piezo elements of the head are also provided, the first piezo driver 120-1 and the second piezo driver 120-2.

The first discharge control unit 116-1 synchronizes with the output of the above-described photosensor 22, and outputs a common drive signal V _COM1 for driving the piezoelectric element that is a piezoelectric element via the first piezoelectric driver 120-1. In addition to outputting to the downstream head group (H1, H3, H5, H7), a head control signal for controlling ink ejection from the head is output to the downstream head group. Similarly, the second ejection control unit 116-2 outputs a common drive signal _VCOM2 to the upstream head group (H2, H4, H6, H8) via the second piezo driver 120-1 and ink from the head. A head control signal for controlling ejection is output. For the gradation of ink droplets ejected from each nozzle of the recording head 36, a drive pulse included in the common drive signal _VCOM1 , 2 is selected based on the head control signal, and a head drive output signal for each nozzle is output. Is controlled by.

In the embodiment to be described, the ink discharge timing for each system is set as a delay time, and the ink discharge speed is set as the crest value (amplitude) of the common drive signals V _COM1 and V _COM2 . The ink discharge speed of each of the discharge controllers 116 is delayed by a predetermined delay time from a system in which the discharge timing is slower (that is, on the premise that the ink discharge speed is the same in both systems). Is set to be faster. That is, by increasing the amplitude of the drive signal of a system that has a delay with respect to one system, the ink droplet ejection speed is increased by the amount that the ink droplet is ejected with a delay. Configured to land on position.

It is determined by the manufacturer or the user by simulation, experiment, test print, etc., how much time delay is set and how much the amplitude of the common drive signals V _COM1 and V _COM2 is changed is optimal. Can do. In a specific embodiment, the delay time and the peak value of the common drive signal can be set in the register of each ejection control unit 116 as a fixed parameter based on, for example, an evaluation performed in advance by experiment or simulation. With this configuration, it is possible to set the ink discharge timing and the ink discharge speed without adding parts. Alternatively, in a specific embodiment, the delay time and the peak value of the common drive signal are read from parameters stored in the nonvolatile memory 118 in advance by process inspection or initial setting by the user, and set in the registers of the respective discharge control units 116. You can also By configuring in this way, it becomes possible to set data that takes into account individual variations, and the quality can be stabilized.

In addition, the waveforms of the common drive signals V _COM1 and V _COM2 output from the piezo drivers 120-1 and 120-2 for driving the piezoelectric element are typically specified in the print mode (speed-oriented mode or image-oriented mode). ) And the type of recording medium (designation of plain paper or glossy paper, etc.), it may be used properly from among a plurality of types, or the amplitude of the drive waveform may be adjusted depending on the environmental temperature etc. . In the waveform selection control, the CPU 112 selects drive waveform data according to the received print job request from among a plurality of drive waveform data defining the respective waveforms stored in the ROM. When the drive waveform data is selected, the CPU 112 transfers the corresponding drive waveform data to each ejection control unit 116. The common drive signal having different peak values may be generated by changing the amplitude of the signal based on the same drive waveform data by the gain of the amplifier circuit, or driving waveform data having different peak values may be selected. May be generated.

  FIG. 5 is a diagram illustrating an example of an image output by a line head type inkjet printer. FIG. 6 is a diagram for explaining the relationship between (A) ink ejection timing and (B) power of the head when an image as shown in FIG. 5 is output from a conventional inkjet printer. On the other hand, FIG. 7 illustrates the relationship between (A) ink ejection timing and (B) power of the recording head 36 when the image as shown in FIG. 5 is output from the inkjet printer 10 according to the present embodiment. It is a figure to do. In the timing charts (A) shown in FIG. 6 and FIG. 7, ink ejection is performed during a period when the signal of each nozzle row is high (H).

  In the example shown in FIG. 5, the nozzles H1 to H8 of the recording head 36 are arranged in the order of black (K), cyan (C), yellow (Y), and magenta (M) from the upstream side in the transport direction. Are arranged. In FIG. 5, the nozzle rows are indicated by hatching, but each nozzle row is composed of a plurality of nozzles. Here, the interval between the nozzle rows in each head is N. In addition, as shown in FIG. 5, each area constituting the main scanning line of the width of the recording paper is shared by the eight heads H1 to H8, and the printing area is the nozzle of the first head in the main scanning direction. The area in charge of the row H1- * (* represents K, C, Y, M. The same applies hereinafter), the area in charge of the nozzle row H2- * of the second head,... The nozzle row H8- * is divided into eight regions such as a region in charge. The upstream head group (H2, H4, H6, H8) and the downstream head group (H1, H3, H5, H7) are displaced in the transport direction. Here, the interval in the transport direction between the black nozzle row (for example, H1-K) of the downstream head group and the magenta nozzle row (for example, H2-M) of the upstream head group is H.

  The image data 200 shown in FIG. 5 includes two sets of four lines of the width of the recording paper formed in the order of black, cyan, yellow, and magenta with a nozzle interval N in the head, and the magenta of the first set. A line and a subsequent second set of black lines are formed with an inter-head nozzle spacing H. When the image data 200 as shown in FIG. 5 is printed out from a conventional ink jet printer, as shown in FIG. This is exactly the timing when the upstream head group is positioned on the upper four lines and the downstream head group is positioned on the lower four lines. This momentary increase in power consumption due to simultaneous driving of multiple heads leads to an increase in the size of the power supply circuit and head drive circuit to withstand this power, leading to image quality degradation and system abnormalities due to heat generation and voltage drop. there's a possibility that.

  On the other hand, in the inkjet printer 10 according to the present embodiment, the timing of outputting the ejection signals of the nozzle groups (H2- *, H4- *, H6- *, H8- *) of the upstream head group is the downstream head group. Is delayed by time t with respect to the timing of outputting the ejection signals of the nozzle groups (H1- *, H3- *, H5- *, H7- *). Therefore, even when the image data 200 as shown in FIG. 5 is printed out, the number of heads that simultaneously eject ink is reduced. As a result, as shown in the graph shown in FIG. 7B, the power consumption is smoothed, and the instantaneous peak power consumption can be reduced.

On the other hand, for the nozzle groups (H2- *, H4- *, H6- *, H8- *) of the upstream head group in which the discharge signal output timing is delayed by time t, common driving with a large crest value is performed. The signal V _COM2 is applied. As a result, the ink ejection speed is increased corresponding to the delay time t, and the ink can be landed on the intended position of the recording paper.

  FIG. 8 is a flowchart showing a control method executed by the ink jet printer 10 according to the present embodiment. The control shown in FIG. 8 is started from step S100 in response to the power supply to the inkjet printer 10 being turned on. In step S101, the inkjet printer 10 executes a startup process for starting printing. For example, various setting values are read and a cleaning operation is performed.

  In step S <b> 102, the CPU 112 reads the delay time for each head and the amplitude of the common drive signal and sets them for each ejection control unit 116. In step S103, each ejection control unit 116 holds the delay time t for each head set by the CPU 112 and the amplitude of the common drive signal in a register. The CPU 112 constitutes a discharge timing setting unit and a discharge speed setting unit in the present embodiment. The delay time for each head and the amplitude of the common drive signal are defined in advance according to the arrangement of the head array. Here, for the downstream head group (H1, H3, H5, H7) arranged downstream, the delay time 0 and the peak value are set small, and the upstream head group (H2, H4, H6) arranged upstream. , H8), a delay time t and a peak value are set.

In step S104, the CPU 112 determines whether there is a print command. If it is determined in step S104 that there is a print command (YES), the process proceeds to step S105. In step S105, the CPU 112 receives a print command from the host I / F 102. In step S106, the image processing unit 114 converts the print command into head data. In step S107, each ejection control unit 116 outputs a head control signal to each head based on the converted head data, the delay time set for each system, and the amplitude of the common drive signal, and the piezo driver 120. The common drive signal _VCOM is output via.

  In step S108, the CPU 112 determines whether printing has ended. If it is determined in step S108 that printing has not yet ended (NO), the process returns to step S105 to continue receiving a print command. On the other hand, if it is determined in step S108 that printing has ended (YES), the process branches to step S109. Referring to step S104 again, if it is determined in step S104 that there is no print command yet (NO), the process branches to step S109.

  In step S109, the CPU 112 determines whether there is an instruction to turn off the power. If it is determined in step S109 that the power-off instruction has not yet been received (NO), the process returns to step S104 to wait for a print command. On the other hand, if it is determined in step S109 that power-off has been instructed (YES), the process is branched to step S110 and the process is terminated.

  As described above, according to this embodiment, the maximum power consumption of the ink ejection device can be reduced while reducing the influence on the productivity and the ejection performance, and the ink ejection device, the control device, and the ink ejection control. A method can be provided.

  With the above configuration, it is possible to set the ink discharge timing and the ink discharge speed for each nozzle row, and by setting a faster ink discharge speed for the nozzle row whose discharge timing is set later, the transport speed is lowered. Therefore, it is possible to ensure the discharge accuracy. As a result, the maximum power consumption of the ink ejection device can be reduced while reducing the influence on productivity and ejection performance.

  In the above-described embodiment, the head array of the recording head 36 has a first nozzle (discharge port) group (for example, H2-K, H4-K, H6-K, etc.) for a certain color (for example, black (K)). H8-K) and one or more head groups (H2, H4, H6, H8) arranged on the upstream side and a second nozzle group (for example, H1-K, H3-K, H5-K, H7-). K) and one or more head groups (H1, H3, H5, H7) arranged on the downstream side. However, the configuration of the recording head 36 is not particularly limited. In the above-described embodiment, the timing of outputting the ejection signal of the nozzle group of the upstream head group is delayed with respect to the nozzle group of the downstream head group. However, the present invention is not limited to this.

  In the embodiments described above, the ink jet printer 10 is used as the ink ejecting apparatus. However, the ink ejecting apparatus is not limited to the printer, and an ink jet system having an image forming function such as a copy function and a facsimile function. Other image forming apparatuses may be used. In the present embodiment, “imaging” refers to forming an image by applying ink droplets containing color materials such as pigments and dyes to a recording medium, but is not limited to such an example. In another embodiment, in addition to an ink containing a color material, an ink droplet containing an organic, inorganic or metal conductive material, semiconductor material, insulating material, light emitting material, carrier transport material, dye, DNA, etc. The present invention may be applied to any apparatus provided with an ink discharge mechanism that forms a desired pattern by landing ink droplets on necessary positions on a substrate such as glass, resin, or cloth. In addition, the ink jet method is not limited to the piezo method using a piezoelectric element as a driving device as long as the above-described effects are achieved.

  The functional unit can be realized by a computer-executable program written in a legacy programming language such as an assembler, C, C ++, C #, Java (registered trademark), an object-oriented programming language, or the like. ROM, EEPROM, EPROM , Stored in a device-readable recording medium such as a flash memory, a flexible disk, a CD-ROM, a CD-RW, a DVD-ROM, a DVD-RAM, a DVD-RW, a Blu-ray disc, an SD card, an MO, or through an electric communication line Can be distributed. In addition, a part or all of the functional unit can be mounted on a programmable device (PD) such as a field programmable gate array (FPGA) or mounted as an ASIC (application-specific integration). Circuit configuration data (bit stream data) downloaded to the PD in order to implement the above functional unit on the PD, HDL (Hardware Description Language) for generating the circuit configuration data, VHDL (VHSIC (Very High Speed) Integrated Circuits) Hardware Description Language)), data described in Verilog-HDL, etc. can be distributed by a recording medium.

  Although the embodiments of the present invention have been described so far, the embodiments of the present invention are not limited to the above-described embodiments, and those skilled in the art may conceive other embodiments, additions, modifications, deletions, and the like. It can be changed within the range that can be done, and any embodiment is included in the scope of the present invention as long as the effects of the present invention are exhibited.

DESCRIPTION OF SYMBOLS 10 ... Inkjet printer, 12 ... Paper feed tray, 14 ... Paper discharge tray, 16 ... Paper feed roller, 18 ... Separation pad, 20 ... Conveyance belt, 22 ... Photo sensor, 24 ... Conveyance guide, 26 ... Tip pressure roller 28 ... Charging roller, 30 ... Conveying roller, 30a ... Rotary encoder, 32 ... Tension roller, 34 ... Guide member, 36 ... Recording head, 38 ... Ink supply tube, 42 ... Separation claw, 44 ... Discharge roller, 46 DESCRIPTION OF SYMBOLS ... Paper discharge roller, 48 ... Double-sided paper feeding unit, 50 ... Head tank, 102 ... Host I / F, 110 ... ASIC, 112 ... CPU, 114 ... Image processing part, 116 ... Discharge control part, 118 ... Non-volatile memory, 120: Piezo driver, 200: Image data, Hx (x = 1-8) ... Head, Hx- * (x = 1-8; * = K, C, Y, M) ... Nozzle array

Japanese Patent No. 4285534 JP 2013-193284 A

Claims (9)

Head means including a first outlet group and a second outlet group;
Discharge timing setting means for setting an ink discharge timing for each of the first discharge port group and the second discharge port group;
Discharge speed setting means for setting an ink discharge speed corresponding to the set ink discharge timing for each of the first discharge port group and the second discharge port group, and the first discharge port group The set ink discharge timing is later than the ink discharge timing set for the second discharge port group, and the ink discharge speed set for the first discharge port group is the second discharge port. An ink discharge apparatus characterized by being faster than an ink discharge speed set for a group. The ink ejection speed is controlled by a drive signal for a drive element that ejects ink from each ejection port, and the ink ejection device includes:
First driving means for outputting a first driving signal to the first ejection port group;
2. The second drive means for outputting a second drive signal different from the first drive signal output to the first discharge port group to the second discharge port group. Ink ejection device.   The ink ejection apparatus according to claim 1 or 2, wherein the ink ejection timing and the ink ejection speed for each ejection port group are written in the register as fixed parameters.   The ink ejection apparatus according to claim 1, further comprising a non-volatile storage unit that stores data defining an ink ejection timing and an ink ejection speed for each ejection port group.   The ink discharge timing is defined as a delay time from a reference time when the ink discharge speeds of the first discharge port group and the second discharge port group are the same. The ink ejection device according to claim 1.   The head means includes one or more first arrangement heads constituting the first ejection port group for a certain color and one or more second arrangement heads constituting the second ejection port group for the certain color. The one or more first arrangement heads and the one or more second arrangement heads are responsible for each area constituting a main scanning line for the certain color, and the first arrangement heads are arranged in the first arrangement. The ink ejection device according to claim 1, wherein the head and the head in the second arrangement are displaced in the transport direction. A control device for controlling head means including a first discharge port group and a second discharge port group,
Discharge timing setting means for setting an ink discharge timing for each of the first discharge port group and the second discharge port group;
Discharge speed setting means for setting an ink discharge speed corresponding to the set ink discharge timing for each of the first discharge port group and the second discharge port group, and the first discharge port group The set ink discharge timing is later than the ink discharge timing set for the second discharge port group, and the ink discharge speed set for the first discharge port group is the second discharge port. A control device characterized by being faster than an ink discharge speed set for a group. The ink discharge speed is controlled by a drive signal for a drive element that discharges ink from each discharge port, and the control device includes:
First control means for controlling the first ejection port group to output a first drive signal;
2. A second control unit that controls the second discharge port group to output a second drive signal different from the first drive signal output to the first discharge port group. 8. The control device according to 7. An ink discharge control method for controlling a head unit including a first discharge port group and a second discharge port group, wherein the control unit includes:
An ejection timing setting step for setting an ink ejection timing for each of the first ejection port group and the second ejection port group;
A discharge speed setting step for setting an ink discharge speed corresponding to a set ink discharge timing for the first discharge port group and the second discharge port group, respectively. The set ink discharge timing is later than the ink discharge timing set for the second discharge port group, and the ink discharge speed set for the first discharge port group is the second discharge port. An ink discharge apparatus characterized by being faster than an ink discharge speed set for a group.