JP2022187817A - Liquid discharge device and linear medium processing system - Google Patents

Abstract

To provide a liquid discharge device capable of efficiently discharging a liquid.SOLUTION: The liquid discharge device comprises: a liquid discharge surface having a plurality of liquid discharge ports; and a control unit that generates a drive waveform and controls discharging of a liquid from the liquid discharge ports on the basis of the drive waveform. The control unit is provided with a plurality of droplet number distribution tables in which droplet discharge frequency information for each liquid discharge port is set, and forms the drive waveform by using the droplet number distribution table selected from among the droplet number distribution tables on the basis of use environment information of the liquid discharge ports acquired before the discharge operation start of the liquid.SELECTED DRAWING: Figure 9

Description

The present invention relates to a liquid ejection device and a linear medium processing system.

Japanese Patent Laid-Open No. 2004-100000 discloses a liquid droplet ejecting means 44 that performs ejection control so that droplets of an amount based on image data are ejected from a nozzle, targeting positions on a medium corresponding to pixel positions of image data, and a plurality of liquid droplet ejection means 44 . recording means 71 for recording, for each nozzle, the number of times droplet ejection control has been performed for at least some of the nozzles; An amount larger than the amount based on the image data, targeting the positions on the medium corresponding to the pixel positions of the image data where ejection control was performed so that ejection was performed from nozzles for which ejection control was performed less than N times. discloses a droplet ejection device 20 that performs ejection control so as to eject droplets of .

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid ejection device capable of efficiently discharging liquid.

The present invention provides a liquid ejection apparatus comprising a liquid ejection surface having a plurality of liquid ejection ports, and a control section that generates a drive waveform and controls ejection of liquid from the liquid ejection ports based on the drive waveform. The control unit includes a plurality of droplet number distribution tables in which droplet ejection frequency information is set for each of the liquid ejection ports, and based on usage environment information of the liquid ejection ports acquired before the start of the liquid ejection operation, the plurality of liquid ejection ports. The drive waveform is formed using a droplet number distribution table selected from the droplet number distribution table of .

According to the present invention, it is possible to provide a liquid ejection device capable of efficiently ejecting liquid.

1 is an overall schematic diagram of a linear medium processing system according to the present invention; FIG. 1 is a schematic configuration diagram of a liquid ejection unit according to the present invention; FIG. FIG. 4 is an explanatory diagram of the nozzle surface of the liquid ejection head; FIG. 4 is an explanatory diagram of the head position in the head movement direction; Explanatory drawing which shows an example of an ejection sensor. FIG. 5 is an explanatory diagram showing a state in which overprinting is performed on a linear medium; Explanatory drawing which shows the relationship between a nozzle position and a thickening speed. Conceptual diagram of droplet number distribution. Explanatory drawing which shows an example of the number-of-drops distribution table. FIG. 2 is a hardware block diagram of the embroidery system according to the present invention; FIG. 4 is a flow chart from print image determination to droplet ejection. FIG. 10 is a flowchart of a droplet number distribution table determination process;

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall schematic diagram of a linear media processing system according to the present invention.

An embroidery system 100 is shown here as an example of a linear media processing system. Embroidery system 100 includes supply reel 102 , liquid dispensing unit 103 , drying unit 104 , post-processing unit 105 and embroidery unit 106 .

The supply reel 102 holds embroidery thread 101 (hereinafter referred to as thread) and supplies the thread 101 to the liquid ejection unit 103 . Rollers 108 and 109 are provided between the supply reel 102 and the liquid ejection unit 103 . The roller 109 includes a rotary encoder 405 including an encoder wheel 405b provided coaxially with the roller 109 and an encoder sensor 405a for reading an encoder slit provided in the encoder wheel 405b. The conveying state of the yarn 101 is detected by this rotary encoder 405 .

The liquid ejection unit 103 includes a liquid ejection head 1 (hereinafter referred to as head) and a maintenance unit 2 , and the head 1 applies liquid to the thread 101 passing below the head 1 . In this embodiment, the head 1 is a head that employs an inkjet recording method, and the liquid applied to the threads 101 is mainly colored ink. The maintenance unit 2 includes an idle ejection receiving section, a wiping section, a suction section, and the like, and these sections perform various processes on the head 1 when the head 1 is positioned at each section, thereby improving the liquid ejection performance of the head 1. maintain.

The drying unit 104 includes heating means, and heats and dries the yarn 101 after the ink has been applied. As a result, the thread 101 becomes a thread dyed in a desired color.

The post-processing unit 105 includes cleaning means for washing the yarn 101 by removing the coloring material remaining unfixed on the yarn 101, lubricant application means for applying a lubricant such as wax to the surface of the yarn 101, and the like. Arrange 101 conditions.

The embroidery unit 106 has an embroidery head, sews the dyed thread 101 into the cloth, and embroiders patterns such as patterns and patterns on the cloth.

In the above configuration, the rotary encoder 405 detects the transport speed of the thread 101 taken in by the embroidery unit 106 , and the liquid ejection unit 103 controls ink ejection from the head 1 according to the transport speed of the thread 101 . That is, when the conveying speed of the thread 101 taken in by the embroidery unit 106 is slow, the frequency of ejecting ink onto the thread 101 is lowered. Further, when the conveying speed of the thread 101 taken in by the embroidery unit 106 is high, the frequency of ejecting ink onto the thread 101 is increased. Accordingly, the liquid ejection unit 103 can dye the thread 101 in synchronization with the transport speed of the thread 101 taken in by the embroidery unit 106 .

When dyeing the thread 101, a wide range of colors can be expressed by combining colors (for example, black, cyan, magenta, and yellow) in the same manner as printing on paper with an inkjet printer.

Here, the thread 101 is an example of a linear medium. “Yarn” means glass fiber yarn, wool yarn, cotton yarn, synthetic yarn, metal yarn, mixed yarn of wool, cotton, polymer or metal, yarn, filament, or any linear object capable of applying liquid, braided cord , including flat cords.

In addition to the above-mentioned linear objects, other than the linear objects, examples of ejection receiving media that can be dyed with liquid droplets include belt-shaped members (continuous substrates) to which liquid can be applied, such as ropes, cables, and cords. . Each of the ejection receiving media is a linear or belt-like medium having a narrow width and continuous in the transport direction.

Note that the linear medium processing system is not limited to the embroidery system 100 . For example, instead of the embroidery unit 106, another processing device such as a weaving machine or a sewing machine may be provided after the post-processing unit 105. FIG. If the embroidery unit is installed in another location (not of the in-line type), a winding unit that winds the yarn after dyeing may be provided after the post-processing unit 105 instead of the embroidery unit 106. . In this case, the once wound yarn is transported to the place where the processing device is installed, the yarn is loaded into the processing device, and the desired processing is performed.

FIG. 2 is a schematic configuration diagram of the liquid ejection unit according to the present invention, and supplements the description of the liquid ejection unit 103 shown in FIG.

The liquid ejection unit 103 includes a plurality of heads 1a, 1b, 1c, and 1d arranged in tandem along the yarn conveying direction. The heads 1a to 1d eject inks of different colors. For example, the head 1a ejects black (K) ink, the head 1b cyan (C) ink, the head 1c magenta (M) ink, and the head 1d yellow (Y) ink. It is a head that ejects droplets.

Note that the order of colors is an example, and the colors may be arranged in a different order. Also, the number of heads is not limited to four, and the number of heads may be increased or decreased according to the number of colors to be mounted.

An environment sensor 514 is provided between the head 1b and the head 1c, and the environment sensor 514 detects the temperature and humidity near the nozzles of the head 1. FIG.

The location where the environment sensor 514 is installed is an example, and the environment sensor 514 may be installed on the right side of each of the heads 1a to 1d, for example.

Further, the liquid ejection unit 103 includes a plurality of maintenance units 2a, 2b, 2c, and 2d below the heads 1a to 1d with the transport path of the yarn 101 interposed therebetween. The maintenance units 2a to 2d each have an idle discharge receiving section, a wiping section, a suction section, and the like, and perform various processes on the heads 1a to 1d located in each section.

FIG. 3 is an explanatory diagram of the nozzle surface of the liquid ejection head, and is a view of the head 1 of the liquid ejection unit 103 as seen from below.

The heads 1 a to 1 d provided in the liquid ejection unit 103 have a nozzle surface 12 facing the thread 101 . Each nozzle surface 12 of the heads 1a to 1d is provided with two nozzle rows 10a and 10b, and each nozzle row 10a and 10b is formed from a nozzle group in which a plurality of (eight in this example) nozzles 11 are arranged in the yarn conveying direction. Become. Here, the nozzle 11 is an example of a liquid ejection port, and the nozzle surface 12 is an example of a liquid ejection surface.

The nozzle row 10a and the nozzle row 10b are arranged parallel to the yarn conveying direction with a predetermined distance therebetween in a direction perpendicular to the yarn conveying direction (head moving direction). When the yarn 101 is to be dyed, the heads 1a to 1d are moved so that the nozzle row 10a or the nozzle row 10b of the heads 1a to 1d is positioned right above the yarn 101. FIG. As a result, the heads 1a to 1d eject ink onto the yarn 101 moving in the yarn conveying direction to apply the ink to the yarn 101 (FIG. 3 shows the case of dyeing the yarn 101 using the nozzle row 10a). there).

The nozzle rows 10a and 10b move the heads 1a to 1d in the head movement direction when a predetermined timing obtained from the usage time, the ink discharge amount, etc. is reached, and the nozzle rows 10a and 10b move against the yarn 101. The nozzle row 10b is exchanged.

FIG. 4 is an explanatory diagram of the head position in the head movement direction.

The liquid ejection unit 103 includes a maintenance unit 2 below the head 1 with the transport path of the thread 101 interposed therebetween. The maintenance unit 2 has a suction cap 21 on its upper portion, and the suction cap 21 can move back and forth with respect to the maintenance unit 2 (movement in the direction of arrow A in FIG. 4(a)). As a result, the suction cap 21 can be brought into contact with and separated from the nozzle surface of the head 1 .

The maintenance unit 2 also has a discharge sensor 513 on its upper portion. The ejection sensor 513 detects whether the nozzle row 10a (or nozzle row 10b) of the head 1 is ejecting ink droplets. Details of the ejection sensor 513 will be described with reference to FIG.

The head 1 located above the maintenance unit 2 is movable relative to the maintenance unit 2 in the head movement direction. FIG. 4A shows a state in which the nozzle row 10a of the head 1 is positioned directly above the yarn 101, and the nozzle row 10a ejects ink toward the yarn 101 to dye the yarn 101. FIG. FIG. 4B shows a state in which the nozzle row 10b of the head 1 is positioned directly above the yarn 101, and the nozzle row 10b ejects ink toward the yarn 101 to dye the yarn 101. FIG.

FIG. 4C shows a state in which the head 1 is positioned facing the suction cap 21 . When the head 1 moves to a position facing the suction cap 21, the suction cap 21 moves toward the head 1 (raised in this embodiment) to cover (cap) the nozzle surface of the head 1, thereby drying the nozzle surface. prevent. Further, the suction cap 21 performs suction on the nozzles while capping the nozzle surface, thereby preventing ejection failure due to ink clogging in the nozzles.

The maintenance unit 2 includes, in addition to the suction cap 21, a wiping unit and an idle discharge receiver (not shown). The wiping unit includes a wiper member that wipes the nozzle surface of the head 1 while moving relative to the nozzle surface in the head movement direction. Further, the blank ejection receiving section includes a collection container for receiving ink ejected from the nozzles when blank ejection (idle shot) is performed on the nozzles that are not used for applying ink to the yarn 101 .

FIG. 5 is an explanatory diagram showing an example of an ejection sensor.

The ejection sensor 513 is positioned below the head 1 and includes a light emitting portion 513a and a light receiving portion 513b. The light-emitting portion 513a includes, for example, a semiconductor laser that emits laser light, and the light-receiving portion 513b includes an optical sensor that receives the laser light from the light-emitting portion 513a and outputs a signal indicating the light-receiving state.

In the above configuration, before starting the ink ejection operation onto the yarn 101, ink droplets are sequentially ejected from each nozzle 11 (eight nozzles 1ch to 8ch in this example) forming the nozzle row 10a (or nozzle row 10b) of the head 1. A discharge operation is performed. Of the arrows shown at each nozzle position, the solid arrow indicates that the ink droplets are correctly ejected, and the broken arrow indicates that the ink droplets are not ejected.

Of the 8 nozzles (8 channels), the 1ch and 2ch nozzles do not eject ink droplets, so there is no change in the laser light detected by the light receiving unit 513b, and the ejection sensor 513 does not detect ink droplets.

Since the nozzles of 3ch to 8ch are ejecting ink droplets, each ink droplet sequentially enters the laser beam of the ejection sensor 513 and momentarily interrupts the optical path. Thereby, the light receiving portion 513b detects that the ink droplet crosses the laser beam, and the discharge sensor 513 detects the discharge of the ink droplet.

As described above, it is checked whether there is a non-ejecting nozzle before starting the ink ejection operation for the yarn 101, and if there is a non-ejecting nozzle, the dyeing of the yarn 101 is not started, and the maintenance unit 2 is operated. A state in which ink can be ejected is made by performing blank ejection or the like.

FIG. 6 is an explanatory diagram showing a state in which overprinting is performed on a linear medium.

The yarn 101 moves along the nozzle rows 10a of the head 1 in the yarn transport direction. The nozzle 11 ejects ink droplets onto the yarn 101 moving in the yarn conveying direction to dye the yarn 101 in a desired color.

In dyeing, a desired density (gradation) is expressed by superimposing ink droplets on one pixel to be dyed (hereinafter referred to as a target pixel). For example, when expressing a target pixel at 100% density, all the nozzles 11 forming the nozzle row 10a are used, and 100 ink droplets are ejected from each nozzle 11 (100 times). When expressing the target pixel at 50% density, 50 ink droplets (50 times) are ejected from each nozzle 11 forming the nozzle row 10a.

In other words, in the present embodiment, a pixel is a unit of an area in which ink droplets are overstrike for gradation expression. In this manner, the number of overlapping ink droplets for the target pixel is determined according to the density (gradation) desired to be expressed.

Therefore, when the target pixel is expressed at a low density, not all the nozzles 11 of the nozzle row 10a are used as shown in the figure, and some nozzles 11 of the nozzle row 10a may be sufficient.

As described above, if the number of nozzles to be used differs depending on the gradation to be expressed, the nozzles that are not used tend to dry out, and ejection failures due to ink clogging in the nozzles tend to occur. In addition to the frequency of use of nozzles, the easiness of ink drying (viscosity thickening speed) varies depending on the environment around the head. The relationship between the nozzle position and the ease of ink drying (viscosity increasing speed) will be described below.

FIG. 7 is an explanatory diagram showing the relationship between the nozzle position and the thickening speed. For simplicity of explanation, the number of nozzles 11 forming the nozzle row 10a (or nozzle row 10b) is six (six channels).

The head 1 provided in the liquid ejection unit 103 is affected by air currents around the head, uneven temperature and humidity, and the structure of the ink flow path inside the head. Viscosity velocity may vary.

The figure shows an example of a case where the thickening speed tends to be faster on the No. 1 nozzle side of the head 1 than on the No. 6 nozzle side. In this case, if the total number of droplets required for overprinting on the target pixel is distributed so that the number of droplets for the 1st and 2nd nozzles is larger than the number of droplets for the 3rd to 6th nozzles, the The ink in the state can be efficiently discharged while being used for dyeing the yarn.

FIG. 8 is a conceptual diagram of droplet number distribution.

FIG. 8(a) is an explanatory diagram showing an example of criteria for distributing the number of drops. The horizontal axis indicates the number (position) of the nozzles 11 forming the nozzle row 10a (or nozzle row 10b) of the head 1, and the vertical axis indicates the number of ejected droplets.

In this example, when 150 droplets (150 times) are applied to the target pixel by each nozzle, that is, a total of 900 droplets (150 droplets x 6 nozzles) are overprinted, a solid image with a density of 100% is printed on the target pixel. It represents forming an image.

FIG. 8B is an explanatory diagram showing an example of distribution of the number of ejected droplets when an image with a density of 60% is formed on the target pixel by the head having the viscosity increasing speed tendency shown in FIG.

The total number of droplets required to form an image with a density of 60% on the target pixel is 540 droplets. However, the No. 1 and No. 2 nozzles are in an environment where they dry more easily than the other nozzles, and the ink in the nozzles tends to increase in viscosity, easily causing ink clogging or the like.

Therefore, in this embodiment, the number of ink droplets to be ejected is distributed to each nozzle as shown in FIG. 8B based on the tendency of the viscosity increasing speed shown in FIG. For example, the No. 1 nozzle, which has a fast thickening speed, ejects 150 ink droplets, No. 2 nozzle ejects 115 droplets, No. 3 to No. 5 nozzles eject 75 droplets, and No. 6 nozzle ejects 50 ink droplets. Distribute.

FIG. 8(c) is an explanatory diagram showing drive waveforms for ejecting the number of droplets distributed in FIG. 8(b) from each nozzle. The drive waveforms for the second and subsequent nozzles are generated by electrically masking the drive waveform for the first nozzle based on the ratio of the number of ejected droplets.

FIG. 9 is an explanatory diagram showing an example of the number-of-drops distribution table. FIG. 9A is an explanatory diagram showing the relationship between the ejected droplet number ratio and the nozzle position, and FIG. 9B is an explanatory diagram showing the relationship between the ejected droplet number and the nozzle position.

In the droplet number distribution of ink droplets, a plurality of droplet number distribution tables are prepared in advance in the control unit 500, which will be described later, and a droplet number distribution table is selected based on usage environment information acquired before starting the ink ejection operation. .

For example, consider the case of a head having a characteristic that drying tends to occur from the central portion of the nozzle row toward both ends. Assume that the total number of overprinted droplets for one pixel (target pixel) determined from the gradation is 600 droplets. In this case, the control unit 500 selects a drop number distribution table in which the ejected drop number ratio increases from nozzles 3 and 4 in the center toward both ends as shown in FIG. 9A. As a result, the number of droplets for each nozzle is determined as shown in FIG. 9(b).

FIG. 9B shows an example in which 600 ink droplets are superimposed on the target pixel, and 150 droplets are superimposed on the No. 1 and No. 6 nozzles located at both ends of the nozzle row. No. 2 and No. 5 nozzles perform superimposition of 100 droplets, and No. 3 and No. 4 nozzles perform superimposition of 50 droplets. This completes the superposition of 600 ink droplets onto the target pixel.

As described above, in the present embodiment, the nozzles at the ends, which are vulnerable to drying, shoot (eject) more than the nozzles at the center. Implementation frequency can be reduced.

As in the above example, when the total number of ink droplets (600 droplets) required for overprinting is greater than or equal to the number of nozzles (6), the droplet number distribution table allows each nozzle to is a droplet number distribution table that distributes the number of times of droplet ejection so as to eject ink.

On the other hand, there may be cases where the total number of ink droplets required for overprinting is less than the number of nozzles (5 droplets or less in the above example), such as when expressing a gradation of an extremely light color (low density) in the target pixel. . In this case, the droplet number distribution table is a droplet number distribution table that distributes the number of droplet ejections with priority given to nozzles that have not been used to eject ink for the immediately preceding pixel.

FIG. 10 is a hardware block diagram of an embroidery system according to the present invention.

The control unit 500 controls the entire embroidery system 100. The control unit 500 includes a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, and an NVRAM (Non-RAM). volatile RAM) 504 and an ASIC (Application Specific Integrated Circuit) 505 . The control unit 500 also includes an I/F (Interface) 506 , a head drive control unit 507 , a carriage control unit 508 and a data bus 509 .

The CPU 501 controls the overall operation, which also controls the movement of the heads 1a to 1d. The CPU 501 reads programs and data stored in the ROM 502 from the ROM 502 to the RAM 503 and executes processing.

A ROM 502 is a non-volatile semiconductor memory, and stores programs executed by the CPU and other fixed data (BIOS, OS settings, network settings, etc.). A RAM 503 is a volatile semiconductor memory that temporarily stores programs and data. The NVRAM 504 is a rewritable, non-volatile semiconductor memory that enables data retention when the device is powered off.

The ASIC 505 processes various signal processing for image data, image processing such as rearrangement, and input/output signals for controlling the entire apparatus. The I/F 506 transmits and receives data and signals to and from a host such as a PC (Personal Computer) 510 or the like.

The head drive control unit 507 includes a droplet number distribution table 507a and a drive waveform generation unit 507b. Based on the detection results of the ejection sensor 513 and the environment sensor 514, the head drive control unit 507 selects the droplet number distribution table to be used for dyeing the yarn from the droplet number distribution table 507a. Further, the head drive control unit 507 generates drive waveforms for driving the heads 1a to 1d in the drive waveform generation unit 507b based on the selected droplet number distribution table, and outputs drive waveform data and the like to the head driver 512. do.

A carriage control unit 508 drives the carriage motor 31 . An operation panel 511 inputs and displays necessary information. A head driver 512 ejects ink droplets from the heads 1 a to 1 d based on instructions from the head drive control unit 507 .

The ejection sensor 513 detects whether ink droplets are ejected from each nozzle 11 of the heads 1a to 1d, and outputs the detection result to the control unit 500. FIG. The environment sensor 514 detects the temperature and humidity near the nozzles of the heads 1a to 1d and outputs the detection result to the control unit 500. FIG.

The carriage motor 31 moves the carriage 30 based on instructions from the carriage control unit 508 . The rotary encoder 405 detects the transport state of the yarn 101 and outputs the detection result to the control section 500 .

A carriage 30 holds the heads 1a to 1d. By moving the carriage 30 in the head movement direction shown in FIG. 4, the heads 1a to 1d can move to a position facing the thread 101, a position facing the suction cap 21, and the like. Note that the carriage 30 is not limited to a single one. For example, a carriage may be individually provided for each head, and the movement operation in the head movement direction may be performed independently for each head.

The control unit 500 receives print data and the like generated by the PC 510 at the I/F 506 via a cable or network. Then, the CPU 501 of the control unit 500 reads out and analyzes the print data in the reception buffer provided in the I/F 506 .

The ASIC 505 performs necessary image processing, data rearrangement processing, and the like on the analysis result of the CPU 501 . The CPU 501 transmits the processing result of the ASIC 505 to the head drive control unit 507, and the head drive control unit 507 outputs image data and drive waveforms to the head driver 512 at predetermined timings.

The dot pattern data for image output may be generated by storing the dot pattern data in the ROM 502, for example. Alternatively, the host side (PC 510 ) may expand the image data into bitmap data and transmit the bitmap data to the embroidery system 100 .

A drive waveform generation unit 507b provided in the head drive control unit 507 includes a D/A converter and an amplifier for D/A (digital to analog) conversion of the drive pulse pattern data stored in the ROM 502 . Then, the drive waveform generator 507b outputs to the head driver 512 a drive waveform composed of one drive pulse or a plurality of drive pulses.

The head driver 512 selectively applies drive pulses forming a drive waveform from the drive waveform generator 507b to the pressure generating means of the head based on the serially input image data corresponding to one line of the head to rotate the head. drive. Note that the head driver 512 includes, for example, a shift register for inputting a clock signal and image data, a latch circuit for latching the register value of the shift register with a latch signal, a level shifter for changing the level of the output value of the latch circuit, and the level shifter. includes an analog switch array or the like that controls on/off with By controlling the on/off of the analog switch array, a predetermined drive pulse included in the drive waveform is selectively applied to the pressure generating means of the head.

FIG. 11 is a flow chart from print image determination to droplet ejection.

First, an image to be printed on the thread 101 is determined (step S1). That is, in step S1, the density (gradation) of each pixel (target pixel) is determined by determining the print image.

By determining the gradation, the number of droplets (total number of droplets) to be superimposed in the target pixel is determined (step S2).

Next, when the total number of droplets for overprinting is determined, a droplet number distribution table for distributing the number of ink droplets to be ejected from which nozzle is selected from a plurality of droplet number distribution tables and determined ( step S3).

Then, ink droplets are ejected from each nozzle based on the ejection droplet number ratio of the selected droplet number distribution table, and the target pixel is dyed with a desired gradation (step S4).

FIG. 12 is a detailed flowchart of the droplet number distribution table determination step (step S3) in the flow of FIG.

The droplet number distribution table 507a includes a plurality of patterns of droplet number distribution tables created based on usage environment information including information on ink thickening speed, information on non-ejection of ink from nozzles, and information on temperature and humidity in the vicinity of nozzles. Prepared in advance.

In each droplet number distribution table, information on the number of times ink droplets are ejected for each nozzle when the above usage environment information is assigned is set.

For example, the information on the viscosity increase speed of the ink includes information such as the ease of drying due to the structure of the nozzle, in addition to the characteristic values unique to the ink. In addition, information about non-ejection of ink from nozzles is information about nozzles that are unable to eject ink. Furthermore, the temperature/humidity information near the nozzles is information about the ease of drying for each nozzle that is expected from experimentally known in-machine airflow and temperature/humidity unevenness.

When entering the step of determining the number of drops distribution table, first, the head drive control unit 507 extracts a table based on the temperature and humidity using the temperature and humidity information detected by the environment sensor 514 (step S31). Thereby, the droplet number distribution table of the pattern corresponding to the temperature and humidity detected by the environment sensor 514 is extracted.

Next, the head drive control unit 507 performs a non-ejection check based on the ejection information detected by the ejection sensor 513 (step S32). Accordingly, the head drive control unit 507 determines whether ink can be ejected according to the pattern (ejection droplet number ratio) of the droplet number distribution table selected in step S31.

Here, when the head drive control unit 507 determines that there is a non-ejection nozzle that cannot eject ink, the maintenance unit 2 executes an idle ejection operation or the like to eliminate the non-ejection state of the nozzle.

When the head drive control unit 507 determines that there are no ejection failure nozzles, it performs a characteristic check on the nozzle structure (step S33).

In the heads 1a to 1d, the thickening speed of the ink in the nozzles differs depending on the nozzle position even within the same head due to the effects of air currents around the heads, uneven temperature and humidity, and the structure of the ink flow paths inside the heads. There is Therefore, in step S33, the values of the droplet number distribution table selected in step S31 are corrected in consideration of the characteristics that the nozzle structure described above causes the ink to thicken. This makes it possible to determine an optimized drop number distribution table.

Note that the order of steps S31 to S33 is an example, and is not limited to this order. Further, step S32 does not necessarily have to be performed in the droplet number distribution table determination process, and information acquired in another process such as before the start of the ink ejection operation to the thread may be used. Further, step S33 may be corrected in advance at the stage of storing in the droplet number distribution table 507a without being performed in the droplet number distribution table determination process.

As described above, the present embodiment includes the nozzle surface 12 having a plurality of nozzles 11, and the controller 500 that generates a driving waveform and controls the ejection of ink from the nozzles 11 based on the driving waveform. In the apparatus, the control unit 500 includes a plurality of droplet number distribution tables 507a in which information on the number of times droplets are ejected for each nozzle is set. A drive waveform is formed using a droplet number distribution table selected from the number distribution table.

As a result, it is possible to reduce the thickening of the ink inside the nozzle 11 and on the nozzle surface 12, and to efficiently discharge the ink in a state before thickening through the thread 101 while dyeing the thread 101. can be done. In addition, since the occurrence of thickened ink can be reduced, the frequency of the idle ejection operation in the maintenance unit 2 can be reduced, and the amount of ink discarded due to idle ejection can also be reduced.

Also, as described above, the droplet distribution table 507a is set based on the usage environment information of the nozzles 11 .

In addition, as described above, the usage environment information includes at least one of ink thickening speed information, non-ejection information of ink from the nozzles 11 , and temperature/humidity information in the vicinity of the nozzles 11 .

As a result, the droplet distribution table can be optimized according to the liquid ejecting apparatus to be used.

Further, as described above, in the case where ink is overstrike on the thread 101 and the total number of ink droplets required for the overstrike is equal to or greater than the number of nozzles 11, the droplet number distribution table is such that the nozzles 11 are A droplet number distribution table is used that distributes the number of droplet ejection times so that each ink is ejected one or more times.

Further, as described above, when ink is overstrike on the thread 101 and the total number of ink droplets required for overstrike is less than the number of nozzles 11, the droplet number distribution table A droplet number distribution table is used in which the number of droplet ejections is distributed with priority given to nozzles that were not used in the operation, ie, the ink overprinting for the immediately preceding pixel.

As a result, the occurrence of thickened ink inside the nozzles 11 can be reduced.

In this embodiment, an example of an embroidery system has been described. It can also be applied to systems that apply liquid.

What has been described above is only an example, and the present invention has specific effects in each of the following aspects.

[First aspect]
A first aspect includes a liquid ejection surface (for example, nozzle surface 12) having a plurality of liquid ejection openings (for example, nozzles 11), and a drive waveform that generates liquid (for example, ink) from the liquid ejection openings based on the drive waveform. In a liquid ejection apparatus (eg, embroidery system 100) including a control section (eg, control section 500) that controls the ejection of liquid droplets, the control section controls a plurality of droplet ejection frequency information set for each liquid ejection port. A distribution table (for example, a droplet number distribution table 507a) is provided, and a droplet number distribution table selected from the plurality of droplet number distribution tables based on usage environment information of the liquid ejection port acquired before the start of the liquid ejection operation is used. and forming the driving waveform.

According to the first aspect, it is possible to provide a liquid ejection device capable of efficiently ejecting liquid.

[Second aspect]
A second aspect is characterized in that, in the first aspect, the droplet number distribution table (for example, the droplet number distribution table 507a) is set based on usage environment information of the liquid ejection port (for example, the nozzle 11). is.

[Third aspect]
A third aspect is the first aspect or the second aspect, wherein the usage environment information includes thickening speed information of the liquid (e.g., ink), non-ejection information of the liquid from the liquid ejection port (e.g., nozzle 11), and temperature/humidity information in the vicinity of the liquid ejection port.

According to the second aspect and the third aspect, the droplet number distribution table can be optimized according to the liquid ejection device to be used.

[Fourth aspect]
A fourth aspect is any one of the first to third aspects, wherein the liquid (for example, ink) is overprinted on the recording medium (for example, the thread 101), and the liquid required for the overprinting is When the total number of droplets is greater than or equal to the number of liquid ejection openings (for example, nozzles 11), the droplet number distribution table (for example, droplet number distribution table 507a) is configured so that each of the liquid ejection openings ejects the liquid one or more times. Second, a droplet number distribution table is provided in which the number of times of droplet ejection is distributed.

[Fifth aspect]
A fifth aspect is, in any one of the first to third aspects, a case where the liquid (for example, ink) is overprinted on the recording medium (for example, the thread 101), and the liquid required for the overprinting is When the total number of droplets is less than the number of the liquid ejection ports (for example, nozzles 11), the droplet number distribution table (for example, the droplet number distribution table 507a) gives priority to the liquid ejection ports that were not used in the previous overstrike operation. and a droplet number distribution table that distributes the number of times of droplet ejection.

According to the fourth aspect and the fifth aspect, it is possible to reduce the occurrence of thickened liquid inside the liquid ejection port.

1a, 1b, 1c, 1d liquid discharge heads 10a, 10b nozzle rows 11 nozzles (liquid discharge ports)
12 nozzle surface (liquid ejection surface)
500 control unit 507 head drive control unit 507a droplet number distribution table 507b drive waveform generation unit 513 ejection sensor 514 environment sensor

JP 2018-144337 A

Claims (6)

a liquid ejection surface having a plurality of liquid ejection ports;
A liquid ejecting apparatus comprising a control unit that generates a driving waveform and controls ejection of the liquid from the liquid ejection port based on the driving waveform,
The control unit
comprising a plurality of droplet number distribution tables in which droplet ejection frequency information for each liquid ejection port is set;
The driving waveform is formed using a droplet number distribution table selected from the plurality of droplet number distribution tables based on usage environment information of the liquid ejection port acquired before the start of the liquid ejection operation. discharge device. 2. The liquid ejecting apparatus according to claim 1, wherein said droplet number distribution table is set based on usage environment information of said liquid ejection port. The usage environment information includes at least one of information on the viscosity increase rate of the liquid, information on non-ejection of the liquid from the liquid ejection port, and information on temperature and humidity in the vicinity of the liquid ejection port. 3. The liquid ejection device according to claim 1 or 2. When the liquid is deposited onto a recording medium in multiple layers, and when the total number of droplets of the liquid required for the multiple deposition is equal to or greater than the number of the liquid ejection openings, the droplet number distribution table may include the liquid ejection openings. 4. The liquid ejection apparatus according to claim 1, further comprising a droplet number distribution table that distributes the number of droplet ejection times so that each of the liquid droplets is ejected one or more times. When the liquid is overstrike on the recording medium and the total number of droplets of the liquid required for the overstrike is less than the number of the liquid ejection openings, the droplet number distribution table 4. The liquid ejecting apparatus according to claim 1, wherein a droplet number distribution table is provided in which the number of times of droplet ejection is distributed with priority given to liquid ejection ports that are not used in . A linear medium processing system for processing a linear recording medium, comprising the liquid ejection device according to any one of claims 1 to 5.

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