WO2011132694A1

WO2011132694A1 - Printer coordinate generation device, printer coordinate generation method, printer coordinate generation program, three-dimensional ink jet printer, and printing method for three-dimensional ink jet printer

Info

Publication number: WO2011132694A1
Application number: PCT/JP2011/059683
Authority: WO
Inventors: 隆吉村; 義己小野沢; 伸幸小野
Original assignee: 株式会社ミマキエンジニアリング
Priority date: 2010-04-21
Filing date: 2011-04-20
Publication date: 2011-10-27
Also published as: JP5445674B2; JPWO2011132694A1

Abstract

Disclosed is a method for generating printer coordinates intended to realize higher-resolution printed images when printing images on the surface of three-dimensional media. A printer control device (100), which controls the printing of a three-dimensional ink jet printer (200), is provided with a printer coordinate generation unit (104) for identifying print locations at equal intervals on the surface of a medium (300), and also for generating printer coordinates for each print location at the rotation position of the medium (300), which faces the print location tangent horizontal direction; the device is also provided with a printer coordinate compression unit (105) for cancelling the printer coordinates that have the same coordinate difference for at least three consecutive coordinates on all axes and that fall between the start printer coordinate and the end printer coordinate, for setting the compression number that shows the number of cancelled printer coordinates on one of either the start printer coordinate or the end printer coordinate, and for compressing the printer coordinates generated by the printer coordinate generation unit (104).

Description

Print coordinate generation device, print coordinate generation method, print coordinate generation program, three-dimensional inkjet printer, and three-dimensional inkjet printer printing method

The present invention relates to a print coordinate generation apparatus, a print coordinate generation method, and a print coordinate generation program for generating print coordinates of a print position for a three-dimensional ink jet printer that prints an image on the surface of a three-dimensional media. The present invention also relates to a three-dimensional inkjet printer that prints an image on the surface of a three-dimensional shape medium and a printing method for the three-dimensional inkjet printer.

In a two-dimensional ink jet printer that prints an image on a flat medium, ink droplets are ejected at an equal pitch while moving the ink jet head in the scanning direction (also referred to as the Y-axis direction). Is printing. An external device such as a personal computer transfers three pieces of information, that is, a start print coordinate, an end print coordinate, and a discharge pitch at the printing position to the two-dimensional ink jet printer. An image is printed on the surface of the media by specifying the print coordinates of all the print positions that eject ink droplets.

On the other hand, as described in Patent Document 1, a three-dimensional ink jet printer that prints an image on the surface of a three-dimensional shape media can move more axes than a two-dimensional ink jet printer. The five axes of the orthogonal coordinate system of the axis, the Y axis, and the Z axis, and the rotational coordinate system of the A axis and the B axis are movable. In this three-dimensional ink jet printer, ink droplets are ejected from the ink jet head while rotating the medium in the B-axis direction, thereby printing an image on the surface of one scan line of the medium. In the three-dimensional ink jet printer, the ink jet head is arranged in the normal direction of the printing position of the medium in order to stabilize the landing position of the ink droplet.

JP 2007-008110 A

By the way, when printing an image on the surface of a spherical medium with a three-dimensional ink jet printer, the surface shape does not change due to the rotation of the medium. Therefore, the printing position is fixed and the coordinate difference of each axis between the printing positions is always constant. 0. Therefore, as with a two-dimensional ink jet printer, when an external device such as a personal computer transfers three pieces of information such as a start print coordinate, an end print coordinate, and a discharge pitch at a printing position to the three-dimensional ink jet printer, the three-dimensional ink jet printer Then, the print coordinates of each print position can be specified at an appropriate position from these three pieces of information.

However, for example, when printing an image on the surface of an elliptical column-shaped medium, the surface shape changes when the medium is rotated. Therefore, the print position moves in the Y-axis direction or the Z-axis direction, and each position between the print positions is changed. The coordinate difference of the axis fluctuates irregularly. For this reason, even if an external device such as a personal computer transfers three pieces of information such as a start print coordinate, an end print coordinate, and an ejection pitch at a printing position to a three-dimensional ink jet printer, as in the case of a two-dimensional ink jet printer. Inkjet printers have a problem in that the quality of a printed image is lowered because the print coordinates of each print position cannot be specified at an accurate position from these three pieces of information.

Accordingly, the present invention provides a print coordinate generation device, a print coordinate generation method, and a print coordinate generation program that generate print coordinates that can improve the quality of a print image when an image is printed on the surface of a three-dimensional shape medium. The purpose is to provide. Another object of the present invention is to provide a three-dimensional ink jet printer and a printing method for the three-dimensional ink jet printer that can improve the image quality of a printed image when an image is printed on the surface of a three-dimensional shape medium. To do.

The print coordinate generation apparatus according to the present invention uses a three-dimensional ink jet printer to eject an ink droplet from an ink jet head while rotating a three-dimensional shape medium and print an image on the surface of the medium. A print coordinate generation device that generates print coordinates of a print position on a surface, specifies print positions at equal intervals on the surface of the medium, and sets each print position at a rotation position of the medium in which the tangent line of the print position faces the horizontal direction. Coordinate generating means for generating print coordinates is provided.

According to the print coordinate generation device of the present invention, the coordinate generation means specifies the print positions at equal intervals on the surface of the medium, so that the dot intervals of the ink droplets that have landed on the medium are made uniform. The image quality can be improved. In addition, by generating the print coordinates at the rotation position of the medium where the tangent of the print position faces the horizontal direction, the normal line at the print position can be directed in the vertical direction when printing an image on the surface of the medium. Thereby, since the ink jet head and the printing position of the medium can be arranged in parallel, the landing position of the ink droplet can be stabilized.

In this case, the coordinate generation means calculates the moving distance of the media surface when the media is rotated by a minute angle from the predetermined printing position, and sets the position where the total is the predetermined distance as the next printing position. Is preferred. Thus, when specifying the printing position, the moving distance of the media surface when the media is rotated by a minute angle is calculated, and the position where the sum total is a predetermined distance is set as the next printing position, so that the media surface is Can be calculated with high accuracy. For this reason, even if the medium has a complicated shape, the print positions can be specified at equal intervals.

Then, the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and are discarded as either the start print coordinates or the end print coordinates. It is preferable to further include coordinate compression means for setting a compression number indicating the number of printed coordinates. As described above, the print coordinate data is discarded by discarding the print coordinates between the start print coordinates and the end print coordinates among the print coordinates in which the coordinate difference of all the axes is the same continuously for three or more by the coordinate compression unit. The amount can be reduced. As a result, the amount of data transferred to the three-dimensional inkjet printer can be reduced and the data transfer time can be shortened. Moreover, since the coordinate difference of all axes is equal between the start print coordinates and the end print coordinates, a compression number indicating the number of discarded print coordinates is set in either the start print coordinates or the end print coordinates. As a result, the discarded print coordinates can be easily developed in the three-dimensional inkjet printer.

The print coordinate generation method according to the present invention uses a three-dimensional ink jet printer to eject an ink droplet from an ink jet head while rotating a three-dimensional shape medium and print an image on the surface of the medium. A print coordinate generation method for generating a print coordinate of a print position on a surface, wherein the print position is specified at equal intervals on the surface of the medium, and at each rotation position of the medium where the tangent line of the print position faces the horizontal direction, A coordinate generation step for generating print coordinates;

According to the print coordinate generation method according to the present invention, in the coordinate generation step, by specifying the print positions at equal intervals on the surface of the media, the dot intervals of the ink droplets that have landed on the media are made uniform. The image quality can be improved. In addition, by generating the print coordinates at the rotation position of the medium where the tangent of the print position faces the horizontal direction, the normal line at the print position can be directed in the vertical direction when printing an image on the surface of the medium. Thereby, since the ink jet head and the printing position of the medium can be arranged in parallel, the landing position of the ink droplet can be stabilized.

Then, the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and are discarded as either the start print coordinates or the end print coordinates. It is preferable to further include a coordinate compression step for setting a compression number indicating the number of printed coordinates. In this way, in the coordinate compression step, the print coordinate data is discarded by discarding the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more. The amount can be reduced. As a result, the amount of data transferred to the three-dimensional inkjet printer can be reduced and the data transfer time can be shortened. Moreover, since the coordinate difference of all axes is equal between the start print coordinates and the end print coordinates, a compression number indicating the number of discarded print coordinates is set in either the start print coordinates or the end print coordinates. As a result, the discarded print coordinates can be easily developed in the three-dimensional inkjet printer.

The print coordinate generation program according to the present invention uses a three-dimensional ink jet printer to eject ink droplets from an ink jet head while rotating a three-dimensional shape medium to print an image on the surface of the medium. A print coordinate generation program for generating print coordinates of a print position on the front surface, specifying print positions at equal intervals on the surface of the medium, and at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction, A computer generates a coordinate generation step for generating print coordinates.

According to the print coordinate generation program according to the present invention, in the coordinate generation step that causes the computer to function, the dot positions of the ink droplets that have landed on the medium are made uniform by specifying the print positions at equal intervals on the surface of the medium. Therefore, it is possible to improve the quality of the printed image. In addition, by generating the print coordinates at the rotation position of the medium where the tangent of the print position faces the horizontal direction, the normal line at the print position can be directed in the vertical direction when printing an image on the surface of the medium. Thereby, since the ink jet head and the printing position of the medium can be arranged in parallel, the landing position of the ink droplet can be stabilized.

Then, the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and are discarded as either the start print coordinates or the end print coordinates. It is preferable that the computer further functions a coordinate compression step for setting a compression number indicating the number of printed coordinates. In this way, in the coordinate compression step that causes the computer to function, by discarding the print coordinates between the start print coordinates and the end print coordinates among the print coordinates in which the coordinate difference of all axes is the same for three or more consecutive times, Since the data amount of the print coordinates can be reduced, the data transfer amount to the three-dimensional inkjet printer can be reduced and the data transfer time can be shortened. Moreover, since the coordinate difference of all axes is equal between the start print coordinates and the end print coordinates, a compression number indicating the number of discarded print coordinates is set in either the start print coordinates or the end print coordinates. As a result, the discarded print coordinates can be easily developed in the three-dimensional inkjet printer.

In the three-dimensional inkjet printer according to the present invention, image data acquisition means for acquiring image data for printing in which image data to be printed on a medium is associated with each nozzle of the inkjet head, and ink droplets are ejected from the inkjet head. A print coordinate acquisition unit that acquires the print coordinates of each print position at the rotation position of the medium in which the print positions are specified at regular intervals and the tangent line of each print position faces the horizontal direction, and the printing image acquired by the image data acquisition unit Print processing means for printing an image on the surface of the medium by ejecting ink droplets from the inkjet head while rotating the three-dimensional shape medium based on the data and the print coordinates acquired by the print coordinate acquisition means; Have.

According to the three-dimensional inkjet printer according to the present invention, the print coordinates acquired by the print coordinate acquisition unit are acquired by the print coordinate acquisition unit, and the print coordinates acquired by the image data acquisition unit are acquired. By printing an image on the surface of the medium based on the image data, the dot intervals of the ink droplets that have landed on the medium can be made uniform, and the quality of the printed image can be improved. In addition, since the print coordinates are generated at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction, the normal line at the print position is directed vertically when the image is printed on the surface of the medium. be able to. Thereby, since the ink jet head is arranged in the normal line direction at the printing position of the medium, the landing position of the ink droplet can be stabilized.

The print coordinates acquired by the print coordinate acquisition unit are discarded, and the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes are discarded. When a compression number indicating the number of discarded print coordinates is set in either one of the coordinates, the compression number is set between the coordinate value of each axis in the start print coordinates and the coordinate value of each axis in the end print coordinates. It is preferable to further have a developing means for developing the coordinate value equally divided by the number obtained by adding 1 as a discarded print coordinate. In this way, the print coordinates acquired by the print coordinate acquisition unit are discarded, and the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes are discarded, and the start print coordinates and the end When a compression number indicating the number of discarded print coordinates is set in any one of the print coordinates, the expansion means sets the coordinate value of each axis in the start print coordinate and the coordinate value of each axis in the end print coordinate. By expanding a coordinate value obtained by equally dividing the number of compressions by a number obtained by adding 1 to the number of compressions as a discarded print coordinate, the discarded print coordinate can be easily expanded.

In the printing method of the three-dimensional inkjet printer according to the present invention, an image data acquisition step for acquiring image data for printing to be printed on a medium, and a print position at which ink droplets are ejected from the inkjet head are specified at a constant interval, The print coordinate acquisition step that acquires the print coordinates of each print position at the rotation position of the media where the tangent of each print position faces the horizontal direction, and the print coordinates acquired in the print coordinate acquisition step have the same coordinate difference for all axes. When the print coordinates between the start print coordinates and the end print coordinates among the print coordinates are discarded, and either the start print coordinates or the end print coordinates is set to a compression number indicating the number of discarded print coordinates , Discarding the coordinate value obtained by equally dividing the coordinate value of each axis in the start print coordinates and the coordinate value of each axis in the end print coordinates by the number obtained by adding 1 to the compression number A medium having a three-dimensional shape based on a development step for developing the print coordinates, the print image data obtained in the image data acquisition step, the print coordinates obtained in the print coordinate acquisition step, and the print coordinates developed in the development step And a printing step of printing an image on the surface of the medium by ejecting ink droplets from the inkjet head while rotating.

According to the printing method of the three-dimensional inkjet printer according to the present invention, in the printing coordinate acquisition step, the printing coordinates whose printing positions are specified at a constant interval are acquired, and the acquired printing coordinates and the image data acquisition unit acquire the printing coordinates. By printing an image on the surface of the medium based on the print image data, the dot intervals of the ink droplets that have landed on the medium can be made uniform, and the quality of the printed image can be improved. In addition, since the print coordinates are generated at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction, the normal line at the print position is directed vertically when the image is printed on the surface of the medium. be able to. Thereby, since the ink jet head is arranged in the normal line direction at the printing position of the medium, the landing position of the ink droplet can be stabilized. Further, among the print coordinates acquired in the print coordinate acquisition step, the print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes are discarded, and the start print coordinates and the end print If a compression number indicating the number of discarded print coordinates is set in any one of the coordinates, the coordinate value of each axis in the start print coordinates and the coordinate value of each axis in the end print coordinates are set in the expansion step. By expanding the coordinate value obtained by equally dividing the interval by the number obtained by adding 1 to the compression number as the discarded print coordinates, the discarded print coordinates can be easily expanded.

According to the present invention, when printing an image on the surface of a three-dimensional media, it is possible to generate print coordinates that can improve the image quality of the print image. Further, according to the present invention, it is possible to improve the quality of a printed image when an image is printed on the surface of a three-dimensional shape medium.

1 is a block configuration diagram illustrating a printer system according to an embodiment. FIG. It is a figure which shows the moving axis of an inkjet head and a medium. It is a figure which shows the axis | shaft which an inkjet head and a medium move. It is a figure which shows the block configuration of a printer control apparatus. It is a figure showing an example of printing coordinates and image data for printing. 6A to 6C are views showing a cross section of a medium that rotates in the B-axis direction. It is a figure for demonstrating the identification method of a printing position. It is a figure for demonstrating the production | generation method of the specified printing coordinate. It is a figure for demonstrating the production | generation method of the specified printing coordinate. It is the figure which showed the relationship of the printing coordinate in three continuous printing positions. It is a figure for demonstrating the compression method of a printing coordinate. It is the figure which showed the relationship of the printing coordinate in three continuous printing positions. It is a figure which shows the block configuration of the printing control part in a three-dimensional inkjet printer. It is a flowchart which shows the printing ground production | generation processing method by a printing coordinate production | generation part. It is a flowchart which shows the printing coordinate compression processing method by a printing coordinate compression part. It is a figure for demonstrating a printing coordinate compression process. It is a flowchart which shows the printing coordinate expansion | deployment process by a printing coordinate expansion | deployment part.

Hereinafter, preferred embodiments of a print coordinate generation device, a print coordinate generation method, a print coordinate generation program, a three-dimensional inkjet printer, and a printing method of a three-dimensional inkjet printer according to the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

FIG. 1 is a diagram showing a configuration of a three-dimensional ink jet printer and a printer control device according to the present embodiment. As shown in FIG. 1, for example, a personal computer (PC) is used as the printer control apparatus 100, and the printer control apparatus 100 and the three-dimensional inkjet printer 200 are electrically connected by a wiring cable. The printer control apparatus 100 and the three-dimensional inkjet printer 200 perform bidirectional communication using commands and status.

The basic communication procedure between the printer control device 100 and the three-dimensional inkjet printer 200 will be specifically described.

First, the printer control device 100 transmits a command for acquiring the status of the three-dimensional inkjet printer 200 to the three-dimensional inkjet printer 200. When the three-dimensional ink jet printer 200 receives a command from the printer control device 100, the three-dimensional ink jet printer 200 returns a current status, for example, a status indicating whether printing is possible, to the printer control device 100.

The printer control device 100 checks the status from the three-dimensional ink jet printer 200 and, if printing is possible, sequentially transmits print coordinates and image data for printing to the three-dimensional ink jet printer 200 for printing an image. To do. The three-dimensional ink jet printer 200 sequentially stores these print coordinates and print image data in a memory.

Thereafter, when the printer control device 100 transmits a command for executing printing, the three-dimensional inkjet printer 200 receives this command and executes printing based on the print coordinates and the print image data.

FIG. 2 is a conceptual diagram showing the configuration of the main part of the three-dimensional inkjet printer. FIG. 3 is a diagram illustrating the moving axes of the inkjet head and the medium. As shown in FIGS. 2 and 3, the three-dimensional ink jet printer 200 is a printer for printing an image on the surface of a medium 300 having a three-dimensional shape (ellipsoidal column shape). In the present embodiment, description will be made using an elliptical columnar medium 300 as an example of a three-dimensional medium. The three-dimensional inkjet printer 200 controls an inkjet head 210 that ejects ink droplets onto the surface of the medium 300, a support unit 220 that supports the medium 300 and the inkjet head 210, and the inkjet head 210 and the support unit 220. A printing control unit 230.

The support unit 220 includes an X-axis direction moving unit 221 that moves the medium 300 in the X-axis direction that is the horizontal direction, a Z-axis direction moving unit 223 that moves the medium 300 in the Z-axis direction that is the vertical direction, and the medium 300. A B-axis rotating unit 224 that rotates to rotate about the X-axis (B-axis), an A-axis rotating unit 225 that rotates the medium 300 to revolve about the Y-axis (A-axis), and the inkjet head 210. And a Y-axis direction moving unit 222 that moves the Y-axis in the Y-axis direction that is the horizontal direction. For this reason, in the three-dimensional ink jet printer 200, the medium 300 and the ink jet head 210 are supported by the support unit 220, which is an orthogonal coordinate system of the X axis, the Y axis, and the Z axis, and a rotational coordinate system of the A axis and the B axis. The shaft can be moved (rotated).

The print control unit 230 performs print control based on print coordinates received from the printer control apparatus 100. The print control unit 230 transmits the control signal Sc to the ink jet head 210 and the support unit 220, thereby controlling the drive of the support unit 220 and controlling the ejection of the ink jet head 210. The print control unit 230 controls the X-axis direction moving unit 221 and the A-axis rotation unit 225 to adjust the position of the medium 300 in the X-axis direction and the A-axis direction, thereby specifying the print band and the print band. Switch. Then, the print control unit 230 controls the Y-axis direction moving unit 222 and adjusts the position of the inkjet head 210 in the Y-axis direction while controlling the B-axis rotation unit 224 to rotate the medium 300 in the B-axis direction. At the same time, by controlling the Z-axis direction moving unit 223 to adjust the position of the medium 300 in the Z-axis direction, and ejecting ink droplets from the inkjet head 210, an image is printed on the print band on the surface of the medium 300. Print.

The print control unit 230 also functions as a developing unit according to the embodiment of the present invention, details of which will be described later.

FIG. 4 is a diagram showing a block configuration of the printer control apparatus. As shown in FIG. 4, the printer control apparatus 100 includes a shape data input unit 101, an image data input unit 102, a print image data generation unit 103, a print coordinate generation unit 104, a print coordinate compression unit 105, A data output unit 106.

The shape data input unit 101 is for inputting shape data for specifying the shape of the medium 300 to be printed. The shape data of the medium 300 in this embodiment can be defined by, for example, a relational expression in which the length of the medium 300 in the axial direction and the lengths of the major axis and the minor axis of the ellipse are defined.

The image data input unit 102 is for inputting image data to be printed on the medium 300.

The printing image data generation unit 103 generates printing image data based on the shape data input from the shape data input unit 101 and the image data input from the image data input unit 102. The print image data generation unit 103 associates the image data input from the image data input unit 102 with each nozzle of the inkjet head 210 provided in the three-dimensional inkjet printer 200 at intervals specified by the resolution.

The print coordinate generation unit 104 generates print coordinates for printing an image on the surface of the medium 300 based on the shape data input from the shape data input unit 101. The print coordinate generation unit 104 specifies the print positions at equal intervals on the surface of the medium 300, and generates the print coordinates of each print position at the rotation position of the medium 300 where the tangent line of each print position faces the horizontal direction. The print coordinates generated by the print coordinate generation unit 104 include a coordinate value of each axis indicating a print position on the surface of the medium 300 and a compression number set by the print coordinate compression unit 105 described later. Therefore, the print coordinates are the X-axis coordinate value (X-axis coordinate), the Y-axis coordinate value (Y-axis coordinate), the Z-axis coordinate value (Z-axis coordinate), and the A-axis coordinate value (A-axis coordinate). , B-axis coordinate value (B-axis coordinate) and compression number n are included, and are represented by P (X, Y, Z, A, B, n). The print coordinates are also added with a head number corresponding to an ink color (for example, black, cyan, magenta, yellow), a UV curing parameter, and the like. Is omitted.

FIG. 5 is a diagram showing an example of printing coordinates and printing image data. As shown in FIG. 5, a plurality of print coordinates and print image data are generated in a one-to-one correspondence with each print cell C of each print band in the medium 300. Note that the width of the print band and the size of the print cell C are determined by the size of the inkjet head 210, that is, the number and interval of the nozzles. Then, the position of any nozzle of the inkjet head 210 is expressed as printing coordinates. For example, in the print coordinates, the position of the lower end nozzle in the inkjet head 210 is represented as a reference point of the inkjet head 210. Since the three-dimensional inkjet printer 200 performs printing while rotating the medium 300 in the B-axis direction, the direction in which the medium 300 and the inkjet head 210 relatively move (left side in FIG. 5) is the scan direction.

By the way, in the three-dimensional ink jet printer 200, in order to stabilize the landing position of the ink droplet, the ink jet head 210 is arranged in the normal direction of the print position when the tangent line of the print position on the medium 300 is directed in the horizontal direction. Ink droplets are ejected. Further, as described above, the three-dimensional inkjet printer 200 performs printing while rotating the medium 300 in the B-axis direction. For this reason, the print coordinates of each print position vary as the medium 300 rotates in the B-axis direction.

6A to 6C are diagrams showing a cross section of the medium 300 that rotates in the B-axis direction, and shows the change in the printing position when the elliptical columnar medium is rotated in the B-axis direction. As shown in FIGS. 6A to 6C, when the elliptical columnar medium 300 is rotated in the B-axis direction, its surface shape changes. For this reason, the printing position varies in the Y-axis direction and the Z-axis direction depending on the rotational position of the medium 300 in the B-axis direction. In addition, since the variation in the print position in the Y-axis direction and the Z-axis direction is not linear, the coordinate difference between the Y-axis and the Z-axis between the print positions varies. Furthermore, since the radius in the B-axis direction of the medium 300 is not uniform, if the print positions are specified at equal intervals on the surface of the medium 300, the rotation angle in the B-axis direction (coordinate difference between the B axes) and the distance between the print positions Does not necessarily match.

Therefore, the printing position at the rotational position in FIG. 6A is P1 (Y1, Z1, B1), the printing position at the rotational position in FIG. 6B is P2 (Y2, Z2, B2), and the printing position at the rotational position in FIG. Assuming P3 (Y3, Z3, B3), the printing positions are P1 ≠ P2 ≠ P3, and the coordinate values of the printing positions are | Y2-Y1 | ≠ | Y3-Y2 |, | Z2-Z1 | ≠ | Z3- Z2 |, | B2-B1 | ≠ | B3-B2 |. Therefore, the print coordinate generation unit 104 specifies all print positions, and generates print coordinates for all the specified print positions. Note that since the X axis and the A axis are fixed within one scan in which printing of one print band is performed, the coordinate values of the X axis and the A axis at each printing position are constant.

FIG. 7 is a diagram for explaining a method for specifying a printing position. As shown in FIG. 7, when specifying the print position, the print coordinate generation unit 104 first calculates the movement distance ΔL of the media surface when the medium 300 is rotated by a minute angle ΔB from the nth print position. To do. Then, the print coordinate generation unit 104 adds the movement distance ΔL, and specifies the position where the sum is the predetermined distance L as the (n + 1) th print position.

8 and 9 are diagrams for explaining a method for generating the specified print coordinates. When generating the print coordinates of the nth print position Pn, first, as shown in FIG. 8, the coordinates (Yn ₁ , Zn ₁ ) of the print position Pn are obtained based on the rotation angle Bn of the medium 300. Then, as shown in FIG. 9, the inclination θn of the tangent line at the printing position Pn is obtained, and the coordinates of the printing position Pn ( Yn ₂ , Zn ₂ ) is obtained. The obtained coordinates (Yn ₂ , Zn ₂ ) are set as printing coordinates (Yn, Zn) of the printing position Pn.

The print coordinate compression unit 105 compresses the print coordinates generated by the print coordinate generation unit 104. The print coordinate compression unit 105 sets the print coordinates in which three or more consecutive coordinate differences are the same among the print coordinates generated by the print coordinate generation unit 104 as compression targets. Then, the print coordinate compression unit 105 discards the print coordinates between the start print coordinates and the end print coordinates among the print coordinates to be compressed. Further, the print coordinate compression unit 105 counts the number of discarded print coordinates as a compression number, and sets this count value as the end print coordinate.

Here, a printing coordinate compression method by the printing coordinate compression unit 105 will be described with reference to FIGS. FIG. 10 is a diagram showing the relationship of printing coordinates at three consecutive printing positions. FIG. 11 is a diagram for explaining a printing coordinate compression method.

Consider three consecutive printing positions P1 to P3 as shown in FIG. The print coordinates generated by the print coordinate generation unit 104 are each represented by (X, Y, Z, A, B, 0), and all the compression numbers are set to 0.

Here, the coordinate difference between the X-axis coordinates of P1 and P2 is 1x1, the coordinate difference between the Y-axis coordinates of P1 and P2 is ly1, the coordinate difference between the P1 and P2 Z-axis coordinates is lz1, and A1 of P1 and P2 The coordinate difference in the axis coordinate is la1, and the coordinate difference in the B-axis coordinate between P1 and P2 is lb1. Also, the coordinate difference between the X-axis coordinates of P3 and P2 is lx2, the coordinate difference between the Y-axis coordinates of P3 and P2 is ly2, the coordinate difference between the Z-axis coordinates of P3 and P2 is lz2, and the A-axis of P3 and P2 A coordinate difference in coordinates is la2, and a coordinate difference in the B-axis coordinates of P3 and P2 is lb2. When all of lx1 = lx2, ly1 = ly2, lz1 = lz2, la1 = la2, and lb1 = lb2 are satisfied, it is determined that the print coordinate differences at the print positions P1 to P3 are equal on all axes.

When the coordinate differences of all axes at the printing positions P1 to P3 are equal, as shown in FIG. 11, the printing positions P1 to P3 are set as the printing positions to be compressed, and the start printing coordinates (P1) and the ending printing coordinates in the compression objects are set. The print coordinates (P2) between (P3) are discarded. Since there is only one discarded print coordinate, 1 is set as the compression number in the end print coordinate (P3). Thereby, the end print coordinates of P3 are (X, Y, Z, A, B, 1), and 1 is set as the compression number. Note that the starting print coordinates of P1 remain (X, Y, Z, A, B, 0).

The data output unit 106 generates a print image data generated by the print image data generation unit 103 and a print coordinate generated by the print coordinate generation unit 104 and compressed by the print coordinate compression unit 105. The printing control of the three-dimensional inkjet printer 200 is performed. As described above, the data output unit 106 transmits a command to the three-dimensional inkjet printer 200 and confirms the status of the three-dimensional inkjet printer 200. When the status of the three-dimensional inkjet printer 200 indicates that printing is possible, the data output unit 106 prints the print image data generated by the print image data generation unit 103 and the print coordinate generation unit 104. The print coordinates compressed by the coordinate compression unit 105 are sequentially output to the three-dimensional inkjet printer 200. Thereafter, when the data output unit 106 transmits a print execution command, the three-dimensional ink jet printer 200 prints an image on the surface of the medium 300.

FIG. 12 is a block diagram showing a print control unit in the three-dimensional inkjet printer. As illustrated in FIG. 12, the print control unit 230 of the three-dimensional inkjet printer 200 includes an image data input unit 201, a print coordinate input unit 202, a print coordinate development unit 203, and a print processing unit 204.

The image data input unit 201 acquires print image data output from the data output unit 106 of the printer control apparatus 100 and inputs the print image data to the print processing unit 204.

The print coordinate input unit 202 acquires the print coordinates output from the data output unit 106 of the printer control apparatus 100 and inputs the print coordinates to the print coordinate development unit 203.

The print coordinate developing unit 203 develops the compressed print coordinates when the print coordinates input by the print coordinate input unit 202 are compressed. That is, the print coordinate developing unit 203 determines that the print coordinates input by the print coordinate input unit 202 are between the start print coordinates and the end print coordinates among the print coordinates to be compressed in the print coordinate compression unit 105 of the printer control apparatus 100. When the print coordinates are discarded and the compression number is set for the end print coordinates, the compression number is incremented by 1 between the coordinate value of each axis in the start print coordinates and the coordinate value of each axis in the end print coordinates. The coordinate value equally divided by the number is expanded as the discarded print coordinate.

More specifically, when the print coordinate input unit 202 sets a print number of 1 or more to the print coordinate input unit 202, the print coordinate is the end print coordinate in the compression target. It is determined that the previous print coordinate is the start print coordinate in the compression target. Then, the print coordinate developing unit 203 obtains a coordinate difference between each axis between the start print coordinate and the end print coordinate, and obtains a coordinate difference obtained by equally dividing the coordinate difference between each axis by the number obtained by adding 1 to the compression number. Then, the coordinate value corresponding to the obtained coordinate difference of each axis is developed (restored) as the print coordinates discarded by the compression.

The print processing unit 204 is based on the print image data input by the image data input unit 201 and the print coordinates input by the print coordinate input unit 202 and developed by the print coordinate development unit 203. This print processing is performed. That is, the print processing unit 204 prints an image on the surface of the medium 300 by moving the support unit 220 based on the print coordinates and ejecting ink droplets from the inkjet head 210 based on the print image data. .

Next, the processing operation of the printer control apparatus 100 will be described with reference to FIGS. FIG. 13 is a flowchart showing print coordinate generation processing by the print coordinate generation unit. FIG. 14 is a flowchart showing print coordinate compression processing by the print coordinate compression unit.

Here, the printer control apparatus 100 is mainly configured by a computer including a CPU, a ROM, and a RAM, for example, and the functions of the print coordinate generation unit 104 and the print coordinate compression unit 105 are printed coordinates on the ROM and RAM. This is realized by reading the generation program and the print coordinate compression program and executing the print coordinate generation program and the print coordinate compression program by the CPU. That is, the operation of the printer control apparatus 100 is comprehensively controlled by the CPU, the print coordinate generation program and the print coordinate compression program are executed, and the print coordinate generation process shown in the flowchart of FIG. 13 and the flowchart of FIG. Printing coordinate compression processing and the like are performed. In this case, the CPU functions as each unit of the printer control apparatus 100.

Here, the print coordinate generation program and the print coordinate compression program may be provided by being stored in a recording medium such as FD, CD-ROM, DVD, or ROM, or a semiconductor memory, respectively. It may be provided via a network as a computer data signal superimposed on a carrier wave. In this case, each of the printer control devices 100 is a reading device (not shown) for reading data such as a program from the recording medium, and a communication device (not shown) for acquiring data such as a program via a network. ).

Note that the print coordinate generation unit 104 and the print coordinate compression unit 105 may be an ASIC, FPGA, or the like mounted on the printer control apparatus 100. Further, the print coordinate generation unit 104 and the print coordinate compression unit 105 may include a CPU that controls the entire printer control apparatus 100, an ASIC, an FPGA, and the like.

First, the printer control device 100 acquires the shape data of the medium 300 input from the shape data input unit 101 and also acquires the image data input from the image data input unit 102.

The printing image data generation unit 103 generates printing image data based on the acquired shape data and image data.

On the other hand, the print coordinate generation unit 104 performs print coordinate generation processing based on the acquired shape data, and print coordinates for printing the print image data generated by the print image data generation unit 103 on the surface of the medium 300. Is generated.

Here, the print coordinate generation processing by the print coordinate generation unit 104 will be described in detail with reference to FIG.

As shown in FIG. 13, the print coordinate generation unit 104 first sets a number n indicating the order of print positions to 1 and sets a reference rotation angle B1 of the print position P1 as an initial setting (step S1). .

Next, the print coordinate generation unit 104 obtains the coordinates (Yn ₁ , Zn ₁ ) of the print position Pn based on the rotation angle Bn of the medium 300 (step S2). Here, when step S2 is performed for the _{first time} , the coordinates (Yn ₁ , Zn ₁ ) of the printing position Pn are obtained based on the reference rotation angle B1 set in step S1, and when step S2 is performed once, it will be described later. The coordinates (Yn ₁ , Zn ₁ ) of the printing position Pn are obtained based on the rotation angle Bn set in step S6. In the present embodiment, the X-axis coordinates and the A-axis coordinates are not required in step S2 because the X-axis coordinates and the A-axis coordinates are fixed except when the print band to be printed is switched. For this reason, in this process, the explicit description of the X-axis coordinates and the A-axis coordinates is omitted. However, obtaining the X-axis coordinates and the A-axis coordinates in step S2 and subsequent steps is not excluded.

Next, the print coordinate generation unit 104 obtains an angle θn of the tangent line from the tangent expression at the print position Pn (step S3). The angle θn of the tangent line can be obtained by, for example, θn = f ′ (Bn).

Next, the print coordinate generation unit 104 rotates the coordinates (Yn ₁ , Zn ₁ ) obtained in step S2 by an angle θn so that the tangent at the print position Pn is horizontal, and the coordinates (Yn ₂ ) rotated by this angle θn. , Zn ₂ ) is specified as the printing coordinates of the printing position Pn (step S4). For this reason, the printing coordinates of the printing position Pn are (Yn ₂ , Zn ₂ , θn).

Next, the print coordinate generation unit 104 adds one number n indicating the order of the print positions (step S5).

Next, the print coordinate generation unit 104 specifies the next print position Pn, and obtains the rotation angle Bn of the medium 300 from the previous print position P (n−1) to the next print position Pn (step) S6). That is, the print coordinate generation unit 104 adds the moving distance ΔL of the surface of the medium 300 when the medium 300 is rotated by a minute angle ΔB from the current rotation angle B (n−1). Then, the print coordinate generation unit 104 specifies the position of the surface of the medium 300 where the total of the movement distance ΔL is the predetermined distance L as the next print position Pn, and the total of the minute angle ΔB at this time is defined as the rotation angle Bn. To do.

Next, the print coordinate generation unit 104 determines whether or not the print position Pn is the end point (step S7). If the print coordinate generation unit 104 determines that the print position Pn is not the end point (step S7: NO), the print coordinate generation unit 104 returns to step S2 and repeats steps S2 to S6 again. On the other hand, if the print coordinate generation unit 104 determines that the print position Pn is the end point (step S7: YES), the print coordinate generation process ends.

In this way, when the print coordinates are generated by the print coordinate generation unit 104, the print coordinate compression unit 105 performs a print coordinate compression process on the generated print coordinates.

Here, the print coordinate compression processing by the print coordinate compression unit 105 will be described in detail with reference to FIG.

As shown in FIG. 14, the print coordinate compression unit 105 first determines the print coordinates of the first print position P1 with the print coordinates (Y1, Z1, B1) specified in step S4 described above (step S11). .

Next, the print coordinate compression unit 105 sets the number n indicating the order of the print positions to 2, and clears the count value of the compression number (step S12).

Next, the print coordinate compression unit 105 determines whether there is data of the nth print position Pn (step S13). If it is determined that there is no data at the print position Pn (step S13: NO), the print coordinate compression unit 105 ends the print coordinate compression process.

On the other hand, if it is determined that there is data at the print position Pn (step S13: YES), the print coordinate compression unit 105 determines each of the (n-1) th print position P (n-1) and the nth print position Pn. A coordinate difference between the axes is obtained, and the obtained coordinate difference between the axes is set as a reference coordinate difference (step S14). The print position P (n−1) indicates the previous print position, and the print position Pn indicates the current print position.

Next, the print coordinate compression unit 105 determines whether or not there is data of the (n + 1) th print position P (n + 1) (step S15). If it is determined that there is data of the print position P (n + 1) (step S15: YES), the print coordinate compression unit 105 determines each axis of the nth print position Pn and the (n + 1) th print position P (n + 1). Is obtained, and the obtained coordinate difference of each axis is set as a compression target coordinate difference (step S16).

Next, the print coordinate compression unit 105 compares the coordinate difference of each axis between the reference coordinate difference obtained in step S14 and the compression target coordinate difference obtained in step S16, and determines whether the coordinate difference is equal in all axes. Is determined (step S17).

If it is determined that the coordinate difference is the same for all axes (step S17: YES), the print coordinate compression unit 105 discards the print coordinate at the print position Pn (step S18). Then, the print coordinates discarded by incrementing the compression number (+1) are counted, and the number n indicating the order of the print positions is incremented (+1) (step S19). Then, it returns to step S15 and repeats the process mentioned above again.

On the other hand, if it is determined that the coordinate difference is different on at least one axis (step S17: NO), the print coordinate compression unit 105 determines the print coordinate of the print position Pn and sets the count value of the compression number to the print coordinate. (Step S20). Note that, as described above, the compression number set for the print coordinates indicates the number of print coordinates discarded in step S18. Then, the count value of the compression number is cleared, and the number n indicating the order of the printing positions is incremented (+1) (step S21). Then, it returns to step S14 and repeats the process mentioned above again.

If it is determined in step S15 described above that there is no data at the print position P (n + 1) (step S15: NO), the print coordinate compression unit 105 determines that the print position Pn is the last data, and the print position Pn. Is determined, and the count value of the compression number is set as the print coordinate (step S22). Then, the print coordinate compression process ends.

Here, the print coordinate compression processing will be described in detail with reference to FIG. FIG. 15 is a diagram for explaining the print coordinate compression processing.

15, P1 to P8 indicate printing positions, and P1 to P3, P3 to P5, and P5 to P8 have the same coordinate difference for all axes.

First, when the first print position P1 is input to the print coordinate compression unit 105, the input print coordinates (X, Y, Z, A, B, 0) are fixed as they are. The number n indicating the order of the printing positions is set to 2, and the count value of the compression number is cleared to 0.

Next, when the second print position P2 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the first print position P1 and the second print position P2 is specified as the reference coordinate difference, A coordinate difference between the axes of the second printing position P2 and the third printing position P3 is specified as a compression target coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are the same for all axes, the print coordinate at the print position P2 is discarded. Then, the compression number is incremented to 1, and the number n indicating the order of the printing positions is incremented to 3.

Next, when the third print position P3 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the third print position P3 and the fourth print position P4 is specified as the compression target coordinate difference. Since the reference coordinate difference and the compression target coordinate difference are the same for all axes in the previous processing, the reference coordinate difference is the already specified reference coordinate difference (the coordinate difference between each axis of the print position P2 and the print position P1). ) Is not used to newly specify the reference coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are different in at least one of the axes, the printing coordinate of the printing position P3 is determined, and 1 is set as the compression number in the determined printing coordinate of the printing position P3. . Then, the count value of the compression number is cleared to 0, and the number n indicating the order of the printing positions is incremented to 4.

Next, when the fourth print position P4 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the third print position P3 and the fourth print position P4 is specified as the reference coordinate difference, A coordinate difference between the axes of the fifth printing position P5 and the fourth printing position P4 is specified as a compression target coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are the same for all axes, the print coordinate at the print position P4 is discarded. Then, the compression number is incremented to 1 and a number n indicating the order of the printing positions is incremented to 5.

Next, when the fifth print position P5 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the fifth print position P5 and the sixth print position P6 is specified as the compression target coordinate difference. Since the reference coordinate difference and the compression target coordinate difference are the same for all axes in the previous process, the reference coordinate difference is the already specified reference coordinate difference (the coordinate difference between each axis of the print position P4 and the print position P3). ) Is not used to newly specify the reference coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are different in at least one of the axes, the print coordinate of the print position P5 is determined, and 1 is set as the compression number in the determined print coordinate of the print position P5. . Then, the count value of the compression number is cleared to 0, and the number n indicating the order of the printing positions is incremented to 6.

Next, when the sixth print position P6 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the fifth print position P5 and the sixth print position P6 is specified as the reference coordinate difference, A coordinate difference between the respective axes of the sixth printing position P6 and the seventh printing position P7 is specified as a compression target coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are the same for all axes, the print coordinate at the print position P6 is discarded. Then, the compression number is incremented to 1, and the number n indicating the order of the printing positions is incremented to 7.

Next, when the seventh print position P7 is input to the print coordinate compression unit 105, the coordinate difference between the axes of the seventh print position P7 and the eighth print position P8 is specified as the compression target coordinate difference. Since the reference coordinate difference and the compression target coordinate difference are the same for all axes in the previous process, the reference coordinate difference is the already specified reference coordinate difference (the coordinate difference between each axis of the printing position P6 and the printing position P5). ) Is not used to newly specify the reference coordinate difference. In this case, since the reference coordinate difference and the compression target coordinate difference are the same for all axes, the print coordinate at the print position P7 is discarded. Then, the number of compression is incremented to 2, and the number n indicating the order of the printing positions is incremented to 8.

Next, when the eighth print position P8 is input to the print coordinate compression unit 105, there is no ninth print position P9 and the print position P7 is the end point, so the print coordinates of the print position P8 are determined. 2 is set as the compression number in the printing coordinates of the determined printing position P8.

As described above, when the print coordinates are compressed by the print coordinate compression unit 105, the data output unit 106 generates the print image data generated by the print image data generation unit 103 and the print coordinate generation unit 104. At the same time, the print image compressed by the print coordinate compression unit 105 is transmitted to the print control unit 230 of the three-dimensional inkjet printer 200.

Next, the processing operation of the print control unit 230 in the three-dimensional inkjet printer 200 will be described with reference to FIG. FIG. 16 is a flowchart showing the print coordinate development process by the print coordinate development unit.

Here, the print control unit 230 is configured mainly by a computer including a CPU, a ROM, and a RAM, for example, and the function of the print coordinate development unit 203 reads a print coordinate development processing program on the ROM or RAM, This print coordinate development program is executed by the CPU. That is, the operation of the print control unit 230 is comprehensively controlled by the CPU, the print coordinate development processing program is executed, and the print coordinate development processing shown in the flowchart of FIG. 16 is performed. In this case, the CPU functions as each unit of the print control unit 230.

Here, the print coordinate development program may be provided by being stored in a recording medium such as an FD, a CD-ROM, a DVD, or a ROM, or a semiconductor memory, or superimposed on a carrier wave. It may be provided via a network as a computer data signal. In this case, each of the print control units 230 is a reading device (not shown) for reading data such as a program from the recording medium, and a communication device (not shown) for acquiring data such as a program via a network. ).

Note that the print coordinate developing unit 203 may be an ASIC or FPGA mounted on the three-dimensional inkjet printer 200. Further, the print coordinate developing unit 203 may include a CPU that controls the entire three-dimensional inkjet printer 200, an ASIC, an FPGA, and the like.

First, the print control unit 230 of the three-dimensional ink jet printer 200 acquires the print image data transmitted from the printer control device 100 by the image data input unit 201, and uses the print coordinates transmitted from the printer control device 100 as the print coordinates. Obtained by the input unit 202.

The print coordinate development unit 203 performs a print coordinate development process for the print coordinates acquired by the print coordinate input unit 202.

Here, with reference to FIG. 16, the print coordinate development processing by the print coordinate development unit 203 will be described in detail.

The print coordinate developing unit 203 first determines whether or not a compression number of 1 or more is set for the print coordinates (step S31). If it is determined that a compression number of 1 or more is not set for the print coordinates (step S31: NO), the print coordinate development unit 203 determines that the print coordinates are not compressed, and proceeds to step S35. Print coordinates are output to the print processing unit 204.

On the other hand, if it is determined that a compression number of 1 or more is set for the print coordinates (step S31: YES), the print coordinate development unit 203 acquires the coordinate value of each axis at the print position output immediately before ( Step S32).

Next, the print coordinate development unit 203 calculates the interval between the compressed print coordinates based on the coordinate difference between the axes of the current print position and the previous print position and the compression number set in the current print coordinates. Is calculated (step S33).

Next, the print coordinate development unit 203 develops (restores) the discarded print coordinates by the number of compressions based on the coordinate difference between the print coordinates calculated in step S33 (step S34).

Next, the print coordinate developing unit 203 outputs the print coordinates developed in step S34 to the print processing unit 204 (step S35).

Next, the print coordinate developing unit 203 determines whether or not all data has been completed (step S36). If it is determined that all data has not been completed yet (step S36: NO), the print coordinate developing unit 203 returns to step S31 and repeats the above-described processing again. On the other hand, if it is determined that all data has been completed (step S36: YES), the print coordinate developing unit 203 ends the print coordinate developing process.

As described above, when the print coordinates compressed by the print coordinate development unit 203 are developed, the print processing unit 204 supports based on the print coordinates developed by the print coordinate development unit 203 acquired by the print coordinate input unit 202. An image is printed on the surface of the medium 300 by moving the unit 220 and ejecting ink droplets from the inkjet head 210 based on the print image data input by the image data input unit 201.

As described above, according to the printer control apparatus 100 according to the present embodiment, the print coordinate generation unit 104 specifies the print positions on the surface of the medium 300 at equal intervals, thereby causing ink droplets that have landed on the medium 300. Since the dot intervals are made uniform, it is possible to improve the quality of the printed image. In addition, by generating the print coordinates at the rotation position of the medium 300 where the tangent of the print position faces the horizontal direction, the normal line at the print position can be directed in the vertical direction when printing an image on the surface of the medium 300. . Thereby, since the inkjet head 210 and the printing position of the medium 300 can be arranged in parallel, the landing position of the ink droplet can be stabilized.

Further, according to the present embodiment, when the print position is specified by the print coordinate generation unit 104, the movement distance ΔL of the surface of the medium 300 when the medium 300 is rotated by a minute angle ΔB is calculated, and the sum is predetermined. By setting the position corresponding to the distance L as the next printing position, the distance on the surface of the medium 300 can be calculated with high accuracy. For this reason, even if the medium 300 has a complicated shape, the printing positions can be specified at equal intervals.

Furthermore, according to the present embodiment, the print coordinate compression unit 105 discards the print coordinates between the start print coordinates and the end print coordinates among the print coordinates in which the coordinate difference of all axes is the same for three or more consecutive times. As a result, the data amount of the print coordinates can be reduced. As a result, the amount of data transferred to the three-dimensional inkjet printer 200 can be reduced and the data transfer time can be shortened. Moreover, since the coordinate difference of all axes is equal between the start print coordinates and the end print coordinates, the three-dimensional ink jet printer 200 is set by setting a compression number indicating the number of discarded print coordinates as the end print coordinates. In, the discarded print coordinates can be easily developed.

In this case, by setting the number of compressions to the end print coordinates, the print coordinates can be compressed and expanded in time series, so that the processing speed can be increased.

Further, according to the three-dimensional inkjet printer 200 according to the present embodiment, the print coordinate input unit 202 acquires the print coordinates whose print positions are specified at regular intervals. By printing an image on the surface of the medium 300 based on the print image data acquired in 201, the dot intervals of the ink droplets that have landed on the medium 300 can be made uniform, and the quality of the printed image can be improved. Can be planned. In addition, since the print coordinates are generated at the rotation position of the medium 300 in which the tangent of the print position faces the horizontal direction, the normal line at the print position is set to the vertical direction when the image is printed on the surface of the medium 300. Can be directed to. Thereby, since the inkjet head 210 is disposed in the normal direction at the printing position of the medium 300, the landing position of the ink droplet can be stabilized.

Furthermore, the print coordinates acquired by the print coordinate input unit 202 are discarded, and the print coordinates between the start print coordinates and the end print coordinates among the print coordinates where the coordinate differences of all axes are the same are discarded. When a compression number indicating the number of discarded print coordinates is set in any one of the coordinates, the coordinate value of each axis at the start print coordinates and the coordinate of each axis at the end print coordinates are set by the print coordinate development unit 203. It is discarded by expanding the coordinate difference (or coordinate value) equally divided by the number obtained by adding 1 to the compression number between the values as the coordinate difference (or print coordinates) between the discarded print coordinates. It is possible to easily develop the print coordinates.

The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the present embodiment is not limited to an elliptical columnar medium, but can be applied to printing of various three-dimensional media. For example, even in the case of a medium such as a spherical shape, a gourd shape, a triangular prism shape, a quadrangular prism shape, or a cylindrical shape, the image quality of a printed image can be improved by applying the idea of the present invention.

Claims

In order to cause ink droplets to be ejected from an inkjet head while rotating a three-dimensional shape medium by a three-dimensional ink jet printer to print an image on the surface of the medium, print coordinates of a print position on the surface of the medium are set. A print coordinate generation device for generating,
Coordinate generating means for specifying the print positions at equal intervals on the surface of the medium and generating print coordinates of the respective print positions at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction.
Print coordinate generator.
The coordinate generation means includes
From the predetermined printing position, the moving distance of the surface of the medium when the medium is rotated by a minute angle is calculated, and the position where the sum is a predetermined distance is set as the next printing position.
The print coordinate generation apparatus according to claim 1.
The print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and discarded to either the start print coordinates or the end print coordinates Further comprising coordinate compression means for setting a compression number indicating the number of the printed coordinates.
The print coordinate generating apparatus according to claim 1 or 2.
In order to cause ink droplets to be ejected from an inkjet head while rotating a three-dimensional shape medium by a three-dimensional ink jet printer to print an image on the surface of the medium, print coordinates of a print position on the surface of the medium are set. A print coordinate generation method for generating,
A coordinate generation step of specifying the print positions at equal intervals on the surface of the medium and generating print coordinates of the print positions at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction;
Print coordinate generation method.
The print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and discarded to either the start print coordinates or the end print coordinates A coordinate compression step of setting a compression number indicating the number of the printed coordinates.
The printing coordinate generation method according to claim 4.
In order to cause ink droplets to be ejected from an inkjet head while rotating a three-dimensional shape medium by a three-dimensional ink jet printer to print an image on the surface of the medium, print coordinates of a print position on the surface of the medium are set. A print coordinate generation program to be generated,
A coordinate generation step of specifying the print positions at equal intervals on the surface of the medium and generating a print coordinate of each print position at the rotation position of the medium in which the tangent line of the print position faces the horizontal direction functions as a computer Let
Print coordinate generation program.
The print coordinates between the start print coordinates and the end print coordinates among the print coordinates having the same coordinate difference of all axes for three or more are discarded, and discarded to either the start print coordinates or the end print coordinates Further causing the computer to function a coordinate compression step of setting a compression number indicating the number of the printed coordinates.
The print coordinate generation program according to claim 6.
Image data acquisition means for acquiring image data for printing in which image data to be printed on a medium is associated with each nozzle of the inkjet head;
Print coordinate acquisition for acquiring the print coordinates of each print position at the rotation position of the medium in which the print positions at which ink droplets are ejected from the inkjet head are specified at regular intervals and the tangent line of each print position faces the horizontal direction Means,
Based on the image data for printing acquired by the image data acquisition unit and the printing coordinates acquired by the printing coordinate acquisition unit, ink droplets are ejected from an inkjet head while rotating a three-dimensional media. Print processing means for printing an image on the surface of the media;
A three-dimensional ink jet printer.
The print coordinates acquired by the print coordinate acquisition means are the print coordinates between the start print coordinates and the end print coordinates out of the print coordinates where the coordinate difference of all axes is the same, and the start print coordinates and the end When a compression number indicating the number of discarded print coordinates is set in any one of the print coordinates, between the coordinate value of each axis in the start print coordinate and the coordinate value of each axis in the end print coordinate Further comprising a developing means for expanding the coordinate value obtained by equally dividing the compression number by the number obtained by adding 1 as the discarded print coordinates.
The three-dimensional inkjet printer according to claim 8.
An image data acquisition step for acquiring image data for printing to be printed on a medium;
Print coordinate acquisition for acquiring the print coordinates of each print position at the rotation position of the medium in which the print positions at which ink droplets are ejected from the inkjet head are specified at regular intervals and the tangent line of each print position faces the horizontal direction Steps,
The print coordinates acquired in the print coordinate acquisition step are the print coordinates between the start print coordinates and the end print coordinates among the print coordinates in which the coordinate difference of all axes is the same, and the start print coordinates and the end When a compression number indicating the number of discarded print coordinates is set in any one of the print coordinates, between the coordinate value of each axis in the start print coordinate and the coordinate value of each axis in the end print coordinate Expanding the coordinate value obtained by equally dividing the compression number by the number obtained by adding 1 as the discarded print coordinates;
Based on the image data for printing acquired in the image data acquisition step, the print coordinates acquired in the print coordinate acquisition step, and the print coordinates expanded in the expansion step, the inkjet is performed while rotating a three-dimensional shape medium. A printing step of printing an image on the surface of the medium by discharging ink droplets from a head;
A printing method for a three-dimensional ink jet printer.