METHOD AND SYSTEM FOR PRINTING ON TILTED PRINT MEDIUM USING PRINTHEAD

Abstract

A method for printing on a tilted print medium using a first printing strategy or a second printing strategy. The first printing strategy includes: acquiring a tilted direction and a tilted angle of the titled print medium; acquiring a print start point; starting print from the start point and continuously translating the printhead toward the tilted opposite side in a direction perpendicular to the moving direction of the tilted print medium, and during the translation, controlling the inkjet hole to delay ink-jetting in the direction parallel to the moving direction of the tilted print medium. The second printing strategy includes: determining a tilted angle of the print medium and a position of a print standard point after tilted, adjusting the print content to be mirror symmetrical with the print medium, and controlling the printhead to print according to the print content when the print standard point reaches the printhead.

Claims

1. A method for printing on a tilted print medium using a printhead, adopting a first printing strategy, wherein a print medium is moved relative to the printhead and is printed when passing through the printhead, the print medium is referred to a untitled print medium before it is titled, and the print medium is referred to a titled print medium when it is titled; the untitled print medium is formed, by the printhead, multi-column linear print points perpendicular to a moving direction of the print medium, and the printhead is provided with a plurality of inkjet holes corresponding to the print points, the first printing strategy comprises Steps of: S1: acquiring a tilted state of the tilted print medium, including a tilted direction and a tilted angle α relative to the moving direction; S2: acquiring a print start point Z.sub.0 of the tilted print medium; S3: starting print, by the printhead, from the start point Z.sub.0 and translating the printhead, continuously, toward a tilted opposite side in a direction perpendicular to the moving direction of the tilted print medium, and controlling one or more inkjet holes to delay ink-jetting in a direction parallel to the moving direction of the tilted print medium; and S4: forming a complete pattern on the tilted print medium, which is not deformed due to the tilted print medium;

2. The method of claim 1, wherein in the first printing strategy, the tilted print medium is moved relative to the printhead at speed V.sub.X and is printed as passing through the printhead, in Step S3, the printhead is translated, continuously, toward the tilted opposite side with speed V.sub.Y relative to the tilted print medium in the direction perpendicular to the moving direction of the tilted print medium, which forms that a plurality of the inkjet holes corresponding to each column of print points of the tilted print medium is ink jetted with a sequential time delay of Δt, from the tilted opposite side to the other side; and V.sub.Y and Δt are set according to α.

3. The method of claim 2, wherein a print point closest to the printhead in each column of print points mapped on the tilted print medium is marked as point A.sub.1, and a print point farthest from the point A.sub.1 in the same column is marked as point A.sub.2, a distance between the point A.sub.1 and point A.sub.2 in the direction perpendicular to the moving direction of the tilted print medium is marked as ω, and the number of a column of inkjet holes corresponding to a column of print points as N, it is satisfied that V.sub.Y=V.sub.X tan α, $\Delta t=\frac{\omega \sin \alpha }{V_X\left(N-1\right)}.$

4. The method of claim 3, wherein the printhead is provided with multiple columns of inkjet holes with different spacing or spacing between the inkjet holes in the printhead is adjustable, the spacing between adjacent inkjet holes in the plurality of inkjet holes forming each column of print points on the untilted print medium is marked as L.sub.1, a time interval of the print points closest to the printhead in the adjacent column of print points of the tilted print medium printed by the printhead is set as ΔT′=θ T cos α prior to the Step S3, and the spacing of the inkjet holes is selected or the spacing of the inkjet holes is adjusted as L′.sub.1=V.sub.X ΔT sin α+L.sub.1 cos α, wherein the ΔT is an inkjet interval for printing print points in adjacent columns of the untitled print medium.

5. The method of claim 2, wherein a print point closest to the inkjet head in the last column of the print points corresponding to the untilted print medium on the tilted print medium is marked as a final reference point A.sub.1′, and a print point in the same column marked as the final reference point A.sub.1′ and farthest from the final reference point is marked as a tail point A.sub.2′; in Step S3, ink-jetting is started from the final reference point A.sub.1′ when the printhead is moved at speed V.sub.Y to print and form a column of print points corresponding to the final reference point A.sub.1′, ink-jetting, by the remaining inkjet holes that together form the column of print points corresponding to the final reference point A.sub.1′, is started from the inkjet hole corresponding to the final reference point A.sub.1′ with a sequential time delay of Δt, and an inkjet hole which is finally ink-jetted corresponds to the tail point A.sub.z′ before completing printing.

6. The method of claim 1, wherein in the first printing strategy, translating the printhead to correspond to the print start point Z.sub.0 before printing the print start point Z.sub.0 in Step S3.

7. The method of claim 1, wherein a print point closest to the printhead in each column of print points on the tilted print medium is marked as a reference point A.sub.1, an inkjet hole matched with the reference point A.sub.1 corresponds to the reference point A.sub.1 one by one during translating the printhead in Step S3.

8. The method of claim 1, wherein in Step S2, acquiring the print start point Z.sub.0 mapped on the tilted print medium according to the tilted angle α of the tilted print medium and the known distance of the print area relative to an edge of the untilted print medium, and also acquiring a point Z.sub.1 in the same column of print points as the point Z.sub.0 and farthest from the print start point Z.sub.0.

9. The method of claim 1, wherein a distance between two print points of the multiple print points mapped on the tilted print medium farthest apart in the translating direction of the printhead is marked as D, the tilted angle of the titled print medium makes D is less than or equal to a width of at least one column of inkjet holes of the printhead in the translating direction.

10. A method for printing on a tilted print medium using a printhead, adopting a second printing strategy, which comprises Steps of: determining a tilted angle of the tilted print medium and a position of a print standard point of the tilted print medium, adjusting a print content according to the tilted angle and the position of the print standard point to make the print content mirror symmetrical with the print medium; and controlling the printhead to start printing on the untiled print medium according to the adjusted print content when the print standard point is conveyed to the printhead.

11. The method of claim 10, wherein the tilted angle is an angle between one edge of the print medium and a reference line, the one edge of the print medium corresponding to the tilted angle is an angled edge of the print medium; the reference line is a straight line parallel to a direction in which the print medium is conveyed; and the method for determining the tilted angle of the tilted print medium is that: when satisfying a condition Sc1, measuring vertical distances y.sub.2 and y.sub.3 from two points D.sub.2 and D.sub.3 on the reference line to the angled edge of the print medium, respectively, and determining the tilted angle of the print medium according to a horizontal coordinate x.sub.2 of the point D.sub.2, a horizontal coordinate x.sub.3 of the point D.sub.3, y.sub.2 and y.sub.3.

12. The method of claim 11, wherein the condition Sc1 is that a horizontal coordinate of the print standard point is x1; the print medium is of a rectangular shape; and the method for determining the position of the print standard point after tilted is that: when the print medium is tilted in a clockwise direction, determining the position of the print standard point after tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.z, y.sub.3 and a length of an edge of the print medium perpendicular to the angled edge; and when the print medium is tilted in a counterclockwise direction, determining the position of the print standard point after tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.2, y.sub.3.

13. The method of claim 11, wherein the angled edge is a long edge of the print medium closest to the reference line; and the method for determining the tilted angle of the titled print medium according to the horizontal coordinate x.sub.2 of point D.sub.2, the horizontal coordinate x.sub.3 of the point D.sub.3, y.sub.2 and y.sub.3 is that: determining the tilted angle according to relationship formula $\tan \theta =\frac{y_2-y_3}{x_3-x_2}$ when the print medium is tilted in the clockwise direction; and determining the tilted angle according to relationship formula $\tan \theta =\frac{y_3-y_2}{x_3-x_2}$ when the print medium is tilted in the counterclockwise direction; wherein, θ is the tilted angle, x.sub.2 and x.sub.3 meet x.sub.3>x.sub.2.

14. The method of claim 13, wherein when the print medium is tilted in the clockwise direction, the method for determining the position of the print standard point after tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.2, y.sub.3 and the length of the edge of the print medium perpendicular to the angled edge, is that: when the print medium is tilted in the clockwise direction, determining the position of the print standard point after the print medium is tilted according to $y_1=\left(y_3+\frac{b}{\cos \theta }\right)-\left(x_3-x_1\right)\times \tan \theta ;$ and when the print medium is tilted in the counterclockwise direction, the method for determining the position of the print standard point after tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.2, y.sub.3, is that: when the print medium is tilted in the counterclockwise direction, determining the position of the print standard point after the print medium is tilted according to y.sub.1=y.sub.2+(x.sub.1−x.sub.2)×tan θ; wherein, y.sub.1 is the vertical height of the print standard point to the reference line, b is the length of the short edge of the print medium, x.sub.1, x.sub.2 and x.sub.3 meet x.sub.1>x.sub.3>x.sub.2.

15. A system for printing on a tilted print medium using a printhead, comprising a first device module combination, which comprises: a printhead, wherein a print medium is moved relative to the printhead and is printed when passing through the printhead, the print medium is referred to a untitled print medium before it is titled, and the print medium is referred to a titled print medium when it is titled; the printhead is provided with a plurality of inkjet holes, the plurality of inkjet holes is printed on the untilted print medium to form multi-column linear print points; a tilt detector, which is configured for detecting parameters, including a tilted direction and a tilted angle α of the tilted print medium relative to a moving direction of the titled print medium, which indicate a tilted state of the tilted print medium; a translating driver, which is configured for driving the printhead to translate in a direction perpendicular to the moving direction of titled print medium; a time delay controller, which is configured for controlling to delay ink-jetting of the inkjet holes of the printhead; and a control device, which includes a print point positioning module for at least acquiring a print start point Z.sub.0 for ink-jetting the tilted print medium, wherein the control device is connected to the tilt detector, the translating driver and the time delay controller, the printhead is controlled to translate by the translating driver, and one or more of inkjet holes in the printhead is controlled to delay ink-jetting by the time delay controller; or, a second device module, comprising a control module and a data processing module; the data processing module is used to determine a tilted angle of the tilted print medium and a position of a print standard point of the titled print medium; the control module is used to adjust a print content according to the tilted angle and the position of the print standard point determined by the data processing module to make the print content mirror symmetrical with the print medium; and the control module is also used to control the printhead to start printing on the print medium according to the print content when the print standard point is conveyed to the printhead.

16. The system of claim 15, wherein in the first device module combination, the titled print medium is moved relative to the printhead at speed V.sub.X and is printed as passing through the printhead, the translating driver is adapted to control the printhead to translate continuously toward the tilted opposite side with speed V.sub.Y relative to the tilted print medium in a direction perpendicular to the moving direction of the tilted print medium, which forms that a plurality of inkjet holes corresponding to each column of print points of the tilted print medium is ink-jetted with a sequential time delay of Δt from a tilted opposite side to the other side; and V.sub.Y and Δt are set according to α.

17. The system of claim 16, wherein the print point positioning module, cooperated with the tilt detector which detects data and a distribution of a known print area on the untilted print medium, is adapted to acquire two terminal print points at both ends in each column of print points, and a distance co between the two terminal print points in the direction perpendicular to the moving direction of the print medium, the control device is also configured to acquire the number N.sub.1 of inkjet holes to form the corresponding column of print points and set V.sub.Y=V.sub.X tan α and $\Delta t=\frac{\omega \sin \alpha }{V_X\left(N-1\right)}.$

18. The system of claim 17, wherein the printhead is provided with multiple columns of inkjet holes with different spacing or spacing between inkjet holes in the printhead is adjustable, the spacing between adjacent inkjet holes in a plurality of inkjet holes forming each column of print points on the untilted print medium is marked as L.sub.1, and the control device, according to the data acquired by the tilt detector and the print point positioning module, is configured to set a time interval of the print points closest to the printhead in the adjacent column of print points of the tilted print medium printed by the printhead as ΔT′=ΔT cos α, and select the inkjet hole spacing or adjust the inkjet hole spacing as L′.sub.1=V.sub.X ΔT sin α+L.sub.1 cos α, wherein the ΔT is an inkjet interval for printing the print points in adjacent columns of the untilted print medium.

19. The system of claim 15, wherein in the second device module combination, the tilted angle is an angle between one edge of the print medium and a reference line, the one edge of the print medium corresponding to the tilted angle is an angled edge of the print medium; the reference line is a straight line parallel to a direction in which the print medium is conveyed; the data processing module includes a data computing module, and a data detecting and measuring module; the data processing module is used to determine the tilted angle of the print medium, in a way that: the data detecting and measuring module is used to detect whether a condition Sc1 is satisfied or not, and when satisfying the condition Sc1, vertical distances y.sub.2 and y.sub.3 from two points D.sub.2 and D.sub.3 on the reference line to the angled edge of the print medium, respectively, is measured; and the data computing module is used to determine the tilted angle of the print medium according to a horizontal coordinate x.sub.2 of the point D.sub.2, a horizontal coordinate x.sub.3 of the point D.sub.3, the vertical distances y.sub.2 and y.sub.3.

20. The system of claim 19, wherein the condition Sc1 is that a horizontal coordinate of the print standard point is x1; the print medium is of a rectangular shape; the data processing module is used to determine the position of the print standard point after tilted, in a way that: the data computing module is used to determine the position of the print standard point after the print medium is tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.2, y.sub.3 and a length of an edge of the print medium perpendicular to the angled edge when the print medium is tilted in a clockwise direction; and the data computing module is also used to determine the position of the print standard point after tilted according to x.sub.1, x.sub.2, x.sub.3, y.sub.2, y.sub.3 when the print medium is tilted in a counterclockwise direction.

Description

DESCRIPTION OF THE DRAWINGS

[0083] FIG. 1 is a schematic diagram of printing on the untilted print medium according to embodiments 1 and 2 of the present invention.

[0084] FIG. 2 is a schematic diagram of printing on the tilted print medium according to embodiments 1 and 2 of the present invention.

[0085] FIG. 3 is a simplified schematic diagram of printing on the untilted print medium according to embodiments 1 and 2 of the present invention.

[0086] FIG. 4 is a simplified schematic diagram (I) of printing on the tilted print medium according to embodiments 1 and 2 of the present invention.

[0087] FIG. 5 is another simplified schematic diagram (II) of printing on the tilted print medium according to embodiments 1 and 2 of the present invention.

[0088] FIG. 6 is a schematic diagram of the geometric relationship of the print points before and after the occurrence of tilting of the print medium according to embodiments 1 and 2 of the present invention.

[0089] FIG. 7 is a schematic diagram of the overall structure of the printing system according to embodiment 3 of the present invention.

[0090] FIG. 8 is a schematic diagram of the structure of the print medium according to embodiment 3 of the present invention.

[0091] FIG. 9 is a schematic diagram of the overall structure of the printing system according to embodiment 4 of the present invention.

[0092] FIG. 10 is a schematic diagram of the structure of the print medium according to embodiment 4 of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0093] The accompanying drawings of the present invention are for exemplary illustration only and are not to be interpreted as limiting the present invention. In order to better illustrate the following embodiments, certain parts of the accompanying drawings are omitted, enlarged or reduced and do not represent the dimensions of the actual product; it is understandable to those skilled in the art that certain well-known structures and their descriptions may be omitted from the accompanying drawings.

Embodiment 1

[0094] As shown in FIGS. 1 and 2, a method for printing on a tilted print medium using a printhead is provided according to one embodiment. The print medium 1 placed on a conveyor 2 can be moved at a speed V.sub.X relative to the printhead 3 and is printed during passing through the printhead 3. The printhead 3 forms multi-column linear print points perpendicular to a moving direction of the print medium on the untilted print medium, and the printhead 3 is correspondingly provided with columns of inkjet holes to form the print points. The print point mapped substantially on the tilted print medium is the inkjet position preserved. The print point in this embodiment is represented in the shape of a circle for the sake of ease of representation. The printhead is connected to a tilt detector 4, a translating driver 5 and a time delay controller 6, a control device 7 and a distance sensor 8. The translating driver 5 is configured to driver the printhead 3 to translate in a direction perpendicular to the moving direction of print medium 1. The time delay controller 6 is configured to control to delay ink-jetting of the inkjet holes of the printhead 3. The control device 7 includes a print point positioning module consisting of print point positioning modules, and is also used to issue commands to control the translating driver 5 and the time delay controller 6.

[0095] Specifically, in this embodiment, the printing medium 1 is a rectangular ceramic tile, and the printing area is the entire top surface of the ceramic tile 1. the method according to the present embodiment includes four Steps.

[0096] In Step S1, a tilted direction and a tilted angle α of the tilted print medium 1 relative to the moving direction of the print medium 1 is acquired by the tilt detector 4. As shown in FIG. 2, the tilted direction includes a first direction and a second direction, in which (+) indicates the first direction and (−) indicates the second direction. Specifically, in this embodiment, the tilted angle α is less than or equal to 15°.

[0097] In Step S2, according on the known ceramic tile dimensions, the print area which the untilted print medium 1 maps onto the tilted print medium 1 is acquired, wherein the print point closest to printhead 3 in the print area is marked as the start point Z.sub.0, and the start point Z.sub.0 is acquired by the print point positioning module of the control device 7. Before the printhead 3 prints the start point Z.sub.0, the printhead 3 is firstly moved to make that, the inkjet hole N.sub.1 which jets ink to the corresponding print point of the untilted print medium 1 corresponding to the start point Z.sub.0 matches with the start point Z.sub.0 of the tilted print medium in the moving direction, as shown in FIG. 2.

[0098] In Step S3, the time for the print medium to reach the printhead 3 is calculated according to the distance sensor 8, the printhead 3 is started printing from the start point Z.sub.0 and is continuously translated at a specific speed V.sub.Y, relative to the tilted print medium in a direction perpendicular to the moving direction of the tilted print medium, towards the tilted opposite side of the tilted print medium. As shown in FIG. 2, in this embodiment, the print medium is tilted in the first direction, and the printhead is translated in the second direction opposite to the first direction. During the translation, ink is jetted to the tilted print medium to form that a plurality of inkjet holes in the same column of print points of the untilted print medium jet ink from the inkjet holes closest to the tilted opposite side to the inkjet holes closest to the tilted side with a sequential time delay of Δt. For illustrative purposes, as shown in FIG. 4, when printing to form the first print point pattern, the subsequent inkjet holes are jetted ink in sequence with a delay following the ink-jetting of N.sub.1 at the moment T. Therefore, the second inkjet hole jets ink at the moment T+Δt, and the third inkjet hole jets ink at the moment T+2 Δt. □t is the time interval of the delayed ink-jetting compared to the previous inkjet hole.

[0099] The print point closest to the printhead in each column of the print points mapping on the tilted print medium is marked as a reference point A.sub.1, the reference point in the last column is marked as the final reference point A.sub.1′, the print point, which is in the same column as the final reference point A.sub.1′ and is farthest from the final reference point, is marked as a tail point A.sub.2′. V.sub.Y and □t are set according to α. As shown in FIG. 3, in this embodiment at least the following are satisfied: the inkjet holes, which jet ink to the print points of the untilted print medium corresponding to each reference point A.sub.1, corresponds to the reference point A.sub.1 one by one during the movement of the printhead at speed V.sub.Y, thus achieving a precise printing process. The ink-jetting is started from the final reference point A.sub.1′ when the printhead moves at speed V.sub.Y to print and form the print point of the column corresponding to the final reference point A.sub.1′, the ink-jetting, by the remaining inkjet holes that together form the print points of the column corresponding to the final reference point A.sub.1′, is started from the inkjet hole corresponding to the final reference point A.sub.1′ with a sequential time delay of Δt, and delayed until that the inkjet hole of the final inkjet corresponds to the tail point A.sub.2′ before completing the print.

[0100] Specifically, in this embodiment, V.sub.Y and □t may be acquired based on a calculation of the detected parameters and the known parameters. The print point closest to the printhead in each column of print points mapped on the tilted print medium is acquired and marked as point A.sub.1 and the print point farthest from point A.sub.1 in the same column as point A.sub.2, the distance between the point A.sub.1 and point A.sub.2 in the direction perpendicular to the moving direction of the tilted print medium is marked as ω. In this embodiment, the print point positioning module and the tilt detector acquires the point Z.sub.0 in the first column and the point Z.sub.1 in the same column and farthest from the point Z.sub.0 incorporating the size of the known ceramic tile, and the number of a column of inkjet holes corresponding to and forming the same column of print points is marked as N, then V.sub.Y=V.sub.X tan α and

[00012]$t=\frac{\mathrm{\omega sin\alpha }}{V_X\left(N-1\right)}.$

[0101] In Step S4, a complete pattern on the tilted print medium is formed, and the pattern is not deformed due to the tilted print medium.

[0102] In addition to the above-mentioned performing the print of the tilted print medium adopting the same arrangement of the inkjet holes which print the untilted print medium, the printhead in this embodiment can include a plurality of columns of inkjet holes with different spacing or spacing between inkjet holes of printhead can be adjustable (not shown in the figure). The spacing between adjacent inkjet holes in a plurality of inkjet holes forming a column of print points on the untilted print medium is marked as L.sub.1. The time interval of the print points closest to the printhead in the adjacent column of print points of the tilted print medium printed by the printhead is set as ΔT′=ΔT cos α prior to S3. The spacing of the inkjet holes is selected or is adjusted as L′.sub.1=V.sub.X ΔT sin α+L.sub.1 cos α, wherein □T is the inkjet interval for printing the print points in adjacent columns of the untilted print medium, and L.sub.1 and ΔT are all known. The geometric relationships are specifically shown in FIGS. 5 and 6. For ease of representation, only a small number of print points are shown in FIG. 6, dotted print points are solid print points that map on the print medium after tilted at an angle α. This method allows more accurate reproduction of printing on the untilted print medium.

Embodiment 2

[0103] Referring back to FIGS. 1 and 2, a system for printing on a tilted print medium using a printhead is further provided. The print medium 1 placed on a conveyor 2 and can be moved at a speed V.sub.X relative to the printhead 3 and is printed during passing through the printhead 3. The printhead 3 forms multiple columns of linear and equally spaced print points perpendicular to a moving direction of the print medium on the untilted print medium, and the printhead 3 is correspondingly provided with columns of inkjet holes to form the print points. The print point mapped substantially in the tilted print medium is the inkjet position preserved. The print point in his embodiment is represented in the shape of a circle for easy representation. The printhead 3 is connected to a tilt detector 4, a translating driver 5 and a time delay controller 6, a control device 7 and a distance sensor 8. The control device 7 includes a print point positioning module consisting of print point positioning modules. Specifically, in this embodiment, the printing medium 1 is a rectangular ceramic tile, and the printing area is the entire top surface of the ceramic tile 1.

[0104] The tilt detector 4 is configured to acquire a tilted direction and a tilted angle α of the tilted print medium 1 relative to the moving direction of the print medium 1. As shown in FIG. 2, the tilted direction includes a first direction and a second direction, in which (+) indicates the first direction and (−) indicates the second direction. Specifically, in this embodiment, the tilted angle α is less than or equal to 15°. The print point positioning module in the control device 7, according on the known ceramic tile dimensions, cooperates with the tilt detector 4 to detect data to compute and acquire the print area which the untilted print medium 1 maps onto the tilted print medium 1, and to position the print point closest to the printhead 3 in the print area as the start point Z.sub.0. The control device 7 is configured to driver the printhead by the translating driver 5 to move firstly, before printing the start point Z.sub.0, to that, the inkjet hole N.sub.1 which jets ink to the corresponding print point of the untilted print medium 1 corresponding to the start point Z.sub.0 matches with the start point Z.sub.0 of the tilted print medium in the moving direction to, as shown in FIG. 2.

[0105] The control device 7 combines the results detected by the tilt detector 4 and the data of the print point positioning module to calculate the time for the print medium to reach the printhead, enabling the printhead to start printing from the start point Z.sub.0 and to continuously translate at a specific speed V.sub.Y, relative to the tilted print medium in a direction perpendicular to the moving direction of the tilted print medium, towards the tilted opposite side of the tilted print medium. As shown in FIG. 2, in this embodiment, the print medium is tilted towards the first direction, and the printhead is translated towards the second direction opposite to the first direction. During the translation, the control device 7 controls via the time delay controller 6 to jet ink to the tilted print medium to form that a plurality of inkjet holes in the same column of print points of the untilted print medium jet ink from the inkjet holes closest to the tilted opposite side to the inkjet holes closest to the tilted side with a sequential time delay of Δt. For illustrative purposes, as shown in FIG. 4, when printing to form the first print point pattern, the subsequent inkjet holes are jetted ink in sequence with a delay following the ink-jetting of N1 at the moment T. Therefore, the second inkjet hole jets ink at the moment T+Δt, and the third inkjet hole jets ink at the moment T+2 Δt. □t is the time interval of the delayed ink-jetting compared to the previous inkjet hole.

[0106] The print point closest to the printhead in each column of the print points mapping on the tilted print medium is marked as a reference point A.sub.1, the reference point in the last column is marked as the final reference point A.sub.1′, the print point, which is in the same column as the final reference point A.sub.1′ and is farthest from the final reference point, is marked as a tail point A.sub.2′. V.sub.Y and □t are set according to α. As shown in FIG. 3, in this embodiment at least the following are satisfied: the inkjet hole N.sub.1, which jets ink to the print points of the untilted print medium corresponding to each reference point A.sub.1, corresponds to the reference point A.sub.1 one by one during the movement of the printhead at speed V.sub.Y, thus achieving a precise printing process. The ink-jetting is started from the final reference point A.sub.1′ when the printhead moves at speed V.sub.Y to print and form the print point of the column corresponding to the final reference point A.sub.1′, the ink-jetting, by the remaining inkjet holes that together form the print point of the column corresponding to the final reference point A.sub.1′, is started from the inkjet hole corresponding to the final reference point A.sub.1′ with a sequential time delay of Δt, and delayed until that the inkjet hole of the final inkjet corresponds to the tail point A.sub.2′ before print completion.

[0107] Specifically, in this embodiment, V.sub.Y and □t may be acquired based on a calculation of the detected parameters and the known parameters. The print point closest to the printhead in each column of print points mapped on the tilted print medium is acquired and marked as point A.sub.1 and the print point farthest from the point A.sub.1 in the same column as point A.sub.2, the distance between the point A.sub.1 and point A.sub.2 in the direction perpendicular to the moving direction of the tilted print medium is marked as ω. In this embodiment, the point Z.sub.0 in the first column and the point Z.sub.1 in the same column and farthest from the point Z.sub.0 are acquired by the print point positioning module and the tilt detector 4 incorporating the size of the known ceramic tile, and the number of a column of inkjet holes corresponding to and forming the same column of print points is marked as N, then V.sub.Y=V.sub.X tan α,

[00013]$t=\frac{\mathrm{\omega sin\alpha }}{V_X\left(N-1\right)}.$

[0108] In particular, the printhead in this embodiment can include a plurality of columns of inkjet holes with different spacing or spacing between inkjet holes of printhead can be adjustable (not shown in the figure). The spacing between adjacent inkjet holes in a plurality of inkjet holes forming a column of print points on the untilted print medium is marked as L1. The control device set, based on the data acquired by the tilt detector and the print point positioning module, the time interval of the print points closest to the printhead in the adjacent column of print points of the tilted print medium printed by the printhead as ΔT′=ΔT cos α. The spacing of the inkjet holes is selected or is adjusted as L′.sub.1=V.sub.X ΔT sin α+L.sub.1 cos α, wherein ΔT is the inkjet interval for printing the print points in adjacent columns of the untilted print medium and L.sub.1 and ΔT are all known. Specifically, the geometric relationships are shown in FIGS. 5 and 6. For easy representation, only a small number of print points are shown in FIG. 6, dotted print points are solid print points that map on the print medium after tilted at an angle α. This method allows more accurate reproduction of printing on the untilted print medium.

[0109] The printhead continues to translate until the print pattern is completed to print on the tilted print medium, and the pattern is not deformed due to the tilted print medium, achieving the same print effect as on the untilted print medium.

Embodiment 3

[0110] As shown in FIG. 7, a printing system for handling a tilted print medium is provided according to one embodiment, applying to a rectangular print medium ABCE. The tilted direction of the rectangular print medium ABCE is in a clockwise direction, and the system includes a data processing module and a control module.

[0111] As shown in FIG. 7, the printing system also involves interaction with a printhead 100 and a print content 200, wherein, the printhead 100 forms a pattern or color on the print medium ABCE according to the preset print content 200. The print content 200 is generally a pattern or design set in the software, however the print content 200 is not an entity. In this embodiment, the print content 200 is embodied in FIG. 7 for illustrative purposes only.

[0112] The data processing module is used to acquire a tilted state of the print medium ABCE, the control module is used to adjust the print content 200 according to the tilted state acquired by the data processing module and control the printhead 100 to form a pattern and/or color on the print medium ABCE according to the print content 200.

[0113] The specific processing and adjusting Steps of the data processing module and the control module are as follows.

[0114] S1: acquiring, by the data processing module, the tilted state of the print medium ABCE, the tilted state including a tilted angle of the print medium ABCE and a position of a print standard point B of the print medium ABCE;

[0115] S21: adjusting, by the control module, a print content 200 according to the tilted state of the print medium ABCE acquired by the data processing module in Step S1, to make the print content mirror symmetrical with the print medium ABCE; performing Step S22 when the print standard point Bis conveyed to the printhead 100; and

[0116] S22: controlling, by the control module, the printhead 100 to start printing on the print medium ABCE according to the print content 200 adjusted according to Step S21 until the printing is completed.

[0117] The system provided by this embodiment may cooperate with the control module to adjust the print content corresponding to the tilted print medium after only needs the data processing module to calculate or measure to acquire the tilted state of the print medium, such that the printing of the tilted print medium may be completed smoothly, and the entire adjustment process is non-manual, efficient and cost-effective.

[0118] As a preferred solution, shown in FIG. 8, the tilted angle is θ, which is the angle between the edge CE of the print medium ABCE and a reference line l, thus, the edge CE is also marked as an angled edge CE, the reference line is a straight line parallel to the direction in which the print medium is conveyed. Furthermore, θ in this embodiment and the following embodiment is the same angle as a of the abovementioned embodiments.

[0119] The data processing module includes a data computation module, and a data detection and measurement module. The data detection and measurement module includes an obstruction sensor, a first distance sensor and a second distance sensor. As shown in FIG. 8, the three sensors are all set on the reference line l, where the obscuration sensor is set at the point D.sub.1, the first distance sensor is set at the point D.sub.2, and the second distance sensor is set at the point D.sub.3. The horizontal coordinates of the points D.sub.1, D.sub.2 and D.sub.3 are x.sub.1, x.sub.2 and x.sub.3 respectively.

[0120] The specific execution of Step S1 is as follows.

[0121] S11: detecting, by the obstruction sensor, whether the horizontal coordinate of the print standard point B is satisfied with the condition x.sub.1 or not; if satisfied, performing Step S12 by the first distance sensor and the second distance sensor;

[0122] S12: measuring, by the first distance sensor and the second distance sensor, the vertical distances y.sub.2 and y.sub.3 to the angled edge at the points D.sub.2 and D.sub.3 respectively; and

[0123] S13: determining, by the data computation module, the tilted angle θ according to the horizontal coordinate x.sub.2 of the point D.sub.2, the horizontal coordinate x.sub.3 of the point D.sub.3, y.sub.2 and y.sub.3 detected in Step S12, and determining the position of the print standard point B according to the horizontal coordinate x.sub.2 of the point D.sub.2, the horizontal coordinate x.sub.3 of the point D.sub.3, y.sub.2 and y.sub.3 detected in Step S12 and the length of the edge BC or edge AE.

[0124] The straight line with the points D.sub.2 and D.sub.3 as endpoints perpendicular to the reference line/has two junction points K and F with the angled edge CE, with none of the junction points overlapping with the two endpoints of the angled edge CE.

[0125] The specific execution of Step S1 includes calculating and acquiring the tilted angle θ according to relationship formula

[00014]$\tan \theta =\frac{y_2-y_3}{x_3-x_2},$

after determining the tilted angle θ, determining the position of the print standard point after the print medium is tilted according to

[00015]$y_1=\left(y_3+\frac{b}{\cos \theta }\right)-\left(x_3-x_1\right)\times \tan \theta ,$

where, b is the length of the edge BC or edge AE.

[0126] As shown in FIG. 8, It is known that □CBG, □KFJ and □HFG are equal to θ, with the calculation of mathematical geometry, relationship formula

[00016]$y_1=\left(y_3+\frac{b}{\cos \theta }\right)-\left(x_3-x_1\right)\times \tan \theta$

is acquired, where, y.sub.1 is the vertical height of the print standard point B to the reference line. After calculating y.sub.1, the exact position (x.sub.1, y.sub.1) of the print standard point B can be determined based on the horizontal coordinate x.sub.1 of the point D.sub.1.

Embodiment 4

[0127] As shown in FIG. 9, a printing system for handling a tilted print medium is provided according to one embodiment, applying to a rectangular print medium ABCE. The tilted direction of the rectangular print medium ABCE is in an anticlockwise direction, and the system includes a data processing module and a control module. As shown in FIG. 9, the printing system also involves interaction with a printhead 100 and a print content 200, wherein, the printhead 100 forms a pattern or color on the print medium ABCE according to the preset print content 200. The print content 200 is generally a pattern or design set in the software, however the print content 200 is not an entity. In this embodiment, the print content 200 is embodied in FIG. 9 for illustrative purposes only.

[0128] The data processing module is used to acquire a tilted state of the print medium ABCE, the control module is used to adjust the print content 200 according to the tilted state acquired by the data processing module and control the printhead 100 to form a pattern and/or color on the print medium ABCE according to the print content 200.

[0129] The specific processing and adjusting Steps of the data processing module and the control module are as follows.

[0130] S1: acquiring, by the data processing module, the tilted state of the print medium ABCE, the tilted state including a tilted angle of the print medium ABCE and a position of a print standard point C of the print medium ABCE;

[0131] S21: adjusting, by the control module, a print content 200 according to the tilted state of the print medium ABCE acquired by the data processing module in Step S1, to make the print content mirror symmetrical with the print medium ABCE; performing Step S22 when the print standard point C is conveyed to the printhead 100;

[0132] S22: controlling, by the control module, the printhead 100 to start printing on the print medium ABCE according to the print content 200 adjusted according to Step S21 until the printing is completed.

[0133] The system provided by this embodiment may cooperate with the control module to adjust the print content corresponding to the tilted print medium after only needs the data processing module to calculate or measure to acquire the tilted state of the print medium, such that the printing of the tilted print medium may be completed smoothly, and the entire adjustment process is non-manual, efficient and cost-effective.

[0134] As a preferred solution, shown in FIG. 10, the tilted angle is θ, which is the angle between the edge CE of the print medium ABCE and a reference line l, thus, the edge CE is also marked as an angled edge CE, the reference line is a straight line parallel to the direction in which the print medium is conveyed.

[0135] The data processing module includes a data computation module, and a data detection and measurement module. The data detection and measurement module includes an obstruction sensor, a first distance sensor and a second distance sensor. As shown in FIG. 10, the three sensors are all set on the reference line l, where the obscuration sensor is set at the point D.sub.1, the first distance sensor is set at the point D.sub.2, and the second distance sensor is set at the point D.sub.3. The horizontal coordinates of the points D.sub.1, D.sub.2 and D.sub.3 are x.sub.1, x.sub.2 and x.sub.3 respectively.

[0136] The specific execution of Step S1 including the following steps.

[0137] S11: detecting, by the obstruction sensor, whether the horizontal coordinate of the print standard point C is satisfied with the condition x.sub.1 or not; if satisfied, performing Step S12 by the first distance sensor and the second distance sensor;

[0138] S12: measuring, by the first distance sensor and the second distance sensor, the vertical distances y.sub.2 and y.sub.3 to the angled edge at the points D.sub.2 and D.sub.3, respectively; and

[0139] S13: determining, by the data computation module, the tilted angle θ and the position of the print standard point C according to the horizontal coordinate x.sub.2 of the point D.sub.2, the horizontal coordinate x.sub.3 of point the D.sub.3, y.sub.2 and y.sub.3 detected in Step S12.

[0140] The straight line with the points D.sub.2 and D.sub.3 as endpoints perpendicular to the reference line/has two junction points G and F with the angled edge CE, with none of the junction points overlapping with the two endpoints of the angled edge CE.

[0141] The specific execution of Step S13 includes calculating and acquiring the tilted angle θ according to relationship formula

[00017]$\tan \theta =\frac{y_3-y_2}{x_3-x_2},$

after determining the tilted angle θ, determining the position of the print standard point C after the print medium is tilted according to y.sub.1=y.sub.2+(x.sub.1−x.sub.2)×tan θ.

[0142] As shown in FIG. 10, it is known that CEI and CGH are equal to θ, with the calculation of mathematical geometry, relationship formula y.sub.1=y.sub.2+(x.sub.1−x.sub.2)×tan θ is acquired, where, y.sub.1 is the vertical height of the print standard point C to the reference line. After calculating y.sub.1, the exact position (x.sub.1, y.sub.1) of the print standard point C can be determined based on the horizontal coordinate x.sub.1 of the point D.sub.1.

[0143] Obviously, the above embodiments of the present invention are merely illustrative examples for the purpose of clearly illustrating the technical solution of the present invention, and are not intended to limit the embodiments of the present invention in a specific manner. Any modification, equivalent replacement and improvement, etc. made within the spirit and principles of the claims of the present invention shall be included within the scope of protection of the claims of the present invention.