Screen printing method and device therefor

Patent metadata

Field	Value
Publication number	US-10926530-B2
Application number	US-201615774156-A
Country	US
Kind code	B2
Filing date	Nov 12, 2016
Priority date	Nov 14, 2015
Publication date	Feb 23, 2021
Grant date	Feb 23, 2021

Abstract

A printing object surface has a cross-sectional shape curving along a printing advancing direction. The printing advancing direction is defined as a Y-axis, a direction orthogonal to the Y-axis and belonging to the cross-section is defined as a Z-axis, and a direction around an axis orthogonal to a Y-Z plane is defined as a θ-axis. A squeegee is disposed so as to be movable in the respective Y-, Z- and θ-axis directions. Information indicating a mutual relationship among respective Y-, Z- and θ-axis positions is obtained. The relationship is a relationship that enables performing printing while maintaining or substantially maintaining an angle formed by a direction tangent to a printing position in the printing object surface in the Y-Z plane and the squeegee. Printing is executed while the respective Y-, Z-, θ-axis positions of the squeegee relative to the printing object surface are controlled according to the obtained information.

First claim

The invention claimed is:

1. A screen printing method for screen printing on a printing object surface having a cross-sectional shape curving along a printing advancing direction, the method comprising:
where the printing advancing direction is defined as a Y-axis, a direction orthogonal to the Y-axis and belonging to the cross-section is defined as a Z-axis and a direction around an axis orthogonal to a Y-Z plane is defined as a θ-axis, and
where a position in the θ-axis direction corresponds to an angle around the axis orthogonal to the Y-Z plane with reference to a reference position around the axis orthogonal to the Y-Z plane,
providing a controller and a memory;
disposing a squeegee so as to be movable in respective Y-, Z- and θ-axis directions relative to the printing object surface;
storing information in the memory, the information being obtained based on data on the cross-sectional shape of the printing object surface or data on a shape approximating the cross-sectional shape, and the information indicating a mutual relationship among respective Y-, Z- and θ-axis positions, the mutual relationship enabling performing printing while maintaining or substantially maintaining a printing angle formed by a direction tangent to a printing position in the printing object surface in the Y-Z plane and the squeegee, and the controller adjusting the position of the squeegee in the θ-axis direction based upon the mutual relationship such that the printing angle formed by the direction tangent to the printing position in the printing object surface in the Y-Z plane and the squeegee is maintained or substantially maintained; and
executing printing while controlling with the controller the respective Y-, Z- and θ-axis positions of the squeegee relative to the printing object surface according to the stored information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions.

2. The screen printing method according to claim 1 , comprising:
obtaining the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions before execution of printing and setting the information in advance; and
executing printing while controlling the respective Y-, Z- and θ-axis positions of the squeegee relative to the printing object surface according to the set information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions.

3. The screen printing method according to claim 1 , wherein the data on the cross-sectional shape of the printing object surface or the data on the shape approximating the cross-sectional shape is CAD data.

4. The screen printing method according to claim 1 , wherein the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions is obtained as information with variation in the Y-axis position and the Z-axis position due to variation in the θ-axis position taken into consideration.

5. The screen printing method according to claim 1 , wherein the printing is executed using a screen having a cross-sectional shape curving along the printing advancing direction so as to follow or substantially follow the printing object surface.

6. The screen printing method according to claim 1 , wherein the printing is executed while a printing speed in the direction tangent to the printing position in the printing object surface in the Y-Z plane is maintained or substantially maintained.

7. The screen printing method according to claim 6 , wherein control of the printing speed is performed by obtaining the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions for each of positions with an interval of a predetermined distance along the printing object surface before execution of printing, setting the information in advance, and sequentially reading the information at a time interval according to a designated printing speed and providing the information as position instruction values for the respective Y, Z, θ-axes to control the respective axes.

8. The screen printing method according to claim 1 , comprising:
providing the controller with a servo motor, the controller being configured to rotate the squeegee in the θ-axis direction about a rotational shaft via the servo motor.

9. A screen printing device for screen printing on a printing object surface having a cross-sectional shape curving along a printing advancing direction,
where the printing advancing direction is defined as a Y-axis, a direction orthogonal to the Y-axis and belonging to the cross-section is defined as a Z-axis and a direction around an axis orthogonal to a Y-Z plane is defined as a θ-axis, and
where a position in the θ-axis direction corresponds to an angle around the axis orthogonal to the Y-Z plane with reference to a reference position around the axis orthogonal to the Y-Z plane, the apparatus comprising:
a controller;
a memory;
a squeegee;
a doctor; and
a mover that moves the squeegee relative to the printing object surface in respective Y-, Z- and θ-axis directions;
the memory storing information obtained based on data on the cross-sectional shape of the printing object surface or data on a shape approximating the cross-sectional shape, and the information indicating a mutual relationship among respective Y-, Z- and θ-axis positions, the mutual relationship enabling performing printing while maintaining or substantially maintaining a printing angle formed by a direction tangent to a printing position in the printing object surface in the Y-Z plane and the squeegee, and at a time of printing via the squeegee, the controller controls the mover according to the information stored in the memory so as to control the respective Y-, Z- and θ-axis positions of the squeegee relative to the printing object surface to be respective positions according to the information, and wherein
the controller is configured to adjust the position of the squeegee in the θ-axis direction via the mover and based upon the information stored in memory indicating the mutual relationship such that the printing angle formed by the direction tangent to the printing position in the printing object surface in the Y-Z plane and the squeegee is maintained or substantially maintained.

10. The screen printing device according to claim 9 , comprising the memory storing, in advance, the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions in a form of information that is a combination of positional data of the respective Y-, Z- and θ-axis positions.

11. The screen printing device according to claim 10 , wherein:
the memory stores the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions for each of positions with an interval of a predetermined distance along the printing object surface; and
the controller sequentially reads the information indicating the mutual relationship among the respective Y-, Z- and θ-axis positions at a time interval according to a designated printing speed, from the memory and provides the information as position instruction values for the respective Y-, Z- and θ-axes to control the respective axes.

12. The screen printing device according to claim 9 , wherein:
the mover includes a mechanism that moves the squeegee and the doctor together in the respective Y-, Z- and θ-axis directions relative to the printing object surface; and
the controller obtains the information indicating the mutual relationship among respective Y-, Z- and θ-axis positions from the memory so as to enable returning of an ink while maintaining or substantially maintaining an angle formed by a direction tan

Assignees

• Murakami Corp

Inventors

• Fukazawa Akihiko
• HOMMA Yoshihito

Classifications

• B41F15/46

  with two or more operative parts · CPC title

• B41F15/423

  Driving means for reciprocating squeegees · CPC title

• B41F15/42

  comprising squeegees or doctors · CPC title

• B41F15/30

  for articles with curved surfaces · CPC title

• B41F15/0895 Primary

  for printing on curved surfaces not otherwise provided for · CPC title