CN110914061B

CN110914061B - Screen printing apparatus and screen printing method

Info

Publication number: CN110914061B
Application number: CN201880051959.4A
Authority: CN
Inventors: 笠原隼人; 丸山充志; 深泽彰彦; 本间好人
Original assignee: Micro Tec Co Ltd; Murakami Co Ltd
Current assignee: Micro Tec Co Ltd; Murakami Co Ltd
Priority date: 2017-08-10
Filing date: 2018-07-23
Publication date: 2022-01-07
Anticipated expiration: 2038-07-23
Also published as: WO2019031207A1; KR102298276B1; TWI727192B; JP7054131B2; CN110914061A; TW201919915A; JP2019034416A; KR20200036864A

Abstract

A screen printing device for printing a workpiece (200) having a curved surface on the surface thereof by squeegee is provided with: a jig (400) on which the workpiece (200) is placed and which has a reference mark (410); a camera for photographing the reference mark (410) of the jig (400) and a printed line (201) of a printed pattern printed on the workpiece (200); and a control unit for analyzing the printing result by the image photographed by the camera.

Description

Screen printing apparatus and screen printing method

Technical Field

The present invention relates to a screen printing apparatus and a screen printing method for screen printing a workpiece having a curved surface.

Background

Conventionally, an apparatus for screen printing a workpiece having a curved surface has been conceived.

In addition, a screen printing apparatus using an articulated robot has been conceived.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-044330;

patent document 2: japanese patent laid-open No. 2014-172099;

patent document 3: japanese patent laid-open publication No. 2005-088577;

patent document 4: japanese patent laid-open publication No. 11-320820;

patent document 5: japanese patent laid-open publication No. H06-031895;

patent document 6: international publication No. 2017/005576.

Disclosure of Invention

Problems to be solved by the invention

The invention provides a screen printing apparatus and a screen printing method for accurately checking a printing result.

Means for solving the problems

The screen printing apparatus of the present invention is a screen printing apparatus for printing a workpiece having a curved surface on a surface thereof by squeegee, and includes:

a jig on which the workpiece is placed and which has a reference mark;

a camera for photographing the reference mark of the jig and the print pattern printed on the workpiece; and

and a control unit for analyzing the printing result by the image photographed by the camera.

Effects of the invention

According to the present invention, since the jig has the reference mark, the printing result can be correctly checked.

Drawings

Fig. 1 is a front view of a screen printing apparatus 100 in embodiment 1.

Fig. 2 is a left side view of the screen printing apparatus 100 in embodiment 1.

Fig. 3 is a right side view of the screen printing apparatus 100 in embodiment 1.

Fig. 4 is a partially omitted rear view of the screen printing apparatus 100 in embodiment 1.

Fig. 5 is a plan view of the screen printing apparatus 100 in embodiment 1.

Fig. 6 is a configuration diagram of an articulated robot 600 of the screen printing apparatus 100 according to embodiment 1.

Fig. 7 is a front view of a plate moving mechanism 700 of the screen printing apparatus 100 in embodiment 1.

Fig. 8 is a right side view of a plate moving mechanism 700 of the screen printing apparatus 100 in embodiment 1.

Fig. 9 is a front view and a right side view of an off-screen mechanism 800 of the screen printing apparatus 100 in embodiment 1. (a) Is a front view of off-grid mechanism 800 at the origin. (b) Is a front view with the table 820 raised. (c) Is a right side view with the table 820 horizontally raised.

Fig. 10 is a left side view of the screen separation mechanism 800 of the screen printing apparatus 100 in embodiment 1.

Fig. 11 is a right side view of the screen separation mechanism 800 of the screen printing apparatus 100 in embodiment 1.

Fig. 12 is a configuration diagram of a printing portion 900 of the screen printing apparatus 100 according to embodiment 1. (a) The printing unit 900 is mounted. (b) The printing unit 900 is removed.

Fig. 13 is a configuration diagram of a printing portion 900 of the screen printing apparatus 100 according to embodiment 1.

Fig. 14 is a configuration diagram of a printing portion 900 of the screen printing apparatus 100 according to embodiment 1.

Fig. 15 is a configuration diagram of the workpiece 200, the screen 300, and the jig 400 of the screen printing apparatus 100 in embodiment 1. (a) Is a constitutional view of the screen 300 and the workpiece 200 and the jig 400. (b) The workpiece 200 and the jig 400 are shown in the drawings. (c) A structure of the workpiece 200 is shown. (d) Is an explanatory view of the reference mark.

Fig. 16 is a partial configuration diagram of the screen printing apparatus 100 in embodiment 1.

Fig. 17 is a partial configuration diagram of a screen printing apparatus 100 in embodiment 1.

Fig. 18 is a partial configuration diagram of a screen printing apparatus 100 in embodiment 1.

Fig. 19 is an operation flowchart of the screen printing apparatus 100 according to embodiment 1.

Fig. 20 is a diagram illustrating a printing operation of the screen printing apparatus 100 according to embodiment 1.

Fig. 21 is a diagram illustrating a printing operation of the screen printing apparatus 100 according to embodiment 1.

Fig. 22 is a diagram illustrating a printing operation of the screen printing apparatus 100 according to embodiment 1.

Fig. 23 is an explanatory diagram of an operation of the screen separating mechanism 800 of the screen printing apparatus 100 according to embodiment 1. (a) The relationship between the workpiece 200 and the screen 300 is illustrated without operating the off-screen mechanism 800. (b) The relationship between the workpiece 200 and the screen 300 when the off-screen mechanism 800 is operated is shown.

Fig. 24 is an explanatory diagram of an operation of the screen separating mechanism 800 of the screen printing apparatus 100 according to embodiment 1. (a) The relationship between the workpiece 200 and the screen 300 is illustrated without operating the off-screen mechanism 800. (b) Is a relational diagram of the workpiece 200 and the screen 300 in the case where the vertical mechanism 830 is operated. (c) The relationship between the workpiece 200 and the screen 300 when the rotation mechanism 860 is operated is shown.

Detailed Description

Embodiment 1.

Description of the constituent

The configuration of the screen printing apparatus 100 will be described with reference to fig. 1, 2, 3, 4, and 5.

In fig. 1, a direction in the printing direction, i.e., a direction to the left of the paper surface is referred to as a forward direction.

In fig. 1, the direction opposite to the printing direction, i.e., the right direction toward the paper surface is referred to as the rear direction.

In fig. 1, the vertical direction on the paper surface is referred to as the height direction.

In fig. 1, the direction toward the front of the paper is referred to as the right direction.

In fig. 1, the depth direction on the paper surface is referred to as the left direction.

In fig. 1, two articulated robots 600 are shown, but actually, only one articulated robot 600 is present.

The screen printing apparatus 100 is an apparatus that performs screen printing on a workpiece 200 having a curved surface using a chase 310 having a screen 300.

The screen printing apparatus 100 includes a housing 500, an articulated robot 600, a plate transfer mechanism 700, a screen separation mechanism 800, and a printing unit 900.

< < frame 500>

The screen printing apparatus 100 includes a frame 500.

The frame 500 includes a base 510, a control box 520, a column frame 530, a beam frame 540, and a top plate 550.

The base 510 is a base of the screen printing apparatus 100.

The base 510 has a box-like shape.

The control box 520 houses the control unit 110 therein.

The column frame 530 is a column standing on the floor surface of the base 510.

The beam frame 540 is a beam connecting the tops of the column frames 530.

The ceiling 550 is a ceiling disposed between the beam frames 540.

The screen printing apparatus 100 has a roller holding portion 590.

The roller holding portion 590 rotatably holds the roller film. The roll film is a roll-like film of test print.

< < control unit 110>

The screen printing apparatus 100 has a control section 110.

The control unit 110 controls the entire apparatus.

The control unit 110 is realized by a central processing unit, a program, a memory, and a storage device.

The control unit 110 controls the monitor 120, the robot controller 130, the image processing unit 140, the vacuum pump 150, the instrument panel 170 shown in fig. 2, and the air pressure circuit 160 shown in fig. 5 shown in fig. 1 to control a printing operation and an inspection operation, which will be described later.

Signals from the control unit 110 are transmitted to each unit through signal lines.

Each operation of the printing method described later can be realized by the control unit 110 transmitting a command through a signal line.

< < articulated robot 600 >)

Fig. 6 shows a multi-joint robot 600.

The articulated robot 600 is one of industrial robots.

An industrial robot is a device that has a manipulation function or a movement function by automatic control, can execute various operations by a program, and can be used in industry.

An industrial robot has a manipulator and a storage device.

An industrial robot is a device capable of automatically performing work of extending, retracting, moving up and down, moving left and right, or circling of a manipulator or a composite motion thereof based on information of a storage device.

Here, the manipulator has a function similar to that of a human arm and can perform various tasks.

A multi-joint robot is one of joint robots.

The mechanical structure of the arm of the articulated robot is constituted by three or more rotary joints. That is, the joint robot has three or more degrees of freedom, and is a manipulator that can be automatically controlled or programmed.

The articulated robot 600 has a plurality of links and a plurality of joints.

The links are individual elements that constitute a mechanical structure and are capable of moving relative to each other.

The joint means a connection portion when two links are in contact with each other and relatively moved.

The articulated robot 600 shown in fig. 6 is a suspension type robot.

The articulated robot 600 shown in fig. 6 is a multi-axis robot having six rotational axes of an axis J1 to an axis J6 described below.

The multi-joint robot 600 has a base 610, a body 620, a shoulder 630, an upper arm 640, an elbow 650, a forearm 660, a wrist 670, and an end 680.

The body 620, upper arm 640, forearm 660, and tip 680 are links.

Shoulder 630, elbow 650, and wrist 670 are joints.

The base 610 is fixed to the ceiling 550 of the ceiling above the center of the printing width of the screen.

The base 610 has an axis J1 perpendicular to the top plate 550.

The axis J1 of the base 610 is a rotation axis orthogonal to the ceiling.

The axis J1 of the base 610 is disposed at the center upper portion of the printing width in the left-right direction of the screen 300.

The axis J1 of the base 610 is disposed above the printing range in the front-rear direction of the screen 300.

The main body 620 is attached to the base 610 so as to be rotatable about an axis J1 perpendicular to the ceiling.

The shoulder 630 is fixed to the body 620 and has a horizontal axis J2.

The upper arm 640 is attached to the shoulder 630 so as to be rotatable about a horizontal axis J2.

The elbow 650 is fixed to the upper arm 640 and has a horizontally oriented axis J3.

Additionally, the elbow 650 has an axis J4 that is perpendicular relative to the axis J3.

The forearm 660 is attached to the elbow 650 so as to be rotatable about the axis J3 and the axis J4.

The front arm 660 is rotatable about an axis J4 perpendicular to the horizontal axis J3 and intersecting the axis J3.

Wrist 670 has an axis J5 that is perpendicular relative to axis J4 and intersects axis J4.

In addition, wrist 670 has an axis J6 perpendicular to axis J5 and intersecting axis J5.

The tip 680 is attached to the forearm 660 so as to be rotatable about the axis J5 and the axis J6.

Each link attached to each shaft is rotated about each shaft by a motor not shown.

The rotation angle of each motor is controlled based on an electric signal output from the robot controller 130.

In fig. 6, the axes J1 and J2 are located above the printing stroke between the printing start position S1 and the printing end position S2.

The axis J1 is orthogonal to the printing direction and orthogonal to the axis J2.

The axis J2 is orthogonal to the printing direction and orthogonal to the axis J1.

The maximum angle formed by the straight line connecting the axis J2 and the print start position S1 and the straight line connecting the axis J2 and the print end position S2 may be an angle that changes when the size of the workpiece 200 changes, and is preferably 90 degrees or less, more preferably 50 degrees or less, and preferably 40 degrees.

< plate moving mechanism 700 >)

The plate moving mechanism 700 is a mechanism that moves the chase 310 in the horizontal direction.

The plate moving mechanism 700 moves the plate frame 310 after printing and opens the upper space of the workpiece 200.

As shown in fig. 7 and 8, the plate moving mechanism 700 has four legs 720 and two sliding mechanisms 730.

Each sliding mechanism 730 is fixed to the upper portion of two legs 720.

The slide mechanism 730 is provided with a conveyor belt 740 in the left-right direction.

The conveyor belt 740 is rotated by a motor 750 disposed at an end of one of the slide mechanisms 730.

The frame fixing portion 760 is slidably attached to the slide mechanism 730 on the left and right sides.

The frame fixing portion 760 detachably mounts the chase 310.

The frame fixing portion 760 slides to the left and right by the rotation of the conveyor belt 740.

In fig. 8, the state in which the chase 310 is moved to the leftmost side of the paper is a cap state in which the chase 310 covers the workpiece 200, and is a printable state.

In fig. 8, the state in which the chase 310 is moved to the right of the paper surface is an open state in which the upper space of the workpiece 200 is open, and is an inspectable state in which the printing result of the workpiece 200 can be inspected.

< < off-grid mechanism 800 >)

The off-grid mechanism 800 is explained with reference to fig. 9, 10, and 11.

Fig. 9 (a) is a view of the off-grid mechanism 800 at the origin, and the jig 400 is at the lowermost position.

Fig. 9 (b) is a view of lifting one end of the table 820 by hand with the off-grid mechanism 800 at the origin.

Fig. 9(c) is a view of the off-screen mechanism 800 horizontally lifting the table 820.

The off-screen mechanism 800 is a mechanism that moves the jig 400 relative to the chase 310.

The off-screen mechanism 800 changes the distance between the screen 300 and the jig 400.

The off-screen mechanism 800 mounts the jig 400 in such a manner that the distance between the jig 400 and the screen 300 can be changed.

The off-grid mechanism 800 has a frame 822 to which the jig 400 is fixed and a table 820 to which the frame 822 is fixed.

The table 822 is two four-corner posts made of aluminum or other metal.

The table 820 is a rectangular plate made of aluminum or other metal.

The off-screen mechanism 800 has an up-down mechanism 830 that moves the jig 400 up and down with respect to the screen 300.

The off-screen mechanism 800 has a rotation mechanism 860 that rotates the jig 400 relative to the screen 300.

< Up/Down mechanism 830>

The up-down mechanism 830 is fixed to the floor surface of the housing 500.

The up-down mechanism 830 includes a plurality of up-down cylinders arranged along the printing direction.

The fixture 400 is fixed to the stage 820 via a frame 822.

The up-down mechanism 830 has six up-down cylinders and eight linear shafts.

The up and down cylinders are used to move the table 820 up and down.

The upper and lower cylinders are actuators driven to extend and contract by hydraulic pressure, air pressure, hydraulic pressure, or electric power, and are preferably air cylinders.

The upper and lower cylinders have upper and lower shafts 839 that move up and down.

The linear axis supports the linear motion of the upper and lower cylinders, and vertically restricts the vertical movement of the table 820.

Each linear shaft has a linear movement shaft 849 that slides up and down.

The six upper and lower cylinders are disposed at six positions, i.e., the front, center, and rear left and right positions of the table 820.

Two upper and lower cylinders 831 are disposed below one end of the table 820.

The four linear shafts 841 are disposed inside the two upper and lower cylinders 831.

Two upper and lower cylinders 832 are disposed below the center of the table 820.

The two linear shafts 842 are disposed inside the two upper and lower cylinders 832.

Two upper and lower cylinders 833 are disposed at the other end of the table 820.

The two linear shafts 843 are disposed inside the two upper and lower cylinders 833.

A floating joint 835 is installed at the front ends of the upper and lower shafts.

A floating joint 835 installed at the front ends of the upper and lower cylinders connects the upper and lower shafts of the upper and lower cylinders with the roller unit.

The upper and lower plates 844 are fixed to floating joints 835 of the two upper and lower cylinders 831 and linear movement shafts 849 of the four linear shafts 841.

The upper and lower plates 844 have two bearings 862 fixed at both ends.

The upper and lower plates 845 are fixed to floating joints 835 of the two upper and lower cylinders 832 and a linearly moving shaft 849 of the two linear shafts 842.

The upper and lower plates 845 are fixed at both ends with two roller units 865.

The upper and lower plates 846 are fixed to floating joints 835 of the two upper and lower cylinders 833 and a linearly moving shaft 849 of the two linear shafts 843.

The upper and lower plates 846 are fixed with two roller units 866 at both ends.

The upper and lower plates 844 are fixed at both ends to floating joints 835 of the two upper and lower cylinders 831.

The upper and lower plates 845 are fixed at both ends to floating joints 835 of the two upper and lower cylinders 832.

The upper and lower plates 846 are fixed at both ends to floating joints 835 of the two upper and lower cylinders 833.

The upper and lower plates 846 are connected to the upper and lower cylinders via the floating joints 835, and thus there is a possibility that the upper and lower plates 846 are tilted by the elevation of the upper and lower shafts 839 of the upper and lower cylinders.

Therefore, a linear shaft is disposed on the side surface of the upper and lower cylinders, and the inclination of the upper and lower plates is suppressed by the rise of the linear moving shaft 849 of the linear shaft, so that the upper and lower plates 846 are horizontally moved in the up-down direction.

When the up-down shafts 839 of the six up-down cylinders are uniformly raised, the table 820 is horizontally raised, and when the up-down shafts 839 of the six up-down cylinders are uniformly lowered, the table 820 is horizontally lowered.

< Upper and lower guides 850>

As shown in fig. 9 (a) and (b), the off-screen mechanism 800 has an up-down guide 850 that restricts the left-right inclination of the jig 400.

The up-down guide 850 is disposed at a position closer to the rear of the table 820 and closer to the center than the up-down cylinder 833, and is disposed at the center in the width direction of the table 820.

The up-down guide 850 is a guide that prevents at least either or both of movement of the table 820 to the left and right and inclination to the left and right when the table 820 moves up and down.

The upper and lower guides 850 have a plate 851 and a cam follower 852.

The plate 851 is fixed to the stage 820 and extends vertically downward from the lower surface of the stage 820.

A plurality of cam followers 852 are mounted to the plate 851.

The plurality of cam followers 852 are arranged along the plumb direction.

The upper and lower guides 850 have guide posts 854 and guide portions 853.

The guide posts 854 are posts that are fixed to the floor of the base 510 of the housing 500 and extend vertically upward from the floor surface.

The guide portion 853 is a vertical guide that is present on one side surface of the guide post 854 in the vertical direction and sandwiches the cam follower 852.

The guide portion 853 permits the vertical and front-rear movement of the cam follower 852, but prohibits the horizontal movement.

The movement and inclination of the jig 400 to the left and right are inhibited by the guide portion 853.

< adjustment mechanism 870>

Fig. 9(c) shows an adjustment mechanism 870.

The up-down mechanism 830 includes an adjustment mechanism 870 for adjusting the height of the up-down cylinder.

The adjusting mechanism 870 has a link plate 871, a screw 872, and an indicator 873.

The linking plate 871, the screw 872, and the dial gauge 873 are disposed at three positions in front, middle, and rear of the table 820.

The coupling plate 871 is located under the floor of the base 510 and couples the lower ends of the linear motion shafts 849 located on the left and right linear axes.

Screw 872 is attached to base 510 through the floor of base 510.

The screw 872 is attached to the center of the straight shaft on the left and right.

The lower end of the screw 872 contacts the center of the web 817.

By rotating the screw 872, the vertical position of the coupling plate 871 can be changed, and the vertical position of the linear movement shaft 849 of the upper and lower cylinders in the height direction can be adjusted.

The indicating table 873 measures the height direction elevation position of the linear movement axis 849 of the upper and lower cylinders in units of 0.1 mm.

< rotating mechanism 860>

The rotation mechanism 860 is disposed above the vertical mechanism 830, and moves up and down by moving up and down the vertical mechanism 830.

The rotation mechanism 860 is a mechanism in which the stage 820 is disposed at the upper part and the stage 820 is tilted.

Rotation mechanism 860 includes shaft unit 864, roller unit 865, and roller unit 866.

The front end of the table 820 is fixed to a rotary shaft 861 of the shaft unit 864.

The center and rear end portions of the table 820 are placed on the roller unit 865 and the roller unit 866.

The shaft unit 864 is attached to the upper and lower cylinders 831 at the front end portion among the plurality of upper and lower cylinders.

The shaft unit 864 has a rotation shaft 861 and a bearing 862.

The rotation shaft 861 is fixed to the table 820 at one end in front of the table 820, horizontally.

The central axis of the rotation axis 861 is the rotation axis of the table 820.

Two bearings 862 are disposed at both left and right ends of the rotation shaft 861, and rotatably hold the rotation shaft 861.

The roller unit 865 and the roller unit 866 are mounted on the upper and lower cylinders, which are the center and the rear of the upper and lower cylinders to which the rotation shaft 861 is not mounted, among the plurality of upper and lower cylinders.

The roller unit 865 and the roller unit 866 have rollers 868 rotatable around shafts 867.

The table 820 has support plates 821 supporting rollers 868 on the right and left of the center and the rear.

When the table 820 is tilted, the roller 868 rotates around the shaft 867 on the lower surface of the support plate 821.

The roller unit 865 and the roller unit 866 are in contact with the lower surface of the table 820 only with the roller 868.

In printing, if the up-down shaft 839 of the front up-down cylinder 831 is kept raised and the up-down cylinder 833 and the up-down shaft 839 of the up-down cylinder 832 are lowered, the table 820 is tilted about the rotation axis 861. When the table 820 is inclined, the roller unit 865 and the roller 868 of the roller unit 866 rotate.

The control unit 110 changes the elevation amounts of the plurality of upper and lower cylinders on which the roller units are mounted, controls the height positions of the roller units, and tilts the table 820.

< printing section 900>

The printing unit 900 will be described with reference to fig. 12, 13, and 14.

The articulated robot 600 mounts the printing section 900 as an end effector.

The end effector is a part provided with a mechanism in which the robot directly acts on the work object.

As shown in fig. 12, the printing portion 900 has a squeegee 910 and a blade 920.

The squeegee 910 is held by the squeegee unit 930 in an exchangeable manner through the mounting portion 941.

The scraper 920 is held by the squeegee unit 930 in a replaceable manner by the mounting portion 942.

The squeegee 910 applies pressure to the screen 300 to push ink at the screen 300 against the workpiece.

The doctor blade 920 applies pressure to the screen 300 to uniformly apply the ink at the screen 300 to the screen 300.

The squeegee unit 930 is detachably attached to the tip 680.

The mounting portion 941 of the squeegee unit 930 can change a mounting angle of the squeegee 910 to mount the squeegee 910.

In fig. 12, a squeegee 910 is illustrated at three mounting angles.

Accordingly, the angle of attack of the squeegee 910 with respect to the workpiece 200 can be changed without any change to the articulated robot 600 and the robot controller 130.

Although not shown, the blade 920 may be attached to the attaching portion 942 of the blade 920 of the squeegee unit 930 by changing the attaching angle of the blade 920.

The squeegee unit 930 mounts the squeegee 910 and the scraper 920 directly below the shaft J6 or slightly rearward of the shaft J6.

The squeegee unit 930 has a presser 931 and a presser 932.

The pressurizer 931 is a pressurizer for applying a printing pressure to the squeegee 910, and may be an actuator driven to extend and contract by oil pressure, air pressure, water pressure, or electric power, and is preferably an air cylinder.

The presser 932 is a presser that applies coating pressure to the blade 920, and may be an actuator that is driven to extend and contract by oil pressure, air pressure, water pressure, or electric power, and is preferably an air cylinder.

The presser 931 and the presser 932 are fixed to both surfaces of the fixing plate 933.

As shown in fig. 13, the presser 931 has a pressing shaft 943, and the squeegee 910 is attached via a floating joint 939.

The axis JS of the pressing shaft 943 of the presser 931 is parallel to the shaft J6.

A pair of linear bushings 938 for ensuring the linear movement of the squeegee 910 are disposed on both sides of the presser 931.

A pair of linear bushings 938 are fixed to the stationary plate 933.

The linear bush 938 has a linear movement shaft 940 that linearly moves, and a lower end of the linear movement shaft 940 is fixed to a mounting portion 941 of the squeegee 910.

As shown in fig. 14, the presser 932 has a pressing shaft 943, and the blade 920 is attached via a floating joint 939.

The axis JS of the pressing shaft 943 of the presser 932 is parallel to the shaft J6.

A pair of linear bushings 938 for ensuring the linear movement of the scraper 920 are disposed on both sides of the presser 932.

A pair of linear bushings 938 are fixed to the stationary plate 933.

The linear bush 938 has a linear moving shaft 940 that linearly moves, and a lower end of the linear moving shaft 940 is fixed to a mounting portion 942 of the scraper 920.

The fixing plate 933 is fixed to the lower surface of the lower plate 934.

The lower plate 934 is sandwiched by two side plates 935.

Two side plates 935 are secured to the lower surface of the upper plate 936.

The attaching/detaching portion 937 is located on the upper surface of the upper plate 936.

The upper plate 936 has two ends that protrude like wings from the two side plates 935.

When the squeegee unit 930 is held by the suspension portion 561 of the frame 560, both ends of the upper plate 936 serve as hook portions for the suspension portion 561.

The detachable portion 937 is detachably attached to the end 680.

One lower plate 934, two side plates 935, and one upper plate 936 form a rectangular parallelepiped space S.

The pressurizer 931 and the pressurizing shaft 943 of the pressurizer 932 are disposed in the rectangular parallelepiped space S at their upper portions.

In the case where the pressing shafts 943 of the presser 931 and the presser 932 are uppermost, the head of the pressing shaft 943 does not contact the upper plate 936 either.

The rectangular parallelepiped space S is a space for ensuring free vertical movement of the pressurizing shaft 943.

Since the rectangular parallelepiped space S exists, the head of the cylinder shaft does not contact the forearm 660 of the articulated robot 600 regardless of the posture of the squeegee unit 930 by the shaft J5 of the articulated robot 600.

< < Camera 690>

As shown in fig. 12, the screen printing apparatus 100 has a camera 690.

A camera 690 is secured to the tip 680.

A camera 690 is disposed at the end 680 and at the side of the squeegee unit 930.

The camera axis JC of the camera 690 is the central axis of the lens, and is parallel to the axis J6.

The camera 690 is disposed at a position not to interfere with the disposition of the squeegee unit 930.

The camera 690 is disposed at a position not to interfere with attachment and detachment of the squeegee unit 930.

The camera 690 is disposed at a position where it does not contact the forearm 660 during printing.

A specific example of the camera 690 is a CCD camera with 500 ten thousand pixels per image.

The field of view size of the camera was 40mm across and with each pixel having a length of 19.5 microns.

< workpiece 200>

The workpiece 200 is illustrated by fig. 15.

The workpiece 200 is a curved workpiece having a curved surface with concavity and convexity in the height direction.

The workpiece 200 has no irregularities in the left-right direction and is linear.

As shown in fig. 15 (a), the workpiece 200 is a curved plate or a corrugated plate having a constant thickness in a front view.

As shown in fig. 15(c), the workpiece 200 is rectangular in a top view.

Specific examples of the material of the work 200 are glass, resin, plastic, paper, cloth, and metal.

The work 200 is a thin plate, and is flexible, easily deformed, and easily broken.

The curved surface of the workpiece 200 has at least either one of a concave surface recessed from a horizontal plane and a convex surface protruding from the horizontal plane.

The cross-sectional shape of the workpiece 200 in the left-right direction is rectangular.

The cross-sectional shape of the front-rear direction of the surface of the workpiece 200 is a wave shape.

In fig. 15, the workpiece 200 has a convex curved surface and a concave curved surface on the surface.

In fig. 15, the radius of the convex curved surface and the radius of the concave curved surface are the same length, and an example of the length of the radius is 500 mm.

The central angle of the convex curved surface and the central angle of the concave curved surface are the same angle, and are 20 degrees to 40 degrees, preferably 30 degrees.

In the center of a convex curve, there is a top 220 with the highest height.

In the center of a concave curve, there is a bottom 230 with the lowest height.

The convex and concave curved surfaces are connected by an inflection point 240.

In fig. 15, an inflection point 240 exists at the center of the workpiece 200.

The workpiece 200 has a curved surface on the back surface.

The curved surface of the back surface of the workpiece 200 corresponds to the curved surface of the workpiece 200, and has the same convex curved surface and concave curved surface as the surface of the workpiece 200.

The workpiece 200 is a curved plate of a certain thickness.

As shown in fig. 15(c), a plurality of printed lines 201 are printed as a print pattern on the workpiece 200.

Fig. 15(c) shows a case where the printed line 201 having the width V1 and the width V2 is printed on the outer periphery of the workpiece 200, and the printed line 201 having the width V1 is printed on the center.

The straight lines forming the two outer sides of the printed line 201 are referred to as outer profiles. The line in the middle of the two outer contours is referred to as the centerline 204.

As shown in fig. 15(c), the distance between the outer contour 202 and the outer contour 213 is a length V3.

Outer profile 203 is spaced from outer profile 212 by a length V4.

The distance between centerline 204 and centerline 214 is length V5.

Information of the plurality of printed lines 201 forming the print pattern, i.e., width V1, width V2, length V3, length V4, length V5, and other information are stored in the storage device for checking the print result.

< < Screen mesh 300>

The screen 300 is illustrated by fig. 15.

The screen 300 is a curved screen having a curved surface with concavity and convexity in the height direction.

The screen 300 has no unevenness in the left-right direction and is linear.

The screen 300 is rectangular in plan view.

The screen 300 is a metal mask screen, a mesh screen, or other type of screen.

The screen 300 has at least either one of a concave surface recessed from a horizontal plane and a convex surface protruding from the horizontal plane.

The curved surface of the screen 300 has a concave surface recessed from the horizontal plane and a convex surface and a curved surface protruding from the horizontal plane corresponding to the curved surface of the workpiece 200.

The cross-sectional shape of the surface of the screen 300 in the left-right direction is a straight line.

The cross-sectional shape of the surface of the screen 300 in the front-rear direction is a wave shape.

The screen 300 has a convex curved surface and a concave curved surface corresponding to the workpiece 200 shown in fig. 15.

In the center of a convex curve, there is a top 320 of highest height.

In the center of a concave curve, there is a bottom 330 with the lowest height.

The convex and concave curved surfaces are connected by an inflection point 340.

In fig. 15, an inflection point 340 exists at the center of the screen 300.

< < layout 310 >)

The chase 310 is illustrated by fig. 15.

The chase 310 is a rectangular metal frame in the shape of a picture frame.

The chase 310 is a rectangular chase having a rectangular shape and a rectangular opening at the center.

The chase 310 is a frame fixed to the chase fixing portion 760.

The chase 310 applies tension to the screen 300, holding the screen 300.

The chase 310 can be installed in a back-and-forth reversed manner with respect to the plate moving mechanism 700.

In fig. 1, the concave surface of the chase 310 is on the right side of the paper, and the convex surface is on the left side of the paper, showing the case where printing is performed in order from concave to convex.

Conversely, the plate frame 310 may be printed in order from convex to concave, with the convex side on the right side of the paper and the concave side on the left side of the paper.

< jig 400>

The fixture 400 is illustrated by fig. 15.

The jig 400 is a curved jig for holding the workpiece 200 with a curved surface.

As shown in fig. 15 (a), the jig 400 is a metal member whose lower surface is a flat surface and whose upper surface is a wavy surface in a front view.

As shown in fig. 15 (b), the jig 400 is rectangular in a plan view.

The jig 400 has a mounting surface on the upper surface, which has the same curved surface or curved surface as the workpiece 200.

Specific examples of the material of the jig 400 are resin, aluminum, iron, stainless steel, and other metals.

The jig 400 is a thick plate and thus has rigidity without deformation and breakage.

The mounting surface of the jig 400 has at least either a concave surface recessed from the horizontal plane or a convex surface protruding from the horizontal plane, corresponding to the curved surface of the back surface of the workpiece 200.

The mounting surface of the jig 400 has a convex curved surface and a concave curved surface corresponding to the workpiece 200 shown in fig. 15.

The fixture 400 can be installed back and forth opposite relative to the table 820.

In fig. 1, the concave surface of the jig 400 is on the right side of the paper, and the convex surface is on the left side of the paper, and printing is performed in order from the concave surface to the convex surface.

Conversely, the convex surface of the jig 400 may be on the right side of the paper surface and the concave surface may be on the left side of the paper surface, and printing may be performed in order from the convex surface to the concave surface.

< fiducial marking 410>

As shown in fig. 15 (b), the jig 400 has a plurality of fiducial marks 410 on the upper surface.

A specific example of the fiducial marker 410 is a circular hole with a diameter of 3 mm.

The center axis of the hole is parallel to the height direction and is present in the vertical direction.

The fiducial mark 410 can be formed at the time of manufacture of the jig 400.

The arrangement position of the reference mark 410 of the jig 400 is determined in advance based on the print pattern.

The arrangement position is a coordinate position of an orthogonal coordinate of the two-dimensional horizontal plane.

If the arrangement position of the reference mark 410 is set as the center position of the reference mark 410, the center position of the reference mark 410 can be represented by orthogonal X-axis and Y-axis values.

Specifically, the center position of the fiducial mark P1 and the center position of the fiducial mark P2 can be expressed as follows:

P1 (x1、y1)

P2 (x2、y2)。

the distance W between the center position of the fiducial mark P1 and the center position of the fiducial mark P2 can be calculated by the following equation:

W×W＝(x2－x1)×(x2－x1)＋(y2－y1)×(y2－y1)。

as described above, since the arrangement positions of all the reference marks 410 are determined in advance, the distances between all the reference marks can be determined in advance.

In fig. 15 (b), the jig 400 has 28 fiducial marks 410.

Among the 28 fiducial marks 410, 12 fiducial marks 410 are formed at the outer side of the workpiece 200.

Among the 28 fiducial marks 410, 16 fiducial marks 410 are formed at the inner side of the workpiece 200.

The two fiducial marks 410 formed on both sides of the printing line 201 where the printing pattern is formed are referred to as a pair of fiducial marks 410.

In fig. 15 (b), the jig 400 has 14 pairs of reference marks 410.

The 14 pairs of reference marks 410 are formed near the intersection where the printed line 201 and the printed line 201 intersect.

The pair of reference marks 410 are formed at positions where a straight line connecting the centers of the pair of reference marks 410 is orthogonal to the printing line 201.

The pair of reference marks 410 are formed such that the printed line 201 is positioned at the center of the pair of reference marks 410 when the printing is performed correctly.

The length W1 of the straight line connecting the centers of the pair of fiducial marks 410 is larger than the width of the printed line 201.

In fig. 15 (b), all the lengths of the straight lines connecting the centers of the 14 pairs of reference marks 410 are the same length W1.

The length W1 is larger than the maximum width of all of the printed lines 201 and smaller than the camera's field of view size of 40 mm.

In fig. 15 (b), "width V1 < width V2 < length W1 < field of view size 40 mm".

In the jig 400, the center positions of all the fiducial markers 410 are known, and the distances from the center positions of all the fiducial markers 410 to each other are known.

The distances of the center positions of all the fiducial markers 410 and the center positions of the fiducial markers 410 from each other are stored in the storage device.

The arrangement position of the ink receiving tray 570 will be described with reference to fig. 16, 17, and 18.

The frame 500 has a shelf 560 and an ink receiving tray 570.

The frame 560 is a table fixed to the base 510.

The bracket 560 is provided outside the sliding mechanism 730 near the shaft J1 among the two sliding mechanisms 730.

The frame 560 has four legs, and has a space in the center for holding the printing unit 900.

As shown in fig. 18, the frame 560 has a suspension portion 561 suspending the printing portion 900 above the four legs.

The suspension portion 561 detachably fixes both ends of the upper plate 936 of the squeegee unit 930 to hold the squeegee unit 930.

The camera 690 is always fixed to the articulated robot 600, and thus the suspension portion 561 does not have a function of holding the camera 690.

The suspension portion 561 has a space R in the center in which the printing portion 900 and the camera 690 are disposed.

The suspension portion 561 mounts and detaches the printing portion 900 to and from the articulated robot 600 in a state where the printing portion 900 and the camera 690 are arranged in the space R.

The ink receiving tray 570 projects like a brim from the side surface of the upper portion of the frame 560.

The ink receiving tray 570 is a member that receives ink that falls from the printing unit 900 while the printing unit 900 is moving.

The ink receiving tray 570 is higher than the slide mechanism 730.

The ink receiving tray 570 horizontally protrudes from one side surface of the suspension portion 561 of the frame 560.

The ink receiving tray 570 covers the slide mechanism 730 and the frame fixing portion 760.

The end of the ink receiving pan 570 is above the screen 300 of the chase 310.

< arrangement >

The arrangement of the respective portions on the plane of the screen printing apparatus 100 is explained by referring to fig. 5.

The planar shape of the screen printing apparatus 100 is a rectangle having long sides and short sides.

The two slide mechanisms 730 of the plate moving mechanism 700 are arranged in parallel with the short sides of the screen printing apparatus 100.

The short side of the chase 310 is arranged in parallel with the short side of the screen printing apparatus 100.

The long side of the frame 310 is arranged parallel to the long side of the screen printing apparatus 100.

The chase 310 slides in parallel with the short side of the screen printing apparatus 100.

The sliding mechanism 730 has a length twice as long as the short side of the chase 310.

By the sliding of the chase 310, the chase 310 is brought into a printable state covering the upper space of the jig 400 and the workpiece 200, and an inspectable state opening the upper space of the jig 400 and the workpiece 200.

The short side of the off-screen mechanism 800 is arranged in parallel with the short side of the screen printing apparatus 100.

The long side of the off-screen mechanism 800 is arranged parallel to the long side of the screen printing apparatus 100.

The jig 400 is disposed inside the disposition range of the off-grid mechanism 800.

The two circular arcs shown in fig. 5 illustrate the range of rotation of the articulated robot 600 centered on the axis J1.

The inner arc shows the maximum movable range of the axis J6 when the axis J6 is disposed in the vertical direction.

The outer arc shows the maximum movable range of the tip of the squeegee unit 930.

In fig. 5, the meanings of the symbols and the sizes are as follows.

X1: length of long side of frame 500

X2: the length of the long side of the screen 300

X3: distance from axis J1 to end SE of frame 500

X4: the distance from the straight line S0 connecting the centers of the two long sides of the housing 500 to the end SE of the housing 500, i.e., X1 ÷ 2 ═ X4

X5: distance from center position S4 of printing stroke to end SE of frame 500

X6: the length from the printing start position S1 to the printing end position S2, i.e., the length of the printing stroke

X7: distance between straight line S0 connecting centers of two long sides of frame 500 and printing start position S1 in plan view

X8: distance between straight line S0 connecting centers of two long sides of frame 500 and printing end position S2 in plan view

X9: a distance between a straight line S0 connecting the centers of the two long sides of the frame 500 and a plan view of the center position S4 of the printing stroke

Y1: length of short side of frame 500

Y2: the length of the short side of the screen 300

NP: the central angle of the range where the shaft J1 cannot rotate is about 20 degrees.

The rotatable range of the shaft J1 is 340 degrees.

The shaft J1 can rotate 170 degrees clockwise from the center of the rotatable range and 170 degrees counterclockwise.

The axis J1 is located above a straight line connecting the centers of the two end edges of the screen 300.

The axis J1 is arranged in the vertical direction.

The shaft J1 does not rotate during printing.

The axis J1 is orthogonal to the direction of the print stroke, i.e., the print direction.

The center of the rotatable range of the axis J1 and the printing direction are the same direction.

The axis J2 is arranged parallel to the short side of the housing 500 during printing and is orthogonal to the printing direction.

The position of the axis J2 in plan view is not moved during printing, and is the same as the straight line S0 connecting the centers of the two long sides of the housing 500.

The distance X7 is the same as the distance between the axis J2 and the print start position S1 in the top view.

The distance X8 is the same as the distance between the axis J2 and the printing end position S2 in the top view.

The ratio of the distance X7 to the distance X8 is one to three.

Distance X9 is the same as distance X7.

The distance X6, distance X7, distance X8, and distance X9 are in the following relationship:

X7＝X9＝X8÷2

X6＝X7＋X8＋X9。

the top view position of the shaft J2 is at a position one-quarter of the print stroke length X6 from the print start position S1.

Thus, in printing, the squeegee unit 930 is up to one quarter behind the axis J2 and three quarters behind it in front of the axis J2, within the length X6 of the printing stroke.

The top view position of the axis J2 may be within the range of the print stroke, preferably in the first half of the print stroke, and more preferably in the center of the first half of the print stroke.

The print start position S1 is directly or substantially directly below the axis J1.

The printing end position S2 is within 70% of the radius of the maximum movable range of the shaft J6.

Thus, the length X6 of the printing stroke is within 70% of the radial length of the maximum movable range of the shaft J6.

A center line connecting the centers of the short sides of the screen 300, that is, a center line of the printing width intersects the axis J1 and is orthogonal to the axis J1.

The carrier 560 is within the maximum movable range of the axis J6.

The distance from the shaft J1 to the printing end position S2 is substantially equal to the distance from the shaft J1 to the center of the suspension table of the frame 560.

Alternatively, the distance from the shaft J1 to the short side of the chase 310 where the printing end position S2 is located is substantially equal to the distance from the shaft J1 to the center of the suspension table of the frame 560.

The holder 560 for holding the squeegee unit 930 is disposed at a position where the squeegee unit 930 at the printing end position S2 is rotated clockwise by G degrees about the axis J1.

In fig. 5, the G degree is 140 degrees.

The base 610 of the articulated robot 600 is disposed at the center of the short side of the chase 310, and is offset to the side where the rack 560 is present from the center of the long side of the chase 310.

The distance from the axis J1 of the base 610 to the slide mechanism 730 farther from the axis J1 among the two slide mechanisms 730 is the same as the distance from the axis J1 to the farthest corner of the rack 560. This distance is equal to three-quarters of the maximum movable range of the articulated robot 600 having the axis J1 as the center.

The arrangement relationship and the dimensional relationship described based on fig. 5 are examples, and there are cases where the workpiece size is changed and cases where the arrangement relationship and the dimensional relationship described above are changed.

In the case of changing the workpiece size, it is desirable to arrange the center position S4 of the printing stroke at the center of the length X2 of the long side of the screen 300 so as to maintain the above-described arrangement relationship and dimensional relationship as much as possible.

The ratio shown based on the configuration relationship and the dimensional relationship explained in fig. 5 is desirably used within a range of plus or minus 20%, more desirably within a range of plus or minus 10% of the aforementioned ratio value, if possible.

Description of actions

A screen printing method of the screen printing apparatus 100 will be described with reference to fig. 19.

The following operations are performed based on the electric signal from the control unit 110.

When the articulated robot 600 is operated, the control unit 110 controls the articulated robot 600 via the robot controller 130.

The control unit 110 performs image processing by the image processing unit 140 when performing image processing in the inspection process.

When the cylinder or the pressurizer is operated, the controller 110 controls the cylinder or the pressurizer via the vacuum pump 150 and the air pressure circuit 160.

When the jig 400 is caused to suck the workpiece 200, the control unit 110 causes the jig 400 to suck the workpiece 200 via the vacuum pump 150 and the air pressure circuit 160.

The work 200 is a transparent glass plate, a transparent resin plate, or a plate having light transmittance.

A case will be described where the workpiece 200, the screen 300, and the jig 400 have a convex curved surface and a concave curved surface, and the printing portion 900 prints from the convex curved surface toward the concave curved surface.

Before the power is turned on, the squeegee unit 930 is placed in the frame 560.

The distances between the positions of all the fiducial markers 410 and the center positions of all the fiducial markers 410 are stored in a storage device.

The case of no test printing is explained below.

Power supply starting process S11

If the power of the screen printing apparatus 100 is turned on, the screen printing apparatus 100 starts an initial operation and performs initial setting in the following order.

1. Origin reset of articulated robot 600

The control unit 110 resets the articulated robot 600 to the origin.

The origin of the articulated robot 600 is a state in which the distal end 680 of the articulated robot 600 is located above the frame 560.

2. Origin reset of off-grid mechanism 800

The control unit 110 lowers the off-grid mechanism 800 to the origin.

The origin of the off-grid mechanism 800 refers to the lowest position.

Fig. 20 shows the off-grid mechanism 800 in the home position.

3. Origin reset of plate moving mechanism 700

The control unit 110 resets the plate moving mechanism 700 to the origin.

The origin of the plate moving mechanism 700 refers to the open state position.

Mounting process S12 of squeegee unit 930

The controller 110 operates the articulated robot 600 to attach the tip 680 to the squeegee unit 930 on the frame 560.

The articulated robot 600 secures the glue scraping unit 930 to the tip 680.

Transfer process S13 of workpiece 200

The control unit 110 places the workpiece 200 on the jig 400 by a loading device not shown.

That is, the workpiece 200 having the concave surface and the convex surface is placed on the jig 400 having the concave surface and the convex surface. The back surface of the workpiece 200 is overlapped with the mounting surface formed on the upper surface of the jig 400 without a gap.

The mounting surface of the jig 400 has a suction groove, and the control unit 110 sucks air in the suction groove. By this suction, the workpiece 200 is closely attached to and fixed to the mounting surface of the jig 400.

The workpiece 200 has flexibility, and even if it is conveyed in a deformed state during carrying in, it is placed on the placement surface of the jig 400 having rigidity and attracted to the placement surface, and therefore, it takes the original shape.

Setting process S14 of the chase 310 and the squeegee unit 930

The controller 110 operates the articulated robot 600 to take out the squeegee unit 930 from the rack 560 and move the squeegee unit to the upper space of the chase 310 through the upper space of the ink receiving tray 570.

The control unit 110 operates the motor 750 to slide the chase 310 from the open position to the printable position. At the same time, the control unit 110 operates the articulated robot 600 to move the squeegee unit 930 to the upper space of the workpiece 200 by the upper space of the moved chase 310.

That is, when the screen 300 is moved by the plate moving mechanism 700, the control unit 110 moves the squeegee 910 above the screen 300.

The controller 110 rotates the shaft J1 by 140 degrees to move the squeegee unit 930 from the rack 560 to the printing end position S2 of the chase 310.

Ink application process S15 based on doctor blade 920

The controller 110 operates the articulated robot 600 to apply ink to the screen 300 of the chase 310 by the doctor blade 920.

The control unit 110 moves the leading end of the scraper 920 along the curved surface of the screen 300 by the articulated robot 600.

The controller 110 moves the doctor blade 920 from the printing end position S2 to the printing start position S1 by the articulated robot 600.

The control unit 110 controls the angle of the squeegee 920 by the articulated robot 600 so that the angle of attack of the squeegee 920 with respect to the screen 300 is constant. The angle of attack of the blade 920 may be from 80 degrees to 100 degrees, preferably 90 degrees.

The control section 110 operates the presser 932 in the movement of the squeegee 920, and pushes the squeegee 920 against the screen 300. Alternatively, the control portion 110 slides the blade 920 along the surface of the screen 300 without pushing the blade 920 against the screen 300.

The control of the squeegee 920 by the articulated robot 600 is the same as the control of the squeegee 910 by the articulated robot 600 in the printing process S17 except that the moving direction is reversed, and the details of the control are described in the printing process S17.

Ascending process S16 of separating mechanism 800

The control unit 110 operates the off-screen mechanism 800 to raise the jig 400 on which the workpiece 200 is placed.

The control section 110 raises the jig 400 until the interval between the workpiece 200 and the screen 300 becomes a predetermined gap.

The clearance is set in advance within the range of 1mm to 10 mm.

Printing process S17 of articulated robot 600

The control unit 110 moves the squeegee 910 by the articulated robot 600 to print the concave surface and the convex surface of the workpiece 200.

Fig. 21 shows a printing start state.

First, the control unit 110 operates the articulated robot 600 to move the squeegee 910 to the printing start position S1.

The control part 110 moves the front end of the squeegee 910 along the curved surface of the screen 300.

That is, the articulated robot 600 moves the squeegee 910 in a wave-like manner along the curved surface of the workpiece 200 in the printing direction.

The articulated robot 600 has three axes, i.e., the axis J2, the axis J3, and the axis J5, arranged horizontally and in parallel, and moves the squeegee 910 in the printing direction by rotation of the three axes, i.e., the axis J2, the axis J3, and the axis J5.

The articulated robot 600 performs printing by arranging the remaining axes, i.e., the axis J1, the axis J4, and the axis J6, on the same vertical plane.

The same vertical plane on which the axes J1, J4, and J6 are disposed is a plane parallel to the printing direction and orthogonal to the frame 310 or the screen 300 at the center in the left-right direction of the frame 310 or the screen 300.

The control section 110 controls the angle of the squeegee 910 in such a manner that the angle of attack of the squeegee 910 with respect to the surface of the workpiece 200 is constant.

The articulated robot 600 controls the attitude of the squeegee unit 930 in such a manner that the angle of attack is constant at any position on the surface of the workpiece 200.

The angle of attack of the squeegee 910 can be from 50 to 90 degrees, preferably from 60 to 80 degrees, and more preferably 70 degrees.

The articulated robot 600 moves the squeegee unit 930 in the printing direction without applying printing pressure to the squeegee unit 930.

The control unit 110 operates the presser 931 during the movement of the squeegee 910, and pushes the squeegee 910 against the screen 300.

The reason why the printing pressure is applied only by the pressurizer 932 instead of the pressure applied by the articulated robot 600 is as follows.

Reason 1: the pressurizer 932 can maintain the printing pressure with a higher accuracy during printing than the articulated robot 600.

Reason 2: by canceling the pressure control by the articulated robot 600 and focusing the articulated robot 600 on the movement control and the angle control of the squeegee unit 930, the accuracy of the movement control and the angle control is improved.

The articulated robot 600 moves the squeegee 910 only by rotation of the horizontally and parallel axes of the articulated robot 600, that is, only by rotation of three axes of the axis J2, the axis J3, and the axis J5.

The articulated robot 600 positions the squeegee 910 at an angle of attack relative to the curved surface of the workpiece 200 and moves the squeegee 910 along the curved surface of the workpiece 200.

The articulated robot 600 does not rotate the remaining axes, i.e., the axis J1, the axis J4, and the axis J6, during printing.

The control unit 110 does not operate the off-screen mechanism 800 in the printing of the uphill slope from the printing start position S1 to the top portion 220 of the convex surface of the workpiece 200.

Rotation process of the rotation mechanism 860

The control unit 110 operates the screen separating mechanism 800 during printing, and pulls the jig 400 away from the screen 300 by the screen separating mechanism 800 after printing of the top portion 220 of the convex surface of the workpiece 200.

The control section 110 pulls the jig 400 away from the screen 300 using the rotating mechanism 860 that rotates the jig 400 relative to the screen 300.

Fig. 22 shows the operation of the off-grid mechanism 800.

As shown in fig. 23 (a), the off-screen mechanism 800 is not operated in printing, and if the jig 400 is not pulled away from the screen 300, the off-plate angle shown by the arrow decreases after printing of the top 220 of the convex surface of the workpiece 200. That is, after printing of the top 220 of the convex surface of the workpiece 200, the distance between the workpiece 200 and the screen 300 decreases.

As shown in fig. 23 (b), the control section 110 operates the off-screen mechanism 800 after the printing of the top portion 220 of the convex surface of the workpiece 200, and pulls the jig 400 away from the screen 300 to maintain the off-plate angle or the distance between the workpiece 200 and the screen 300.

The off-screen mechanism 800 increases the distance between the workpiece 200 and the screen 300 after printing on the top 220 of the convex surface of the workpiece 200 so that the distance between the workpiece 200 and the screen 300 is not reduced.

The off-screen mechanism 800 is a mechanism for ensuring the distance between the work 200 and the screen 300 at the portion printed by the squeegee 910 and the off-plate angle during printing by the squeegee 910.

The control section 110 enlarges the distance between the screen 300 on the convex surface side which has been printed and the jig 400 after the printing of the top portion 220 of the convex surface of the workpiece 200 by the rotation mechanism 860.

The control unit 110 keeps the height of the up-down shaft 839 of the up-down cylinder 831 at the end of the recess side of the workpiece 200 constant.

The controller 110 lowers the upper and lower shafts 839 of the upper and

lower cylinders

832 and 833 located at the convex-side end of the workpiece 200.

In fig. 22, control unit 110 lowers upper and lower shafts 839 of upper and

lower cylinders

832 and 833 by the same amount.

Therefore, a gap is formed between the roller 868 at the front end of the roller unit 865 on the upper and lower shafts 839 of the upper and lower cylinders 832 and the support plate 821 of the table 820.

Control unit 110 may lower upper and lower shafts 839 of upper and

lower cylinders

832 and 833 by a ratio of one to two so that no gap is formed.

By the rotation of the rotation shaft 861 of the rotation mechanism 860, the table 820 is tilted, and the jig 400 is tilted.

By lowering the jig 400 on the convex surface side, the off-plate angle can be maintained, and further, the convex portion of the workpiece 200 can be prevented from contacting the lower surface of the screen 300.

The control portion 110 brings the jig 400 into a state of being pulled away from the screen 300 during printing from the top 220 of the convex curved surface to the bottom 230 of the concave curved surface of the workpiece 200. That is, the control unit 110 sets the jig 400 to be in a state of being pulled away from the screen 300 during printing on a downward slope.

After the printing of the top portion 220 of the convex curved surface of the workpiece 200, the following control is performed as the control of the control section 110.

Control 1. before reaching the bottom 230 of the concave curve of the workpiece 200, the tilt of the jig 400 is increased, slowly pulling the jig 400 away from the screen 300.

The increase of the inclination of the jig 400 is stopped while passing the bottom 230 of the concave curved surface of the workpiece 200.

The printing after passing through the bottom 230 of the concave curved surface of the workpiece 200 maintains the inclination of the jig 400, or slowly reduces the inclination of the jig 400 and prints.

Control 2. before reaching the inflection point 240 of the convex curved surface and the concave curved surface of the workpiece 200, the inclination of the jig 400 is increased to slowly pull the jig 400 away from the screen 300.

The increase in the inclination of the jig 400 is stopped when passing the inflection point 240 of the workpiece 200.

The printing after passing the inflection point 240 of the workpiece 200 maintains the inclination of the jig 400 and prints, or slowly reduces the inclination of the jig 400 and prints.

The control part 110 brings the jig 400 close to the screen 300 until a predetermined gap is reached while gradually reducing the inclination of the jig 400.

The control portion 110 does not cause the jig 400 to approach the screen 300 until it becomes smaller than the predetermined gap.

Lowering process of up-down mechanism 830

When the rotation mechanism 860 is rotated to be sufficiently separated, the control unit 110 lowers the entire jig 400 by the vertical mechanism 830 to bring the jig 400 into a state of being separated from the screen 300.

Lowering process S18 of separating mechanism 800

When the printing is completed, the control unit 110 operates the off-screen mechanism 800 to lower the workpiece 200 and the jig 400 to the origin.

Avoiding process S19 of the chase 310 and the squeegee unit 930

The control unit 110 operates the motor 750 to move the chase 310 from the printable position to the open position.

While the chase 310 is being avoided, the control unit 110 operates the articulated robot 600 to move the squeegee unit 930 to the open position using the space above the moving chase 310.

The controller 110 rotates the shaft J1 by 140 degrees to move the squeegee unit 930 from the printing end position S2 toward the frame 560.

In the case where the ink falls from the squeegee 910 or the blade 920 in the movement of the squeegee unit 930, the ink falls to the chase 310.

The control unit 110 operates the articulated robot 600 to move the squeegee unit 930 from above the chase 310 to the rack 560 through the space above the ink receiving tray 570.

In the case where the ink falls from the squeegee 910 or the blade 920 in the movement of the squeegee unit 930, the ink falls to the ink receiving tray 570.

Separation process S20 of squeegee unit 930

The controller 110 rotates the shaft J6 so that the shaft J6 of the articulated robot 600 is perpendicular to it, and inserts the squeegee unit 930 and the camera 690 into the space R of the suspension portion 561.

The controller 110 separates the squeegee unit 930 attached to the tip 680 from the tip 680 and suspends the squeegee unit from the suspension portion 561 of the frame 560.

Inspection process S21

(photography procedure)

The controller 110 controls the plate moving mechanism 770 to move the plate frame 310 after printing and open the upper space of the workpiece 200.

The control unit 110 operates the articulated robot 600 and moves the camera 690 to the upper space of the workpiece 200 in a state where the screen 300 is moved by the plate moving mechanism 700 to open the upper space of the workpiece 200.

The control unit 110 moves the camera 690 fixed to the articulated robot 600 in a state where the squeegee 910 is detached from the articulated robot 600.

The control unit 110 positions the camera 690 over the pair of fiducial marks 410 by the articulated robot 600.

The positions where the reference marks 410 are arranged are known, and the articulated robot 600 sequentially photographs a pair of reference marks 410.

The control unit 110 positions the camera 690 with the camera axis JC of the camera 690 directed vertically downward by the articulated robot 600.

The control unit 110 operates the camera 690 to photograph one image of the pair of reference marks 410 and the printed line 201 printed between the pair of reference marks in one photographing.

The control unit 110 operates the articulated robot 600 to move the camera 690, and the camera 690 sequentially photographs all the reference marks 410 with 14. At this time, the camera shaft is always in the vertical direction. That is, the articulated robot 600 moves the camera 690 with the axis J6 in the vertical direction.

After the photographing, the control unit 110 operates the articulated robot 600 to move the camera 690 to the upper space of the frame 560.

(analysis procedure)

The control unit 110 analyzes the image photographed by the camera 690 to perform the following position check, width check, and distance check.

(position check)

The control unit 110 analyzes the image of one place photographed by the camera 690.

The control unit 110 determines whether the print pattern is good or bad based on the positions of the pair of reference marks and the position of the print pattern.

A. Example of position checking based on one reference mark

As shown in fig. 15 (d), the control unit 110 calculates a distance G1 from the center position of the reference mark P1 to the outer contour 202 of the printed line 201.

As shown in fig. 15 (d), the control unit 110 calculates a distance G3 from the center position of the reference mark P1 to the outer contour 203 of the printed line 201.

When the distance G1 and the distance G2 are predetermined distances, the control unit 110 determines that printing is normal.

The control unit 110 determines that printing is defective when the distance G1 and the distance G2 are not within the predetermined distance.

In this position check, the arrangement position of the reference mark 410 is not used. That is, the coordinates of the center position of the fiducial mark 410 are not used in the position check.

B. Position checking example 1 based on two reference marks

As shown in fig. 15 (d), the control unit 110 calculates a distance G4 from the center position of the reference mark P2 to the outer contour 203 of the printed line 201.

When the distance G1 and the distance G4 are predetermined distances, the control unit 110 determines that printing is normal.

The control unit 110 determines that printing is defective when the distance G1 and the distance G4 are not within the predetermined distance.

C. Position checking example 2 based on two reference marks

As shown in fig. 15 (d), the control unit 110 detects the outer contour 202 and the outer contour 203, and calculates the center of the outer contour 202 and the outer contour 203 as the position of the center line 204 of the printed line 201.

As shown in fig. 15 (d), the controller 110 calculates a distance K1 from the center position of the reference mark P1 to the center line 204.

As shown in fig. 15 (d), the controller 110 calculates a distance K4 from the center position of the reference mark P2 to the center line 204.

The control unit 110 determines that printing is normal when the distance K1 and the distance K4 are predetermined distances.

The control unit 110 determines that printing is defective when the distance K1 and the distance K4 are not within the predetermined distance.

When the printed line 201 must be printed at the center of the pair of reference marks, the control unit 110 further determines whether the center line 204 of the printed line 201 is at the middle position of the distance W1 between the pair of reference marks.

When K1 is K4 is W1/2, the control unit 110 determines that printing is normal.

The controller 110 determines that printing is defective when K1 is not K4 is W1/2.

That is, when the center line 204 of the printing line 201 is at the intermediate position of the distance W1 between the pair of reference marks, the control unit 110 determines that the printing at that position is normal.

When the center line 204 of the printing line 201 is offset from the middle of the two reference marks, the control unit 110 determines that the printing is defective at that position.

In this position check, the distance W1 between the pair of fiducial markers is used.

As described above, in the position inspection, the printed line and one or a pair of reference marks are photographed in one image, the distance between the printed line and the reference mark is calculated, and the quality of the printed position of the printed line is determined.

(Width inspection)

The control unit 110 determines whether the print pattern is good or bad based on the distance W1 between the pair of reference marks and the width of the print pattern.

The control section 110 calculates the width of the printing line 201 from the distance W1 of the center positions of the pair of reference marks and the image of the printing line 201.

Specifically, the control unit 110 performs the following calculation.

A. Width checking example based on one reference mark

The control unit 110 calculates "the width of the printing line 201" G3-G1 "to determine the width of the printing line 201.

The control unit 110 determines that printing is normal when the width of the printing line 201 is the predetermined width V1.

The control unit 110 determines that printing is defective when the width of the print line 201 is not the predetermined width V1.

In the width inspection, the arrangement position of the reference mark 410 is not used. That is, the coordinates of the center position of the fiducial mark 410 are not used in the position check.

B. Example of width inspection based on two reference marks

The controller 110 takes out the distance W1 between the center position of the reference mark P1 and the center position of the reference mark P2 from the storage device, and calculates the following.

The width of the printing line 201 is W1- (G1 + G4)

In the width check, the distance W1 of the pair of fiducial markers is used.

As described above, in the width inspection, the printed line and one or a pair of reference marks are photographed in one image, so that the distance between the printed line and the reference mark can be calculated, and the quality of the width of the printed line can be determined.

(distance check)

The control unit 110 analyzes images of a plurality of places photographed by the camera 690.

The control unit 110 calculates the distance between each reference mark and each printed pattern based on the position of each reference mark and the position of each printed pattern.

The control unit 110 calculates the distance between the plurality of printed patterns based on the distance between the reference mark and the printed pattern and the distance between the plurality of reference marks.

The control part 110 does not calculate the arc length of the curved surface of the workpiece 200 but calculates the linear distance of the plan view to judge whether the printing is good or bad.

In the distance check, the distance of the two reference marks and the two printing lines 201, and the distance of the two reference marks stored in the storage device are used.

In the distance inspection, the arrangement position of the reference mark 410 is not used. That is, the coordinates of the center position of the fiducial mark 410 are not used in the position check.

When the distances of the 2 reference marks are not stored in the storage device, the distance between the two reference marks may be calculated from the coordinates of the center positions of the reference marks 410.

Specifically, the control unit 110 performs the following inspection.

A. Distance checking example 1

Let W2 be the distance between the center position of the reference mark P1 and the center position of the reference mark P4 disposed on the straight line L shown in fig. 15.

The control unit 110 determines the distance G1 between the center position of the reference mark P1 and the outer contour 202 of the printed line 201 based on the position of the reference mark P1 and the position of the outer contour 202 of the printed line 201.

The control unit 110 determines the distance G2 between the center position of the reference mark P4 and the outer contour line 213 of the printed line 211 based on the position of the reference mark P4 and the position of the outer contour line 213 of the printed line 211.

The controller 110 determines that the operation is normal when the distance W2- (distance G1 + distance G2) is a predetermined length V3.

The controller 110 determines that the fault is present when the distance W2- (distance G1 + distance G2) is not longer than the predetermined length V3.

Further, the distance between the center position of the reference mark P2 and the center position of the reference mark P3 arranged on the straight line L shown in fig. 15 is W3.

The control unit 110 determines the distance G4 between the center position of the reference mark P2 and the outer contour 203 of the printed line 201 based on the position of the reference mark P2 and the position of the outer contour 203 of the printed line 201.

The control unit 110 determines the distance G5 between the center position of the reference mark P3 and the outer contour 212 of the printed line 211 based on the position of the reference mark P3 and the position of the outer contour 212 of the printed line 211.

The controller 110 determines that the operation is normal when the distance W3 + (distance G4 + distance G5) is a predetermined length V4.

The controller 110 determines that the fault is present when the distance W3 + (distance G4 + distance G5) is not longer than the predetermined length V4.

B. Distance checking example 2

The control unit 110 determines the distance K1 between the center position of the reference mark P1 and the center line 204 of the printing line 201 based on the position of the reference mark P1 and the position of the center line 204 of the printing line 201.

The control unit 110 determines the distance K2 between the center position of the reference mark P4 and the center line 214 of the printed line 211 based on the position of the reference mark P4 and the position of the center line 214 of the printed line 211.

The controller 110 determines that the operation is normal when the distance W2- (distance K1 + distance K2) is a predetermined length V5.

The controller 110 determines that the fault is present when the distance W2- (distance K1 + distance K2) is not longer than the predetermined length V5.

The control unit 110 determines the distance K4 between the center position of the reference mark P2 and the center line 204 of the printing line 201 based on the position of the reference mark P2 and the position of the center line 204 of the printing line 201.

The control unit 110 determines the distance K5 between the center position of the reference mark P3 and the center line 214 of the printed line 211 based on the position of the reference mark P3 and the position of the center line 214 of the printed line 211.

The controller 110 determines that the operation is normal when the distance W3 + (distance K4 + distance K5) is a predetermined length V5.

The controller 110 determines that the fault is present when the distance W3 + (distance K4 + distance K5) is not longer than the predetermined length V5.

As described above, in the distance inspection, two positions are imaged for the printed line and one reference mark, and thus the distance of the printed line can be calculated from the distance between the two reference marks and the distance from the reference mark to the printed line obtained from the two images.

Other inspection contents and inspection methods and calculation methods different from the aforementioned inspection contents and inspection methods and calculation methods may also be used.

In the inspection step S21, only the arrangement position of the fiducial marker 410 is used for positioning the camera 690.

In the inspection step S21, the position of the reference mark 410 is not used to determine whether the printed pattern is good or bad.

In the inspection step S21, only the distance between the reference mark 410 and the printed pattern is used, or only the distance between the reference marks 410 is used.

The control unit 110 can display the photographed image, the measured value, the calculated value, and the detection result on the monitor 120 for visual confirmation during or after photographing.

Specifically, the control unit 110 displays an image, a measurement value, a calculation value, and an inspection result on the monitor 120 in sequence or selectively based on an instruction from the dashboard 170.

Further, the control unit 110 displays an image of the print pattern determined to be defective, the measurement value, the calculation value, and the inspection result on the monitor 120 based on an instruction from the dashboard 170.

Work 200 carrying-out process S22

The control unit 110 carries out the workpiece 200 by a carrying-out device not shown.

Repeating the step S23

After the workpiece 200 is carried out, the control unit 110 determines whether or not the next printing is present, and returns to the mounting step S12 of the squeegee unit 930.

If there is no next printing, the control section 110 ends the printing.

As described above, in embodiment 1, the screen printing method having a function of printing on the work 200 having both the curved surfaces of the unevenness is described.

In addition, a screen printing method in which a printing position is measured by the camera 690 after screen printing and a printing result is checked is described.

According to the screen printing method described above, printing can be performed on a glass substrate, a film, or another curved work having a curved shape.

Description of effects of embodiment 1

According to embodiment 1, since the articulated robot 600 is provided, the workpiece 200 having a curved surface can be printed.

The advantage of using the articulated robot 600 is as follows.

A. In flexographic printing, the squeegee 910 and the scraper 920 can be moved along a curved surface.

B. In flexographic printing, the angles of attack of the squeegee 910 and the doctor blade 920 can be made constant.

C. The articulated robot 600 can perform both printing and inspection operations. That is, by making the squeegee unit 930 detachable, the inspection by the camera 690 can be performed.

D. The squeegee unit 930 can be moved to the frame 560, and the upper space of the workpiece 200 can be completely opened.

E. Instead of the carrying-in and carrying-out devices for the workpiece 200, the multi-joint robot 600 may carry in and carry out the workpiece 200.

Since the screen printing apparatus 100 includes the jig 400 having the curved surface corresponding to the curved surface of the workpiece, printing can be performed without deforming the workpiece 200.

Since the articulated robot 600 is of a suspension type, the screen printing apparatus 100 has a small planar area.

Since the articulated robot 600 performs printing by arranging three axes horizontally and arranging the remaining axes on the same plane, the squeegee unit 930 can be operated with high accuracy.

Since the articulated robot 600 performs printing by controlling only three horizontally arranged axes, the squeegee unit 930 can be accurately moved linearly in a plan view.

Since the articulated robot 600 prints by fixing all the axes other than the three horizontally arranged axes, the attitude control of the squeegee unit 930 is easy.

According to embodiment 1, since the screen having the uneven surface corresponding to the uneven surface on the surface of the workpiece 200 is provided, the workpiece 200 having a curved surface can be printed.

Since the off-screen mechanism 800 for changing the distance between the workpiece 200 and the screen 300 is provided, the off-screen angle can be optimally adjusted.

Since the off-screen mechanism 800 pulls the jig 400 away from the screen 300 after printing of the top 200 of the convex surface of the workpiece 200, a reduction in the off-plate angle of the convex surface of the workpiece 200 and the screen 300 can be avoided.

The off-screen mechanism 800 can adjust the off-plate angle of the workpiece 200 and the screen 300 by the up-down mechanism 830 that moves the jig 400 up and down and the rotation mechanism 860 that rotates the jig.

According to embodiment 1, since the jig 400 having the reference mark 410 and the camera 690 are provided, the printed pattern can be inspected.

Since the reference mark 410 is formed on the firm jig 400 instead of the workpiece 200 of the curved plate, it is possible to perform a correct inspection without positional deviation of the reference mark 410.

Since the reference mark and the print pattern are photographed in a state where the camera 690 has the camera axis directed vertically downward, photographing is easy and position calculation is easy.

Since the workpiece 200 is transparent, the camera 690 can photograph the reference mark 410 through the workpiece 200.

According to embodiment 1, since the plate moving mechanism 700 for moving the plate frame 310 is provided, the printed pattern can be inspected without moving the workpiece 200.

When the inspection is performed after the workpiece 200 is carried out from the jig 400, the inspection may be performed in a state where the workpiece 200 is deformed, and thus, a correct inspection cannot be ensured.

Since the articulated robot 600 moves the camera 690 with the squeegee unit 930 detached, ink does not fall off the squeegee 910 or the scraper 920 during inspection.

Since the camera 690 is always fixed to the articulated robot 600, the camera 690 does not need to be attached and detached.

Since the printed line and at least one reference mark are photographed in one image, the distance between the printed line and one reference mark can be calculated, and the quality of the printing position of the printed line or the quality of the width of the printed line can be determined.

That is, since the position of the reference mark is known, the quality of the position of the printed line can be known by calculating the distance between the reference mark and the printed line, and the quality of the printed pattern can be determined.

Since the printed lines and the reference marks are imaged at a plurality of positions, the distance between the printed lines can be calculated from the distance between the reference marks and the distance from the reference mark to the printed line, and the quality of the distance between the printed lines can be determined.

That is, since the positions of the two reference marks 410 are known, the distance between the two printed lines can be calculated based on the positions of the two reference marks 410 and the positions of the printed lines, and the quality of the printed pattern can be determined.

Modifications of embodiment 1

(modification of work 200)

The surface of the workpiece 200 may also have a plurality of concave curved surfaces and a plurality of convex curved surfaces.

The radius lengths of the concave curved surface and the convex curved surface of the workpiece 200 may also be different.

On the surface of the workpiece 200, there may be a concave curved surface having different radii and a portion where the concave curved surface continues.

On the surface of the workpiece 200, there may be a convex curved surface having different radii and a portion where the convex curved surface is continuous.

On the surface of the workpiece 200, there may also be a portion where curved surfaces and planes are continuous.

The back surface of the workpiece 200 does not need to have a curved surface corresponding to the surface of the workpiece 200, and the thickness of the workpiece 200 may not be constant.

The back side of the workpiece 200 may also be planar. When the back surface of the workpiece 200 is a flat surface, the jig 400 may be a flat surface corresponding to the flat surface of the back surface of the workpiece 200.

The workpiece 200 may have one or both of a concave portion and a convex portion in at least a part thereof not only in the front-back direction but also in the left-right direction. When the workpiece 200 has a concave portion or a convex portion in the left-right direction, a convex portion or a concave portion corresponding to the concave portion or the convex portion of the workpiece 200 may be present at the tip of the squeegee 910.

(modification of the holder 400)

The mounting surface of the jig 400 may not conform to the shape of the back surface of the workpiece 200, and if the workpiece 200 has sufficient hardness, a gap may exist between the mounting surface of the jig 400 and the back surface of the workpiece 200.

The fiducial mark 410 may also be present in no pair with respect to the printed line 201, and may also be present in one pair with respect to the printed line 201. In the case where there is one reference mark 410 with respect to the printed line 201, since the position of the reference mark 410 is known, the position of the reference mark 410 and the distance of the printed line 201 can also be calculated.

In addition, when there is one reference mark 410 with respect to the printing line 201, the distance of the plurality of printing lines 201 can be calculated using the distance of the plurality of reference marks 410.

The reference mark 410 may be formed not in a straight line of the printed line 201 but in correspondence with a curved, square, triangular, polygonal, semicircular, or other shape of the printed pattern.

The reference mark 410 need not be present at each end of the printed line 201, but may be present only at a portion that is considered important from the viewpoint of quality inspection.

The reference mark 410 may be not a hole, but a mark or a sticker described on the surface of the jig 400.

The fiducial marker 410 may be shaped other than a circle, and may be square, triangular, polygonal, rectilinear, semicircular, or other shape.

The fiducial mark 410 may be photographed and recognized by a camera 690.

The fiducial marks 410 can also be only on the outside of the workpiece 200.

The fiducial marks 410 can also be only on the inside of the workpiece 200.

When the reference mark 410 can be photographed by the camera 690 through the workpiece 200, the reference mark 410 may be only at a position covered by the workpiece 200. Specific examples of the case where the reference mark 410 can be photographed by the camera 690 through the workpiece 200 include a case where the workpiece 200 is transparent, and a case where the workpiece 200 has a through hole through which the reference mark 410 is exposed.

The center axis of the hole of the reference mark 410 may be perpendicular to the surface of the workpiece 200 instead of the vertical direction, to form the reference mark 410. When photographing is performed by the camera 690, the articulated robot 600 photographs the camera shaft JC and the center axis of the hole of the reference mark 410 in alignment. The control section 110 calculates the size and distance of the print pattern based on the arc length of the curved surface.

(modification of articulated robot 600)

The articulated robot 600 may be not a six-axis robot, but may be a five-axis, four-axis, or three-axis robot.

Specifically, the shaft J4 may be omitted.

The axis J1 may also be absent if there is no inspection based on the camera 690 and there is no need to move the squeegee unit 930 to the rack 560.

The axis J6 may also be absent if there is no inspection based on the camera 690 and there is no need to rotate the squeegee unit 930 over the shelf 560.

The plate moving mechanism 700 and the screen separating mechanism 800 can also be used for a screen printing apparatus using a driving mechanism that linearly moves the squeegee unit 930 in the horizontal direction.

The inspection contents and the inspection method using the reference mark described above can also be used for a screen printing apparatus using a driving mechanism that linearly moves the squeegee unit 930 in the horizontal direction.

The camera 690 may not be mounted on the articulated robot 600, and instead of mounting the camera 690 on the articulated robot 600, the camera 690 may be mounted on a two-dimensional drive mechanism that moves the camera 690 in a horizontal two-dimensional direction.

(modification of plate moving mechanism 700)

The plate moving mechanism 700 may move the chase 310 forward and backward instead of moving the chase 310 left and right.

The plate moving mechanism 700 may rotate the plate frame 310 with one side of the plate frame 310 as an axis.

Instead of moving the chase 310 to the right and left, the plate moving mechanism 700 may move the screen separating mechanism 800 by mounting the screen separating mechanism 800 on a mobile station.

(modification of off-grid mechanism 800)

If the table 820 is strong, there may be no upper and lower cylinders 832 and linear shafts 842 in the center of the off-wire mechanism 800.

The linear axes 841 in front of the off-grid mechanism 800 may also be two instead of four.

The off-grid mechanism 800 may not include both the up-down mechanism 830 and the rotation mechanism 860, or may include only the up-down mechanism 830 or only the rotation mechanism 860.

Although the rotation mechanism 860 is shown as a mechanism that tilts only to one side, the rotation mechanism 860 may tilt only to the opposite side. Alternatively, the rotation mechanism 860 may be a mechanism inclined to both sides.

The vertical guides 350 may be provided in plural on the left and right sides of the lower surface of the table 820, or in plural on the front and rear sides of the lower surface of the table 820.

(modification of printing section 900)

Although the case where the squeegee 910 and the blade 920 are present in the printing portion 900 is illustrated, either one of the squeegee 910 and the blade 820 may be mounted on the printing portion 900 instead.

The space S may not be provided in the printing portion 900 if the printing portion 900 does not contact the front arm 660 due to the rotation of the tip 680.

(variation of operation: test printing)

The test printing is different from the above-described operation.

In the loading step S13 of the workpiece 200, the workpiece 200 is placed on the jig 400.

After that, the roll film in the roll holding portion 590 is pulled out and covers the workpiece 200 with the roll film.

Thereafter, the setting process S14 to the inspection process S21 are performed with respect to the roll film.

That is, the chase 310 and the squeegee unit 930 are moved to the printing position and the roll film is printed.

After that, the printing result on the roll film was checked.

After the inspection of the printing result on the roll film is finished, the roll film is peeled off from the work 200.

If the printing result on the roll film is poor, the cause of the poor is eliminated and test printing is performed again.

If the printing result on the roll film is normal, the setting process S14 to the carrying-out process S22 are performed on the workpiece 200. That is, the chase 310 and the squeegee unit 930 are moved to the printing position and the printing and inspection are performed on the workpiece 200 and the workpiece 200 is carried out.

(variation of operation: sampling inspection)

The inspection step S21 may not be performed every time, and a sampling inspection may be performed.

When the sampling inspection is performed, the standby step of the squeegee unit 930 may be performed instead of the separation step S20, without performing the separation step S20 of the squeegee unit 930.

The standby process is a process of waiting the squeegee unit 930 above the ink receiving tray 570 in a state where the squeegee unit 930 is mounted on the articulated robot 600.

Even if the ink drops from the squeegee 910 or the doctor blade 920 during standby, the ink can be received by the ink receiving tray 570.

(variation of operation: from gravure printing to flexographic printing)

As shown in fig. 1, the workpiece 200 may also be printed first on the concave side and then on the convex side.

Fig. 24 shows the case where the workpiece 200 is printed first on the concave side and then on the convex side.

When printing the concave surface of the work 200, since there is no convex portion at the printed portion, the jig 400 does not need to be pulled away from the screen 300.

As shown in fig. 24 (a), even after the top 220 of the convex surface of the workpiece 200 is printed, if the step of the downslope is small, the printing is finished before the off-plate angle or the distance between the workpiece 200 and the screen 300 becomes small, and thus the jig 400 does not need to be pulled away from the screen 300.

After the top portion 220 of the convex surface of the workpiece 200 is printed, if the height difference of the downward slope is large, as shown in fig. 24(b), only the up-down mechanism 830 is operated to pull the entire jig 400 away from the screen 300. Alternatively, as shown in fig. 24 (c), the rotation mechanism 860 is operated to pull the rear side of the jig 400 away from the screen 300.

Although not shown, when the workpiece 200 has a wavy surface formed by a plurality of continuous irregularities, the control unit 110 adjusts the plate separation angle between the workpiece 200 and the screen 300 or the distance between the workpiece 200 and the screen 300 by using the vertical mechanism 830 and the rotation mechanism 860.

In principle, the control section 110 performs control of pulling the workpiece 200 and the screen 300 apart in downhill printing after uphill printing.

(operation modification: reverse printing)

It is also possible to reverse the printing direction.

When the printing direction is reversed, the following configuration can be considered.

Configuration 1. the arrangement of the articulated robot 600 shown in fig. 1 is reversed.

Configuration 2. the printing unit 900 is installed in reverse to the articulated robot 600 shown in fig. 1.

Configuration 3. with respect to the printing section 900 of the articulated robot 600 shown in fig. 1, the squeegee 910 and the blade 920 are reversed by 180 degrees and the mounting positions of the squeegee 910 and the blade 920 are replaced.

(modification of operation: attachment/detachment of Camera 690)

A camera holding unit for holding the camera 690 may be formed in the holder 560, and the camera 690 may be attached to and detached from the articulated robot 600. The control unit 110 holds the camera 690 in the camera holding unit during printing, and removes the squeegee unit 930 from the articulated robot 600 and attaches the camera 690 to the articulated robot 600 during inspection.

(variation of operation: pressure of printing)

In printing, the squeegee 910 may be pressed by the articulated robot 600 without using the presser 931.

Alternatively, the squeegee 910 may be pressed by the presser 931 and the articulated robot 600 during printing.

Also, in the ink application, the blade 920 may be pressed by the articulated robot 600 without using the presser 932.

Alternatively, the presser 932 and the articulated robot 600 may be used to apply pressure to the blade 920 during ink application.

Description of the symbols

100 screen printing device, 110 control part, 120 monitor, 130 robot controller, 140 image processing unit, 150 vacuum pump, 160 air pressure circuit, 170 instrument panel, 200 workpiece, 201, 211 printing line, 202, 203, 212, 213 outline, 204, 214 central line, 220 top, 230 bottom, 240 inflection point, 300 silk screen, 310 chase, 320 top, 330 bottom, 340 inflection point, 400 clamp, 410 reference mark, 500 frame body, 510 base, 520 control box, 530 column frame, 540 beam frame, 550 top plate, 560 rack, 561 suspension part, 570 ink receiving disc, 590 roller holding part, 600 multi-joint robot, 610 base, 620 main body, 630 shoulder, 640, 650 elbow, 660 forearm, 670, 680 tip, 690 camera, 690, 700 edition moving mechanism, 720 legs, 730 sliding mechanism, 740 conveying belt, 750 motor, 760 frame fixing part, 800 off-screen mechanism, 820 table, 821 support plate, 822 frame, 830 up-down mechanism, 831, 832, 833 up-down cylinder, 835 floating joint, 839 up-down shaft, 841, 842, 843 straight line shaft, 844, 845, 846 up-down plate, 849 straight line moving shaft, 850 up-down guide, 851 plate, 852 cam follower, 853 guide part, 854 guide column, 860 rotating mechanism, 861 rotating shaft, 862 bearing, 864 shaft unit, 865, 866 roller unit, 867 shaft, 868 roller, 870 adjusting mechanism, 871 connecting plate, 872 screw, 873 indicating meter, 900 printing part, 910 glue scraper, 920 scraper 930, glue scraper unit, 931 presser, 932 presser, 933 fixing plate, 934, lower plate, 935 side plates, 936 upper plates, 937 detachable parts, 938 linear shaft sleeves, 939 floating joints, 940 linear moving shafts, 941 installation parts, 942 installation parts, 943 pressurizing shafts, J1, J2, J3, J4, J5, J6 shafts, JC camera shafts, S1 printing starting positions, S2 printing ending positions, P1, P2, P3 and P4 reference marks.

Claims

1. A screen printing device for printing a work having a curved surface on a surface thereof by squeegee, comprising:

a jig on which the workpiece is placed and which has a reference mark;

a camera for photographing the reference mark of the jig and a print pattern printed on the workpiece; and

2. The screen printing apparatus according to claim 1, wherein the control portion photographs the reference mark and the print pattern with the camera in a state where a camera axis of the camera is oriented vertically downward.

3. The screen printing apparatus according to claim 1 or 2, wherein the work is transparent,

the camera photographs the fiducial mark through the workpiece.

4. The screen printing apparatus according to claim 1 or 2, wherein the screen printing apparatus comprises:

a screen having a printing pattern; and

a plate moving mechanism that moves the screen,

the control unit performs imaging with the camera in a state where the screen is moved by the plate moving mechanism to open the upper space of the workpiece.

5. The screen printing apparatus according to claim 1 or 2, wherein a multi-joint robot to which the squeegee is detachably attached and to which the camera is fixed is provided,

the control unit moves the camera in a state where the squeegee is detached from the articulated robot.

6. The screen printing apparatus according to claim 1 or 2, wherein the camera photographs one reference mark and the print pattern in one photograph,

the control unit analyzes the image photographed by the camera, and determines whether the print pattern is good or bad based on the position of the one reference mark and the position of the print pattern.

7. The screen printing apparatus according to claim 1 or 2, wherein the camera photographs a pair of the reference mark and the print pattern in one photograph,

the control unit analyzes the image photographed by the camera, and determines whether the print pattern is good or bad based on the positions of the pair of reference marks and the position of the print pattern.

8. The screen printing apparatus according to claim 1 or 2, wherein the camera photographs the reference mark and the print pattern at a plurality of places,

the control unit calculates distances between the reference marks and the print patterns, and calculates distances between the print patterns at the plurality of positions based on the calculated distances and the distances between the reference marks at the plurality of positions.

9. A screen printing method for printing a work having a curved surface on a surface thereof by squeegee, wherein,

forming a reference mark on a jig on which the workpiece is placed,

a camera photographs the reference mark of the jig and a print pattern printed on the workpiece,

the control unit analyzes the printing result from the image photographed by the camera.