JPH0489258A - Screen printer for all peripheral printing - Google Patents

Abstract

PURPOSE:To obtain all peripheral printing of a cubic work even in a general plane screen system by a method wherein a work rolling mechanism which successively rolls a peripheral surface of the cubic work closely along a rear surface of a screen is provided to a screen printer which makes ink supplied from a front surface of a plane screen permeate the rear surface as a specific image. CONSTITUTION:A side surface S1 of a work W is stuck fast to a rear surface of a screen 20. A squeegee 35 is brought into contact with a surface of the screen 20 at one end (a position P1) to be slid to the other end (a position P2) pushing, on ink., and plane printing is performed along the side surface S1. Then, for the work W, rotation around a support center shaft A, separation from the screen 20, and feed in a sliding direction of the squeegee 35 are performed in synchronization with one another from a state in which the side surface S1 sticks fast to the screen 20, and the work W is rolled to a state of sticking fast to a side surface S2. In that case, the squeegee 35 is slid from position P2 to a position P3 conforming to a part at which the rolling work W sticks fast to the screen 20, and rolling printing is carried out along a curved surface C1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a screen printing machine for all-round printing, and can be used for printing the circumference of a three-dimensional object using a flat screen printing machine.

[Background technology]

Screen printing has traditionally been applied to printing on materials and articles other than paper, taking advantage of the uniqueness of the stencil method that performs transparent printing.

In screen printing, a mesh screen made of silk cloth or stainless steel wire mesh is stretched over a frame, and a thin film (
A printing plate is created by making holes in the stencil according to the desired image, then applying ink over the plate and leveling it with a linear press (squeegee).The ink that has passed through the holes is applied to the printing material on the back side to form the desired printed image.

Screen printing machines have been developed to automatically perform such screen printing. In screen printing machines, it is common to hold the screen exclusively on a flat frame.

[Invention or problem to be solved]

By the way, with the increase in plastic containers in recent years,
There is a demand for surface printing, especially all-around printing, of three-dimensional printing objects (workpieces) using screen printing.

However, cylindrical containers and cylindrical containers with rounded corners and polygonal cross sections have curved parts, making it difficult to print with a typical flat screen printing machine as it is difficult to achieve close contact with the screen. .

On the other hand, it is possible to dedicate a screen printing machine and make the screen holding frame curved to match the workpiece, but this would reduce the versatility of the machine and avoid problems such as complicating replacement work depending on the workpiece. There was a problem with not being able to do it.

SUMMARY OF THE INVENTION An object of the present invention is to provide a screen printing machine for all-round printing that is capable of printing a three-dimensional workpiece all around, although it uses a general flat screen method.

[Means for Solving the Problems] In the present invention, a screen printing machine that transmits ink supplied from the front surface of a planar screen to the back surface as a predetermined image is provided with a peripheral surface of a three-dimensional workpiece on the back surface of the screen. A work rolling mechanism is provided to sequentially roll the parts in close contact.

Here, the workpiece rolling mechanism includes a rotating holding means that rotates the held workpiece around a rotational axis along the screen, and a rotational holding means that rotates the held workpiece around the rotational axis along the screen, and a rotating holding means that rotates the workpiece across the rotational axis according to the circumferential speed of the workpiece at a position facing the screen. It is desirable to provide a parallel moving means for moving the workpiece in a direction parallel to the screen to realize rolling of the workpiece against the back surface of the screen.

In addition, a proximity separating means is provided for separating the workpiece close to the screen so that the peripheral surface of the workpiece at a position facing the screen is in close contact with the screen, and the adhesion of the workpiece to the back surface of the screen is ensured regardless of the cross-sectional shape of the workpiece. or desirable.

The above-mentioned three-dimensional work may be cylindrical, prismatic, or cylindrical with a polygonal cross section with rounded corners, and may be linear in the circumferential or axial direction.

[For production]

In the present invention, the circumferential surface of the three-dimensional workpiece is successively rolled in close contact with the back surface of the planar screen by the workpiece rolling mechanism. For this reason, the squeegee is slid on each part of the workpiece that is currently in close contact with the workpiece to print on that part, and the workpiece is sequentially rolled to continue printing on the previous parts, thereby printing all around the workpiece. or will be done. This allows full-circle printing of three-dimensional workpieces by means of a flat screen printing machine, thus achieving the above-mentioned objective.

〔Example〕

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

1 and 2, the screen printing machine 10 for all-round printing of this embodiment includes a screen 20 and a printing mechanism 3 for performing flat screen printing on an upper case 11.
0, and a work rolling mechanism 610 that holds a three-dimensional work W on the central table 12 and rolls it closely against the back surface of the screen 20.

A pair of holding members 21 are fixed to the front surface of the upper case 11, and a rectangular frame 23 is removably supported on the holding members 21 by tightening screws 22. The inside of the frame 23 is covered with silk cloth, stainless wire mesh, etc., and a predetermined image or cut stainless steel (not shown) is pasted on its surface. A planar screen 20 is formed by these.

A skein carrier 31 is installed on the upper surface of the upper case 11. The base end of the carrier 31 is the kite slit 3
2 and is screwed onto a feed screw shaft (not shown) installed inside the case 11, and is sent in the longitudinal direction of the screen 20 by rotating the feed screw shaft with a drive motor 33 on the side. An ink return plate 34 is provided on the lower surface of the tip side of the carrier 31 and slides over the entire width of the surface of the screen 20.
and a squeegee 35 are installed, each of which is connected to the upper and lower cylinders 3.
6.37 makes contact and separation with respect to the screen 20. Therefore, by sending the carrier 31 in contact with the squeegee 35 or the like, ink is spread evenly over the entire surface of the screen 20, and transparent printing is performed on the back side of the screen 20. These constitute a printing mechanism 30.

A lifting table 41, a moving table 42, and a work holder 43 are installed as a work rolling mechanism 40 on the central table 12, and a work W is held on this work holder 43.

The lifting table 41 is connected to the lower motor panel 5 via a pair of guide rods 51 that slide through the center table 12.
It is connected to 2. The drive motor 5 is mounted on the motor board 52.
3 is installed, and the drive motor 53 is connected to a feed screw shaft 54 whose intermediate portion is screwed to the central table 12. Therefore, the lifting table 41 is raised and lowered by the operation of the drive motor 53, and the workpiece W is moved close to and away from the screen 20. These constitute the proximity/separation means 50.

The moving table 42 has a pair of guide rails 6 installed on the top surface of the lifting table 41 in the longitudinal direction of the screen 20.
1 is guided and supported. A drive motor 62 is installed at the end of the lifting table 41, and the drive motor 62 has a feed screw shaft 63 screwed into the lower surface of the moving table 42 at the middle.
is connected. Therefore, the moving table 42 is moved horizontally by the operation of the drive motor 62, and is moved parallel to the workpiece W screen 20. These constitute a parallel movement means 60.

The work holder 43 has a substrate 72 that is locked on the top surface of the moving table 42 by a pair of locking members 71, and has a substrate 72 on the front side and the back side of the substrate 72 that is parallel to the screen 20 and on the axis in the width direction. Contact members 73 and 74 are arranged coaxially and oppositely. The abutting member 73 on the near side is rotatably connected to a clamp cylinder 75, and is moved forward and backward toward the abutting member 74 by the cylinder 75. A drive motor 76 is connected to the abutting member 74 on the back side, and is rotationally driven by the motor 76. Therefore, the work holder 43 can hold the work W by placing the work W between the contact members 73 and 74 and operating the clamp cylinder 75. In this state, by operating the drive motor 76, the work W can be held between the contact members 73 and 74. W to contact member 73
．． It is possible to rotate it together with 74. These constitute the rotation holding means 70.

As shown in FIG. 3, the drive motor 33 of the aforementioned printing mechanism 30, the drive motor 53°62 of the work rolling mechanism 40,
76 is connected to control means 80.

The control means 80 includes a printing control section 81 and a rolling control section 82.
It is equipped with Among these, the print control section 81 is activated by an external command to control the operation of the printing mechanism 30, and causes the drive motor 33 to perform the feeding operation of the squeegee 35. On the other hand, the rolling control section 82 controls the operation of the workpiece rolling mechanism 40 based on the feeding position data from the printing control section 81.
A workpiece W that comes into close contact with the back side of the screen 20 as necessary
roll. For this purpose, the rolling control section 82 controls the operation of each motor 53, 62, 76 of the workpiece rolling mechanism 40 with the lifting control section 83. Horizontal feed control section 84, rotation control section 8
5, a cross-sectional shape data storage section 86 in which the cross-sectional shape of the workpiece W to be used is set, and a cooperative calculation section 87 that calculates the amount of operation of each motor 53, 62, and 76 necessary for rolling the workpiece W. ing. Here, the cooperative calculation unit 87 refers to the cross-sectional shape data in the storage unit 86 based on the feed position data from the print control unit 81, and determines whether the contact area of the workpiece W with the screen 20 at that point is a flat surface. However, in the case of a curved surface, the shaft center lift amount, shaft center horizontal feed amount, and rotation angle around the shaft are calculated from the curvature of the part, the distance from the center axis, etc., and each is controlled by the corresponding lift control section 83. It is configured to output to a horizontal feed control section 84 and a rotation control section 85.

Next, specific operations in this embodiment will be explained based on FIG. 4.

Here, it is assumed that the workpiece W used for printing is a cylindrical body having a rectangular cross-sectional shape with rounded corners. In such a case, the circumferential surface of the workpiece W has four side surfaces 5l-34 and a curved surface C at each corner.
1 to C4 are consecutive. Therefore, normal planar screen printing with the workpiece W fixed is performed on each of the side surfaces 81 to S4, and screen printing is performed on each of the curved surfaces c1 to C4 while the workpiece W is rolling.

First, the side surface Sl of the workpiece W is brought into close contact with the back surface of the screen 20, and the squeegee 35 is brought into contact with the surface of the screen 20 at one end (position Pi), and the ink is pressed down and slid to the other end (position P2). Planar printing is performed on the side surface S1.

Next, from the state in which the workpiece W is in close contact with the side surface S1 or the screen 20, rotation around the holding center axis A, separation from the screen 20, and feeding in the sliding direction of the squeegee 35 are performed in synchronization, and the workpiece W is brought into close contact with the side surface S2. Roll it until it reaches the desired state. At this time, the squeegee 35 is slid from position P2 to position P3 in accordance with the area where the rolling workpiece W and the screen 20 come into close contact, and rolling printing is performed on the curved surface C1.

Further, in the same manner as on the side surface S1, the squeegee 35 is slid from the position P3 to the position P4 while the workpiece W remains in close contact with the screen 20 on the side surface S2 to perform flat printing on the side surface S2.

Subsequently, similarly to the curved surface C1, rotation around the holding center axis A,
The approach to the screen 20 and the feeding of the squeegee 35 in the sliding direction are synchronized to prevent the workpiece W from rolling.
5 from the position P4 to the position P5 to perform rolling printing on the curved surface C2.

With these, side surface Sl, curved surface C1, side surface S2, curved surface C2
Printing is performed for half a circle leading to , and for the remaining half circle, flat printing is performed on the side surface S3 of the workpiece W (P5 to P6),
Rolling printing on curved surface C3 (P6-P7), flat printing on side surface S4 (P7-P8), rolling printing on curved surface C4 (P8-P8)
P9) are performed one after another. Then, when the curved surface C4 and the end of the first side surface S1 are connected, printing of the entire circumference of the workpiece (2) is completed.

According to this embodiment, the workpiece W is held in the workpiece rolling mechanism 40 and rolled on the planar screen 20,
Curved surface printing can be performed by sliding the squeegee 35 in synchronization with this, and screen printing can be performed all around the three-dimensional workpiece W using a flat screen printing machine IO.

At this time, for a workpiece W having a polygonal cross section with rounded corners, it is possible to easily print the entire circumference by combining flat printing and rolling printing of the corners. Especially in rolling printing, axis A
Rotation, closeness and separation from screen 20, squeegee 3
By synchronizing the feeding in the sliding direction of 5, the workpiece W can always be rolled in close contact with the screen 20,
It is possible to perform reliable rolling printing.

Further, for a cylindrical workpiece W, the workpiece W is not fed in the same direction as the squeegee 35, but the workpiece W is rotated so that the circumferential speed matches the feed speed, and printing can be performed all around the circumference by constant rolling.

Furthermore, for the prismatic workpiece (2), printing is performed with any side surface brought into close contact with the screen 20, and the workpiece is sequentially rotated so that the other side surface comes into close contact with the screen 20. By repeating plane printing, all-around printing can be performed.

The shapes of these workpieces W need only be set in advance in the control means 80, and the rest of the printing is performed automatically, so that the work can be omitted.

On the other hand, in this embodiment, by adding the work rolling mechanism 40, the present invention can be easily implemented using an existing flat screen type printing machine IO.

Further, since there is no need for a dedicated screen or the like corresponding to the workpiece W, problems such as complication of replacement work and increase in cost depending on the workpiece W can be avoided.

Note that the present invention is not limited to the above embodiments,
Modifications within the scope of realizing the present invention are included in the present invention.

For example, the specific configuration of the control means 80 may be set as appropriate during implementation, and when storing cross-sectional shape data, there may be a method of separately inputting previously measured cross-sectional shape data;
It is possible to adopt a method of reading an image, a method of providing an optical type or a contact type shape sensor in the work rolling mechanism 40, and measuring the shape before printing, etc.

In addition to the one that operates based on pre-stored shape data, the workpiece rolling mechanism 40 may be equipped with an optical sensor, a contact sensor, or the like to measure the contour position of the held workpiece W in front of the printing section position. The movement of the workpiece rolling mechanism 40 may be feedback-controlled to maintain close rolling.

On the other hand, the mechanism for rotating the workpiece W in the workpiece rolling mechanism 40, feeding it along the screen 20, moving it close to and away from the screen 20, etc. is not limited to the structure of the embodiment described above. is screen 2
The 0 side may be driven, and may be appropriately designed in implementation.

Further, the structure of each part of the printing press 10 may be appropriately selected in implementation, and the form of the screen 20, the holding structure, the peripheral structure of the squeegee 35, etc. may also be arbitrary, and the present invention can be applied to various flat screen printing machines. It is applicable.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to perform curved surface printing by rolling a three-dimensional work onto a flat screen. This makes it possible to print all around the area.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 is a front view showing the embodiment, Fig. 3 is a block diagram showing the control means of the embodiment, and Fig. 4 is a diagram showing the control means of the embodiment. It is a schematic diagram showing operation. IO... Screen printing machine for all-round printing, 20... Screen, 40... Workpiece rolling mechanism, 50... Proximity/separation means, 60... Parallel movement means, 70... Rotation holding means ,■...Work. Applicant NST Co., Ltd.

Claims (3)

[Claims] (1) A screen printing machine that transmits ink supplied from the front surface of a planar screen to the back surface as a predetermined image, and a work rolling mechanism that sequentially rolls the peripheral surface of a three-dimensional work in close contact with the back surface of the screen. A screen printing machine for all-round printing, characterized in that it has: (2) In claim 1, the workpiece rolling mechanism includes a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and a rotating holding means for rotating the held workpiece around a rotation axis along a screen, and rotating the workpiece according to a circumferential speed of the workpiece at a position facing the screen. A screen printing machine for all-round printing, comprising a parallel movement means for moving in a direction that intersects the rotation axis and parallel to the screen. (3) In claim 1 or 2, the workpiece rolling mechanism includes proximity/separation means for moving the workpiece close to and away from the screen so that the circumferential surface of the workpiece at a position facing the screen comes into close contact with the screen. A screen printing machine for all-round printing, characterized in that it has: