JP3624260B2 - Cutting method of printed circuit board - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for cutting a printed circuit board, which is useful for cutting a printed circuit board made of a long strip-like electrically insulating flexible film into a predetermined shape.
[0002]
[Prior art]
Conventionally, in order to electrically connect a display device mainly composed of an LCD to a driving electronic circuit board in a small electronic device such as a calculator or electronic notebook, a conductive ink is placed on an electrically insulating substrate such as polyester or polyimide. An electrical circuit is formed using a metal foil, etc., and a printed circuit board provided with an adhesive layer or a resist layer as necessary is punched into a desired shape, cut, etc. Heat-sealed to the substrate.
These heat seal connectors need to be flexible and flexible in order to efficiently route the wiring in a limited space in the miniaturized electronic equipment containers, and to maintain the heat seal strength Since it is necessary to efficiently transmit the sealing temperature and pressure at the time of heat sealing, a polyester film of 15 to 30 μm is usually used as a flexible film as a base material.
Furthermore, in electronic devices that are miniaturized, the connection pitch of electronic circuit boards, LCDs, and the like is also miniaturized, and precision is also required in alignment with heat seal connectors. That is, there is a demand for refinement of the print pitch of the heat seal connector and improvement in alignment accuracy between the print pattern and the outer shape in cutting to a desired shape.
[0003]
[Problems to be solved by the invention]
However, ultra-thin films are generally very poor in workability, and in order to improve this, and to make the formation of electrical circuits and cutting to the desired shape with precision, in order to complement the rigidity of ultra-thin films Usually, a mount is used as a carrier.
However, if the adhesion between the heat seal connector and the mount is too good, it will be difficult to peel off the mount during the heat sealing operation, and if it is not in close contact, it will not be able to be transported during production and will not be useful as a carrier. It was difficult to adjust appropriately.
Therefore, various measures have been conventionally taken in order to make the adhesiveness with the mount appropriate when cutting the printed circuit board. In other words, if the surface of the backing is smooth, the backing and the printed circuit board will be in a vacuum state and will be in close contact with each other. In addition to using specially processed paper that shows the properties of the printed circuit board, the printed circuit board "Kaeri" is used to fix it to the mount using a cutting blade.
However, specially processed paper with irregularities and Teflon coating is naturally costly, and it is extremely difficult to keep the amount of “burr” at the time of trimming uniform, and the holding power when fixed varies. It was easily peeled off during the process, or could not be peeled off from the mount when used as a printed circuit.
When using a mount for the purpose of transporting only the printed circuit board, there is a method to heat-seal the printed circuit board at an unnecessary part and fix it. It will disappear, and the mount and the product will fall apart.
[0004]
On the other hand, in order to increase the cutting accuracy of the printed circuit board, a method for cutting and positioning image processing marks is provided on the printed circuit board and the position is corrected by image processing. If the adhesiveness is insufficient, the printed circuit board will not be rigid enough to float up from the mount, leading to imperfect reading of the cutting alignment mark and inaccurate positioning, resulting in cutting misalignment. .
For example, when a flexible film having a size of 500 mm × 500 mm is used as a substrate of a printed circuit board, it is extremely difficult to handle during the manufacturing process due to lack of rigidity, and the productivity is remarkably inferior. As a solution, for example, a roll-to-roll method has been adopted in which a belt-like flexible film having a width of 500 mm × 1000 m is used and the transport process is mechanized.
When cutting the printed material of this strip-like flexible film, if the adhesiveness between the printed circuit and the mount after cutting is weak, it becomes difficult to take out the products cut in roll-to-roll form from the cutting part and accumulate them. The circuit and the mount will fall apart.
The present invention solves the above-described conventional problems, and solves the adhesion between the printed circuit board and the mount represented by such a heat seal connector, and has sufficient adhesion due to static electricity during production. It is another object of the present invention to provide a method for cutting a printed circuit board that can be easily peeled off by simply removing the charge when used as a printed circuit after forming a product shape.
[0005]
[Means for Solving the Problems]
Cutting method of a printed circuit plate precursor according to the present invention includes a printed circuit plate precursor consisting Tou film electrically insulating Allowed, this overlay and backing sheet to impart rigidity and enhanced by static electricity generated by the charging equipment that adhesion Then, it is cut into a predetermined shape.
[0006]
[Action]
According to the present invention, the printed circuit board is not subjected to any chemical or thermal change since the adhesion to the mount is obtained by static electricity generated by the charging device. In addition, since there is no physical deformation such as pressurization with the mount to obtain adhesion, there is no defect such as disconnection due to bending of the printed circuit.
Moreover, not only the parts used as products, but also the alignment marks for cutting positioning can ensure sufficient adhesion without leaving any effect on the quality of the product, so the cutting positioning marks do not lift up and cutting with high precision is possible. Is possible. Adequate adhesion is maintained for the part used as a product, so even if it is cut by a roll-to-roll cutting machine, it can be easily taken out from the cutting part without peeling off from the mount even if it becomes a product shape Is possible.
Further, since the adhesive strength with the mount depends on static electricity, it is possible to arbitrarily set the adhesive strength at a location where adhesion is required and an unnecessary location by controlling the charge amount during the manufacturing process.
[0007]
Hereinafter, a method for cutting a printed circuit board according to the present invention will be described in detail with reference to the drawings.
FIG. 1 shows an outline of an apparatus for carrying out a method for cutting a printed circuit board according to the present invention. In FIG. 1, A is a bonding step, B is a first cut step, and C is a second cut step. 2 is a bonding process part A, FIG. 3 is a detailed view of each of the first cutting process part B and the second cutting process part C, and FIG. 4 is a schematic diagram showing a product removal method in the second cutting process part C. .
In the bonding process section A, the printed circuit board 3 and the mount 4 supplied from the unwinding machines 1 and 2 are roughly aligned by the bonding roll 5, and then the electrostatic charging device 6 installed immediately thereafter is installed. Adhesion is given by electrostatic force when passing.
As described above, a polyester film having a thickness of 15 to 30 μm is used for the printed circuit board 3, but a polyimide film having a similar thickness may be used. In addition, a synthetic paper YUPO (trade name, manufactured by Oji Yuka Co., Ltd.) based on polyethylene resin is used as a mount for imparting rigidity to the printed circuit board.
The printed circuit board 3 and the mount 4 may be a combination of materials having little adhesion to each other.
[0008]
The superposed product 7 is then conveyed to the first cutting process part B. Here, the position of a cutting alignment mark (not shown) on the printed circuit board 3 is corrected by an image processing apparatus and then cut to a predetermined width.
At this time, if the printed circuit board and the mount are not sufficiently in contact, the printed circuit board will not be rigid, so it will rise up from the mount, and the cutting alignment mark will be read incompletely, resulting in inaccurate positioning. Therefore, it is desirable to increase the amount of static electricity of the electrostatic charging device 6 to give a strong adhesion to the stacked product 7.
If the camera 8 for image processing of the reference print pattern is arranged on the extended line of the cutting blade 9, the reference print pattern can be imaged immediately before cutting, and the cutting blade bites at the time of cutting to print the thickness of the cutting blade. Even if the circuit original plate is displaced, it can be corrected directly by image processing, which is desirable.
As a CCD camera used for image processing, it is desirable to use an ultra-compact type such as IK-M40MF (trade name, manufactured by Toshiba), CS3150 (trade name, manufactured by Tokyo Denki Kogyo Co., Ltd.). And the distance between the reference print patterns can be reduced, and the number of print patterns to be cut that can be formed on one printed circuit original plate can be increased.
[0009]
The drive device (not shown) that applies the cutting force to the cutting blade may be a hydraulic cylinder, pneumatic cylinder, crank unit, etc. that are normally used in a punching machine, and a CCD camera, which is an electronic component, is installed near the cutting blade. Therefore, it is preferable to use a hydraulic cylinder with as little vibration as possible since image processing is performed.
If the camera is placed on the extended line of the cutting blade, the cutting blade will not be sharp and it will be necessary to fix the cutting blade precisely on the center line of the camera when the cutting blade is replaced. Since it can be corrected by the control software, it is preferable to design the control software as such.
The superposed product 7 that has passed through the first cut process part B is conveyed to the second cut process part C,
A product 10 having a predetermined shape is formed by cutting in a direction perpendicular to the first cutting process part B.
In the first and second cutting process parts B and C, since the flexible film to be cut has a long band shape and cannot move during alignment (for example, a guide rail for linear movement) 11. A moving mechanism (such as a linear moving drive ball screw 12) must be provided on the cutting device side. The drive device and the device for controlling the drive device may be configured by combining a ball screw, a servo motor, a pulse motor, and the like in addition to a commercially available robot controller combination.
[0010]
The driving system for transporting the belt-shaped printed circuit board to the first and second cutting process parts B and C is a flat plate rather than the conventional pinch roll system using a combination of a rubber roll and a metal roll. It is preferable to use a grip feed system having a gripping mechanism 13 (see FIG. 1). That is, according to the pinch roll method, a curved surface portion is always generated in the pinch portion, and a force to peel off the adhesion due to electrostatic force is applied, but in the grip feed method, there is no curved surface portion and there is no fear of causing a peeling force.
For example, if the grip feed type gripping mechanism 13 is provided at one location after the second cutting step B, the distance from the laminating roll 5 to the gripping mechanism 13 becomes long, and sagging due to the weight of the belt-like film occurs. Since a shearing force is generated on the adhesive film and the backing sheet and the adhesion force is lowered, it is preferable to provide it before and after the first cutting process part B and before and after the second cutting process part C, respectively, so that no sagging occurs. .
This grip feed type gripping part is preferably a non-printing part that divides one block of the printed circuit so as not to apply unnecessary pressure to the printed circuit board. It is desirable to arrange the gripping mechanism 13 in the first and second cutting process parts B and C, and the laminating roll 5 may be continuously pressure-bonded during conveyance. Since it is not preferable to pressurize the printed part when it is stopped in the second cutting process parts B and C, the position of the laminating roll 5 is also determined in consideration of the length of one pitch of the printed circuit. Is desirable.
In order to transport the belt-shaped printed circuit board by the transport mechanism, the transport mechanism part moves together with the printed circuit board, but on the suction plates (not shown) of the first and second cutting process parts B and C. In this case, the printed circuit board moves while being rubbed on it, and it is considered that the frictional force hinders transportation. It is better not to.
[0011]
The product 10 cut into a predetermined shape in the second cut process part C is sucked and transferred to the product suction plate 14 installed on the back surface of the second cut process part C, and is accumulated in the dedicated stock container 15.
The product suction board 14 has a suction hole on the lower surface, and includes a hand mechanism 16 that reciprocates between the second cutting process part C and the dedicated stock container 15, and sucks the product 10 cut by the second cutting process part C. While being transferred to the dedicated stock container 15. In order to reliably transfer the product 10 from which the product suction plate 14 has been cut out together with the mount, it is necessary to provide sufficient adhesion also in the second cut process part C. For this reason, it is desirable to install the electrostatic charging device 6 not only immediately after the laminating roll 5 but also immediately before the second cutting process part C.
[0012]
【Example】
Using a Kasuga Electric KTS-1 type electrostatic charging device 6 and applying an electric length of 2 kV to a charging electrode of 500 mm in length, maintaining a 50 mm gap between the printed circuit board and the backing sheet, and at a speed of 200 mm / sec. When moved, the holding force in the shearing direction was 2 kg or more, and 20 kg or more in the peeling direction. When this was neutralized using a static eliminator manufactured by the same company, the holding force in the shearing and peeling direction was 1 g or less and could be easily peeled off.
[0013]
【The invention's effect】
According to the printed circuit board cutting method of the present invention, since the printed circuit board and the mount are brought into close contact with each other by the electrostatic force generated by the charging device , the adhesion force can be easily controlled by the applied voltage of the charging electrode. In addition, since there is no lift from the mount, the readability of the positioning mark is improved, high-precision cutting is possible, and since there is no peeling when the product is taken out, the process can be unmanned and automated.
[Brief description of the drawings]
FIG. 1 is a side view of an apparatus showing an embodiment of the present invention.
FIG. 2 is a side view showing details of a bonding process section A of the apparatus shown in FIG.
FIG. 3 is a side view showing details of a first cutting process part B and a second cutting process part C of the apparatus shown in FIG. 1;
4 is a side view showing an outline of a method for taking out a product in a second cutting process section C of the apparatus shown in FIG. 1. FIG.
[Explanation of symbols]
A ... Bonding process part, B ... First cut process part,
C ... 2nd cutting process part, 1, 2 ... Unwinder,
3 ... Printed circuit board, 4 ... Mount,
5 ... Lamination roll, 6 ... Electrostatic charging device,
7: Superposed product 8: Camera,
9 ... Cutting blade, 10 ... Product,
11. Linear motion guide rail, 12. Linear motion drive ball screw,
13 ... Grab mechanism, 14 ... Product suction board,
15 ... Dedicated stock container, 16 ... Hand mechanism.

Claims (1)

A printed circuit board made of an electrically insulative flexible film and a base sheet for providing rigidity are superposed on each other, and the adhesion is reinforced by static electricity generated by a charging device , and then cut into a predetermined shape. Cutting method for printed circuit board.

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