JPS6221202B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing insulating sealing pellets used for sealing various electronic parts.

For example, electronic components such as printed wiring boards used in watches are sealed with resin using electrically insulating pellets in order to prevent other components from coming into contact with the board.

The pellets described above are generally small, about a few millimeters square, and have conventionally been produced by manually cutting them one by one from a wide long strip. Therefore, producing a large number of pellets of the same size not only requires a lot of time and effort, but also has the drawback of poor dimensional accuracy.

This invention was made as a result of studies aimed at eliminating the above-mentioned drawbacks, and provides a method for manufacturing sealing pellets in which the pellets can be cut automatically, efficiently, and with high precision. be.

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

As shown in Fig. 1, a heating oven 3 is placed at the entrance of a conveyance line formed by a group of parallel guide rolls and dancer rolls 2, and the pellet material A that has passed through the oven 3 is fed into the conveyance line. It can be done.

The pellet material A is made by uniformly scattering thermosetting resin composition powder on a sheet-like fiber base material 21 in front of the heating oven 3, as shown in FIG.
melting the powder during passage through the heating oven 3;
A semi-hardened molten solid layer 22 is formed on the fiber base material 21 by fusing and integrating the powders with each other and the powder and the fiber base material 21.

A nonwoven fabric is particularly suitable as the sheet-like fiber base material 21. Nonwoven fabrics include nonwoven fabrics made of various materials, such as organic fibrous nonwoven fabrics such as polyester nonwoven fabrics,
Glass paper, inorganic nonwoven fabric such as glass fiber nonwoven fabric, cellulose-mixed glass paper, paper, etc. are used.

Further, the thermosetting resin composition powder may be appropriately selected from well-known industrially usable synthetic resin powders that can be melted in a heating oven, such as epoxy resins, polyester resins, Examples include phenol resins and isocyanate resins. When used as a filler within a range that does not interfere with the sealing function, up to 70% by weight of the powder can be used in place of a thermoplastic resin component, and such materials are also included in the present invention. It is included in the range of thermosetting resin composition powder. The adhesive sheet B is supplied to the conveying line before the receiving roll 4 provided in the middle of the conveying line for the pellet material A fed into the conveying line, and the adhesive sheet B is applied to the lower surface of the pellet material A on the circumferential surface of the receiving roll 4. Adhesive sheets B are overlapped.

As shown in FIG. 4, this adhesive sheet B is formed of a support 31 such as a synthetic resin sheet, paper, or metal foil having the same width as the pellet material A, and an adhesive layer 32 provided on its upper surface. The pellet material A and the adhesive sheet B are pasted together by the adhesive layer 32.

A bonding roll 5 is arranged outside the receiving roll 4 to press the pellet material A and the adhesive sheet B to completely bond them together. A laminate C is formed.

Immediately above the receiving roll 4, a cutter roll 6 is provided which cuts the laminate C to be passed into several strips D along the longitudinal direction. This blade roll 6 has a large number of disc-shaped blades 7 on the outer peripheral surface of the roll body.
are attached at regular intervals in the axial direction, and the width of the strip D is determined by the interval between the blades 7.

The cutter roll 6 cuts the laminate C from the pellet material A to the adhesive sheet B, as shown in FIG. 5, to cut the laminate C into a large number of parallel strips D.

In addition, hot air is circulated and supplied to the locations where each guide roll 1, dancer roll 2, receiving roll 4, etc. are loaded to maintain a predetermined heating state, and in addition, hot water, etc., is supplied to the dancer roll 2. This prevents cracks from entering when the pellet material A is cut by the cutter roll 6, and allows for smooth running along the conveyance line.

The group of strips D cut by the cutter roll 6 is moved in a parallel state onto a hot plate 8 arranged horizontally in front. A pressure roll 9 is disposed above the hot plate 8, and a cutting blade 10 is disposed in front of the pressure roll 9. The pressing roll 9 serves to hold down each traveling strip D so that it does not move during cutting by the cutting blade, and at the same time serves to ensure the accuracy of the thickness of the pellet material A, and the hot plate 8 serves to prevent the pellet material A from moving during cutting. The pellet material is heated appropriately to prevent cracks from entering.

The cutting blade 10 is formed along the width direction of the pellet material A and is longer than the width of the material A, and is moved up and down by a lifting means such as a crank.

This knife 10 simultaneously makes cuts 11 in the width direction in the pellet material A of each strip D by its downward movement, and the downward stroke makes the cuts only in the pellet material, as shown in FIG. It is set so that it does not enter the adhesive sheet B located below it.

By passing directly under the cutting blade 10, cuts 11 are made in the pellet material A of each strip D at regular intervals, thereby making it possible to form resin pellets E in a predetermined shape, which become adhesive. They are arranged in sequence on sheet B.

An intermittent feed mechanism 12 is provided behind the cutting blade 10 to feed the strip D forward, and the laminate C consisting of the pellet material A and the adhesive sheet B is moved along the conveyance line.

This intermittent feed mechanism 12 includes an air cylinder 13 that extends and contracts through a set stroke, and a clamp 1 that is moved forward and backward by this cylinder 13.
4, and is adapted to intermittently feed the band D group forward by a constant stroke by the expansion and contraction of the cylinder 13 and the vertical movement of the clamp 14.

That is, the clamp 14 that clamps the strip D is the first
You will perform a walking exercise as shown by the arrow in the figure. While the band D group is being moved by the intermittent feeding mechanism 12, the cutting blade 1 described above is
0 waits in the raised position, and moves downward to make the cut 11 when the strip D stops while the intermittent feed mechanism 12 returns to the retreated position.

Note that the length of the resin pellet E is determined by the amount of feed of the strip D by the intermittent feed mechanism 12, so the extension and contraction stroke of the cylinder 13 can be adjusted to adjust the feed amount according to the required pellets. .

Furthermore, the above-mentioned cutting blade 10 is not only a straight blade that makes cuts in the width direction of the pellet material A as shown in FIG. 7, but also a blade that makes cuts that match the shape of the sealed part of the electronic component. do not have.

The strip D fed forward by the intermittent feed mechanism 12 is made of a resin pellet E having a predetermined width, which is the object of the present invention, pasted onto a strip-shaped adhesive sheet B as shown in FIG. structure,
This belt state D advances on the workbench 15 in front of the feed mechanism 12, and after passing the workbench 15 is wound up.

Two types of winding can be adopted: one is to wind the strip D as it is into a roll, and the other is to automatically peel off the resin pellet E and take it out and then wind only the adhesive sheet B.

In the former case, as shown by solid lines in FIG. 1, a plurality of take-up rolls 16 are arranged at the bottom of the workbench 15, and adjacent strips D are sequentially wound onto different rolls.

In the latter case, the strip D is bent at an acute angle by a guide 17 placed in front of the workbench 15, as shown by the dashed line in FIG. E is automatically peeled off and stored as a single unit in the container 19.

The former resin pellets E, which are wound onto a roll while still attached to the adhesive sheet B, are automatically peeled off in the next step and attached to electronic components, and the peeled resin pellets stored in the latter container 19 are E is attached to electronic components by hand. In this invention, the adhesive strength (180° peel test value) between the adhesive layer of the adhesive sheet and the sealing pellet is usually 50 to 200 g (sample width 8.8 mm, tensile speed
300mm/min, 22℃).

As described above, according to the present invention, a long strip of pellet material and an adhesive sheet are overlapped and bonded while traveling in the longitudinal direction, and this laminate is cut into a plurality of strips along the longitudinal direction. Since cuts are made only in the width direction of the pellet material, resin pellets can be produced automatically and efficiently, and pellets are mechanically cut, making it possible to obtain pellets with high dimensional accuracy. It is.

In addition, since the pellets are completed while being pasted onto the strip-shaped adhesive sheet, they can be easily transferred to other peeling processes or can be continuously peeled off, and can also be continuously pasted onto electronic component sealing parts in the next process. Since the process can be carried out in a single step, there is no need to separate the front and back sides of the pellets, and it has the excellent effect of producing resin pellets of great practical value at low cost.

In this invention, the sheet-like base material has been explained using a fiber base material as an example, but it goes without saying that plastic films such as polyester film, heat-resistant polyester film, polypropylene film, paper, etc. may also be used. It is.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the steps of the pellet cutting method according to the present invention, Fig. 2 is a plan view, and Fig. 3 is a plan view.
The figure is an enlarged sectional view of the pellet material, Fig. 4 is an enlarged sectional view of the adhesive sheet, Fig. 5 is an enlarged sectional view of the part where the laminate is cut into strips, and Fig. 6 is an enlarged sectional view of the pellet material of the strip. This is an enlarged cross-sectional view of the seventh
The figure is a perspective view of the pellets obtained. 3... Heating oven, 4... Receiving roll, 5...
Laminating roll, 6...Blade roll, 7...Blade, 9...Pressure roll, 10...Cutting knife, 1
DESCRIPTION OF SYMBOLS 1... Cut, 12... Intermittent feeding mechanism, 21... Sheet-like fiber base material, 22... Semi-cured molten solid layer, A... Pellet base material, B... Adhesive sheet, C
...Laminated body, D...Strip piece, E...Resin pellet.

Claims (1)

[Claims] 1 A long belt-like pellet material with a semi-cured molten solid layer formed on a base sheet-like base material and an adhesive sheet are overlapped and adhered while running in the longitudinal direction, and this laminate is bonded along the longitudinal direction. 1. A method for manufacturing sealing pellets, which comprises cutting the pellet material into a plurality of strips, and then cutting the pellet material of each strip in the width direction at predetermined intervals.