Electronic component package tape and method of manufacturing the same

Abstract

An electronic component package tape comprising a carrier tape of belt-like form storing electronic components in storage pockets formed into a concaved box shape at predetermined pitches, a cover tape of ribbon-like form bonded to the carrier tape to seal upper openings of the storage pockets, and first protrusions, each having a tip of rounded surface formed on an underside surface of the cover tape facing the electronic components. The storage pockets may be provided with a second protrusion formed in an upwardly protruding manner on a bottom surface thereof. In a method of manufacturing the electronic component package tape, the cover tape is held between a first and a second rotating bodies. Both of the rotating bodies are rotated to form protrusions on the cover tape, which is bonded to an upper surface of the carrier tape in a manner to cover openings of the storage pockets.

Description

FIELD OF THE INVENTION

The present invention relates to a belt-like electronic component package tape containing electronic components used primarily for automated mounting on wiring boards and the like of a variety of electronic apparatuses. The invention also relates to a method of manufacturing the same.

BACKGROUND OF THE INVENTION

In recent years, automated mounting of electronic components on wiring boards has made considerable progress in manufacture of various electronic apparatuses, and there is a continuous rise that such electronic components as switches, variable resistors and the like devices are packed and delivered in the form of package tapes, in which the electronic components are stored individually in large number of storage pockets in an embossed tape configuration.

Description is now provided of one such electronic component package tape of the prior art with reference to FIG. 4 and FIG. 5.

FIG. 4 is a sectional view of an ordinary electronic component package tape. In FIG. 4, carrier tape 301 made of an insulation film in a belt-like form has a plurality of storage pockets 311 of generally a concaved box shape formed in a consecutive manner at predetermined pitches. Electronic components 302 such as switches and variable resistors are stored individually in these storage pockets 311 in the same orientation.

Cover tape 303 of a ribbon-like form made of an insulation film is bonded to an upper surface of carrier tape 301 to seal the openings of storage pockets 311. The electronic component package tape is thus constructed.

The electronic component package tape of this kind is wound into a roll on a reel for transportation (not shown), and packed for storage and the subsequent shipment. The transportation reel is loaded on an automatic mounting machine (not shown) when electronic components 302 are mounted on wiring boards and the like (not shown) of the electronic apparatuses.

The belt-like electronic component package tape is pulled out of the transportation reel by the automatic mounting machine, and after cover tape 303 is peeled off upward, a suction head (not shown) of the automatic mounting machine holds and picks up electronic components 302 one after another from storage pockets 311 of carrier tape 301, and places them in predetermined positions on the wiring boards. Electronic components 302 are hence mounted on the wiring boards by reflow soldering or the like method.

There occasionally occurs a problem during the automated mounting operation that electronic component 302 sticks to the underside of cover tape 303 and comes out of the carrier tape 301 when cover tape 303 is peeled off carrier tape 301, if a surface of electronic component 302 is stained with oil or the like substance.

For this reason, cover tape 303 is so formed that the underside surface is provided with a plurality of protrusions 332, each having hole 331 in the center, as shown in the sectional view of FIG. 5, in order that electronic components 302 can come into close proximity of protrusions 332 having less surface areas to contact instead of the entire surface of cover tape 303. The electronic component package tape devised and formed in this manner prevents electronic components 302 from sticking onto the underside surface of cover tape 303 even when electronic components 302 are stained with oil and the like substances, thereby avoiding problems in the automated mounting operation.

One example of the prior art publications known to be relevant to the invention of this application is Japanese Patent Unexamined Publication, No. H04-31215.

In the electronic component package tape of the prior art, as illustrated above, it is likely that the automated mounting operation is interfered due to sticking of electronic components 302 when cover tape 303 used has a flat surface as shown in FIG. 4. On the other hand, when cover tape 303 is provided with protrusions 332 having holes 331 as shown in FIG. 5 to prevent this problem, there gives rise to another problem that holes 331 in protrusions 332 allow dust and the like particles to get into storage pockets 311 during transportation, and the dust enters inside electronic components 302 such as switches and variable resistors, possibly resulting in malfunctioning of electronic components 302.

SUMMARY OF THE INVENTION

An electronic component package tape of the present invention comprises a carrier tape of belt-like form storing electronic components in a plurality of storage pockets formed into a concaved box shape at predetermined pitches, a cover tape of ribbon-like form bonded to the carrier tape to seal upper openings of the storage pockets, and first protrusions, each having a tip of rounded surface, formed on an underside surface of the cover tape facing the electronic components.

This structure, provided with the protrusions of rounded surface and no hole, prevents dust and the like particles from getting into the storage pockets, and the electronic components from sticking to the underside surface of the cover tape due to oil and the like substances, thereby achieving the electronic component package tape capable of ensuring reliable operation of the automated mounting.

Furthermore, a method of manufacturing electronic component package tapes of the present invention comprises a step of holding a ribbon-like cover tape between a first rotating body having a plurality of convex portions formed at predetermined pitches around the periphery thereof and a second rotating body having concave portions formed around the periphery thereof in a corresponding manner to the convex portions, a step of forming protrusions of rounded surface on the cover tape by rotating the first rotating body and the second rotating body, and a step of bonding the cover tape formed with the protrusions to an upper surface of the belt-like carrier tape in a manner to cover openings of storage pockets formed in the carrier tape for carrying electronic components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of an electronic component package tape according to one exemplary embodiment of the present invention;

FIG. 2 is a plan view of the electronic component package tape shown in FIG. 1;

FIG. 3 is a schematic drawing illustrating the steps of manufacturing the electronic component package tape shown in FIG. 1; and

FIG. 4 and FIG. 5 are sectional views of electronic component package tapes of the prior art.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Description is provided of an exemplary embodiment of the present invention with reference to FIG. 1 to FIG. 3. FIG. 1 is a sectional view of an electronic component package tape according to the exemplary embodiment of this invention, FIG. 2 is a plan view of the electronic component package tape shown in FIG. 1, and FIG. 3 is a schematic drawing illustrating the steps of manufacturing the electronic component package tape shown in FIG. 1.

According to this exemplary embodiment of the invention in FIG. 1, the electronic component package tape comprises belt-like carrier tape 11 carrying electronic components 2 in a plurality of storage pockets 11A formed into a concaved box-like shape at predetermined pitches, ribbon-like cover tape 12 bonded to carrier tape 11 to seal upper openings of storage pockets 11A, and first protrusions 12B having rounded tips formed on an underside surface of cover tape 12 facing electronic components 2.

In addition, second protrusions 11B may be formed on a bottom surfaces of storage pockets 11A in a manner to protrude upward.

Description is provided in more detail of the structure of the electronic component package tape according to this exemplary embodiment of the invention.

Carrier tape 11 is a belt-like form made of an insulation film such as polystyrene and the like materials. This carrier tape 11 is provided with a plurality of storage pockets 11A of generally a concaved box-like shape formed in a consecutive manner at predetermined pitches in a longitudinal direction thereof.

Formed on bottom surfaces of storage pockets 11A are a plurality of protrusions 11B (i.e., second protrusions) protruding upward and a recess 11C in the center bottom surface of each of storage pockets 11A. Carrier tape 11 also has sprocket holes 11D formed at predetermined pitches along one side orthogonal to a widthwise direction thereof.

These storage pockets 11A individually contain electronic components 2 such as switches and variable resistors having terminals and control knobs extending sideway in the same orientation.

Cover tape 12 is a ribbon-like form made of an insulation film such as polyethylene terephthalate and the like materials. This cover tape 12 is provided with adhesive layers of a thermo-compression type along sealing areas 12A at both sides of its lower surface, which bond cover tape 12 to an upper surface of carrier tape 11 in a manner to seal the upper openings of storage pockets 11A.

Furthermore, there are a plurality of protrusions 12B (i.e., first protrusions), each having a tip of generally a rounded surface formed on the underside surface of cover tape 12 facing electronic components 2 in a protruding manner with a small space to upper surfaces of electronic components 2. The electronic component package tape is constructed as above.

In other words, the electronic component package tape of the present invention is not provided with any hole in protrusions 12B formed to protrude on the underside surface of cover tape 12, and this cover tape 12 prevents dust and the like particles from getting into storage pockets 11A containing electronic components 2 since it is bonded to carrier tape 11 along sealing areas 12A at both sides of and covers the upper openings of storage pockets 11A.

In addition, carrier tape 11 is provided with protrusions 11B formed upward on the bottom surfaces of storage pockets 11A. Since protrusions 11B make electronic components 2 not liable to stick to the surface of carrier tape 11, they help make electronic components 2 easily removable from storage pockets 11A during automated mounting, thereby achieving the automated mounting operation more reliable.

Description is provided next of a method of manufacturing the electronic component package tape of the structure discussed above with reference to FIG. 3. In order to help make structures of the individual elements more comprehensible, FIG. 3 illustrates certain elements with a different scale of magnification.

In FIG. 3, first rotating body 13 is provided with convex portions 13A at predetermined pitches around its periphery. Second rotating body 14 has concave portions 14A formed around its periphery in locations corresponding to convex portions 13A. First rotating body 13 and second rotating body 14 are so arranged as to face each other with convex portions 13A in engagement to concave portion 14A around their peripheries, and that both rotating bodies are rotatable in a synchronized motion.

A ribbon-like tape material supplied from the left side of the drawing passes through the peripheries of first rotating body 13 and second rotating body 14 as they rotate, while being held between convex portions 13A and concave portions 14A. Hence produced is ribbon-like cover tape 12 formed with protrusions 12B having the tips of generally the rounded surface at the predetermined pitches.

In this case, cover tape 12 has a thickness not smaller than 50 μm but not greater than 70 μm, and protrusions 12B of the rounded surfaces are formed into a height not smaller than 0.1 mm but not larger than 0.3 mm at such pitches so that at least two protrusions 12B confront an upper surface of each of the electronic components.

In this embodiment here, protrusions 12B are not likely to maintain their protruding shape because they tend to get flattened if the height is smaller than 0.1 mm, or protrusions 12B become liable to break and cover tape 12 tend to get wrinkled if the height exceeds 0.3 mm.

In other words, it is desirable to form protrusions 12B of such a height that a ratio of the height to the thickness of cover tape 12 generally becomes not smaller than 1.5 but not larger than 6, and more preferably in a ratio between 2 and 4.

As an alternative way of forming such protrusions 12B on cover tape 12, there is another method, in which the tape material is supplied by a feeding device to make it pass through intermittently between a vertically reciprocating punch and a base plate with a bored hole corresponding to the punch. When compared with this method, however, the method discussed above for forming protrusions 12B by passing the tape material between first and second rotating bodies 13 and 14 can make the complex feeding device unnecessary, and form protrusions 12B easily and continuously at a faster rate.

Cover tape 12 having protrusions 12B formed in this manner is guided downward, and placed on top of carrier tape 11 supplied from the right side of the drawing in a manner that the tips of protrusions 12B confront small electronic components 2 such as detector switches stored in a predetermined orientation inside storage pockets 11A.

Following the above, overlapped cover tape 12 and carrier tape 11 pass through sealing device 15 equipped with a heater (not shown), a press punch (not shown) and the like, whereby sealing areas 12A on the underside surface of cover tape 12 are heated and pressed, to complete the electronic component package tape consisting of cover tape 12 bonded to the upper surface of carrier tape 11 containing electronic components 2 in its storage pockets 11A.

Electronic component package tape of this type is wound into a roll on a reel for transportation (not shown), and packed for storage and the subsequent shipment. The transportation reel is loaded on an automatic mounting machine (not shown) when electronic components 2 are mounted on wiring boards and the like (not shown) of electronic apparatuses.

The belt-like electronic component package tape is pulled out of the transportation reel by the automatic mounting machine, and after cover tape 12 is peeled off upward, a suction head (not shown) of the automatic mounting machine holds and picks up electronic components 2 one after another from storage pockets 11A of carrier tape 11, and places them in predetermined positions on the wiring boards. Electronic components 2 are then mounted on the wiring boards by means of reflow soldering or the like method.

Since protrusions 12B of generally the rounded surface of cover tape 12 confronting upper surfaces of electronic components 2 result in reduction of an area of contact between protrusions 12B and the upper surfaces of electronic components 2, this embodiment can prevent electronic components 2 from sticking to cover tape 12 when cover tape 12 is being peeled off from carrier tape 11 even if electronic components 2 are stained by any chance with oil or the like substance, thereby ensuring reliability of the automated mounting to wiring boards.

Moreover, since the underside surfaces of electronic components 2 are in contact with protrusions 11B on the bottom surfaces of storage pockets 11A, which also results in reduction of an area of contact between them, this structure can prevent electronic components 2 from sticking to the bottom surfaces of storage pockets 11A, and help make electronic components 2 easily removable from storage pockets 11A.

According to the present exemplary embodiment, as described, protrusions 12B having the tips of generally the rounded surface are formed without hole on the underside surface of cover tape 12 facing electronic components 2. Protrusions 12B can therefore prevent dust and the like particles from getting into storage pockets 11A, and avoid the electronic components from sticking to the underside surface of cover tape 12 due to oil and the like substances, thereby achieving the electronic component package tape capable of ensuring reliable operation of the automated mounting.

Electronic components 2 such as switches and variable resistors are provided with moving members like control knobs and the like as compared with passive components such as semiconductors and capacitors. It is therefore especially important to keep such mechanical components free from dust during transportation and storage because of the possibility that intended operation of the moving members is impaired if dust entered into storage pockets 11A reaches inside of the switches and the like.

The presence of protrusions 11B formed to project upward from the bottom surfaces of storage pockets 11A of carrier tape 11 reduces the areas of contact where the underside surfaces of electronic components 2 rest upon these protrusions 11B, and prevents electronic components 2 from sticking to carrier tape 11. This helps ease the removal of electronic components 2 from storage pockets 11A in the automated mounting, and ensures reliable operation of the automated mounting.

In addition, formation of recesses 11C in generally the center of the individual bottom surfaces of storage pockets 11A also reduces the area of contact with the underside surfaces of electronic components 2 even if protrusions 11B become deformed or flattened.

The presence of recesses 11C is also effective for reduction of the areas of contact between the bottom surfaces of storage pockets 11A and the underside surfaces of electronic components 2 when protrusions 11B are not provided. Accordingly, recesses 11C make electronic components 2 not liable to stick to carrier tape 11, help ease the removal of electronic components 2 from storage pockets 11A in the automated mounting, and thereby they ensure reliable operation of the automated mounting.

The electronic component package tape can be produced by a simple method, in which ribbon-like cover tape 12 is placed between first rotating body 13 having the plurality of convex portions 13A formed at predetermined pitches around the periphery thereof and second rotating body 14 having concave portions 14A formed around the periphery thereof in locations corresponding to convex portions 13A, and first and second rotating bodies 13 and 14 are rotated to form protrusions 12B of generally rounded surface on cover tape 12.

The electronic component package tape and the method of manufacturing the same according to the present invention have an advantageous feature of providing the product that is not likely to allow dust to get into the storage pockets, and useful for the electronic components and the like adapted primarily for automated mounting on wiring boards and the like for use in a variety of electronic apparatuses.

Claims

1. An electronic component package tape comprising:

a carrier tape of belt-like form storing electronic components in a plurality of storage pockets formed into a concaved box shape at predetermined pitches;

a cover tape of ribbon-like form bonded to the carrier tape to seal upper openings of the storage pockets; and

first protrusions, each having a tip of rounded surface formed on an underside surface of the cover tape facing the electronic components.

2. The electronic component package tape according to claim 1, wherein each of the storage pockets is provided with a second protrusion formed in an upwardly protruding manner on a bottom surface thereof.

3. The electronic component package tape according to claim 1, wherein each of the storage pockets is provided with a recess formed in a bottom surface thereof.

4. The electronic component package tape according to claim 2, wherein each of the storage pockets is provided with a recess formed in a bottom surface thereof.

5. The electronic component package tape according to claim 1, wherein the cover tape has a thickness not smaller than 50 μm but not greater than 70 μm, the first protrusions have a height not smaller than 0.1 mm but not larger than 0.3 mm, and at least two of the first protrusions confront an upper surface of each of the electronic components.

6. The electronic component package tape according to claim 1, wherein a ratio of a height of the first protrusions to a thickness of the cover tape is not smaller than 1.5 but not larger than 6.

7. A method of manufacturing electronic component package tape comprising the steps of:

holding a cover tape of ribbon-like form between a first rotating body having a plurality of convex portions formed at predetermined pitches around the periphery thereof and a second rotating body having concave portions formed around the periphery thereof in locations corresponding to the convex portions;

forming protrusions of rounded surface on the cover tape by rotating the first rotating body and the second rotating body; and

bonding the cover tape formed with the protrusions to an upper surface of a carrier tape of belt-like form in a manner to cover openings of storage pockets formed in the carrier tape for carrying electronic components.