JP5436973B2 - Vacuum forming mold and carrier tape forming method - Google Patents

Description

  The present invention relates to an embossed carrier tape mold and a method for producing a carrier tape using the same.

  As a means for transporting electronic components and the like to a mounting machine, a carrier tape having an embossed portion formed on a tape-like base material is widely used. As a carrier tape, depending on the application, after removing a part of the base material by punching, a bottomed carrier tape is attached to the back surface of the base material to form a component storage part, or a part of the base material is used. An embossed carrier tape or the like that is processed into an embossed shape to form a component storage portion is used.

  As a carrier tape substrate, a thermoplastic resin substrate having an antistatic treatment or conductivity imparted to its surface has been used. In particular, an embossed carrier tape using this substrate is widely used because of its excellent cost and dimensional accuracy. Also, as a method of forming the emboss, a convex mold is arranged in the circumferential direction of the drum rotating in a fixed direction, and the heated tape-like substrate is sucked into the mold side by vacuum to form a convex shape. "Rotary male vacuum forming" is used in which embossing is formed by drawing around the mold. This is characterized by the fact that the same molding is repeated every round, so that the accumulated error of the dimension between the formed pockets is extremely small, and the high dimensional accuracy inside the pocket can be obtained. This is because it is suitable for manufacturing carrier tapes for applications that require high feed accuracy. (See Patent Document 1)

However, in this molding method, the root of the mold convex portion, that is, the shape of the pocket opening of the carrier tape is not sufficient due to the molding principle, and the curvature radius of the opening tends to increase. . If this radius of curvature is large, there will be a large gap between the tip and the inside of the pocket when the tip is stored, and the placement of the tip will be greatly limited. As a result, the arrangement of the chips in the pocket is displaced, which may cause trouble when the chips are mounted on the electronic device. As a method for solving such a problem, there has been proposed a method in which a portion of the preheated tape-shaped substrate that is in contact with the convex portion of the mold is heated again from the opposite side of the mold immediately before molding. (See Patent Document 2)
Further, in the specification of the conventional mold shown in FIG. 3, if a measure is taken to increase the width of the vacuum hole 24 for the purpose of reducing the radius of curvature, the heated sheet is drawn into the vacuum hole and the carrier tape is vacuumed. Since the transfer of the hole shape occurs, it is necessary to limit the width of the vacuum hole 24 to about 40 to 20% of the sheet thickness. In order to reduce the radius of curvature of the opening of the molded product formed using this mold. It was difficult to exhaust enough.
On the other hand, when manufacturing embossed carrier tapes with different pocket sizes, it is necessary to replace a set of the above-mentioned molds, which inevitably increases the capital investment cost, so a more efficient mold structure in such a case Was demanded.

Japanese Patent Laid-Open No. 7-088949 JP 2006-160369 A

The present invention maintains its features in rotary male vacuum forming, in which a cumulative error between pockets is small and high dimensional accuracy inside the pocket is obtained by a mold using the T-shaped mold 13 and a molding method. Further, it is an object of the present invention to provide a mold and a molding method for obtaining a pocket-shaped carrier tape in which the radius of curvature R of the portion from the surface of the pocket opening portion to the side surface of the component storage portion is as small as possible. To do.

As a result of intensive studies on the mold for forming the pocket portion by male molding, the present inventors have determined that the male portion for molding the pocket portion has a T-shape having a molding die head as described later. It is possible to obtain a large exhaust amount by exhausting through the gap on the back side of the mold head that leads to the vacuum hole, and the surface of the pocket opening portion and the pocket of the molded embossed carrier tape. The present inventors have found that the radius of curvature R between the side surfaces can be remarkably reduced and that the pocket size can be changed very easily.
That is, the first invention of the present invention is a male vacuum molding die for an embossed carrier tape comprising a side plate A11, a molding die 13, and a side plate B12, and satisfying the following requirements (a) to (d). .
(A) A mold 13 for forming a male mold is provided at the center of the groove formed by the groove side surface 111 and the groove bottom surface 112 of the side plate A and the groove side surface 121 and the groove bottom surface 122 of the side plate B.
(B) A plurality of mold heads 131 are formed on the mold foot 132 with a width larger than the width 133 of the mold foot, and a cross section of a portion corresponding to the head 131 from the mold foot 132 The shape is T-shaped.
(C) The vacuum holes 14 are provided on the mating surfaces of the side plates (11, 12) and the mold 13.
(D) There is a gap between the back surface 134 of the mold head and the bottom surface of both side plate grooves (112, 122).

The second invention is the above-described mold for rotary male vacuum forming, in which the side plates (11, 12) and the mold 13 are ring-shaped.
A third invention is an embossed carrier tape manufacturing method in which a part of a resin tape is brought into close contact with the mold head 131 of the mold using the above-mentioned mold, A heated resin tape is evacuated from the vacuum hole 14 and heated around the mold head 131 to form an embossed portion of the embossed carrier tape after heating the contacting portion. This is a mold vacuum forming method.
A fourth invention is a method for forming an embossed carrier tape, wherein the forming method is rotary male vacuum forming.
The fifth invention is an embossed carrier tape formed by using the above-mentioned mold, wherein the radius of curvature R of the portion from the surface of the pocket opening portion to the side surface of the component storage portion is 50 to 120% of the sheet thickness. .

In the rotary male vacuum forming in which the accumulated error between pockets is small and high dimensional accuracy inside the pocket is obtained by the mold and molding method of the present invention, the radius of curvature R of the pocket opening, which has been a problem in the past, is as small as possible. A pocket shape is obtained. In the mounting test of the electronic component using the obtained carrier tape, mounting defects can be suppressed extremely low. Furthermore, in the present invention, it is easy to change the pocket size, and it becomes easy to produce molded bodies of different sizes.

FIG. 1a is a cross-sectional view of a mold according to an embodiment of the present invention. FIG. 1 b is an explanatory view showing two embodiments (A and B) of the mold top view of the present invention. FIG. 1 c is an explanatory diagram showing another two embodiments (C and II) of the mold top view of the present invention. FIG. 2 is a conceptual diagram of the rotary male vacuum forming of the present invention. FIG. 3 is an example of a sectional view of a conventional mold in comparison with FIG. FIG. 4 is an example of a cross-sectional view of an embossed carrier tape formed using the mold according to claim 1.

An embodiment of an embossed carrier tape mold according to the present invention will be described.
FIG. 2 is a conceptual diagram of molding of the embossed carrier tape of this embodiment.
The slit resin tape 1 is preheated by the preheating device 2, and then heated to the molding temperature by the heating device 3, and by a plurality of molding dies (male dies) 5 continuously installed on the peripheral surface of the drum 4. An embossed carrier tape is formed by forming a pocket by rotary male vacuum forming, and cooling and winding with a cooler 6.

Specifically, first, the resin tape 1 is preheated. Here, as the resin tape 1, the sheet | seat which consists of resin which comprises the embossing carrier tape mentioned above is used. As will be described later, the thickness of the resin tape is preferably 0.2 mm or less in order to keep the curvature radius R of the bent portion small.
Examples of heating means in the preheating include an infra heater using a masking plate (infrared heater), an indirect heating method such as hot air blow, and a direct heating method in which a heat bar is brought into contact with the resin tape 1. According to such a heating means, only a predetermined place can be heated.

Next, the resin tape 1 is transferred to the molding die 5 by a certain amount. Examples of a method for transferring the resin tape 1 include a method using an air feeder, a gripper feeder, a roll feeder, and the like. A mechanism for feeding out the reel around which the tape is wound so as to synchronize with the rotational speed of the mold. If so, the above method need not be used.
In the vacuum molding machine, as shown in FIG. 2, the resin tape 1 is disposed above the surface of the molding die 5, and the surface of the resin tape 1 is placed close to the peripheral surface of the molding die 5 in parallel. Arrange.

Next, a portion of the resin tape 1 in contact with the male mold portion (hereinafter referred to as a mold contact portion) is heated again from the opposite side of the molding die 5 until just before molding using the heating device 3. As the heating device 3, the same heating means as the above preheating can be used.
Next, the resin tape 1 is evacuated through the vacuum hole 14 shown in FIG. 1 a of the molding die 5, and a part of the resin tape 1 is brought into close contact with the molding die 13 of the molding die 5. At this time, since the softened resin tape 1 is evacuated through the gap between the back surface 134 of the molding head and the bottom surfaces of both side grooves (112, 122), the root of the mold head 131, that is, the embossing obtained. An embossed carrier tape having a pocket portion with a very small radius of curvature R between the surface of the pocket opening portion of the carrier tape and the side surface of the component storage portion is obtained.
The width of the vacuum hole 14 in the tape flow direction may be the same as that of the mold head 131 as shown in FIG. 1B, or the mold head 131 as shown in FIG. It may be a narrow width of 50% or more of the width. The diagram on the right side of this figure schematically shows the shape of the AA ′ cross section in the case of (A) and the cross sectional shapes of BB ′ and CC ′ in the case of (B). In the section CC ′ in the case of (b), the side plates (11, 12) and the mold foot 132 are in close contact. Similarly, as shown in (c) and (2) of FIG. 1c, the vacuum hole 14 may be formed on the mold foot 132 side. The diagram on the right side of FIG. 1c schematically shows DD ′, EE ′ and FF ′ cross-sectional shapes as in FIG. 1b. As in the case of FIG. 1 b, the side plates (11, 12) and the mold foot 132 are in close contact.

  Then, the resin tape 1 is cooled to a temperature equal to or lower than the secondary transition point of the resin as a material to form an embossed pocket portion, and the embossed pocket portion is along the length direction by sequentially repeating this. Thus, a large number of embossed carrier tapes can be obtained.

  FIG. 3 shows an example of a conventional mold. In this mold, the mold 23 has the same head and foot widths, and the vacuum holes 24 include both side plates (21, 22) and the mold 23. In the evacuation through the vacuum hole 24, the radius of curvature R between the pocket opening surface of the embossed carrier tape and the side surface of the component storage portion is reduced by a certain value or more as described above. Can not do it.

  The metal material used in the mold of the present invention is not particularly limited as long as it is generally used in this type of mold, but SUS, copper, brass, aluminum or the like may be used. It is possible to use a material having a similar linear expansion coefficient when different materials are used in combination. Further, as a means for improving the mold releasability, surface treatment such as commonly used diamond-like coating (DLC), titanium coating, fluorine coating or the like can be used. By this coating treatment, it is possible to obtain an effect of extending the life of the mold by improving the mold surface hardness.

The material of the embossed carrier tape prepared in the present invention is not particularly limited as long as it is a thermoplastic resin used in this type of tape. Polystyrene, ABS, polyphenylene ether, polyvinyl chloride, polyester, polycarbonate , Polyolefin resins, fluorine resins, and polymer alloys obtained by mixing two or more of these.
In addition, these resins and polymer alloys containing these resins can be applied to nonionic surfactants, cationic surfactants, anionic surfactants and other antistatic agents, conductive carbon, carbon and stainless steel, etc. It is a resin composition to which an antistatic property or conductivity is imparted by adding a conductive agent such as conductive fibers, conductive metal oxides such as tin oxide and titanium oxide, and organic conductive materials such as aniline, pyrrole and thiophene. May be.

The thickness of the resin tape used in the present invention is generally in the range of 0.05 to 0.50 mm, but in order to keep the curvature radius R of the bent portion small as described above, it is 0.2 mm or less. Is preferred. The resin tape may be a laminate of the same material or different materials. The method for producing the resin tape used in the present invention is not particularly limited, and can be performed by a generally used method. For example, the resin composition as a raw material can be extruded and processed into a sheet, and the sheet can be slit into a desired width. Further, an antistatic layer or a conductive layer can be provided by applying an antistatic agent or a conductive substance to the surface of the resin tape.

The embossed carrier tape produced by this method is formed with a pocket for accommodating a substantially rectangular parallelepiped fine component (see FIG. 4). Examples of the fine parts stored in the pocket of the embossed carrier tape include a ceramic capacitor, a resistor, and an IC chip. In the embossed carrier tape, the radius of curvature R of the portion from the surface of the pocket opening portion to the side surface of the component storage portion is bent at 50 to 120% of the sheet thickness. Since the curvature radius R is bent at 50 to 120% of the sheet thickness in the bent portion, the fine parts can be stored in a predetermined arrangement in the pocket portion, and the stored fine parts can be made difficult to move. The smaller the curvature radius R, the greater the effect. However, in the molding method of the present invention, the curvature radius R is usually 50% or more of the sheet thickness. When R exceeds 120%, it becomes difficult to store the fine parts in a predetermined arrangement, and the stored fine parts are easy to move, so that taping and mounting are difficult.

  When the component size is reduced, it is required to be stored in a predetermined arrangement because of the ease of taking out from the component storage portion. Therefore, the embossed carrier tape of the present invention is suitable for housing fine parts having a part size of 1005 (long side dimension: 1.0 mm, short side dimension: 0.5 mm) or less. Besides 1005 size, for example, 0402 size (long side dimension; 0.4 mm, short side dimension; 0.2 mm), 0603 size (long side dimension; 0.6 mm, short side dimension; 0.3 mm), etc. It is done.

  Since the embossed carrier tape described above is formed with a pocket corresponding to the shape of the fine component, the fine component can be stored in a predetermined arrangement in the pocket component storage portion. In addition, since the gap between the inner surface of the component storage part and the micro component is small, the micro component is difficult to move after storage, and even if a micro component that is difficult to displace due to vibration or impact is about to rotate, It doesn't rotate because it gets caught.

Example 1
An embossed carrier tape for 0603 size ceramic capacitor was manufactured as follows.
First, a carbon kneading type conductive PC-based sheet (thickness: 0.15 mm) as a plastic substrate was preheated to 100 ° C. with a preheating device. Next, the preheated PC-based sheet is transferred to a molding die having a molding die in which a T-shaped male mold portion having the shape shown in FIGS. 1a and 1b- (a) is provided vertically. The mold contact part of the system sheet was heated again by the heating device (hot air blow) from the opposite side of the mold (hot air temperature; 600 ° C.). After that, while vacuuming through the vacuum hole of the mold, the male mold part of the mold and the PC mold sheet are brought into close contact with each other, and the component housing part is continuously formed at 5 m / min to obtain an embossed carrier tape. It was.
The obtained embossed carrier tape has an interval between the component storage portions of 2 mm, the short side dimension A0 in the component storage portion is 0.38 mm, the depth dimension K0 is 0.40 mm, and the curvature radius of the bent portion is 0.15 mm. there were.
(Comparative Example 1)
An embossed carrier tape was obtained in the same manner as in Example 1 except that the mold shown in FIG. 3 was used. The short side dimension A0 in the component storage part of the obtained embossed carrier tape was 0.38 mm, the depth dimension K0 was 0.40 mm, and the curvature radius of the bent part was 0.19 mm.

The embossed carrier tapes obtained in the examples and comparative examples were evaluated as follows.
(Evaluation of mounting failure rate)
Using a mounting machine (high-speed modular type, mounting accuracy ± 0.05 mm / chip), 10,000 ceramic capacitors 0603 stored in the component storage part of the embossed carrier tape were mounted at a mounting tact of 0.10 seconds / chip. The mounting error rate at that time was obtained by the following formula. The ceramic capacitors that were not mounted were not stored in a predetermined arrangement in the component storage unit. Therefore, the mounting defect rate corresponds to the number of ceramic capacitors that were not stored in a predetermined arrangement in the component storage portion of the embossed carrier tape. The evaluation results are shown in Table 1.
(Mounting failure rate) = [(Number of ceramic capacitors not mounted) / (Number of total ceramic capacitors)] × 1000000 (ppm)

DESCRIPTION OF SYMBOLS 1 Resin tape 2 Preheating apparatus 3 Heating apparatus 4 Drum 5 Mold (male type)
6 Cooler 7 Winder 11 Side plate A
111 Side plate A groove side surface 112 Side plate A groove bottom surface 12 Side plate B
121 Side plate B groove side surface 122 Side plate B groove bottom surface 13 Mold 131 Mold head 132 Mold foot 133 Mold foot width 134 Mold head back 14 Vacuum hole 21 Side plate A
211 Side plate A groove side surface 212 Side plate A groove bottom surface 22 Side plate B
221 Side plate B groove side surface 222 Side plate B groove bottom surface 23 Mold 24 Vacuum hole

Claims (2)

It consists of a side plate A (11), a mold (13), and a side plate B (12), and has the following requirements a to d. The both side plates (11, 12) and the mold (13) are rings. a shape, a rotary male vacuum mold of the embossed carrier tape.
(A) Molding to form a male mold on the groove side surface (111) and the groove bottom surface (112) of the side plate A, and the central portion of the groove formed by the groove side surface (121) and the groove bottom surface (122) of the side plate B Has mold (13).
(B) A plurality of mold heads (131) are formed on the mold foot (132) with a width larger than the width (133) of the mold feet, and the head from the mold foot (132). The cross-sectional shape of the part corresponding to the part (131) is T-shaped.
(C) A vacuum hole (14) is provided on the mating surface between the side plates (11, 12) and the mold (13).
(D) There is a gap between the back surface (134) of the mold head and the bottom surfaces of both side plate grooves (112, 122). By using a mold of the mounting serial to claim 1, a method for producing the embossed carrier tape to the mold of the forming die head (131) into close contact with a portion of the resin tape, resin tape forming die head ( 131) After heating the part in contact with the tape, the heated resin tape is evacuated from the vacuum hole (14) and drawn around the mold head (131) to form an embossed portion of the embossed carrier tape. to, rotary male vacuum forming method of the embossed carrier tape.

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