JP3522871B2 - Manufacturing method of carrier tape - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a carrier tape useful for winding and storing fine parts (hereinafter referred to as "parts") such as electronic parts and precision machine parts. It is about. 2. Description of the Related Art In recent years, mounting of components (hereinafter described as an example of electronic components) on an electronic circuit board or the like has been performed by an automatic machine such as an insert machine. Components used in such automatic machines have been provided for transportation and storage in a state of being stored and held in a carrier tape and wound up. A method has been adopted in which the carrier tape is attached to the above-mentioned automatic machine, pulled out, and components are removed from the carrier tape.
In this carrier tape, for example, as shown in FIG. 5, a long thermoplastic resin sheet (tape) is provided with a large number of embossed portions a in the longitudinal direction, and one component P is attached to each embossed portion a. What is contained is known. Each of the embossed portions a has a trapezoidal portion b at the center of the bottom surface, and a groove portion c is formed around the trapezoidal portion b. A rib d for position control projects integrally around the upper surface of the trapezoidal portion b. Is established. For this reason, the component P housed in the embossed portion a is placed on the main body (package) Pa on the trapezoidal portion b and positioned by the rib d, and the lead frame Pb is extended to the groove portion c to prevent bending or the like. The problem was prevented from occurring. The conventional carrier tape includes a rib d by heat-softening a long thermoplastic resin sheet and press-forming, vacuum forming, air-pressure forming, or vacuum-pressure forming. The entire embossed portion a is obtained by integral molding, but it is difficult to reduce the R of the rising portion e (from the upper surface of the trapezoidal portion) inside the rib d to 0.2 mm or less in relation to the molding die. . Even if this restriction is not provided, the flow of the sheet heated during molding is obstructed, so that the thickness of the sheet in this portion e becomes extremely thin,
In a severe case, the part P may be broken at this part e, thereby lowering the productivity. In addition, since the flatness of the trapezoidal part b on which the part P is placed is impaired, the part P is inclined into the embossed part a. In such a case, the component P cannot be reliably picked up at the time of mounting and the component mounting rate is reduced.
Further, since the sheet is formed along the mold in the above molding, a gap β corresponding to the thickness of the mold is generated on the back side of the sheet forming the rib d. As a result, the width W of the rib d is reduced Peripheral side surface of main body Pa of P and lead frame Pb
Since it becomes close to the gap formed by the bent portion f of
The rib d fits into this gap and is less likely to come off. This makes it difficult to take out the component P by an automatic machine, and also causes the lead frame Pb to be easily bent or the like. [0004] This problem is particularly remarkable in the case of a thin fine pitch type component in which the thickness of the main body Pa is 1.4 mm or less and the pitch of the lead frame Pb is 0.5 mm or less. When contacted, the lead frame Pb was likely to bend or the like. Further, depending on the size of the embossed portion a and the forming method, a phenomenon called “sink” in which the rib d is curved inward may occur, and the rib d may interfere with the main body Pa when the component is stored and be accurately placed on the trapezoidal portion b. Can not be stored in the lead frame Pb
But could be damaged. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method of manufacturing a carrier tape that can reliably prevent the bending of a lead frame of a component, the storage failure of a component, and the like. SUMMARY OF THE INVENTION The present invention relates to a method for manufacturing a carrier tape in which a large number of embossed portions for individually accommodating fine parts are continuously provided in the longitudinal direction. At the same time as forming the embossed portion, integrally forming a trapezoidal portion having a rounded cross-sectional rib having a void on the back side around the bottom upper surface thereof, and a trapezoidal portion of the obtained molded product. Both upper and lower surfaces are sandwiched between a trapezoidal portion male mold having an outer shape corresponding to the size of the desired rib and a trapezoidal portion female mold having an outer shape corresponding to the inner size of the lower surface of the desired trapezoidal portion, Then, the upper and lower surfaces of the bottom of the embossed portion, the male mold for the embossed portion disposed at a position separated by the thickness of the rib determined from the peripheral side surface of the male mold for the trapezoidal portion, and the female mold for the trapezoidal portion For embossed parts arranged in contact with the peripheral side It is characterized in that the rib is crushed into a plate shape by being sandwiched between the female mold. According to the manufacturing method of the present invention, after the embossed portion is integrally formed with the trapezoidal portion and the rib, the trapezoidal portion and the embossed portion are successively sandwiched by male and female molds corresponding to the respective portions. , R at the rising part inside the rib is 0.2
mm or less, it is possible to form R larger than 0.2 mm in advance at the time of the first embossed part forming, and since the flow of the heated sheet at the time of forming becomes smooth, the sheet is uniformly stretched. In addition, the strength of the embossed portion is increased, and the occurrence of molding defects is eliminated, so that the product yield is improved. In addition, by eliminating the gap β corresponding to the thickness of the mold on the back side of the rib, it is possible to form a rib with a width of 0.3 mm or less, and to force all of these processes to conform to the mold shape By doing so, it is possible to form the ribs with high precision by eliminating the dimensional variation due to the molding shrinkage. In particular, even if the gap between the main body Pa and the lead frame Pb is narrow, such as a thin fine pitch type part,
In the meantime, the ribs do not fit easily and do not easily come off. Furthermore, as described above, since the shape of the rib can be determined in the subsequent process, even if the rib has a sink, it can be corrected and the component can be securely stored without climbing on the sink It becomes. A method for manufacturing a carrier tape according to the present invention will be described below in detail with reference to FIGS.
1 is a partially enlarged perspective view of a carrier tape obtained by the method of the present invention, FIG. 2 is a longitudinal sectional view in the longitudinal direction of the tape in FIG. 1, FIG. 3 is a different embodiment of FIG.
FIGS. 2A to 2C are longitudinal sectional views in the tape longitudinal direction showing the manufacturing process of the carrier tape shown in FIG. 1 in order. In these figures, 1 is, for example, 0.3 mm thick
A carrier tape formed from a long thermoplastic resin sheet such as a polyvinyl chloride sheet 1378BHR (trade name, manufactured by Shin-Etsu Polymer Co., Ltd.), and a large number of embossed portions 2 for housing electronic components are continuously provided in the longitudinal direction. It has a structure. A flat rectangular trapezoidal portion 3 protrudes from the bottom surface of the embossed portion 2, preferably at the center thereof, around which the lead frame P
A groove portion 4 for accommodating the tip of b is formed.
On the upper surface of the trapezoidal portion 3, a rib 5 for position regulation is formed integrally therewith, and a hole 6 for component recognition is provided at the center. As shown in FIG. 2, the component P has a main body Pa on the trapezoidal portion 3 and a peripheral side surface of the main body Pa is in contact with an inner side surface of the position regulating rib 5 and a front end of the lead frame Pb is formed in a groove. It is placed on part 4 and extended. Reference numeral 7 denotes a tape running drive hole formed in one side of the carrier tape 1 in a longitudinal direction, into which teeth such as a sprocket wheel of an automatic machine (not shown) are fitted to take up and rewind the tape. Is performed. As shown in FIG. 3, the trapezoidal portion 3 may be formed with a raised bottom portion 8 at the center of the upper surface for the purpose of improving rigidity or the like. In FIG. 2, 9
Is a top tape attached to the surface of the carrier tape 1 and covers the open end of the embossed portion 2. The clearance δ between the upper surface of the main body Pa and the lower surface of the top tape 9 is preferably 10% or less of the thickness of the component P. In particular, the top tape 9 contacts the upper surface of the main body Pa, and the component P It is desirable to hold it inside to elastically hold it. In the present invention, the carrier tape 1 is manufactured by the following method. First, the embossed portion 1 is integrally formed with a long thermoplastic resin sheet simultaneously with the trapezoidal portion 3 and the rib 5 by press molding, vacuum molding, air pressure molding, vacuum pressure molding, or the like. In the conventional carrier tape with ribs, the molding of the embossed portion 2 for accommodating the component is completed by this integral molding. For example, when the rib 5 is formed so as to have the narrowest width, the gap β on the back side of the rib 5 is about 0.2 mm corresponding to the thickness of the mold, and the sheet thickness of the side portion of the rib 5 is about 0.15 mm. Therefore, the width W of the rib is 0.5 mm or more. Further, considering the flow of the material sheet during molding, the R of the inner rising portion 10 of the rib 5 should be at least 0.2 mm.
It was necessary to set it to be at least mm. However, with such a dimension setting, the periphery of the rising portion 10 is extremely thin, and the strength is reduced. In the method of the present invention, the ribs are crushed into a plate shape in the next sandwiching operation, so that the first embossed portion 2, the trapezoidal portion, and the ribs are integrally formed.
As the shape of the rib, one having a rounded cross-sectional shape having a gap β on the back side, that is, the molding dimension of the entire rib including the R of the rising portion 10 is set to be larger than the final value, specifically, It is now possible to increase the size by about 0.5 mm. [0010] A press die apparatus in which these operations are advanced.
As shown in FIG. 4, for example, as shown in FIG.
Consisted of a surrounding stripper plate 14, a male mold 18 for a trapezoidal part and a male mold 19 for an embossed part, each of which is movably assembled up and down, and a female die 13 was assembled movably up and down. The one composed of the female mold 16 for the trapezoidal part and the female mold 17 for the embossed part is used. The molded product in which the embossed portion 2, the trapezoidal portion 3, and the rib 5 are integrally formed is guided to the press mold device 11, and the flat portion around the embossed portion 2 is vertically moved by the stripper plate 14 and the die 15. It is pinched and supported from. The male mold 18 for the trapezoidal part has an outer shape corresponding to the dimension in the rib to be obtained, and the female mold 19 for the trapezoidal part has an outer shape corresponding to the inner dimension in the lower surface of the trapezoidal part. As shown in FIG. 4B, when the upper and lower surfaces of the trapezoidal portion 3 of the product are sandwiched between the male mold 18 for the trapezoidal portion and the female mold 19 for the trapezoidal portion, the rib 5 becomes the male mold for the trapezoidal portion. Pressed at the lower edge of 18, the R of the inner rising portion 10
Is reduced, and the gap β on the back side of the rib 5 is crushed.
At this time, if the lower edge portion of the male mold 18 for the trapezoidal portion is chamfered in advance, the distortion given to the rib 5 is reduced, especially when the thickness of the rib 5 is reduced during molding, so that it is impossible. It is preferable because it does not take place. On the other hand, the male mold 19 for the embossed portion is preferably located at a position where the inner peripheral side face is separated from the peripheral side face of the male mold 18 for the trapezoidal portion by the thickness of the rib 5, preferably the sheet thickness constituting the rib 5. The embossed female die 17 is disposed in contact with the peripheral side surface of the female die 16 for the trapezoidal portion. When the upper and lower surfaces of the bottom surface of the embossed portion 2 are sandwiched between the male mold 19 for the embossed portion and the female mold 17 for the embossed portion, the rib 5 is crushed into a plate shape. If the clearance is within the above-mentioned preferred range, the gap β does not remain due to the spring back of the seat, and there is no possibility that the male die 19 for the embossed portion drags the rib 5 to deform the rib 5. The rib 5 of the male mold 19 for the embossed portion
It is desirable to chamfer the lower edge portion on the side in contact with the rib in advance with an R having a size equal to or larger than the width W of the rib 5, thereby preventing the rib 5 from being dragged and deformed when sandwiched. Further, depending on the size of the trapezoidal portion 3 with respect to the embossed portion 2, there may be a case where the rib 5 of the embossed portion 2 cannot be sufficiently separated from the inner side wall. When there is a possibility that the side wall may come into contact with the side wall, a wide mold may be used as the male mold 19 for the embossed portion to correct the sink mark on the side wall. The above-described hole 7 for driving the tape running is formed by forming the embossed portion on the long thermoplastic resin sheet simultaneously with the ribs and the trapezoidal portion when the embossed portion is formed on the upper and lower surfaces of the trapezoidal portion of the obtained molded product. When sandwiching between the male mold for the trapezoidal part and the female mold for the trapezoidal part, when sandwiching the upper and lower surfaces of the embossed part between the male mold for the embossed part and the female mold for the embossed part, simultaneously with or before or after any of the steps Can be done. Similarly, a hole 6 for component recognition may be formed in the center of the upper surface of the trapezoidal portion 3. After the rib 5 is crushed into a plate shape by sandwiching the upper and lower surfaces of the bottom of the embossed portion, a stripper plate is formed.
14.Molding is completed by raising the male part 12 consisting of the male part 18 for the trapezoid part and the male part 19 for the embossed part, and then raising the female part 16 for the trapezoid part that is assembled vertically. The molded product thus obtained can be released from the die 15. The carrier tape 1 is completed by repeating the series of steps described above for one or several embossed portions. In the present embodiment, the temperature of the mold for pinching may be any number of times, but is preferably lower than the softness temperature of the material sheet. Therefore, for example, when PVC having a flexible temperature of 60 ° C. is used, the mold temperature may be adjusted to about 60 ° C. Also, in the sandwiching step, a mark can be incorporated into a mold to display a material, a name of a maker, and the like. In such a case, when the material is molded at a soft temperature or lower, a clearer display is obtained. It becomes possible. In the above-described embodiment, a vinyl chloride resin is exemplified as the thermoplastic resin forming the carrier tape 1. In addition, resins such as polystyrene, polyester-based resin, polycarbonate, and polypropylene, and kneaded carbon or the like into these resins. Further, a sheet made of such a resin in which a conductive coat is applied to the surface may be employed. According to the present invention, it is possible to effectively prevent defective storage of components, which is likely to occur when the components are stored in the embossed portion and which is caused by the lead frame riding on the ribs; Even if the components housed in the embossed part are subjected to vibrations caused by winding or transporting the tape, it is possible to prevent inconvenience such as bending of the lead frame; easily and efficiently manufacture a carrier tape from which the components can be easily taken out. Can be achieved;

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially enlarged perspective view of a carrier tape obtained by the method of the present invention. FIG. 2 is a longitudinal sectional view in the longitudinal direction of the tape in FIG. FIG. 3 is a longitudinal sectional view showing a different embodiment of FIG. 2; 4 (a) to 4 (c) are longitudinal sectional views in the longitudinal direction of the tape sequentially showing the steps of manufacturing the carrier tape shown in FIG. FIG. 5 is a longitudinal sectional view of a conventional carrier tape in a longitudinal direction. [Explanation of reference numerals] 1) Carrier tape, 2) Embossed part, 3
{Trapezoid, 4} Groove, 5} Rib, 6}
Hole (for component recognition), 7mm (for tape running drive),
8 ‥ raised part, 9 ‥ top tape, 10
‥ Inner rising part, 11 ‥ Press mold equipment, 12 ‥
Male part, 13 ‥ female part, 14 ‥ stripper plate, 15 ‥ die, 16 ‥ female part for trapezoid part, 17 ‥ female part for embossed part, male part for 18 ‥ trapezoid part, for 19 ‥ embossed part Male type, P ‥ fine parts (parts), Pa ‥ main body, Pb ‥ lead frame, β ‥ void, δ ‥ clearance.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 51/00-51/46 B65B 15/04

Claims (1)

(57) [Claim 1] In a method of manufacturing a carrier tape in which a large number of embossed portions for individually accommodating fine parts are continuously provided in a length direction, a long thermoplastic resin sheet is provided. Simultaneously with the molding of the embossed part, a trapezoidal part with a rounded cross-sectional rib having a void on the back side is integrally molded on the bottom upper surface, and the top and bottom of the trapezoidal part of the obtained molded product Both sides are sandwiched between a trapezoidal male part with an outer shape corresponding to the required size in the rib and a female part for the trapezoidal part with an outer shape corresponding to the inner dimension of the lower surface of the desired trapezoidal part. The upper and lower surfaces of the bottom of the portion, the male mold for the embossed portion and the peripheral surface of the female mold for the trapezoid portion, which are disposed at positions separated by the thickness of the rib required from the peripheral surface of the male mold for the trapezoidal portion. Between the female die for the embossed part arranged in contact with The carrier tape manufacturing method, characterized by crushing the ribs in a plate shape.