JP2003094388A - Punching mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a punching mold capable of providing a multiplicity of high precision holes in a carrier tape in a single punching action and of continuing the process for a long time at a high speed. SOLUTION: The punching mold for providing sprocket holes in a carrier tape is characterized in that the female die for a pitch is divided into multiple units.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a punching die. More specifically, the present invention relates to a punching die capable of punching a large number of feed holes in a carrier tape with a dimensional accuracy by a single punching operation and capable of continuing processing at high speed for a long time. .

[0002]

2. Description of the Related Art The surface mounting of electronic parts is progressing due to the rationalization of production and the production of small lots and various kinds of products, and a plastic embossed carrier tape has been attracting attention as a packaging form applied to this. As shown in FIG. 1, a strip-shaped sheet 1 is used as a carrier tape for storing various electronic parts such as semiconductors and fine parts such as precision equipment parts.
The storage recesses 2 are formed at equal intervals in the longitudinal direction, and the feed holes 3
After being perforated at equal intervals and storing parts in the storage recess,
The cover material 4 is used after being sealed. FIG. 2 is a schematic view of an example of a carrier tape manufacturing apparatus. In the carrier tape manufacturing apparatus, the strip-shaped sheet 5 is unwound from the unwinding roll 6, and is pitch-transferred by the fixed chucks 7 and 8 and the movable chucks 9 and 10 with a length corresponding to the entire length of the mold as one pitch. The strip-shaped sheet is heated to a molding temperature by a pair of upper and lower hot plates 11, pitch-transferred into a molding die 12, and a storage recess is formed by thermoforming.
In a punching die including a male die 13 having punch pins and a female die 14 having holes, feed holes are punched and finally wound up by a take-up roll 15. Figure 3
[Fig. 4] is a perspective view of an example of a female die of a conventional punching die. The female die 14 is also called a lower die and is fixed below the punching die, and has a feed hole portion 16 for a feed hole and a concave portion 17 in the shape of a concave portion for accommodating a carrier tape. When a band-shaped sheet in which a storage recess is formed in a molding die is pitch-transferred to a punching die, it is also called an upper die,
A male die (not shown) having a thickness corresponding to the female hole and having a punch pin that fits into the female feed hole descends from above and feeds into a predetermined position on the strip-shaped sheet. Perforate. If you continue to punch the feed holes with the punching die, the band-shaped sheet thermoformed with the forming die will not be completely cooled to room temperature, but will be transferred to the punching die in a warm state. The temperature gradually rises and the female mold thermally expands. On the other hand, the male type has a small contact area with the warm strip-shaped sheet and the contact time is short, so that the temperature change does not occur as much as the female type. The effect of thermal expansion is most pronounced in the sprocket holes at both ends of the female die, causing misalignment between the male and female die, which were initially aligned correctly.
If there is misalignment between the male and female dies, accurate drilling becomes difficult and burrs are created in the feed holes, resulting in defective products.In extreme cases, the male punch pins may break and cause huge damage. It causes damage. Therefore, the number of feed holes provided in the female die is limited in order to keep the positional deviation within the allowable range with respect to the temperature change of the female die. On the other hand, in order to improve productivity and reduce costs, there is a demand for increasing the number of female feed holes so that a large number of holes can be punched in one operation of the punching die. It was

[0003]

SUMMARY OF THE INVENTION The present invention provides a carrier tape with a large number of feed holes by a single punching operation.
The present invention has been made for the purpose of providing a punching die capable of punching with high dimensional accuracy and capable of continuing processing at high speed for a long time.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a punching die can be divided into a plurality of female dies for one pitch to obtain a female die. It was found that the effect of thermal expansion of the above is absorbed by the divided individual parts, and it is possible to prevent the effect of thermal expansion from appearing strongly in the feed holes at both ends of the female die, and the present invention was completed based on this finding. Came to do. That is, the present invention provides (1) a punching die for punching feed holes of a carrier tape, wherein a female die for one pitch is divided into a plurality of punching dies,
(2) A punching die according to the first aspect, in which an air vent hole is punched in the storage recess at the same time as the feed hole, and (3) a punching die according to the first aspect, in which the female die is water-cooled. Is.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The punching die of the present invention is a punching die for punching a feed hole of a carrier tape, in which a female die for one pitch is divided into a plurality of pieces. FIG. 4 is a perspective view of one embodiment of the punching die of the present invention. In the punching die of this aspect, the female die for one pitch is divided into four, and is composed of four divided female dies 18. Each of the divided female dies has two feed holes, and eight feed holes can be punched by one operation of the punching die. The split female die is fixed and positioned on the base metal 19 on its lower surface. Even if the temperature of the split female die rises, the thermal expansion due to the temperature rise is absorbed in each split female die and does not affect the adjacent split female die. The sprocket holes on both ends do not shift significantly. FIG. 5 is a perspective view of another embodiment of the punching die of the present invention. In the punching die of this aspect, the female die for one pitch is divided into four, but the lower portion of the female die 20 is continuous and has an integral structure.

In the punching die of the present invention, an air vent hole portion can be provided on the bottom surface of the female type concave portion. Figure 6
FIG. 7 is a perspective view of another embodiment of the punching die of the present invention. In the punching die of this aspect, the air vent hole portion 21 is provided on the bottom surface of the female type recessed portion, and the male die is provided with the punch pin that fits into the female air vent hole portion. By using the punching die of this aspect, it is possible to punch the feed hole in the belt-shaped sheet and simultaneously punch the air vent hole in the bottom surface of the storage recess. By punching an air vent hole in the bottom surface of the storage recess of the carrier tape, electronic components and the like can be reliably mounted in the storage recess of the carrier tape. The punching die of the present invention has a one-pitch female die divided into a plurality of pieces, and even if the temperature of the divided female die rises, thermal expansion due to the temperature rise is absorbed in each divided female die, Since it does not affect the adjacent split female dies, the air bleed holes at both ends of the air bleed hole will not be significantly displaced.

In the punching die of the present invention, the female die can be water-cooled. The method of cooling the female die with water is not particularly limited, and for example, cooling water can be passed through by providing cooling water holes in the base metal for fixing the split female die. FIG. 7 is a perspective view of another embodiment of the punching die of the present invention. In the punching die of the present invention, the base 19 for fixing the split female die is provided with the cooling water holes 22, and the cooling water is passed through. The base metal is cooled with cooling water, and the split female die fixed to the base metal is also cooled by heat conduction with the low temperature base metal, preventing the temperature rise of the split female die and splitting due to thermal expansion. It is possible to eliminate the positional deviation of the female type feed hole and the air vent hole. The shape of the cooling water hole is not particularly limited. For example, a cooling water inlet hole and a cooling water outlet hole may be provided on one end surface of the base metal, and the cooling water passage in the base metal may be U-shaped. It is also possible to provide two cooling water holes on both end faces of the gold and to provide two linear cooling water channels in the base metal. The two linear cooling water passages can independently pass the cooling water, or one end face is connected with two cooling water holes by a pipe and the other end face is connected with the cooling water. Cooling water can be passed in a U-shape by using the inlet and the cooling water outlet.

In the punching die of the present invention, the one-pitch female die is divided into a plurality of pieces, and the thermal expansion is absorbed by each of the divided female die, so that the adjacent divided female die are not affected by the thermal expansion. Since the holes at both ends of the female die do not shift significantly, good dimensional accuracy is maintained, the number of female die holes is increased, and the number of holes to be punched by one punching die operation is increased. However, the productivity of carrier tape processing can be improved. In the conventional punching die, even if the influence of thermal expansion is reduced by means such as cooling, it is possible to precisely machine many feed holes, storage recesses, air vent holes, etc. in one female die. Had to put a lot of effort into it, and there was a limit in processing technology. Since the punching die of the present invention processes a small number of feed holes, storage recesses, air vent holes, etc. in a small split female die and fixes it to the base metal,
It can be easily manufactured. Further, in the event of damage to the female die hole or the like, the conventional punching die had to be removed and repaired or discarded as a whole, but the punching die of the present invention causes damage. Since only the split female mold needs to be removed and replaced, it is economical and has little impact on production. Since the punching die of the present invention has little or no effect of thermal expansion of the female die, it is not necessary to consider the temperature of the strip-shaped sheet that is pitch-transferred from the forming die, and the storage recess is processed by thermoforming. The strip-shaped sheet can be perforated by a punching die if cooled to the upper limit temperature for maintaining its shape, which can shorten cycle time and improve productivity by operating at high speed for a long time. .

[0009]

According to the punching die of the present invention, a large number of feed holes can be punched in a carrier tape with a high dimensional accuracy by a single punching operation, and processing is continued at high speed for a long time. be able to.

[Brief description of drawings]

FIG. 1 is a perspective view of an example of a carrier tape.

FIG. 2 is a schematic view of an example of a carrier tape manufacturing apparatus.

FIG. 3 is a perspective view of an example of a female die of a conventional punching die.

FIG. 4 is a perspective view of one embodiment of the punching die of the present invention.

FIG. 5 is a perspective view of another embodiment of the punching die of the present invention.

FIG. 6 is a perspective view of another embodiment of the punching die of the present invention.

FIG. 7 is a perspective view of another embodiment of the punching die of the present invention.

[Explanation of symbols]

1 band-shaped sheet 2 Storage recess 3 sprouting holes 4 Cover material 5 strip sheets 6 rolls 7 Fixed chuck 8 fixed chuck 9 Moving chuck 10 Moving chuck 11 hot plate 12 Mold 13 male 14 female 15 winding roll 16 Feed hole 17 recess 18 split female 19 money 20 female bottom 21 Air vent hole 22 Cooling water hole

Claims (3)

[Claims] 1. A punching die for punching a feed hole of a carrier tape, wherein a one-pitch female die is divided into a plurality of punching dies. 2. The punching die according to claim 1, wherein an air vent hole is formed in the storage recess at the same time as the feed hole. 3. The punching die according to claim 1, wherein the female die is water-cooled.