JPH0435320B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sheet punching die, and is particularly suitable for use in forming through holes in alumina green sheets for multilayer wiring boards, but it is of course applicable to other sheets as well. The present invention relates to a sheet punching die that can also be applied to punching.

Conventional configurations and their problems In recent years, with the development of microelectronics, high wiring density has been required for boards on which highly integrated components such as LSIs are mounted, and the number of wiring layers has increased, so-called multilayer wiring boards. It has been realized as Some multilayer wiring boards are made of resin or alumina, but in particular, tungsten paste is screen printed on an alumina green sheet made of alumina particles and an organic binder, which is laminated and then fired. Alumina multilayer wiring boards manufactured using this method are attracting attention. In this multilayer wiring board, a through hole is formed in the alumina green sheet for the purpose of interconnecting the wiring in each layer, and the through hole is filled with tungsten paste. Therefore, a large number of through holes, so-called through holes, are formed in a sheet for a multilayer wiring board, and the denser the wiring, the stricter the precision of the through holes is required.

Conventionally, a mold configured as shown in FIG. 1 has been used to punch through holes in such sheets. In other words, 1 is an upper plate material, 2 is a pin holding member, 3 is a pin, 4 is a stripper, and 5 is a receiving mold.As a method of fixing the pin 3 to the pin holding member 2, a head is attached to the pin 3 to prevent it from coming off. 3a and then grinding a corresponding hole in the pin holding member 2. Therefore, if the positions of the through holes you want to punch are close to each other, pin 3
The heads 3a of the pins may interfere with each other, and the approach distance of the punched through hole is limited by the diameter of the pin head 3a. Therefore, it is currently impossible to form small punched through holes with high density. In addition, the tip surface of the pin 3 is similar to the stripper 4 when no load is applied.
It is necessary to be in the same plane as the lower surface of the pin 3, but in this structure, it is necessary to precisely process the length of the pin 3 in advance. In this way, the mold manufacturing process is complicated and expensive due to the need to increase the processing accuracy of the pin 3 and the need for complicated grinding to ensure that the pin 3 just fits into the pin holding member 2. There was a problem. Furthermore, there is a structural limit to the density of the pin arrangement, and a basic problem has arisen in that it cannot be used as a mold for processing wiring boards that will become increasingly dense in the future.

OBJECTS OF THE INVENTION The object of the present invention is to provide a sheet punching die that can form through holes in a sheet with high density, has a simple manufacturing process, and can be obtained at low cost.

Structure of the Invention In order to achieve this object, the present invention provides a pin holding member which has a recess formed on the upper side leaving a peripheral portion and a through hole penetrating the recess on the lower side. At the same time, a notch is provided in the portion of the pin located in the recess to prevent the pin from coming off from the cutting edge side, and the recess is filled with a synthetic resin or solder filling material. , an upper plate material to which the upper mold is fixed with its upper surface in contact with each other, a stripper provided with a through hole through which the pin is guided, and a rubber interposed between the upper plate material and the stripper. It consists of a member and a receiving mold having a through hole corresponding to the through hole of the stripper, and the gap between the pins is prevented by preventing the pin from coming off with a filler made of synthetic resin or solder in the notch of the pin in the upper mold. To provide a sheet punching die which can reduce the distance between the two and facilitate pin fixing work.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. 11 is an upper plate material, 12 is a pin holding member,
13 is a pin, 14 is a stripper, and 15 is a receiving mold. As shown in FIG. A through hole 17 penetrating the recess 16 is provided in the shape and position. On the other hand, the pin 13 passes through the through hole 17 and its upper part is in the recess 1.
6, and a notch 18 is formed in the upper part thereof. The purpose of this notch 18 is to prevent the pin 13 from coming off, and one or more notches may be formed depending on the nature of the sheet to be punched. Reference numeral 19 denotes a hardening filler such as synthetic resin or solder that is filled in the recess 16 and fixes the upper part of the pin 13 to the pin holding member 12. Further, the notch portion 18 increases the bonding strength between the curable filler 19 and the pin 13. An upper mold 20 consisting of a pin holding member 12, a pin 13, and a curable filler 19 is attached to the upper plate material 1.
1, and this upper plate material 11 and the stripper 14, which is provided with a through hole 21 through which the pin 13 is guided, are integrally connected via an elastic body made of a rubber member 22. has been done. The upper plate material 11 and the stripper 14 are connected by a bar material 23 passing through the vicinity of their sides,
This is accomplished by E-rings or C-rings 24 fixed to both ends of this rod 23 so as to engage with the upper plate 11 and the stripper 14, respectively. In this assembled state, there is a gap greater than the thickness of the sheet to be punched between the lower surface of the pin holding member 12 and the upper surface of the stripper 14. Also, pin 13
The tip end surface of the stripper 14 and the lower surface of the stripper 14 are surface-ground to be flush with each other in the assembled state. By performing the surface grinding process in the assembled state in this way, there is no need to particularly question the machining accuracy in the length direction of the pin 13, and the mold manufacturing process can be simplified. The receiving mold 15 has a through hole 21 for the stripper 14.
A through-hole 25 is provided whose diameter and position coincide with that of the pin 13 and the through-hole 25 of the receiving mold 15, thereby enabling precise punching of the sheet. 26, 27
are mounting recesses for the rubber member 22 provided in the upper plate material 11 and the stripper 14, respectively;
It is formed wider than 2. Note that the shape of the pin 13, that is, the shape and size of the punching, can be arbitrarily selected, and various punching can be performed.

In such a sheet punching die, when punching a sheet, the sheet is placed between the stripper 15 and the receiving die 15, and by applying a load downward from the top of the die, the rubber member 22 is is deformed and pin 1
3 is the through hole 25 of the receiving mold 15 after punching the sheet.
penetrate into The deformation of the rubber member 22 which is deformed and expanded in the lateral direction is absorbed within the wide mounting recess 26. Next, after punching is completed, by removing the load from the mold, the pin 13 returns to its original position due to the repulsive force of the rubber member 22.

Effects of the Invention According to the sheet punching die of the present invention, as is clear from the above description, the upper part of the pin is inserted into the recess of the pin holding member, a notch is provided in the upper part of the pin, and the recess is Since the inside is filled with synthetic resin or solder filler, there is no need to provide a head to prevent the pins from falling out, and the distance between the pins can be made extremely close, allowing for high-density and close punching. It's easy to do. In addition, the pins can be reliably prevented from falling out by using the notch and the filler made of synthetic resin or solder, and the processing of the pins and pin holding members is extremely simple.Furthermore, since the pins do not have heads, they can be easily removed after assembly. By grinding the tip end surface of the pin and the lower surface of the stripper, there is no problem with the machining accuracy in the longitudinal direction of the pin itself, and the machining becomes extremely simple. Therefore, it is possible to provide a sheet punching mold that can punch out sheets with high precision, is easy to manufacture, and is inexpensive.

[Brief explanation of drawings]

Fig. 1 shows a conventional example, a is a longitudinal sectional view, b is a perspective view of a pin, and Fig. 2 shows an embodiment of the present invention, a is a longitudinal sectional view, and b is a perspective view of a pin and a pin holding member. Figures c and d are front views of the pins, respectively. 11... Upper plate material, 12... Pin holding member, 1
3... Pin, 14... and stripper, 15... Receiving mold, 16... Recess, 17... Through hole, 18...
Notch portion, 19...Filling material made of synthetic resin or solder, 20... Upper mold, 21... Through hole, 2
2...Rubber member (elastic body), 25...Through hole.

Claims (1)

[Claims] 1 A pin is passed through the through hole of a pin holding member, which has a recess formed on the upper side leaving a peripheral part and a through hole penetrating the recess on the lower side, and a portion of the pin located inside the recess. an upper mold having a notch and filling the recess with a filler such as synthetic resin or solder; an upper plate member having the upper mold fixed with its upper surface in contact; and the pin being guided. A sheet punching die comprising a stripper provided with a through hole passing through the stripper, a rubber member interposed between the upper plate material and the stripper, and a receiving die having a through hole corresponding to the through hole of the stripper. Type.