JPH03169055A - Lead cutting and shaping metal die - Google Patents

Abstract

PURPOSE:To obtain a lead cutting and shaping metal die which does not cause a flaw, a cut and the like on a package and on a lead of a semiconductor device by a method wherein the lead is bent and shaped by actions of a compressive force of a pressing spring and a cam lever. CONSTITUTION:A cutting die 10 as a lower metal die and a punch guide 2 as an upper metal die are opened; a lead 11 supporting a semiconductor device is placed on the cutting die 10; a cutting punch 6 and a shaping die 7a are raised and cut the lead 11 to a prescribed length. Then, the die 7a is raised further, and pushes up a package 14; the package 14 is sandwiched and fixed between the die 7a and a pressure holder 9a by using a preloaded spring 15. In nearly parallel with this action, a shaping punch 1 is lowered in an oblique direction by an action of a cam lever 5; the tip of the punch 1 pushes down the lead 11 from a point A to a point B, and shapes it. A pressing force at this time is adjusted by using a pressing spring 4; a stopper 8 acts in such a way that the shaping punch 1 does not exert at unnecessary force on the lead 11. Thereby, a flaw is not caused at the lead 11 and a cut is not produced at the package 14 by a tensile force.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a lead cutting mold for cutting the leads of a semiconductor device into predetermined dimensions and molding the leads in a semiconductor device manufacturing process.

[Conventional technology]

FIGS. 4 and 5 are sectional views of main parts for explaining an example of a conventional lead cutting mold.

As shown in FIGS. 4 and 5, this lead cutting mold includes a molding die 7 that holds the outer body 14 of the semiconductor device and molds the leads 11, and a molding die 7 that wraps the molding die 7 and molds the leads 11. A cutting die 1o that cuts, a holder 14 that faces the cutting die and presses and holds the lead 11, and a punch 12 that is located inside the holder 14 and bends the lead.
A presser punch 9 is located inside this punch 12 and is pressed by a spring 13 to press and hold the outer body 14.
It is composed of.

When cutting and molding the leads of a semiconductor device using this lead cutting mold, first, as shown in FIG. 4, the semiconductor device is placed on the cutting die 10 of the opened mold. Next, the upper die is lowered, and the lead 1 is attached to the holder 14 and the cutting die 10.
The outer body 14 is fitted into the recess of the presser punch 9 and held. Next, as shown in FIG. 5, the punch 12 and the presser punch 9 are further lowered, and the outer shell l4 is fitted into the recess of the shaped die 7, and the lead 11 is cut by the outer waves of the punch 12. 11 is bent and formed by a punch 12 and the tip of a certain-shaped die 7. Next, the upper die is raised, the leads 11 are cut, and the bent semiconductor device is removed from the die. Leads of semiconductor devices are cut and shaped by repeating such operations.

[Problem to be solved by the invention]

In the conventional lead cutting or shaping method described above, in order to cut and shape the lead to a predetermined length, it is necessary to lower the punch to a position close to the outer body of the semiconductor device. If the outer body of the semiconductor device is misaligned with respect to the punch, the outer body itself may be damaged, or the lead surface may be scraped when descending perpendicularly to the leads of the semiconductor device and cutting or bending them. However, there are disadvantages in that a tensile force is generated on the lead, the lead is scratched, or the lead protruding portion of the outer shell is missing. For this reason, the moisture resistance of semiconductor devices, etc.
It also adversely affects soldering performance when mounted on a printed circuit board.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate such drawbacks and to provide a lead cutting mold that does not cause scratches, chips, etc. on the outer body or leads of a semiconductor device.

[Means to solve the problem]

The lead cutting or shaping mold of the present invention includes a punch guide and a cutting die that sandwich and fix the leads of a semiconductor device, and the leads are fitted into the cutting die and moved in one direction to cut the leads to a predetermined length. A cutting punch for cutting, a molding die that is fitted inside the cutting punch and moves the outer shell of the semiconductor device in the same direction as the one direction, and a presser holder that receives the outer shell moved by the molding die. and a forming punch that is fitted into the sliding portion of the punch guide and moves at a predetermined oblique angle with respect to the moving direction of the presser holder and the cutting punch, thereby bending the lead after cutting downward. are doing.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a sectional view of the main parts of a word cutting or shaping mold showing one embodiment of the present invention. In this drawing, the left half shows the state of the mold immediately after the lead is cut, and the right half shows the state of the mold immediately after the lead is cut.
This shows the state of the mold when the lead is bent. FIG. 2 is a partially enlarged view for explaining the operation of the lead cutting or shaping die shown in FIG. 1. As shown in FIG. 1, this lead cutting mold includes a punch guide 2 and a cutting die 10 that sandwich and hold a lead 11, and a cutting die that is fitted into the inside of the cutting die 10 and rises to cut the lead 11. A punch 6, a shaped die 7a that is fitted into the inside of the cutting punch 6 and protrudes from the cutting punch 6 to push up the outer shell l4, and a preload spring 15 that receives the outer shell l4 pushed up from the molding die 7a. a presser holder 9a that presses with a constant pressure, and a forming punch that slides on a diagonally guided guide part of the punch guide 2 and bends and shapes the lead 11 by the compression force of the press spring 4 and the cam handle 5. 1
It is composed of

Next, the operation of cutting and molding the leads of a semiconductor device using this lead cutting mold will be described.

First, as shown in the -left half of FIG. Next, the cutting punch 6 and the molding die 7a are both raised in the direction shown by the arrow to cut the lead 11 into a predetermined length. next,
As shown in the right half of FIG. 1 and FIG.
The outer body 14 is clamped and fixed between the molding die 7a and the presser holder 9a with a compression force of 5. Almost parallel to this operation, the cam reper 5 operates to lower the shaped punch 1 in an oblique direction, for example, at an angle of 60'' with respect to the straight line, and the shaped punch 1
The tip of the lead 11 is pressed down from point A to point B to form the lead. The pressing force at this time is adjusted by the pressing spring 4. Further, the stopper 8 prevents the shaping punch 1 from applying unnecessary pressing force to the lead 11.

In this way, when molding the lead 11 with the molding bolt l, there is no misalignment between the pressing points A and B during the descent from point A to point B. 1, there is no slippage, and no unnecessary tensile force is generated on the lead. Therefore, the leads 11 are free from scratches, and the protruding portions of the leads 11 of the outer body 14 are not chipped due to tensile force. Note that from the time when the lead wire 1 first contacts the forming punch 1 to the time when it is bent to point A, the pressing force is small, and even if slippage occurs, the lead will not be damaged.
It does not generate any tensile force.

FIG. 3 is a sectional view of the main parts of a lead cutting mold showing another embodiment of the present invention. This lead cutting mold is
This is a mold for cutting and bending the leads of two semiconductor devices. As shown in the figure, this lead cutting mold has two cutting punches 6a and 6b and two forming dies 7b and 7c provided on a common cutting die 10a, and the two are arranged in a comb shape so that their tips do not interfere with each other. This is because molded punches 1a and 1b whose tips are divided are provided. Of course, the certain-shaped punches 1a and lb slide on the diagonal guide portion of the common punch guide 2a, descend in the direction of the arrow, and form the respective leads 11.

Note that the structure of the component parts not shown in this figure is the same as in the embodiment shown above. In this example, compared to the previous example, the leads of two semiconductor devices are cut at a time.
Since it is bent and formed, it has the advantage of further improving productivity.

〔Effect of the invention〕

As explained above, in the present invention, a semiconductor device that has been cut into leads of specified dimensions is pushed up by a molding die that also serves as a cutting punch guide, so that the leads are bent to a certain amount of angle, and the semiconductor device is bent at an angle preset by the punch guide. By providing a molding punch that slides and bends the lead, molding can be performed without slipping or friction between the lead surface and the tip of the molding punch. Therefore, it is possible to create a lead cutting or shaping mold that prevents damage to the plating surface applied to the lead surface, reduces the tensile force acting on the lead, and does not cause scratches on the lead or chips in the outer shell due to the tensile force. There is an effect that can be obtained.

[Brief explanation of the drawing]

1 is a sectional view of the main parts of a lead cutting mold showing an embodiment of the present invention, FIG. 2 is a partially enlarged view for explaining the operation of the lead cutting mold of FIG. 1, and FIG. FIG. 3 is a cross-sectional view of the main part of a lead cutting mold according to another embodiment of the present invention, and FIGS. 4 and 5 are cross-sectional views of the main part showing an example of a conventional lead cutting mold. . 1, la, lb... Molding punch, 2, 2a... Punch guide, 3... Missing number, 4... Pressing spring, 5
...Cam lever, 6.6a, 6b...Cutting punch,
7.7a, 7b, 7c... Molding die, 8... Stopper, 9, 9a... Holder holder, 10.10a...
Cutting die, 11... Lead, 12... Punch, 13
... Spring, 14 ... Outer body, 15 ... Preload spring.

Claims (1)

[Claims] A punch guide and a cutting die that sandwich and fix leads of a semiconductor device, a cutting punch that is fitted inside the cutting die and moves in one direction to cut the leads to a predetermined length, and an inside of the cutting punch. a molding die that is fitted into the sliding portion of the punch guide and moves the outer shell of the semiconductor device in the same direction as the one direction; a presser holder that receives the outer shell moved by the molding die; and a presser holder that is fitted into the sliding portion of the punch guide. A mold for cutting and molding a lead, comprising: a molding punch that bends the lead after cutting downward by moving at a predetermined oblique angle with respect to the moving direction of the holding holder and the cutting punch.