JPH0586860B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a molding technology, particularly a technology for bending a workpiece, and is used for bending a lead, which is an external terminal, in the manufacture of a semiconductor device, for example. Regarding effective techniques.

[Background technology]

Dual in line packaging (DIP)
In manufacturing semiconductor devices (hereinafter referred to as ICs), when bending the horizontally protruding leads approximately vertically downward after molding a non-hermetically sealed package, the bending roller should be bent perpendicular to the IC. bending the lead at right angles by moving the
Conceivable.

However, in this forming technology, the bending roller applies a tensile force to the lead in the direction of pulling the lead out of the package, so there is a problem that a minute gap is created between the lead and the package. was revealed by the present inventor.

An example that describes the technology for molding IC leads is the "Electronic Materials November 1981 Special Edition" published by Kogyo Research Association Co., Ltd., November 10, 1981.
Available from P170 to P175.

[Purpose of the invention]

An object of the present invention is to provide a molding technique that can prevent distortion caused by bending molding.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

In other words, a holding mold is formed by a lower mold that supports the workpiece from below at its root, and an upper mold that presses the root with the lower mold, and rotates to the bending center point of the root. The ring-shaped bending gear in which the center is located is provided with a gripping member that has a recess into which the tip of the lead engages and bends the tip of the lead by moving at the same radial position from the rotation center axis. The bending gear is supported by a plurality of support gears, and at least one of the support gears is supported by a plurality of support gears.
This is the driving gear.

〔Example〕

FIG. 1 is a schematic front view showing a molding apparatus which is an embodiment of the present invention, and FIG. 2 is a schematic front view for explaining its operation.

In this example, this molding device is a DIP type.
A lead 3 protruding horizontally from a package 2 in an ICI is bent approximately vertically at its base.

This molding device is equipped with a presser die 4 that presses the vicinity of the package 2 of the lead 3 as a workpiece, and the presser die 4 holds an upper die 5 and a lower die 6 in a substantially concave shape that are aligned in the middle with each other. We are prepared. Upper mold 5
The lower mold 6 is configured so that the root portion of the lead 3 is pressed from above and below by means of left and right pressing portions 7 and 8. The lower mold 6 is fixedly installed on the floor,
The upper mold 5 is provided so as to be driven toward and away from the lower mold 6 by a cylinder device 9 installed directly above the lower mold 6 in a substantially vertically downward direction.

Further, this forming device applies a bending force that applies a force in a direction substantially tangential to a circle whose center is substantially the center point 16 of the lead 3 to be bent, which is pressed between the holding portions 8, to the lead 3, which is the workpiece. Bending device 1 as force means
It is equipped with 0. The bending device 10 includes a pair of left and right large gears, that is, bending gears 11 formed in a ring shape, and both large gears 11 are arranged so that their center lines coincide with the extension line of the center point 16 to be bent. ing. Around the large gear 11, a plurality of small gears, that is, support gears 12, are arranged at approximately equal intervals and are rotatably engaged with each other, and the large gear 11 is rotatably supported by these small gears 12. At least one of the small gears 12 is configured as a drive gear 13 (description of the structure of the drive means is omitted), and this gear 13 drives the large gear 1.
1 is designed to be rotated back and forth over 90 degrees.
A gripping member 14 is provided to protrude radially inward at a position on the inner periphery of the large gear 11 facing the holding portion 8 , and a recess 15 is provided on the distal end surface of the gripping member 14 for gripping the distal end of the lead 3 . It has been immersed so that it can be used.

Next, the action will be explained.

As shown in Fig. 1, IC1 is attached to the lower die 6.
Set the package 2 by dropping it into the recess. As a result, the root portion of the lead 3 comes into contact with the holding portion 8 of the lower die 6. At the same time, the tip of the lead 3 is fitted into the recess 15 of the gripping member 14 to be gripped.

Next, the upper mold 5 is lowered by the cylinder device 9, and the root portion 3a of the lead 3, which is the bent portion, is clamped and fixed between the pressing portion 7 of the upper mold 5 and the pressing portion 8 of the lower mold 6. .

Thereafter, as shown in FIG. 2, when the large gear 11 is rotated in the direction of the arrow by the drive gear 13, the large gear 11 has its rotation center line aligned with the bent center point 16. , the gripping member 14 holds the tip of the lead 3 while holding the center point 16 of the lead 3.
It will move in a circular arc around . Due to this arcuate movement, the lead 3 is bent approximately perpendicularly from the base portion 3a held by the holding portions 7 and 8.

This bending of the lead 3 is performed by circular arc movement centered on the root portion 3a, which is the bent portion.
A force in a direction tangential to the circle centered around the bent portion is applied to the lead 3, and no tensile force is applied in the direction of pulling the lead out from the package 2. Therefore, no gap is generated at the boundary between the lead 3 and the package 2.

〔effect〕

(1) Tensile force is applied to the workpiece during bending by holding the bent part of the workpiece and applying a force tangential to a circle centered on the bending part. Therefore, it is possible to prevent unexpected distortion from occurring in the workpiece.

(2) By gripping a part of the workpiece away from the bent part and moving it in an arc around the bent part, a force tangential to the circle centered on the bent part is applied to the workpiece. can be strengthened.

(3) The ring-shaped bending gear is rotatably supported by a plurality of support gears, and the bending gear is rotated via the support gears by a drive means independent of the holding type drive means. Therefore, it has become possible to reliably bend the lead with a simple structure.

Although the invention made by the present inventor has been specifically explained based on Examples above, the present invention is not limited to the Examples described above, and it is understood that various changes can be made without departing from the gist of the invention. Needless to say.

For example, the pressing die for pressing the bent portion of the workpiece is not limited to the specific configuration of the embodiment described above.

[Application field]

The above explanation will mainly focus on the invention made by the present inventor, which is the application field of DIP.
Although the case where it is applied to the bending molding of type IC leads has been described, it is not limited thereto.
It can also be applied to bending the leads or pins of other ICs and electronic components, as well as lead frames, printed circuit boards, other plates, and wires.

[Brief explanation of the drawing]

FIG. 1 is a schematic front view showing a molding apparatus which is an embodiment of the present invention, and FIG. 2 is a schematic front view for explaining its operation. 1...IC, 2...Package, 3...Lead (workpiece), 4, 16...Pressure mold, 5, 17...
...Upper mold, 6,18...Lower mold, 7,8,19,20
... Holding part, 9, 21 ... Cylinder device, 10
... Bending device, 11 ... Large gear, 12 ... Small gear, 13 ... Drive gear, 14 ... Gripping member, 15
...Concavity, 16...Central point to be bent.

Claims (1)

[Scope of Claims] 1. A forming device that bends a lead protruding from the side of a workpiece, centering on a root portion of the lead, comprising: a lower die that supports the workpiece from below at the root portion; , a holding die is formed by the lower die and an upper die which presses the root portion, and the lead is attached to a ring-shaped bending gear whose rotation center axis is located at the bending center point of the root portion. A gripping member having a recess with which the tip engages and bending the tip of the lead by moving at the same radial position from the rotation center axis, rotatably supporting the bending gear, and at least one of the gripping members is connected to the drive means. A molding device comprising a plurality of connected supporting gears.