JP3587625B2 - Lead molding equipment for semiconductor devices - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a semiconductor device lead forming apparatus using a sector punch.
[0002]
[Prior art]
FIG. 2 shows a main part of a conventional apparatus for bending a lead by using a sector punch in a lead forming apparatus for a semiconductor device. Reference numeral 10 denotes a semiconductor device as a workpiece, 12 denotes a die supporting the semiconductor device 10, and 14 denotes a knockout which clamps and supports a lead base of the semiconductor device 10 with the die 12.
Reference numeral 16 denotes a sector punch for bending a lead into a predetermined shape with the die 12. When bending the leads, the sector punch 16 is pushed down by the punch plate 18 and descends, pushing down the leads from above, and bending the leads by striking the leads along the outer surface of the die 12.
[0003]
The sector punch 16 is rotatably supported around a support shaft 16a. When the lead is bent, the sector punch 16 is rotated so as to bring the tip of the punch inward, so that the lead can be reliably moved along the outer surface of the die 12. So that it can be bent. That is, while the sector punch 16 is lowered together with the punch plate 18, the lead is formed by bending the leading end of the sector punch 16 inward.
[0004]
A mechanism for rotating the sector punch 16 in such a manner when the lead is bent is formed by a cam surface 20 provided at the base of the knockout 14 and a roller 22 abutting on the cam surface 20.
FIG. 2 shows a state in which the sector punch 16 is in the upper position in the left half of the center line, and a state in which the sector punch 16 is lowered in the right half of the center line to bend the lead. As shown in the drawing, when the sector punch 16 is in the upper position, the roller 22 contacts the upper portion of the cam surface 20, and when the sector punch 16 is in the lower position, the roller 22 contacts the lower portion of the cam surface 20.
[0005]
The sector punch 16 moves relative to the knockout 14. This is because the knockout 14 descends together with the punch plate 18 to clamp the semiconductor device 10 with the die 12, and then moves when the punch plate 18 further descends. Action. Since the knockout 14 is stationary with the semiconductor device 10 clamped between the die 12, when the punch plate 18 further descends from this state, the sector punch 16 descends relative to the knockout 14 and the roller 22 Comes to the bottom of the cam surface 20. Since the lower part of the cam surface 20 is formed in an arcuate surface that protrudes outward, when the roller 22 climbs up on the lower part of the cam surface 20, the base side of the sector punch 16 is displaced outward, thereby supporting the support shaft. The tip side of the sector punch 16 pivots inward about the fulcrum 16a.
[0006]
As described above, the sector punch 16 rotates about the support shaft 16a. However, in order to return the sector punch 16 to the original rotation position, springs 24 and 26 for urging the sector punch 16 are mounted in the conventional example. are doing. The spring 24 is a spring provided below the support shaft 16a, and is mounted so as to repel between the inner surfaces of the sector punches 16 on both sides. The spring 26 is mounted by biasing the outer surface of the sector punch 16 with a spring provided above the support shaft 16a. By urging the leading end of the sector punch 16 to open, the sector punch 16 can be opened and closed to bend the lead.
[0007]
[Problems to be solved by the invention]
The above-mentioned springs 24 and 26 are springs for biasing the leading end of the sector punch 16 so as to be widened, and one of them is mounted in an actual device. Normally, when sufficient space for arranging the spring is provided due to the device configuration, a method of pressing the outer surface of the sector punch 16 like the spring 26 is adopted, and when the space for arranging the spring is not sufficient. In this case, like the spring 24, it is arranged inside the sector punch 16.
[0008]
However, with the conventional spring mounting method, when removing the sector punch 16 for maintenance or the like, there is a problem that the springs 24 and 26 are difficult to remove, and the springs pop out at the time of removal. Further, the roller 22 needs to be always in contact with the cam surface 20, but the conventional method cannot set the mounting position of the springs 24 and 26 to a position deviated so much from the support shaft 16a. There is a problem in that the urging force for moving does not work effectively, resulting in malfunction.
[0009]
Accordingly, the present invention has been made to solve such a problem, and an object of the present invention is to make it possible to configure a compact lead forming device for a semiconductor device and to remove a sector punch. An object of the present invention is to provide a lead forming apparatus for a semiconductor device which facilitates maintenance work and ensures operation of a sector punch.
[0010]
[Means for Solving the Problems]
The present invention has the following configuration to achieve the above object.
That is, the relative position between the die and the knockout that clamps and supports the base of the lead of the semiconductor device and the punch plate is fixed, and the punch that is rotatable by the support shaft and moves up and down together with the punch plate to contact the lead is formed. And a sector punch having a roller abutting a cam surface provided on a side surface of the knockout disposed on the other side of the support shaft with respect to a side of the knockout, and the workpiece is supported by the die and the knockout. By moving the rollers on the cam surface when the sector punch moves, the sector punch is turned around the support shaft as a fulcrum so that the punch side approaches the side surface of the die, and the lead is bent. in lead forming apparatus for a semiconductor device to be molded, set the contact projection on an end portion of the sector punch , Between the abutment projections and the punch plate, characterized in that the rollers provided with biasing means for always urged in contact orientation with the cam surface.
Further, the torsion spring is mounted before Symbol punch plate, extending the elastic piece of the torsion spring from said punch plate towards the contact projection, it abuts the elastic Hatsuhen the abutting projection It is characterized by.
Further, the tip of the knockout is formed as a separate component from the body of the knockout, and the tip of the knockout is detachably attached to the body of the knockout.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described.
FIG. 1 is a sectional view showing one embodiment of a lead forming apparatus for a semiconductor device according to the present invention. In this embodiment, similarly to the conventional apparatus shown in FIG. 2, the sector punch 16 is rotatably supported by the support shaft 16a, and the sector punch 16 is formed by bending so that the front end side of the sector punch 16 is brought closer to the outer surface of the die 12. .
[0012]
The method of clamping the lead base of the semiconductor device 10 by the knockout 14 and the die 12 and abutting the lead against the outer surface of the die 12 by the sector punch 16 to bend and form into a predetermined shape is the same as the above-described conventional method. It is. FIG. 1 shows a state before the lead is bent to the left half of the center line, and a state in which the lead is abutted against the outer surface of the die 12 and bent to the right half of the center line.
[0013]
As in the conventional example, the sector punch 16 is urged and supported such that the leading end for bending the lead opens, that is, the roller 22 is always in contact with the cam surface 20. In the present embodiment, as a method of biasing and supporting the sector punch 16, a contact protrusion 16 b is provided on the upper end of the sector punch 16, and extends from a torsion spring 30 attached to the punch plate 18 on the side surface of the contact protrusion 16 b. The structure in which the resilient pieces 30a are brought into contact with each other is adopted.
[0014]
The resilient piece 30a contacts the contact protrusion 16b and urges the roller 22 attached to the sector punch 16 in a direction in which the roller 22 always contacts the cam surface 20.
The biasing force of the resilient piece 30a acts in a direction for rotating the sector punch 16 with the support shaft 16a as a fulcrum, whereby the roller 22 always contacts the cam surface 20. Since the sector punch 16 moves up and down together with the punch plate 18, the relative position between the sector punch 16 and the punch plate 18 does not change, and the biasing force of the torsion spring 30 always acts on the sector punch 16.
[0015]
In the embodiment, the torsion spring 30 is mounted on the pin 32 provided on the punch plate 18 through the ring portion of the spring, and the fixed-side resilient piece 30b is locked so that the urging force of the resilient piece 30a acts on the sector punch 16. I am trying to do it. Of course, the method of mounting the torsion spring 30 on the punch plate 18 is not limited to this embodiment. Further, it is also possible to employ a structure in which the roller 22 is always in contact with the cam surface 20 by using the urging force of the tension spring instead of using the elastic spring.
As described above, the present invention is characterized in that the urging means for constantly bringing the roller 22 of the sector punch 16 into contact with the cam surface 20 is provided between the end of the sector punch 16 and the punch plate 18.
[0016]
A resilient piece 30a of the torsion spring 30 extends downward from the punch plate 18 and abuts against a contact projection 16b of the sector punch 16. As described above, the method of providing the urging means for connecting the punch plate 18 and the upper end of the sector punch 16 is performed by attaching a spring to the outer surface or the inner surface of the sector punch 16 as in the conventional example. As compared with the method, there is an advantage that no extra space for mounting the spring is required, and the apparatus can be formed compact.
[0017]
In a lead forming machine for a semiconductor device, a lead is bent into a predetermined shape in a plurality of steps. Therefore, the forming machine is provided with a plurality of processing stages corresponding to these processing steps. Therefore, the configuration of the processing apparatus is often restricted due to the arrangement of the processing stages adjacent to each other, and in such a case, it is extremely advantageous to be able to form the apparatus compact.
[0018]
Further, in the method of urging the sector punch 16 by bringing the resilient piece 30a into contact with the upper end of the sector punch 16 as in the present embodiment, the urging force acts on the sector punch 16 at a position farthest from the support shaft 16a. Therefore, there is also an advantage that the urging force effectively acts on the sector punch 16 and the sector punch 16 can be reliably operated.
[0019]
In the embodiment, since the torsion spring 30 is mounted on the punch plate 18, it is not necessary to consider mounting the spring on the knockout 14, and the tip 14 a of the knockout 14 a can be detachably attached to the main body of the knockout 14. Was configured. The tip 14a is detached by the screw 15.
When processing is performed many times by the sector punch 16, the plating applied to the lead is rubbed, and the plating adheres to the tip of the punch. If the plating adheres to the punch, the bending accuracy of the lead is adversely affected, so the plating needs to be removed. In this embodiment, it is possible to remove the plating from the tip of the sector punch 16 by removing the tip 14a, and there is an advantage that such maintenance can be easily performed.
[0020]
The lead forming method using the sector punch 16 is frequently used for lead forming of a semiconductor device of a type in which leads extend in all directions. However, this forming method is similar to lead forming of a semiconductor device in which leads extend in two directions. Can be applied to
[0021]
【The invention's effect】
The lead forming device for a semiconductor device according to the present invention can be made compact by being configured as described above, and can be easily incorporated into a lead forming machine having a plurality of processing stages. Further, the urging force acts effectively on the sector punch, and the malfunction of the sector punch can be eliminated. In addition, it is possible to easily remove the sector punch at the time of maintenance. Further, in the case where the tip portion of the knockout is made detachable, there is a remarkable effect that the maintenance of the punch portion of the sector punch can be facilitated.
[Brief description of the drawings]
FIG. 1 is a sectional view showing an embodiment of a lead bending device for a semiconductor device according to the present invention.
FIG. 2 is a cross-sectional view showing a configuration of a conventional example of a lead bending device for a semiconductor device.
[Explanation of symbols]
Reference Signs List 10 semiconductor device 12 die 14 knockout 14a tip 16 sector punch 16a support shaft 16b contact projection 18 punch plate 20 cam surface 22 rollers 24, 26 spring 30 torsion spring 30a spring piece

Claims (3)

A die and a knockout for clamping and supporting a base of a lead of a semiconductor device;
With the relative position with respect to the punch plate unchanged, it is rotatable by the support shaft and moves up and down together with the punch plate , and is disposed on the other side sandwiching the support shaft with respect to the punch side contacting the lead and provided on the side surface of the knockout A sector punch having a roller contacting the cam surface,
In a state where the workpiece is supported by the die and the knockout, the roller moves on the cam surface when the sector punch moves with respect to the knockout, so that the punch side of the die has the support shaft as a fulcrum. In a semiconductor device lead forming apparatus for bending a lead by rotating a sector punch in a direction approaching the side surface,
An abutting projection is provided at an end of the sector punch, and an urging means is provided between the punch plate and the abutting projection to constantly urge the roller in a direction of abutting on the cam surface. Semiconductor device lead forming apparatus. A torsion spring is mounted on the punch plate, an elastic piece of the torsion spring is extended from the punch plate toward the contact projection, and the elastic piece contacts the contact projection. The semiconductor device lead forming apparatus according to claim 1. 3. The lead molding apparatus for a semiconductor device according to claim 1 , wherein the tip of the knockout is formed as a separate component from the body of the knockout, and the tip of the knockout is detachable from the body of the knockout .

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