JP2000216320A - Lead molding device for semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lead molding device for a semiconductor device, wherein peeling of a solder from a lead surface, etc., at molding an outer lead to a prescribed J-shape is prevented to reduce quality related problems and improved yield. SOLUTION: A reception die 21 wherein, related to a placed semiconductor device 4, an outer lead 8 which is pre-bent and extends from an enclosure 6 is held with a curling part 22, a pressing pad 13 which presses the semiconductor device 4 on the reception die 21 from upper side to hold it, a cam die 24 which rotates around a rotational axis 23 to sandwich the pre-bent outer lead 8 of the semiconductor device 4 on the reception die 21 with the curling part 22 for it to be molded into a J-shape, and a cam punch 18, which reciprocates vertically and allows a down slope part 19 to slide an upper slope part 28 provided to the cam die 24, so that the cam die 24 is made to rotate in the cross direction, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead forming apparatus for a semiconductor device used when forming an outer lead extending from an envelope into a J-shape.

[0002]

2. Description of the Related Art The prior art will be described with reference to FIGS. FIG. 2 is a longitudinal sectional view of a main part of a conventional example, and FIG. 3 is a perspective view of a semiconductor device in which outer leads are preliminarily bent.

In FIGS. 2 and 3, reference numeral 1 denotes a press pad attached to an upper die of a lead forming apparatus, and 2 denotes a bending die attached to a lower die. Reference numeral 3 denotes a concave portion for mounting and housing the semiconductor device 4 formed on the bending die 2;
Is a curling portion formed in the concave portion 3. Then, the semiconductor device 4 placed and housed in the concave portion 3 is
An outer lead 8 extending from both side surfaces 7 and bent at an angle of approximately 90 degrees, and further having a front end portion preliminarily bent into a preliminary J shape is formed into a predetermined J-shaped outer lead 8 by the curling portion 5. You.

[0004] That is, the forming of the pre-bent outer leads 8 of the semiconductor device 4 is performed as follows. First, the lower die and the upper die are opened, and the semiconductor device 4 is placed in the concave portion 3 of the bending die 2 such that the distal end side of the outer lead 8 preliminarily bent into a pre-J shape fits in the curling portion 5. To store. Thereafter, the upper die is lowered, and the envelope 6 is pushed down by the press pad 1. The outer lead 8, which has been preliminarily bent by the pressing down, is deeply bent at the tip end side in accordance with the shape of the curling portion 5, and is formed into a predetermined J-shaped outer lead 8. Then, by raising the upper die and raising the holding pad 1, the semiconductor device 12 in which the outer lead 8 remaining in the concave portion 3 of the bending die 2 is formed in a predetermined J-shape is removed from the opened lead forming apparatus. Take out.

[0005] However, in the above prior art,
When the pre-bent outer lead 8 is formed into a predetermined shape, it is strongly pressed into the curling portion 5 of the bending die 2 so as to follow the shape and is bent deeply, so that the surface of the pre-bent outer lead 8 is excessively large. Pressing force acts.
The solder applied to the surface of the outer lead 8 preliminarily bent by the excessive pressing force is peeled off or scratched to cause quality trouble, resulting in a low yield. The solder applied to the curling portion 5 of the bending die 2 because the pre-bent outer lead 8 is pressed with a strong force adheres. Each time, the mold is cleaned to remove the attached solder. Was required, and the operation rate of the apparatus was greatly reduced.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to form an outer lead into a predetermined J-shape by applying the outer lead to the surface of the lead. It is possible to reduce the quality trouble by preventing the solder from being peeled or scratched, to improve the yield, to reduce the frequency of the mold cleaning and to increase the equipment operation rate. An object of the present invention is to provide a lead forming device for a semiconductor device.

[0007]

According to the present invention, there is provided a lead forming apparatus for a semiconductor device, which extends from an opposing side surface of an envelope and has a length of approximately 9 mm.
A receiving die for mounting a semiconductor device having an outer lead that is bent at an angle of 0 degrees and whose front end side is preliminarily bent in a preliminarily J-shape; and a preliminarily bent outer lead formed on the receiving die. A curling portion for holding the tip side portion, a press pad provided to press and hold the semiconductor device placed on the receiving die, and outer pre-bent outer sides of the semiconductor device held by the press pad. It is characterized in that it has a molding mechanism for molding into a predetermined J-shape by sandwiching the leading end side portion of the lead between the curling part and the molding mechanism. It is characterized in that it comprises two cam dies which operate in the crossing direction of the forward / backward movement so as to be sandwiched in the direction of the curling portion by the forward / backward movement of the cam punch. The cam punch and the cam die both have slopes, and the corresponding slopes are brought into sliding contact with each other, so that the cam die operates in the cross direction in response to the operation of the cam punch to perform pinching. Further, the cam die has a concave portion for forming the outer lead into a predetermined J-shape by being sandwiched between the curling portion and the two cam dies. And is constantly urged in the direction opposite to the sandwiching direction.Furthermore, the semiconductor device is held by a receiving die and a holding pad, and a cam punch and a cam die are used. The outer lead is formed in a continuous series of operations.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG. 1 which is a longitudinal sectional view of a main part and FIG. 3 which is a perspective view showing a semiconductor device in which the above-mentioned outer leads are preliminarily bent. I do.

1 and 3, reference numeral 11 denotes an upper die set constituting an upper die of a lead forming apparatus, and reference numeral 12 denotes an upper die holder attached to the upper die set 11.
Reference numeral 13 denotes a pressing pad, the lower surface of which is a pressing surface larger than the upper surface of the envelope 6 for uniformly pressing the entire upper surface of the envelope 6 of the semiconductor device 4. The holding pad 13 is attached to a lower end of a suspension bolt 15 that is vertically movably inserted into a through hole 14 formed in the upper die holder 12.

The hanging bolt 15 to which the holding pad 13 is attached
The upper end is provided with a flange 15a having a larger diameter than the through hole 14, and the upper end is constantly pressed downward by a spring 17 housed in a mounting hole 16 formed in the upper die set 11. Being energized. The range of the vertical movement of the suspension bolt 15 is as follows.
The upper pad 2 serves as a stopper that restricts the downward movement, and the press pad 13 contacts the lower surface of the upper die holder 12 to restrict the upward movement.

Reference numeral 18 denotes a cam punch fixed to the upper mold holder 12 by a pressing plate (not shown) and extending downward.
The pressing pads 13 are arranged in pairs so as to be in sliding contact with both side surfaces. Downward slopes 19 are formed at the lower portions of the cam punches 18 provided on both sides of the press pad 13 so as to extend outward from the inner side surface in sliding contact with the press pad 13 toward the lower end. .

On the other hand, reference numeral 20 denotes a lower die holder attached to a lower die set (not shown) constituting a lower die opposed to the upper die. 21 is a lower die holder 20
The semiconductor device 4 is mounted on an upper portion of the receiving die which is attached immediately below the upper press pad 13. Then, on the opposite side of the upper end of the receiving die 21,
A curling portion 22 is provided in which a plurality of pre-bent outer leads 8 extending from the side surface of the envelope 6 of the mounted semiconductor device 4 are accommodated.

Further, the lower die holder 20 has a rotating shaft 23 below the receiving die 21 and a curling portion 2 extending in the axial direction.
2 is provided so as to be parallel to the direction of the cut side. The upper cam punch 1 is mounted on the rotating shaft 23.
8, a pair of cam dies 24 are attached so as to rotate in the direction indicated by the double-headed arrow X.
Is rotated so that the receiving die 21 is sandwiched from both sides. The upper portion of the cam die 24 is constantly urged by the spring 25 in the direction indicated by the arrow Y. When both cam dies 24 rotate so as to be opened by the urging force of the spring 25, the lower portion of the cam die 24 is moved downward. The rotation range is regulated by the protrusion 26 projecting toward the lower die holder 20 coming into contact with the stopper surface 27 of the lower die holder 20.

Further, the cam die 24 is provided at its upper part with an upward slope 28 which is in sliding contact with a downward slope 19 provided below the cam punch 18, thereby lowering the cam punch 18 by lowering the cam punch 18. The upwardly inclined portion 28 slides against the 19, and the cam die 24 rotates so as to sandwich the receiving die 21 from both sides against the urging force of the spring 25. Further, a concave portion 29 corresponding to the curling portion 22 of the receiving die 21 is formed in the upper edge of the cam die 24 on the receiving die 21 side, and a receiving portion is provided between the concave portion 29 and the curling portion 22 of the receiving die 21. Die 21
The semiconductor device 4 mounted on the semiconductor device 4 is formed so as to sandwich the front end side of the pre-bent outer lead 8 so as to form a predetermined J-shaped outer lead 8.

The preformed outer lead 8 of the semiconductor device 4 is formed by the lead forming apparatus configured as described above in the following manner. That is,
First, the semiconductor device 4 is placed on the receiving die 21 with the upper and lower dies of the lead forming apparatus opened so that the tip of the outer lead 8 preliminarily bent is accommodated in the curling portion 22. Subsequently, the upper die is lowered to bring the press pad 13 into contact with the upper surface of the envelope 6 of the semiconductor device 4, and the upper die is lowered so as to further compress the spring 17, and pressed by the urging force.

When the upper die is lowered, the cam punch 18 is lowered at the same time, and the downward slope 19 of the cam punch 18 and the upward slope 28 of the cam die 24 come into sliding contact with each other.
The cam die 24 rotates so as to sandwich the receiving die 21 from both sides against the urging force of the spring 25. Then, the front end side of the pre-bent outer lead 8 of the semiconductor device 4 is sandwiched between the curling portion 22 of the receiving die 21 and the concave portion 29 of the cam die 24. Further, the outer lead 8 preliminarily bent by lowering the upper die is used for the curling portion 2.
The 2 and the concave portion 29 form a predetermined J-shaped outer lead 8.

After the outer lead 8 is formed into a predetermined J-shaped outer lead 8, the upper die is raised and the cam punch 18 is retracted upward. Accordingly, the cam die 24 in which the upward slope 28 slides on the downward slope 19 of the cam punch 18 is rotated so as to be opened by the urging force of the spring 25, and the protrusion 26 hits the stopper surface 27 and returns to the original position. At the same time, the recess 29 separates from the receiving die 21. Further, as the upper die rises, the presser pad 13
Of the semiconductor device 4 is released. Thereafter, the semiconductor device 4 having the outer lead 8 formed into a predetermined J-shape is taken out from the opened lead forming apparatus.

As described above, according to the apparatus configured as described above, the cam die 24 is formed such that the cam lead 24 is sandwiched between the pre-bent outer lead 8 and the die 21 when the lead is formed. Since the pressing force applied to the surface of the outer lead 8 is minimal and does not squeeze strongly, the solder applied to the surface of the outer lead 8 may be peeled off or damaged. It is greatly reduced. As a result, quality troubles associated with lead molding are reduced, and the yield is improved. Further, since the surface of the outer lead 8 is not pressed against the receiving die 21 or the cam die 24 with a strong force, the chance of solder adhesion is extremely reduced. No need for mold cleaning,
The equipment operation rate is greatly improved. Further, while the upper die is moved up and down once, the holding of the semiconductor device 4 by the receiving die 21 and the press pad 13 and the cam punch 1
Since the forming of the outer lead 8 by using the cam die 8 and the cam die 24 is performed by a series of continuous lead forming steps, it is not necessary to particularly increase the number of steps.

[0019]

As is apparent from the above description, according to the present invention, when the outer lead is formed into a predetermined J-shape, the possibility of peeling or flawing of the solder applied to the lead surface is reduced, In addition to the quality trouble being reduced, the yield is improved, and the frequency of cleaning the mold is reduced, so that the operation rate of the apparatus is greatly improved.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a main part of one embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of a main part of a conventional example.

FIG. 3 is a perspective view of a semiconductor device in which outer leads are preliminarily bent.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 4 ... Semiconductor device 6 ... Envelope 7 ... Side surface 8 ... Outer lead 13 ... Holding pad 18 ... Cam punch 19 ... Downward slope part 21 ... Receiving die 22 ... Curling part 23 ... Rotating shaft 24 ... Cam die 25 ... Spring 28 ... Upward Slope 29: recess

Claims (6)

[Claims] 1. An enclosure extending from opposite sides of the envelope substantially 90
A receiving die on which a semiconductor device having an outer lead bent at an angle of degrees and having a front end portion preliminarily bent in a preliminary J shape is mounted; and a preliminarily bent outer lead formed on the receiving die. A curling portion for holding a tip side portion, a holding pad provided to hold and hold the semiconductor device placed on the receiving die, and both pre-bent sides of the semiconductor device held by the holding pad A lead forming device for a semiconductor device, comprising a forming mechanism for forming a front end portion side of the outer lead between the curling portion and a predetermined J-shape. 2. A molding mechanism comprising a pair of cam punches arranged on both side surfaces of the press pad and two cam dies operating in a direction intersecting the advance / retreat operation so as to be sandwiched in a curling direction by the advance / retreat operation of the cam punch. 2. The lead forming apparatus for a semiconductor device according to claim 1, further comprising: 3. The cam punch and the cam die both have slope portions, and the corresponding slope portions are slid in contact with each other so that the cam die operates in the cross direction in response to the operation of the cam punch to pinch. 3. The lead forming apparatus for a semiconductor device according to claim 2, wherein the step is performed. 4. The lead forming apparatus for a semiconductor device according to claim 2, wherein said cam die has a concave portion for forming an outer lead into a predetermined J-shape by sandwiching said cam die with a curling portion. 5. The semiconductor according to claim 2, wherein the two cam dies are supported by the same rotation shaft, and are always urged in a direction opposite to a sandwiching direction. Equipment lead molding equipment. 6. The method according to claim 1, wherein the holding of the semiconductor device by the receiving die and the pressing pad and the forming of the outer lead by the cam punch and the cam die are performed in a continuous series of operations. 3. The lead forming apparatus for a semiconductor device according to 2.