JP2552098B2 - Lead forming method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead forming method and an apparatus for forming leads which are led out from an outer casing of a semiconductor device.

[0002]

2. Description of the Related Art Generally, there are various types of semiconductor device package structures, but a dual-line type that is inexpensive and has high productivity is the mainstream. This dual in-line type semiconductor device is composed of an outer shell formed by resin-sealing an integrated circuit chip and a plurality of leads for transmitting / receiving input / output signals to / from the integrated circuit chip.

Further, the leads after resin encapsulation are in a state of being drawn out so as to extend horizontally outward from both side surfaces of the rectangular parallelepiped outer shell, and the leads can be easily bent and mounted on a circuit board in a subsequent process. Was molded as. This lead forming method has been conventionally performed with a lead forming die.

FIG. 3 is a diagram showing an example of a lead forming die, and FIGS. 4 (a) to 4 (e) are diagrams showing an operation sequence of the die for explaining a lead forming method by the lead forming die of FIG. is there. Conventionally, the lead molding die used for lead molding is
As shown in FIG. 3, an upper die 11 that moves up and down by using a guide post as a guide, a die 13 that has a recess on which a lead 17 is mounted and an outer shell of a semiconductor device is inserted, and a protrusion on which the lead 17 is mounted, Lower die 12 for attaching this die 13 and die 13
It is provided with a shedder 15 attached to the upper die 11 via a spring for holding the lead 17 placed on the plate, and punches 14a and 14b for bending the lead 17 pressed by the shedder 15.

To form the leads of the semiconductor device using this lead forming die, first, as shown in FIG. 4A, the outer shell 16 is inserted into the recess of the die 13 and the leads 17 are attached to the die 13. Place it on the protruding part of. Next, as shown in FIG. 4B, the upper die 11 is lowered and the shedder 15 is used to lead 17
Press the root of. Then, as shown in FIG. 4C, the punches 14a, 14
b is lowered and the lead 17 is bent from one end side of the root portion.

Next, as shown in FIG. 4 (d), when the upper mold 11 is further lowered and the punches 14a and 14b reach the lower dead point, the lead 17 is bent back and the tip portion is horizontally formed. It Then, as shown in FIG. 4E, the upper die 11 is lifted to expose the semiconductor device in which the leads 17 are molded. Then, the semiconductor device is removed from the die 13 by the robot arm of the transfer device.

As described above, the semiconductor devices are gripped one by one by the robot arm and placed on the die 13, and the leads 17 are molded by the vertical movement of the molding die.

[0008]

However, in the above-described conventional lead forming method, since one by one is formed intermittently, the operation of carrying the semiconductor device and removing it from the mold during one molding cycle. However, there was a limit to increasing the molding speed of the device. In addition, since a crank press machine is used to open and close the mold, noise and vibration and dust generation due to the punch-die collision that occur each time the mold is closed are large, and there is no noise in the clean semiconductor factory. Installation on the same floor will be a problem as it will affect the equipment. Further, the mold itself is larger than the product, and the press machine itself equipped with the mold is also large, and it is necessary to increase the floor area to be installed.

Therefore, it is an object of the present invention to provide a lead forming method capable of continuously forming leads of a semiconductor device and having a high forming speed and no noise or dust, and a lead forming apparatus which can be installed even if the floor area is small. Is.

[0010]

A feature of the present invention is that a plurality of leads extending horizontally outward from a side surface of an outer casing of a semiconductor device and arranged and led out in one direction are provided with a root portion having a predetermined length from the side surface. In the lead forming method, the intermediate portion is formed by bending it at a desired inclination at a position and the tip portion of the lead having a desired length is folded back and formed so as to extend horizontally. A plurality of first rollers that press the outer body in the one direction while sandwiching the root portion of the lead by a plurality of first rollers, and a plurality of second rollers that are arranged side by side at the same position as the first roller pair. A plurality of first and second roller pairs are arranged side by side in the same position as the first roller pair and the second roller pair by sandwiching the intermediate portion of the lead with a pair to gradually increase the inclination and bending to form a desired inclination. 3 roller pairs A lead formation method of molding so as to maintain the inclination of accompanying the tip horizontally when the slope of sandwiching a de of tip the intermediate section gradually changes.

Another feature of the present invention is that the outer shell of the semiconductor device before the lead molding and the inlet hole having a shape into which the leads are inserted are formed on one surface, and after the lead molding is performed on the surface opposite to the one surface. And a die body having an outlet hole of a shape in which the outer body and the lead of the semiconductor device are extruded, and the lead of the lead which is arranged and pushed from the inlet hole of the die body toward the outlet hole. The plurality of first roller pairs sandwiching the root portion are arranged so as to correspond to the same position as the first roller pair and gradually increase the inclination toward the outlet hole to obtain a desired inclination. A plurality of the second roller pairs sandwiching the intermediate portion of the lead are made to correspond to the same position as the second roller pair, and the inclination of the intermediate portion is changed by the second roller pair, and Re A third pair of rollers horizontally correct shaping the inclination of the tip portion of the de a lead forming apparatus and a pushing mechanism for pushing the said outlet hole pushes the outer body put the semiconductor device into the inlet hole.

[0012]

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

FIG. 1 is a perspective view for explaining an embodiment of the lead forming method of the present invention. As shown in FIG. 1, this lead forming method is performed by sandwiching a root portion 17a of a lead 17 with a plurality of first roller pairs composed of upper and lower rollers 1a and 1b arranged side by side in an arrow direction. Body 16
Is pushed in the direction of the arrow, and the middle portion 17b of the lead 17 is sandwiched by a plurality of second roller pairs composed of upper and lower rollers 2a and 2b arranged side by side at the same position as the first roller pair, and the inclination is gradually increased. The tip 17c of the lead 17 is clamped by a plurality of third roller pairs formed by rollers 3a and 3b arranged in the same position as the second roller pair at the same time. This is to shape the tip portion 17c so that the inclination of the tip portion 17c is kept horizontal when the inclination of the intermediate portion 17b gradually changes.

That is, this lead forming method is inspired by the extrusion forming method. The difference from the ordinary extrusion forming method is that the leads having a narrow space and a narrow width are bent by the pushing force at the time of forming. That is, a roller mechanism for molding that makes rolling contact is used so that it does not occur. In addition, the roller pair is formed by two rollers and is held by these roller pairs so that the interval between the roller pairs is made as small as possible so that each part of the lead is always sandwiched and held even when the outer body 16 is pushed and moved. . Although the distance between the roller pairs depends on the size of the leads of the semiconductor device, it is desirable that the distance be the same as the distance between the leads 17 that are led out from the outer casing 16.

FIG. 2 is a perspective view showing an embodiment of the lead forming apparatus of the present invention. As shown in FIG. 2, this lead forming apparatus includes a horizontally extending lead 17 and an outer shell 1 before forming.
A die body 4 in which an inlet hole 6 having a shape into which 6 is inserted is formed, and an outlet hole 5 having a shape into which a bent lead 17 after molding is extruded is formed on the opposite surface; A plurality of first roller pairs 1 that are arranged in parallel from the inlet hole 6 toward the outlet hole 5 and that sandwich the root portions of the leads to be pushed, and the plurality of first roller pairs 1 are made to correspond to the same positions as the first roller pairs, and the outlet holes are also provided. A plurality of second roller pairs 2 which are arranged so as to gradually increase in inclination toward a desired inclination and sandwich the intermediate portion of the lead 17, and the second roller pair 2 is made to correspond to the same position as the second roller pair 2. The third roller pair 3 which straightens and corrects the inclination of the tip portion of the lead 17 in accordance with the change in the inclination of the intermediate portion by the second roller pair 2, and the outer shell 16 is pushed into the inlet hole 6 from the outlet hole 5. The pusher 7 for pushing out is provided.

The first roller pair 1 holding the root of the lead 17 is arranged in parallel along the extrusion direction, and the third roller pair 3 holding the tip of the lead 17 is in the exit hole 5.
It is arranged so that it goes down as it goes to. On the other hand, the second that holds and holds the middle portion of the bendable lead 17
The roller pair 2 is placed so as to be gradually inclined from the horizontal, and the exit hole 5
The second roller pair in the vicinity is mounted at a desired bending angle.

Each of the rollers of the roller pair 1, 2 and 3 is fitted in a semi-circular groove of a plate member made of gun metal, and the edge portion of the semi-circular groove is caulked so that the rollers do not fall, and the edge portion is protruded. It has stopped. Then, the plate member to which these many rollers are attached is attached to each position of the dice body member divided into two parts with an adhesive, and the dice body members divided into two parts are assembled facing each other to form the die body 4.
In the case of a semiconductor device having a relatively coarse pitch and a lead width, a commercially available needle plane bearing can be used instead of the plate member on which the roller is assembled.

Next, the lead forming operation by this lead forming apparatus will be described. First, a predetermined number of semiconductor devices are mounted on a transport rail (not shown). Then, the outer body 16 of the semiconductor device at the final end is pushed and moved by the hydraulically driven pusher 7, and the semiconductor devices are sequentially pushed out from the inlet hole 6 of the die body 4 into the outlet hole 5. As a result, the lead 17 of the semiconductor device moves in the die body 4 while being sandwiched by the first roller pair, and is formed into a desired shape by the second and third roller pairs 2 and 3.

[0019]

As described above, according to the present invention, the lead can be formed into a desired shape when the semiconductor device is continuously conveyed and at the same time the lead is gradually deformed by rolling contact and the lead is completely conveyed. There is an effect that the operation of transporting the semiconductor device and the mounting operation to the mold, which are included in one molding cycle, are eliminated and the molding time is shortened accordingly. Further, since the molding can be performed by simply moving the semiconductor device, noise, vibration and dust generated by hitting the punch and the die member, which have occurred in the past, are eliminated, and there is no adverse effect on other equipment. Furthermore, the size of the apparatus main body can be reduced to the size of a conventional die and the floor area to be installed can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view for explaining an embodiment of a lead forming method of the present invention.

FIG. 2 is a perspective view showing an embodiment of the lead forming apparatus of the present invention.

FIG. 3 is a view showing an example of a lead forming die.

FIG. 4 is a view showing an operation sequence of a die for explaining a lead forming method using the lead forming die.

[Explanation of symbols]

 1 1st roller pair 1a, 1b, 2a, 2b, 3a, 3b roller 2 2nd roller pair 3 3rd roller pair 4 Dice body 5 Exit hole 6 Entrance hole 7 Pusher 11 Upper mold 12 Lower mold 13 Die 14a , 14b Punch 15 Shedder 16 Outer shell 17 Lead 17a Root part 17b Intermediate part 17c Tip part

Claims (2)

(57) [Claims] 1. A plurality of leads, which horizontally extend outward from a side surface of an outer casing of a semiconductor device and are arranged side by side in one direction, are bent with a desired inclination at a position of a root portion having a predetermined length from the side surface, and are intermediate. A lead forming method of forming a portion and bending the tip portion of the lead having a desired length so as to extend horizontally so that the lead is formed by a plurality of first roller pairs arranged side by side in the one direction. The outer body is pushed in the one direction while sandwiching the root portion of the lead, and the intermediate portion of the lead is sandwiched by a plurality of second roller pairs arranged side by side at the same position as the first roller pair. The tip of the lead is formed by a plurality of third roller pairs which are bent at a gradually increasing inclination to form a desired inclination and are arranged side by side at the same position as the first roller pair and the second roller pair. Of the middle part A lead forming method, characterized in that the lead is formed so that the inclination of the tip portion caused by the gradual change in inclination is kept horizontal. 2. The semiconductor device before the lead molding, wherein the outer casing of the semiconductor device and the lead are inserted into one surface of the inlet hole, and the surface opposite to the one surface of the semiconductor device after the lead molding. A die body in which an outer shell and an outlet hole having a shape for pushing the lead are formed, and a plurality of sandwiching the root portion of the lead that is arranged and pushed from the inlet hole of the die body toward the outlet hole. The first roller pair and the first roller pair are made to correspond to the same position as the first roller pair, the inclination is gradually increased toward the outlet hole, and the intermediate portion of the lead is arranged so as to have a desired inclination. The plurality of second roller pairs to be sandwiched are made to correspond to the same position as the second roller pair, and the tip end portion of the lead is changed in accordance with the change in the inclination of the intermediate portion due to the second roller pair. Inclination A lead forming apparatus comprising: a third roller pair for horizontally straightening and forming a die; and an extruding mechanism for inserting the semiconductor device into the inlet hole and pushing the outer shell to push out the outlet hole.