JP2521234B2 - Method and apparatus for manufacturing lead frame for semiconductor device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of punching a lead frame for a semiconductor device having a plurality of unit patterns from a conductive long base material and an apparatus used therefor.

[0002]

2. Description of the Related Art Conventionally, a lead frame having an odd number of unit patterns is punched from a conductive long base material which is intermittently fed by a press die having a corresponding odd number of unit patterns, and a predetermined die is formed. It is formed by cutting to a predetermined length with a single fixed cutting blade that is synchronized with timing.

[0003]

In the above conventional method,
The larger the number of unit patterns formed on the lead frame, the larger and complicated the press die becomes and the more expensive it becomes.
On the other hand, if one unit pattern is punched by punching once, the production efficiency is poor. Further, if a press die that punches out two unit patterns at the same time is used, there is a problem that the feed pitch of the base material becomes two unit patterns, and it is impossible to cut every odd number of unit patterns.
Therefore, it is an object of the present invention to provide a method and apparatus for forming a lead frame having an odd number of unit patterns by using a press die that forms two unit patterns at a time.

[0004]

In the present invention, in order to solve the above-mentioned problems, the conductive long base material 10 is intermittently moved in the longitudinal direction while two adjacent ones are provided to the long base material 10. A pair of patterns 23 composed of the unit patterns 2 and 2 are sequentially arranged in the longitudinal direction and punched out. The cutting blade 12 is located on the downstream side of the press die 8 and operates in synchronization with this, and a predetermined odd number of unit patterns. Cut the long base material 10 every 2
A lead frame 1 having an odd number of unit patterns 2 is formed. The cutting blade 12 cuts the center of the pair of patterns 23 located therebelow after the long base material 10 has moved a predetermined number of times to form the lead frame 1 having an odd number of unit patterns 2. After that, the long base material 10 is 1
After moving a small number of times, the cutting blade 13 cuts the ends of the pair of patterns 23 located therebelow to form another lead frame 1 having an odd number of unit patterns 2.

In order to carry out this method, a feeding device for intermittently moving the conductive long base material 10 in the longitudinal direction and a lower surface of the punch holder 7 are attached to the long base material 10.
Has two unit pattern molds arranged in the moving direction of the long base material 10, and the punching operation is performed after the long base material 10 is moved.
In addition, a press die 8 for punching out a plurality of unit patterns 2 arranged in the longitudinal direction by sequentially punching a pair of patterns consisting of two adjacent unit patterns, and a punch holder 7 as well.
Attached to the lower surface of the press base 8 and arranged at a predetermined interval downstream of the press die 8 so as to cut the center A of the pair of patterns located below after the long base material 10 has moved a predetermined number of times. After the first cutting blade 12 and the first cutting blade 12 are operated, the long base material 10 is moved by a number of times smaller than the predetermined number of times, and then the end B of the pair of patterns located below is cut. Attached to the lower surface of the punch holder 7,
A second cutting blade 13 arranged at a predetermined interval on the upstream side of the first cutting blade 12, a first and a second cutting blade 12,
In order to operate 13 alternately, the punch holder 7 and the first
And the second cutting blades 12 and 13, respectively, are interposed between the cutting blades 12 and 13 during operation, and advance above the cutting blades 12 and 13 to prevent the rise, and retreat from above the cutting blades 12 and 13 during non-operation. First controlled to operate alternately to allow the rise
And the second movable spacers 16 and 17 are provided to configure a manufacturing apparatus for a semiconductor device lead frame.

[0006]

According to the method of the present invention, the conductive long base material 10 which intermittently moves in the longitudinal direction is punched by the press die 8. The press die 8 has two unit pattern dies, and two unit patterns 2, 2 are simultaneously formed on the base material 10 by punching once.
A pair of patterns 23 consisting of is punched out. Then, an even number (8) of unit patterns 2 are formed by a predetermined number of times (for example, 4 times) of feeding, but after a predetermined number of times (4th) of feeding, a pair of units located below the cutting blade 12 is formed. By cutting the center A of the pattern 23, the lead frame 1 having an odd number (7) of the unit patterns 2 is formed. In the portion of the base material 10 corresponding to the next lead frame 1, since one unit pattern 2 left by the previous cutting is already formed, the number of times subtracted once from the predetermined number (4 times) (3 times ), The end B of the pair of patterns 23 located below the cutting blade 13 is cut, and the same number (7 pieces) as the tip is cut.
The lead frame 1 having the unit pattern 2 is formed. That is, the lead frame 1 having an odd number of unit patterns 2 is formed by alternately changing the cutting position between the center A and the end B of the pair of patterns 23.

To change the cutting position, the first cutting blade 1
The second and second cutting blades 13 alternately cut the base material 10.
The cutting blades 12 and 13 together with the punch holder 7 form the base material 10
It descends in synchronization with the stop after the feeding operation of. However, in the state where the movable spacers 16 and 17 are not interposed between the cutting blades 12 and 13 and the punch holder 7, even if the cutting blades 12 and 13 hit the base material 10, they are relatively pushed up, so that the base material 10 is pushed up. I can't disconnect. On the other hand, if the movable spacers 16 and 17 move and the movable spacers 16 and 17 intervene between the cutting blades 12 and 13 and the punch holder 7, the cutting blades 12 and 13 cannot rise, so that the punch holder 7 cannot move. The base material 10 can be cut by lowering. Then, by controlling the reciprocating movement of the movable spacers 16 and 17, the cutting blades 12 and 13 are alternately and selectively operated to change the cutting position of the base material 10.

[0008]

An embodiment of the present invention will be described with reference to the drawings.
In FIGS. 1 and 2, reference numeral 1 is a lead frame, which includes seven unit patterns 2. The unit pattern 2 includes a semiconductor mounting portion 3, an inner lead 4, an outer lead 5,
It is formed by punching so as to have the connecting bar 6. Each unit pattern 2 corresponds to one semiconductor device.

As shown in FIG. 3, the conductive long plate-shaped base material 10 on which the lead frame 1 is formed is longitudinally moved between the upper and lower punch holders 7 and the die holder 9 by a feeding device (not shown). While being intermittently sent to, the lead pattern is punched out and cut into a predetermined length.

A press die 8 is provided on the upstream side of the punch holder 7.
Is provided, and the cutting device 11 is provided on the downstream side. The die 22 is mounted on the die holder 9 so as to face the press die 8 and cooperates with the press die 8 to punch and form a lead pattern on the long plate-shaped base material 10. The press die 8 has two unit pattern dies corresponding to the two unit patterns 2 of the lead frame 1. Then, a pair of patterns 23 composed of two unit patterns 2 and 2 adjacent in the longitudinal direction are formed on the long plate-shaped base material 10 by one punching.
Can be punched out. FIG. 2 is a schematic view showing a base material 10 and a lead frame 1 in which a large number of unit patterns 2 and 2 are punched out. In FIG. 2, a pair of patterns 23 composed of two unit patterns 2 and 2 which are punched at the same time are shown separately by the presence or absence of hatching. The base material 10 is intermittently fed with the width of the two unit patterns 2 of the press die 8 as one pitch.

As shown in FIGS. 3 to 5, the cutting device 1
1 includes two cutting blades 12 and 13. Cutting blade 1
2 are arranged on the downstream side of the press die 8 at intervals corresponding to the feed pitch of the base material 10. The distance between the cutting blade 12 and the cutting blade 13 is set equal to the half pitch distance of the movement of the base material 10, that is, the width of the unit pattern 2.
The cutting blades 12 and 13 are held by a holding member 14 provided on the lower surface of the punch holder 7 so as to be able to move up and down. The holding member 14 is located above the cutting blades 12 and 13 and has a space 1
5 is provided. In the space 15, movable spacers 16 and 1 for determining the operation and non-operation of the cutting blades 12 and 13.
7 is horizontally reciprocally inserted. The base ends of the movable spacers 16 and 17 are connected to the iron cores of the solenoids 18 and 19. And the movable spacers 16, 1
The solenoid 7 is adapted to move forward to the tip side against the biasing force of the springs 24 and 25 by the excitation of the solenoids 18 and 19. The excitation timing of the solenoids 18 and 19 is controlled by a controller (not shown) based on a preset number of feeds. A recess 20 is formed in the lower portion of the movable spacers 16 and 17 on the tip side. This recess 20
The projections 21 at the upper ends of the cutting blades 12 and 13 are fitted in the cutting blades 12 and 13. As it rises and fits into the convex portion 21, the cutting blades 12, 13
Cannot cut the base material 10. However, when the concave portions 20 of the movable spacers 16 and 17 do not correspond to the convex portions 21 of the cutting blades 12 and 13 (state of FIG. 5), the movable spacers 16 and 17 prevent the cutting blades 12 and 13 from rising. Accordingly, the cutting blades 12 and 13 descend together with the punch holder 7 to cut the base material 10.

In this embodiment, the base material 10 is intermittently sent by a pitch by a carrying device (not shown), and the pair of patterns 23 is sequentially punched by the press die 8. The part where the unit pattern 2 is punched out is then sent to a position below the cutting device 9. In the cutting device 9, the cutting blades 12 and 13 alternately operate to cut the base material 10 into a predetermined length.

For example, from a certain reference position of the base material 10, 4
Eight unit patterns 2 (four pairs of patterns 23) are formed on the base material 10 by feeding and punching once. Then, from the reference position to the cutting blade 12 on the upstream side,
After the second feed, the pair of patterns 2 located below it
By cutting the center A of 3 with the cutting blade 12, the lead frame 1 having 7 unit patterns is formed. Therefore, one unit pattern 2 of the pair of patterns 23 is left at the tip of the base material 10. Since one unit pattern 2 is already included in the portion corresponding to the lead frame 1 formed by the next cutting, the cutting blade 13 on the upstream side has three times less than the previous feeding number. After the feeding, the ends of the pair of patterns 23 located therebelow are cut by the cutting blade 13 to form the lead frame 1 also having seven unit patterns. That is, the cutting blade 1 that cuts according to the number of feeds
By alternately changing 2 and 13, the lead frame 1 having an odd number of unit patterns 2 is formed.

At this time, the cutting and non-cutting operations of the cutting blades 12 and 13 are controlled by moving the movable spacers 16 and 17. That is, the recesses 20 of the movable spacers 16 and 17 are
In the state corresponding to the convex portion 21 of the cutting blades 12 and 13,
Although the cutting blades 12 and 13 do not escape upward to cut the base material 10, the cutting blades 12 and 13 do not escape upward so that the base material 10 is cut in a state where the concave portion 20 does not correspond to the convex portion 21.

In this embodiment, the lead frame 1 having seven unit patterns 2 is applied. However, the present invention is not limited to this, and the manufacturing of a lead frame having an odd number of unit patterns is performed. It can be widely applied.

[0016]

As described above, according to the present invention, the lead frame 1 having an odd number of unit patterns 2 can be formed by using the press die 8 having two unit pattern dies. Production efficiency is better than when using a press die that has a unit pattern die, and 3, 5, 7,
..Small size, simpler structure and cheaper than press type with unit pattern type, and widely applicable to any odd numbered or even numbered lead frame without special press type It has the effect of being able to.

[Brief description of drawings]

FIG. 1 is a plan view of a lead frame manufactured by the method of the present invention.

FIG. 2 is a schematic explanatory view of a base material punched with a large number of unit patterns and a lead frame formed by cutting the base material.

FIG. 3 is a schematic explanatory diagram of the manufacturing process of the lead frame.

FIG. 4 is a bottom view of the cutting device.

FIG. 5 is a front view of the cutting device.

[Explanation of symbols]

 1 Lead Frame 2 Unit Pattern 3 Semiconductor Mounting Part 4 Inner Lead 5 Outer Lead 7 Punch Holder 8 Press Type 9 Die Holder 10 Long Base Material 11 Cutting Device 12 First Cutting Blade 13 Second Cutting Blade 16 Movable Spacer 17 Movable Spacer 23 pairs of patterns

Claims (2)

(57) [Claims] 1. A press die having two unit pattern dies aligned in the moving direction while intermittently moving a conductive long base material in the longitudinal direction, and forming a long base material from two adjacent unit patterns. Punching a pair of patterns that are arranged in the longitudinal direction one after another, positioned on the downstream side of the press die, and a cutting blade that operates in synchronization with the press die, to form a long base metal for each predetermined odd number of unit patterns. A method of forming a lead frame having an odd number of unit patterns by cutting, and cutting the center of a pair of patterns located below the cutting blade with the cutting blade after the long base material has moved a predetermined number of times. The step of forming one lead frame, and after this step, the end of the pair of patterns positioned below the cutting blade is moved after the long base material has been moved by one less than the predetermined number of times. To disconnect with Ri, method for producing a lead frame for semiconductor device and repeating the step of forming another lead frame, alternately. 2. A feed device for intermittently moving a conductive long base material in the longitudinal direction, and two unit pattern molds attached to the lower surface of a punch holder and arranged in the moving direction of the long base material. A press die that performs a punching operation after the movement of the long base material to sequentially punch a pair of patterns of two adjacent unit patterns on the long base material to form a plurality of unit patterns arranged in the longitudinal direction, A first cutting blade which is attached to the lower surface of the punch holder at a predetermined distance on the downstream side of the press die and cuts the center of a pair of patterns located below after the long base material has moved a predetermined number of times; After the first cutting blade is operated by being attached to the lower surface of the punch holder at a predetermined interval on the upstream side of the first cutting blade, the number of times the long base material is one time less than the predetermined number of times. After moving, the pair of A second cutting blade for cutting the end of the turn, and alternately operating the first and second cutting blades,
The cutting blade is interposed between the punch holder and the first and second cutting blades, respectively, and moves upward of the cutting blade during operation to prevent the cutting blade from rising, and when not operating, retreats from above the cutting blade to cut the cutting blade. And a first movable spacer which is controlled so as to alternately operate so as to allow the rise of the semiconductor device.