JPH0982867A - Lead terminal forming device of electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an upper forming die to be mounted independent of mounting directivity so as to carry out a die mounting operation easily when the lead terminals of an electronic part of a lead frame are bent by a method wherein relief holes provided to the upper forming die are formed into ellipses whose major axes extend along the lengthwise direction of the lead frame. SOLUTION: A lower die 3 is equipped with forming dies 5 and 6 on its upper surface and pilot pins 7 to 10 fitted in pilot holes provided to the lateral side bands of a lead frame 1. An upper die 11 is equipped with forming punches 13 and 14 and relief holes 15 to 18 corresponding to the pilot pins 7 to 10. Especially, the relief holes 15 to 18 provided to the upper die 11 are formed into ellipses whose major axes extend along the lengthwise direction of the lead frame 1. Therefore, the upper die 11 can be mounted independent of its sense on an up-down head which moves the upper die 11 in a vertical direction, so that the upper die 11 can be mounted independent of mounting directivity and markedly lessened in mounting man-hours, and a forming device of this constitution is improved in workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, in the process of manufacturing an electronic component such as a transistor or an IC using a lead frame, directs each lead terminal projecting from a mold portion for packaging an element portion of the electronic component downward. The present invention relates to a forming device for bending into a rectangular shape.

[0002]

2. Description of the Related Art Generally, when manufacturing an electronic component such as a transistor or an IC using a lead frame, after the element portion of each electronic component is packaged by a synthetic resin mold portion, Forming processing of bending each lead terminal protruding from the mold portion downward is performed.

In this forming process, a lead frame provided with electronic components is formed on the lower die for forming, and pilot holes are formed in the left and right side bands of the lead frame from the lower die. Positioning is performed by fitting the pilot pin protruding upward, and in this state, the upper die is moved downward toward the lower die, whereby each lead terminal in the electronic component of the lead frame is moved to the lower die. The forming die and the forming punch in the upper die are bent downward.

In this case, the upper die is formed with an escape hole into which the tip of each pilot pin of the lower die fits.

[0005]

By the way, in the lead frame for manufacturing an electronic component, a pilot hole formed in each of the left and right side bands is used to identify the direction of the lead frame. In addition, it is said that the pilot hole in one of the left and right side bands of the lead frame and the pilot hole in the other side band are to be formed in a portion that is shifted by an appropriate dimension along the longitudinal direction of the lead frame. It is configured.

Therefore, among the pilot pins of the lower die, one pilot pin fitted in the pilot hole of one side band of the lead frame and the other pilot pin fitted in the pilot hole of the other side band of the lead frame. In accordance with the pilot holes in the lead frame are displaced along the longitudinal direction, it must be provided in a portion displaced by an appropriate dimension along the longitudinal direction of the lead frame,
Accordingly, also in the upper die, a clearance hole for the pilot pin into which the pilot hole of one side band in the lead frame fits and a clearance hole for the pilot pin in which the pilot hole of the other side band in the lead frame fits And must be formed in a portion displaced by an appropriate dimension along the longitudinal direction of the lead frame.

That is, since the escape holes formed in the upper mold are offset along the longitudinal direction of the lead frame, they are asymmetrical with respect to the longitudinal center line of the lead frame, and thus the escape holes are formed. When mounting the upper die having the holes to the vertically moving head for moving the upper die up and down, the relief holes provided in the upper die should be different from the pilot pins in the lower die. It is necessary to check whether or not it is compatible with each time each time it is mounted, and to mount it in the correct direction, which requires a great deal of labor and time, and the workability of mounting is low. There was a problem that the mold could be damaged by mounting in the wrong direction.

In order to solve the above problem, it is conceivable that the mounting portion of the upper mold for the vertical moving head can be mounted only when the upper mold is oriented correctly. There are various sizes of upper molds attached to the vertical moving head according to the size of electronic parts, and thus this method is configured to be compatible with all upper molds of different sizes. You cannot do it.

An object of the present invention is to provide a forming apparatus which does not cause such a problem.

[0010]

In order to achieve this technical object, the present invention provides: "A lower die having a forming die and pilot pins fitted in pilot holes in both left and right side bands of a lead frame; In a forming device including a forming punch on the lower surface and an upper die having escape holes for the pilot pins,
Each escape hole in the upper die is formed as an oval hole having an inner diameter increased along the longitudinal direction of the lead frame. ".

[0011]

[Operation] In this way, each escape hole in the upper mold,
By forming an oval hole whose inner diameter is increased along the longitudinal direction of the lead frame, one pilot pin that fits into the pilot hole of one side band of the lead frame among the pilot pins of the lower mold and the lead Even if the other pilot pin that fits in the pilot hole of the other sideband in the frame is displaced in the longitudinal direction of the lead frame, both of this one pilot pin and the other pilot pin are configured to fit in the same clearance hole. Therefore, the upper mold may be mounted in either the left or right direction with respect to the vertical movement head for vertically moving the upper mold, and the directionality of mounting in the upper mold is lost. It is possible.

[0012]

As described above, according to the present invention, the number of steps required for mounting the upper mold can be greatly reduced, workability can be improved, and the mold can be prevented from being damaged due to an incorrect mounting direction. It has a preventable effect.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.
The drawing of FIG. 6 will be described. In this figure, reference numeral 1
Indicates a lead frame. In the lead frame 1, an electronic component 2 including a mold portion 2a for packaging the element portion and a plurality of lead terminals 2b protruding from both left and right sides of the mold portion 2a is provided. The lead frames 1 are provided at intervals of an appropriate pitch P, and one side band 1a of the left and right side bands 1a and 1b of the lead frame 1 has an intermediate portion between the electronic components 2.
That is, the pilot hole 1a ′ is located at the position L1 = P / 2 from the center of each electronic component 2, and the other side band 1b is
Pilot hole 1 at the position L2 from the center of each electronic component 2
b ′ are provided respectively, and the pilot holes 1 a ′ on one side band 1 a and the pilot holes 1 b ′ on the other side band 1 b are arranged in the longitudinal direction of the lead frame 1 by an E dimension (E = L 1 − L2) is offset.
Furthermore, the lead frame 1 is intermittently transferred at intervals (2P) between the two electronic components 2 along the longitudinal direction.

Reference numeral 3 indicates a lower die arranged on the lower surface side of the lead frame 1, and the lower die 3 is attached to a fixed base 4 by a bolt (not shown). Two forming dies 5 and 6 are provided on the upper surface of the die 3 at intervals (3P) between the three electronic components 2, and further, on the upper and lower sides of the lower die 3, both forming dies 5 and 6 are formed on both sides. Pilot pins 7, 8, 9 and 10 are provided in the portion of the above so as to project upward, and one of the pilot pins 7, 8, 9 and 10 at one end of both forming dies 5 and 6 is provided. The pins 7 and 9 are located at a distance L1 from the center of the electronic component 2 along the longitudinal direction of the lead frame 1, and the other pilot pins 8 and 10 at the other ends of the forming dies 5 and 6 are From the center of part 2 By each provided at a portion at a distance L2 along the longitudinal direction of the lead frame 1, one of the pilot pins 7 and 9, one of the sideband 1a pilot hole 1a in the lead frame 1 '
In addition, the other pilot pins 8 and 10 are configured to fit into the pilot holes 1b 'in the other side band 1b of the lead frame 1.

Reference numeral 11 denotes an upper die arranged on the upper surface side of the lead frame 1, and the upper die 11 is of a vertically moving head 12 which moves down toward the base 4 and then moves up. The lower surface of the upper die 11 is attached to the lower surface of the upper die 11 by bolts (not shown), and the forming punch 1 for each of the forming dies 5 and 6 of the lower die 3 is formed.
3, 14 are provided, and when the upper die 11 is moved down, the pilot pins 7, 8 in the lower die 3 are provided.
Escape holes 15, 16 and 17, which allow 9 and 10 to be fitted,
18 is provided.

Then, the escape holes 15, 16, 17,
The reference numeral 18 indicates a displacement dimension E between the pilot holes 1a ′ of one side band 1a of the lead frame 1 and the pilot holes 1b ′ of the other side band 1b of the lead frame 1 along the longitudinal direction of the lead frame 1. Only the larger oval hole is formed. In this configuration, when the intermittent transfer of the lead frame 1 is stopped, the lead frame 1 is moved down to move the lead frame 1 downward.
Since the pilot pins 7, 8, 9, 10 of the lower die 3 are fitted in the pilot holes 1a ', 1b' of the lead die 1, the lead frame 1 is positioned with respect to the lower die 3. .

Then, by lowering the upper die 11, the lead terminals 2b of the two electronic components 2 are connected to the forming dies 5 and 6 of the lower die 3 and the upper die 1.
6 with both forming punches 13 and 14 in FIG.
As shown in, it is bent downward. When the bending process is completed, the upper die 11 is moved upward, and then the lead frame 1 is moved upward and then transferred by 2P. Thereafter, by repeating the above operation, the lead of each electronic component 2 in the lead frame 1 is moved. The terminal 2b is bent downward.

Then, as shown in FIG. 6, when the upper die 11 is moved downward with respect to the lower die 3, the tips of the pilot pins 7, 8, 9, 10 in the lower die 3 are , The relief holes 15, 16, 17 formed in the upper mold 11,
It will fit in 18. In this case, the upper die 1
When the escape holes 15, 16, 17, 18 in 1 are not formed as oval holes, when the upper mold 11 is attached to the lower surface of the vertically moving head 12, the direction of the upper mold 11 is changed. , The respective escape holes 15, 16, 17, 18
Therefore, it is necessary to check whether or not each of the pilot pins 7, 8, 9, 10 at the location corresponding to each of the escape holes 15, 16, 17, 18 is in a state of fitting. This requires a great deal of labor and time, and the workability of mounting is low, and the mold may be damaged by mounting in the wrong direction.

On the other hand, as described above, the upper die 1
The escape holes 15, 16, 17 and 18 of the lead frame 1 are arranged along the longitudinal direction of the lead frame 1 so that the pilot holes 1a 'of one side band 1a of the lead frame 1 and the pilot holes 1a' of the other side band 1b of the lead frame 1 respectively. When the hole is formed in an elliptical hole having a larger displacement E from the pilot hole 1b ', one pilot pin 7, 9 located at one end of both forming dies 5, 6 in the lower die 3 and The other pilot pins 8 and 10 located at the other ends of both forming dies 5 and 6 are provided with one escape hole 15 and 17 located at one end of both forming punches 13 and 14 in the upper die 11 and both The other escape holes 16 and 1 located at the other ends of the forming punches 13 and 14, respectively.
The upper die 11 may be attached to the vertically moving head 12 in any of the left and right directions, in other words, the upper die 11 can be fitted in any of the eight escape holes 15, One of the pilot pins 7 and 9 is attached to 17 so that the other pilot pin 8 and 10 fits into the other escape holes 16 and 18, respectively, or the other pilot pin is attached to one of the escape holes 15 and 17. The pins 8 and 10 may be attached so that the pilot pins 7 and 9 on one side fit into the escape holes 16 and 18 on the other side, respectively.
It is possible to eliminate the mounting directionality at 0.

[Brief description of drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention.

FIG. 2 is a plan view taken along the line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a plan view as viewed from IV-IV in FIG. 1;

5 is a bottom view taken along line VV of FIG. 1. FIG.

FIG. 6 is a diagram showing a state of forming.

[Explanation of symbols]

 1 lead frame 1a, 1b side band 1a ', 1b' pilot hole 2 electronic component 2a mold part 2b lead terminal 3 lower mold 4 base plate 5,6 forming die 7,8,9,10 pilot pin 11 upper mold 12 Vertical movement head 13,14 Forming punch 15,16,17,18 Escape hole

Claims (1)

[Claims] 1. A lower die having a forming die and pilot pins fitted in pilot holes in both left and right side bands of the lead frame, and an upper die having a forming punch and escape holes for the pilot pins on the lower surface. In a forming device including a die, each escape hole in the upper die is formed into an oval hole having an inner diameter enlarged along the longitudinal direction of the lead frame. .