JP3337557B2 - Unnecessary part punching device for lead frame for electronic parts - 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 frame used in the manufacture of electronic parts, and a tie bar provided between lead terminals of the lead frame or an unnecessary portion such as a peripheral portion of the lead terminal. The present invention relates to a device for punching out.

[0002]

2. Description of the Related Art Generally, a lead frame A used in the production of electronic components has a structure as shown in FIGS.
When a tie bar A2 is integrally provided between the lead terminals A1 constituting one electronic component to form a synthetic resin mold portion A4 that packages a portion of the semiconductor element A3 in each electronic component, While the tie bar A2 is configured to block the molten synthetic resin, the tie bar A2 is formed into the receiving die B1 on the lower surface side of the lead frame A after the molding portion A4 is formed.
Then, punching is performed by a punch B2 that moves back and forth with respect to the receiving die B1.

A conventional tie bar A2 punching device mounts a receiving die B1 on the upper surface of a fixed base 1 while moving the movable head 2 up and down toward the fixed base 1.
(However, the movable head 2 is guided so as to move up and down without lateral displacement along a guide shaft erected from the upper surface of the fixed base 1, although not shown). A punch B2 is attached to a die B1, and a pressing head 3 for a lead frame A is suspended from a lower surface of the movable head 2 by a guide pin 4 so as to be vertically movable. Is urged downward by a spring 5 provided to the guide pin 4, and further, the punch B 2 is slidably inserted into a through hole 6 formed in the holding head 3, 7, the lead frame A is pressed by the holding head 3 against the receiving die B1, as shown in FIG.
2 is configured to be punched by the punch B2 and the receiving die B1.

When the tie bar A2 is punched, each tie bar A2
Must be accurately aligned with the receiving die B1 and the punch B2. Therefore, in the conventional punching device, positioning holes A formed on the left and right sides of the lead frame A are formed on the lower surface of the holding head 3.
5 are implanted, and each of the pilot pins 7 is firstly moved with the downward movement of the movable head 2.
By entering the positioning holes A5 in the lead frame A, each tie bar A2 in the lead frame A
The receiving die B1 and the punch B2 are aligned.

[0005]

However, in the lead frame A, each positioning hole A5 and each tie bar A
In spite of the fact that there is some variation in the size between 2 and the conventional punching device,
As described above, the punch B2 is slidably inserted into the through hole 6 formed in the holding head 3, while the pilot pin 7 fitted into the positioning hole A5 in the lead frame A is implanted in the holding head 3. In other words, since the relative position between each pilot pin 7 and the punch B2 is fixed, when each tie bar A2 in the lead frame A is punched, each positioning hole A5 in the lead frame A is punched. And the tie bars A2, the size of the positioning holes A5 in the lead frame A and the size of the tie bars A2, and the size of the pilot pin 7 and the punch B2 in the punching device. Due to the dimensional error, punching residue may occur in a part of each tie bar A2,
There is a problem that a part of the lead terminal A1 is often cut off.

An object of the present invention is to provide a punching device that solves this problem.

[0007]

In order to achieve this technical object, the present invention provides a receiving die mounted on an upper surface of a fixed base and a punch mounted on a lower surface of a movable head which moves up and down toward the fixed base. And a pressing head suspended vertically on the lower surface side of the movable head, wherein the punch is slidably inserted into a through hole formed in the pressing head, and further, the pressing head is In a punching device comprising a pilot pin fitted downwardly in a positioning hole of a lead frame, a pilot member is attached to the holding head so as to be movable in a lateral direction, and the pilot pin is implanted in the pilot member. Will be installed. "

[0008]

[Function] As described above, the pilot pin fitted into the positioning hole in the lead frame is implanted in the pilot member which is mounted on the holding head so as to be adjustable in the lateral direction. Since the relative positional relationship can be arbitrarily adjusted by moving the pilot member in the lateral direction with respect to the holding head, unnecessary portions such as tie bars in the lead frame can be punched out of unnecessary portions such as tie bars. Accurate positioning can be achieved with respect to the punch and the receiving die.

[0009]

Therefore, according to the present invention, when punching an unnecessary portion such as a tie bar in a lead frame,
Due to dimensional variations and dimensional errors, there is an effect that it is possible to surely reduce the occurrence of uncut portions in unnecessary portions such as the tie bars and cutouts of required portions such as lead terminals.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In this figure, reference numeral 11 denotes a fixed base provided below the lead frame A, and reference numeral 12 denotes
Each of the movable heads is provided above the lead frame A so as to move up and down toward the fixed base 11. The movable head 11 is guided so as to move up and down along a guide shaft (not shown) erected from the upper surface of the fixed base 1 without lateral displacement.

A receiving die B1 for punching each tie bar A2 of the lead frame A is mounted on the upper surface of the fixed base 11, while a punch B1 for the receiving die B1 is provided on the lower surface of the movable head 12. Installed. Reference numeral 13 denotes a pressing head disposed on the lower surface side of the movable head 12, and the pressing head 13
Is composed of a lower press head 13a and an upper press head 13b, which are fastened to each other by a plurality of fixing bolts 18, and is suspended from the movable head 12 by a guide pin 14 so as to be vertically movable. Further, the pressing head 13 is urged downward by a spring 15 provided for the guide pin 14.

Further, a through hole 16 is formed in the holding head 13, and the punch B 2 is formed in the through hole 16.
Are slidably fitted. Lower surface pressing head 13a and upper surface pressing head 13b of the pressing head 13
A pilot member 19 formed in the shape of a plate is interposed movably in the lateral direction between the pilot member 19 and the pilot member 19 by adjusting screws 20 and 21 provided at both left and right ends of the lower surface holding head 13a. In FIG. 3, it is configured to move and adjust in the left-right direction, and the lower holding head 13a is provided with adjusting screws 22 and 23 provided at both front and rear ends in a direction perpendicular to the plane of FIG. It is configured to adjust the movement also in the front-back direction.

The pilot member 17 is fitted with a pilot pin 17 fitted in the positioning hole A5 of the lead frame A.
Is a large-diameter hole 13 formed in the lower surface holding head 13a.
It is planted so as to protrude downward from a '. In this configuration, when the movable head 12 is moved down, the pilot pin 17 first fits into the positioning hole A5 in the lead frame A with the descending movement, so that each tie bar A2 receives the lead frame A. After positioning the lead frame A against the receiving die B2 with the pressing head 13, the parts of the tie bars A2 in the lead frame A are combined with the punch B2. Punching is performed by the receiving die B1 (see FIG. 5).

At the time of this punching, the positional relationship between the pilot pin 17 and the punch B2 is determined by each tie bar A2 in the lead frame A by the receiving die B1 and the punch B.
It is necessary to set it so that it is positioned exactly with respect to 2. On the other hand, according to the present invention, as described above, the lower surface pressing head 13a of the pressing head 13
Fixing bolt 1 for fastening the upper surface holding head 13b and the upper surface holding head 13b
8 is adjusted and the pilot member 19 inserted therebetween is adjusted in the left and right direction by adjusting screws 20 and 21 provided on both left and right ends, or the adjusting screws 22 and 23 provided on both front and rear ends. The position of the pilot pin 17 implanted in the pilot member 19 and the punch B2 can be changed by adjusting the movement in the front-rear direction or in both the left-right direction and the front-rear direction. Each tie bar A2 in A receives a receiving die B1 and a punch B
2 so that the bolt 1
8 are fastened and fixed at that position, so that each positioning hole A5 in the lead frame A and each tie bar A
2, the respective tie bars A2 in the lead frame A can be accurately matched with the receiving die B1 and the punch B2.

In the above-described embodiment, the tie bar A2 between the lead terminals A1 in the lead frame A is punched. However, the case where the periphery for forming the lead terminals A1 in the lead frame A is punched out. Alternatively, when each lead terminal A1 is separated from the lead frame A, a part of the lead terminal A1 is punched out, or another punching is performed to cut out unnecessary lead terminals A1. Needless to say, it can be applied to.

As means for fixing the pilot member 19 at an arbitrary adjustment position, the lower-side pressing head 13a and the upper-side pressing head 1
3b is not limited to being fastened by the fixing bolt 18,
Pressing the pilot member 19 with bolts or the like
Alternatively, other fixing means such as fixing to 3 may be used.

[Brief description of the drawings]

FIG. 1 is a perspective view of a lead frame.

FIG. 2 is an enlarged sectional view taken along line II-II of FIG.

FIG. 3 is a vertical sectional front view showing the embodiment of the present invention.

FIG. 4 is a sectional view taken along line IV-IV of FIG. 3;

FIG. 5 is a vertical sectional front view showing an operation state in the embodiment of the present invention.

FIG. 6 is a vertical sectional front view of a conventional punching device.

FIG. 7 is a vertical sectional front view showing an operation state of a conventional punching device.

[Explanation of symbols]

 Reference Signs List A Lead frame A1 Lead terminal A2 Tie bar A3 Semiconductor element A4 Mold part A5 Positioning hole B1 Receiving die B2 Punch 11 Fixed base 12 Movable head 13 Pressing head 14 Guide pin 15 Spring 16 Through hole 17 Pilot pin 18 Fixing bolt 19 Pilot member 20 , 21,22,23 Adjusting screw

Claims (1)

(57) [Claims] 1. A receiving die mounted on an upper surface of a fixed base, a punch mounted on a lower surface of a movable head that moves up and down toward the fixed base, and a retainer suspended vertically on a lower surface side of the movable head. A head, wherein the punch is slidably inserted into a through hole formed in the holding head, and a pilot pin that fits into a positioning hole in the lead frame is provided on the holding head in a downward direction. In the punching device, a pilot member is attached to the holding head so as to be movable in a lateral direction, and the pilot pin is implanted in the pilot member. apparatus.