JP2786135B2 - Cutting mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutting die for cutting a part of a plate-like member derived from a resin shell formed by sealing an IC chip with a resin.

[0002]

2. Description of the Related Art FIG. 4 is an exploded perspective view showing an example of a conventional cutting die, and FIG. 5 is a sectional view of the cutting die shown in FIG. Conventionally,
As shown in FIGS. 4 and 5, this type of cutting die has
A lead frame 17a having a resin outer shell 17 of C and a plurality of lead members extending from the periphery of the resin outer shell is sent and placed from one direction, and each of the lead 15a and the hole 15a into which the resin outer shell 17 is inserted is formed. A lower die including a holder 16 and a cutting die 15 having a corresponding slit-shaped cutting hole 14a derived from the periphery of the corresponding hole 15a;
And a top plate formed of a holder 11 and a punch plate 12 for holding a plurality of punches 13 inserted into the punch member and cutting the lead member.

[0003] Further, when the mold is clamped, the punch 13 is inserted into the cut hole 1.
A stripper 14 that guides the punch 14a and presses the lead member so that the punch 14a is precisely fitted to the 4a, and a guide post that guides the upper die and the lower die are provided.

[0004] With this cutting die, the lead frame 17
In order to separate the tie bar which is a part of the lead member of FIG. 1a and extract it as an IC from the lead frame 17a, first, the lead frame 17a is fed, the resin outer body 17 is inserted into the hole 15a of the lower cutting die 15, and the lead member is inserted. Are positioned in the cutting holes 14a for cutting the corresponding tie bars. Thereafter, the mold is clamped, the lead member is cut, and the cut IC, which is cut off from a tie bar, which is one of the lead members of the lead frame 17a, is stored in the storage box through the lower shooter from the hole 15a. You.

[0005] As described above, the resin outer body 17 mounted on the lead frame 17a is cut off by the cutting die so that I
The finishing process of C was completed.

[0006]

FIG. 6 is a sectional view of the cutting die of FIG. 4 for explaining the problem. However,
In the above-described conventional cutting die, as shown in FIG. 6, foreign matter 1 which is a resin residue adhered in a resin sealing step which is a previous step.
The punch 8 is sent with the foreign matter 18 attached to the lead member, and the punch 13 is lowered with the foreign matter 18 attached thereto, and the punch 13 is often broken or the cutting die is damaged.

In addition, even if the punch 13 is not damaged, the cutting edge of the punch 13 is deteriorated and the sharpness is deteriorated, or the lead member is fed with an uncut portion, causing jamming. In particular, this type of mold is automated, and because it is not possible to observe the inside, the cutting operation proceeds without an accident being discovered, and a large number of IC finishing defects occur, causing a great loss. Will be issued.

In order to remove such foreign matter 18, an air injection nozzle was provided at the entrance of the mold to attempt to blow off the foreign matter 18. However, the force for attaching the foreign matter 18 to the lead member can be blown off strongly. Did not.

Accordingly, an object of the present invention is to provide a cutting die capable of confirming the presence or absence of foreign matter.

[0010]

A feature of the present invention is that a plate-shaped lead frame having a resin outer body of an IC and a plurality of lead members extending from the periphery of the resin outer body is sent and placed in one direction. A lower die having a first hole into which the resin outer body is inserted, and a slit-shaped cutting hole corresponding to each of the lead members and derived from the periphery of the first hole; An upper die having a punch inserted into a hole and cutting the lead member, the cutting die having a surface extended in the one direction from the surface of the lower die and on which the lead member is placed, and A stage having a second hole into which the resin shell is inserted at a position before the frame is sent to the first hole, and the lead members and tips at four corners of the resin shell mounted on the stage; Contact Four bar-shaped members of which the other end from the upper surface of the serial upper mold is incorporated in the upper die so as to protrude, one of the other ends of four of said rod-like member protrude from the other
And a sensor for detecting that the cutting is performed.

The sensor includes a light emitting unit for projecting light to the other end of the rod-shaped member and receiving the light from the light emitting unit.
It is desirable to have a light receiving unit that emits light.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings.

FIG. 1 is an exploded perspective view of a cutting die showing one embodiment of the present invention. As shown in FIG. 1, this cutting die has a surface on which the lead member of the lead frame is placed, extending from the surface of the lower die 9, and having a hole 8a into which the resin shell is inserted. 1, a plurality of pins 4, the tips of which contact the lead member mounted on the detection stage 1 and whose other ends are slidably held by an upper holder 8, and the other end of any of these pins 4 Is provided with a sensor 2 for detecting that is protruded from the other. Other than that, the holder 10 and the stripper 7, and the cutting die 9 and the punch 6 are provided in the same manner as in the prior art.

The four pins 4 are provided so as to contact the four corners of the hole 8a. This is because most of the foreign matter adhering to the lead member is resin residue of the gate in the resin sealing mold. This is because the resin burrs do not adhere to the lead members located at positions other than the above, and even if they adhere, they can be easily removed only by blowing compressed air during transportation. Therefore, the foreign matter adhering to the lead member is at the position corresponding to the gate, that is, the lead member (called a suspension pin) at the four corners of the resin outer body. What is necessary is just to confirm whether or not there is a foreign substance in these four corners.

The mechanism for detecting the presence or absence of foreign matter on the lead members at the four corners is such that the pin 4 is attached to the holder 8 against the repulsive force of the spring 3.
The presence or absence of a foreign object is determined based on whether or not the protrusion is more prominent. That is, the light-emitting portion of the sensor 2 that projects light along the upper surface of the holder 8 and the light-receiving portion of the sensor 2 that receives the emitted light and converts it into current are arranged with their optical axes aligned, and four If any of the pins 4 protrudes from the holder 8, the light is blocked, so that the presence of foreign matter is determined. In the drawing, the light projecting portion and the light receiving portion of the sensor 2 are disposed facing each other, but a reflecting mirror for bending light so that all the pins 4 have the same optical axis is provided. . In other words, there is an advantage that a simple mechanism is sufficient.

FIG. 2 is a cross-sectional view showing a state where the cutting die of FIG. 1 is opened, and FIG. 3 is a cross-sectional view showing a state where the cutting die of FIG. 1 is closed. Next, the operation of the cutting die according to the embodiment of the present invention will be described with reference to FIGS. First, as shown in FIG. 2, the upper die holder 8 and the lower die holder 10 are opened, and a lead frame (not shown) is inserted between the stripper 7 and the detection stage 1.

Next, as shown in FIG. 3, when foreign matter 18 is present on the detection stage 1 when the mold is clamped, the pin 4 is positioned on the upper surface of the holder 8 so that the lead frame 17 a rides on the foreign matter 18. By protruding from the height, light on the optical axis 13 from the sensor 2 is blocked, and no light enters the light receiving portion. As a result, current does not flow, the holding relay of the interlock circuit is opened, and the sequence operation proceeds. At the same time, the alarm lamp lights up.

As described above, the presence or absence of the foreign matter 18 can be confirmed by the detection stage 1 immediately before the cutting, and the punch and the cutting die are not damaged in the subsequent cutting operation.

[0019]

As described above, according to the present invention, there is provided a rod member for contacting the tip of a lead member of a lead frame, which is sent before cutting, via a lead member.
By providing a sensor for detecting a state in which the multi-end protrudes upward when the rod member comes in contact with the foreign matter, the presence or absence of the foreign matter can be checked in advance. There is an effect that the lead member can be cut very stably without occurrence of defective products.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a cutting mold according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a state in which the cutting die of FIG. 1 is opened.

FIG. 3 is a cross-sectional view showing a state in which the cutting die of FIG. 1 is clamped.

FIG. 4 is an exploded perspective view showing an example of a conventional cutting die.

FIG. 5 is a sectional view of the cutting die of FIG. 4;

6 is a cross-sectional view of the cutting die of FIG. 4 for explaining a problem.

[Explanation of symbols]

 Reference Signs List 1 detection stage 2 sensor 3 spring 4 pin 5,12 punch plate 6,13 punch 7,14 stripper 8,10,11,16 holder 8a, 15a hole 9,15 cutting die 13 optical axis 14a cutting hole 17 resin outer body 17a Lead frame 18 Foreign matter

Continuation of the front page (56) References JP-A-62-106654 (JP, A) JP-A-4-192553 (JP, A) JP-A-4-284925 (JP, A) JP-A-4-132247 (JP) , A) Hikaru 4-74450 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 23/50 B21D 28/00

Claims (2)

(57) [Claims] A plate-like lead frame having a resin outer body of an IC and a plurality of lead members extending from a periphery of the resin outer body is sent and placed from one direction, and the resin outer body is inserted. A lower die having one hole and forming a slit-shaped cutting hole corresponding to each of the lead members and derived from the periphery of the first hole; and cutting the lead member inserted into the cutting hole. In a cutting die having an upper die having a punch, the cutting die has a surface extended in the one direction from the surface of the lower die and on which the lead member is placed, and the lead frame is sent to the first hole. A stage having a second hole into which the resin outer body is inserted at a previous stage, and contacting the leading ends of the lead members at the four corners of the resin outer body mounted on the stage with other ends from the upper surface of the upper die. The ends can protrude Four rod-shaped members to be incorporated into the upper die as described above, and the other of any of the four rod-shaped members
A sensor for detecting that the end is protruding from the other . 2. The sensor according to claim 1, wherein the sensor is configured to project light onto the other end of the rod-shaped member, and receive the light from the light-emitting unit .
Claim 1 cutting die, wherein further comprising a light receiving unit that.