JPH08132443A - Mold positioning structure - Google Patents

Abstract

PURPOSE: To position upper and lower molds for producing an IC by a reduced number of fitting blocks and to ensure high abrasion resistance. CONSTITUTION: Two male blocks 15 formed into a conical shape are provided to an upper mold 13 so as to protrude toward a lower mold 11. Two female blocks 17 having conical cavity parts 17a having the same shape as the male blocks 15 and receiving the male blocks 15 when the upper and lower molds 11, 13 are joinned at a predetermined relative position are provided to the lower mold 11. The male and female blocks 15, 17 are formed from a hard alloy and diamond coating is pref. applied to the outer peripheral surfaces of both blocks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning structure for an upper die and a lower die in an IC manufacturing mold.

[0002]

2. Description of the Related Art Generally, a die for manufacturing an IC is divided into an upper die and a lower die. For this reason, a positioning structure that determines the relative positions of the upper mold and the lower mold is required when the two are matched during the manufacture of the IC. An example of this type of positioning structure provided with an uneven block for positioning the upper die and the lower die will be described with reference to FIGS.

FIG. 5 is a perspective view of an upper die and a lower die of the conventional structure, FIG. 6 is a perspective view of the upper die and the lower die showing a mounting state of the conventional block, and FIG. 7 is a perspective view of the conventional block. As shown in FIG. 5, a rectangular upper mold 7 is provided above the rectangular lower mold 5 on which the lead frame 1 and the tablet 3 are set so as to be clampable by a mold clamping mechanism (not shown). As shown in FIG. 6, four sets of blocks 9 are provided on the front, rear, left, and right edges of the lower mold 5 and the upper mold 7, which are fitted in a concavo-convex shape. The blocks 9 are concave blocks 9a on the lower mold 5 side.
The upper block 7 side is the convex block 9b. Conventionally, the concave blocks 9a and the convex blocks 9b are formed of SK material (carbon steel material), and the surfaces thereof are subjected to chrome plating treatment.

The convex block 9b provided on the upper mold 7 becomes a hexahedral convex portion and is projected from the lower surface of the upper mold 7. On the other hand, the concave block 9a becomes a concave portion into which the convex block 9b fits without rattling and is opened on the upper surface of the lower mold 5. The concave block 9a and the convex block 9b are arranged so as to coincide with each other only when the lower die 5 and the upper die 7 are in a predetermined relative position. That is, by fitting the concave block 9a and the convex block 9b, the lower mold 5 and the upper mold 7 are reliably positioned in the X direction, the Y direction, and the θ direction (rotational direction).

In the die having such a positioning structure, the upper die 7 is reliably positioned on the lower die 5 on which the lead frame 1 and the tablet 3 are set via the concave block 9a and the convex block 9b, and The IC plastic package was molded by holding the mold 5 and the upper mold 7 under pressure for a certain period of time.

[0006]

However, in the conventional positioning structure, four sets of blocks 9 have to be provided in the front, rear, left and right of the lower mold 5 and the upper mold 7, so that a total of eight block mounting processes are required. However, there is a problem that the man-hours for machining and mounting increase, and the man-hours for exchanging work increase when the block is worn. Further, since the conventional block 9 is formed of SK material with the surface being subjected to chrome plating, sufficient abrasion resistance cannot be obtained, and the wear rate is high, so replacement frequency is high and management costs are high. There was a problem to do. The present invention has been made in view of the above circumstances, and provides a mold positioning structure in which reliable positioning can be performed with a small number of blocks, and the frequency of block replacement is reduced due to high wear resistance, and the number of processing attachment steps is increased. It is intended to reduce the die manufacturing cost by reducing the number of steps and the wear management cost by reducing the number of replacement work steps.

[0007]

In order to achieve the above object, a mold positioning structure according to the present invention has a set of engageable blocks extending between an upper mold and a lower mold of an IC manufacturing mold. It is a mold positioning structure for relatively positioning the upper mold and the lower mold through this block, and two male blocks formed in a conical shape are projected in the lower mold direction to the upper mold. In addition to having a conical cavity with the same shape as this male block, the lower die was provided with two female blocks that fit into the male block without rattling when the upper die and the lower die are joined at a predetermined relative position. It is characterized by that.
Further, in the mold positioning structure, it is preferable that the male block and the female block are made of cemented carbide and the outer peripheral surface of the male block and the inner peripheral surface of the conical cavity of the female block are diamond-coated.

[0008]

The male block and the female block are formed in a conical fitting structure, and the entire outer peripheral surface of the male block is in contact with the female block while being surrounded by the conical cavity of the female block. With, one reference point can be easily determined. Therefore, by providing the two sets of the male block and the female block, the movement of the lower die and the upper die on the joining plane is restricted at the two reference points, and the relative positions are determined. Further, since the male block and the female block are formed by subjecting the cemented carbide to the diamond coating treatment and the abrasion resistance at the time of fitting is enhanced, the abrasion of the male block and the female block is reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of a mold positioning structure according to the present invention will be described in detail below with reference to the drawings. 1 is a perspective view of a mold having a positioning structure of the present invention, FIG. 2 is a perspective view of a block portion, and FIG. 3 is a sectional view of the block portion in a fitted state. Above the rectangular lower mold 11 on which the lead frame and the tablet are set, the rectangular upper mold 13 is also provided.
Is provided so that it can be clamped by a mold clamping mechanism (not shown). For example, conical protrusion-shaped male blocks 15 are fixed to the left and right edges of the upper mold 13, and the male blocks 15 are attached so that the apex side projects downward from the lower surface of the upper mold 13. The male blocks 15 may be provided on the front and rear edges or on both ends of the upper die 13 on the diagonal line.

On the other hand, the lower mold 11 corresponding to the male block 15
A female block 17 having a conical cavity portion 17a having the same shape as the male block 15 is provided on the left and right edges of the conical cavity portion 17a, and the conical cavity portion 17a of the female block 17 fits into the male block 15 without rattling. Male block 15 and female block 17
Are arranged so as to coincide with each other when the lower die 11 and the upper die 13 are in a predetermined relative position. That is, when the male block 15 and the female block 17 are fitted together, the lower mold 11 and the upper mold 13 are positioned at predetermined relative positions.

The male block 15 and the female block 17 are made of a high hardness cemented carbide made by sintering metal carbide powder and metal powder. Further, the surfaces of the male block 15 and the female block 17 are subjected to a diamond coating treatment so that abrasion resistance at the time of fitting can be improved.

In the mold positioning structure thus constructed, the entire outer peripheral surface of the male block 15 is contacted while being surrounded by the conical cavity portion 17a of the female block 17, which is different from the fitting structure of the hexahedral block. One set of male block 15 and female block 17 makes it easy to determine one reference point. Therefore, by providing the two sets of the male block 15 and the female block 17, two reference points on the joint plane of the lower die 11 and the upper die 13 are determined, and the lower die 11 and the upper die 1 are set.
3, the X direction, the Y direction, and the θ direction (rotational direction) are reliably positioned. Further, by performing diamond coating treatment on the cemented carbide, the male block 15 and the female block 17 are formed, and wear resistance at the time of fitting is improved, so that wear is reduced and block replacement frequency is reduced. .

According to the mold positioning structure described above, since the positioning block has the conical fitting structure, two sets of blocks can determine two reference points on the joining plane.
The number of blocks can be halved from the conventional one. Also,
Since the male block 15 and the female block 17 are formed by subjecting the cemented carbide to the diamond coating treatment, wear is reduced and the block replacement frequency can be reduced.

Further, in the above-mentioned mold positioning structure, the positioning block has the conical fitting structure, so that the following effects are produced. FIG. 4 is a sectional view of the positioning block after additional machining. That is, the male block 15 and the female block 17
When the male block 15 and the female block 17 are worn, or the fitting surface is not uniform, the male block 15 and the female block 17 are additionally processed on the outer circumferential surface of the male block 15 or the inner circumferential surface of the conical cavity portion 17a of the female block 17. By performing (cutting, polishing, surface coating, etc.), a uniform fitting surface can be re-formed and can be used repeatedly. In this case, the male block 15 and the female block 17 are additionally processed so that the apex angles are the same. In addition, the gap between the mating surfaces of the male block 15 and the female block 17 caused by the additional machining (for example, cutting work) is the bottom raising block 2 at the bottom of the hole where the male block 15 and the female block 17 are planted.
It can be removed by providing Nos. 1 and 23.

[0015]

As described above in detail, according to the mold positioning structure of the present invention, the conical male block is provided on the upper die, and the female block that fits the male block without rattling is attached to the lower die. Since two sets of male block and female block are provided on the lower mold and upper mold, movement on the joining plane is restricted at the two reference points, and reliable positioning can be performed with a small number of blocks. become. Also, if the male block and female block are made of cemented carbide and the outer peripheral surface of the male block and the inner peripheral surface of the conical cavity of the female block are diamond-coated, wear resistance during fitting is improved. Therefore, the block replacement frequency can be reduced. As a result, it is possible to reduce the die manufacturing cost by reducing the working and mounting man-hours and reduce the wear management cost by reducing the replacement work man-hours.

[Brief description of drawings]

FIG. 1 is a perspective view of a mold having a positioning structure of the present invention.

FIG. 2 is a perspective view of a block portion.

FIG. 3 is a sectional view of a block portion in a fitted state.

FIG. 4 is a cross-sectional view of a positioning block after additional machining.

FIG. 5 is a perspective view of an upper die and a lower die having a conventional structure.

FIG. 6 is a perspective view of an upper mold and a lower mold showing a mounting state of a conventional block.

FIG. 7 is a perspective view of a conventional block.

[Explanation of symbols]

11 Lower mold 13 Upper mold 15 Male block 17 Female block 17a Cone cavity 21 and 23 Bottom raising block

Claims (3)

[Claims] 1. A plurality of sets of engageable blocks are provided between an upper die and a lower die of an IC manufacturing mold, and the upper die and the lower die are relatively positioned through the blocks. A mold positioning structure for forming, wherein two male blocks formed in a conical shape are provided in the upper die by projecting in the direction of the lower die, and the male die has a conical cavity having the same shape as the male block. And a mold positioning structure, wherein the lower mold is provided with two female blocks that fit into the male block without rattling when the lower mold is joined at a predetermined relative position. 2. The male block and the female block are made of cemented carbide, and the outer peripheral surface of the male block and the inner peripheral surface of the conical cavity of the female block are diamond-coated. Item 1. The mold positioning structure according to item 1. 3. A bottom raising block is sandwiched between the respective bottom portions of the male block and the female block and the upper die and the lower die, and the male block and the female block are moved toward each other. The mold positioning structure according to claim 1, which is made possible.