JPH0732407A - Molding die - Google Patents

Abstract

PURPOSE:To mold various types of articles with a resin by commonly using a center block, effectively kneading a melt resin for conducting resin molding with a good balance, and selecting a resin amount in accordance with the articles in conducting resin molding. CONSTITUTION:In a molding die in which a center block can be commonly used for various types of articles by connecting resin paths to each other with a through runner in the resin paths connecting pots A, B, C, D provided in the center block to cavities 20 of a cavity block, a lower through runner 16b and an upper through runner 18b are provided as the through runner on parting surfaces of a lower cavity block and an upper cavity block. The both are partially overlapped so that the resin paths are bent between the upper and lower molds. The lower through runner 16b is so disposed as to be extended in the longitudinal direction of the upper through runner 18b at the overlapped part thereof on the upper through runner 18b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding die used for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art When a product type is changed in a multi-pot type transfer molding apparatus, the molding die must be replaced for each product. In that case, a center block having a pot and a cavity having a cavity are usually formed. Swap both blocks. This is because the amount of resin is different depending on the product and the pot size is different,
This is because the number of pots varies, and in the cavity block, the cavity size differs for each product.

The applicant of the present invention has a structure of a molding die which commonly uses a center block for molding different products for the purpose of facilitating the work of changing the kind and reducing the die manufacturing cost. Proposed (JP-A-4-197720). 6 and 7 show the structure of the above molding die. Since this molding die shares the center block 5, the mold runner for connecting the cavity 7 and the pot 8 provided in the molding die 6 is provided with the through runner 9 for interconnecting the cavities 7. And

The molten resin flows into the through runners 9 from the respective pots 8 and serves as a common resin path to fill the respective cavities 7 with the resin. 6 and 7 show the lower mold, the pot and the through runner 9 are in communication with each other via a mold cull provided in the upper mold. In this way, if the through runners 9 are provided and the cavities 7 are communicated with each other, the cavities 7 and the through runners 9 provided in the molding die 6 are properly designed as shown in the figure even when resin-molding different products. This makes it possible to use the center block 5 in common.

[0005]

By the way, in the case of actually resin-molding different kinds of products, the size of the cavity and the like differ depending on the products, and the amount of resin used also differs. Therefore, when resin-molding different products, it is necessary to appropriately adjust the amount of resin used. In such a case, conventionally, even if resin tablets of different sizes are used, or even if the same resin tablet is used for different products, it is necessary to appropriately adjust the mold runner design etc. to complement the difference in cavity volume. I have to.

In the present application, the center block is commonly used when resin-molding different kinds of products as described above, and even if the amount of resin used is different due to the difference in the size of the cavity, etc. Accordingly, it is an object of the present invention to provide a molding die in which the amount of supplied resin can be easily changed to perform resin molding.

[0007]

The present invention has the following constitution in order to achieve the above object. That is, the resin blocks that connect the pots provided in the center block and the cavities of the cavity block are connected to each other by through runners in the middle of the resin channels, and the center block can be commonly used for different products. In the molding die, the through runners are provided on the die matching surfaces of the lower die cavity block and the upper die cavity block as a lower through runner and an upper through runner, with the resin paths partially overlapping so as to bend between the upper and lower dies. It is characterized by Further, the upper through runner is provided so as to communicate with all the cavities provided in the lower mold cavity block, and only the pot through which the resin tablet is put among the pots provided in the center block for the lower through runner and the upper through runner are provided. It is characterized in that the lower through-runner is provided so as to extend in the longitudinal direction of the upper through-runner at the overlapping portion with the upper through-runner.

[0008]

[Function] The lower and upper cavity blocks that clamp the molded product are provided with a lower through runner and an upper through runner, respectively, and the molten resin pumped from the pot of the center block passes through the lower through runner and the upper through runner. And the cavity is filled. When the resin tablet is selectively supplied to the pot of the center block, the resin tablet is supplied only to the pot having the lower through runner which is in contact with the upper through runner to perform resin molding. As a result, a resin mold in which the amount of supplied resin is appropriately adjusted by using the common center block is possible. The lower through runner and the upper through runner communicate with each other only between the pot to which the resin tablet is supplied and the cavity, and the required resin molding can be performed regardless of the other pots.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a sectional view of an embodiment of a molding die according to the present invention. In the figure, 10 is a pot, 1
2 is a lower mold center block, 14 is an upper mold center block, 16 is a lower mold cavity block, and 18 is an upper mold cavity block. The lower mold cavity block 16 and the upper mold cavity block 18 are provided with cavity recesses 16a and 18a, respectively. 20 is a cavity.

In the molding die of the embodiment, the center block is used in common so that it is fixedly installed and the cavity block is replaceable. FIG. 2 shows the configuration of the center block and the cavity block and how the cavity block is set. In the figure, the A side is the lower mold and the B side is the upper mold. On the lower mold side, the lower mold center block 12 provided with the pot 10 is fixed to the lower mold base block 13, and a storage space for housing the lower mold cavity block 16 is provided on the side of the lower mold center block 12, and the storage space is provided. The lower mold cavity block 16 is configured to be slid into the space. A lower die ejector pin plate 22 is set in the lower die cavity block 16.

On the upper die side, the upper die center block 14 provided with the die culls 14a is fixed to the upper die base block,
Like the lower mold, the upper mold cavity block 18 is slid from the side of the upper mold center block 14 and set. Reference numeral 24 is an upper ejector pin plate. The lower mold cavity block 16 and the upper mold cavity block 18 have the above-described cavity recesses 16 in them.
a and 18a are formed, but the cavity recess 16
A through runner for communicating between the cavities 20 is provided in the middle of the resin path connecting the pots 10a and 18a with each other.

In the embodiment, 16b is a lower through runner provided in the lower mold cavity block 16, and 18b is an upper through runner provided in the upper mold cavity block 18. Both the lower through-runner 16b and the upper through-runner 18b are provided on the mold matching surface of the cavity block slightly apart from the ends of the cavity recesses 16a, 18a and provided in the form of narrow grooves parallel to the direction in which the cavity recesses 16a, 18a are arranged. FIG. 3 is a sectional view showing the positional relationship between the lower through runner 16b and the upper through runner 18b.

As shown in the figure, the lower through-runner 16b and the upper through-runner 18b are set so as to partially overlap each other at the edge portions, and the lower through-runner 16b and the upper through-runner 18b are set.
The channels are connected by. Reference numeral 16c is a gate provided in the lower mold cavity block 16, and the gate 16c
Is communicated with the upper through runner 18b, and finally the resin path between the cavity 20 and the pot 10 is connected. As a result, the resin that is pressure-fed from the pot 10 will not be transferred to the mold cavity
a, lower through runner 16b, upper through runner 18b
And the cavity 20 is filled through the gate 16c. Reference numeral 30 is a lead frame of the molded product.

Since the lower through runner 16b and the upper through runner 18b communicate between the respective cavities, the center block 10 is used in common even when different kinds of products are resin-molded as in the conventional example shown in FIGS. Resin molding can be performed by replacing and setting only the cavity block. Particularly, in the case of the embodiment, the resin passage is provided by the lower through-runner 16b and the upper through-runner 18b so as to be bent, so that the resin kneading property is improved, and the resin passage is squeezed, so that The resin can be molded by making the injection balance of the resin uniform.

In resin molding, since the thickness and size of the resin mold portion differ depending on the product to be molded, the leads to be resin molded are subject to variations in the amount of resin required when the center block 10 is used in common. Frame products may be limited. 4 and 5 show that when the required resin amounts are different,
An example will be shown in which the resin amount is appropriately adjusted and used.

4 and 5, when the center block 10 is commonly used for resin molding, resin tablets are put into all pots and resin-molded as in the conventional example shown in FIGS. Instead, the number of resin tablets to be put into the pot is changed according to the product to cope with the difference in the required resin amount. FIG. 4 shows a case where a 4-pot center block is used, and FIG. 5 shows a case where a 5-pot center block is used, and shows an example in which a resin tablet is supplied to only two pots and resin molding is performed.

In the example shown in FIG. 4, a center block having four pots A, B, C and D is supplied with a resin tablet 32 to the two middle pots B and C for resin molding. In this case, the upper through runners 18b are communicated with all the cavities 20 in order to connect the pots B and C to the respective cavities 20, and the lower through runners 16b have only the resin paths from the pots B and C as the upper through runners 18b. Overlap to communicate. It should be noted that the resin tablets are not supplied to the pots A and D, and they are isolated from other pots and resin passages so as not to communicate with each other.

The example shown in FIG. 5 is a center block having five pots A, B, C, D and E, in which the resin tablets 32 are supplied only to the pots B and D for resin molding. In order to connect the pots B and D with the cavity 20, the pots B and D should be contacted and the lower through runner 16
b through and bottom through runners 1 for pots B and D
6b and the upper through runner 18b are provided so as to communicate with each other. Therefore, the lower through-runner 16b of the pot B is provided so as to overlap the upper through-runner 18b in the range where the resin paths do not communicate with the adjacent pots A and C.
Similarly, a lower through runner 16b communicating with the pot D is provided. In this way, only the pots B and D communicate with the cavity 20, and the pots A, C and E are isolated from the resin path.

Since the cavity block is provided with required cavity recesses and through runners according to the product, the lower through runner 16b and the upper through runner 18b can be designed appropriately according to the product. That is, by appropriately setting the lower through runners 16b and the upper through runners 18b according to the number and positions of the resin tablets supplied to the center block, the resin passages are communicated only between the pots supplying the resin tablets and the cavities. And the other pots can be isolated.

Since the thickness and size of the resin mold portion, the number of resin mold portions, etc. are different depending on the product, the amount of resin required for the product is selected, and the amount of resin supplied by the resin tablet, the volume of the cavity, By designing the molding die from the internal volume of the resin path and the like, resin molding with different resin amounts becomes possible. The following shows how much the resin amount can be changed by changing the number of resin tablets supplied to the pot in the case of 4 pots and the case of 5 pots.

[0021]

[Table 1]

[0022]

[Table 2]

Table 1 shows the case of pots, Table 2 shows the case of 5 pots, and the marks ◯ and ∘ indicate the positions of the pots for supplying the resin tablets. The ∘ mark shows the case where one resin tablet was supplied to one pot, and the ∘ mark shows the case where two resin tablets were supplied to one pot. As can be seen from these tables, by changing the combination of supplying resin tablets, it is possible to perform resin molding with a different amount of resin supplied in a common center block, and it is effective even for products with considerably different resin amounts. It becomes possible to use.

As shown in FIGS. 4 and 5, the lower through runner 16 communicating with the pot into which the resin tablet is put.
When b is provided so as to communicate with the upper through runner 18b, the extending end of the lower through runner 16b is extended at the overlapping portion with the upper through runner 18b in parallel with the longitudinal direction of the upper through runner, and the overlapping portion is By narrowing the resin passages by narrowing them, when the molten resin is pressure-fed to the upper through runners 18b, the resin is fed from the entire lower through runners 16b into the upper through runners 18b, and the There is also an effect that the resin can be injected almost at the same time.

As described above, the fact that the center block can be resin-molded in common allows the die replacement work when changing the product type to be completed by replacing only the cavity block, and therefore the device is extremely easy to handle. Has the effect of becoming. This is because when the center block is replaced every time the product type is switched, the plunger, the equal pressure unit, etc. must be replaced, and an extremely complicated replacement work is required. And, when the molding die is configured as in the above-mentioned embodiment, there is an effect that the center block can be made common and the range of types of objects of resin molding can be significantly expanded. There is an advantage that it can be effectively used for automation of the molding apparatus.

[0026]

As described above, according to the molding die of the present invention, the center block can be commonly used when resin-molding different products, and only the cavity block can be replaced. The molten resin can be effectively kneaded during molding to form a resin mold. Further, by disposing the lower through runner and the upper through runner so as to partially overlap with each other, the resin can be injected into each cavity of the cavity block substantially at the same time, and a well-balanced resin molding can be performed. In addition, when supplying resin tablets to the pot, by selecting the pot that supplies the resin tablets, it is possible to use the common center block for resin molding even when products with considerably different resin amounts are resin molded. It has a remarkable effect such as becoming.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a molding die according to the present invention.

FIG. 2 is an explanatory diagram showing configurations of a center block and a cavity block.

FIG. 3 is an explanatory diagram showing an arrangement of a lower through runner and an upper through runner.

FIG. 4 is an explanatory diagram showing an arrangement example of through runners when a resin tablet is selectively supplied to a pot.

FIG. 5 is an explanatory view showing another arrangement example of the through runners when the resin tablets are selectively supplied to the pot.

FIG. 6 is an explanatory diagram showing a conventional example of resin molding using a through runner.

FIG. 7 is an explanatory diagram showing a conventional example in which resin molding is performed using a through runner.

[Explanation of symbols]

 5 Center Block 9 Through Runner 10 Pot 12 Lower Mold Center Block 14 Upper Mold Center Block 16 Lower Mold Cavity Block 16a Cavity Recess 16b Lower Through Runner 16c Gate 18 Upper Mold Cavity Block 18b Upper Through Runner 20 Cavity 30 Lead Frame 32 Resin Tablet

Claims (2)

[Claims] 1. The center block is commonly used for different kinds of products by communicating through resin paths between resin paths in the middle of the resin paths that respectively connect the pot provided in the center block and the cavity of the cavity block. In the mold die made possible, the through runners are partially overlapped on the mold matching surfaces of the lower mold cavity block and the upper mold cavity block as a lower through runner and an upper through runner so that the resin path bends between the upper and lower molds. Molding die characterized by being provided as. 2. An upper through runner is provided so as to communicate with all the cavities provided in the lower mold cavity block, and a lower through runner is provided only in the pot provided with the resin tablet among the pots provided in the center block and the upper through runner. The mold die according to claim 1, wherein the lower through-runner is provided so as to extend in the longitudinal direction of the upper through-runner at the overlapping portion with the upper through-runner.