JPH04208421A - Transfer molding device - Google Patents

Abstract

PURPOSE:To fully remove resin burrs or resin tailings, which adhere to the tip part of a plunger by a method wherein air is blown from the neighborhood of a plunger, with which resin tablet in a pot is pressed, against the tip part of the plunger. CONSTITUTION:Resin tablet 4, which is made of thermosetting resin powder and put in a pot 3, is pressed with a plunger 5, which is lowered in the pot 3, so as to be flown in a cavity in order to form a resin molded body. An air blowing mechanism 8, which is attached to the transfer molding device concerned, is to blow air at any time against the tip part of a plunger 5 before its insertion in the pot 3 and equipped in the neighborhood of the plunger 5. Thus, the resin burrs or resin tailings, which adhere to the tip part of the plunger 5, can be fully removed.

Description

[Detailed Description of the Invention] [Summary] Regarding a transfer molding device used for resin sealing of resin-sealed semiconductor devices, a plunger that presses a resin tablet placed in a pot is used to remove resin attached to the tip of the plunger. The purpose of the present invention is to provide a transfer molding device that can sufficiently remove particles and resin residue, and is configured to include an air blow mechanism that blows air from the vicinity of the plunger toward the tip of the plunger. - The mechanism is formed of an annular pipe through which the plunger passes and introduces compressed air, and has a plurality of air outlets directed toward the plunger.

[Industrial application field]

The present invention relates to a transfer molding apparatus used for resin-sealing resin-sealed semiconductor devices.

As is well known, in assembling a resin-sealed semiconductor device, a semiconductor chip is mounted on a lead frame, and the semiconductor chip is encapsulated with resin using a transfer molding machine. When sealing with resin,
It is important to prevent foreign matter such as resin debris from entering the mold.

[Conventional technology]

FIGS. 3(a) and 3(b) are an overall side view and a side view of essential parts for explaining the transfer molding apparatus.

In the figure, the transfer molding apparatus has a pot 3 in an upper mold 1, and a molded body forming cavity and a resin flow path leading from the pot 3 to the cavity are provided at the mating surface of the upper mold 1 and the lower mold 2. A thermosetting resin molded body is formed using a molded mold. That is, the upper mold 1 and the lower mold 2 attached above and below are heated, the lower mold 2 is raised by the operation of the mold press 6, and the mold is clamped by pressing it against the upper mold 1, and then the thermosetting resin powder is placed in the pot 3. The plunger 5, which has been inserted downwardly into the pot 3 by the operation of the cylinder 7, presses the resin tablet 4, causing the resin to flow into the cavity and form a resin molded body.Then, the lower mold 2 is lowered to open the mold. This allows the resin molded body to be taken out. The plunger 5 rises and returns to its normal position when the mold is opened.

When resin-sealing a resin-sealed semiconductor device, the lead frame carrying the semiconductor chip is placed on the lower mold 2 with the semiconductor chip positioned in the cavity portion before mold clamping.

By the way, the upper mold 1 and the lower mold 2 after taking out the resin molded body
Resin particles made of hardened resin may remain on the mating surfaces. These foreign substances on the mating surfaces of the upper mold 1 and lower mold 2 may cause dents on the lead frame or cause resin leakage between the upper mold 1 and the lower mold 2 during the next molding. Since the resin in the resin flow path may cause incomplete filling of the cavity, it is removed by blowing air with a manually operated air gun before placing the lead frame.

In addition, resin particles and resin scum may adhere to the tip of the raised plunger 5, especially its side surface, due to the inflow into the clearance with the pot 3, and the resin particles and resin scum may also be peeled off and molded. If it gets into the mold, it will cause problems like the previous foreign matter, so it is removed by blowing air using the same air gun.

[Problem to be solved by the invention]

However, although the foreign matter remaining between the upper mold 1 and the lower mold 2 is sufficiently removed by the above-mentioned air blowing, the resin particles and resin scum attached to the tip of the plunger 5 cannot be removed by bringing the air gun close to the plunger 5. is difficult to remove sufficiently.

SUMMARY OF THE INVENTION An object of the present invention is to provide a transfer molding apparatus capable of sufficiently removing resin particles and resin debris adhering to the tip of the plunger 5.

[Means to solve the problem]

In order to achieve the above object, the transfer molding apparatus of the present invention includes a plunger for pressing a resin tablet placed in a pot, and a plunger for removing resin attached to the tip of the plunger from the vicinity of the plunger. 'It is characterized by being equipped with an air blow mechanism that blows air toward the tip. Preferably, the air blow mechanism is formed of an annular pipe through which the plunger passes and introduces compressed air, and has a plurality of air jet ports directed toward the plunger.

[For production]

The air blow mechanism blows air from the vicinity of the plunger corresponding to the plunger 5 described above toward the tip of the plunger, so that resin particles and resin debris attached to the tip of the plunger can be sufficiently removed. is possible. If a plurality of air outlets are provided in an annular shape as described above, air can be blown around the entire circumference of the plunger, making the removal more reliable.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 and 2. Figures 1 (a) and (b) are a side view and a bottom perspective view showing the main parts of the embodiment, and Figures 2 (a) and (b) are a side view and a bottom perspective view of the air blow mechanism in the embodiment. can be,
The same reference numerals indicate the same objects throughout the figures.

In FIGS. 1(a) and 1(b), this embodiment has an air blow mechanism 8 added to the transfer molding apparatus described above, and FIG. 1(a) is similar to FIG. 3(b). Correspondingly, FIG. 1(b) shows the upper mold 1 and the plunger 5 viewed diagonally from below.

The air blow mechanism 8 is used to blow air 9 at any time toward the tip of the plunger 5 before it is inserted into the bot 3, in place of the manually operated air gun described above.
Since the plunger 5 is provided near the plunger 5, the aforementioned resin debris and resin debris adhering to the tip of the plunger 5 can be sufficiently removed.

It is desirable to perform this air blowing immediately after the plunger 5 rises from the bot 3.

This is because the resin particles and resin scum are cooled before the plunger 5 is cooled and become easily peeled off.

When the resin particles and resin scum peeled off from the plunger 5 by this air blowing fall through the bot 3 onto the surface of the lower mold 2, they cause the above-mentioned inconvenience. This can be avoided by blowing air between the lower molds 2 after the air blowing by the air blowing mechanism 8.

Details of the air blow mechanism 8 are shown in FIGS. 2(a) and 2(b). That is, the air blow mechanism 8 is fixed to the surface on which the upper die 1 is attached, and is formed of a pipe which has an annular shape that passes through the plunger 5 and introduces compressed air from a compressed air supply pipe 10, and the air blow mechanism 8 is formed of a pipe that introduces compressed air from a compressed air supply pipe 10, and extends through the annular pipe at equal intervals. It has a plurality of air jet ports 8a directed toward the plunger 5 from the divided positions.

With this configuration, the air 9 can be blown around the entire circumference of the plunger 5, and the resin particles and resin scum can be surely removed.

Needless to explain again, the arrangement of the air blow mechanism as described above contributes to labor saving by reducing the number of worker steps, and also makes it easier to automate continuous molding operations. It is something that makes you

〔Effect of the invention〕

As explained above, according to the present invention, in a transfer molding apparatus used for resin-sealing a resin-sealed semiconductor device, etc., resin paris or resin particles attached to the tip of a plunger that presses a resin tablet placed in a bot can be used. It is now possible to sufficiently remove debris using the molding equipment itself, which reduces dents on the lead frame, resin leakage between the upper and lower molds, poor filling of the cavity, etc., and contributes to labor savings for workers. This also has the effect of facilitating automation of continuous molding operations.

[Brief explanation of the drawing]

Figures 1 (a) and (b) are a side view and a bottom perspective view showing the main parts of the embodiment; Figures 2 (a) and (b) are a side view and a bottom view of the air blow mechanism in the embodiment; 3(a) and 3(b) are an overall side view and a side view of essential parts for explaining the transfer molding apparatus. In the figure, 1 is an upper mold, 2 is a lower mold, 3 is a bot, 4 is a resin tablet, 5 is a plunger, 6 is a mold breath, 7 is a cylinder, 8 is an air blow mechanism, 8a is an air outlet, 9 is an air , 10 is a compressed air supply pipe. 1' upper mold 2° lower mold 3: pot 4' diarrhea 1 tablet S nibranshima 8: air blow surface 9' side view showing the main parts of the air example Bottom perspective view showing main parts Figure 1 (Part 2) 5. Plunge-C? 8: Air blow rock %: Air outlet 9・Air 10゛ and day EJW air eye 2N lost #! fIJ + Koke 6 Airflow Isohashi Flight] Top view and bottom surface (company) 2nd recess 5: Plunger 6 Mold brace 7: Plunge transfer molding table! A prisoner was paraded inside the meeting to give an explanation.
Figure $3 (Part 1)

Claims (1)

[Claims] 1) A plunger that presses a resin tablet placed in a pot, and air is blown from near the plunger toward the tip of the plunger so as to remove resin attached to the tip of the plunger. A transfer molding device comprising an air blow mechanism. 2) The transfer device according to claim 1, wherein the air blow mechanism is formed of an annular pipe through which the plunger passes and introduces compressed air, and has a plurality of air jet ports directed toward the plunger. Molding equipment.