JPH05245844A - Resin-encapsulation mold with venting function - Google Patents

Abstract

PURPOSE:To make an encapsulation device smaller and lighter in weight by compressing voids of air drawn into resin due to the flow of the resin under low injection pressure when resin-encapsulation is carried out by a transfer mold method. CONSTITUTION:Air vents each extending from each cavity 4 are connected with one another in an upper and lower mold 7, 8 to form a connected vent 6. An exhaust port 10 is provided on one end of the vent 6 and an exhaust pump 12 is connected to the port 10 to forcibly vent the gas from the cavities 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-sealing die having an exhaust function, and more particularly to a resin-sealing die for resin-sealing by transfer molding using a thermosetting resin.

[0002]

2. Description of the Related Art A conventional resin molding die is shown in FIG. 2 (a), which is a bottom view of the upper die, FIG. 2 (b) is a top view of the lower die, and FIG.
As shown in the vertical cross-sectional view of FIG. 1, a pot for charging resin 1, a cull 2, a runner serving as a resin flow path 3, a cavity 4 for forming a product 4, a gate 5 connecting the runner 3 and the cavity 4,
It has an air vent 6 which serves as a passage for the air in the mold. The mold itself is divided into an upper mold 7 and a lower mold 8.

Next, the operation of the mold will be described. After the upper mold 7 and the lower mold 8 are clamped, the resin is poured from the pot 1,
When the plunger head 9 is lowered, the resin flows from the cull 2 to the runner 3 and the gate 5, and each cavity 4
Fill inside. At this time, the air inside the runner 3 or the cavity 4 is naturally exhausted from the respective air vents 6 to the outside of the mold as the resin is filled.

[0004]

In this conventional mold for resin encapsulation, the air in the runner and the cavity is naturally exhausted by the injected resin, but the air entrained by the resin in the runner and the gate is air vented. There is a problem in that it is difficult to exhaust from the inside and remains in the cavity as a void. In addition, if the injection pressure is increased to compress the remaining voids, a high mold clamping pressure is required to reduce the occurrence of thin flashes that accompany the injection pressure. There was also a problem that it hindered size and weight reduction.

[0005]

According to the resin sealing mold of the present invention, the air vents from the respective cavities are collectively connected in the mold, and the connected air vents are provided with exhaust ports to provide an exhaust pump outside the mold. It has the function of forced exhaust and ventilation.

[0006]

The present invention will be described below with reference to the drawings.

1A and 1B are views showing a resin-sealing mold according to an embodiment of the present invention. FIG. 1A is a bottom view of the upper mold, FIG. 1B is a top view of the lower mold, and FIG. (C) is a vertical cross-sectional view of the mold.

The structure of the pot 1, cull 2, runner 3, cavity 4, gate 5, upper die 7, lower die 8 and plunger head 9 is the same as that of the conventional die, but the air vent 6 is used.
Unlike the conventional mold, does not extend to the outside of the mold individually, but is connected inside the mold, and is sealed when the mold is clamped. The exhaust port 1 is provided at one end of the air vent 6.
0 is provided and is connected to an exhaust pump 12 outside the mold through an exhaust duct 11 inside the mold. After the mold is clamped, the resin is put into the pot 1, the plunger head 9 is lowered, and the injection is started. It is exhausted from 11 onwards. Then, at the same time as the injection is completed, the exhaust is also completed, and the void left in the cavity is compressed by the holding pressure of the plunger head after the injection.

[0009]

As described above, according to the present invention, by adding the function of forcibly exhausting from the air vent, even if the resin flowing in the mold entrains air, the entrained air itself is a low pressure. There is an effect that the void can be sufficiently compressed with a low injection pressure. As a result, a high mold clamping pressure is not required, so that the resin sealing device can be made smaller and lighter.

[Brief description of drawings]

1A and 1B are views showing an embodiment of the present invention, in which FIG. 1A is a bottom view of an upper mold, FIG. 1B is a top view of a lower mold, and FIG. 1C is a vertical cross section of a mold. It is a figure.

FIG. 2 is a view showing a conventional resin-sealing mold, and FIG.
Is a bottom view of the upper die, FIG. 2B is a top view of the lower die, and FIG. 1C is a vertical sectional view of the die.

[Explanation of symbols]

 1 Pot 2 Cull 3 Runner 4 Cavity 5 Gate 6 Air Vent 7 Upper Mold 8 Lower Mold 9 Plunger Head 10 Exhaust Port 11 Exhaust Duct 12 Exhaust Pump

Claims (1)

[Claims] 1. A mold for resin-sealing with an exhaust function, wherein air vents from respective cavities are collectively connected in a mold, and an exhaust port is provided at one end of the connected air vent to connect to an exhaust pump. .