JPH0371817A - Transfer mold - Google Patents

Abstract

PURPOSE:To simplify the structure of a top force by a method wherein a resin well part and a molding pressure controlling hole, the tip of which is opened in the resin well part and in which a molding pressure controlling plunger is mounted, are provided on a bottom force and the molding pressure controlling plunger is energized by the predetermined pressure to the resin well part side. CONSTITUTION:By moving a transfer plunger 3 upwards, the transfer of molding material is proceeded, resulting in filling molding material 10 in a cavity 4. At this time, when the amount of molding material charged in a pot 5 is too much, molding pressure results in exceeding the predetermined pressure. However, said pressure is applied through the molding material 10 in a resin well part 6 also to a molding pressure controlling plunger 8. When said pressure exceeds the springy force developed by an elastic body 27, the molding pressure controlling plunger 8 retreats by the action of said pressure through the compression of the elastic body 27, resulting in absorbing the excess molding material 10 in a molding pressure controlling hole 7. Accordingly, each cavity 4 can be prevented from being applied by abnormal molding pressure.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a multi-blank one-type transfer molding mold used for sealing molding of electronic parts, in particular, molding pressure adjustment 8! It is related to the structure.

[Conventional technology]

Transformer 7T, - In the molding mold, a pot for charging the molding material is formed on the upper surface of the lower mold, and the content in the pot is moved upward by a transfer plunger provided through the lower mold. Molding can be carried out by pressurizing the molding material and transferring and filling each cavity from the pot via the runner. In such transfer molding molds, if there is variation in the amount of molding material charged into the pot, there will be variation in the amount of molding material filled into the cavity, especially if the amount of molding material charged is excessive. If this happens, excessive molding pressure will be applied to the sensitive electronic components set in the cavity for sealing, and there is a risk that the electronic components will be damaged. Therefore, it has been considered to provide a molding pressure adjustment fill so that the molding pressure remains constant even if the amount of molding material input into the pot is excessive.
It is provided in Japanese Patent Application No. 423 and Japanese Patent Application Laid-Open No. 60-214916. In these products, a molding pressure adjustment valve is provided in the upper mold at a position corresponding to the pot, and the molding pressure adjustment valve is biased with a predetermined pressure by a spring, oil pressure, etc., thereby forming a molding pressure adjustment W1 structure. That's what I do. When the amount of molding material put into the pot is excessive, the molding pressure is 14V when pressurized by the transfer plunger! By retracting the valve, excessive molding pressure is absorbed and the molding pressure is adjusted to a constant level.

[Problem to be solved by the invention]

However, in the above-mentioned Japanese Patent Application Laid-Open No. 60-149423 and No. 60-214916, the molding pressure is set to 11g in the upper mold, and the molding pressure is adjusted by installing a valve in the upper mold. However, there was a problem in that the structure of the upper mold, which can generally be formed into a simple structure, became complicated. The present invention has been made in view of the above points, and it is an object of the present invention to provide a transfer molding mold that can be provided with a molding pressure adjustment mechanism without complicating the structure of the upper mold. be. [Means for Solving Problem 11] The present invention provides a method in which a transfer plunger 3 for pressurizing the molding material is installed in a vertical hole 2 provided in a lower mold 1, and an upper end surface of the transfer plunger 3 in the vertical hole 1 is provided. In a transfer molding mold in which the upper part is formed as a pot 5 for introducing molding material which communicates with the cavity 4, a bot 5 is placed in the lower mold 1.
A resin reservoir 6 is provided which communicates with the resin reservoir 6, and a pressure adjustment hole 7 whose tip is opened in the resin reservoir 6 is provided in the lower mold 1, and a molding pressure adjustment blank layer 8 is installed in the molding pressure adjustment hole 7. This is characterized in that the pressure adjusting planar 8 is urged against the resin reservoir portion 61Il at a predetermined pressure.

[For use]

In the present invention, the lower mold 1 is provided with a resin reservoir 6 that communicates with the bot 5, and the lower mold 1 is provided with a molding pressure adjustment hole 7 whose tip is open in the resin reservoir 6. Since the molding pressure adjustment plunger 8 is installed in the molding pressure adjustment hole 7, the molding that is performed by the resin reservoir 6, the molding pressure adjustment hole 7, and the molding pressure adjustment plunger 8 is performed. The pressure adjustment mechanism can be incorporated into the lower mold 1, and there is no need to attach a molding pressure adjustment mechanism to the upper mold 9.

【Example】

The present invention will be explained in detail below with reference to Examples. As shown in FIG. 1, the lower mold 1 is mounted on a lower mounting plate 16 via a spacer block 15, and is provided with vertical holes 2 that pass through it vertically at a plurality of locations. A head portion 3a of a transfer plunger 3 is inserted and attached into this vertical hole 2, and the lower end portion of the transfer plunger 3 that protrudes downward from the lower mold 1 is coupled and fixed to a plunger drive plate 17. be. The upper part of the vertical hole 2, that is, the upper side of the upper end surface of the transfer plunger 3 is shaped as a bot 5 that opens at the upper surface of the lower mold 1, and each bot 5 has a runner 18 as shown in FIG. .18... to a plurality of cavity recesses 19, 19...°. *Octopus runner 18 and cavity recess 1
Effect turbines 20, 20... are provided penetrating the lower mold 1 so as to correspond to 9, and the lower end of each effect turbine 20, 20... is an ejector plate 21.
It is fixed and bonded to it. Further, the lower mold 1 is formed with a resin reservoir 6 having an open top surface and communicating with the bot 5 via a gummy runner 29, and a molding pressure adjustment hole 7 opened at the bottom of the resin reservoir 6. is bored in the lower mold 1. The lower part of the molding pressure adjustment hole 7 is formed as a biasing tool storage chamber 26, and by attaching the lower plate 30 to the lower surface of the lower mold 1, the lower opening of the biasing tool storage chamber 26 is closed. That's how it is. A molding pressure adjustment plunger 8 is installed in the molding pressure adjustment hole, and a locking flange 25 formed at the rear end of the molding pressure adjustment plunger 8 is engaged with the stepped portion 26m of the biasing tool storage chamber 26. I'm trying to stop it. In addition, an elastic body 2 such as a spring as a biasing means is provided in the biasing device storage chamber 26.
7 is attached, press the rear end of the molding pressure adjustment buffing jar 8 with a predetermined pressure to move the molding pressure l! to the resin reservoir 6 side! This is the spring biasing of the adjustment branyard 8. As the biasing means, in addition to the elastic body 27 such as a spring, hydraulic pressure, pneumatic pressure, etc. can also be used. On the other hand, the upper mold 9 is attached to the ball mounting plate 22 and arranged above the lower mold 1, and is provided so as to protrude downward, but the id bin 23 is inserted into the id hole 24 of the lower mold 1. In this way, the upper mold 9 and the lower mold 1 are clamped together. By clamping the molds in this manner, the upper surface opening of the pot 5 and the upper surface opening of the resin reservoir 6 are closed on the lower surface of the upper mold 9, and the cavity 4 is formed in the cavity recess 19. Lower mold 1 and upper mold 9
The mold can be closed and opened by moving one or both of them up and down. However, in the 7T-molding mold with a transformer formed as described above, the mold is opened and the molding material 10 is put into each pot 5, and then the mold is clamped, and the cylinder is driven by a hydraulic device and a connecting rod 28. When the plate 17 is driven to move the transfer plunger 3 upward as shown in FIG. 3, the molding material 10 in the pot 5 is pressurized by the transfer plunger 3 and transferred from the runner 18 to the cavity 4. Filling of the molding material 10 into each cavity 4 is started. At this time, a part of the molding material 10 in the pot 5 also flows into the resin reservoir 6 through the dummy runner 29. Then, the transfer plunger 3 is further moved upward to further transfer the molding material 10, and the molding material 10 is filled into the cavity 4 as shown in FIG. At this time, if the amount of molding material 10 charged into the pot 5 is too large, the molding pressure will exceed a predetermined pressure;
It also acts on the molding pressure adjusting plunger 8 through the molding material 10 inside. When this pressure exceeds the elastic force of the elastic body 27, the molding pressure adjusting plunger 8 is moved by the elastic body 27.
The molding material 10 is moved back while being compressed, and the excess molding material 10 is collected in the molding pressure adjustment hole 7 as shown in FIG. Therefore, it is important to prevent abnormal molding pressure from being applied to each cavity 4, and avoid excessive molding on sensitive electronic components set in the cavity 4, such as when sealing electronic components. This can prevent damage caused by pressure. After the molding is completed, the mold is opened and the ejector plate 21 is operated to move the ejector turbine 20 upward, so that the molded product can be ejected from the cavity recess 19 of the lower mold 1 and removed from the mold. Effect of the Invention 1 As described above, in the present invention, the lower mold is provided with a resin reservoir that communicates with the pot, and the lower mold is provided with a molding pressure adjustment hole whose tip is open in the resin reservoir. In addition to providing molding pressure 11
1g! Attach the molding pressure adjustment blanker inside the tag and molding pressure lI! Since the adjustment blanker is biased toward the resin reservoir side with a predetermined pressure, the molding pressure W4! I
The Brannoyer can be installed in the lower mold, and the molding pressure adjusting mechanism can be incorporated in the lower mold.The molding pressure can be adjusted in the upper mold! It is possible to simplify the structure of the upper mold by eliminating the need to install an adjustment mechanism.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention taken along the line A-AM in FIG. FIG. 3 is a cross-sectional view of the same molded state taken along line A-AM in FIG. 2; 1 is the lower mold, 2 is the vertical hole, 3 is the transfer plunger 4 is the cavity, 5 is the pot, 6 is the resin reservoir, 7 is the molding pressure l
Il adjustment hole, 8 is a molding pressure adjustment plunger 9 is an upper mold, 1
0 is the molding material.

Claims (1)

[Claims] (1) A transfer plunger for pressurizing molding material is installed in the vertical hole provided in the lower mold, and the portion above the upper end surface of the transfer plunger in the vertical hole is used as a pot for introducing molding material that communicates with the cavity. In the formed transfer molding mold, a resin reservoir part communicating with the pot is provided in the lower mold, a pressure adjustment hole whose tip is open in the resin reservoir part is provided in the lower mold, and a molding pressure adjustment hole is provided in the molding pressure adjustment hole. A transfer molding mold characterized in that an adjustment plunger is attached and the molding pressure adjustment plunger is biased toward the resin reservoir side with a predetermined pressure.