JPH06246768A - Resin mold - Google Patents

Abstract

PURPOSE:To effectively discharge unnecessary cured resin of a gate, etc., in a resin mold using a vertical gate. CONSTITUTION:Molten resin is fed under pressure by a plunger 18, filled in a cavity 14, cured, the plunger 18 is then drawn from a pot 16, cured resin 26 is adhered to a pressing end face of the plunger 18, and unnecessary resin 26 is discharged. A slide plunger 22 is so provided at an outer periphery of an end of the plunger 18 as to be movable in a telescopic direction of the plunger 18. When the plunger 18 is drawn after the resin is filled, and the plunger 22 is brought into contact with a stationary member 28 disposed on the drawing position. When the plunger 18 is further moved in the drawing direction thereby to allow the plunger 22 to push the resin 26 in a protruding direction, thereby peeling to remove the resin from the plunger 18.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art When a lead frame or a TAB tape on which a semiconductor chip is mounted is resin-molded, these molded products are clamped with a molding die and the cavity is filled with resin. In the transfer molding method, a resin tablet is supplied to a pot, and the resin melted in the pot is pressure-fed by a plunger to be filled in the cavity to be molded into a predetermined shape. In the conventional transfer molding method, a so-called side gate method is generally used in which a resin path leading from the pot to the cavity is provided on the parting surface of the mold and the resin is injected from the side surface of the cavity.

In the conventional transfer molding method, FIG.
As shown in Fig. 4, the plunger 4 is pushed to fill the resin in the cavity 5, and after the resin 6 is cured, the plunger 4
Pull back. Since the mold die 7 is still clamped, the plunger 4 is separated from the cured resin by pulling back the plunger 4 and the mold die 7 is removed.
The cured resin remains on the surface. When the mold is opened, the cured resin remaining in the mold is released from the mold together with the article to be molded by an ejector pin or the like provided on the mold side and removed.

[0004]

As described above, in the general resin molding apparatus, when the plunger returns, the effect resin remains on the mold side, so that the plunger itself has a function of removing the cured resin. Absent. In extrusion molding, etc., when the plunger is pulled out of the mold, the cured resin after resin filling adheres to the pressing end face of the plunger and is pulled out, so the cured resin must be removed from the end face of the plunger. However, in this case as well, the cured resin is manually peeled and removed by a hammer or the like, and the plunger itself does not have a function of removing the cured resin.

By the way, recently, a product having an extremely thin resin package portion has been produced as in the case of directly resin-molding a TAB tape. Therefore, there is a problem in molding such as resin unfilling or void formation. Is occurring. Therefore, as a method of improving the resin filling property and enabling reliable resin molding, a method of providing a vertical gate perpendicular to the outer surface of the package and filling the resin is being studied. In the resin molding method using the vertical gate, the cured resin after resin molding adheres to the end surface of the plunger and is taken out, so that the method for removing the cured resin poses a problem. It is an object of the present invention to provide a resin molding apparatus that can easily separate and remove the cured resin that has adhered to the plunger and is taken out from the plunger.

[0006]

The present invention has the following constitution in order to achieve the above object. That is, in a resin mold device that pumps molten resin by a plunger to fill the cavity with resin, pulls out the plunger from the pot after the resin has hardened, and adheres the cured resin to the pressing end surface of the plunger to discharge unnecessary resin. The plunger is provided with a pusher movable in the forward and backward directions with respect to the plunger and capable of abutting the end face against the resin adhering to the push end face of the plunger. It is provided on the drawer side that is pulled out to the outside, and the pusher or the support of the pusher comes into contact with the pusher to stop the movement of the pusher, and the plunger is moved to relatively press the pusher against the plunger. It is characterized in that a fixing member for pushing the resin adhering to the end face in a direction of peeling is provided. Further, as the pushing body, a slide plunger is provided which is in sliding contact with the outer surface of the front end portion on the pushing end side of the plunger, and as the pushing body, an ejector pin protruding from the pushing end surface of the plunger is inserted. It is characterized in that it is arranged in the plunger.

[0007]

[Function] After the plunger is inserted into the pot and resin molding is performed, the plunger is pulled out to the outside of the pot.
At that time, the hardened resin adheres to the pressing end surface of the plunger and is pulled out, but when the plunger moves, the pushing member comes into contact with the fixed member located on the moving position and the movement is restricted, and the plunger is moved. By further moving, the pusher moves in the protruding direction relative to the plunger, and the resin adhering to the pressing end face of the plunger is pushed and removed in the peeling direction. A slide plunger or an ejector pin can be used as the pusher, and the slide plunger and the ejector pin are both pushed by the movement of the plunger to remove the resin adhering to the end face of the plunger.

[0008]

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. 1, 2, and 3 are explanatory views showing the configuration and operation of an embodiment of a resin molding apparatus according to the present invention. The resin molding apparatus of the embodiment is a vertical gate type apparatus in which a gate is provided in the direction perpendicular to the cavity surface. In FIG. 1, 10a and 10b are an upper cavity block and a lower cavity block.
2a and 12b are an upper chase block and a lower chase block. Reference numeral 14 is a cavity for molding a molded product.

Cavity 1 of the upper chase block 12a
A pot 16 into which a resin tablet is placed above the position 4
To place. The pot 16 is provided so as to penetrate through the upper chase block 12a in the thickness direction, and a plunger 18 for pressure-feeding the molten resin is installed in the pot 16 so as to be freely inserted and withdrawn. Reference numeral 20 is a vertical gate that connects the pot 16 and the cavity 14. The vertical gate 20 is provided parallel to the mold opening / closing direction, that is, perpendicular to the cavity surface, and the gate end is opened on the top surface of the cavity and the tip end side communicating with the cavity 14 is formed in a tapered shape with a small diameter.

The plunger 18 pumps the molten resin to the cavity 14 side, and the check end groove 1 for adhering the cured resin after resin molding to the end face and pulling it out at its pressing end face.
8a is provided. Further, a slide plunger 22 is provided on the outer surface on the tip side of the plunger 18 concentrically with the plunger 18 so as to be slidable in the axial direction. The slide plunger 22 acts as a pusher for removing the resin attached to the end surface of the plunger 18. A flange 22a is provided around the base of the slide plunger 22, and a flange 19 that abuts the flange 22a is provided on the outer surface of the plunger 18.

The flange 22a is provided with a bolt 24 which extends through the through hole provided in the projecting edge 19 and extends toward the projecting edge 19 side.
The elastic spring is externally attached to the bolt 24 to form the flange 22a.
The ridge 19 is urged so as to always come into contact. The slide plunger 22 is set so that the end surface of the slide plunger 22 coincides with the position of the pressing end surface of the plunger 18 with the flange 22a and the projecting edge 19 in contact with each other.

Next, the resin molding operation of the resin molding apparatus of the above embodiment will be described. First, after the molded product is clamped by the upper cavity block 10a and the lower cavity block 10b, a resin tablet is put into the pot 16 with the plunger 18 pulled up above the pot 16, and the plunger 18 is placed in the pot 16. To enter.
The resin tablet is melted by the heat of the molding die, and the molten resin is pressure-fed by the plunger 18 to fill the cavity 14 with the resin from the vertical gate 20.

FIG. 1 shows a state in which the plunger 18 is lowered to the lowest point position. The flange 22a of the slide plunger 22 comes into contact with the projecting edge 18a, and the slide plunger 22 moves down into the pot 16 together with the plunger 18 to press the resin. The molten resin is completely filled in the cavity 14 and remains at the bottoms of the vertical gate 14 and the pot 16. This pressure is maintained for a certain period of time to cure the resin, and then the plunger 18 is raised to the outside of the pot 16. The resin 26 that has hardened at the bottom of the pot 16 is taken out by adhering to the pressing end surface of the plunger 18 by pulling up the plunger 18, and at the vertical gate 20 portion, the hardened resin is hardened at the boundary between the cavity surface and the vertical gate 20. It is divided and taken out together with the resin 26 (FIG. 2). The check groove 18a provided on the end surface of the plunger 19 is effective for surely adhering the resin 26 to the end surface of the plunger 18.

As shown in FIG. 3, the plunger 18 rises to a position where the flange 22a of the slide plunger 22 comes into contact with a fixed plate 28 which is a fixed member fixed to the side of the plunger 18 at a position above the mold. Stop climbing movement. The fixing plate 28 contacts only the flange 22a when the plunger 18 is lifted, and the fixing edge 28 of the plunger 18
Is a hole having a diameter size to be passed. That is, the outer diameter size of the projecting edge 19 is set to be slightly smaller than the outer diameter of the flange 22a, and only the flange 22a abuts the fixed plate 28 when the plunger 18 moves up.

When the flange 22a comes into contact with the fixed plate 28, the elastic spring mounted on the bolt 24 is compressed and the slide plunger 22 is pushed down relative to the plunger 18. Since the outer peripheral edge portion of the resin 26 adheres to the end surface of the slide plunger 22, the outer peripheral edge of the resin 26 is pressed by pushing down the slide plunger 22, and the resin 26 is separated from the end surface of the plunger 18. To fall. In this way, by raising the plunger 18 from inside the pot 16 to the position where the flange 22a abuts the fixing plate 28, the cured resin is taken out from the pot 16 and the vertical gate 20 to remove the unnecessary resin 26 from the plunger 18. The operation of doing can be performed as a series of operations.

When the resin 26 is peeled off from the plunger 18 and dropped, the resin receiver 30 is set to discharge the resin 26 to the outside. Plunger 18
During the peeling and removing operation of the resin 26, the mold is opened and the molded product is taken out. Then, when a new molded product is set and the next resin molding operation becomes possible, the plunger 18 is lowered again into the pot 16 to start the resin filling operation. When the contact between the fixing plate 28 and the flange 22a is released, the flange 22a and the projecting edge 19 contact with each other by the elastic spring attached to the bolt 24, and the molten resin is automatically pumped.

The resin molding apparatus of the above-mentioned embodiment discharges unnecessary resin from the mold by lifting and lowering the plunger 18, and removes the resin adhering to the plunger 18, as shown in FIG. FIG. 5 also shows another embodiment of the resin molding apparatus that performs the same operation by the lifting and lowering operation of the plunger 18. In the resin molding apparatus of this embodiment, the movable flange 32 is provided movably in the advancing / retreating direction with respect to the plunger 18, and the plunger 18
An ejector pin 34 is provided inside the container so as to be movable in the advancing / retreating direction of the plunger 18 and capable of projecting a tip from the pressing end surface of the plunger 18, and the base of the ejector pin 34 is connected to the movable flange 32.

The movable flange 32 is urged upward by a resilient spring 36 externally fitted to the ejector pin 34,
The upper position is regulated by abutting the stopper 38. The ejector pin 34 has its tip end position retracted from the end face of the plunger 18 with the movable flange 32 in the upper position, and the check groove 18a communicates from the retracted position to the end face of the plunger 18.

FIG. 4 shows a state where the plunger 18 is inserted into the pot 16 and the molten resin is filled in the pot 16 in the cavity 14. The resin is injected into the cavity 14 via the vertical gate 20 and slightly remains in the pot 16. After the resin is hardened, the plunger 18 is lifted so that the resin 26 adheres to the end surface of the plunger 18 and is taken out. The plunger 18 further rises to bring the upper surface of the movable flange 32 into contact with the fixed plate 28, and by further raising the plunger 18, the movable flange 32 is pushed down against the elastic spring 36, and with this, the ejector. The pin 34 is pushed down.

Since the tip end surface of the ejector pin 34 is in contact with the resin 26 at the check groove 18a, the resin 26 is peeled off and removed from the end surface of the plunger 18 by pushing down the ejector pin 34. FIG. 5 shows a state in which the ejector pin 34 projects from the end surface of the plunger 18 and the resin is peeled off from the end surface of the plunger 18. When the plunger 18 is lowered after peeling off the resin 26, the movable flange 32 is pushed up by the elastic force of the elastic spring 36, and the ejector pin 34 retracts to the retracted position. In this way, the next resin filling operation by the plunger 18 becomes possible.

FIG. 6 shows still another embodiment of the resin molding device. In this embodiment, the slide plunger 22 is slidably provided at the tip of the plunger 16 as in the first embodiment. However, unlike the first embodiment, the slide plunger 22 is entirely in the upper mold. Is configured to enter. Further, at the pull-out position of the slide plunger 22, a locate ring 40 is fixed on the upper die, and a plunger guide ring 42 is further fixed. The plunger guide ring 42 is brought into contact with the peripheral edge of the flange of the slide plunger 22 when the plunger 18 is lifted, and the resin 26 is transferred to the plunger 1 as in the above-described embodiment.
It is for peeling and removing from the end face of No. 8.

FIG. 6 shows a state where the plunger 18 is filled with the resin and a state where the plunger 18 is moved to the upper position and the resin 26 is peeled and removed. A resin receiver that receives the resin 26 that has been removed from the plunger 18 and dropped can be inserted from the side of the locate ring 40.
The resin discharging operation is performed in accordance with the resin 26 removing operation.
Reference numeral 44 denotes an upper platen of the press, and FIG. 6 shows a state in which the upper die, the plunger 16, the plunger guide ring 42 and the like are attached to the platen 44.

Each of the resin molding apparatuses of the above-mentioned embodiments is a type of apparatus that adheres the cured resin in the pot to the plunger and discharges it when the plunger 18 moves back, and is a vertical gate type resin molding apparatus. Can be suitably applied to. In the present invention, the unnecessary resin is removed by utilizing the movement of the plunger, so that the unnecessary resin can be removed easily and efficiently. Particularly, since the slide plunger 22 or the ejector pin 34 is provided on the plunger 18 to positively peel off the resin 26, it is possible to reliably remove the unnecessary resin.

Further, since the resin 26 can be reliably removed by the slide plunger 22, the resin can be removed even if a check groove is provided on the pressing end surface of the plunger 18 as in the embodiment. It has become possible to improve the adhesion of the resin on the end face of the and secure the discharge of the unnecessary resin. The resin molding apparatus according to the present invention can be applied to a molding die having a single pot and a molding die having a plurality of pots. Further, it can be similarly applied to a molding die of a type in which a plurality of vertical gates are extended from one pot. When a plurality of vertical gates are provided in one pot, it is possible to connect separate cavities to each vertical gate and to fill the plurality of cavities with resin at one time. Further, in the above-mentioned embodiment, the resin molding device by the vertical gate method is described as an example of the resin molding device in which the unnecessary resin is attached to the plunger 18 and taken out, but the same applies to the resin molding device by the extrusion molding other than the vertical gate method. It goes without saying that it can be applied to.

[0025]

As described above, according to the resin molding apparatus of the present invention, when the plunger is provided with the pusher, the pusher comes into contact with the fixed member when the plunger moves, and the pusher is attached to the plunger. By being configured to project, unnecessary resin attached to the plunger and discharged can be reliably removed, and the discharge of unnecessary resin can be automated and efficient resin molding can be performed. It produces a remarkable effect such as being able to.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a state in which a cavity is filled with resin in an embodiment of a resin molding device.

FIG. 2 is an explanatory view showing a state in which a plunger is lifted and a resin required is taken out.

FIG. 3 is an explanatory diagram showing a state in which unnecessary resin is peeled off from the plunger.

FIG. 4 is an explanatory diagram showing a state in which a cavity is filled with resin in another embodiment of the resin molding apparatus.

FIG. 5 is an explanatory view of a state in which an unnecessary resin is peeled and removed from the plunger by raising the plunger.

FIG. 6 is an explanatory view showing still another embodiment of the resin molding device.

FIG. 7 is an explanatory view showing a state in which a cavity is filled with resin by a plunger in a conventional resin molding device.

[Explanation of symbols]

 10a Upper cavity block 10b Lower cavity block 12a Upper chase block 12b Lower chase block 14 Cavity 16 Pot 18 Plunger 18a Check groove 19 Projection edge 20 Vertical gate 22 Slide plunger 22a Flange 26 Resin 28 Fixing plate 32 Movable flange 34 Ejector pin 36 Repulsion spring 38 Stopper 40 Locate ring 42 Plunger guide ring 44 Platen

Claims (3)

[Claims] 1. A resin which discharges unnecessary resin by pumping molten resin by a plunger to fill the cavity with resin, hardening the resin, and then pulling out the plunger from the pot and attaching the cured resin to the pressing end surface of the plunger. In the molding apparatus, the plunger is provided with a pusher movable in the advancing / retreating direction with respect to the plunger and capable of abutting the end face against the resin adhering to the push end face of the plunger. Is provided on the drawer side that is pulled out to the outside of the pot, the pusher or the support of the pusher comes into contact with the pusher to stop the movement of the pusher, and the plunger is moved to relatively plan the pusher. A resin molding device characterized in that a fixing member for pushing the resin attached to the pressing end surface of the jar is provided in a direction for peeling the resin. . 2. The resin molding apparatus according to claim 1, wherein a slide plunger that is in sliding contact with the outer surface of the front end portion of the plunger on the pressing end side is provided as the pushing body. 3. The resin molding apparatus according to claim 1, wherein an ejector pin projecting from the pressing end surface of the plunger is provided in the plunger as the pusher.