JP2006062198A - Resin molding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin molding apparatus which can mold a resin while preventing resin unpacking and void occurrence by making a resin flow in a cavity be balanced well. <P>SOLUTION: In the resin molding apparatus for molding the resin by clamping an article 10 to be molded by an upper mold 20 and a lower mold 30 and packing the resin from a pot 32 into cavities 24a and 24b, gate pieces 25a, 25b, 35a, and 35b movable in the mold opening/closing direction are set at positions adjacent to the cavities 24a and 24b of the upper mold 20 and the lower mold 30, and gate piece moving means 27a, 27b, 37a, and 37b which regulate the positions in the mold opening/closing direction of the gate pieces set in the upper mold 20 and the lower mold 30 and the spaces between the contact end surfaces of the gate pieces are set. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a resin molding apparatus, and more particularly to a resin molding apparatus that performs resin molding by a transfer molding method.

In the transfer molding method used for resin molding of semiconductor devices or the like, resin molding is performed by extruding a resin melted in a pot with a plunger and filling the cavity with resin through a cull and a runner. The connection portion between the runner and the cavity is formed as a gate with a narrowed flow path, and the resin passes through the gate and is filled into the cavity.
In the conventional semiconductor device, since the thickness of the package is relatively thick, the resin flowability (fillability) in the cavity at the time of resin filling was not so much a problem, but when the thickness of the package is thin, In addition, when the cavity depth is different between the upper mold and the lower mold, the resin flowability becomes unbalanced, the resin flowability in the cavity deteriorates, and the resin is not filled or has voids. It has occurred.

There has been considered a method of improving the flowability and filling performance of the resin in the cavity by devising the configuration of the gate. For example, when a resin is injected into a cavity using a movable gate, the gate is widened, and after the resin is injected into the cavity, the resin is molded so that the gate is narrowed to a predetermined interval (Patent Document). 1, see Patent Document 2).
JP-A-5-267374 Japanese Patent Laid-Open No. 11-284002

  The method of resin molding by adjusting the opening amount of the gate when the resin is filled in the cavity can prevent the resin from entraining air at the gate portion, and can prevent the occurrence of voids in the resin mold portion. It has the effect of balancing the flowability of the resin in the cavity and preventing unfilling of the resin. However, if a molded product with a plurality of parts mounted on the substrate or a large-sized molded product with a plurality of irregularly shaped parts arranged in an appropriate manner is molded with resin, the gate opening There is a problem that an accurate resin molding cannot be performed by an adjustment method of adjusting the amount.

  Therefore, the present invention has been made to solve these problems, and the object of the present invention is to provide a solution in the cavity even when resin molding is performed on a molded product on which a plurality of components are mounted. It is an object of the present invention to provide a resin molding apparatus capable of performing resin molding by balancing the flowability of the resin and improving the filling property of the resin to prevent the resin from being unfilled and the generation of voids.

The present invention has the following configuration in order to achieve the above object.
That is, in a resin molding apparatus that clamps a product to be molded with an upper mold and a lower mold, fills a cavity with resin from a pot, and performs resin molding, the mold is positioned at a position adjacent to the cavity of the upper mold and the lower mold. A movable gate piece moving means provided with a movable gate piece movably in the opening and closing direction, and defining a distance between a position of the movable gate piece provided in the upper mold and the lower mold in the mold opening and closing direction and a contact end surface of the movable gate piece. Is provided.

Further, the movable gate piece is made of a plate-like or bar-like member, and a notch acting as a gate is provided on the contact end surface of the movable gate piece attached to the upper mold and / or the lower mold. To do.
The moving means is provided with a taper pin having a tip reaching from the side surface of the upper die and the lower die to the end surface opposite to the contact end surface of the movable gate piece, and the end surface of the movable gate piece and the tip of the taper pin Are formed in a tapered surface so as to be able to come into contact with each other, and driving means for moving the taper pins forward and backward to define the position of the movable gate piece in the mold opening / closing direction is provided. The taper pin is formed in a rod shape so as to be able to advance and retract, or is screwed into a mold so as to be able to advance and retract. As drive means for moving the taper pin forward and backward, an electric motor, a cylinder mechanism such as hydraulic pressure, or the like can be used.

Further, when the taper pin moves the taper pin into the mold by the driving means, the contact end surface of the movable gate piece moves in a direction approaching the opposing upper mold or lower mold, When the taper pin is moved out of the mold, the contact end surface of the movable gate piece is provided so as to move away from the opposing upper mold or lower mold.
Further, the movable gate piece is attached to the mold by being urged so that the contact end face moves away from the upper mold or the lower mold facing each other.

  According to the resin molding apparatus of the present invention, it is possible to perform resin molding by adjusting the position of the gate in the mold opening / closing direction and the interval between the contact end surfaces of the movable gate piece, and adjusting the gate position according to the product. In addition, resin molding can be performed by adjusting the opening cross-sectional area of the gate, and more accurate resin molding can be performed by balancing the flowability of the resin in the cavity.

(First embodiment)
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. FIG. 1 and FIG. 2 are plan views showing structural examples of an upper mold 20 and a lower mold 30 of a resin mold used in the resin mold apparatus according to the present invention.
The resin mold mold in the illustrated example is for resin molding one side of a molded article 10 formed in a flat plate shape, a cavity for resin sealing is provided in the upper mold 20, and the molded article is formed in the lower mold 30. A setting unit for setting 10 is provided.
In FIG. 1, a mold cull 22 is provided on the center block 21 of the upper mold 20 so as to face the pot 32 provided on the lower mold 30, and the cavity inserts 23 a and 23 b disposed on both sides of the center block 21 are respectively provided with cavities. 24a and 24b are formed, and movable gate pieces 25a and 25b are disposed between the end edge of the mold cull 22 and the side edges of the cavities 24a and 24b.

  The movable gate pieces 25a and 25b are formed in a flat block body and are housed in notches provided in the cavity inserts 23a and 23b, and are surrounded by the side surfaces of the center block 21 and the notches provided in the cavity inserts 23a and 23b. The sliding hole is slidably accommodated in the mold opening / closing direction. On the abutting end face facing the lower mold 30 of the movable gate pieces 25a, 25b, a recess that becomes the gate 26 when filling the cavities 24a, 24b with a resin is formed in a notch shape.

  As moving means for adjusting and defining the moving position of the movable gate pieces 25a and 25b in the mold opening / closing direction, in this embodiment, the upper end of the movable gate pieces 25a and 25b (on the side opposite to the contact end face) from the side surface of the upper mold 20. Taper pins 27a and 27b are inserted toward the surface), and the tip portions of the taper pins 27a and 27b where the tapered surfaces are formed are brought into contact with the end surfaces opposite to the contact end surfaces of the movable gate pieces 25a and 25b. Two taper pins 27a and 27b are arranged on each of the movable gate pieces 25a and 25b.

  As shown in FIG. 2, the lower mold 30 is provided with a pot 32 in the center block 31, and set portions 34 a and 34 b for setting the molded product 10 in inserts 33 a and 33 b arranged on both sides of the center block 31. Is provided. The set portions 34a and 34b are formed by matching the outer shape of the molded product 10 and forming the clamp surfaces of the inserts 33a and 33b in a concave shape.

In the lower mold 30, the movable gate pieces 35 a and 35 b are arranged along the both side surfaces of the center block 31 so as to face the movable gate pieces 25 a and 25 b provided on the upper mold 20. Similar to the movable gate pieces 25a and 25b, the movable gate pieces 35a and 35b are formed in a flat block body and are mounted in the notches provided in the inserts 33a and 33b so as to be slidable in the mold opening / closing direction. The In the movable gate pieces 35a and 35b of the embodiment, the contact end faces facing the movable gate pieces 25a and 25b are formed as simple flat surfaces, but the contact end faces of the movable gate pieces 35a and 35b are also provided on the contact end faces of the gate 26. A notch constituting the gate 26 can be formed corresponding to the position.
Similarly to the taper pins 27a and 27b provided on the upper die 20, the taper pins 37a and 37b are inserted from the side surface of the lower die 30 toward the end surface opposite to the contact end surface of the movable gate pieces 35a and 35b. Is done.

FIG. 3 shows the cross-sectional arrangement of the movable gate pieces 25a, 25b, 35a, 35b provided in the upper mold 20 and the lower mold 30, and the arrangement of the taper pins 27a, 27b, 37a, 37b and the like. Movable gate pieces 25a and 25b and movable gate pieces 35a and 35b are arranged so as to sandwich the center block 21 in the upper mold 20 and the center block 31 in the lower mold 30, respectively.
Further, the tip portions of the taper pins 27a, 27b, 37a and 37b are formed on the taper surfaces 271 and 371, and the upper end surfaces of the movable gate pieces 25a and 25b and the lower end surfaces of the movable gate pieces 35a and 35b are respectively tapered surfaces 271 and 371. Are formed on tapered surfaces 251 and 351 with which they abut.

The taper surface 271 formed on the taper pins 27a and 27b and the taper surface 251 formed on the movable gate pieces 25a and 25b are movable when the taper pins 27a and 27b move forward (to enter the center block 21). When the gate pieces 25a and 25b move toward the lower mold 30 and the taper pins 27a and 27b move backward, the movable gate pieces 25a and 25b move so as to move away from the lower mold 30.
Further, the taper surface 371 formed on the taper pins 37a and 37b and the taper surface 351 formed on the movable gate pieces 35a and 35b are such that when the taper pins 37a and 37b move forward, the movable gate pieces 35a and 35b are moved to the upper die 20. When the taper pins 37a and 37b move backward, the movable gate pieces 35a and 35b are provided so as to move away from the upper mold 20.

  FIG. 4 shows a state in which the movable gate piece 25a and the movable gate piece 35a of the resin mold are viewed from the front. In the upper mold 20, the movable gate holder 28 a is fixed above the movable gate piece 25 a, and a contraction spring 29 is mounted between the movable gate holder 28 a and the upper end surface of the movable gate piece 25 a, and the movable gate holder 28 a A taper pin 27a is interposed between the movable gate piece 25a. In the lower mold 30, a taper pin 37 a is interposed between the movable gate piece 35 a and the lower mold block 38.

  At the time of resin molding, as shown in FIG. 4, the end surfaces of the movable gate pieces 25a and 25b and the movable gate pieces 35a and 35b of the upper mold 20 and the lower mold 30 are abutted so that only the gate 26 is opened. The part where the movable gate pieces 25a, 25b and the end faces of the movable gate pieces 35a, 35b abut is the parting surface A of the gate piece. In FIG. 4, the parting surface A of the gate piece is in a state where it coincides with the upper surface position of the product 10.

Next, a resin molding method using the resin mold will be described.
The most characteristic configuration of the resin mold is that the movable gate pieces 25a and 25b and the movable gate pieces 35a and 35b provided on the upper mold 20 and the lower mold 30 are moved in the mold opening / closing direction as a pair. This is in that resin molding can be performed by adjusting the position of the gate 26 in the mold opening and closing direction.
FIG. 5 shows a state where the movable gate pieces 25a and 35a are moved in the mold opening / closing direction and the position of the gate 26 in the mold opening / closing direction is adjusted to perform resin molding. 5A shows a state where the gate 26 is moved downward, and FIG. 5B shows a state where the gate 26 is moved upward.

As described above, in the resin mold of the present embodiment, the taper pins 27a and 27b are engaged with the movable gate pieces 25a and 25b for the upper die 20, and the taper pins 37a and 37b are movable gate pieces 35a for the lower die 30. , 35b and the taper pins 27a, 27b and the taper pins 37a, 37b are moved forward and backward to move the movable gate pieces 25a, 25b and the movable gate pieces 35a, 35b up and down.
FIG. 5A shows the case where the taper pin 27a is advanced inward and the taper pin 37a is retracted outward. FIG. 5B shows the taper pin 27a retracted outward and the taper pin 37a inward. It is a case where it advances to. As described above, the moving positions of the movable gate piece 25a and the movable gate piece 35a in the vertical direction (mold opening / closing direction) can be appropriately adjusted according to the moving positions of the taper pins 27a and 37a.

FIG. 6 shows a state in which the position of the gate 26 in the mold opening / closing direction is moved by moving the taper pins 27a and 37a forward and backward as viewed from the front of the movable gate pieces 25a and 35a. 6A shows a state in which the gate 26 has moved upward, and FIG. 6B shows a state in which the gate 26 has moved downward.
In the upper mold 20, the movable gate piece 25 a is always suspended by the contraction spring 29, so that the movable gate piece 25 a moves up and down against the contraction force of the contraction spring 29.

As drive means for moving the taper pins 27a, 27b, 37a, 37b forward and backward, appropriate drive means such as an electric motor, a cylinder mechanism such as air or hydraulic pressure, and elastic means such as a spring can be used. By controlling these driving means, the forward and backward movement positions of the taper pins 27a to 37b can be adjusted, and the height position of the gate 26 can be adjusted.
In the above embodiment, the taper pins 27a, 27b, 37a, and 37b are formed in a rod shape so as to advance and retreat, but the main body of the taper pin is screwed into the upper mold 20 and the lower mold 30 with screws and attached. The taper pin can be moved forward and backward by rotating the taper pin around the axis. In this case, a tapered portion that is prevented from rotating may be provided at the tip of the taper pin.

5 and 6 show the case where the end surfaces of the movable gate piece 25a and the movable gate piece 35a are brought into contact with each other and resin-molded. However, in some cases, the end surfaces of the movable gate piece 25a and the movable gate piece 35a are separated from each other. It can also be resin-molded in the state.
FIG. 7 shows a state where the end surfaces of the movable gate piece 25a and the movable gate piece 35a are separated and resin-molded. The movable gate piece 25a provided on the upper mold 20 is in a position where the gate 26 has moved to a position above the upper surface of the molded article 10, and the movable gate piece 35a provided on the lower mold 30 has an end face position at the molded article. 10 substantially coincides with the top surface. As a result, a gap 26a is formed between the end surfaces of the movable gate piece 25a and the movable gate piece 35a, and a communication region (opening cross section) between the gate 26 and the gap 26a provided in the movable gate piece 25a substantially acts as a gate. .

As described above, when the resin molding is performed by separating the end surfaces of the movable gate piece 25a and the movable gate piece 35a, the entire width of the movable gate piece 25a becomes the gate region. Therefore, after the cavity 24a is filled with the resin, Then, at least one of the movable gate piece 25a or the movable gate piece 35a is moved to the other side, and finally the resin molding is performed in a state where the end surfaces of the movable gate piece 25a and the movable gate piece 35a are abutted.
In the case where the end surfaces of the movable gate pieces 25a and 35a of the upper mold 20 and the lower mold 30 are separated and resin-molded, it is not necessary to provide a notch for the gate 26 in the movable gate piece 25a of the upper mold 20, for example. It is also possible to form the end surfaces of the movable gate pieces 25a and 35a of both the upper mold 20 and the lower mold 30 in a flat surface.

  According to the resin mold apparatus of the present embodiment, the position of the gate 26 in the mold opening / closing direction is adjusted from the pot 32 to the cavities 24a and 24b with the molded product 10 clamped by the upper mold 20 and the lower mold 30. Resin is filled and resin molded. By setting the position of the gate 26 in the mold opening / closing direction so that the resin is filled in a balanced manner in the cavities 24a and 24b, the resin molding can be performed without causing the resin to be unfilled. Further, as shown in FIG. 7, by adjusting the opening cross-sectional area of the gate together with the arrangement position of the gate, the resin can be molded while preventing air from being caught in the resin.

In the resin mold used in the resin molding apparatus of the present embodiment, the movable gate pieces 25a, 25b, 35a, 35b are movable in the mold opening / closing direction. 25b, 35a, 35b need to be in a form that does not interfere.
FIG. 8 shows an example of a molded product 10 that is resin-molded using a resin mold. Fig.8 (a) shows the to-be-molded product 10 which mounted the circuit component 11 on the board | substrate 10a. At one side edge of the substrate 10a, a notch 10b is provided so as not to interfere with the movable gate pieces 25a and 35a when the article 10 is set on the lower mold 30. FIG. 8B shows a molded product obtained by resin-molding the molded product 10, and shows a state where the surface on which the circuit component 11 is mounted on the substrate 10 a is resin-sealed by the resin mold portion 12.

FIG. 8C shows another example of the molded article 10. The molded product 10 shown in this example is an example in which the insertion hole 10c for the movable gate piece is provided on the substrate 10a in a planar arrangement that does not interfere with the movable gate pieces 25a and 35a.
When using the resin mold die of this embodiment, the planar shape of the molded product 10 is provided so as not to interfere with the movable gate pieces 25a to 35b provided in the resin mold die. Accordingly, it is possible to set the position of the gate 26 in the mold opening / closing direction as appropriate and perform resin molding. Further, as shown in FIG. 8 (d), the movable gate can be formed by arranging the side surface of the cavity and the end of the molded product 10 so as to coincide with each other without providing a notch or the like in the substrate 10a. The piece and the molded product 10 can be resin-molded without interference.

(Second Embodiment)
FIGS. 9 and 10 show an example in which resin molding is performed using a resin mold mold that forms a plurality of resin mold sections in the product 10 as a second embodiment of the resin mold apparatus. FIG. 9 is a plan view of the upper mold 20, and FIG. 10 is a plan view of the lower mold 30. The resin mold mold according to the present embodiment is provided with four resin mold portions in the longitudinal direction of the molded article 10, and the upper mold 20 is provided with four cavities 24a and 24b, and corners of the respective cavities 24a and 24b. The movable gate pieces 25a and 25b are provided so as to be aligned with each other, and the movable gate pieces 35a and 35b are provided in the lower mold 30 corresponding to the positions of the movable gate pieces 25a and 25b provided on the upper mold 20. It has been. In this case, the movable gate pieces 25a, 25b, 35a, and 35b can be formed in a rod shape with a circular end surface.

Tapered pins 27a and 27b are provided in accordance with the positions of the movable gate pieces 25a and 25b of the upper die 20, and the movable gate pieces 25a and 25b are movable in the mold opening / closing direction by moving the taper pins 27a and 27b forward and backward. The taper pins 37a and 37b are provided in accordance with the arrangement positions of the movable gate pieces 35a and 35b of the lower die 30, and the movable gate pieces 35a and 35b are movable in the mold opening / closing direction by moving the taper pins 37a and 37b forward and backward. It is provided to become.
In the case of this embodiment as well, the movable gate pieces 25a to 35b are moved in the mold opening / closing direction by moving the taper pins 27a to 37b provided on the upper mold 20 and the lower mold 30 forward and backward, as in the above-described embodiment. It is possible to perform resin molding by appropriately adjusting the position in the mold opening / closing direction of 26.

  As described above, in the resin molding apparatus according to the present invention, the flowability of the resin in the cavity can be balanced by adjusting the position of the gate 26 in the mold opening / closing direction. Resin molding is possible. By providing the notch in the gate 26, the gate position can be adjusted while the movable gate pieces are in contact with each other, so that a highly accurate taper pin positioning mechanism is not required. Further, since the position of the gate 26 in the mold opening / closing direction can be adjusted by driving the taper pins 27a to 37b, it is not necessary to remove the resin mold from the press device each time the position of the gate 26 is adjusted. The position of the gate 26 can be easily adjusted. Further, even when the position of the gate 26 is finely adjusted depending on the product lot, it can be easily adjusted. In addition, when a new product is resin-molded, the optimum position can be easily selected even when the optimum position of the gate 26 is selected.

Further, even when a product having a different shape is targeted as a molded product, the shape of the gate 26 can be adjusted to a considerable extent by adjusting the position of the gate 26 in the mold opening / closing direction and making the opening cross-sectional area of the gate 26 adjustable. Even if the product is different, it is possible to mold the resin, and it is possible to expand the area of the resin mold target product.
In addition, although the said embodiment demonstrated the case where the single side | surface of the to-be-molded product 10 was resin-molded, the resin mold apparatus which concerns on this invention is applicable similarly when the both-sides of a to-be-molded product are resin-molded. Also in the case of a molded product in which both surfaces are resin-molded, it is possible to suppress problems such as unfilling of the resin and generation of voids by taking a balance when the resin is filled in the cavity.

It is a top view which shows the structure of the upper mold | type used by 1st Embodiment of the resin mold apparatus. It is a top view which shows the structure of the lower mold | type used in 1st Embodiment of the resin mold apparatus. It is sectional drawing which shows the structure of a resin mold metal mold | die. It is explanatory drawing which looked at the movable gate piece from the front. It is explanatory drawing which shows the state which has a gate in an up-down position. It is explanatory drawing which shows the state which has a gate in an up-down position. It is explanatory drawing which shows the state which opened the gate widely. It is explanatory drawing which shows the example of a to-be-molded product and a molded product. It is a top view which shows the structure of the upper mold | type used by 2nd Embodiment of the resin mold apparatus. It is a top view which shows the structure of the lower mold | type used by 2nd Embodiment of the resin mold apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Molded article 10a Board | substrate 10b Notch part 10c Insertion hole 11 Circuit component 12 Resin mold part 20 Upper mold | type 22 Mold cull 24a, 24b Cavity 25a, 25b, 35a, 35b Movable gate piece 26 Gate 26a Clearance 27a, 27b, 37a, 37b Taper pin 29 Contraction spring 30 Lower mold 32 Pot 34a, 34b Set part 251, 351 Tapered surface 271, 371 Tapered surface

Claims (5)

In a resin molding apparatus that clamps a molded product with an upper mold and a lower mold, fills a cavity with resin from a pot, and performs resin molding,
A movable gate piece is provided in a position adjacent to the cavity of the upper mold and the lower mold so as to be movable in the mold opening and closing direction.
A resin mold characterized in that a movable gate piece moving means is provided for defining a position in the mold opening / closing direction of the movable gate piece provided on the upper die and the lower die and a distance between the contact end surfaces of the movable gate piece. apparatus.   The movable gate piece is made of a plate-like or bar-like member, and a notch that acts as a gate is provided on the contact end surface of the movable gate piece attached to the upper mold and / or the lower mold. The resin molding apparatus according to claim 1, wherein the apparatus is a resin molding apparatus. As the moving means,
A taper pin is provided so that the tip reaches the end surface opposite to the contact end surface of the movable gate piece from the side surfaces of the upper die and the lower die, and the end surface of the movable gate piece and the tip of the taper pin are formed on the tapered surface. Provided to be able to contact each other,
3. The resin molding apparatus according to claim 1, further comprising a drive unit that moves the taper pin forward and backward to define the position of the movable gate piece in the mold opening / closing direction.   When the taper surface moves the taper pin into the mold by the driving means, the contact end surface of the movable gate piece moves in a direction approaching the opposing upper die or lower die, and the taper pin 4. The contact end surface of the movable gate piece is provided so as to move in a direction away from the opposing upper die or lower die when the die is moved out of the mold. Resin molding equipment.   5. The movable gate piece is attached to a mold by being urged so as to move in a direction in which a contact end face is separated from an opposing upper mold or lower mold. The resin molding apparatus according to one item.

Images