Resin encapsulation mold

Abstract

A resin encapsulation mold according to one embodiment is for performing resin encapsulation of a molding object so as to form an exposed surface where a section of the molding object is not covered by a resin and is exposed, said resin encapsulation mold having a cavity forming section (31) that forms a cavity in which the molding object is positioned and into which the resin flows, wherein formed in a section of the cavity forming section (31) is a recess (36) that has a contact section (362a) against which a perimeter edge section (642a) serving as the perimeter of the exposed surface is pressed, along the entire perimeter thereof, during mold clamping.

Description

Resin sealing mold

[0001] The disclosed embodiments relate to a resin-sealed mold.

[0002] A resin sealing mold for resin-sealing a molded article has been known. For example, a resin sealing mold for producing a molded article by resin-sealing a molded article so as to form an exposed surface in which a portion of the molded article is not covered with resin.

[0003] Patent Document 1 discloses a technology in which a pressure-applying member is pressed against a molded product, which is the object to be sealed, to prevent resin from entering the part of the molded product that comes into contact with the pressure-applying member, thereby exposing that part.

[0004] JP 2017-011192 A

[0005] However, in the technology described in Patent Document 1, a part of the workpiece and the pressure-applying member are in surface contact with each other, so if the workpiece is tilted, for example, a gap is formed between the workpiece and the pressure-applying member, which causes the problem of resin entering the gap between the workpiece and the pressure-applying member and generating resin burrs.

[0006] One aspect of the embodiment has been made in view of the above, and aims to provide a resin-sealing mold that can suppress the occurrence of resin burrs.

[0007] A resin sealing mold according to one aspect of the embodiment is a resin sealing mold that seals a molded product with resin so as to form an exposed surface in which a portion of the molded product is exposed and not covered by resin, and has a cavity forming portion that forms a cavity into which the molded product is placed and into which resin flows, and a recess is formed in part of the cavity forming portion that has a contact portion against which the outer peripheral edge portion, which becomes the outer periphery of the exposed surface when the mold is closed, is pressed all around.

[0008] According to one aspect of the embodiment, the occurrence of resin burrs can be suppressed.

[0009] FIG. 1 is a perspective view showing an example of the configuration of a resin sealing apparatus according to an embodiment. FIG. 2 is a side view showing an example of the configuration of a molded workpiece according to an embodiment. FIG. 3 is a bottom view showing an example of the configuration of a molded workpiece according to an embodiment. FIG. 4 is a side view showing an example of the configuration of a sleeve terminal according to an embodiment. FIG. 5 is a bottom view showing an example of the configuration of a sleeve terminal according to an embodiment. FIG. 6 is a cross-sectional view showing an example of a resin sealing apparatus according to an embodiment. FIG. 7 is an enlarged view of region VII shown in FIG. 6. FIG. 8 is a plan view showing an example of an insert according to an embodiment. FIG. 9 is a view (part 1) showing an example of a resin sealing process using a resin sealing mold according to an embodiment. FIG. 10 is an enlarged view showing an example of region X shown in FIG. 9. FIG. 11 is an enlarged view showing an example of region XI shown in FIG. 10. FIG. 12 is a plan view showing an example of a contact portion included in an inclined portion of an insert according to an embodiment. FIG. 13 is a view (part 2) showing an example of a resin sealing process using a resin sealing mold according to an embodiment. FIG. 14 is an enlarged view showing an example of region XIV shown in FIG. 13. FIG. 15 is a view (part 3) showing an example of a resin sealing process using a resin sealing mold according to an embodiment, and is an enlarged view corresponding to FIG. 14. Fig. 16 is an enlarged view showing an example of region XVI shown in Fig. 15. Fig. 17 is a side view showing an example of the configuration of a molded product according to an embodiment. Fig. 18 is a bottom view showing an example of the configuration of a molded product according to an embodiment. Fig. 19 is an enlarged view corresponding to Fig. 10 showing another example of the recess of the insert according to an embodiment. Fig. 20 is an enlarged view of region XX shown in Fig. 19. Fig. 21 is a plan view showing another example of the insert according to an embodiment. Fig. 22 is an enlarged view corresponding to Fig. 16 showing another example of the recess of the insert according to an embodiment.

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the resin-sealed mold disclosed in the present application will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments.

[0011] 1, a resin sealing apparatus 100 according to the first embodiment includes a resin sealing mold 1, a plurality of tie bars 4, a fixed platen 5, a movable platen 6, and a transfer unit 7. To facilitate understanding of the positional relationships, multiple drawings including FIG. 1 show axes of an XYZ coordinate system including an X-axis, a Y-axis, and a Z-axis that are orthogonal to one another, and the Z-axis is the up-down direction.

[0012] The tie bars 4 extend parallel to one another in the vertical direction and are supported on a base (not shown). A fixed platen 5 is fixed to the upper end of each tie bar 4, and a movable platen 6 is attached to each tie bar 4 so as to be movable in the vertical direction (Z-axis direction).

[0013] The resin sealing mold 1 includes an upper mold 2 and a lower mold 3. The upper mold 2 is attached to a fixed platen 5, and the lower mold 3 is attached to a movable platen 6. The movable platen 6 is driven by a drive mechanism (not shown) to move up and down. The upper mold 2 includes an upper chess piece 10 and an upper die set 20 that supports the upper chess piece 10. The lower mold 3 includes a lower chess piece 30 and a lower die set 40 that supports the lower chess piece 30.

[0014] In the resin sealing apparatus 100, the movable platen 6 moves upward, causing the lower mold 3 to come into contact with the upper mold 2 and clamp the upper mold 2 and the lower mold 3. In the example shown in Fig. 1, the resin sealing apparatus 100 is configured so that the lower mold 3 moves upward (positive direction of the Z axis), but it may also be configured so that the upper mold 2 moves downward (negative direction of the Z axis), or so that the lower mold 3 moves upward and the upper mold 2 moves downward.

[0015] In the resin sealing device 100, the upper mold 2 and the lower mold 3 come into contact with each other and are clamped together, thereby forming a resin supply path (e.g., a cull portion and a runner portion, etc.) and a cavity 50 (see Figure 13) in the space between the upper mold 2 and the lower mold 3, and the molded product 60 is resin-sealed within the cavity 50 (see Figure 13).

[0016] 1 is configured to resin-seal six molded articles 60, but is not limited to this example, and the number of molded articles 60 that can be resin-sealed simultaneously may be five or less, or seven or more. Also, in the resin sealing apparatus 100 shown in FIG. 1, six pots 8 in which resin tablets are respectively placed are used to resin-seal six molded articles 60, but is not limited to this example, and the number of pots 8 may be five or less, or seven or more.

[0017] 2 and 3, the molded product 60 includes a lead frame 61 and a plurality of sleeve terminals 62. Each sleeve terminal 62 is formed in a cylindrical shape and is inserted into a corresponding one of a plurality of insertion holes 611 formed in the lead frame 61.

[0018] For example, a press-fit terminal (not shown) or the like is inserted into each sleeve terminal 62 after the resin molding of the molded product 60 by the resin sealing apparatus 100. Each sleeve terminal 62 is, for example, a metal terminal and is also called a pin holder. The molded product 60 includes, for example, an electrical component such as a semiconductor element (not shown), but is not limited to this example.

[0019] 4 and 5, each sleeve terminal 62 has a main body 63 with a hollow 631 inside, and an annular flange 64 having an outer diameter larger than that of the main body 63. The press-fit terminal (not shown) described above or the like is inserted into the hollow 631 of the main body 63 through an opening 641 in the flange 64.

[0020] The resin sealing mold 1 of the resin sealing device 100 seals the molded product 60 with resin so as to form an exposed surface in which a portion of the molded product 60 is exposed and not covered by resin, thereby producing the molded product 70 (see Figures 17 and 18) described below.

[0021] 3, a surface 642 of the flange 64 of each sleeve terminal 62 is formed as an exposed surface during resin sealing using the resin sealing mold 1. The surface 642 of the annular flange 64 is a flat surface, but is not limited to this example.

[0022] The configuration of the resin sealing mold 1 of the resin sealing apparatus 100 and the resin sealing process of resin sealing the molded product 60 using the resin sealing mold 1 of the resin sealing apparatus 100 will be described in detail below.

[0023] 6, in the resin sealing mold 1 of the resin sealing apparatus 100, an upper mold 2 including an upper chess piece 10 and a lower mold 3 including a lower chess piece 30 are positioned apart from each other in the mold clamping direction (Z-axis direction). In the resin sealing process for the molded product 60, the lower mold 3 is moved in a direction toward the upper mold 2 (positive direction of the Z-axis) and comes into contact with the upper mold 2 in a mold clamping state.

[0024] The upper die chess 10 of the upper die 2 includes a cavity forming portion 11 that forms part of the cavity 50 (see FIG. 13), a runner forming portion (not shown) that forms part of the runner portion (not shown), and a part of the cull forming portion (not shown) that forms the cull portion (not shown). Each of the cavity 50 (see FIG. 13), the cull portion (not shown), and the runner portion (not shown) is a space that is formed when the upper die 2 and the lower die 3 are clamped together.

[0025] The lower die chess 30 of the lower die 3 includes a cavity forming portion 31 that forms part of the cavity 50 (see Figure 13), a runner forming portion (not shown) that forms a runner portion (not shown), and a cull forming portion (not shown) that forms a cull portion (not shown).

[0026] The lower chess set 30 includes a plurality of lower chess body parts 32, a plurality of nesting members 33 each movable relative to a corresponding one of the plurality of lower chess body parts 32, and a plurality of support members 34 each supporting a corresponding one of the plurality of nesting members 33.

[0027] The support member 34 is, for example, an elastic member such as a spring, but may be, for example, a hydraulic member, etc., as long as it can hold the insert 33 so that the insert 33 can be moved in the direction opposite to the mold clamping direction (negative direction of the Z axis) during mold clamping. The mold clamping direction is the direction in which the upper mold 2 and the lower mold 3 approach each other.

[0028] 7, the lower chess piece body 32 includes a cavity forming portion 32a that forms part of the cavity forming portion 31, and a plurality of insertion holes 32b through which corresponding ones of the plurality of inserts 33 are inserted. The lower chess piece body 32 also includes the above-mentioned runner forming portion and cull forming portion (not shown).

[0029] Each of the inserts 33 is inserted into a corresponding one of the multiple insertion holes 32b in the lower chess piece body 32. The upper surface 35 of the insert 33 shown in Figure 7 forms part of the cavity forming portion 31, and has a recess 36 and a flat portion 37 surrounding the recess 36.

[0030] 7, the recess 36 has an annular inclined portion 362 that surrounds a central portion 361 of the recess 36 and is inclined toward the central portion 361 of the recess 36. The inclined portion 362 of the recess 36 is formed in an arc-like slope.

[0031] The inclined portion 362 shown in Fig. 7 has a shape that is rotationally symmetrical about the central portion 361 and is formed into a shape having a spherical curved surface, but the shape is not limited to that shown in Fig. 7 as long as the inclination is formed in an arc shape. For example, the arc-shaped inclination may be an inclination in which the inclination angle gradually decreases toward the central portion 361, or an inclination in which the inclination angle gradually increases toward the central portion 361.

[0032] 7, a conveying device (not shown) places each molded article 60 between the upper mold 2 and the lower mold 3. In the example shown in Fig. 9, each molded article 60 is placed between the upper mold 2 and the lower mold 3, on the lower mold chest 30 of the lower mold 3.

[0033] When the upper mold 2 and the lower mold 3 are clamped together, each of the flanges 64 of the multiple sleeve terminals 62 in each molded product 60 is positioned on the recess 36 formed on the upper surface 35 of the corresponding one of the multiple nests 33, as shown in Figure 10.

[0034] 10 and 11 , the inclined portion 362 of the recess 36 has an abutting portion 362a against which the outer peripheral edge 642a of the surface 642 of the flange 64 of the sleeve terminal 62 is pressed. The outer peripheral edge 642a has an annular shape, and the inclined portion 362 of the recess 36 has a larger outer diameter than the outer peripheral edge 642a, and as described above, the inclined portion 362 of the recess 36 is formed with an arc-shaped slope. Since the abutting portion 362a is part of the inclined portion 362, it has an arc-shaped slope.

[0035] Therefore, even if a positional shift occurs along the XY plane when the upper chess piece 10 and the lower chess piece 30 are clamped, as shown in Figure 12, the inclined portion 362 of the recess 36 can ensure that the outer peripheral edge 642a is pressed against the entire circumference as the abutment portion 362a.

[0036] Thereafter, the movable platen 6 (see FIG. 1) moves upward (positive direction of the Z axis), causing the lower mold 3 to move upward (positive direction of the Z axis) toward the upper mold 2. When the lower mold 3 moves upward (positive direction of the Z axis), the upper mold 2 and the lower mold 3 are clamped together, as shown in FIG. 13, and the molded product 60 is sandwiched between the upper mold chess 10 of the upper mold 2 and the lower mold chess 30 of the lower mold 3.

[0037] When the upper mold 2 and the lower mold 3 are clamped together, the outer peripheral edge 642a of the surface 642 of the flange 64 of the sleeve terminal 62 is pressed against the inclined portion 362 of the recess 36 of the insert 33, and a portion of the outer peripheral edge 642a is crushed and deformed. Therefore, even if there is variation in the flatness or surface density of the surface 642 of the flange 64, the outer peripheral edge 642a will be in close contact with the inclined portion 362 of the recess 36 of the insert 33 over the entire circumference.

[0038] Furthermore, a cavity 50 is formed by clamping the upper mold 2 and the lower mold 3 together, and a molded product 60 is placed in the cavity 50. After that, the resin tablet placed in the pot 8 (see FIG. 1) melts, and as shown in FIG. 15, the molten resin 9 fills the cavity 50 through the cull portion and runner portion (not shown).

[0039] At this time, as described above, the outer peripheral edge 642a of the surface 642 of the flange 64 of the sleeve terminal 62 is in close contact with the inclined portion 362 of the recess 36 of the insert 33, and therefore, as shown in Figure 16, the intrusion of resin 9 from the outer peripheral edge 642a of the surface 642 of the flange 64 to the inner portion thereof is suppressed.

[0040] Therefore, an exposed surface is formed on the surface 642 of the flange 64 of the sleeve terminal 62 from the outer peripheral edge 642a to the inner portion thereof, and the occurrence of resin burrs on the surface 642 of the flange 64 of the sleeve terminal 62 is suppressed.

[0041] Thereafter, in the resin sealing apparatus 100, the movable platen 6 (see FIG. 1) moves downward (in the negative Z-axis direction), thereby moving the lower mold 3 downward (in the negative Z-axis direction). This releases the clamping between the upper mold 2 and the lower mold 3. Then, the molded product 70 (see FIGS. 17 and 18) is removed from the resin sealing mold 1 by a conveying device (not shown).

[0042] 17 and 18 , in molded product 70, lead frame 61 and a portion of each of multiple sleeve terminals 62 are resin-sealed, and lead frame 61 and a portion of each of multiple sleeve terminals 62 are covered with molded resin 71. Molded resin 71 is formed by filling cavity 50 with molten resin 9 as described above.

[0043] The molded resin 71 is formed with a plurality of insertion holes 711, each of which reaches the flange 64 of a corresponding one of the plurality of sleeve terminals 62. After the molded product 70 is incorporated into a device (not shown), a press-fit terminal (not shown) is inserted into the insertion holes 711. The press-fit terminal (not shown) inserted into the insertion holes 711 is then inserted into the insertion hole 611 via the opening 641 in the sleeve terminal 62.

[0044] In the recess 36 of the above-described insert 33, the annular inclined portion 362 is inclined in an arc, and therefore the abutting portion 362a has an arc-shaped inclination. However, the annular inclined portion 362 is not limited to this, and as shown in Figures 19 to 21, the inclination may be formed linearly, and the abutting portion 362a may also be inclined linearly.

[0045] The linear inclination has a constant inclination angle, but is not limited to an inclination having a strictly constant inclination angle, and may have any inclination that allows the outer peripheral edge portion 642a to be in close contact along the entire circumference. The recess 36 shown in Figures 19 to 21 is a truncated cone-shaped recess, and the inclined portion 362 has a shape that is rotationally symmetrical about the central portion 361.

[0046] 19 to 21 forms part of the cavity-forming portion 31, and has a recess 36 and a flat portion 37 surrounding the recess 36. As shown in Fig. 20, the recess 36 has a flat portion 363 including a central portion 361 of the recess 36, and an annular inclined portion 362 surrounding the flat portion 363 and inclined toward the central portion 361 of the recess 36. The inclined portion 362 of the recess 36 is formed so as to have a linear slope.

[0047] When the upper mold 2 and the lower mold 3 are clamped together, the outer peripheral edge 642a of the surface 642 of the flange 64 of the sleeve terminal 62 is pressed against the inclined portion 362 of the recess 36 of the insert 33, and a portion of the outer peripheral edge 642a is crushed and deformed. Therefore, even if there is variation in the flatness or surface density of the surface 642 of the flange 64, the outer peripheral edge 642a will be in close contact with the inclined portion 362 of the recess 36 of the insert 33 over the entire circumference.

[0048] Therefore, even if a positional shift occurs along the XY plane when the upper chess piece 10 and the lower chess piece 30 are clamped, as shown in Figure 21, the inclined portion 362 of the recess 36 can ensure that the outer peripheral edge 642a is pressed against the entire circumference as the abutment portion 362a.

[0049] 19 and 20, molten resin 9 is filled into cavity 50 via the cull portion and runner portion (not shown). In this case, as described above, outer peripheral edge portion 642a of surface 642 of flange 64 of sleeve terminal 62 is in close contact with inclined portion 362 of recess 36 of insert 33, and therefore, as shown in FIG. 22, intrusion of resin 9 from outer peripheral edge portion 642a of surface 642 of flange 64 to the portion inward thereof is suppressed.

[0050] Therefore, an exposed surface is formed on the surface 642 of the flange 64 of the sleeve terminal 62 from the outer peripheral edge 642a to the inner portion thereof, and the occurrence of resin burrs on the surface 642 of the flange 64 of the sleeve terminal 62 is suppressed.

[0051] In the above example, the support member 34 is, for example, an elastic member such as a spring or a hydraulic member, but is not limited to such an example as long as it can support the insert 33. Also, the lower chess piece 30 is configured to have the lower chess piece main body 32 and the insert 33, but the lower chess piece main body 32 and the insert 33 may be formed integrally.

[0052] In the example described above, the outer peripheral edge portion 642a is formed in an annular shape, and the inclined portion 362 has a shape that is rotationally symmetrical about the central portion 361, but as long as the outer peripheral edge portion 642a is configured to be pressed against the abutment portion 362a along the entire circumference, the shapes of the outer peripheral edge portion 642a and the inclined portion 362 are not limited to the example described above. For example, when the outer peripheral edge portion 642a is formed in a polygonal shape (e.g., a regular polygon), the inclined portion 362 may have the shape of the inclined portion of the recess of a truncated polygonal pyramid (e.g., a truncated regular polygonal pyramid).

[0053] As described above, the resin sealing mold 1 according to the embodiment is a resin sealing mold that seals the molded product 60 with resin so as to form an exposed surface where a portion of the molded product 60 is exposed and not covered with resin, and has a cavity forming portion 31 that forms the cavity 50 where the molded product 60 is placed and into which the resin flows, and a recess 36 having a contact portion 362a that is pressed over the entire circumference of the outer periphery 642a that forms the outer periphery of the exposed surface when the mold is closed is formed in a part of the cavity forming portion 31. This makes it possible for the resin sealing mold 1 to suppress the occurrence of resin burrs in the exposed surface portion of the molded product 60.

[0054] The recess 36 also has an annular inclined portion 362 that surrounds the center of the recess 36 and is inclined toward the center of the recess 36, and the abutment portion 362a is formed on the annular inclined portion 362. As a result, even if a positional deviation occurs along the XY plane when the upper and lower chess pieces 10 and 30 are clamped together, the resin-sealing mold 1 can ensure that the area against which the outer peripheral edge 642a is pressed over the entire circumference serves as the abutment portion 362a.

[0055] The inclined portion 362 is formed to have an arc-shaped inclination, which allows the resin sealing mold 1 to suppress the occurrence of resin burrs on the exposed surface of the molded product 60.

[0056] Furthermore, the inclined portion 362 is formed so that the inclination is linear. This allows the resin sealing mold 1 to suppress the occurrence of resin burrs on the exposed surface of the molded product 60.

[0057] The resin sealing mold 1 also has a nest 33 that forms part of the cavity forming portion 31 including the recess 36 and that is movable in the direction opposite to the mold clamping direction when the mold is clamped. This makes it possible to prevent excessive force from being applied to the exposed surface of the molded product 60 when the mold is clamped.

[0058] Further advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

[0059] REFERENCE SIGNS LIST 1 Resin sealing mold 2 Upper mold 3 Lower mold 4 Tie bar 5 Fixed platen 6 Movable platen 7 Transfer unit 8 Pot 9 Resin 10 Upper die chess 11, 31, 32a Cavity forming portion 20 Upper die set 30 Lower die chess 32 Lower die chess main body portion 32b, 611 Insertion hole 34 Support member 35 Upper surface 36 Recessed portion 37, 363 Flat portion 40 Lower die set 50 Cavity 60 Molded product 61 Lead frame 62 Sleeve terminal 63 Main body portion 64 Flange 70 Molded product 71 Molded resin 100 Resin sealing device 361 Center portion 362 Inclined portion 362a Contact portion 631 Cavity 641 Opening 642 Surface 642a Outer periphery 711 Insertion hole

Claims

1. A resin sealing mold for resin-sealing a molded product so as to form an exposed surface where a portion of the molded product is exposed and not covered by resin, the resin sealing mold having a cavity-forming portion in which the molded product is placed and into which the resin flows, and a recess having a contact portion against which the outer periphery of the exposed surface is pressed all around when the mold is closed is formed in a portion of the cavity-forming portion.

2. The resin sealing mold according to claim 1, characterized in that the recess has an annular inclined portion surrounding the center of the recess and inclining toward the center of the recess, and the abutment portion is formed on the annular inclined portion.

3. The resin sealing mold according to claim 2, characterized in that the inclined portion is formed in an arc shape.

4. The resin sealing mold according to claim 2, characterized in that the inclined portion is formed so that the inclination is linear.

5. A resin sealing mold according to claim 1 or 2, characterized in that it has a nest that forms part of the cavity forming portion including the recess and is movable in the opposite direction to the mold clamping direction during the mold clamping.

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