Resin molding device and method for manufacturing molded resin article

Abstract

The present invention provides a resin molding device capable of reducing a time difference for the completion of filling with a resin material supplied from one pot to a plurality of cavities.　A mold is formed by: a runner part, which is formed by an upper surface of an intermediate die and a lower surface of an upper die, and which guides the resin material supplied from the pot; a gate part, which is formed in the intermediate die, and which guides the resin material from the runner part to the lower surface of the intermediate die; a first cavity, which is formed by an upper surface of a lower die and a lower surface of the intermediate die, is in communication with the gate part, and is formed in a long shape extending from the gate part in an approaching direction going toward a pot block; and a second cavity, which is formed by the upper surface of the lower die and the lower surface of the intermediate die, is in communication with the gate part, and is formed in a long shape extending from the gate part in a distancing direction going away from the pot block.

Description

Resin molding apparatus and method for manufacturing a resin molded product

[0001] The present invention relates to the technology of a resin molding apparatus and a method for manufacturing a resin molded product.

[0002] Patent Document 1 discloses a resin molding apparatus that resin-molds a lead frame by a transfer method. In the technology described in Patent Document 1, a lead frame is sandwiched between an upper mold and a lower mold, and mold clamping is performed. In addition, a plurality of long cavities are formed in the upper mold and the lower mold. A gate is formed at one end of the cavity. The pot for accommodating the resin material communicates with the gates of the plurality of cavities. The molten resin material is supplied from the pot to the plurality of cavities through the gates.

[0003] Japanese Patent Application Laid-Open No. 5-200769

[0004] Here, since the resin material generally contains a filler, the speed at which the molten resin material flows through the gate changes over time. Therefore, in a resin molding apparatus in which one pot communicates with a plurality of cavities as described in Patent Document 1, it is difficult to simultaneously complete the filling of the resin material into the plurality of cavities.

[0005] If the filling of the resin material into one cavity is completed, the flow rate of the resin material increases in other cavities where the filling of the resin material has not been completed. When the resin material with an increased speed flows on the lead frame, the bonding wire formed on the lead frame is likely to be deformed.

[0006] The present invention has been made in view of the above circumstances, and the problem to be solved is to provide a resin molding apparatus and a method for manufacturing a resin molded product that can reduce the time difference in the completion of the filling of the resin material supplied from one pot to a plurality of cavities.

[0007] The problems that the present invention aims to solve are as described above, and in order to solve these problems, the present invention provides a resin molding apparatus comprising: an upper mold; a lower mold having a pot block on which a pot for containing resin material is formed and positioned below the upper mold; an intermediate mold positioned between the upper mold and the lower mold; and a clamping mechanism for clamping the molding apparatus, wherein the molding apparatus comprises: a runner portion formed by the upper surface of the intermediate mold and the lower surface of the upper mold for guiding the resin material supplied from the pot; and a front The mold includes a gate portion that guides the resin material from the runner portion to the lower surface of the intermediate mold, a first cavity formed by the upper surface of the lower mold and the lower surface of the intermediate mold, connected to the gate portion, and formed in an elongated shape extending from the gate portion in a proximity direction toward the pot block, and a second cavity formed by the upper surface of the lower mold and the lower surface of the intermediate mold, connected to the gate portion, and formed in an elongated shape extending from the gate portion in a distance direction toward the pot block.

[0008] Furthermore, the method for manufacturing a resin molded product according to the present invention is a method for manufacturing a resin molded product using a resin molding apparatus, and includes clamping the mold to perform resin molding and opening the mold to unload the resin molded product.

[0009] According to the present invention, the time difference in the completion of filling of resin material supplied from one pot to multiple cavities can be reduced.

[0010] A schematic plan view showing the overall configuration of the resin molding apparatus according to the first embodiment. A front cross-sectional view showing the molding mechanism according to the first embodiment. A partially enlarged view of Figure 2. A schematic plan view showing the lower mold, runner section, and cavity. A schematic plan view showing how resin material is filled into multiple cavities. A partially enlarged front cross-sectional view of the molding mechanism according to the second embodiment. A schematic plan view showing the lower mold, runner section, and cavity according to the second embodiment. A schematic plan view showing the lower mold, runner section, and cavity according to the third embodiment. A schematic plan view showing the lower mold, runner section, and cavity according to the fourth embodiment. A schematic plan view showing the lower mold and exhaust passage, runner section, and cavity according to the fifth embodiment.

[0011] In the following explanation, the directions indicated by arrows U, D, L, R, F, and B in the diagram will be defined as the upward, downward, left, right, forward, and backward directions, respectively.

[0012] <Overall Configuration of Resin Molding Apparatus 1> First, the configuration of the resin molding apparatus 1 according to the first embodiment will be described using Figure 1. The resin molding apparatus 1 is used to encapsulate electronic elements such as semiconductor chips in resin and to manufacture resin molded products. In particular, this embodiment illustrates a resin molding apparatus 1 that performs resin molding (transfer molding) using the transfer molding method.

[0013] The resin molding apparatus 1 comprises a supply module 10, a resin molding module 20, and a discharge module 30 as its components. Each component is detachable and interchangeable with respect to the other components.

[0014] <Supply Module 10> The supply module 10 supplies a lead frame 2, which is a type of substrate, and a resin tablet T to the resin molding module 20. Electronic elements are fixed to the lead frame 2 supplied by the supply module 10. The lead frame 2 is resin-molded by resin sealing the electronic elements. In this embodiment, the lead frame 2 is shown as an example of a substrate, but various other substrates (glass epoxy substrates, ceramic substrates, resin substrates, metal substrates, etc.) can also be used. The supply module 10 mainly comprises a frame delivery unit 11, a frame supply unit 13, a resin material supply mechanism 14, and a control unit 18.

[0015] The frame delivery unit 11 sends the lead frames 2, which are housed in an in-magazine unit (not shown) and are not yet molded by resin, to the frame supply unit 13. The frame supply unit 13 receives the lead frames 2 from the frame delivery unit 11, aligns the received lead frames 2 appropriately, and hands them over to the loader 17, which will be described later.

[0016] The resin material supply mechanism 14 supplies resin tablets T to the loader 17. The resin material supply mechanism 14 can align multiple resin tablets T and hand them over to the loader 17.

[0017] The control unit 18 controls the operation of each module of the resin molding apparatus 1. The control unit 18 controls the operation of the supply module 10, the resin molding module 20, and the discharge module 30. Furthermore, the operation of each module can be arbitrarily changed (adjusted) using the control unit 18.

[0018] In this embodiment, an example is shown in which the control unit 18 is provided on the supply module 10, but it is also possible to provide the control unit 18 on other modules. Furthermore, it is possible to provide multiple control units 18. For example, it is possible to provide a control unit 18 for each module or device and individually control the operation of each module, etc., while coordinating their operation with each other.

[0019] <Resin Molding Module 20> The resin molding module 20 resin-moldes the lead frame 2 by resin-encapsulating electronic elements fixed to the lead frame 2. In this embodiment, two resin molding modules 20 are arranged side by side. Note that there may be one resin molding module 20 or three or more. By performing resin molding of the lead frame 2 in parallel using multiple resin molding modules 20, the manufacturing efficiency of the resin molded product can be improved. The resin molding module 20 mainly comprises a molding mechanism 100.

[0020] The molding mechanism 100 mainly comprises a molding die and a mold clamping mechanism 160.

[0021] The mold uses molten resin material to resin-encapsulate the electronic elements fixed to the lead frame 2. The mold comprises multiple molds arranged vertically, namely an upper mold 110, a lower mold 120, and an intermediate mold 130 (see Figure 2, etc.).

[0022] The mold clamping mechanism 160 clamps and opens the molding die by moving the lower die 120 up and down. The specific configuration of the molding mechanism 100 will be described later.

[0023] <Unloading Module 30> The unloading module 30 receives the resin-molded lead frame 2 from the resin molding module 20 and unloads it. The unloading module 30 mainly comprises a substrate housing section 32. The substrate housing section 32 houses the resin-molded lead frame 2.

[0024] <Loader 17> A loader 17 is provided in the supply module 10 and the resin molding module 20. The loader 17 transports the lead frame 2 and resin tablet T received from the frame supply unit 13 and the resin material supply mechanism 14 to the resin molding module 20. The loader 17 can move within the supply module 10 and the resin molding module 20 along rails (not shown).

[0025] <Unloader 31> An unloader 31 is provided in the resin molding module 20 and the unloading module 30. The unloader 31 holds the resin-molded lead frame 2 and unloads it to the substrate housing section 32. The unloader 31 can move within the resin molding module 20 and the unloading module 30 along rails (not shown).

[0026] <Method for Manufacturing Resin Molded Products> The following describes a method for manufacturing resin molded products using the resin molding apparatus 1 configured as described above. The control unit 18 can manufacture resin molded products by controlling the operation of each unit of the resin molding apparatus 1.

[0027] First, the frame delivery unit 11 of the supply module 10 sends two lead frames 2, which are not yet molded by resin, to the frame supply unit 13. The frame supply unit 13 aligns the two lead frames 2 that it received from the frame delivery unit 11.

[0028] Next, the loader 17 holds the two lead frames 2 of the frame supply unit 13 and the multiple resin tablets T of the resin material supply mechanism 14. The loader 17 transports the held lead frames 2 and resin tablets T to the lower mold 120 of the resin molding module 20. The loader 17 places the lead frames 2 on the lower mold 120 and places the resin tablets T into the pot 122a (see Figure 2) of the lower mold 120. The resin tablets T are thermosetting resins. When the resin tablets T are heated, their temperature rises. As a result, the resin tablets T become molten resin material and then harden. The upper mold 110 and the lower mold 120 are heated to a predetermined temperature, for example, 175 degrees. Therefore, when the resin tablets T are placed in the pot 122a, they are heated by the lower mold 120 and become molten resin material.

[0029] Next, the lower mold 120 is raised by the clamping mechanism 160, and the mold is clamped. In this state, the plunger 124, which will be described later, injects the molten resin material present in the pot 122a. As a result, the molten resin material fills the cavity of the mold. The filled resin material is continuously heated. After a certain period of time (curing time) has elapsed since the filling is completed, the resin material hardens, and the electronic elements fixed to the lead frame 2 are resin-encapsulated, and a resin molded product (resin-molded lead frame 2) can be obtained.

[0030] Next, the lower mold 120 is lowered by the mold clamping mechanism 160, and the mold is opened. After that, the resin-molded lead frame 2 is unloaded from the resin molding module 20 by the unloader 31.

[0031] Next, the resin-molded lead frame 2 is transferred to the unloading module 30 by the unloader 31. The unloader 31 then places the resin-molded lead frame 2 into the substrate housing section 32.

[0032] <Configuration of the molding mechanism 100> Next, the configuration of the molding mechanism 100 will be explained in more detail using Figures 1 to 4.

[0033] The molding mechanism 100 shown in Figure 2 mainly comprises an upper mold 110, a lower mold 120, an intermediate mold 130, a fixed platen 140, a movable platen 150, a mold clamping mechanism 160, and the like.

[0034] The upper mold 110 forms the upper part of the mold. The upper mold 110 is fixed to the lower surface of the fixed platen 140, which is fixed to tie bars (not shown). This supports the upper mold 110 in an immovable state. In this case, tie bars are arranged at the four corners of the mold. Note that the members that fix the fixed platen 140 are not limited to tie bars (not shown), but may be plate-shaped hold frames. In this case, in Figure 1, one hold frame is arranged on the left side of the lower mold 120, and another hold frame is arranged on the right side of the lower mold 120. The upper mold 110 mainly comprises an upper mold block 111, retaining pins (not shown), etc.

[0035] The upper mold block 111 forms a guide section and a runner section between itself and the intermediate mold 130 for guiding the resin material. The guide section and the runner section are passages through which the molten resin material flows. The upper mold block 111 is formed in a substantially rectangular parallelepiped shape. A projection 111a is formed on the lower surface of the upper mold block 111.

[0036] The protruding portion 111a is a part that protrudes downward from the lower surface of the upper mold block 111. The protruding portion 111a is formed in a position that faces the pot 122a of the lower mold 120 in the vertical direction.

[0037] The lower mold 120 shown in Figure 2 forms the lower part of the molding die. The lower mold 120 is fixed to the upper surface of the movable platen 150. This allows the lower mold 120 to move up and down in conjunction with the vertical movement of the movable platen 150. The lower mold 120 mainly comprises a lower mold block 121, a pot block 122, a lower block 123, a plunger 124, an ejector pin 125, an ejector plate 126, a movable shaft 127, a spring 128, and an ejector rod 129, etc.

[0038] The lower mold block 121 forms a cavity between itself and the intermediate mold 130. The lower mold block 121 is formed in a roughly rectangular parallelepiped shape. Two lower mold blocks 121 are provided side by side, flanking the pot block 122. As shown in Figures 3 and 4, the upper surface of the lower mold block 121 has a resin reservoir 171, a constricted portion 172, a first cavity portion 173, a second cavity portion 174, a first air vent 175, and a second air vent 176 (hereinafter collectively referred to as "resin reservoir 171, etc.").

[0039] As shown in Figure 2, the lower mold block 121 is formed symmetrically on both sides of the pot block 122. Therefore, in the following explanation, we will mainly focus on the right-side lower mold block 121, as shown in Figures 3 and 4.

[0040] Furthermore, since the drawings schematically show the configuration (shape, dimensions, etc.) of the resin molding apparatus 1, the dimensions of the configuration shown in each figure do not necessarily match. For example, Figure 4 shows the first cavity section 173 and the second cavity section 174, which are elongated in the left-right direction, but in Figure 3, for convenience, the left-right lengths of the first cavity section 173 and the second cavity section 174 are shown to be relatively shorter.

[0041] The resin reservoir 171 shown in Figures 3 and 4 is for guiding the resin material supplied via the gate 188 (described later) to the first cavity 173 and the second cavity 174 after it has been allowed to accumulate. The resin reservoir 171 is formed by recessing the upper surface of the lower mold block 121 downwards. The resin reservoir 171 is formed to be located directly below the gate 188. Although Figure 4 shows the resin reservoir 171 formed in a rectangular shape in plan view, the shape of the resin reservoir 171 is not particularly limited.

[0042] The throttle portion 172 is for supplying the resin material from the resin reservoir portion 171 to the first cavity portion 173 and the second cavity portion 174. The throttle portion 172 is formed so as to recess the upper surface of the lower mold block 121 downward. The throttle portion 172 is formed so as to be connected to both the left and right sides of the resin reservoir portion 171 respectively. The throttle portion 172 is formed shallower than the resin reservoir portion 171. Also, the width of the throttle portion 172 in the front-rear direction is formed to be equal to or less than the width of the resin reservoir portion 171 in the front-rear direction.

[0043] The first cavity portion 173 is for curing the resin material into a shape corresponding to the resin molded product. The first cavity portion 173 is formed so as to recess the upper surface of the lower mold block 121 downward. The first cavity portion 173 is formed in a shape corresponding to the portion of the resin molded product that is resin-sealed. In the present embodiment, the first cavity portion 173 is formed in a rectangular shape in plan view. The first cavity portion 173 is formed in a long shape that is long in the left-right direction. The first cavity portion 173 is formed on the left side of the resin reservoir portion 171. The right end portion of the first cavity portion 173 is communicated with the resin reservoir portion 171 via the throttle portion 172. The first cavity portion 173 is formed so as to extend from the resin reservoir portion 171 side in the proximity direction approaching the pot block 122 described later. The first cavity portion 173 is formed so as to extend perpendicularly to the side surface (right side surface) of the pot block 122 in plan view.

[0044] As shown in FIG. 4, the first cavity portion 173 is formed in a long rectangular shape in which the length (long side) in the left-right direction is longer than the width (short side) in the front-rear direction in plan view. In the present embodiment, the length A of the long side of the first cavity portion 173 is formed to be three times or more (A≧3×B) the length B of the short side of the first cavity portion 173. Also, in the present embodiment, the length A of the long side of the first cavity portion 173 is formed to be one-third or more (A≧C×1 / 3) the width C of the lead frame 2 placed on the lower mold block 121 in the left-right direction (short side direction).

[0045] The second cavity portion 174 is for curing the resin material into a shape corresponding to the resin molded product. The second cavity portion 174 is formed so as to recess the upper surface of the lower mold block 121 downwards. The second cavity portion 174 is formed into a shape corresponding to the resin-sealed portion of the resin molded product. In this embodiment, the second cavity portion 174 is formed in a shape symmetrical to the first cavity portion 173, with the resin reservoir portion 171 in between. The length of the second cavity portion 174 in the left-right direction (longitudinal direction) is formed to be the same as the length of the first cavity portion 173 in the left-right direction. However, the lengths of the first cavity portion 173 and the second cavity portion 174 may differ within the range of manufacturing tolerances. Here, "same" does not only mean that the two lengths match, but also includes the state in which the two lengths differ within the range of manufacturing tolerances. The left end of the second cavity 174 is connected to the resin reservoir 171 via the constricted portion 172. The second cavity 174 is formed to extend from the resin reservoir 171 side toward the remote direction away from the pot block 122, which will be described later. In the lower mold block 121 located to the right of the pot block 122, the proximity direction is to the left and the remote direction is to the right. In the lower mold block 121 located to the left of the pot block 122, the proximity direction is to the right and the remote direction is to the left.

[0046] In this embodiment, the first cavity portion 173 and the second cavity portion 174 are shown extending in the left-right direction (perpendicular to the right side of the pot block 122), but the present invention is not limited to this. For example, the first cavity portion 173 does not necessarily have to be perpendicular to the right side of the pot block 122, as long as it extends from the gate portion 188 toward the pot block 122 side (left side). The same applies to the second cavity portion 174.

[0047] The first air vent 175 is for discharging air and gas generated from the resin material within the first cavity portion 173. The first air vent 175 is formed by recessing the upper surface of the lower die block 121 downward. In the right lower die block 121, the first air vent 175 is formed so as to connect to the left end portion of the first cavity portion 173. The first air vent 175 is formed so as to extend from the first cavity portion 173 to the left end portion of the right lower die block 121. The first air vent 175 is formed shallower than the first cavity portion 173.

[0048] The second air vent 176 is for discharging air and gas generated from the resin material within the second cavity portion 174. The second air vent 176 is formed by recessing the upper surface of the lower die block 121 downward. In the right lower die block 121, the second air vent 176 is formed so as to connect to the right end portion of the second cavity portion 174. The second air vent 176 is formed so as to extend from the second cavity portion 174 to the right end portion of the right lower die block 121. The second air vent 176 is formed shallower than the second cavity portion 174. As described above, the first air vent 175 is formed at the end portion in the proximity direction in the first cavity portion 173, and the second air vent 176 is formed at the end portion in the remote direction in the second cavity portion 174.

[0049] In this way, as shown in FIG. 4, in the lower die block 121, the first cavity portion 173 and the second cavity portion 174 that linearly extend left and right with the resin reservoir portion 171 interposed therebetween are formed. By the first cavity portion 173 and the second cavity portion 174, resin molding can be performed in a long range along the short direction (left - right direction) of the lead frame 2.

[0050] Also, as shown in FIG. 4, a plurality of resin reservoir portions 171, throttle portions 172, first cavity portions 173, second cavity portions 174, first air vents 175, and second air vents 176 that communicate with each other are formed side - by - side in the front - rear direction on the upper surface of the lower die block 121.

[0051] The pot block 122 shown in Figure 2 is the part that can accommodate the resin tablet T. The pot block 122 is formed in a substantially rectangular parallelepiped shape. The pot block 122 is positioned between the left and right lower mold blocks 121. A pot 122a is formed in the pot block 122 so as to penetrate the pot block 122 vertically. The diameter of the pot 122a is formed to a size that can accommodate a substantially cylindrical resin tablet T.

[0052] The lower block 123 holds the lower mold block 121 and the pot block 122. The lower parts of the lower mold block 121 and the pot block 122 are fixed to the upper part of the lower block 123. The lower block 123 has a first housing section 123a and a second housing section 123b formed therein.

[0053] The first housing section 123a is a part that houses the ejector plate 126 and the like. The first housing section 123a is formed below the lower mold block 121 and the pot block 122.

[0054] The second housing section 123b is a section for housing the spring 128 and the like. The second housing section 123b is formed below the first housing section 123a. The second housing sections 123b are formed near both the left and right ends of the lower block 123.

[0055] The plunger 124 injects the resin tablet T contained in the pot 122a and supplies it to the aforementioned cavity. The plunger 124 is positioned to be movable up and down within the pot 122a. The plunger 124 can move up and down by the driving force of the plunger drive unit 124a provided at its lower part. The plunger drive unit 124a can be formed by, for example, a servo motor or an air cylinder.

[0056] The ejector pin 125 is used to release the resin-molded lead frame 2 from the lower mold 120. The ejector pin 125 is formed in a substantially cylindrical shape. The ejector pin 125 is positioned with its longitudinal direction facing up and down. The ejector pin 125 penetrates the lower mold block 121 vertically and is positioned to be movable vertically relative to the lower mold block 121. The upper end of the ejector pin 125 is positioned to be exposed to the first cavity portion 173 or the second cavity portion 174.

[0057] The ejector plate 126 connects a plurality of ejector pins 125. The ejector plate 126 is formed in a flat plate shape. The ejector plate 126 is housed in the first housing portion 123a of the lower block 123. The ejector plate 126 connects the lower parts of the plurality of ejector pins 125 provided on the lower mold block 121. The ejector plate 126 is provided so as to span the left and right lower mold blocks 121. In Figure 2, for convenience, the ejector plate 126 is shown as being separated into left and right halves, but in reality, the ejector plate 126 is formed as a single unit. In the ejector plate 126, openings are provided in the portion through which the plunger 124 and the plunger drive unit 124a pass. The ejector plate 126 is supported by appropriate guide members (not shown) so as to be able to move up and down.

[0058] The movable shaft 127 is used to raise and lower the ejector plate 126. The movable shaft 127 penetrates vertically through the lower part of the lower block 123 (the partition wall between the first housing section 123a and the second housing section 123b) and is positioned to be movable vertically relative to the lower block 123. The upper part of the movable shaft 127 is connected to the ejector plate 126 via a connecting section 127a.

[0059] The spring 128 applies a downward force to the movable shaft 127. The spring 128 is housed in the second housing portion 123b. The spring 128 can apply a downward force to the flange portion formed at the lower end of the movable shaft 127.

[0060] The ejector rod 129 is used to move the movable shaft 127 upward relative to the lower block 123. The ejector rod 129 is positioned below the lower block 123. More specifically, the ejector rod 129 is positioned below the second housing portion 123b formed in the lower block 123. The ejector rod 129 is appropriately fixed so that it cannot move up or down. When the lower block 123 is lowered, the ejector rod 129 enters the second housing portion 123b and can push up the movable shaft 127 from below. When the movable shaft 127 is pushed up by the ejector rod 129, the ejector pin 125 rises relative to the lower mold 120. As a result, when the mold is opened, the ejector pin 125 pushes up the resin-molded lead frame 2 and allows it to be released from the lower mold 120.

[0061] The intermediate mold 130 forms the upper and lower central portion of the molding die. The intermediate mold 130 is positioned between the upper mold 110 and the lower mold 120 in the vertical direction. The intermediate mold 130 is formed in a substantially rectangular parallelepiped shape. The intermediate mold 130 has an opening 131, a resin reservoir 181, a constricted portion 182, a first cavity portion 183, a second cavity portion 184, a first air vent 185, a second air vent 186, a groove portion 187, and a gate portion 188.

[0062] The opening 131, together with the projection 111a formed on the upper mold 110, forms a guide portion for the resin material. The opening 131 is formed to penetrate the intermediate mold 130 vertically. The opening 131 is formed in a position that is vertically opposite to the pot 122a of the lower mold 120 and the projection 111a of the upper mold 110. When the intermediate mold 130 is positioned in contact with the lower surface of the upper mold 110, a predetermined gap is formed between the projection 111a of the upper mold 110 and the opening 131, thereby forming a guide portion for the resin material.

[0063] The resin reservoir 181, the constricted portion 182, the first cavity portion 183, the second cavity portion 184, the first air vent 185, and the second air vent 186 (hereinafter collectively referred to as "resin reservoir 181, etc.") shown in Figure 3 are formed on the lower surface of the intermediate mold 130. The resin reservoir 181, etc. are formed in a position opposite to the resin reservoir 171, etc. formed on the lower mold block 121. Since the resin reservoir 181, etc. are formed in a shape symmetrical in the vertical direction to the resin reservoir 171, etc. formed on the lower mold block 121, a detailed explanation of their shape will be omitted. Thus, the resin reservoir 181, etc. formed on the intermediate mold 130 are formed to correspond in the vertical direction to the resin reservoir 171, etc. formed on the lower mold block 121.

[0064] In this way, with the molds (upper mold 110, lower mold 120, and intermediate mold 130) clamped together, a cavity C1 for resin molding is formed by the first cavity portion 173 of the lower mold block 121 and the first cavity portion 183 of the intermediate mold 130. Similarly, a cavity C2 for resin molding is formed by the second cavity portion 174 of the lower mold block 121 and the second cavity portion 184 of the intermediate mold 130. In addition, a resin reservoir for retaining resin material is formed by the resin reservoir portion 171 of the lower mold block 121 and the resin reservoir portion 181 of the intermediate mold 130. Furthermore, a first air vent 185 is formed at the end of the first cavity portion 183 that is in the proximity direction, and a second air vent 186 is formed at the end of the second cavity portion 184 that is in the distance direction.

[0065] Furthermore, the resin reservoirs 171 formed in the lower mold block 121 and the resin reservoirs 181 formed in the intermediate mold 130 do not necessarily have to be arranged to correspond in the vertical direction, and can be changed according to the resin molded product being manufactured and the shape of the lead frame 2. For example, it is possible to not form the resin reservoir 171 in the lower mold block 121 and to form the resin reservoir 181 only in the intermediate mold 130.

[0066] The groove 187 forms a runner for guiding the resin material. The groove 187 is formed on the upper surface of the intermediate mold 130. The groove 187 is formed to extend horizontally from the opening 131 (above the pot 122a). The groove 187 is formed to extend in a direction appropriate to the shape of the resin molded product. As shown in Figure 4, in this embodiment, the groove 187 extending from the opening 131 to above the lower mold block 121 is successively branched. The tips of the branched grooves 187 are formed to be located above a plurality of resin reservoirs 171 formed in the lower mold block 121. In this embodiment, the groove 187 connected to one opening 131 (pot 122a) is ultimately branched into four, and each is formed to be located above four resin reservoirs 171 arranged front to back.

[0067] Furthermore, it is desirable that each branched groove 187 is formed such that the flow resistance (pressure loss) of the resin material supplied from the pot 122a is equal. For example, in this embodiment, the length of the flow path of the resin material from the pot 122a to the tip of each groove 187 is equal.

[0068] The gate portion 188 shown in Figures 3 and 4 guides the resin material from the runner portion (groove portion 187) to the cavity (first cavity portion 173 and first cavity portion 183, and second cavity portion 174 and second cavity portion 184). The gate portion 188 is formed to extend vertically upward from the resin reservoir portion 181 to the runner portion (groove portion 187).

[0069] The intermediate mold 130 can be held by either the upper mold 110 or the lower mold 120. For example, the upper mold 110 and the lower mold 120 are each provided with retaining claws (not shown) capable of holding the intermediate mold 130. By holding the intermediate mold 130 with the retaining claws of either the upper mold 110 or the lower mold 120, the intermediate mold 130 can be held by either the upper mold 110 or the lower mold 120. This allows the intermediate mold 130 to be held suspended from the upper mold 110 or placed on the lower mold 120 when the lower mold 120 is lowered.

[0070] The mold clamping mechanism 160 shown in Figure 2 moves the movable platen 150 vertically to clamp and open the mold. The mold clamping mechanism 160 is formed by a drive source such as a servo motor and an appropriate power transmission mechanism. The upper part of the mold clamping mechanism 160 is connected to the movable platen 150. By driving the mold clamping mechanism 160, the lower mold 120 can be moved (raised and lowered) arbitrarily in the vertical direction via the movable platen 150. For example, the mold can be clamped by raising the lower mold 120 toward the upper mold 110 using the mold clamping mechanism 160. The mold can also be opened by lowering the lower mold 120 away from the upper mold 110 using the mold clamping mechanism 160.

[0071] Next, using Figures 2 to 5, we will explain how the resin material is supplied to the cavity in the molding mechanism 100 configured as described above.

[0072] As shown in Figure 2, when the upper mold 110, lower mold 120, and intermediate mold 130 are clamped together, the lead frame 2 before resin molding is placed between the lower mold 120 and the intermediate mold 130. In this state, as shown in Figures 3 and 5, an exhaust passage E is formed, which is the exhaust path for air and gas discharged from the first air vents 175 and 185. The exhaust passage E is formed by being partitioned by the side surface of the pot block 122, the upper surface of the lower mold block 121, the lower surface of the intermediate mold 130, and the end face of the lead frame 2. The lead frame 2 is positioned to partially cover the upper surface of the first air vent 175 and the lower surface of the first air vent 185, so the first air vents 175 and 185 are connected to the exhaust passage E.

[0073] In this state, the molten resin material present in the pot 122a is pushed up by the plunger 124. As a result, the molten resin material fills the cavity through the aforementioned cal section, runner section, and gate section 188.

[0074] Specifically, the resin material in the pot 122a, pushed up by the plunger 124, flows through the groove 187 (runner section) shown in Figures 3 and 4, and is supplied to the tip of the branched groove 187. The resin material that reaches the tip of the groove 187 flows downward through the gate section 188 and is supplied to the resin reservoir (resin reservoir section 171 and resin reservoir section 181).

[0075] The throttling sections 172 and 182, which are connected to the resin reservoir, are formed such that the cross-sectional area of ​​the flow path for the resin material is narrower compared to the resin reservoir. Therefore, the resin material supplied from the gate section 188 to the resin reservoir temporarily remains in the resin reservoir. After a certain amount of resin material has been supplied to the resin reservoir, the resin material is supplied to the left and right cavities (cavity C1 and cavity C2) via the throttling sections 172 and 182, and is distributed fairly evenly.

[0076] As shown in Figure 5, the resin material flowing into the left and right cavities circulates within the cavities from the resin reservoir toward the left and right. At this time, the air and gas in the left cavity C1 are discharged to the outside of cavity C1 via the first air vents 175 and 185 shown in Figures 3 and 5. Specifically, the air and gas discharged to the outside of cavity C1 via the first air vents 175 and 185 are then discharged to the outside of the mold via the exhaust passage E. In addition, the air and gas in the right cavity C2 are discharged to the outside of cavity C2 via the second air vents 176 and 186.

[0077] In this embodiment, the resin material is supplied to the left and right cavities (cavity C1 and cavity C2) from a gate portion 188 formed at the midpoint between the left and right cavities, which are formed longitudinally across the width of the lead frame 2. By configuring it this way, the length of the resin material flow path (length from the gate portion 188 to the end of the cavity) can be shortened compared to, for example, a case where the gate portion is formed at one end of the lead frame 2 (e.g., the left end) and the resin material is flowed from this gate portion to the other end of the lead frame 2 (e.g., the right end). Specifically, by providing the gate portion 188 in the center of the left and right of the lead frame 2 as in this embodiment, the length of the resin material flow path from the gate portion can be reduced by about half compared to a case where the gate portion is formed at the end of the lead frame 2.

[0078] In this way, by shortening the length of the resin material flow path (filling distance) in the cavity, even if there are differences in the filling speed of the resin material in each cavity, variations in the timing of completion of filling for each cavity can be suppressed. For example, as shown in Figure 5, the filling of resin material into multiple cavities C1 arranged in a front-to-back manner can be completed almost simultaneously.

[0079] Since the filling of the resin material is completed almost simultaneously, it is possible to prevent the resin material from filling some cavities at high speed. This prevents deformation of the bonding wire formed on the lead frame 2.

[0080] Furthermore, in this embodiment, a method of supplying resin material from above via the gate portion 188, rather than from the side of the cavity (top gate method), is employed. This allows space to be secured on the pot block 122 side of the cavity C1 to form the first air vents 175 and 185. This improves the exhaust capacity during resin molding and suppresses the generation of voids and the like.

[0081] In the above embodiment, an example was shown in which the longitudinal lengths of the first cavity C1 and the second cavity C2 are the same. However, the lengths of the first cavity C1 and the second cavity C2 may be different. For example, considering the flow resistance of the resin material in the first cavity C1 and the second cavity C2, the cavity with higher flow resistance may be formed to be shorter than the cavity with lower flow resistance.

[0082] In this embodiment, a method of supplying resin material from above the cavity via the gate portion 188 (top gate method) was described as an example, but the present invention is not limited to this, and the supply path of resin material to the cavity can be arbitrarily changed. For example, it is also possible to supply resin material from below the cavity via the gate portion. In this case, for example, cavities may be formed on the lower surface of the upper mold and the upper surface of the intermediate mold, a cal portion and a runner portion may be formed on the lower surface of the intermediate mold and the upper surface of the lower mold, and a gate portion may be formed below the cavity in the intermediate mold.

[0083] <Second Embodiment> Next, a second embodiment will be described using Figures 6 and 7.

[0084] In the second embodiment, the mold (particularly the lower mold 120 and the intermediate mold 130) has a different shape for the cavity C3 compared to the first embodiment (see Figures 3 and 4). Specifically, in the first embodiment, one cavity (cavity C1 and cavity C2) is formed on each side of the gate portion 188, whereas in the second embodiment, one cavity C3 is formed so as to straddle the gate portion 188 from left to right. The specific configuration will be described below.

[0085] A cavity portion 173A is formed on the upper surface of the lower mold block 121. The cavity portion 173A is formed in an elongated shape, extending from left to right. The cavity portion 173A is formed to be of equal length from the gate portion 188 on both sides. Both ends of the cavity portion 173A in the left-right direction are connected to the first air vent 185 and the second air vent 186, respectively.

[0086] A cavity portion 183A is formed on the lower surface of the intermediate mold 130. The cavity portion 183A is formed in a shape that is vertically symmetrical to the cavity portion 173A formed on the lower mold block 121.

[0087] In this way, with the mold clamped, the cavity C3 is formed by the cavity portion 173A of the lower mold block 121 and the cavity portion 183A of the intermediate mold 130.

[0088] A gate portion 188 is connected to the center of the cavity C3 in the left-right direction. Thus, in the second embodiment, the resin material supplied from the gate portion 188 flows into the cavity C3 without passing through the resin reservoir.

[0089] Furthermore, when a single cavity C3 is formed extending from the left to the right of the gate portion 188 in this manner, the portion of the cavity C3 to the left of the gate portion 188 (towards the pot block 122) corresponds to one embodiment of the first cavity of the present invention. Also, the portion of the cavity C3 to the right of the gate portion 188 (opposite the pot block 122) corresponds to one embodiment of the second cavity of the present invention.

[0090] In the above embodiment, an example was shown in which the gate portion 188 is connected to the center of the cavity C3 in the left-right direction, but the position of the gate portion 188 is not particularly limited. For example, the position of the gate portion 188 can be adjusted left or right, taking into consideration the direction in which the resin material flowing from the gate portion 188 into the cavity C3 is likely to flow. Specifically, if the resin material flowing through the runner portion (groove portion 187) into the cavity C3 is likely to flow to the right within the cavity C3 due to inertia, the gate portion 188 may be positioned to the left of the center of the cavity C3.

[0091] <Third Embodiment> Next, a third embodiment will be described using Figure 8.

[0092] The mold according to the third embodiment differs from the first embodiment (see Figure 4) in the number of cavities connected to the end of the runner portion (groove portion 187). Specifically, in the first embodiment, two cavities (one first cavity C1 and one second cavity C2) are connected to one branched groove portion 187, whereas in the second embodiment, four cavities (two first cavities C1 and two second cavities C2) are connected. The specific configuration will be described below.

[0093] In the third embodiment, four cavities are connected to the resin reservoir (resin reservoir portion 171). Specifically, two first cavities C1 (first cavity portion 173) are formed on the left side of one resin reservoir portion 171, arranged front to back. The resin reservoir portion 171 is connected to the right end of the two first cavity portions 173. Also, two second cavities C2 (second cavity portion 174) are formed on the right side of one resin reservoir portion 171, arranged front to back. The resin reservoir portion 171 is connected to the left end of the two second cavity portions 174.

[0094] In this way, it is also possible to supply resin material from one gate portion 188 to multiple first cavities C1 and multiple second cavities C2.

[0095] The number of cavities connected to one gate section 188 is not particularly limited. Also, the number of first cavities C1 and second cavities C2 connected to one gate section 188 may be different from each other.

[0096] <Fourth Embodiment> Next, the fourth embodiment will be described using Figure 9.

[0097] The mold according to the fourth embodiment differs from the third embodiment (see Figure 8) in that the ends of the runner portion (groove portion 187) are connected to a plurality (two in the illustrated example) of gate portions 188. Specifically, in the mold according to the fourth embodiment, two gate portions 188 are formed at the ends of the branched groove portion 187. The two gate portions 188 are each connected to an adjacent resin reservoir portion 171. The resin reservoir portion 171 is connected to four cavities (two first cavities C1 and two second cavities C2), similar to the third embodiment.

[0098] As shown in the third embodiment (see Figure 8) and the fourth embodiment (see Figure 9), the flow path of the resin material supplied to the cavity can be arbitrarily changed. For example, compared to the first embodiment (see Figure 4), the third embodiment (see Figure 8) and the fourth embodiment (see Figure 9) can supply resin material to more cavities from each branched runner section (groove 187). This configuration reduces the number of runner sections and the overall length of the runner sections. This makes it possible to reduce the amount of resin material used and to reduce the number of parts (ejector pins) used to remove excess resin that has hardened in the runner sections.

[0099] <Fifth Embodiment> Next, the fifth embodiment will be described using Figure 10.

[0100] The mold according to the fifth embodiment differs from the first embodiment (see Figure 5) in the discharge path for air and gas within the cavity. Specifically, in the first embodiment, the air and gas discharged from the first air vent 175 are guided in the front-rear direction through the exhaust passage E partitioned by the side surface of the pot block 122 and discharged to the outside of the mold. In contrast, in the fifth embodiment, the air and gas discharged from the first air vent 175 are guided to the right through the exhaust passage E1 and discharged to the outside from the right end of the mold.

[0101] The exhaust passage E1 shown in Figure 10 is formed by recessing at least one of the upper surface of the lower mold 120 (lower mold block 121) or the lower surface of the intermediate mold 130. For example, in the example in Figure 10, the exhaust passage E1 is shown formed by recessing the upper surface of the lower mold block 121, but the exhaust passage E1 may also be formed by recessing the lower surface of the intermediate mold 130 in the same way. The exhaust passage E1 is connected to the first air vent 175. The exhaust passage E1 is formed to branch forward and backward from the first air vent 175 and then extend through the space between the first cavity C1 and the second cavity C2, which are arranged front to back, to the right end of the lower mold block 121.

[0102] In the fifth embodiment, the air or gas discharged from the cavity via the first air vent 175 is guided to the right (away from the pot block 122) via the exhaust passage E1 and discharged to the outside of the mold from the right end of the mold.

[0103] In the example shown in Figure 10, an exhaust passage E1 is shown branching forward and backward from the first air vent 175. However, it is also possible to form the exhaust passage E1 only on either the forward or backward side of the first air vent 175, without branching forward or backward from the first air vent 175.

[0104] Furthermore, the exhaust path for air and gas within the cavity is not limited to the exhaust path E in the first embodiment and the exhaust path E1 in the fifth embodiment; any path can be arbitrarily set.

[0105] <Note> The resin molding apparatus of the first aspect of this disclosure comprises a mold having an upper mold 110, a lower mold 120 disposed below the upper mold 110 and having a pot block 122 on which a pot 122a for containing resin material is formed, and an intermediate mold 130 disposed between the upper mold 110 and the lower mold 120, and a clamping mechanism 160 for clamping the mold, wherein the mold has a runner portion (groove portion 187) formed by the upper surface of the intermediate mold 130 and the lower surface of the upper mold 110 for guiding the resin material supplied from the pot 122a, and a gate portion 188 formed in the intermediate mold 130 for guiding the resin material from the runner portion to the lower surface of the intermediate mold 130, A first cavity C1 is formed by the upper surface of the lower mold 120 and the lower surface of the intermediate mold 130, is connected to the gate portion 188, and is formed in an elongated shape extending from the gate portion 188 in the approaching direction toward the pot block 122. A second cavity C2 is formed by the upper surface of the lower mold 120 and the lower surface of the intermediate mold 130, is connected to the gate portion 188, and is formed in an elongated shape extending from the gate portion 188 in the distance away from the pot block 122. According to the resin molding apparatus 1 of the first aspect of this disclosure, the time difference in the completion of filling of the resin material supplied from one pot 122a to multiple cavities can be reduced. That is, by shortening the length of the cavities extending from the gate portion 188 in the approaching and distance directions, the filling distance of the resin material can be shortened. This makes it possible to suppress variations in the timing of completion of filling each cavity (for example, multiple cavities C1 and C2 arranged in front of and behind each other (see Figure 5)) even if there are differences in the filling speed of the resin material. This makes it possible to suppress an increase in the filling speed of the resin material in some cavities, and thus prevent deformation of the bonding wire, etc.

[0106] In a resin molding apparatus 1 with a second side surface that follows a first side surface, the length of the first cavity C1 in the longitudinal direction is formed to be the same as the length of the second cavity C2 in the longitudinal direction. According to the resin molding apparatus 1 with a second side surface of this disclosure, it is possible to suppress variations in the timing of completion of filling the first cavity C1 and the second cavity C2 with resin material.

[0107] In a resin molding apparatus 1 with a third side surface corresponding to a first or second side surface, a first air vent 175 and a first air vent 185 are formed at the end of the first cavity C1 in the proximity direction, and a second air vent 176 and a second air vent 186 are formed at the end of the second cavity C2 in the distance direction. According to the resin molding apparatus 1 with a third side surface of this disclosure, the exhaust capacity of the first cavity C1 and the second cavity C2 can be improved, and the generation of voids and the like can be suppressed.

[0108] In the resin molding apparatus 1 with a fourth side surface corresponding to the third side surface, the first air vent 175 and the first air vent 185 are connected to an exhaust passage E partitioned by the side surface of the pot block 122. According to the resin molding apparatus 1 with a fourth side surface of this disclosure, exhaust from the first cavity C1 can be performed by utilizing the space on the side of the pot block 122.

[0109] In a fifth-sided resin molding apparatus 1 that conforms to any of the first to fourth sides, the mold has resin reservoirs 171 and 181 formed by the upper surface of the lower mold 120 and the lower surface of the intermediate mold 130, which allow the resin material supplied from the gate portion 188 to accumulate before guiding it to the first cavity C1 and the second cavity C2. According to the fifth-sided resin molding apparatus 1 of this disclosure, by allowing the resin material to accumulate, the uniformity of the resin material supplied to the first cavity C1 and the second cavity C2 can be achieved.

[0110] In a resin molding apparatus 1 with a sixth side surface that conforms to any of the first to fifth side surfaces, at least one of the first cavity C1 or the second cavity C2 is formed in multiple locations for one gate portion 188. According to the resin molding apparatus 1 with a sixth side surface of the present disclosure, the number of gates and runner portions in the cavity can be reduced, and the overall length of the runner portion can be shortened.

[0111] The method for manufacturing a resin molded product according to the seventh aspect of this disclosure is a method for manufacturing a resin molded product using any of the resin molding apparatus 1 according to the first to sixth aspects, and includes: clamping the mold to perform resin molding; and opening the mold to unload the resin molded product. According to the method for manufacturing a resin molded product according to the seventh aspect of this disclosure, the time difference in the completion of filling of the resin material supplied from one pot 122a to multiple cavities can be reduced.

[0112] 1. Resin molding apparatus 110 Upper mold 120 Lower mold 122 Pot block 130 Intermediate mold 173 First cavity section 174 Second cavity section 175 First air vent 176 Second air vent 183 First cavity section 184 Second cavity section 185 First air vent 186 Second air vent 187 Groove section 188 Gate section C1 First cavity C2 Second cavity E Exhaust passage

Claims

A molding die comprising: an upper mold; a lower mold positioned below the upper mold and having a pot block in which a pot for containing resin material is formed; and an intermediate mold positioned between the upper mold and the lower mold. A clamping mechanism for clamping the aforementioned mold, Equipped with, The aforementioned mold includes: A runner portion formed by the upper surface of the intermediate mold and the lower surface of the upper mold, which guides the resin material supplied from the pot, A gate portion formed in the intermediate mold guides the resin material from the runner portion to the lower surface of the intermediate mold, A first cavity is formed by the upper surface of the lower mold and the lower surface of the intermediate mold, is in contact with the gate portion, and is formed in an elongated shape extending from the gate portion in the direction approaching the pot block, A second cavity is formed by the upper surface of the lower mold and the lower surface of the intermediate mold, is in contact with the gate portion, and is formed in an elongated shape extending from the gate portion in a remote direction away from the pot block, It is formed Resin molding equipment. 　 The length of the first cavity in the longitudinal direction is formed to be the same as the length of the second cavity in the longitudinal direction. The resin molding apparatus according to claim 1. 　 In the first cavity, a first air vent is formed at the end facing the proximity direction. A second air vent is formed at the end of the second cavity that is in the remote direction. A resin molding apparatus according to claim 1 or claim 2. 　 The first air vent is connected to an exhaust passage partitioned on the side of the pot block. The resin molding apparatus according to claim 3. 　 The mold has a resin reservoir formed by the upper surface of the lower mold and the lower surface of the intermediate mold, which holds the resin material supplied from the gate and then guides it to the first cavity and the second cavity. A resin molding apparatus according to any one of claims 1 to 4. 　 At least one of the first cavity or the second cavity is formed in multiple locations relative to one of the gate portions. A resin molding apparatus according to any one of claims 1 to 5. 　 A method for manufacturing a resin molded product using a resin molding apparatus according to any one of claims 1 to 6, The aforementioned mold is clamped and resin is molded, The molding die is opened and the resin molded product is unloaded. A method for manufacturing resin molded products containing [a specific component].

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