Resin-molded article manufacturing method

Abstract

Provided is a resin-molded article manufacturing method with which it is possible to improve the manufacturing efficiency of a resin-molded article.　In the resin-molded article manufacturing method, an object to be molded is resin-molded using a mold including a lower mold having a protrusion to be fitted to the object to be molded and an upper mold having a cavity. The method comprises: a placement step in which the object to be molded is placed on the lower mold; a first mold clamping step in which the lower mold and the upper mold are moved relative to each other to clamp the mold, thereby fitting the object to be molded and the protrusion to each other; a mold opening step in which, after the first mold clamping step, the upper mold and the lower mold are moved relative to each other to open the mold; a resin material supply step in which, after the mold opening step, a resin material is supplied to a resin receiving portion formed in the lower mold; a second mold clamping step in which the lower mold and the upper mold are moved relative to each other to clamp the mold; and a step in which, after the second mold clamping step, the object to be molded is resin-molded by supplying the resin material supplied to the resin receiving portion to the cavity.

Description

Manufacturing method for resin molded products

[0001] The present invention relates to a technique for manufacturing a resin molded product.

[0002] Patent Document 1 discloses a technique in which a lead frame is placed in a lower mold, and then the mold is clamped to perform resin molding. The lower mold is formed with concave and convex portions (e.g., positioning pins) that fit with the lead frame. The concave and convex portions are formed in positions that correspond to the dimensions of the lead frame when it is heated to a predetermined temperature and thermally expanded. Therefore, unless the temperature of the lead frame is sufficiently raised, the lead frame cannot be fitted with the concave and convex portions, and the lead frame cannot be properly placed in the lower mold.

[0003] Therefore, the technology described in Patent Document 1 employs a configuration in which a pressing mechanism is used to press the lead frame against the lower mold. By using the pressing mechanism, the contact area between the lead frame and the lower mold can be increased, and the lead frame can be sufficiently heated by a heater provided in the lower mold.

[0004] Japanese Patent Application Laid-Open No. 2001-77135

[0005] However, with the technology described in Patent Document 1, after the lead frame is pressed against the lower die by the pressing mechanism, it takes some time for the lead frame to be sufficiently heated, which may reduce the production efficiency of resin molded products.

[0006] The present invention has been made in view of the above circumstances, and the problem to be solved by the present invention is to provide a method for manufacturing a resin molded product that can improve the production efficiency of the resin molded product.

[0007] The problem that the present invention aims to solve is as described above, and in order to solve this problem, the method for manufacturing a resin molded product of the present invention is a method for resin molding a resin object using a molding die including a lower die having a protrusion formed thereon that fits with the object to be molded, and an upper die having a cavity, the method including the following steps: a loading step for loading the object to be molded onto the lower die; a first clamping step for moving the lower die and the upper die relative to each other and clamping them to fit the object to be molded with the protrusion; a mold opening step for moving the upper die and the lower die relative to each other to open the die after the first clamping step; a resin material supplying step for supplying a resin material to a resin storage section formed in the lower die after the mold opening step; a second clamping step for moving the lower die and the upper die relative to each other and clamping the die; and a step for resin molding the object to be molded by supplying the resin material supplied to the resin storage section to the cavity after the second clamping step.

[0008] According to the present invention, it is possible to improve the production efficiency of resin molded products.

[0009] 1 is a schematic plan view showing the overall configuration of a resin molding apparatus according to one embodiment; a schematic front sectional view showing the configuration of a molding mechanism; a schematic front sectional view showing the configuration of a molding die, a transfer mechanism, and a lead frame; a flowchart showing a method for manufacturing a resin molded product according to one embodiment; (a) a view showing a state in which a lead frame is carried into a molding die by a loader; (b) a view showing a state in which first mold clamping is performed; (a) a view showing a state in which a lead frame is placed on a lower die; (b) a view showing a state in which the lead frame has been pressed down.

[0010] In the following explanation, the directions indicated by arrows U, D, L, R, F, and B in the figure will be defined as upward, downward, leftward, rightward, forward, and backward, respectively.

[0011] <Overall Configuration of Resin Molding Apparatus 1> First, the configuration of the resin molding apparatus 1 will be described using Figure 1. The resin molding apparatus 1 resin-encapsulates electronic elements such as semiconductor chips (hereinafter simply referred to as "chips 2a" (see Figure 2)) to manufacture resin molded products. In particular, this embodiment illustrates a resin molding apparatus 1 that performs resin molding using a transfer molding method. Note that the chips 2a are not shown anywhere except in Figure 2.

[0012] The resin molding apparatus 1 includes, as its components, a supply module 10, a resin molding module 20, and an unloading module 30. Each component is detachable and replaceable with respect to the other components.

[0013] <Supply Module 10> The supply module 10 supplies lead frames 2, which are a type of substrate with chips 2a mounted thereon, and resin tablets T to the resin molding module 20. The lead frames 2 are one embodiment of the molding object according to the present invention. The lead frames 2 used in this embodiment are relatively thick (so-called thick lead frames). For example, the lead frames 2 may have a thickness of 0.5 mm or more, or 1.0 mm or more. While the present embodiment uses lead frames 2 as an example of a substrate, various other substrates (glass epoxy substrates, ceramic substrates, resin substrates, metal substrates, etc.) can also be used. The supply module 10 primarily includes a frame sending unit 11, a frame supply unit 13, a resin material supply mechanism 14, a loader 17, and a control unit 18.

[0014] The frame sending section 11 sends out the lead frames 2 that are not sealed with resin and are housed in an in-magazine unit (not shown) to the frame supplying section 13. The frame supplying section 13 receives the lead frames 2 from the frame sending section 11, aligns the received lead frames 2 appropriately, and passes them to the loader 17.

[0015] The resin material supply mechanism 14 supplies the resin tablets T to a loader 17 (described later). The resin material supply mechanism 14 can align a plurality of resin tablets T and deliver them to the loader 17.

[0016] The loader 17 transports the lead frames 2 and resin tablets T received from the frame supply unit 13 and the resin material supply mechanism 14 to the resin molding module 20. The loader 17 is equipped with a heater plate (not shown) for preheating the lead frames 2. The heater plate is heated by a heating device while the loader 17 is on standby. The heater plate can also heat the lead frames 2 while the loader 17 is transporting the lead frames 2.

[0017] The loader 17 is also provided with a cleaning mechanism 17a for cleaning the molding dies (lower die 110 and upper die 120) described below. The cleaning mechanism 17a may be, for example, a dust collection mechanism capable of sucking up dust adhering to the surfaces of the molding dies. The cleaning mechanism 17a is provided, for example, at the front end of the loader 17.

[0018] The control unit 18 controls the operation of each module of the resin molding apparatus 1. The control unit 18 controls the operations of the supply module 10, the resin molding module 20, and the carry-out module 30. The control unit 18 can also be used to arbitrarily change (adjust) the operation of each module.

[0019] In this embodiment, an example is shown in which the control unit 18 is provided in the supply module 10, but the control unit 18 can also be provided in other modules. It is also possible to provide multiple control units 18. For example, it is possible to provide a control unit 18 for each module or device, and to control the operations of each module individually while linking them together.

[0020] <Resin molding module 20> The resin molding module 20 resin-seals the chip 2a mounted on the lead frame 2. In this embodiment, two resin molding modules 20 are arranged side by side. Note that the number of resin molding modules 20 may be one, or three or more. By using multiple resin molding modules 20 to resin-seal the lead frame 2 in parallel, the manufacturing efficiency of resin molded products can be improved. The resin molding module 20 mainly includes a molding mechanism 100.

[0021] The molding mechanism 100 mainly includes a molding die (a lower die 110 and an upper die 120) and a die clamping mechanism 140 (see FIG. 2).

[0022] The molding dies (lower die 110 and upper die 120) use molten resin material to resin-encapsulate the chip 2a mounted on the lead frame 2. The molding dies include a pair of upper and lower dies, namely, the lower die 110 and the upper die 120 (see FIG. 2, etc.).

[0023] The mold clamping mechanism 140 (see FIG. 2) clamps or opens the molding dies (lower die 110 and upper die 120) by moving the lower die 110 up and down. The specific configuration of the molding mechanism 100 will be described later.

[0024] <Unloading Module 30> The unloading module 30 receives and unloads the resin-sealed lead frame 2 from the resin molding module 20. The unloading module 30 mainly includes an unloader 31 and a substrate accommodating section 32.

[0025] The unloader 31 holds the resin-sealed lead frame 2 and carries it out to the substrate accommodating section 32. The substrate accommodating section 32 accommodates the resin-sealed lead frame 2.

[0026] <Forming Mechanism 100> Next, a specific configuration of the forming mechanism 100 will be described with reference to FIGS. 2 and 3. FIG.

[0027] 2 is a diagram schematically illustrating the configuration of the molding mechanism 100. Also, FIG. 3 is a diagram schematically illustrating the molding dies (lower die 110 and upper die 120), transfer mechanism 150, and lead frame 2 extracted from the configuration shown in FIG.

[0028] As shown in FIG. 2, the molding mechanism 100 mainly includes molding dies (a lower die 110 and an upper die 120 ), an upper fixed platen 130 , a die clamping mechanism 140 , and a transfer mechanism 150 .

[0029] 2 and 3, the lower mold 110 forms the lower part of the molding die and is mainly provided with a pot 111, a pilot pin 112, a dam portion 113, and a lower mold heater 114.

[0030] The pot 111 is a portion that accommodates the resin tablet T. The pot 111 is one embodiment of a resin accommodation portion according to the present invention. The pot 111 is formed so as to penetrate the lower mold 110 from top to bottom. The pot 111 is formed in the center of the lower mold 110 from left to right. Multiple pots 111 are formed so as to be lined up front and back (not shown). In this embodiment, lead frames 2 are arranged on the left and right of the pot 111 of the lower mold 110, which is a so-called two-piece configuration. However, the lower mold 110 may be configured so that only one lead frame 2 is arranged therein, or so that three or more lead frames 2 are arranged therein.

[0031] The pilot pin 112 shown in FIG. 3 is used to align the position of the lead frame 2 with respect to the lower mold 110. The pilot pin 112 is one embodiment of the protrusion and positioning portion according to the present invention. The pilot pin 112 is formed in a cylindrical shape with its axis oriented in the vertical direction. The pilot pin 112 is formed so as to protrude upward from the upper surface of the lower mold 110. The pilot pin 112 is formed at a position corresponding to the through hole 2b formed in the lead frame 2. The height of the upper end of the pilot pin 112 is formed to be higher than the height of the upper end of a dam portion 113, which will be described later. The number of pilot pins 112 is not particularly limited, and any number of pilot pins can be formed.

[0032] The dam portion 113 is for controlling the flow of the resin material (molten resin tablet T) when resin molding is performed on the lead frame 2. The dam portion 113 is one embodiment of the protrusion and resin flow control portion according to the present invention. The dam portion 113 is formed so as to protrude upward from the upper surface of the lower mold 110. The position and shape of the dam portion 113 can be determined arbitrarily depending on the shape of the lead frame 2 and the shape of the product (resin molded product), etc.

[0033] The dam portion 113 is formed, for example, at a position corresponding to the gap X between the first portion 2c and the second portion 2d of the lead frame 2. The width of the dam portion 113 (the width in the left-right direction in the illustrated example) is formed to be approximately the same as the width of the gap X. The dam portion 113 may be formed in a tapered shape such that the width in a predetermined direction decreases from the lower end to the upper end, so that it can be easily fitted into the gap X. By fitting the dam portion 113 into the gap X, the flow of resin material that attempts to flow through the gap X can be blocked.

[0034] In this way, by forming the dam portion 113 at an appropriate position, the flow of the resin material can be controlled, which makes it possible to, for example, prevent the resin material from leaking out of the molding die or to mold the resin material into a desired shape.

[0035] Here, the dam portion 113 is formed in a position and shape that corresponds to the shape of the lead frame 2 in order to be fitted into the lead frame 2. More specifically, the lead frame 2 is heated and thermally expanded during resin molding, so the dam portion 113 is formed in a position and shape that allows it to be fitted into the lead frame 2 in a thermally expanded state.

[0036] 2 is for heating the lower mold 110 during resin molding. The lower mold heater 114 is provided inside the lower mold 110.

[0037] 2 and 3 forms the upper part of the molding die. The upper die 120 mainly includes a recess 121, a resin flow path 122, and an upper die heater 123.

[0038] The recess 121 is a portion that forms a cavity, which is a space for resin sealing, between the lead frame 2 and the upper mold 120 when the lead frame 2 is placed on the lower mold 110 and the lower mold 110 and upper mold 120 are closed. A chip 2a fixed to the lead frame 2 is housed in the cavity, and the chip 2a is resin-sealed with a resin material supplied to the cavity. The recess 121 is formed by recessing the lower surface of the upper mold 120 upward. The recess 121 is formed in a position and shape that corresponds to the shape of the product (resin molded product), etc.

[0039] The resin flow path 122 is a portion that guides the molten resin tablet T (resin material) to the recess 121 (cavity) when the lead frame 2 is placed on the lower mold 110 and the lower mold 110 and upper mold 120 are closed. The resin flow path 122 is formed by recessing the lower surface of the upper mold 120 upward. The resin flow path 122 is formed so as to connect the pot 111 and the recess 121 (cavity) when the lower mold 110 and upper mold 120 are closed.

[0040] 2 is for heating the upper mold 120 when resin molding is performed. The upper mold heater 123 is provided inside the upper mold 120.

[0041] The upper fixed platen 130 supports the upper mold 120. The upper fixed platen 130 is fixed at a predetermined position by appropriate members (supports, etc.). The upper mold 120 is fixed to the lower surface of the upper fixed platen 130. This fixes the upper mold 120 at the predetermined position so that it cannot move.

[0042] The mold clamping mechanism 140 lifts the lower mold 110 and clamps the lower mold 110 and the upper mold 120 together. The mold clamping mechanism 140 mainly includes a movable platen 141 and a drive mechanism 142.

[0043] The movable platen 141 supports the lower mold 110. The movable platen 141 is arranged so as to be movable in the vertical direction. The lower mold 110 is fixed to the upper surface of the movable platen 141.

[0044] The drive mechanism 142 moves the lower mold 110 in the up and down direction. The drive mechanism 142 is formed by, for example, a drive source such as a servo motor and an appropriate power transmission mechanism. The upper part of the drive mechanism 142 is connected to the movable platen 141. By driving the drive mechanism 142, the lower mold 110 can be moved (raised and lowered) in the up and down direction as desired via the movable platen 141. For example, the drive mechanism 142 can raise the lower mold 110 toward the upper mold 120 to close the mold. Furthermore, the drive mechanism 142 can lower the lower mold 110 away from the upper mold 120 to open the mold.

[0045] 2 and 3, the transfer mechanism 150 supplies the resin material to the cavity and mainly includes a plunger 151 and a transfer driver (not shown).

[0046] The plunger 151 injects and supplies the resin tablet T (resin material) contained in the pot 111 to the cavity. The plunger 151 is arranged in the pot 111 so as to be able to move up and down (raise and lower).

[0047] The transfer drive unit (not shown) is a drive source that moves the plunger 151 in the up and down direction. The transfer drive unit (not shown) can be configured by, for example, a servo motor, an air cylinder, or the like.

[0048] <Overview of Operation of Resin Molding Apparatus 1> Next, an overview of the operation of the resin molding apparatus 1 configured as described above (a method for manufacturing a resin molded product using the resin molding apparatus 1) will be described using Figures 1 and 4 to 6.

[0049] First, the lead frames 2 and the resin tablets T are delivered to the loader 17 (step S11 in FIG. 4). Specifically, in the supply module 10 shown in FIG. 1, the frame delivery unit 11 delivers the lead frames 2 stored in an in-magazine unit (not shown) to the frame supply unit 13. The frame supply unit 13 aligns the received lead frames 2 appropriately and delivers them to the loader 17.

[0050] Furthermore, the resin material supply mechanism 14 delivers to the loader 17 the number of resin tablets T required for one resin molding in the resin molding module 20 .

[0051] Next, the loader 17 is caused to enter the molding die (step S12 in FIG. 4 ). Specifically, after receiving the lead frame 2 and the resin tablet T, the loader 17 moves to the resin molding module 20 while preheating the lead frame 2. Then, as shown in FIG. 5A , the loader 17 moves from the rear to the molding die of the molding mechanism 100. The loader 17 then places the lead frame 2 on the upper surface of the lower die 110 (step S13 in FIG. 4 ). At this time, as shown in FIG. 6A , the upper ends of the pilot pins 112 are inserted into the through holes 2 b of the lead frame 2, thereby positioning the lead frame 2 relative to the lower die 110. At this time, the loader 17 does not supply the resin tablet T to the pot 111 of the lower die 110, but continues to hold the resin tablet T.

[0052] 6A, it is assumed that the temperature of the lead frame 2 has not yet risen to the temperature required for resin molding when the loader 17 places the lead frame 2 on the lower mold 110. Therefore, the lead frame 2 has not thermally expanded sufficiently, and the position and dimensions of the gap X in the lead frame 2 do not correspond to the position and dimensions of the dam portion 113. Therefore, the dam portion 113 does not completely fit into (fit with) the gap X, and a gap is formed between the lead frame 2 and the upper surface of the lower mold 110.

[0053] After placing the lead frame 2 on the lower die 110, the loader 17 temporarily retreats from the molding die (step S14 in FIG. 4).

[0054] Next, the mold clamping mechanism 140 clamps the molding die (first mold clamping, step S15 in FIG. 4). Specifically, the mold clamping mechanism 140 is driven to raise the lower mold 110 toward the upper mold 120. The mold clamping force at this time is set to be smaller than the mold clamping force used in the second mold clamping (step S20) described below. When the lower mold 110 approaches the upper mold 120, the lead frame 2 is sandwiched between the lower mold 110 and the upper mold 120, as shown in FIG. 5(b).

[0055] 6(b), the lead frame 2 placed on the lower mold 110 is pressed downward by the upper mold 120. When the lead frame 2 is pressed downward, the lead frame 2 is fitted into the dam portion 113 while slightly moving and / or deforming depending on the position or shape of the dam portion 113. In this way, the lead frame 2 is set in a state where it contacts the upper surface of the lower mold 110. Note that this mold clamping in step S15 may be referred to as "first mold clamping" hereinafter.

[0056] Next, the mold is opened by the mold clamping mechanism 140 (step S16 in FIG. 4). Specifically, the mold clamping mechanism 140 is driven to lower the lower mold 110 so that the lower mold 110 is separated from the upper mold 120.

[0057] Next, the loader 17 is again advanced into the mold (step S17 in FIG. 4). At this time, the cleaning mechanism 17a provided on the loader 17 may be used to clean (collect) the surfaces of the mold (the upper surface of the lower mold 110 and the lower surface of the upper mold 120). This improves the quality of the resin molded product. After the loader 17 has advanced into the mold, the resin tablet T held by the loader 17 is stored (set) in the pot 111 of the lower mold 110 (step S18 in FIG. 4). This supplies the resin tablet T to the mold.

[0058] After the resin tablet T is stored in the pot 111, the loader 17 retreats rearward from the molding die (step S19 in FIG. 4).

[0059] Next, the mold clamping mechanism 140 clamps the casting mold again (step S20 in FIG. 4). Note that this mold clamping in step S20 may be referred to as "second mold clamping" below.

[0060] Next, the transfer mechanism 150 injects the resin material into the cavity (step S21 in FIG. 4). Specifically, the resin tablet T stored in the pot 111 is heated and melted by heaters (lower die heater 114 and upper die heater 123) provided in the molding die. The transfer mechanism 150 raises the plunger 151 to inject the melted resin tablet T (resin material) into the cavity.

[0061] After the resin material is injected by the transfer mechanism 150, by waiting until a predetermined time has elapsed, the resin material is hardened and the chip 2a of the lead frame 2 can be resin-sealed.

[0062] Next, the mold is opened by the mold clamping mechanism 140 (step S22 in FIG. 4). This allows the resin-sealed lead frame 2 to be released from the mold. Thereafter, the lead frame 2 is removed from the mold (step S23 in FIG. 4). Specifically, the lead frame 2 is removed from the mold by the unloader 31 shown in FIG. 1 and stored in the substrate storage section 32 of the carry-out module 30. In this manner, the resin-sealed lead frame 2 (resin molded product) is manufactured.

[0063] As described above, in this embodiment, the lead frame 2 can be fitted into the dam portion 113 by the first mold clamping (step S15), so that even if the lead frame 2 is not sufficiently heated, the lead frame 2 can be set in the lower mold 110. This reduces the time required to preheat the lead frame 2, thereby improving the production efficiency of resin molded products.

[0064] Furthermore, since the lead frame 2 can be set in the lower mold 110 using the mold clamping mechanism 140, there is no need to provide a separate mechanism for pressing down the lead frame 2, which allows for cost reduction.

[0065] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and appropriate modifications are possible within the scope of the technical idea of ​​the invention described in the claims.

[0066] For example, in the above embodiment, an example was shown in which a relatively thick lead frame 2 is used, but the thickness of the lead frame 2 is not particularly limited.

[0067] The lead frame 2 can also be formed by fixing a plurality of stacked plate-like members (frames) together. When the lead frame 2 has such a stacked structure, it is expected that it will take a long time to set the lead frame 2 in the molding die because it will be difficult to sufficiently heat the lead frame 2 by preheating and the temperature difference between the top and bottom will be greater, which will increase the time required to heat the entire lead frame to the same temperature. However, according to the manufacturing method for a resin molded product of this embodiment, the lead frame 2 can be properly set in the lower mold 110 in a short time by the first mold clamping (step S15).

[0068] In the above embodiment, a dust collection mechanism is described as a specific example of the cleaning mechanism 17a, but the cleaning mechanism 17a is not limited to this and may have any configuration. For example, the cleaning mechanism 17a may be configured as a brush or the like that removes dust adhering to the casting mold.

[0069] Although not specifically described in the above embodiment, resin molding may be performed with a release film provided on the surface of the molding die (for example, the lower surface of the upper die 120).

[0070] Furthermore, in the above embodiment, the molding die configured from the lower die 110 and the upper die 120 has been described as an example, but it is also possible to use a molding die including, for example, an intermediate die.

[0071] In the above embodiment, the dam portion 113 is fitted into the lead frame 2 by the first mold clamping, but it is also possible to fit the pilot pin 112 into the lead frame 2 by the first mold clamping. In addition, it is also possible to fit the lead frame 2 into other protrusions formed on the lower mold 110, not limited to the dam portion 113 and the pilot pin 112.

[0072] Furthermore, in the above embodiment, the mold clamping mechanism 140 that clamps the molds by moving (raising) the lower mold 110 has been exemplified, but the present invention is not limited to this, and any configuration may be used as long as the molds are clamped by relatively moving the lower mold 110 and the upper mold 120. For example, it is also possible to use a configuration in which the molds are clamped by moving (lowering) the upper mold 120, or a configuration in which the molds are clamped by moving both the lower mold 110 and the upper mold 120.

[0073] Furthermore, in the above embodiment, the mold clamping force when performing the first mold clamping is set to be smaller than the mold clamping force when performing the second mold clamping, but the mold clamping force when performing the first mold clamping may also be equal to the mold clamping force when performing the second mold clamping.

[0074] <Notes> A method for manufacturing a resin molded product according to a first aspect of the present disclosure is a method for manufacturing a resin molded product, which resin-moldes an object to be molded (lead frame 2) using a molding die including a lower die 110 having a protruding portion (dam portion 113) formed therein to be mated with the object to be molded, and an upper die 120 having a cavity (recess 121), the method comprising: a placing step (step S13) of placing the object to be molded on the lower die 110; a first clamping step (step S15) of clamping the lower die 110 and the upper die 120 relative to each other to mate with the object to be molded; a mold opening step (step S16) of opening the molds by moving the upper die 120 and the lower die 110 relative to each other; and a resin material supplying step (step S18) of supplying a resin material (resin tablet T) to a resin containing portion (pot 111) formed in the lower die 110 after the mold opening step. The method includes a second clamping step (step S20) of clamping the lower mold 110 and the upper mold 120 by moving them relative to each other, and a step (step S21) of resin molding the molding object by supplying the resin material supplied to the resin containing section to the cavity after the second clamping step. According to the method for manufacturing a resin molded product of the first aspect of the present disclosure, it is possible to improve the production efficiency of resin molded products. Specifically, the lead frame 2 can be set in the lower mold 110 without the lead frame 2 being sufficiently heated. This reduces the time required to preheat the lead frame 2, thereby reducing the cycle time of resin molding.

[0075] In the method for manufacturing a resin molded product having a second side surface according to the first side surface, the protruding portion includes at least one of a positioning portion (pilot pin 112) that positions the molding object relative to the lower mold 110, or a resin flow control portion (dam portion 113) that controls the flow of the resin material. According to the method for manufacturing a resin molded product having a second side surface according to the present disclosure, the lead frame 2 can be appropriately fitted to the dam portion 113 and the pilot pin 112.

[0076] In the method for manufacturing a resin molded product having a third side face according to the first or second side face, the mold clamping force in the first mold clamping step is lower than the mold clamping force in the second mold clamping step. According to the method for manufacturing a resin molded product having a third side face according to the present disclosure, the lead frame 2 is fitted into the dam portion 113 of the lower mold 110 with a relatively low mold clamping force, thereby reducing the power of the mold clamping mechanism 140.

[0077] In a fourth aspect of the method for manufacturing a resin molded product according to any one of the first to third aspects, the molding die is cleaned during the resin material supply step. According to the method for manufacturing a resin molded product according to the fourth aspect of the present disclosure, the quality of the resin molded product can be improved. Furthermore, cleaning the molding die can be performed efficiently by cleaning the molding die in conjunction with supplying the resin material.

[0078] In the method for manufacturing a resin molded product of a fifth aspect according to any one of the first to fourth aspects, the molding object is a lead frame 2. According to the method for manufacturing a resin molded product of the fifth aspect of the present disclosure, it is possible to improve production efficiency when resin molding the lead frame 2.

[0079] In the method for manufacturing a resin molded product according to the sixth aspect of the present disclosure, the lead frame 2 has a thickness of 0.5 mm or more. According to the method for manufacturing a resin molded product according to the sixth aspect of the present disclosure, the lead frame 2, which is relatively thick and difficult to heat sufficiently by preheating, can be properly set in the lower mold 110.

[0080] In the method for manufacturing a resin molded product of a seventh aspect according to the fifth or sixth aspect, the lead frame 2 is formed by stacking a plurality of frames. According to the method for manufacturing a resin molded product of the seventh aspect of the present disclosure, the lead frame 2, which is formed by stacking a plurality of frames and is difficult to heat sufficiently by preheating, can be properly set in the lower mold 110.

[0081] 1: Resin molding device, 2: Lead frame, 110: Lower mold, 111: Pot, 112: Pilot pin, 113: Dam portion, 120: Upper mold, 121: Recess

Claims

1. A method for manufacturing a resin molded product, in which an object to be molded is resin molded using a molding die equipped with a lower die having a protrusion formed therein to be mated with the object to be molded, and an upper die having a cavity, the method comprising: a placing step of placing the object to be molded on the lower die; a first clamping step of moving the lower die and the upper die relative to one another and clamping the die to fit the object to be molded with the protrusion; a die opening step of moving the upper die and the lower die relative to one another to open the die after the first clamping step; a resin material supplying step of supplying a resin material to a resin storage portion formed in the lower die after the die opening step; a second clamping step of moving the lower die and the upper die relative to one another and clamping the die; and a step of resin molding the object to be molded by supplying the resin material supplied to the resin storage portion to the cavity after the second clamping step.

2. A method for manufacturing a resin molded product as described in claim 1, wherein the protrusion includes at least one of a positioning portion that positions the molded object relative to the lower mold, or a resin flow control portion that controls the flow of the resin material.

3. A method for manufacturing a resin molded product according to claim 1 or 2, wherein the mold clamping force in the first mold clamping step is lower than the mold clamping force in the second mold clamping step.

4. The method for producing a resin molded product according to any one of claims 1 to 3, wherein the molding die is cleaned in the resin material supplying step.

5. The method for manufacturing a resin molded product according to any one of claims 1 to 4, wherein the molding object is a lead frame and has a thickness of 0.5 mm or more.

6. The method for manufacturing a resin molded product according to claim 5, wherein the lead frame is formed by stacking a plurality of frames.

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