JP7661285B2 - Mold, resin molding device, and method for manufacturing resin molded product - Google Patents

Description

The present invention relates to a molding die, a resin molding device, and a method for manufacturing a resin molded product.

Substrates with semiconductor chips fixed thereto are generally used as electronic components by being resin-sealed. Conventionally, resin molding devices for resin-sealing substrates and the like have been known that are equipped with transfer molding dies for manufacturing semiconductor packages such as molded array packaging (MAP) (see, for example, Patent Document 1).

In the molding die disclosed in Patent Document 1, when a transfer molding die is used to mold a highly fluid resin material, an air vent groove is closed using an air vent block. This prevents air from remaining in the cavity, causing the resin material to be left unfilled, and also prevents the resin material from leaking out of the die. In addition, as a measure against variations in the thickness of the board, an elastic member is used in the lower die cavity block and a floating pin is used in the upper die cavity block to give the cavity block a floating structure.

JP 2015-226014 A

In order to stably manufacture resin molded products, it is preferable that the pressing force acting on the substrate during resin molding is small. However, in the molding die disclosed in Patent Document 1, in order to prevent burrs, it is necessary to maximize the elastic force of the elastic member and the pressing force of the floating pin to suppress the floating of the lower and upper cavity blocks before flowing the resin material into the cavity. As a result, a large press is required for resin molding, and since excessive pressing force is applied to the substrate during resin molding, the air vent groove may be crushed and air may not be sufficiently discharged, remaining in the cavity and generating voids, or the cavity may not be filled entirely with resin material.

Therefore, there is a demand for a molding die, a resin molding device, and a method for manufacturing a resin molded product that can stably manufacture resin molded products by reducing the pressure acting on the substrate during resin molding.

The characteristic configuration of the molding mold of the present invention is that it comprises a lower mold including a lower mold cavity block on which an object to be molded is placed, and a pot block in which a pot into which the resin material is filled is formed, an upper mold including an upper mold cavity block having a cavity and an air vent groove, and a cull block arranged above the pot block and capable of rising and lowering independently of the upper mold cavity block, a first elastic member that presses the lower mold cavity block toward the upper mold, a plurality of support members that are elastically deformable and press the upper mold cavity block and the cull block, and a second elastic member that is capable of pressing the cull block to cause the cull block to protrude below the lower surface of the upper mold cavity block, and the elastic force of the second elastic member is set so that the second elastic member begins to elastically deform before the first elastic member when the mold is closed .

The resin molding device according to the present invention is characterized in that it includes the molding die described above and a clamping mechanism that clamps the molding die.

The method for manufacturing a resin molded product according to the present invention is characterized in that it is a method for manufacturing a resin molded product using the resin molding device described above, and includes a supply step of supplying the molding object and the resin material to the molding die, a mold clamping step of supplying the resin material filled in the pot to the cavity by elastically deforming the second elastic member with a first mold clamping force to bring the cull block and the pot block into contact and bringing the lower surface of the upper mold cavity block into contact with the upper surface of the molding object, and closing the air vent groove with a second mold clamping force, and a molding step of resin molding the molding object.

The present invention provides a molding die, a resin molding device, and a method for manufacturing a resin molded product that can stably manufacture a resin molded product by reducing the pressing force acting on a substrate during resin molding.

FIG. 2 is a schematic diagram illustrating a resin molding apparatus according to the present embodiment. FIG. 2 is a schematic diagram showing a mold clamping mechanism of the resin molding apparatus. FIG. 2 is a schematic diagram showing a molding process including a mold clamping process. 11 is a graph showing the relationship between molding time in a molding process, the position of a transfer mechanism, a mold clamping force, and a supply pressure of molten resin.

Below, an embodiment of the molding die, resin molding device, and method for manufacturing a resin molded product according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and various modifications are possible without departing from the gist of the present invention.

[Overall configuration of the device]
Molding objects such as substrates on which semiconductor chips (hereinafter sometimes simply referred to as "chips") are fixed are resin-sealed and used as electronic components. These electronic components are used, for example, as high-frequency module substrates for mobile communication terminals, power control module substrates, and device control substrates. One technique for resin-sealing molding objects is the transfer method, which resin-seals BGA (Ball Grid Array) substrates and the like to manufacture semiconductor packages. In this transfer method, a substrate on which a chip is fixed is placed in a cavity of a molding die, a resin tablet made of solidified powdered resin is supplied to the pot of the molding die and heated and melted, and then, with the molding die clamped, the molten resin made by melting the resin tablet is supplied to the cavity and hardened, and the die is opened to manufacture a resin molded product.

The powdered resin includes not only powdered resin, but also resin tablets formed of solid resin compressed from powdered resin, both of which melt when heated to become liquid molten resin. This powdered resin may be a thermoplastic resin or a thermosetting resin. Thermosetting resins reduce in viscosity when heated, and when further heated, polymerize and harden to become a hardened resin. The powdered resin in this embodiment is preferably a resin tablet formed from a solid resin for ease of handling, and is preferably a highly fluid thermosetting resin containing finely divided fillers to ensure that the molten resin is filled between the chip and the substrate.

Figure 1 shows a schematic configuration of a resin molding apparatus 100 according to this embodiment. The resin molding apparatus 100 is an apparatus that molds a pre-molding substrate Sa (an example of a molding target) with resin using a molding die C. In this embodiment, the pre-molding substrate Sa is rectangular, and a semiconductor chip is fixed to it in advance.

The resin molding apparatus 100 includes a CPU 1 as a central control device, a memory unit 8 that stores control information such as control programs, a molding mechanism 2 having a molding die C, a drive mechanism that drives each part described below, and a touch panel 9 that receives operation commands and abnormality processing related information input from a user and displays various output information of the resin molding apparatus 100. The CPU 1 constitutes a control unit 10 that controls the operation of each part of the resin molding apparatus 100 by executing programs stored in the memory unit 8, etc.

Unless otherwise specified, the operation of the resin molding device 100 described below is performed based on the operational commands of the control unit 10. In the following explanation, the operational commands of the control unit 10 will be omitted as a general rule, and the operational commands of the control unit 10 will be explained as necessary.

The resin molding device 100 is configured by connecting the following modules as an integrated device in this order: a supply module M1 having an in-magazine 7 that stores a plurality of pre-resin-molded substrates Sa; a molding module M2 having a molding die C; and a storage module M3 having an out-magazine 72 that stores resin-molded substrates Sb (an example of a resin molded product) after the pre-resin-molded substrates Sa have been molded with resin. The supply module M1, molding module M2, and storage module M3 are provided with guides G that are arranged in a straight line across each of these modules. The guides G are rail-shaped members that allow the loader 40 and unloader 44, described below, to travel. The guides G are arranged on the rear side of each of the modules.

Each module is detachable from the others and can be increased or decreased. In this embodiment, the resin molding device 100 has two molding modules M2. The resin molding device 100 may have only one molding module M2 or three or more.

[Drive mechanism]
The drive mechanism includes a loader 40, a substrate supply unit 42, an unloader 44, a mold clamping mechanism 35, and a transfer mechanism 39 (see FIG. 2) which will be described later.

The loader 40 is a transport mechanism that transports the pre-resin-molded substrate Sa into the mold C. The substrate supply unit 42 is a transport mechanism that pushes out the pre-resin-molded substrate Sa from the in-magazine 7 and passes it to the alignment mechanism 70. The unloader 44 is a transport mechanism that transports the resin-molded substrate Sb from the mold C. The transfer mechanism is a mechanism that supplies molten resin in the form of a resin tablet T (an example of a resin material) from a pot to the cavity in the mold C. The mold clamping mechanism 35 is a mechanism that clamps the mold C. The transfer mechanism 39 is driven independently of the mold clamping mechanism 35.

The loader 40, the substrate supply unit 42, and the unloader 44 each have an actuator 40b, an actuator 42b, and an actuator 44b. The actuators 40b, 42b, and 44b are air cylinders that correspond to their respective installation locations and the distances to which each part is driven.

[Substrate supply unit]
The substrate supply unit 42 is a mechanism for pushing out the pre-resin molding substrates Sa one by one from the in-magazine 7, which is a storage container that stores a plurality of pre-resin molding substrates Sa at intervals in the vertical direction, and transporting them to the alignment mechanism 70. The substrate supply unit 42 has an actuator 42b. In this embodiment, the substrate supply unit 42 pushes out the pre-resin molding substrates Sa from the in-magazine 7 by the actuator 42b, and moves them to the alignment mechanism 70 arranged adjacent to the in-magazine 7. The alignment mechanism 70 has a rotating disk 70a, and when the pre-resin molding substrates Sa are placed, the alignment mechanism 70 rotates the rotating disk 70a to align the pre-resin molding substrates Sa so that they are in a state suitable for picking up the pre-resin molding substrates Sa by the loader 40. The substrate supply unit 42, the in-magazine 7, and the alignment mechanism 70 are provided in the supply module M1. The substrate supply unit 42, the in-magazine 7, and the alignment mechanism 70 are arranged on the front side of the guide G in the supply module M1.

〔loader〕
The loader 40 is a transport mechanism that carries the resin pre-molding substrate Sa into the molding die C. The loader 40 is movable from the supply module M1 to the molding module M2 along a guide G. The loader 40 has a loader pickup unit 40a that picks up the resin pre-molding substrate Sa and the resin tablet T.

The loader pickup unit 40a has multiple pairs of claws (not shown) that extend downward. The loader pickup unit 40a drives the pair of claws with an actuator (not shown) to pick up the pre-resin molding substrate Sa from the alignment mechanism 70, transport it to above the lower mold LM of the molding die C, and place (carry) it on the lower mold LM. Hereinafter, the pick-up operation by the loader pickup unit 40a will be simply referred to as picking up.

The loader pickup unit 40a also drives the claws for holding the resin material by another actuator (not shown) to pick up the resin tablet T from the resin supply device 79. The resin tablet T is picked up in the same manner as the pre-resin molding substrate Sa is picked up. However, in this embodiment, one resin tablet T is picked up per claw.

The loader pickup unit 40a can be moved forward and backward from the rear side to the front side in FIG. 1 by the actuator 40b. The loader 40 moves the loader pickup unit 40a forward and backward to pick up a resin pre-molded substrate Sa from the alignment mechanism 70, move from the supply module M1 to the molding module M2, and transfer the resin pre-molded substrate Sa to the molding die C. The loader 40 also moves the loader pickup unit 40a forward and backward to pick up a resin tablet T from the resin supply device 79, move from the supply module M1 to the molding module M2, and transfer the resin tablet T to the molding die C.

[Unloader]
The unloader 44 is a transport mechanism that transports the resin-molded substrate Sb out of the molding die C. The unloader 44 can move along the guide G from the molding module M2 to the storage module M3. The unloader 44 has an unloader pickup section 44a that picks up the resin-molded substrate Sb and the like. The unloader pickup section 44a can advance and retreat from the rear side to the front side in FIG. 1 by an actuator 44b. The unloader 44 moves the unloader pickup section 44a forward and backward to pick up the resin-molded substrate Sb from the lower die LM of the molding die C, moves from the molding module M2 to the storage module M3, and transports the resin-molded substrate Sb into the gate break mechanism 71 of the storage module M3. The unloader 44 transports the resin-molded substrate Sb, from which the unnecessary resin portion has been removed by the gate break mechanism 71, to the out-magazine 72 and stores it therein.

The unloader pickup unit 44a has multiple pairs of claws (not shown) that extend downward, similar to the loader pickup unit 40a. Pickup by the unloader pickup unit 44a is performed in the same manner as pickup by the loader pickup unit 40a.

Next, we will explain the molding module M2 in detail.

2, the molding module M2 has tie bars 32 erected at the four corners of a lower fixed platen 31 having a rectangular shape in plan view, and an upper fixed platen 33 having a rectangular shape in plan view is provided near the upper end of the tie bars 32. A movable platen 34 having a rectangular shape in plan view is provided between the lower fixed platen 31 and the upper fixed platen 33. The movable platen 34 has holes through which the tie bars 32 pass at the four corners, and can move up and down along the tie bars 32. A clamping mechanism 35, which is a device for moving the movable platen 34 up and down, is provided on the lower fixed platen 31. This clamping mechanism 35 includes an electric motor Ma consisting of a servo motor or the like as a driving source, and a load sensor Wa consisting of a strain gauge, a load cell, or the like for measuring the clamping force (hereinafter referred to as the "clamping force") of the mold C. The clamping mechanism 35 clamps the mold C by moving the movable platen 34 upward, and opens the mold C by moving the movable platen 34 downward.

The molding die C is composed of a lower die LM and an upper die UM. The lower die LM and the upper die UM are composed of metal dies etc. that are arranged opposite each other.

The lower mold LM is placed on the lower mold plate 38 placed on the movable platen 34. The lower mold LM includes a base block 51, a side block 52 and a lower mold cavity block 53 placed on the base block 51, and a pot block 54. The side block 52 is attached to the base block 51. A first elastic member 55 is disposed between the base block 51 and the lower mold cavity block 53, and the first elastic member 55 presses the lower mold cavity block 53 toward the upper side where the upper mold UM is located relative to the base block 51. An example of the first elastic member 55 is a stack of multiple disc springs. The lower mold cavity block 53 is configured to be movable in the vertical direction relative to the base block 51 and the side block 52 by the elastic deformation of the first elastic member 55. That is, the lower mold LM has a floating structure in which the lower mold cavity block 53 can move in the vertical direction. The elastic force of the first elastic member 55 is set so that it begins to elastically deform before the floating pin 63, which will be described later, when the mold is closed.

Before the mold C is clamped, the upper surface of the lower cavity block 53 and the upper surface 58 of the side block 52 are flush with each other in the lower mold LM. The resin pre-molding substrate Sa is placed on the upper surface of the lower cavity block 53 with the surface on which the semiconductor chip Sc and the like are fixed facing up. The lower cavity block 53 also has a lower heater 36 built in to heat the resin pre-molding substrate Sa and the resin tablet T. In this embodiment, the lower mold LM has two lower cavity blocks 53, 53, and the pot block 54 is disposed at a position sandwiched between the two lower cavity blocks 53, 53. The pot block 54 is formed with a cylindrical recessed pot 54b, and the pot 54b is filled with a resin tablet T (resin that melts when heated). A plunger 54a driven by an electric motor Mb such as a servo motor is inserted below the pot block 54 so as to be movable up and down. An elastic member (not shown) is provided at the support portion of the plunger 54a, and the plunger 54a is slightly displaced by the elastic force of the elastic member to release excessive pressure and to adapt to variations in the amount of resin when the resin tablet T is melted during pressure retention. The lower mold LM also has a load sensor Wb consisting of a strain gauge, load cell, etc., for measuring the force with which the plunger 54a pushes out the molten resin Ta (an example of a resin material).

The upper mold UM is disposed opposite the lower mold LM. The upper mold UM has a holder base 61 fixed to the lower surface of the upper fixed platen 33, a pin holder 62 fixed to the lower surface of the holder base 61, an upper mold cavity block 64 supported by the pin holder 62 via a plurality of floating pins 63 (an example of a support member) and a cull block 65. The floating pins 63 are inserted into a plurality of through holes formed in the pin holder 62, and the upper and lower ends are not fixed to the holder base 61, the upper mold cavity block 64, or the cull block 65. The length of the floating pin 63 disposed above the cull block 65 is the same as the length of the floating pin 63 disposed above the upper mold cavity block 64. As described below, the cull block 65 is further supported by the holder base 61 via a second elastic member 66 so that its lower surface 69 protrudes downwardly below the lower surface 68 of the upper cavity block 64, so that the other end of the floating pin 63 arranged on the cull block 65, which is held by the pin holder 62, is spaced apart from the holder base 61. Before the mold C is clamped, the upper cavity block 64 and the cull block 65 are spaced apart from the pin holder 62.

A cavity MC, which is a recess into which molten resin Ta is supplied, is formed on the lower surface 68 of the upper cavity block 64, and an upper heater 37 for heating the cavity MC is built into the upper cavity block 64. The upper cavity block 64 faces the lower cavity block 53 and the side block 52.

In this embodiment, the upper mold UM has two upper mold cavity blocks 64, 64, and the cull block 65 is arranged at a position sandwiched between the two upper mold cavity blocks 64, 64. The cull block 65 has a runner 65a that causes the molten resin Ta to flow from the pot 54b of the pot block 54 toward the cavity MC. That is, the cull block 65 is arranged above the pot block 54. The upper mold cavity block 64 and the cull block 65 are made of separate members, and the cull block 65 is configured to be able to rise and fall (move up and down) independently of the upper mold cavity block 64. The cull block 65 is provided with a gate 65b, which is an entrance through which the molten resin Ta flows from the runner 65a into the cavity MC. The cull block 65 is supported by the holder base 61 via a second elastic member 66, one end of which is fixed to the holder base 61. Before the mold C is clamped, the cull block 65 is configured such that the lower surface 69 of the cull block 65 protrudes downward from the lower surface 68 of the upper mold cavity block 64 due to the second elastic member 66. An example of the second elastic member 66 is a stack of multiple disc springs. The elastic force of the second elastic member 66 is set so that it begins to elastically deform before the first elastic member 55 when the mold is clamped.

An air vent groove 64a that exhausts air from the cavity MC to the outside of the upper mold UM is formed on the lower surface 68 of the upper mold cavity block 64 and at a location away from the gate 65b. The air vent groove 64a is configured to be opened and closed by an air vent block 67. One end of the air vent block 67 is attached to the pin holder 62, and is inserted into a through hole formed in the upper mold cavity block 64 so that it is located midway through the air vent groove 64a when moving forward. The lower end of the air vent block 67 is set to be higher than the lower surface 68 of the upper mold cavity block 64 before the molding die C is clamped. That is, when the air vent block 67 is flush with or above the bottom surface of the air vent groove 64a with the mold C clamped, the air inside the cavity MC can be discharged to the outside of the upper mold UM by operating a pump (not shown), and when the air vent block 67 advances (moves downward) to close the air vent groove 64a, the air (and molten resin Ta) in the cavity MC cannot be discharged to the outside of the upper mold UM. Since one end of the air vent block 67 according to this embodiment is attached to the pin holder 62, when the floating pin 63 is compressed by clamping the mold with the clamping mechanism 35, the air vent block 67 can be moved forward (downward) relative to the upper mold cavity block 64. Therefore, a special drive mechanism for moving the air vent block 67 forward and backward is not required, and the mold C can be simplified in configuration and inexpensively constructed.

[Method for manufacturing resin molded products]
Next, a method for manufacturing a resin molded product will be described with reference to Figures 1 to 4. The method for manufacturing a resin molded product (resin-molded substrate Sb) includes a supply step of supplying a pre-resin-molded substrate Sa and a resin tablet T to a mold C, a clamping step of clamping the mold C, and a molding step of resin-molding the pre-resin-molded substrate Sa by filling the cavity MC with molten resin Ta supplied from the gate 65b. This molding step is a step in which the molding module M2 resin-moldes the pre-resin-molded substrate Sa during the period from when the pre-resin-molded substrate Sa is carried into the molding module M2 until when the resin-molded substrate Sb is carried out from the molding module M2, and this molding step includes a clamping step. The operation of the mold C and the clamping mechanism 35 in the molding step is controlled by the control unit 10.

First, the supply process will be described. As shown in FIG. 1, the loader 40 is preheated with the resin tablet T storage space insulated. In addition, the heaters 36 and 37 are energized to preheat the mold C (see also FIG. 2). Then, a plurality of resin pre-molding substrates Sa taken out from the in-magazine 7 are placed on the alignment mechanism 70. The alignment mechanism 70 has a rotating disk 70a, and when the resin pre-molding substrates Sa are placed, the alignment mechanism 70 rotates the rotating disk 70a to align the resin pre-molding substrates Sa so that they are in a state suitable for the loader 40 to pick up the resin pre-molding substrates Sa. The loader pickup unit 40a picks up the resin pre-molding substrates Sa from the alignment mechanism 70 by the actuator 40b and places them on the loader 40, and also picks up the resin tablet T from the resin supply device 79 and stores it in the storage space for the resin tablet T of the loader 40. Then, the loader 40 transports the resin pre-molded substrate Sa to the molding module M2, places the resin pre-molded substrate Sa with the side on which the semiconductor chip Sc is fixed facing upward on the substrate set section of the lower mold LM, and places the resin tablet T in the pot 54b of the pot block 54 (see FIG. 2). By placing the resin tablet T in the pot 54b of the pot block 54, the lower mold heater 36 built into the lower mold LM heats the resin tablet T to become molten resin Ta. Note that before the movable platen 34 is raised by the mold clamping mechanism 35 described later, a release film (not shown) is attached to the lower surface 68 of the upper mold cavity block 64 of the upper mold UM.

Next, the molding process including the mold clamping process will be described. First, from the state shown in FIG. 2, the movable platen 34 is moved upward by the mold clamping mechanism 35 to move the lower mold LM relatively toward the upper mold UM, and the pot block 54 and the cull block 65 are brought into contact as shown in FIG. 3(A). At this point, the upper surface 56 of the pre-resin molding substrate Sa placed on the lower mold LM is not in contact with the lower surface 68 of the upper mold cavity block 64.

Figure 4 shows graph (A) with the molding time for producing a resin molded product on the horizontal axis and the position of the transfer mechanism on the vertical axis, graph (B) with the molding time on the horizontal axis and the clamping force on the vertical axis, and graph (C) with the molding time on the horizontal axis and the supply pressure of molten resin Ta to the cavity MC on the vertical axis. That is, the items on the horizontal axis of graphs (A), (B), and (C) in Figure 4 are common, but the items on the vertical axis are different. The position of the transfer mechanism is set to zero (reference position) in the state of Figure 3 (A). The state shown in Figure 3 (A) is shown at time (a) in graphs (A), (B), and (C) in Figure 4. That is, at time (a), it can be seen from graph (A) that the transfer mechanism has not moved upward from the reference position, from graph (B) that the clamping force due to the elastic force of the second elastic member 66 has not yet been generated, and from graph (C) that the supply of molten resin Ta has not yet started, so the supply pressure is zero. Hereinafter, the mold clamping state in FIG. 3(A) will be referred to as the first mold clamping state. Note that each of the times (a) to (e) shown in FIG. 4 (timing) is preset by the control unit.

After the time (a) has elapsed, when the movable platen is further moved upward from the first mold clamping state by the mold clamping mechanism to relatively move the lower mold LM toward the upper mold UM, the second elastic member 66 begins to elastically deform, and a mold clamping force (hereinafter referred to as the "first mold clamping force") is generated as shown in graph (B) of FIG. 4. Then, as shown in FIG. 3(B), the second elastic member 66 elastically deforms while the pot block 54 and the cull block 65 are in close contact, and the upper surface 56 of the pre-molded resin substrate Sa comes into contact with the lower surface 68 of the upper mold cavity block 64. At this time, the first elastic member 55 and the floating pin 63 do not exert any elastic force on the pre-molded resin substrate Sa and the upper mold cavity block 64, or exert only a very small elastic force on them. Therefore, the pressing force acting on the pre-molded resin substrate Sa by the first elastic member 55 and the floating pin 63 is extremely small. Therefore, the upper surface of the lower cavity block 53 and the upper surface 58 of the side block 52 are maintained flush with each other. Hereinafter, the mold clamping state in FIG. 3(B) will be referred to as the second mold clamping state. Note that FIG. 3(B) shows the state in which the molten resin Ta is being supplied with the positional relationship between the lower mold LM and the upper mold UM as described above.

In the second mold clamping state, the air in the cavity MC is discharged from the air vent groove 64a to the outside of the upper mold UM by a pump (not shown), and the plunger 54a is moved upward by the electric motor Mb to flow the molten resin Ta from the pot 54b through the runner 65a of the cull block 65 to the gate 65b. This starts the supply of the molten resin Ta to the cavity MC. The start of this supply is indicated by time (b) in graphs (A), (B), and (C) of FIG. 4. That is, at time (b), the transfer mechanism including the plunger 54a starts moving upward from graph (A), the first mold clamping force after time (a) is maintained from graph (B), and the supply of the molten resin Ta has started and a supply pressure is generated from graph (C), but the pressure is very small. As a result, even if the pressing force acting on the pre-resin molding substrate Sa is small, there is no risk of the molten resin Ta leaking out of the molding mold C.

After time (b) has elapsed in graphs (A), (B), and (C) of FIG. 4, the transfer mechanism including the plunger rises while maintaining the second state (see graph (A) of FIG. 4), and the molten resin Ta in the pot 54b is filled into the cavity MC. At this time, the first clamping force is maintained as shown in graph (B) of FIG. 4, and the supply pressure of the molten resin Ta is maintained at a minute state as shown in graph (C) of FIG. 4. Then, at time (c) just before the molten resin Ta has completely filled the cavity MC and no resin leakage to the outside of the mold C has occurred, the mold clamping mechanism moves the movable platen further upward to increase the clamping force (see graph (B) of FIG. 4). As a result, the first elastic member 55 is elastically deformed, and as shown in FIG. 3C, the side block 52 of the lower mold LM and the upper mold cavity block 64 of the upper mold UM come into contact with each other, and the upper surface 56 of the pre-resin molding substrate Sa becomes flush with the upper surface 58 of the side block 52 and the upper surface 57 of the pot block 54. After the compression amount (elastic deformation amount) due to the elastic deformation of the first elastic member 55 becomes maximum, the floating pin 63 is elastically deformed, and when the compression amount becomes maximum, the pin holder 62 comes into contact with the upper mold cavity block 64. As a result, as shown in FIG. 3C, the air vent block 67 closes the air vent groove 64a. As a result, the air in the cavity MC cannot be discharged to the outside, but since the cavity MC is almost filled with the molten resin Ta and almost no air remains, there is no risk of voids being generated after the molten resin Ta hardens. Hereinafter, the mold clamping state at this time is referred to as the third mold clamping state, and the mold clamping force is referred to as the second mold clamping force. Note that the compression caused by the elastic deformation of the floating pin 63 is exaggerated in Figures 3(B) and 3(C). The actual amount of compression of the floating pin 63 is small.

After the time (c) in the graphs (A), (B), and (C) of FIG. 4 has elapsed, the transfer mechanism including the plunger rises, and the molten resin Ta is supplied into the cavity MC, and at time (d), the plunger 54a reaches the top dead center. After the time (d) has elapsed, the plunger 54a does not move, but as shown in the graph (A) of FIG. 4, the transfer mechanism continues to rise. This is because the elastic member (not shown) provided on the support part of the plunger 54a elastically deforms. As a result, the molten resin Ta remaining in the pot 54b is filled into the cavity MC, and since the air vent groove 64a is closed, the supply pressure of the molten resin Ta rises sharply (see graph (C) of FIG. 4). Then, when the supply pressure of the molten resin Ta reaches a predetermined value, the transfer mechanism stops (see time (e) in the graphs (A) and (C) of FIG. 4). This ends the supply of the molten resin Ta. As shown in graph (B) of Figure 4, the third mold clamping state and the second mold clamping force are maintained from time (c) onwards.

As shown in graphs (A), (B), and (C) of FIG. 4, after time (e) has elapsed, the position of the transfer mechanism, the clamping force, and the supply pressure of the molten resin are maintained, and the molten resin Ta is hardened. After a predetermined time has elapsed, the control unit 10 reduces the clamping force of the clamping mechanism to move the movable platen downward and open the molding die C. Then, the resin-molded substrate Sb is released from the cavity MC to complete the resin molding. After that, the resin-molded substrate Sb is picked up by the unloader pickup unit 44a of the unloader 44, and the unloader 44 moves the resin-molded substrate Sb from the molding module M2 to the storage module M3. Then, the gate break mechanism 71 removes unnecessary resin from the resin-molded substrate Sb, and the substrate is stored in the out-magazine 72 (see FIG. 1).

In this embodiment, the second elastic member 66 is elastically deformed to bring the upper surface 56 of the pre-molded resin substrate Sa into contact with the lower surface 68 of the upper cavity block 64, and the first elastic member 55 and the floating pin 63 start and perform resin supply in a state where they exert no elastic force or only a very small elastic force on the pre-molded resin substrate Sa and the upper cavity block 64. In the conventional device, it is necessary to elastically deform the first elastic member 55 of the lower mold to bring the upper surface 56 of the pre-molded resin substrate Sa into contact with the lower surface 68 of the upper cavity block 64 to perform resin supply, and a large clamping force (pressing force) that is large enough to elastically deform the first elastic member 55 is applied to the pre-molded resin substrate during resin injection. In this embodiment, the second elastic member 66 is set to start elastic deformation before the first elastic member 55, that is, the elastic coefficient of the second elastic member 66 is set to be smaller than the elastic coefficient of the first elastic member 55, so that the pressing force acting on the substrate during resin molding can be reduced.

Furthermore, in this embodiment, the first elastic member 55 and the floating pin 63 are elastically deformed just before the filling of the molten resin Ta into the cavity MC is completed, and first the upper surface 56 of the pre-resin molding substrate Sa is flush with the upper surface 58 of the side block 52 and the upper surface 57 of the pot block 54, and then immediately thereafter the floating pin 63 is completely elastically deformed and the air vent groove 64a is closed by the air vent block 67. In conventional devices, it was necessary to set the elastic force at which the floating pin 63 begins to elastically deform to be significantly greater than the elastic force at which the first elastic member 55 elastically deforms so that the air vent groove is not closed until just before the filling of the molten resin Ta into the cavity MC is completed. In this embodiment, resin can be filled into most of the cavity MC with a smaller clamping force (in this embodiment, the first clamping force) than in the past, so there is no need to set the elastic force at which the floating pin 63 starts to elastically deform so as not to close the air vent groove 64a, as in the past, and the final clamping force (in this embodiment, the second clamping force) can also be set smaller than in the past. As a result, the pressing force acting on the substrate during resin molding can be reduced.

[Another embodiment]
Hereinafter, an embodiment different from the embodiment described above will be described. Note that, for ease of understanding, the same terms and reference numerals will be used for the same members as those in the embodiment described above.

<1> In the above-described embodiment, the powdered resin of the resin tablet T is a highly fluid thermosetting resin containing a filler, but it does not have to be highly fluid. In addition, it does not have to contain a filler.

<2> In the above-described embodiment, the first elastic member 55 and the second elastic member 66 are both stacked disc springs, but this is not limited to this. Any elastic member can be used, such as a compression coil spring.

<3> In the above-described embodiment, the pre-resin molding substrate Sa was rectangular, but this is not limited to this. For example, a substrate of any shape, such as a circular substrate, can be used. The size of the substrate is also not limited.

If the size of the resin pre-molded substrate Sa becomes larger, the cavity MC of the upper mold cavity block 64 becomes larger, and the area of the upper mold cavity block 64 other than the cavity MC that contacts the upper surface 56 of the resin pre-molded substrate Sa becomes relatively smaller. In this case, the pressure acting on the upper surface 56 of the resin pre-molded substrate Sa due to the mold clamping force becomes larger compared to the case where an upper mold cavity block 64 with a smaller cavity MC is used. However, with the resin molding device 100 using the molding mold C according to this embodiment, the mold clamping force when supplying the molten resin Ta can be the first mold clamping force in which only the second elastic member 66 exerts elastic force, so that even if the size of the resin pre-molded substrate Sa is large, excessive pressing force can be prevented from acting on the resin pre-molded substrate Sa.

<4> In the above-described embodiment, the time (c) (time elapsed from time (b)), which is the time (timing) at which the clamping force shown in graph (B) of FIG. 4 is changed from the first clamping force to the second clamping force, was set in advance by the control unit 10, but this is not limited to this. For example, the clamping force may be controlled to be changed based on the resin pressure of the molten resin Ta measured by the load sensor Wb. In addition, the clamping force may be controlled to be changed based on the position of the transfer mechanism 39 (position of the plunger 54a) shown in graph (A) of FIG. 4.

<5> In the above-described embodiment, the cull block 65 is arranged only in the upper mold UM, but this is not limited to this. The cull block may be arranged separately in the upper mold UM and the lower mold LM.

[Summary of the above embodiment]
An outline of the molding die C, the resin molding apparatus 100, and the method for producing the resin molded product (resin molded substrate Sb) described in the above embodiment will be described below.

(1) The characteristic configuration of the molding die C is that it includes a lower die LM including a lower die cavity block 53 on which the molding object (pre-molded resin substrate Sa) is placed, and a pot block 54 in which a pot 54b is formed in which a resin material (resin tablet T, molten resin Ta) is filled, an upper die UM including an upper die cavity block 64 having a cavity MC and an air vent groove 64a, and a cull block 65 that is arranged above the pot block 54 and can be raised and lowered independently of the upper die cavity block 64, a first elastic member 55 that presses the lower die cavity block 53 toward the upper die UM, a plurality of support members (floating pins 63) that press the upper die cavity block 64 and the cull block 65 and are elastically deformable, and a second elastic member 66 that can press the cull block 65 to cause the cull block 65 to protrude below the lower surface of the upper die cavity block 64.

In the molding die C according to this characteristic configuration, before the die is closed, that is, before the die is closed, the second elastic member 66 presses the cull block 65 so that the cull block 65 protrudes downward from the lower surface 68 of the upper die cavity block 64. As a result, when the die is closed, the cull block 65 contacts the pot block 54 of the lower die LM before the upper die cavity block 64. After this, the deformation of the second elastic member 66 causes the upper die cavity block 64 and the upper surface 56 of the object to be molded (substrate Sa before resin molding) to come into contact, so that the resin material (molten resin Ta) can be supplied to the cavity MC, and it is possible to prevent excessive pressing force from acting on the object to be molded (substrate Sa before resin molding) when the die is closed (when molding resin).

(2) In the molding die C described in (1) above, the elastic force of the first elastic member 55 may be set so that the first elastic member 55 begins to elastically deform before the multiple support members (floating pins 63) when the die is closed.

With this configuration, the molding object (pre-molded resin substrate Sa) is held by the elastic force of the first elastic member 55, which prevents excessive pressure from acting on the molding object (pre-molded resin substrate Sa) when the mold is closed (during resin molding).

(3) In the molding die C described in (1) or (2) above, the elastic force of the second elastic member 66 may be set so that the second elastic member 66 begins to elastically deform before the first elastic member 55 when the die is closed.

With this configuration, the molding object (pre-molded resin substrate Sa) is held by the elastic force of the second elastic member 66, which prevents excessive pressure from being applied to the molding object (pre-molded resin substrate Sa) when the mold is closed (during resin molding).

(4) The resin molding device 100 is characterized in that it includes a molding die C described in any one of (1) to (3) above, and a clamping mechanism 35 that clamps the molding die C.

The resin molding device 100 according to this characteristic configuration can manufacture a resin molded product (resin molded substrate Sb) using the mold C described in any one of (1) to (3) above.

(5) The manufacturing method of a resin molded product (resin molded substrate Sb) using the resin molding apparatus 100 described in (4) above is characterized in that it includes a supply step of supplying the molding object (resin pre-molding substrate Sa) and resin material (resin tablet T) to the molding mold C, a mold clamping step of elastically deforming the second elastic member 66 by the first mold clamping force to bring the cull block 65 and the pot block 54 into contact and bringing the lower surface 68 of the upper mold cavity block 64 into contact with the upper surface 56 of the molding object (resin pre-molding substrate Sa) to supply the resin material (resin tablet T, molten resin Ta) filled in the pot 54b to the cavity MC, and closing the air vent groove 64a by the second mold clamping force, and a molding step of resin molding the molding object (resin pre-molding substrate Sa).

In the manufacturing method of a resin molded product (resin-molded substrate Sb) having this characteristic, the mold C is supplied with the object to be molded (substrate Sa before resin molding) and resin material (resin tablet T) in the supply step, and then the cull block 65 and pot block 54 are brought into contact with each other by a first mold clamping force that elastically deforms the second elastic member 66 in the mold clamping step, and the lower surface 68 of the upper mold cavity block 64 is brought into contact with the upper surface 56 of the object to be molded (substrate Sa before resin molding). Then, in this state, resin material (molten resin Ta) is supplied to the cavity MC, and then the air vent groove 64a is closed by a second mold clamping force to manufacture the mold-clamped resin molded product (resin-molded substrate Sb) (molding step). In this way, the resin material (molten resin Ta) is supplied with the first mold clamping force until the air vent groove 64a is closed with the second mold clamping force to produce a resin molded product (resin molded substrate Sb), so that the resin molded product (resin molded substrate Sb) can be produced without applying excessive pressure to the object to be molded (pre-resin molded substrate Sa).

This also allows the second clamping force to be significantly smaller than the clamping force in the second clamping step of the resin sealing device disclosed in Patent Document 1, making it possible to miniaturize the press machine that performs the clamping. Furthermore, the pressing force acting on the air vent groove 64a that contacts the upper surface 56 of the molding object (pre-resin molding substrate Sa) can also be reduced, preventing the air vent groove 64a from being crushed.

(6) In the manufacturing method of the resin molded product (resin molded substrate Sb) described in (5) above, in the mold clamping process, the elastic force of the second elastic member 66 may be used to bring the cull block 65 and the pot block 54 into contact with each other, and then the second elastic member 66 may be compressed to bring the lower surface 68 of the upper mold cavity block 64 into contact with the upper surface 56 of the object to be molded (pre-resin molded substrate Sa).

With this method, the cull block 65 and pot block 54 come into contact due to the elastic deformation of the second elastic member 66, and the lower surface 68 of the upper die cavity block 64 comes into contact with the upper surface 56 of the object to be molded (pre-molded resin substrate Sa), so that a resin molded product (pre-molded resin substrate Sb) can be manufactured without applying excessive pressure to the object to be molded (pre-molded resin substrate Sa).

(7) In the manufacturing method of the resin molded product (resin molded substrate Sb) described in (5) or (6) above, the air vent groove 64a may be closed in the mold clamping process when the compression amount of the support member (floating pin 63) becomes maximum due to the second mold clamping force.

Normally, air is discharged from the air vent groove 64a in the cavity MC, so the air vent groove 64a is not closed until just before the cavity MC is filled with the resin material (molten resin Ta). Therefore, with this method, the air vent groove 64a is closed when the compression amount of the support member (floating pin 63) is maximized by the second mold clamping force, so that a resin molded product (resin molded substrate Sb) can be manufactured without applying a pressing force from the second mold clamping force to the molded object (pre-resin molded substrate Sa) until just before the resin material (molten resin Ta) is filled.

(8) In the manufacturing method of a resin molded product (resin molded substrate Sb) described in any one of (5) to (7) above, when the amount of elastic deformation of the first elastic member 55 is maximized, the upper surface 56 of the molding object (pre-resin molded substrate Sa) and the upper surface 57 of the pot block 54 may be flush with each other.

With this method, the timing at which the pressing force due to the elastic force of the first elastic member 55 acts on the molding object (the substrate Sa before resin molding) can be delayed, thereby shortening the time during which the pressing force acts on the molding object (the substrate Sa before resin molding).

The present invention can be used in molding dies, resin molding devices, and methods for manufacturing resin molded products.

35: Mold clamping mechanism 53: Lower mold cavity block 54: Pot block 54b: Pot 55: First elastic member 63: Floating pin (support member)
64: Upper mold cavity block 64a: Air vent groove 65: Cull block 66: Second elastic member 100: Resin molding device C: Molding mold LM: Lower mold MC: Cavity Sa: Substrate before resin molding (molding object)
Sb: Resin molded substrate (resin molded product)
T: Resin tablet (resin material)
Ta: Molten resin (resin material)
UM: Upper type

Claims (8)

a lower mold including a lower mold cavity block on which an object to be molded is placed and a pot block in which a pot to be filled with a resin material is formed;
an upper mold including an upper mold cavity block having a cavity and an air vent groove, and a cull block arranged above the pot block and capable of being raised and lowered independently of the upper mold cavity block;
a first elastic member that presses the lower die cavity block toward the upper die;
a plurality of elastically deformable support members that press the upper die cavity block and the cull block;
a second elastic member capable of pressing the cull block to cause the cull block to protrude below a lower surface of the upper die cavity block ,
The molding die has an elastic force set so that, when the die is closed, the second elastic member begins to elastically deform before the first elastic member does . The mold according to claim 1, wherein the elastic force of the first elastic member is set so that the first elastic member starts to elastically deform before the multiple support members when the mold is closed. The mold according to claim 1 or 2,
and a mold clamping mechanism that clamps the molding die. A method for manufacturing a resin molded product using a resin molding device,
The resin molding apparatus includes a molding die and a clamping mechanism that clamps the molding die,
The mold is
a lower mold including a lower mold cavity block on which an object to be molded is placed and a pot block in which a pot to be filled with a resin material is formed;
an upper mold including an upper mold cavity block having a cavity and an air vent groove, and a cull block arranged above the pot block and capable of being raised and lowered independently of the upper mold cavity block;
a first elastic member that presses the lower die cavity block toward the upper die;
a plurality of elastically deformable support members that press the upper die cavity block and the cull block;
a second elastic member capable of pressing the cull block to cause the cull block to protrude below a lower surface of the upper die cavity block,
a supplying step of supplying the molding object and the resin material to the molding die;
a mold clamping step in which the second elastic member is elastically deformed by a first mold clamping force to bring the cull block and the pot block into contact with each other and also bring the lower surface of the upper mold cavity block into contact with the upper surface of the object to be molded, thereby supplying the resin material filled in the pot to the cavity, and closing the air vent groove by a second mold clamping force;
and a molding step of resin-molding the molding object. A method for manufacturing a resin molded product as described in claim 4, wherein, in the mold clamping process, after the cull block and the pot block are brought into contact by the elastic force of the second elastic member, the second elastic member is compressed to bring the lower surface of the upper mold cavity block into contact with the upper surface of the molded object. 6. The method for producing a resin molded product according to claim 4, wherein in the mold clamping step, the air vent groove is closed when a compression amount of the support member becomes maximum due to the second mold clamping force. 6. The method for producing a resin molded product according to claim 4, wherein when an amount of elastic deformation of the first elastic member is maximized, the upper surface of the molded object and an upper surface of the pot block become flush with each other. 7. The method for producing a resin molded product according to claim 6, wherein when an amount of elastic deformation of the first elastic member is maximized, the upper surface of the molded object and an upper surface of the pot block become flush with each other.

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