Resin molding device, and method for producing resin molded article

Abstract

To provide a resin molding device capable of finely adjusting an interval between a lower platen and an upper platen.SOLUTION: There is provided a resin molding device, which comprises: an upper platen to which an upper mold is fixed; a lower platen to which a lower mold is fixed; a plurality of tie bars which connects the upper platen and the lower platen; a mold clamping mechanism which moves the lower platen up and down; and a position adjustment mechanism which is capable of adjusting, for each tie bar, a position of the upper platen with respect to the tie bars.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to the technology of resin molding apparatuses and methods for manufacturing resin molded products.

Background Art

[0002] In a resin molding apparatus using a mold clamping mechanism, for example, when the mold is replaced and the mold thickness changes, it is necessary to adjust the distance between the movable platen and the fixed platen. Patent Document 1 discloses a mold pressure adjusting device for an injection molding apparatus. This mold pressure adjusting device can adjust the position of the fixed platen (end housing) left and right by synchronously rotating nuts provided on four tie bars with one drive source (hydraulic motor).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a resin molding apparatus used for semiconductor manufacturing, for example, since highly accurate products are required, a technology that can more finely adjust the distance between the movable platen and the fixed platen is required.

[0005] 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 capable of finely adjusting the distance between the lower platen and the upper platen, and a method for manufacturing a resin molded product.

Means for Solving the Problems

[0006] The problems to be solved by the present invention are as described above. To solve this problem, a resin molding apparatus according to the present invention includes an upper platen to which an upper mold is fixed, a lower platen to which a lower mold is fixed, a plurality of tie bars connecting the upper platen and the lower platen, a clamping mechanism for moving the lower platen up and down, and a position adjusting mechanism for adjusting the position of the upper platen with respect to each of the tie bars.

[0007] Further, a method for manufacturing a resin molded product according to the present invention is a method for manufacturing a resin molded product using the resin molding apparatus, and includes an adjustment step of adjusting the position of the upper platen with respect to the tie bar, a clamping step of moving the lower platen with respect to the upper platen to perform clamping after the adjustment step, and a resin molding step of resin molding an object to be molded after the clamping step.

Advantages of the Invention

[0008] According to the present invention, the distance between the lower platen and the upper platen can be finely adjusted.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0010] Hereinafter, the directions indicated by the arrows U, D, L, R, F, and B shown in the figure will be defined as the upward direction, downward direction, left direction, right direction, forward direction, and backward direction, respectively, for the description.

[0011] <Overall Configuration of Resin Molding Apparatus 1> First, the configuration of the resin molding apparatus 1 will be described with reference to FIG. 1. The resin molding apparatus 1 resin-seals an electronic element such as a semiconductor chip (hereinafter simply referred to as "chip 2a" (see FIG. 3)) to manufacture a resin molded product. In particular, in this embodiment, a resin molding apparatus 1 that performs resin molding using the transfer molding method is exemplified. Note that the chip 2a is not shown except in FIG. 3.

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

[0013] <Supply Module 10> The supply module 10 supplies a lead frame 2, which is a kind of substrate with a chip 2a mounted thereon, and a resin tablet T to the resin molding module 20. Note that the lead frame 2 is one embodiment of the object to be molded according to the present invention. In this embodiment, the lead frame 2 is exemplified as an example of the substrate to be molded, but other various substrates (such as glass epoxy substrates, ceramic substrates, resin substrates, metal substrates, etc.) can also be used in addition to the lead frame 2. The supply module 10 mainly includes a frame delivery unit 11, a frame supply unit 13, a resin material supply mechanism 14, a loader 17, and a control unit 18.

[0014] The frame delivery unit 11 sends out the resin unsealed lead frame 2 housed in an in-magazine unit (not shown) to the frame supply unit 13. The frame supply unit 13 receives the lead frame 2 from the frame delivery unit 11, appropriately aligns the received lead frame 2, and delivers it to the loader 17.

[0015] The resin material supply mechanism 14 supplies the resin tablet T to the 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 frame 2 and the 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 is equipped with a heater plate (not shown) for preheating the lead frame 2 in advance. The heater plate is heated by a heating device while the loader 17 is on standby. Also, the heater plate can heat the lead frame 2 during the transportation of the lead frame 2 by the loader 17.

[0017] In addition, the loader 17 is provided with a cleaning mechanism 17a for cleaning the molding dies (lower die 160 and upper die 170) described later. As the cleaning mechanism 17a, for example, a dust collecting mechanism capable of sucking dust adhering to the surface of the molding die can be used. The cleaning mechanism 17a is provided, for example, at the front end of the loader 17.

[0018] The control unit 18 controls the operations of the respective modules of the resin molding apparatus 1. The operations of the supply module 10, the resin molding module 20, and the unloading module 30 are controlled by the control unit 18. Also, the operations of the respective modules can be arbitrarily changed (adjusted) using the control unit 18.

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

[0020] <Resin molding module 20> The resin molding module 20 resin-seals the chip 2a mounted on the lead frame 2. In the present embodiment, two resin molding modules 20 are arranged side by side. Note that only one resin molding module 20 may be provided, or three or more resin molding modules 20 may be provided. By performing the resin sealing of the lead frame 2 in parallel by a plurality of resin molding modules 20, the manufacturing efficiency of the resin molded product can be improved. The resin molding module 20 mainly includes a molding mechanism 100.

[0021] The molding mechanism 100 mainly includes a molding die (lower die 160 and upper die 170) and a die clamping mechanism 150 (see FIG. 2).

[0022] The molding die (lower die 160 and upper die 170) uses a molten resin material to resin-seal the chip 2a mounted on the lead frame 2. The molding die includes a pair of upper and lower dies, that is, a lower die 160 and an upper die 170 (see FIG. 2 etc.).

[0023] The die clamping mechanism 150 (see FIG. 2) clamps or opens the molding die (lower die 160 and upper die 170) by moving the lower die 160 up and down. The specific configuration of the molding mechanism 100 will be described later.

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

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

[0026] <Molding mechanism 100> Next, with reference to FIGS. 2 to 4, the specific configuration of the molding mechanism 100 will be described.

[0027] Note that FIG. 2 is a diagram schematically showing the configuration of the molding mechanism 100. FIG. 3 is a diagram schematically showing the extraction of the mold (lower mold 160 and upper mold 170) from the configuration shown in FIG. 2. FIG. 4 is a diagram schematically showing the configuration of the position adjustment mechanism 190 (individual adjustment mechanism 200).

[0028] As shown in FIG. 2, the molding mechanism 100 mainly includes a base 110, tie bars 120, a movable platen 130, a fixed platen 140, a clamping mechanism 150, a mold (lower mold 160 and upper mold 170), a transfer mechanism 180, and a position adjustment mechanism 190.

[0029] The base 110 supports the tie bars 120 and the clamping mechanism 150. The base 110 is formed in a rectangular parallelepiped shape having an appropriate vertical width.

[0030] The tie bars 120 connect the movable platen 130 and the fixed platen 140. The tie bars 120 are formed in a longitudinal shape with the longitudinal direction oriented in the vertical direction. In this embodiment, the tie bars 120 are formed in a cylindrical shape. The lower part of the tie bars 120 is fixed to the base 110. A plurality of tie bars 120 are provided. In this embodiment, four tie bars 120 are provided and are respectively arranged at the four corners of the base 110. Note that the number of tie bars 120 is not limited to four, and the number and arrangement of the tie bars 120 can be arbitrarily changed.

[0031] The movable platen 130 is fixed to the lower mold 160 and moves the lower mold 160 up and down. The movable platen 130 is an embodiment of the lower platen according to the present invention. The movable platen 130 is formed in a rectangular parallelepiped shape having an appropriate vertical width. The middle part in the vertical direction of the tie bar 120 is inserted so as to penetrate the four corners of the movable platen 130 vertically. Thereby, the movable platen 130 can move up and down along the tie bar 120. A lower mold chase holder 131 for holding the lower mold 160 is provided on the upper part of the movable platen 130.

[0032] The fixed platen 140 is for fixing the upper mold 170. The fixed platen 140 is an embodiment of the upper platen according to the present invention. The fixed platen 140 is formed in a rectangular parallelepiped shape having an appropriate vertical width. The fixed platen 140 is disposed above the movable platen 130. The upper part of the tie bar 120 is inserted into through holes 140a (see FIG. 4) formed at the four corners of the fixed platen 140 so as to penetrate the fixed platen 140 vertically. The fixed platen 140 is fixed to the tie bar 120 via a position adjusting mechanism 190. An upper mold chase holder 141 for holding the upper mold 170 is provided at the lower part of the fixed platen 140. A pressure regulating plate 142 for adjusting the vertical position of the upper mold chase holder 141 is disposed between the fixed platen 140 and the upper mold chase holder 141. By appropriately changing the thickness (vertical width) of the pressure regulating plate 142, the vertical position of the upper mold chase holder 141 with respect to the fixed platen 140 can be adjusted. By adjusting the vertical position of the upper mold chase holder 141 using the pressure regulating plate 142, it is possible to adjust the mold contact, clamping force, etc. when performing mold clamping.

[0033] The mold clamping mechanism 150 clamps or opens the molding die (lower mold 160 and upper mold 170) by moving the movable platen 130 up and down. The mold clamping mechanism 150 mainly includes a toggle link 151, a lifting member 152, and a ball screw 153.

[0034] The toggle link 151 is a link mechanism that connects the base 110 and the movable platen 130. The toggle link 151 is configured to be vertically extensible by combining a plurality of link members. The vertical middle part of the toggle link 151 is connected to the lifting member 152. The lifting member 152 is fitted onto the ball screw 153. The ball screw 153 is arranged with its longitudinal direction oriented vertically. By rotating the ball screw 153 by a drive source (not shown) such as a servo motor, the lifting member 152 can be lifted and lowered vertically. As the lifting member 152 moves up and down, the toggle link 151 is operated, and the movable platen 130 can be moved vertically with respect to the base 110.

[0035] The lower mold 160 shown in FIGS. 2 and 3 forms the lower part of the mold. The lower mold 160 is fixed to the upper part of the movable platen 130. The lower mold 160 mainly includes a pot 161 and a lower mold heater 162.

[0036] The pot 161 shown in FIG. 3 is a part for accommodating the resin tablet T. The pot 161 is formed to penetrate the lower mold 160 vertically. The pot 161 is formed at the left - right center of the lower mold 160. The pots 161 are formed to be arranged in a plurality in the front - rear direction (not shown). In this embodiment, a so - called two - sheet arrangement in which the lead frames 2 are arranged on the left and right of the pot 161 of the lower mold 160 is adopted, but a configuration in which only one lead frame 2 is arranged on the lower mold 160 or a configuration in which three or more lead frames 2 are arranged on the lower mold 160 may also be used.

[0037] The lower mold heater 162 is for heating the lower mold 160 when performing resin molding. The lower mold heater 162 is provided inside the lower mold 160.

[0038] The upper mold 170 shown in FIGS. 2 and 3 forms the upper part of the mold. The upper mold 170 mainly includes a concave portion 171, a resin flow path 172, and an upper mold heater 173.

[0039] The recess 171 shown in Fig. 3 is a portion that forms a cavity, which is a space for resin encapsulation, between the lead frame 2 and the upper mold 170 when the lead frame 2 is placed on the lower mold 160 and the lower mold 160 and the upper mold 170 are closed. The chip 2a fixed to the lead frame 2 is accommodated in the cavity, and the chip 2a is resin-encapsulated with the resin material supplied to the cavity. The recess 171 is formed by recessing the lower surface of the upper mold 170 upward. The recess 171 is formed at a position and in a shape corresponding to the shape of the product (resin molded product), etc.

[0040] The resin flow path 172 is a portion that guides the melted resin tablet T (resin material) to the recess 171 (cavity) when the lead frame 2 is placed on the lower mold 160 and the lower mold 160 and the upper mold 170 are closed. The resin flow path 172 is formed by recessing the lower surface of the upper mold 170 upward. The resin flow path 172 is formed so as to connect the pot 161 and the recess 171 (cavity) when the lower mold 160 and the upper mold 170 are closed.

[0041] The upper mold heater 173 is for heating the upper mold 170 when performing resin molding. The upper mold heater 173 is provided inside the upper mold 170.

[0042] Note that the shapes, etc. of the lower mold 160 and the upper mold 170 described in this embodiment are examples, and can be arbitrarily changed according to the shape, number, etc. of the product.

[0043] The transfer mechanism 180 shown in Figs. 2 and 3 supplies the resin material to the cavity. The transfer mechanism 180 mainly includes a plunger 181 and a transfer drive unit (not shown).

[0044] The plunger 181 shown in Fig. 3 injects the resin tablet T (resin material) accommodated in the pot 161 and supplies it to the cavity. The plunger 181 is arranged so as to be movable up and down (ascend and descend) in the pot 161.

[0045] The transfer drive unit (not shown) moves the plunger 181 in the vertical direction (drive source). The transfer drive unit (not shown) can be configured by, for example, a servo motor, an air cylinder, or the like.

[0046] <Position adjustment mechanism 190> The position adjustment mechanism 190 shown in FIGS. 2 and 4 is for adjusting the position of the fixed platen 140 with respect to the tie bar 120 for each tie bar 120. The position adjustment mechanism 190 mainly includes a plurality of individual adjustment mechanisms 200, a strain gauge 260, and an adjustment control unit 270.

[0047] The individual adjustment mechanism 200 is provided for each of the plurality of tie bars 120 and adjusts the position of the fixed platen 140 with respect to the provided tie bar 120. In the present embodiment, four individual adjustment mechanisms 200 are provided so as to correspond to the four tie bars 120.

[0048] Hereinafter, the configuration of the individual adjustment mechanism 200 will be described with reference to FIG. 4. Since the configurations of the four individual adjustment mechanisms 200 are the same, hereinafter, one of them will be focused on for the description. The individual adjustment mechanism 200 mainly includes a support member 210, a connecting member 220, a spring 230, an adjustment nut 240, and a change mechanism 250.

[0049] The support member 210 is for supporting the fixed platen 140 via the spring 230. The support member 210 mainly includes a pair of upper and lower plates (lower plate 211 and upper plate 212), and a column portion 213.

[0050] The lower plate 211 is formed, for example, in a rectangular plate shape. The lower plate 211 is arranged with its plate surface generally horizontal. The central portion of the lower surface of the lower plate 211 is fixed to the upper end of the tie bar 120. A plurality of through holes 211a are formed in the lower plate 211. The through holes 211a are formed, for example, one at each of the four corners of the lower plate 211.

[0051] The upper plate 212 is formed, for example, in substantially the same shape (rectangular plate shape) as the lower plate 211. The upper plate 212 is disposed above the lower plate 211 and parallel to the lower plate 211. The upper plate 212 is disposed so as to be located above the connecting member 220. Thus, the upper plate 212 can regulate the excessive upward movement of the connecting member 220 by contacting the upper end of the connecting member 220.

[0052] The column portion 213 is formed in a columnar shape with its longitudinal direction oriented in the vertical direction. The lower part of the column portion 213 is fixed to the lower plate 211. The upper part of the column portion 213 is fixed to the upper plate 212. For example, a plurality of column portions 213 are provided. The lower plate 211 and the upper plate 212 are connected by the column portions 213.

[0053] The connecting member 220 is for connecting the fixed platen 140 and the support member 210. The connecting member 220 is formed in a columnar shape (e.g., cylindrical shape) with its longitudinal direction oriented in the vertical direction. A plurality (four in this embodiment) of connecting members 220 are provided at positions corresponding to the through holes 211a of the lower plate 211. The connecting members 220 are arranged so as to pass vertically through the through holes 211a of the lower plate 211. The lower end portion of the connecting member 220 is fixed to the fixed platen 140. A circular flat flange portion 221 is formed at the upper end of the connecting member 220. The flange portion 221 is disposed between the lower plate 211 and the upper plate 212.

[0054] The spring 230 is for applying an upward force to the fixed platen 140. Note that the spring 230 is an embodiment of the applying member according to the present invention. The spring 230 is formed by a compression coil spring. The spring 230 is disposed between the lower plate 211 and the flange portion 221 of the connecting member 220. Thus, the spring 230 can apply a force to push up the flange portion 221 (connecting member 220) upward with respect to the flange portion 221.

[0055] The adjustment nut 240 is for restricting the upward movement of the fixed platen 140. Note that the adjustment nut 240 is one embodiment of the restricting member according to the present invention. The diameter of the adjustment nut 240 is formed larger than the inner diameter of the through hole 140a of the fixed platen 140. The adjustment nut 240 is fitted onto a male screw (not shown) formed on the upper part of the tie bar 120. By rotating the adjustment nut 240, the adjustment nut 240 can be moved in the vertical direction with respect to the tie bar 120.

[0056] The change mechanism 250 is for changing the vertical position of the adjustment nut 240. The change mechanism 250 mainly includes a servo motor 251 and a transmission part (a reduction mechanism 252, a drive gear 253, and a driven gear 254) for transmitting the power of the servo motor 251.

[0057] The servo motor 251 serves as a drive source for moving the adjustment nut 240. The rotational position and rotational speed of the servo motor 251 are controlled based on an external control signal. The servo motor 251 is arranged on the side of the support member 210.

[0058] The reduction mechanism 252 is for reducing the rotational speed of the servo motor 251. The reduction mechanism 252 is constituted by, for example, a plurality of gears, a housing for accommodating the gears, etc. The reduction mechanism 252 is provided below the servo motor 251.

[0059] The drive gear 253 rotates by the power output from the reduction mechanism 252. The drive gear 253 is provided below the reduction mechanism 252. The drive gear 253 is connected to the output shaft (not shown) of the reduction mechanism 252 and rotates by the power transmitted from the servo motor 251 via the reduction mechanism 252. The servo motor 251, the reduction mechanism 252, and the drive gear 253 are supported on the upper surface of the fixed platen 140.

[0060] The driven gear 254 is for transmitting the rotation of the driving gear 253 to the adjustment nut 240. The driven gear 254 is formed on the outer peripheral surface of the adjustment nut 240. Note that the driven gear 254 can be integrally formed with the adjustment nut 240 or formed as a separate member from the adjustment nut 240. The driven gear 254 is arranged to mesh with the driving gear 253.

[0061] The strain gauge 260 shown in FIG. 2 is for measuring the strain generated in the tie bar 120. The strain gauges 260 are respectively provided on a plurality of tie bars 120. It is desirable that the strain gauge 260 be provided at a position not easily affected by heat during resin molding. In the present embodiment, an example is shown in which the strain gauge 260 is provided at the lower part of the tie bar 120 (near the base 110). The strain gauge 260 can measure the vertical strain of the tie bar 120.

[0062] The adjustment control unit 270 is for controlling the operation of the servo motor 251. The adjustment control unit 270 is mainly composed of an arithmetic processing device such as a CPU and storage devices such as a RAM and a ROM. Information and various programs necessary for controlling the operation of the servo motor 251 are stored in the storage device of the adjustment control unit 270. Note that in the present embodiment, the control unit 18 (see FIG. 1) and the adjustment control unit 270 are separately illustrated, but it is also possible to integrally configure the adjustment control unit 270 with the control unit 18 (see FIG. 1).

[0063] The adjustment control unit 270 is provided with various input devices (not shown) such as a touch panel, a keyboard, and a switch. By using the input device, various information regarding the operation of the servo motor 251 can be input to the adjustment control unit 270. Further, the adjustment control unit 270 is provided with various display devices (not shown) such as a liquid crystal panel, a touch panel, and a lamp. By using the display device, various information regarding the operation of the servo motor 251 can be displayed.

[0064] The adjustment control unit 270 is connected to each strain gauge 260 and can acquire the measurement results of each strain gauge 260. Further, the adjustment control unit 270 is connected to the servo motor 251 and can transmit a control signal to the servo motor 251 to control the operation of the servo motor 251.

[0065] In addition, the adjustment of the position of the fixed platen 140 using the position adjustment mechanism 190 (individual adjustment mechanism 200) as described later can be performed manually by the operator or automatically by the adjustment control unit 270. When the operator manually adjusts the position of the fixed platen 140, the operator can check the measurement results of the strain gauge 260 and the like on the display device and operate the servo motor 251 according to the measurement results. Further, when the adjustment control unit 270 automatically adjusts the position of the fixed platen 140, the adjustment control unit 270 can control the operation of the servo motor 251 based on various measured information (for example, the measurement results of the strain gauge 260 and the like) and various programs.

[0066] <Operation of the individual adjustment mechanism 200> Hereinafter, the operation mode of the individual adjustment mechanism 200 will be described.

[0067] As shown in FIG. 4, the connecting member 220 is pushed upward by the spring 230. Therefore, the fixed platen 140 is pushed upward along the tie bar 120 via the connecting member 220. When the upper surface of the fixed platen 140 contacts the adjustment nut 240, the upward movement of the fixed platen 140 is restricted. In this way, the vertical position of the fixed platen 140 with respect to the tie bar 120 can be determined by the vertical position of the adjustment nut 240.

[0068] For example, when moving the fixed platen 140 upward with respect to the tie bar 120, as shown in FIG. 5(a), the servo motor 251 is driven to move the adjustment nut 240 upward with respect to the tie bar 120. By moving the adjustment nut 240 upward, a gap is generated between the adjustment nut 240 and the fixed platen 140.

[0069] When a gap occurs between the adjustment nut 240 and the fixed platen 140, as shown in FIG. 5(b), the fixed platen 140 is pushed upward by the spring 230. The upward movement of the fixed platen 140 is restricted by contacting the adjustment nut 240. By moving the adjustment nut 240 upward in this way, the fixed platen 140 can be moved upward with respect to the tie bar 120.

[0070] In addition, in FIG. 5(a), in order to explain the operation of the individual adjustment mechanism 200 step by step, a state in which a gap occurs between the adjustment nut 240 and the fixed platen 140 is illustrated. However, in actuality, the fixed platen 140 also moves upward following the upward movement of the adjustment nut 240. For this reason, almost no gap occurs between the adjustment nut 240 and the fixed platen 140.

[0071] On the other hand, when moving the fixed platen 140 downward with respect to the tie bar 120, although not shown in the figure, the servo motor 251 is driven to move the adjustment nut 240 downward with respect to the tie bar 120. Thereby, the fixed platen 140 can be pushed downward through the adjustment nut 240 to move the fixed platen 140 downward.

[0072] <Adjustment method by the position adjustment mechanism 190> Hereinafter, an example of a method for adjusting the position of the fixed platen 140 using the position adjustment mechanism 190 will be described.

[0073] First, an example of a method for adjusting the clamping force by adjusting the overall position of the fixed platen 140 using the position adjustment mechanism 190 will be described.

[0074] Generally, the molding mechanism 100 using the toggle link 151 as in this embodiment is designed to perform mold clamping near the top dead center of the toggle link 151 (the state where the toggle link 151 is fully extended) and obtain the clamping force required for resin molding. However, when the thickness of the mold or the lead frame 2 is changed, or when changes occur in the dimensions of each part due to the aging of the component parts (for example, the top dead center of the toggle link 151, etc.), the mold clamping position (clamping position) may change, and the required clamping force may not be obtained. Therefore, in this embodiment, by adjusting the position of the fixed platen 140 by the position adjustment mechanism 190, the position of the fixed platen 140 can be adjusted so as to obtain the required clamping force.

[0075] Specifically, with the lead frame 2 placed on the lower mold 160, the mold clamping mechanism 150 is operated to perform mold clamping in the same manner as when actual resin molding is performed. In this state, at least one of the clamping force and the clamping position is measured. Note that the clamping force can be measured using a measuring device such as a load cell. Also, the clamping position can be measured using the rotational position of the servo motor of the mold clamping mechanism 150 or various measuring devices.

[0076] Next, based on the measurement results of the clamping force or the clamping position, the operation of the servo motor 251 of each individual adjustment mechanism 200 is controlled. Specifically, the position of the fixed platen 140 is adjusted up and down so as to obtain the position where the required clamping force is obtained or an appropriate clamping position. At this time, the servo motors 251 of all the individual adjustment mechanisms 200 are controlled to rotate by the same amount. As a result, the fixed platen 140 can be translated without tilting its posture. In this way, by adjusting the overall position of the fixed platen 140, the mold clamping position (clamping position) and the clamping force can be adjusted. Also, by adjusting the position of the fixed platen 140, mold clamping can be performed near the top dead center of the toggle link 151, so the capacity of the drive source (such as a servo motor) of the mold clamping mechanism 150 can be optimized, and the component cost can be reduced and the components can be miniaturized.

[0077] Next, an example of a method for adjusting the mold hitting is described by adjusting the position of the fixed platen 140 for each tie bar 120 using the position adjustment mechanism 190. Hereinafter, as a method for adjusting the mold hitting, two types of methods (a first adjustment method and a second adjustment method) will be described.

[0078] Note that hereinafter, as shown in FIGS. 6 and 7, in order to distinguish the four tie bars 120, symbols A to D are attached to the symbols in the counterclockwise order from the left front tie bar 120 in a plan view for explanation. Similarly, symbols A to D are attached to the symbols of the individual adjustment mechanisms 200 corresponding to the respective tie bars 120A to 120D for explanation. Further, hereinafter, specific numerical values such as strain are exemplified, but these numerical values are provisional values for explanation, and the present invention does not limit various numerical values.

[0079] First, the first adjustment method will be described with reference to FIG. 6. The first adjustment method is a method for adjusting the mold hitting based on the strain of each tie bar 120 when clamping with a constant clamping force. Specifically, as shown in FIG. 6(a), the strain (ε) of each tie bar 120 in a state where clamping is performed with an appropriate clamping force is measured. In FIG. 6, the strains of the respective tie bars 120A to 120D are shown as ε(A) to ε(D), respectively.

[0080] In the example shown in FIG. 6(a), it can be seen that the strain of the right front tie bar 120B is relatively large. From this, it is inferred that the mold hitting on the right front side of the mold is strong. Also, in the example shown in FIG. 6(a), it can be seen that the strain of the left rear tie bar 120D is relatively small. From this, it is inferred that the mold hitting on the left rear side of the mold is weak. Therefore, by adjusting the position of the fixed platen 140 with respect to each tie bar 120 so that the strain of each tie bar 120 becomes constant, the uniformity of the mold hitting of the mold can be achieved.

[0081] Specifically, as shown in Fig. 6(b), the individual adjustment mechanism 200B corresponding to the tie bar 120B with relatively large strain is controlled to move the fixed platen 140 upward with respect to the tie bar 120B. Thereby, the mold contact on the right front side of the mold can be weakened. Also, the individual adjustment mechanism 200D corresponding to the tie bar 120D with relatively small strain is controlled to move the fixed platen 140 downward with respect to the tie bar 120D. Thereby, the mold contact on the left rear side of the mold can be strengthened.

[0082] In this way, the measurement of the strain of each tie bar 120 and the control of the individual adjustment mechanism 200 are repeated several times to adjust the position of the fixed platen 140 so that the strain of each tie bar 120 becomes constant as shown in Fig. 6(b). Thereby, the mold contact of the mold can be adjusted to be uniform.

[0083] Next, the second adjustment method will be described with reference to Fig. 7. The second adjustment method is a method of adjusting the mold contact based on the clamp position when the same strain occurs in each tie bar 120. Specifically, as shown in Fig. 7(a), the clamp position when the strain (ε) of each tie bar 120 becomes 100 is measured. In Fig. 7, the clamp positions when the strains of the tie bars 120A to 120D become 100 are shown as CL POS(A) to CL POS(D), respectively. The clamp position is represented by the amount of movement of the lower mold 160 rising with an appropriate position as a reference.

[0084] To explain using the specific example shown in Fig. 7(a), when the lower mold 160 is lifted using the clamping mechanism 150 and pressed against the upper mold 170, a load is applied to each tie bar 120 and strain occurs in each tie bar 120. When the clamp position is gradually increased (lifting the lower mold 160), first, when the clamp position reaches 99.8 (mm), the strain of tie bar 120B becomes 100. When the clamp position is further increased, when the clamp position reaches 100 (mm), the strain of tie bars 120A and 120C becomes 100. When the clamp position is further increased, when the clamp position reaches 100.1 (mm), the strain of tie bar 120D becomes 100.

[0085] In the example shown in Fig. 7(a), it can be seen that at a relatively early stage (when the clamp position is small), the strain of the right front tie bar 120B reaches 100. From this, it is inferred that the mold hitting on the right front side of the mold is strong. Also, in the example shown in Fig. 7(a), it can be seen that at a relatively late stage (when the clamp position is large), the strain of the left rear tie bar 120D reaches 100. From this, it is inferred that the mold hitting on the left rear side of the mold is weak. Therefore, by adjusting the position of the fixed platen 140 with respect to each tie bar 120 so that the same strain occurs in each tie bar 120 at the same timing (same clamp position), the uniformity of the mold hitting of the mold can be achieved.

[0086] Specifically, as shown in Fig. 7(b), the individual adjustment mechanism 200B corresponding to the tie bar 120B whose strain reaches 100 at a relatively early stage is controlled to move the fixed platen 140 upward with respect to the tie bar 120B. Thereby, the mold hitting on the right front side of the mold can be weakened. Also, the individual adjustment mechanism 200D corresponding to the tie bar 120D whose strain reaches 100 at a relatively late stage is controlled to move the fixed platen 140 downward with respect to the tie bar 120D. Thereby, the mold hitting on the left rear side of the mold can be strengthened.

[0087] In this way, the measurement of the clamp position when the strain reaches 100 and the control of the individual adjustment mechanism 200 are repeated several times, and as shown in FIG. 7(b), the position of the fixed platen 140 is adjusted so that the strain of each tie bar 120 reaches 100 at the same timing (clamp position). Thereby, it is possible to adjust so that the mold hitting of the mold becomes uniform.

[0088] As described above, in the present embodiment, since the position of the fixed platen 140 with respect to the tie bar 120 can be adjusted for each tie bar 120, the position of the fixed platen 140 (the distance between the fixed platen 140 and the movable platen 130) can be finely adjusted. Further, since the position of the fixed platen 140 can be adjusted using the position adjustment mechanism 190, the position adjustment of the fixed platen 140 using the pressure regulating plate 142 can be omitted or simplified. Thereby, the work burden of the operator required for the position adjustment work of the fixed platen 140 can be reduced.

[0089] <Outline of the operation of the resin molding apparatus 1> Next, with reference to FIGS. 1 and 8, an outline of the operation of the resin molding apparatus 1 (a method for manufacturing a resin molded product using the resin molding apparatus 1) configured as described above will be described.

[0090] First, if necessary, the position of the fixed platen 140 is adjusted (step S11 in FIG. 8). Specifically, as described above, the adjustment of the clamping force and the adjustment of the mold hitting using the position adjustment mechanism 190 are performed. The position adjustment of the fixed platen 140 in step S11 is performed at the necessary timing when the mold is replaced, when starting the resin molding of different types of lead frames 2 or lead frames 2 with different lot numbers, or when adjustment is required due to dimensional changes of each part due to aging of the components. In other words, if adjustment is not necessary, the adjustment in step S11 can be omitted.

[0091] Next, the lead frame 2 and the resin tablet T are delivered to the loader 17 (step S12 in FIG. 8). Specifically, in the supply module 10 shown in FIG. 1, the frame delivery unit 11 sends out the lead frame 2 accommodated in an in-magazine unit (not shown) to the frame supply unit 13. The frame supply unit 13 appropriately aligns the received lead frame 2 and delivers it to the loader 17.

[0092] Also, the resin material supply mechanism 14 delivers the number of resin tablets T required for one resin molding in the resin molding module 20 to the loader 17.

[0093] Next, the loader 17 is made to enter the mold (step S13 in FIG. 8). 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 the loader 17 moves to the mold of the molding mechanism 100 from the rear. Thereafter, the loader 17 places the lead frame 2 on the upper surface of the lower mold 160 and stores (sets) the resin tablet T in the pot 111 of the lower mold 160 (step S14 in FIG. 8).

[0094] After placing the lead frame 2 on the lower mold 160 and storing the resin tablet T in the pot 111, the loader 17 retreats rearward from the mold (step S15 in FIG. 8).

[0095] Next, the mold clamping mechanism 150 clamps the mold (step S16 in FIG. 4). Specifically, the mold clamping mechanism 150 is driven to raise the lower mold 160 toward the upper mold 170. When the lower mold 160 approaches the upper mold 170, the lead frame 2 will be sandwiched between the lower mold 160 and the upper mold 170.

[0096] Next, the transfer mechanism 180 injects the resin material into the cavity (step S17 in FIG. 8). Specifically, the resin tablet T stored in the pot 111 is heated and melted by heaters (lower mold heater 114 and upper mold heater 123) provided in the mold. The transfer mechanism 180 can inject the melted resin tablet T (resin material) into the cavity by raising the plunger 181.

[0097] After the resin material is injected by the transfer mechanism 180, by waiting until a predetermined time elapses, the resin material can be cured to resin-seal the chip 2a of the lead frame 2.

[0098] Next, the mold clamping mechanism 150 opens the mold (step S18 in FIG. 8). Specifically, the mold clamping mechanism 150 is driven to lower the lower mold 160 away from the upper mold 170. Thereby, the resin-sealed lead frame 2 can be released from the upper mold 170. Thereafter, the lead frame 2 is unloaded from the mold (step S19 in FIG. 8). Specifically, the lead frame 2 is unloaded from the mold by the unloader 31 shown in FIG. 1 and stored in the substrate storage portion 32 of the unloading module 30. In this way, the resin-sealed lead frame 2 (resin molded product) is manufactured.

[0099] As described above, the embodiments of the present invention have been described. However, the present invention is not limited to the above embodiments, and appropriate modifications can be made within the scope of the technical idea of the invention described in the claims.

[0100] For example, in the above-described embodiment, an example was shown in which adjustment such as die hitting was performed by controlling the position adjustment mechanism 190 based on the strain generated in the tie bar 120. However, the present invention is not limited to this. For example, by using various measuring devices such as a dial gauge and a displacement gauge to measure the distance between the movable platen 130 and the fixed platen 140 (for example, the distances at the four corners), and controlling the position adjustment mechanism 190 so that both are parallel, it is also possible to perform die hitting adjustment. Note that it is possible to control the position adjustment mechanism 190 based not only on the strain of the tie bar 120 and the distance between the platens, but also on various information serving as a standard for die hitting.

[0101] Further, in the present embodiment, a toggle link type clamping mechanism 150 that raises the lower die 160 toward the upper die 170 using a toggle link 151 is illustrated. However, the present invention is not limited to this. For example, the present invention can also be applied to a linear motion shaft type clamping mechanism that linearly raises the lower die 160 toward the upper die 170 using a ball screw, a hydraulic (oil pressure) cylinder, or the like. Further, the drive source of the clamping mechanism 150 is not limited to a servo motor, and various drive sources such as hydraulic (oil pressure) and pneumatic can also be used.

[0102] Further, in the present embodiment, as an example of a member that applies a force to the fixed platen 140, a spring 230 formed of a compression coil spring was illustrated. However, the present invention is not limited to this. For example, as the member that applies a force, various members capable of applying a force such as a tension coil spring, a leaf spring, and a cylinder can be used.

[0103] Further, in the present embodiment, as an example of a regulating member that regulates the upward movement of the fixed platen 140, an adjusting nut 240 was illustrated. However, the present invention is not limited to this. As the regulating member, various members capable of changing the vertical position can be used.

[0104] In addition, in this embodiment, the molding mechanism 100 including the pressure regulating plate 142 is illustrated, but the present invention is not limited thereto. For example, it is also possible to omit the pressure regulating plate 142 and adjust the mold hitting and the clamping force only by the position adjusting mechanism 190.

[0105] Further, the configuration of the position adjusting mechanism 190 (individual adjusting mechanism 200) described in this embodiment is an example, and the configuration can be arbitrarily changed as long as the position of the fixed platen 140 can be adjusted for each tie bar 120. For example, in this embodiment, an example in which a drive source (servo motor 251) is provided for each individual adjusting mechanism 200 is shown, but it is also possible to adopt a configuration in which each individual adjusting mechanism 200 is operated using a common (one) drive source. In this case, for example, by providing a mechanism for switching the availability of power transmission from the drive source to each individual adjusting mechanism 200, the individual adjusting mechanisms 200 can be operated independently of each other.

[0106] In addition, although not particularly 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 170).

[0107] In addition, in the above embodiment, the molding die composed of the lower die 160 and the upper die 170 is taken as an example for explanation, but for example, it is also possible to use a molding die including an intermediate die.

[0108] In addition, in the above embodiment, the resin molding apparatus 1 using the transfer molding method is taken as an example for explanation, but the present invention is not limited thereto, and it is also possible to apply it to a resin molding apparatus using the compression molding method.

[0109] <Appendix> The resin molding apparatus 1 according to the first aspect of the present disclosure is a fixed platen 140 (upper platen) to which the upper die 170 is fixed, a movable platen 130 to which the lower die 160 is fixed, a plurality of tie bars 120 connecting the fixed platen 140 and the movable platen 130, A clamping mechanism 150 for moving the movable platen 130 up and down, and a position adjusting mechanism 190 for adjusting the position of the fixed platen 140 with respect to each of the tie bars 120, the position adjusting mechanism 190 being capable of adjusting the position for each tie bar 120. The resin molding apparatus 1 is provided with these components. According to the resin molding apparatus 1 of the first aspect of the present disclosure, the interval between the fixed platen 140 and the movable platen 130 can be finely adjusted. As a result, the clamping force, the mold contact, etc. can be finely adjusted.

[0110] The position adjusting mechanism 190 of the second aspect according to the first aspect is provided on each of the plurality of tie bars 120 and includes a plurality of individual adjusting mechanisms 200 capable of adjusting the position of the fixed platen 140 with respect to the tie bar 120. According to the resin molding apparatus 1 of the second aspect of the present disclosure, the interval between the fixed platen 140 and the movable platen 130 can be finely adjusted.

[0111] The individual adjusting mechanism 200 of the third aspect according to the second aspect includes a spring 230 (applying member) that applies an upward force to the fixed platen 140, an adjusting nut 240 (restricting member) that restricts the upward movement of the fixed platen 140, and a changing mechanism 250 that changes the vertical position of the adjusting nut 240. The resin molding apparatus 1 is provided with these components. According to the resin molding apparatus 1 of the third aspect of the present disclosure, the position of the fixed platen 140 can be adjusted with a simple configuration.

[0112] The changing mechanism 250 of the fourth aspect according to the third aspect includes a servo motor 251 (driving source), and a transmission unit (a reduction mechanism 252, a driving gear 253, and a driven gear 254) that transmits the power of the servo motor 251 to the adjusting nut 240. The resin molding apparatus 1 is provided with these components. According to the resin molding apparatus 1 of the fourth aspect of the present disclosure, the position of the fixed platen 140 can be adjusted with a simple configuration.

[0113] The drive source on the fifth side according to the fourth side is configured by a servo motor 251. According to the resin molding apparatus 1 of the fifth aspect of the present disclosure, the position of the fixed platen 140 can be finely adjusted.

[0114] The transmission part on the sixth side according to the fourth or fifth side is equipped with a speed reduction mechanism 252 that can reduce and transmit the power of the servo motor 251. According to the resin molding apparatus 1 of the sixth aspect of the present disclosure, the torque of the servo motor 251 can be increased. Thereby, the fixed platen 140 can be moved more reliably.

[0115] The mold clamping mechanism 150 on the seventh side according to any one of the first to sixth sides is configured by a toggle link method or a direct acting shaft method. According to the resin molding apparatus 1 of the seventh aspect of the present disclosure, the interval between the fixed platen 140 and the movable platen 130 can be finely adjusted in any method. In particular, in the toggle link method, by adjusting the position of the fixed platen 140, it is possible to adjust so that mold clamping is performed near the top dead center of the toggle link 151, so that the capacity of the drive source of the mold clamping mechanism 150 can be optimized.

[0116] The resin molding apparatus 1 on the eighth side according to any one of the first to seventh sides is provided on each of the plurality of tie bars 120 and includes a strain gauge 260 capable of detecting the strain of the tie bar 120. According to the resin molding apparatus 1 of the eighth aspect of the present disclosure, the interval between the fixed platen 140 and the movable platen 130 (such as the state of mold contact) can be easily estimated. Thereby, the position of the fixed platen 140 can be easily adjusted.

[0117] The manufacturing method of the resin molded product according to the ninth aspect of the present disclosure is a method for manufacturing a resin molded product using any one of the resin molding apparatuses 1 from the first to the eighth aspects, an adjustment step (step S11) of adjusting the position of the fixed platen 140 with respect to the tie bar 120, a mold clamping step (step S16) of moving the movable platen 130 with respect to the fixed platen 140 to perform mold clamping after the adjustment step, a resin molding process (step S17) of resin molding the lead frame 2 (object to be molded) after the mold clamping step, and includes. According to the manufacturing method of the resin molded product according to the ninth aspect of the present disclosure, the interval between the fixed platen 140 and the movable platen 130 can be finely adjusted. Thereby, the clamping force, the mold contact, etc. can be finely adjusted.

Explanation of reference numerals

[0118] 1 Resin molding apparatus 100 Molding mechanism 120 Tie bar 130 Movable platen 140 Fixed platen 160 Lower mold 170 Upper mold 190 Position adjustment mechanism 200 Individual adjustment mechanism 230 Spring 240 Adjusting nut 250 Changing mechanism 251 Servo motor 252 Reduction mechanism 253 Driving gear 254 Driven gear 260 Strain gauge

Claims

1. an upper platen to which the upper mold is fixed, a lower platen to which the lower mold is fixed, a plurality of tie bars connecting the upper platen and the lower platen, a clamping mechanism for moving the lower platen vertically, a position adjustment mechanism for adjusting the position of the upper platen with respect to each of the tie bars, A resin molding apparatus comprising:

2. The position adjustment mechanism includes a plurality of individual adjustment mechanisms provided respectively on the plurality of tie bars and capable of adjusting the position of the upper platen with respect to the tie bars. The resin molding apparatus according to claim 1.

3. Each of the individual adjustment mechanisms includes an applying member that applies an upward force to the upper platen, a restricting member that restricts upward movement of the upper platen, and a changing mechanism that changes the vertical position of the restricting member. The resin molding apparatus according to claim 2.

4. The changing mechanism includes a drive source and a transmission unit that transmits the power of the drive source to the restricting member. The resin molding apparatus according to claim 3.

5. The drive source is constituted by a servo motor. The resin molding apparatus according to claim 4.

6. The transmission unit includes a speed reduction mechanism capable of reducing and transmitting the power of the drive source. The resin molding apparatus according to claim 4 or claim 5.

7. The clamping mechanism is constituted by a toggle link method or a direct acting shaft method. The resin molding apparatus according to any one of claims 1 to 6.

8. A strain gauge provided respectively on the plurality of tie bars and capable of detecting strain of the tie bars. The resin molding apparatus according to any one of claims 1 to 7.

9. A method for manufacturing a resin molded product using the resin molding apparatus according to any one of claims 1 to 8, including an adjustment step of adjusting the position of the upper platen with respect to the tie bars, a clamping step of moving the lower platen with respect to the upper platen to perform clamping after the adjustment step, and a resin molding step of resin molding an object to be molded after the clamping step. A method for manufacturing a resin molded product. ​ ​

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