Patent Application
20210362382
This application claims the priority benefit of Japan Application No. 2020-089927, filed on May 22, 2020. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The present invention relates to a resin molding device in which a workpiece in which an electronic component is mounted on a thin plate type carrier is loaded into a mold frame and compressed and molded.
As an example of a thin plate type carrier, a conveyance device that prevents falling due to deflection of a lead frame and performing conveyance to a mold frame has been proposed.
Positioning pins that are disposed to face each other are inserted into positioning holes, retaining pins are fitted into engaging holes, the lead frame is supported from below by a receiving part, and the lead frame does not fall off of the pins (refer to Patent Document 1: Japanese Patent Laid-Open No. 2018-22730).
[Patent Document 1] Japanese Patent Laid-Open No. 2018-22730
The conveyance device shown in Patent Document 1 described above uses a technology in which, when the lead frame that is a workpiece is erected between the positioning pins fitted into the positioning holes and the retaining pins fitted into the engaging holes, the lead frame is supported from below by the receiving part so that it does not fall while it is assumed that it is deflected due to its own weight. In this manner, since positioning holes are provided in a lead frame that is a carrier for a general mold, the lead frame can be positioned with respect to the frame.
Here, for example, when a workpiece in which an electronic component is mounted on a thin and large-size carrier (a copper plate, a glass plate, etc.) of about 500 mm is supplied to a mold frame, since the carrier has very weak rigidity or is a brittle material, it is difficult to provide positioning holes in the first place, elongation during heating is large due to the large size, and it may be difficult to perform positioning with the positioning holes and the positioning pins provided in the frame. Here, for example, it is conceivable to perform positioning with the external form of the workpiece, but since elongation of the workpiece during heating is large, it may be difficult to dispose the workpiece on the frame so that the centers of the workpiece and the frame are aligned.
The present invention provides a resin molding device in which, when a thin and large-size workpiece is conveyed, even if dimensional tolerance is large and a coefficient of linear expansion of the workpiece differs, it is possible to hold the workpiece without positional displacement and convey it to a mold frame.
The present invention has the following configuration.
A resin molding device in which a workpiece in which an electronic component is mounted on a carrier is conveyed to a mold frame and molded with a resin, including: a workpiece alignment part that adjusts the orientation of the workpiece held on a stage to a reference position; and a loader hand mechanism that holds the workpiece aligned by the workpiece alignment part and conveys it to the mold frame, wherein the loader hand mechanism includes a loader hand that clamps and holds the workpiece on the stage; a position detection unit that detects positional displacement between an external form position of the workpiece provided in the loader hand and a reference position; and an alignment mechanism that aligns a center position of the loader hand with a center position of the workpiece in the X-Y direction according to an amount of positional displacement detected by the position detection unit.
With the above configuration, when the loader hand mechanism holds the workpiece aligned by the workpiece alignment part, since the center position of the loader hand is aligned with the center position of the workpiece according to the amount of positional displacement between the external form position of the workpiece and the reference position in the X-Y direction and the workpiece is then held, when a thin and large-size workpiece is conveyed, even if dimensional tolerance is large and a coefficient of linear expansion of the workpiece differs, it is possible to hold the workpiece without positional displacement and convey it to a mold frame.
Preferably, the workpiece alignment part presses the workpiece against reference blocks provided in the X-Y direction and adjusts the orientation of the workpiece to the reference position. Thereby, the orientation of the workpiece can be reliably adjusted to the reference position.
The position detection unit may include an imaging camera, may read coordinates of the external form of the workpiece disposed on the stage and detect positional displacement in the X-Y direction from a positioning mark (alignment mark) indicating the reference position, may include a plurality of imaging cameras and detect coordinates at diagonal positions of the external form of the workpiece, and may detect positional displacement in the X-Y direction from a virtual stage center position.
Thereby, when simply the external form of the workpiece is imaged, the loader hand can calculate an amount of positional displacement from the reference position in the X-Y direction and align the center position of the loader hand with the center position of the workpiece in the X-Y direction.
The stage may be a preheating stage that preheats the workpiece. Thereby, even if preheating is performed immediately before the workpiece is loaded into the mold frame, it is possible to hold the workpiece without positional displacement and convey it to a mold frame.
The loader hand may include an annular pressing member that presses an outer circumferential part from an upper surface of the workpiece and a chuck that supports a lower surface of the workpiece with a predetermined clearance with the end of the workpiece, and the pressing member may be controlled so that a pressing force of the workpiece is variable, and the loader hand mechanism conveys the workpiece preheated on the preheating stage, which is clamped between the pressing member and the chuck, to the mold frame.
Thereby, even if the workpiece is preheated on the preheating stage and the amount of warpage differs, the flatness of the workpiece can be maintained by changing the pressing force of the pressing member, and the workpiece can be positioned and held while maintaining the flatness of the workpiece with the loader hand.
According to the present invention, it is possible to provide a resin molding device in which, when a thin and large-size workpiece is conveyed, even if dimensional tolerance is large and a coefficient of linear expansion of the workpiece differs, it is possible to hold the workpiece without positional displacement and convey it to a mold frame.
Hereinafter, referring to the drawings, an embodiment of the present invention will be described with reference to
In the compression molding device 1, a workpiece supply unit A, a resin supply unit B, a workpiece delivery unit C, a press unit D, and a cooling unit E are each linked in series. A resin supply stage 7 and a press part 11, which will be described below, are disposed on the front side of the device in consideration of operability and maintenance, and a workpiece transfer part 2 is disposed on the back side of the device.
In the workpiece transfer part 2, a transfer part main body 2a reciprocates between a reception position P and a delivery position Q along a rail part 3 provided between the workpiece supply unit A, the resin supply unit B, and the workpiece delivery unit C (refer to the solid arrow H in
In the resin supply unit B, a dispenser 6 and the resin supply stage 7 through which a granular resin or a liquid resin is supplied is provided. As shown in
In the workpiece delivery unit C, the delivery position Q at which the workpiece W onto which the resin R is supplied is delivered to the loader 4 (loader hand mechanism) is provided. In addition, a unit (not shown) that delivers the workpiece W from a delivery position Q to the loader 4 is provided, and the workpiece W is delivered from the holder plate 5 to the loader 4. In the loader 4, as will be described below, an annular pressing member (a frame 4b1) and a plurality of chuck claws are provided and the loader 4 holds the outer circumferential part of the workpiece W in a vertical insertion manner. The workpiece W held at the delivery position Q by the loader 4 while only its outer circumference is clamped to a preheating part 10 (a preheating stage 10b) of the press unit D is conveyed.
In the workpiece delivery unit C, a cleaner device 9 that removes a resin powder and dust such as foreign substances (contaminants) attached to the back surface of the workpiece W is provided. In addition, the cleaner device 9 is cleaned when the back side of the workpiece W onto which a resin held by the loader 4 is supplied is conveyed to the press unit D (preheating part). The cleaner device 9 in which a cleaner head part is divided into a plurality of parts in the width direction is provided so that the height position can be changed. The cleaner device 9 is provided so that it is vertically movable by a servo mechanism (not shown), and can be cleaned by adjusting the height position in order to avoid deflection of the workpiece W held by the loader 4 and interference with a chuck (not shown) of the loader hand.
In the press unit D, the preheating part 10 and the press part 11 are provided. In the preheating part 10, a preheater 10a is provided. The preheater 10a preheats the workpiece W onto which a resin is supplied that is disposed on the preheating stage 10b (workpiece alignment part) to about 100° C.
The press part 11 includes a mold frame 11a having an upper mold and a lower mold. In the present example, the resin and the workpiece W are disposed on the lower mold, the cavity is formed in the upper mold, the mold is closed, and heating is performed to, for example, about 130° C. to 150° C., for compression molding. The lower mold is movable and the upper mold is fixed, but the lower mold may be fixed and the upper mold may be movable, or both molds may be movable. Here, the mold frame 11a is mold-opened and closed by a known mold opening and closing mechanism (not shown). For example, the mold opening and closing mechanism includes a pair of platens, a plurality of link mechanisms (tie bars and pillars) on which the pair of platens are erected, a drive source (for example, an electric motor) for moving (elevating) the platens, a drive transmission mechanism (for example, a toggle link), and the like (the drive mechanism is not shown).
In the mold frame 11a, a release film F is sucked and held on the surface of an upper mold clamp including the upper mold cavity. A film conveyance mechanism 11b is provided on the upper mold. For the release film F, an elongated continuous film material having excellent heat resistance, ease of peeling, flexibility, and extensibility is used, and for example, polytetrafluoroethylene (PTFE), polytetrafluoroethylene polymer (ETFE), PET, FEP, fluorine-impregnated glass cloth, polypropylene, polyvinylidene chloride, and the like are preferably used. The release film F is conveyed through the surface of the upper mold clamp from a feed roller F1 to a winding roller F2 in a winding manner. Here, instead of the elongated film, a strip-shaped film cut to a size required for a strip-shaped mold corresponding to the strip-shaped workpiece W may be used.
The workpiece W preheated to a predetermined temperature by the preheating part 10 is held by the loader 4, and loaded into the opened mold frame 11a. In this case, as will be described below, on the preheating stage 10b (workpiece alignment part), as will be described below, the workpiece W is pressed against a pair of X-axis reference blocks 10c and Y-axis reference blocks 10d with a pusher or the like, and thus the orientation of the workpiece W is adjusted to correct the positional displacement in the direction of rotation. After workpiece alignment is performed, the amount of displacement between the workpiece center position and the stage center position is detected from the amount of positional displacement between the external form position of the workpiece W and an alignment mark on the preheating stage 10b. If a dimensional tolerance of, for example, about ±1 mm is allowed with respect to the external form dimension of the workpiece W, a maximum difference of about 2 mm may occur. In addition, when the workpiece W is preheated to a certain temperature on the preheating stage 10b, the workpiece W is elongated. Here, elongation of the workpiece W due to preheating differs depending on the material of the carrier constituting the workpiece, and since the coefficient of linear expansion differs between various materials that are expected to be used such as resin materials constituting a so-called substrate, metal materials such as copper carriers, and glass (crystal) materials such as glass carriers, the amount of elongation of the workpiece W also differs. Therefore, before loading into the mold frame 11a, preferably, the workpiece holding position of the loader 4 can be corrected regardless of the material of the carrier K.
Here, in the present embodiment, the coordinates of the corner parts of the workpiece W are read by an imaging camera 4a included in the loader 4, the distance (amount of displacement with respect to the alignment mark) in the X-Y direction with respect to the positioning mark (alignment mark) indicating the reference position is calculated, the center position of the loader 4 is aligned with the center position of the workpiece W, and the workpiece W is then held. Here, since the workpiece
W draws a smile curve whose center is convex downward and tends to warp on the preheating stage 10b, the loader 4 presses the entire circumference of the workpiece W from the upper surface side with an annular pressing member (the frame 4b1: refer to
When the resin molding operation is completed, the mold frame 11a is opened, the loader 4 enters the frame, and the workpiece W is held and taken out. The workpiece W that is held by the loader 4 is conveyed to the cooling unit E by the press unit D, and delivered to a cooling stage 12 and cooled. The cooled workpiece W is subjected to a subsequent process (a dicing process, etc.). The movement range of the loader 4 in the X-Y direction is indicated by dashed arrows I and J shown in
Here, a configuration of the workpiece transfer part 2 will be described with reference to
On the holder plate 5, a positioning member for positioning the workpiece W based on the external form is provided. As an example, on the holder plate 5, a pair of positioning pins 5a for positioning the workpiece W at four corners are provided. The workpiece W is disposed on the upper surface of the holder plate 5 by aligning corners of the workpiece W formed in a rectangular shape between the positioning pins 5a.
Moreover, as shown in
As shown in
In
The above workpiece W preheated by the preheating part 10 and aligned is held on the preheating stage 10b by the loader 4 (loader hand mechanism) and conveyed to the mold frame 11a.
As shown in
As described above, the loader 4 suppresses the entire circumference of the workpiece W from the upper surface side to the annular frame 4b1 while the back side of the workpiece is supported by the chuck 4b2 (multi-point chuck) provided at a plurality of locations on one side of the workpiece W, and holds both surfaces of the workpiece in an insertion manner. As shown in
As shown in
As will be described below, an image processing unit 23 (refer to
Here, one imaging camera 4a is provided in the loader 4, but as shown in
Here, a control system of the compression molding device will be described with reference to a block configuration diagram centered on the preheating part 10 and the loader 4. The control unit 25 includes a CPU that controls operations of the compression molding device according to an input signal from a host controller and an input unit 26 such as an operation unit, a ROM in which a control program is stored, a RAM that reads the control program and is used for a work area of the CPU, the image processing unit 23 that reads coordinates from an image captured by the imaging camera 4a and calculates an amount of positional displacement, and the like. From the control unit 25, an output command is sent to the preheater 10a, the X-axis pusher 10g, the Y-axis pusher 10h, and the vacuum generating device 21 provided in the preheating part 10, and an output command is sent to the electro-pneumatic regulator 22, the X-Y servo mechanism 24 and the like provided in the loader 4, and operations of respective units are controlled.
Here, an example of a workpiece alignment operation using the preheating part 10 and the loader 4 will be described with reference to a flowchart shown in
When the loader 4 receives the workpiece W on which the resin R is mounted from the workpiece transfer part 2 at the delivery position Q on the workpiece delivery unit C shown in
When the loader 4 reaches the preheating stage 10b, the loader hand (LD hand) 4b descends and presses the workpiece W against the preheating stage 10b (Step S2). In this case, in order to correct deflection of the workpiece W and prevent a gap between it and the stage from being formed, the electro-pneumatic regulator 22 may perform control so that the pressing force of the frame 4b1 increases. This is to increase thermal conductivity of the workpiece W during preheating.
Next, the vacuum generating device 21 is started, adsorbs the workpiece W through the suction hole 10f of the preheating stage 10b and sucks it onto the preheating stage 10b, and the preheater 10a is started and preheats the workpiece W and the resin R to a predetermined temperature (for example, 100° C.) (Step S3: refer to
When the workpiece W and the resin R are preheated, suction is weakened (vacuum broken) by the vacuum generating device 21, as shown in
When the alignment operation of the workpiece W is completed, the vacuum generating device 21 is started again, adsorbs the workpiece W through the suction hole 10f of the preheating stage 10b and sucks it onto the preheating stage 10b, and the preheater 10a is started and preheats the workpiece W and the resin R to a predetermined temperature (for example, 100° C.) (Step S5).
Next, the imaging camera 4a mounted on the loader hand 4b moves the loader hand 4b in the X-axis direction and captures an external form image of the upper left corner of the workpiece W and an alignment mark image (Step S6: refer to
According to the amount of positional displacement of the workpiece W in the X-Y direction calculated by the image processing unit 23, the control unit 25 controls driving of the X-axis motor 24a and the Y-axis motor 24c according to the X-Y servo mechanism 24 via a motor driver (refer to
Then, the loader hand 4b descends onto the preheating stage 10b and suppresses the entire circumference of the workpiece W from the upper surface side with the annular frame 4b1 while the back side of the workpiece is supported by the chuck 4b2 (multi-point chuck) provided at a plurality of locations on one side of the workpiece W, and holds both surfaces of the workpiece in an insertion manner (refer to
With the above configuration, when the loader 4 (loader hand mechanism) holds the workpiece W aligned by the preheating part 10 (workpiece alignment part), since the center position of the loader hand 4b is aligned with the center position of the workpiece W and held according to the amount of positional displacement in the X-Y direction between the external form position of the workpiece W and the reference position (alignment mark), it is possible to hold the thin and large-size workpiece W without positional displacement.
Even if the workpiece W is preheated on the preheating stage 10b and the amount of warpage of the workpiece W differs, the flatness of the workpiece W can be maintained by changing the pressing force of the frame 4b1, and the external form size of the workpiece W can be accurately detected and the workpiece W can be accurately positioned and held while maintaining the flatness of the workpiece W with the loader hand 4b.
As the mold frame 11a of the present example, the upper mold cavity type has been described, but a lower mold cavity type mold frame may be used. In this case, the workpiece W may be mounted on the holder plate 5 with a surface on which an electronic component is mounted downward, and may be transferred by the workpiece transfer part 2.
In addition, the workpiece W is supplied to the upper mold by the loader 4 and the resin supply unit B may directly supply the mold resin R (granular resin or liquid resin) into the lower mold cavity by the dispenser and may supply the mold resin R that is disposed on the release film F.
In addition, the preheating part 10 has been exemplified as the workpiece alignment part and the loader 4 has been exemplified as the loader hand mechanism, but the present invention is not limited thereto, and the resin supply stage 7 on which the workpiece W is disposed, the pick and place mechanism 8 that picks up and conveys the workpiece W, and the like may be applied.
It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the present invention. In view of the foregoing, it is intended that the present invention covers modifications and variations provided that they fall within the scope of the following claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-089927 | May 2020 | JP | national |
