JP2004098602A - Resin molding apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin molding apparatus which enables reliable cleaning of a mold in a short time and which is excellent in production efficiency and has high reliability. <P>SOLUTION: The apparatus is equipped with a traveling head 14 which is so provided as to be movable between a top force and a bottom tool 12 in an opened state, a spray nozzle 16 which is fitted to the traveling head 14 and a spray material supply mechanism Sd which enables supply of a spray material containing a CO<SB>2</SB>component to the spray nozzle 16 on the traveling head 14. From the spray nozzle 16 made movable with the movement of the traveling head 14, dry ice particles are sprayed onto a prescribed place of the top or the bottom tool 12 so as to clean the place subjected to spray. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a resin molding apparatus for automatically charging and molding a tablet-shaped resin material into a mold.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been known a resin molding apparatus that includes an openable upper mold and a lower mold that constitute a mold, and injects and molds a resin material into a cavity formed by closing the upper mold and the lower mold.
[0003]
Softening the resin material in the pre-heated mold, press-fitting it into the cavity of the mold, and further heating and thermosetting the resin material to form the resin repeatedly according to the shape of the cavity Can be.
[0004]
Generally, a plurality of pots for accommodating a resin material are formed in a mold so that a plurality of resin moldings can be performed simultaneously.
[0005]
As such a resin molding apparatus, for example, a resin sealing apparatus that puts a sealed body such as a lead frame, a semiconductor substrate, a film, a tape, etc. together with a resin material into a mold and integrally molds the resin is used. It has been known.
[0006]
By the way, when the resin molding is repeatedly performed, a minute amount of resin (resin, additive material, residual material such as oil washing, etc.) adheres to the cavity of the mold, thereby causing a problem such as causing a trouble of a molded product. .
[0007]
For this reason, conventionally, a method has been generally adopted in which dirt in the cavity is adhered using a mold cleaning material such as an emic resin and the dirt is removed.
[0008]
[Problems to be solved by the invention]
However, this method has a problem that the ability to remove dirt is not always high. Therefore, when the amount of dirt that cannot be removed by this method increases, it is necessary to disassemble the mold, carefully clean each part using an abrasive, etc., and reassemble. Is the fact.
[0009]
However, as a practical problem, there has been a problem that disassembling and reassembling the mold of this type of resin molding apparatus requires an extremely long time and labor, and this stagnation greatly affects the productivity of the product. If the interval between disassembly and reassembly is increased to avoid this, there is a problem that the yield of products is reduced due to poor releasability.
[0010]
Incidentally, in relation to the present invention, the cleaning with an injection material comprising a CO ₂ component as a cleaning material, which are known per se.
[0011]
However, for example, a method in which a nozzle faces a cleaning surface of a mold by hand (see Japanese Patent Application Laid-Open No. H11-254454) generally requires a resin molding apparatus because the distance between an upper mold and a lower mold is narrow. Good cleaning cannot be performed unless it is disassembled and reassembled, and does not contribute to a reduction in time and labor.
[0012]
On the other hand, in the method in which the nozzle is made to face the cleaning surface of the mold from the outside of the resin molding apparatus using a robot, it is necessary to install the robot separately from the resin molding apparatus. The need to combine dedicated robots not only increases costs, but also complicates maintenance.
[0013]
The present invention has been made in view of such a conventional problem, and always maintains a good cleaning state of a cavity surface without disassembling a mold (or while greatly reducing the frequency of disassembly). It is an object of the present invention to provide a resin molding apparatus capable of achieving both labor saving and high yield (high productivity).
[0014]
[Means for Solving the Problems]
In a resin molding apparatus comprising an openable upper mold and a lower mold that constitute a mold, a resin material is poured into a cavity formed by closing the upper mold and the lower mold, and the upper mold is opened. Between the mold and the lower mold, a head installed so as to be relatively movable with respect to the upper and lower molds, attached to the head, and capable of facing a predetermined portion of the upper or lower mold. The object has been achieved by providing a cleaning injection nozzle and an injection material supply mechanism capable of supplying an injection material containing a CO ₂ component to the injection nozzle on the head.
[0015]
In the present invention, between the upper mold and the lower mold in the open state, a head installed so as to be relatively movable with respect to the upper mold and the lower mold, an ejection nozzle attached to the head, In contrast, a supply mechanism capable of supplying an injection material containing _two CО components is provided. As a result, the upper mold and the injection head which is freely displaceable along with the relative movement with respect to the lower mold of the head, as a possible cleaning by injection material including CO ₂ component to a predetermined position of the upper die or the lower die I have.
[0016]
As a result, the cleaning system is integrated into the resin molding apparatus, and inline cleaning can be performed. Therefore, the cost can be reduced, and the maintainability is remarkably improved.
[0017]
CO The injection material comprising _two components, may specifically employ a CO ₂ gas or liquefied CO ₂ pressurized to for example 3 to 8 MPa (more preferably 4~7MPa). These spray materials become dry ice particles (solid particles) by a nozzle, and can be sprayed at a predetermined pressure by the force of the supply pressure.
[0018]
The dry ice particles can be sprayed at a high speed together with a compressed gas (eg, argon gas or air), and high-level cleaning can be performed without disassembling the mold by using the gas wedge action of the cleaning principle. . In addition, since sublimation occurs after injection, there is no problem such as residual oil washing. In addition, since carbon dioxide produced as a result of sublimation has no toxicity, there is no need for strict recovery. Therefore, a safe environment can be maintained at low cost, and labor saving, improvement in yield, and maintenance of quality can be achieved.
[0019]
When the present invention is specifically implemented, for example, the injection nozzle is two-dimensionally movable within a predetermined plane between the upper mold and the lower mold in an open state, and has a predetermined interval. It is preferable to adopt a configuration in which the surface to be cleaned is exhaustively cleaned by enabling the scanning and cleaning.
[0020]
In this case, instead of cleaning the entire surface of the cleaning surface each time molding is performed, only a part of the surface to be cleaned is operated and cleaned in one molding, and the cleaning should be performed through a plurality of moldings. It is preferable that the entire surface is scanned and cleaned (described later).
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0022]
FIG. 1 is a schematic perspective view showing the overall structure of a resin molding device 10 according to the present embodiment. FIG. 1 shows a state in which the mold of the resin molding apparatus 10 is opened, and the display of the upper mold is omitted.
[0023]
The resin molding apparatus 10 includes an openable and closable upper mold and a lower mold 12 constituting a mold, and a resin material is poured into a cavity 13 formed by closing the upper mold and the lower mold 12 to perform molding. The basic configuration itself is not particularly different from the conventional one, and the same configuration is employed. Reference numeral 12A denotes a chase that allows a part of the lower mold 12 to be replaced.
[0024]
The resin molding apparatus 10 further includes a traveling head 14 movably installed between the upper mold and the lower mold in an open state, an injection nozzle 16 attached to the traveling head 14, An injection material supply mechanism Sd that can supply an injection material containing _two CО components to the upper injection nozzle 16 is provided.
[0025]
The traveling head 14 includes a cam follower 20 that engages with the groove 18A of the guide rail 18, and can be moved in the front-rear direction (X direction in the figure) along the guide rail 18 by driving means (not shown). .
[0026]
The traveling head 14 includes a cleaner brush 22 and a ball screw 26. The cleaner brush 22 is rotatable by a motor (not shown), and the ball screw 26 is rotatable by a motor 24. A nut support portion 28 is screwed to the ball screw 26 so as to be non-rotatable and slidable, and the nut support portion 28 can move in the left-right direction (Y direction in the drawing) with the rotation of the ball screw 26. ing. The dry ice spray nozzle 16 is attached to the nut support portion 28, and can be moved in the left-right direction integrally with the nut support portion 28. As a result, the surface of the chase 12A to be cleaned is Left and right two-dimensional movement is possible.
[0027]
The injection material supply mechanism Sd includes a CO ₂ cylinder 30 containing a C ₂ gas or a liquefied C ₂ (a spray material containing C ₂ components) pressurized to 4 to 7 MPa and a control box 32. By forming a state similar to so-called adiabatic expansion when injected, the injection nozzle 16 can inject as dry ice particles of a predetermined pressure. As described above, the dry ice particles are injected together with the compressed gas depending on the application. The present invention also includes a device which is provided with a mixed injection material supply mechanism (not shown) that can supply, for example, argon gas or air to the injection nozzle, and injects the argon gas or air in combination. .
[0028]
Incidentally, the mixed injection material feeding mechanism in this case is provided in parallel with the injection material feeding mechanism Sd containing CO ₂ component injection material supply through a valve (not shown) upstream of the injection nozzle 16 containing the CO ₂ component It merges with the system of the mechanism Sd.
[0029]
Next, the operation of the resin molding apparatus 10 will be described.
[0030]
After the resin is sealed, when the mold is opened and the upper mold and the lower mold 12 are separated from each other, the sealed lead frame and the like are transported by another unit. Thereafter, the traveling head 14 moves forward while being guided by the guide rails 18 to clean the residue on the chase 12A (the locus in FIG. 2A). At this time, dry ice particles are ejected onto the chase 12A from the tip of the ejection nozzle 16 attached to the nut support 28 at the tip of the traveling head 14. The residue separated from the chase 12A by this injection is sucked and cleaned by the cleaner brush 22.
[0031]
The traveling head 14 advances to a position where the cleaner brush 22 reaches the tip of the chase 12A, where the motor 24 of the ball screw 26 is driven, and the injection nozzle 16 is moved slightly rightward with the movement of the nut support 28 ( The locus in FIG. 2B). Then, the cleaner head 14 starts retreating (the locus of c in FIG. 2), and stops the injection from the injection nozzle 16 to wait for the next press (sealing) at the fully retracted position. If the press cycle is short, or if a more stable injection is intended, the injection from the injection nozzle 16 may be stopped without stopping (as it is being injected).
[0032]
After the next press is completed, cleaning on the chase 12A is performed in exactly the same steps along the trajectories indicated by reference numerals d, e, f, and g in FIG. Thereafter, in one press, the cleaning trajectories h, i, j, k... Sequentially proceed rightward, and when they reach the end of the chase 12A, the trajectories a, b, c → ( (Standby: press) → trajectories d, e, f, g → (standby: press) → trajectories h, i, j, k...
[0033]
Note that completely the same cleaning is performed on the upper mold (not shown) at the same time.
[0034]
Further, as is apparent from the above structure, cleaning by the cleaning brush 22 is performed every time the traveling head 14 reciprocates in the front-rear direction.
[0035]
As described above, the entire surface to be cleaned is not subjected to dry ice cleaning for each press. 1) When cleaning by dry ice injection is performed, the cleaning head 14 is advanced to some extent at a low speed. Otherwise, the adhered residue may not be peeled off. However, if dry ice is sprayed on the entire surface to be cleaned at a low speed for each press, the cleaning time becomes extremely long. That is, 2) the total amount of adhesion of the residue is not so large by one press, and therefore, it is not necessary to always perform cleaning by dry ice injection every time.
[0036]
Therefore, in this embodiment, only a part of the surface to be cleaned is reliably cleaned at a relatively low speed every time one press is performed, and as a result, the entire cleaning surface is cleaned once every several presses. You.
[0037]
The structure for specifically moving (displacing or scanning) the ejection nozzle is not limited to the above-described structure. For example, in the above-described embodiment, the traveling head 14 itself can be moved back and forth, and the nut support portion 28 that supports the nozzle on the traveling head 14 can be moved left and right. It may be configured to be movable left and right. In this case, it can be seen that the “support” supporting the ejection nozzle constitutes the head.
[0038]
When the traveling head 14 is moved by a combination of the forward and backward movement and the left and right movement as in the present embodiment, when the forward and backward movement and the left and right movement distance of the traveling head 14 are changed, the change amount is set to a numerical value. By providing an input device for inputting in the above, readjustment when changing the size of the chase 12A can be easily performed.
[0039]
Further, when a sensor for detecting the shape of the chase 12A is provided, the movement control of the traveling head 14 and the on / off control of the injection nozzle 16 can be performed in conjunction with the detection signal.
[0040]
Further, it is also possible to configure the patterns of the chase 12A in advance, and to control the movement of the traveling head 14 according to the pattern and the movement distance designated when the chase 12A is changed.
[0041]
As described above, if an automatic control device having a change input device, a shape detector, a pattern setting device, a computing device and the like is provided, efficient online cleaning can be achieved.
[0042]
These advantages are achieved by adopting a configuration in which the injection nozzle can be two-dimensionally moved within a predetermined plane between the upper die and the lower die as in the present embodiment, and the surface to be cleaned can be exhaustively scanned. This is particularly effective when the operation is performed, and can be realized without a large increase in cost.
[0043]
On the other hand, it is not always necessary to perform the cleaning in the above-described steps. For example, the traveling head 14 may be moved back and forth for at least two reciprocations for each press, or the traveling head 14 is finally moved so that the cleaning by the cleaning brush 22 is always performed after the ejection of the dry ice particles. When retreating, it is also possible not to perform the injection of dry ice. Of course, depending on the type of the chase, a three-pronged nozzle or a four-pronged nozzle may be used to perform dry ice cleaning on the entire surface to be cleaned at one time for each press. Dry ice cleaning may be partially performed every several presses.
[0044]
In the above-described embodiment, the mold is fixed and the injection nozzle is controlled to move. However, on the contrary, the injection nozzle may be fixed and the mold is controlled to move so that the two can be relatively moved. .
[0045]
Further, in addition to the above-described configuration, for example, a vacuum suction mechanism may be further provided in parallel to efficiently suck and collect a residue separated from the cleaning surface by the injection of dry ice.
[0046]
FIG. 3 shows an example of a design change of the tip structure of the injection nozzle 60 which realizes suction of the residual matter by the vacuum.
[0047]
The injection nozzle 60 not only enables dry ice particles (or a mixture thereof with a compressed gas such as argon gas) to be injected from a central injection port 62, but also places a predetermined distance L around the periphery thereof. The vacuum suction port 64 faces coaxially in an integrated state.
[0048]
By employing the injection nozzle 60 having such a structure, the residue separated from the surface of the chase 12A by the injection of the dry ice particles can be reliably collected without diffusing with the surrounding air Ar. Become.
[0049]
Incidentally, the vacuum suction structure or including cleaning structure by the cleaning brush, for either the present invention features a what cleaning mechanism in addition to the cleaning mechanism due to the injection material including CO ₂ component is not particularly limited.
[0050]
【The invention's effect】
As described above, according to the present invention, the cavity surface is always maintained in a good cleaning state without disassembling the mold (or while greatly reducing the frequency of disassembly), thereby saving labor and increasing yield (high yield). (Productivity) can be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a mold of a resin molding apparatus according to an embodiment of the present invention is opened. FIG. 2 is a perspective view showing a cleaning trajectory in the resin molding apparatus when viewed from a plane direction. Enlarged sectional view of the nozzle tip showing an example of nozzle design change
DESCRIPTION OF SYMBOLS 10 ... Resin molding apparatus 12 ... Lower mold (of a metal mold) 14 ... Running head 16, 60 ... Injection nozzle 18 ... Guide rail 20 ... Cam follower 22 ... Cleaner brush 24 ... Motor 26 ... Ball screw 28 ... Nut support part 30 ... CO ₂ cylinders 32: control box Sd: injection material supply mechanism

Claims (5)

In a resin molding apparatus comprising an openable upper mold and a lower mold that constitute a mold, and casting and molding a resin material into a cavity formed by closing the upper mold and the lower mold,
Between the upper mold and the lower mold in the open state, a head installed movably relative to the upper and lower molds,
A cleaning spray nozzle attached to the head and capable of facing a predetermined portion of the upper mold or the lower mold,
An injection material supply mechanism for supplying an injection material containing a CO ₂ component to an injection nozzle on the head. In claim 1,
The injection material supply mechanism supplies CO ₂ gas or liquefied C 化₂ pressurized to 3 to 8 MPa as the injection material to the injection nozzle,
The injection molding nozzle injects the injection material as dry ice particles to a predetermined portion of the upper die or the lower die. In claim 2,
Further provided with a mixed injection material supply mechanism capable of supplying argon gas or air to the injection nozzle,
A resin molding apparatus, wherein the dry ice particles can be injected together with argon gas or air from the injection head. In any one of claims 1 to 3,
The spray nozzle is two-dimensionally movable relative to the upper mold and the lower mold in a predetermined plane between the upper mold and the lower mold in an open state, and is capable of scanning at a predetermined interval. By doing
A resin molding apparatus capable of comprehensively cleaning a surface to be cleaned. In claim 4,
A resin characterized in that only a part of the surface to be cleaned can be scanned and cleaned each time molding is performed, and the entire surface to be cleaned is scanned and cleaned through a plurality of moldings. Molding equipment.

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