JP6084599B2 - Molding method and molding apparatus for molding a plurality of molded products in parallel - Google Patents

Description

  The present invention uses a plurality of sets of mold units that are slidable between an injection position where the mold can be opened and closed and the molten resin can be injected, and a retreat position where the mold closing is maintained while being self-held, A molding method in which the mold unit is slid one by one to the injection position, clamped and injected, slid to the retracted position to cool the resin, and when slid again to the injection position, the mold is opened and the molded product is taken out, and The present invention relates to a molding apparatus that performs the molding method.

As is well known in the art, an injection molding machine includes an injection device for injecting molten resin, a mold clamping device for clamping a mold, and the like. When the mold is clamped by the mold clamping device and the molten resin is injected from the injection device, the molten resin is filled in a cavity formed in the mold. When the mold is opened by driving the mold clamping device after the resin is cooled and solidified, a molded product is obtained. By the way, the time required for cooling and solidifying the resin differs depending on the molded product. When the molded product is thick, it takes a long time. Therefore, when molding a thick molded product, it is necessary to ensure a sufficient time to wait for cooling and solidification. Since the mold cannot be opened and closed during this cooling and solidification, other processes such as injection cannot be performed. Accordingly, the entire molding cycle becomes longer, and the productivity of the injection molding machine is reduced.

JP-A-6-114874 JP 7-186176 A

  In Patent Documents 1 and 2, there is an injection molding method that can mold two molded products in parallel by using two sets of mold units composed of a set of molds that can self-hold the mold closed state. Have been described. The molding methods described in these documents are known as a so-called OCI molding method, that is, an OUT COOLING INJECTION method, and use a mold unit having a predetermined structure. More specifically, the mold unit is composed of a movable mold and a fixed mold, and the movable mold is fixedly provided on a slide plate that slides on the movable plate, and is parallel to the movable plate by the slide plate. Although it is slid, it is not separated from the movable platen. On the other hand, the fixed mold is detachable from the fixed plate by a predetermined fixing means. These movable molds and fixed molds can be self-held in a mold-clamped state, that is, a mold-closed state, by a predetermined locking means.

  In the OCI molding method, a plurality of sets of such mold units are used, but an OCI molding method using two sets of mold units will be described. First, the movable molds of the two sets of mold units that are locked so that the mold is closed are fixed to the slide disk. No fixed mold is fixed to the fixed platen. The slide plate is driven to slide one mold unit to the injection position. When the mold clamping device is driven and the mold is clamped, the fixed mold of the mold unit comes into contact with the fixed platen. The fixing means is operated to fix the fixed mold to the fixed plate and perform injection. When the fixing means is released after injection and the mold is opened in the locked state, the mold unit is held in its closed state and is maintained in that state. The slide plate is driven to slide the other mold unit to the injection position. Then, one mold unit is slid to the retracted position, and the injected resin is cooled and solidified. When the mold clamping device is driven and the mold is clamped, the stationary mold and the stationary platen of the other mold unit come into contact with each other. The fixing means is operated to fix the fixed mold to the fixed plate and perform injection. When the fixing means is released after injection and the mold is opened in the locked state, the mold unit is held in a closed state. The slide plate is driven to slide one mold unit to the injection position. Then, the other mold unit is slid to the retracted position, and the injected resin is cooled and solidified. In one mold unit, the resin is sufficiently cooled and solidified. When the mold clamping device is driven to close the mold, the fixed mold of one mold unit comes into contact with the fixed platen. The fixing means is actuated to fix the fixed mold to the fixed plate and release the locking means. When the mold clamping device is driven to open the mold, one mold unit is opened to obtain a molded product. After the molded product is taken out, the mold clamping device is driven to clamp one mold unit and inject molten resin. After injection, the fixing means is released, the locking means is activated, and the mold is opened. If it does so, one mold unit will self-hold the mold closed state. The slide plate is driven to slide the other mold unit to the injection position and one mold unit to the retracted position. Thereafter, molding is performed in the same manner. When molding is performed in this way, when injection molding is performed in one mold unit, cooling and solidification can be performed in the other mold unit. Then, two molded articles are molded substantially in parallel. By implementing the OCI molding method, even a thick molded product that requires time for cooling and solidification can be molded in a short molding cycle, and the productivity of the injection molding machine can be increased.

  By the way, it is not intended to improve the productivity of injection molding machines, but it is a so-called heat method as a molding method for obtaining molded products with excellent surface transfer properties such as glossy molded products and molded products having fine shapes. Andcool molding methods are well known. The heat and cool molding method is a molding method in which a molten resin is injected while a mold is heated, and then the mold is cooled to obtain a molded product. The molten resin injected into the mold cavity has a high mold temperature, and maintains a high fluidity without cooling and solidifying, and smoothly flows along the surface of the cavity. Since the molten resin is then cooled in a state where the molten resin is properly filled in the cavity, a molded product having excellent surface transferability can be obtained.

  When a molded product is obtained by injection molding, it is necessary to secure time for cooling and solidifying the injected resin. As described above, in the conventional injection molding method, when cooling and solidifying, other processes cannot be performed, so the productivity of the injection molding machine is lowered, particularly when molding a thick molded product. It is remarkable. On the other hand, in the case of molding by the OCI molding method, the molten resin can be injected in the other mold unit when cooling and solidifying is performed in one mold unit, so that the productivity of the injection molding machine is high. Are better. However, although it is excellent in productivity as described above, there should be room for further improvement in productivity. Further, the OCI molding method is not a method for improving the quality of a molded product to be molded, but there should be room for improvement in order to obtain a high-quality molded product with high surface transferability. In order to obtain such a high-quality molded article, it seems to be good to carry out the heat and cool molding method as described above, but in order to heat and cool the mold for each of the mold units in each group If the temperature control device is prepared, the cost increases and the device becomes large.

  An object of the present invention is to provide a molding method that solves the above-described problems. Specifically, even a thick molded product can be molded with high productivity, and a molded product obtained. An object of the present invention is to provide a molding method with high quality and low cost, and a molding apparatus for performing such a molding method.

In order to achieve the object of the present invention, the present invention is directed to a so-called OCI molding method and is configured as a modified method. In other words, when a plurality of sets of mold units are slid to the injection position where the mold can be opened and closed and the retreat position where the mold is closed while being held in a self-held state, if any one set is slid to the injection position, the other set Uses a plurality of sets of mold units that are designed to slide to the retreat position, and then performs an injection process in which the mold unit is clamped and injected at the injection position, and the injected mold unit is slid to the retreat position. A molding cycle consisting of a cooling process for cooling the resin and a take-out process of sliding the cooled mold unit to the injection position and opening the mold to take out the molded product is performed in parallel in a plurality of mold units. The object is a molding method in which a plurality of molded products are molded in parallel. In this OCI molding method, one temperature adjusting device provided with a valve unit is used. Then, a heating heat medium is supplied to the mold unit that controls the valve unit to perform the injection process to heat the mold unit, and a cooling heat medium is supplied to the mold unit that performs the cooling process. The mold unit is configured to be cooled.

Thus, in order to achieve the above object, the invention according to claim 1 includes a plurality of mold units having an injection position at which the mold can be opened and closed and a retreat position at which the mold closed state is retreated in a self-held state. When one set is slid to the injection position and the other set is slid to the retracted position, the plurality of sets of mold units are used to move the mold unit to the injection position. An injection process in which the mold is clamped and injected, a cooling process in which the injected mold unit is slid to the retracted position to cool the resin, and the cooled mold unit is slid to the injection position to mold In a molding method of forming a plurality of molded products in parallel by performing a molding cycle including an extraction step of opening and taking out a molded product in parallel in the plurality of mold units. It uses a single temperature adjustment device provided with a valve unit, wherein the said mold unit the valve unit is controlled to implement the injection process by supplying heated heat medium heating the mold unit The mold unit for performing the cooling step is configured as a molding method for molding a plurality of molded products in parallel, wherein a cooling heat medium is supplied to the mold unit to cool the mold unit. The
A second aspect of the present invention is the molding method according to the first aspect, wherein the mold unit is composed of two sets, and is configured as a molding method for molding two molded products in parallel. .

The invention according to claim 3 is a molding apparatus including a plurality of sets of mold units and one temperature adjustment device, wherein the mold unit has an injection position and a resin for injecting molten resin. The mold is slid to the retreat position to be cooled, the mold can be opened and closed at the injection position, and the mold closed state is self-held at the retreat position. When one set is slid to the injection position, the other set is slid to the retracted position, the temperature adjusting device includes a valve unit, and the plurality of mold units include the valve unit. The heating heat medium and the cooling heat medium are switched and supplied via the, and is configured as a molding apparatus for molding a plurality of molded products in parallel.
According to a fourth aspect of the present invention, in the molding apparatus according to the third aspect, the mold unit is composed of two sets, and is configured as a molding apparatus that molds two molded products in parallel. .

As described above, the present invention uses a plurality of mold units, performs a molding cycle in parallel in these plurality of mold units, and molds a plurality of molded products in parallel. That is, a so-called OCI molding method is targeted. In the OCI molding method, a molding cycle executed in one set of mold units includes an injection process in which the mold unit is clamped and injected at the injection position, and the injected mold unit is slid to the retracted position to transfer the resin. The cooling process includes a cooling process, and a cooled mold unit is slid to an injection position and opened to take out a molded product. According to the present invention, in such an OCI molding method, a heating medium is supplied to a mold unit that controls a valve unit and performs an injection process using a single temperature adjusting device equipped with the valve unit. Then, the mold unit is heated, and a cooling heat medium is supplied to the mold unit that performs the cooling process to cool the mold unit. That is, the present invention is configured as a molding method in which a so-called heat and cool molding method is combined with an OCI molding method. Therefore, the obtained molded product is excellent in surface transferability and is guaranteed to be of high quality. Moreover, since it can cool in a short time in a cooling process, productivity of an injection molding machine improves further. Furthermore, according to the present invention, the heating heat medium and the cooling heat medium are supplied so as to be switched using a single temperature adjusting device, so that the temperature adjusting device can be shared by a plurality of sets of mold units. There is no need to prepare for each unit. This can reduce the cost of the apparatus.

It is a front view which shows a partial cross section of the shaping | molding apparatus which concerns on embodiment of this invention. The figure explaining each process which shape | molds two molded articles in parallel with the shaping | molding method which concerns on embodiment of this invention using the shaping | molding apparatus which concerns on embodiment of this invention, The (a)-( F) is a front view of the molding apparatus in each step. The figure explaining each process which shape | molds two molded articles in parallel with the shaping | molding method which concerns on embodiment of this invention using the shaping | molding apparatus which concerns on embodiment of this invention, The (a)-( F) is a front view of the molding apparatus in each step.

  Embodiments of the present invention will be described. The molding apparatus 1 according to the present embodiment includes an injection molding machine, two sets of mold units 8 and 9 having predetermined characteristics, and one temperature adjustment apparatus 2. Although only a part of the injection molding machine is shown in FIG. 1, the injection molding machine is configured as known in the art, and includes a mold clamping device 3 for clamping a mold, an injection device 4 for injecting molten resin, a projection device, and the like. It is composed of As is well known in the art, the mold clamping device 3 is also composed of a fixed platen 5, a movable platen 6 and a mold clamping mechanism (not shown) for opening and closing them.

  In the molding apparatus 1 according to the present embodiment, the mold clamping apparatus 3 is provided with first and second mold units 8 and 9. The mold units 8 and 9 are respectively composed of movable molds 11 and 12 attached to the movable platen 6 and fixed molds 13 and 14 attached to the fixed platen 5, and are necessary for carrying out a so-called OCI molding method. It has the following two features. First, the first feature is that these mold units 8 and 9 or the movable molds 11 and 12 slide on the movable platen 6. These movable molds 11 and 12 are attached to a slide board 15 provided on the movable board 6. The slide plate 15 slides on the movable plate 6 along the movable plate 6 by a predetermined drive mechanism, in this embodiment, the piston cylinder unit 16. Since it is configured in this manner, the two sets of mold units 8 and 9 can be alternately slid to the injection position and the retracted position as will be described later.

  The second feature of the mold units 8 and 9 is that they include lock mechanisms 18 and 19 and fixing mechanisms 21 and 22. Since the structures of the lock mechanisms 18 and 19 and the fixing mechanisms 21 and 22 are described in detail in, for example, Patent Document 1, a specific structure will not be described in this specification, but the following functions are provided. Yes. First, when the movable molds 11 and 12 and the fixed molds 13 and 14 are in the mold-closed state, the lock mechanisms 18 and 19 lock each other so that the mold-closed state is self-held. It can be canceled. The fixing mechanisms 21 and 22 can fix the fixed molds 13 and 14 to the fixed platen 5 or release the fixing. More precisely, in the present embodiment, the mounting plate 24 is fixed to the fixed plate 5, and the fixed molds 13 and 14 are fixed to the mounting plate 24 by the fixing mechanisms 21 and 22. Is released and separated.

The injection device 4 includes a heating cylinder 26 and a screw (not shown) as is well known, and an injection nozzle 27 is provided at the tip of the heating cylinder 26. The fixed platen 5 and the mounting plate 24 are cut out, and the injection nozzle 27 of the injection device 4 is inserted into the cutout. In FIG. 1, the injection nozzle 27 is shown in contact with the sprue of the fixed mold 13 of the first mold unit 8.

  The temperature adjusting device 2 includes a high-temperature tank 29 that stores a heating heat medium maintained at a predetermined high temperature, and a low-temperature tank 30 that stores a cooling heat medium maintained at a predetermined low temperature. , 9 can be supplied with a heating medium to heat the mold units 8, 9, or a cooling heat medium can be supplied to cool the mold units 8, 9. In the present embodiment, the temperature adjustment device 2 includes a valve unit 32 that switches a heat medium conduit, thereby enabling the mold units 8 and 9 to switch between a heating heat medium and a cooling heat medium. It can be supplied. In the molding apparatus 1 according to the present embodiment, the valve unit 32 of the temperature adjustment apparatus 2 is controlled by a command from the controller of the injection molding machine. Accordingly, when the OCI molding method is performed in the injection molding machine, the heating unit or the heating unit can be switched to be supplied to the desired mold units 8 and 9 by operating the valve unit 32 in synchronization with the molding process. .

  The injection position and the retracted position will be described. In the molding apparatus 1 according to the present embodiment, the first mold unit 8 and the second mold unit 9 are slid by the piston cylinder unit 16 and can alternately take the injection position and the retreat position. It is like that. The injection position is a position aligned with the injection device 4 so that injection can be performed and the mold units 8 and 9 can be opened and closed. On the other hand, the retracted position is a position that is not aligned with the injection device 4, and the mold units 8 and 9 are held by the lock mechanisms 18 and 19 in a closed state. That is, the mold units 8 and 9 are in a position where the mold is not opened and closed. The resin injected into the mold is cooled at the retracted position.

The molding method according to the present embodiment will be described with reference to FIGS. First, as shown in FIG. 2A, the first mold unit 8 is aligned with the injection position, and the fixed mold 13 is attached to the mounting plate 24 of the fixed platen 5 by the fixing mechanism 21. The first mold unit 8 will be described in a state where the first mold unit 8 is opened. The mold clamping device 3 is driven. Then, the movable platen 6 is driven in the direction of the fixed platen 5 and the first mold unit 8 is closed, that is, clamped, as shown in FIG. The lock mechanism 18 is operated to lock the dies 11 and 13. Prior to the injection process, the valve unit 32 is controlled to supply a heating medium from the temperature adjusting device 2 to heat the first mold unit 8 as indicated by the symbol H. When the first mold unit 8 reaches a desired temperature, the injection apparatus 4 is driven to inject the molten resin as shown in FIG. The cavity of the first mold unit 8 is filled with resin. The injection process is complete. As indicated by the symbol N in FIG. 2D, the valve unit 32 is controlled to stop the supply of the heating heat medium to the first mold unit 8. Then, the fixing mechanism 21 is released and the mold clamping device 3 is driven to open the mold. Then, as shown in FIG. 2D, the first mold unit 8 is separated from the fixed platen 5.

The piston cylinder unit 16 is driven to slide the first mold unit 8 to the retracted position and the second mold unit 9 to the injection position as shown in FIG. The valve unit 32 is controlled to supply a cooling heat medium to the first mold unit 8 to start cooling the first mold unit 8 as indicated by reference numeral C. In the first mold unit 8, a cooling process in which the molten resin is cooled and solidified after the injection process is completed is started. In this way, in the cooling process, by supplying the cooling heat medium and forcibly cooling, the time required for cooling is shortened. In parallel with such a cooling process, the injection process is performed in the second mold unit 9 as follows. First, the mold clamping device 3 is driven to close the mold. Then, as shown in FIG. 2F, the fixed mold 14 of the second mold unit 9 comes into contact with the mounting plate 24 of the fixed platen 5. The fixing mechanism 22 is operated to fix the fixed mold 14 to the mounting board 24. A heating medium is supplied to the second mold unit 9 by controlling the valve unit 32. When the second mold unit 9 reaches a desired temperature, the injection device 4 is driven to inject the molten resin, as shown in FIG. The cavity of the second mold unit 9 is filled with resin. The injection process is complete. The valve unit 32 is controlled to stop the supply of the heating heat medium to the second mold unit 9. In the second mold unit 9, the cooling process is started. The fixing mechanism 22 is released and the mold clamping device 3 is driven to open the mold. Then, the second mold unit 9 is separated from the stationary platen 5 as shown in FIG.

  The piston cylinder unit 16 is driven to slide the first mold unit 8 to the injection position and the second mold unit 9 to the retracted position as shown in FIG. The valve unit 32 is controlled to supply a cooling heat medium to the second mold unit 9 to forcibly cool the second mold unit 8 as indicated by symbol C, and the symbol N The supply of the heat medium to the first mold unit 8 is stopped as shown in FIG. The cooling process of the first mold unit 8 is completed. Since the first mold unit 8 was performing the cooling process in parallel with the second mold unit 9 while performing the injection process, the injected resin was sufficiently cooled and solidified. doing.

  The mold clamping device 3 is driven to close the mold. Then, as shown in FIG. 3D, the fixed mold 13 of the first mold unit 8 comes into contact with the mounting plate 24 of the fixed platen 5. The fixing mechanism 21 is operated to fix the fixed mold 13 to the mounting board 24. When the lock mechanism 18 is released and the mold clamping device 3 is driven to open the mold, the first mold unit 8 is opened as shown in FIG. A protrusion device (not shown) is driven. That is, an extraction process is performed. A molded product S is obtained.

  Subsequent to the take-out process, an injection process is performed by the first mold unit 8. That is, as shown in FIG. 3F, the mold clamping device 3 is driven to close the mold, the fixing mechanism 21 is operated to fix the fixed mold 13 to the mounting plate 24, and the lock mechanism 18 is It operates to lock the first mold unit 8 in the mold closed state. When the valve unit 32 is controlled and a heating medium is supplied to the first mold unit 8 as indicated by symbol H, and the first mold unit 8 reaches a desired temperature, the injection is performed. The apparatus 4 is driven to inject molten resin. The injection process is complete. If molding is performed in the same manner, molding cycles can be performed in parallel in the first and second mold units 8 and 9, and two molded products can be molded in parallel.

DESCRIPTION OF SYMBOLS 1 Molding apparatus 2 Temperature control apparatus 3 Mold clamping apparatus 4 Injection apparatus 5 Fixed board 6 Movable board 8 1st mold unit 9 2nd mold unit 11, 12 Movable mold 13, 14 Fixed mold 15 Slide board 16 Piston cylinder unit 18, 19 Lock mechanism 21, 22 Fixing mechanism 24 Mounting board 26 Heating cylinder 27 Injection nozzle 29 High temperature tank 30 Low temperature tank 32 Valve unit

Claims (4)

When a plurality of sets of mold units are slid to an injection position where the mold can be opened / closed and a retreat position where the mold closed state is retracted in a state where the mold closed state is self-held, when any one set is slid to the injection position, Using the plurality of sets of mold units adapted to slide to the retracted position,
An injection step of clamping and injecting the mold unit at the injection position; a cooling step of cooling the resin by sliding the injected mold unit to the retracted position; and the cooled mold unit. Forming a plurality of molded products in parallel by carrying out a molding cycle consisting of a take-out step of taking out a molded product by sliding to the injection position and opening the mold to take out the molded product. In the molding method to
Using a single temperature adjusting device equipped with a valve unit, the mold unit that controls the valve unit to perform the injection process is supplied with a heating heat medium to heat the mold unit. A molding method for molding a plurality of molded products in parallel, wherein a cooling heat medium is supplied to the mold unit for performing the cooling step to cool the mold unit.   The molding method according to claim 1, wherein the mold unit is composed of two sets, and two molded products are molded in parallel. A molding apparatus comprising a plurality of sets of mold units and one temperature adjustment device,
The mold unit is slid between an injection position where the molten resin is injected and a retracted position where the resin is cooled. The mold unit can be opened and closed at the injection position, and the mold closed state is self-held at the retracted position. And when any one of the plurality of mold units is slid to the injection position, the other set is slid to the retracted position.
The temperature adjusting device includes a valve unit, and a heating heat medium and a cooling heat medium are switched and supplied to the plurality of sets of mold units via the valve unit. A molding apparatus that molds a plurality of molded products in parallel.   The molding apparatus according to claim 3, wherein the mold unit is composed of two sets, and moldings two molded products in parallel.

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