JP3583076B2 - Injection molding method and injection molding machine - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an injection molding method and an injection molding machine suitable for use in molding a composite molded article.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as an injection molding machine for molding a composite molded article, an injection molding machine disclosed in Japanese Patent Application Laid-Open No. H10-113396 proposed by the present applicant has already been known.
[0003]
This injection molding machine has a primary mold for molding the primary molded body and a secondary mold for molding the secondary molded body, and the movable mold of the primary mold and the secondary mold is interchangeable. Equipped with a closed mold clamping device. Thereby, after the primary molded body is primarily molded by the primary mold, the movable molds of the primary mold and the secondary mold are exchanged with each other, and thereafter, the primary molded body is secondarily molded by the secondary mold. A composite molded article can be obtained.
[0004]
By the way, in such an injection molding machine, a composite molded product in which a secondary molding resin is added to one surface of a primary molded body molded with a primary molding resin, such as a laminated structure, can be relatively easily molded. However, as shown in FIGS. 8 and 9, it is not easy to mold a composite molded article A in which a part Afp of the primary molded article Af is wrapped. , The primary molded body molded with the primary mold is once removed from the primary mold by a molded product take-out machine, etc., and then set in a separate secondary mold, and insert molding is performed with this secondary mold. I was In FIGS. 8 and 9, As indicates a secondary molded portion molded with the secondary molding resin.
[0005]
[Problems to be solved by the invention]
However, such a conventional injection molding machine (injection molding method) has the following problems.
[0006]
First, since a separate molded product take-out machine or the like is required, the cost of the molding equipment is significantly increased, and the size of the equipment is inferior in space saving.
[0007]
Secondly, it is necessary to take out the primary molded product from the primary die once and then transfer it to a separate secondary die, so that the molding cycle becomes longer and the production efficiency cannot be increased.
[0008]
The present invention has solved the problems existing in such conventional technology, and can achieve a large cost reduction and downsizing (space saving) of molding equipment when molding a composite molded article, and a molding cycle. It is an object of the present invention to provide an injection molding method and an injection molding machine capable of dramatically increasing production efficiency by shortening the production time.
[0009]
Means and Embodiments for Solving the Problems
The injection molding method according to the present invention includes a primary mold part 2x for molding the primary molded body Af and a secondary mold part 2y for molding the secondary molded body A, and the primary molded body Af is formed by the primary mold part 2x. After the primary molding, the movable mold 2xm having the primary molded body Af located at the primary mold part 2x and the movable mold 2ym located at the secondary mold part 2y are exchanged, and the primary molded body is moved by the secondary mold part 2y. When the secondary molded body A enclosing a part Afp of Af is secondary molded, the primary molding cavities Cxx, Cyx are provided in the concave portions 3x, 3y provided on the parting surfaces Sx, Sy of the movable dies 2xm, 2ym. And the core blocks 4x and 4y that can be selectively displaced to the first position Pa and the second position Pb in the plane direction Fs provided with the secondary molding cavities Cxy and Cyy, respectively, and the core blocks in the primary mold part 2x. 4x (4y) first Is displaced to Pa performs primary molding, characterized in that to perform the secondary molding core block 4y (4x) is displaced to a second position Pb in the secondary mold portion 2y.
[0010]
Further, the injection molding machine 1 according to the present invention has a primary mold part 2x for molding the primary molded body Af, and a secondary mold part 2y for molding the secondary molded body A. In an injection molding machine provided with a mold clamping device configured so that the movable mold 2xm located therein and the movable mold 2ym located in the secondary mold part 2y can be exchanged, a concave portion 3x is formed in the parting surface Sx, Sy of each movable mold 2xm, 2ym. , 3y, and can be selectively displaced in the concave portions 3x, 3y to a first position Pa and a second position Pb in the plane direction Fs in which the primary molding cavities Cxx, Cyx and the secondary molding cavities Cxy, Cyy are provided. Each of the core blocks 4x and 4y is accommodated, and the core block 4x (4y) is displaced to the first position Pa to form the primary mold part 2x, and the core block 4y (4x) is displaced to the second position Pb. Secondary mold part 2 Characterized in that it comprises a mold clamping apparatus Mc constituting the.
[0011]
In this case, according to a preferred embodiment (form), the movable molds 2xm and 2ym are provided with movable body parts 12x and 12y that can be moved forward and backward with respect to the movable mold bases 11x and 11y. The portions 12x and 12y are separated from the movable bases 11x and 11y, and in this state, the core block 4y can be displaced to the first position Pa and the core block 4x can be displaced to the second position Pb.
[0012]
【Example】
Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.
[0013]
First, the configuration of the injection molding machine 1 according to the present embodiment will be described with reference to FIGS.
[0014]
As shown in FIG. 1, the injection molding machine 1 includes a mold clamping device Mc and a pair of injection devices Mix and Miy indicated by phantom lines. In the mold clamping device Mc, reference numeral 21 denotes a fixed plate. One end of each of the clamp shafts 22 is fixed at right angles to the four corners of the fixed plate 21, and the other end of each of the clamp shafts 22 is fixed to a drive plate (not shown). I do. A movable block 23 is slidably mounted on each of the clamp shafts 22. On the inner surface of the movable block 23 (the surface facing the fixed platen 21), a turntable 24 is arranged in an overlapping manner, and the turntable 24 is supported by a rotation drive unit 25 provided in the center of the inside of the movable block 23. As a result, the turntable 24 can be rotated in the direction of the arrow Fr shown in FIG. The rear end of the movable block 23 is connected to a mold clamping cylinder (not shown). As a result, the movable block 23 can be moved forward and backward along the clamp shafts 22 to perform mold clamping or mold opening.
[0015]
On the other hand, a pair of movable dies 2xm and 2ym is mounted on the rotary plate 24 at a position 180 ° opposite to the center, and a pair of movable dies 2xm and 2ym are fixed on the fixed platen 21 facing each movable die 2xm and 2ym. The fixed dies 2xc and 2yc are mounted. As a result, a pair of mold portions 2x and 2y is formed, and the fixed mold 2xc side becomes the primary mold portion 2x, and the fixed mold 2yc side becomes the secondary mold portion 2y. Since the movable molds 2xm and 2ym are used interchangeably, the reference numerals 2xm and 2ym do not indicate individual movable molds, but the movable mold facing the fixed mold 2xc is 2xm, and the fixed mold 2yc is used. The opposing movable mold is 2 ym.
[0016]
In addition, a primary molding cavity Ccx is formed on the parting surface of the fixed mold 2xc, and a secondary molding cavity Ccy is formed on the parting surface of the fixed mold 2yc. On the other hand, the movable mold 2xm includes a movable base 11x fixed to the turntable 24 and a movable main body 12x capable of moving forward and backward with respect to the movable base 11x, and the movable mold 2ym is fixed to the turntable 24. A movable base 11y, and a movable main body 12y capable of moving forward and backward with respect to the movable base 11y. The movable mold body 12x has a parting surface Sx, and a primary molding cavity Cx is formed on the parting surface Sx, and the movable mold body 12y has a parting surface Sy. To form the primary molding cavity Cy. The movable body portions 12x are slidably supported by guide bars 26x (see FIGS. 2 and 5) arranged in parallel with the clamp shafts 22.
[0017]
Further, guide recesses 27x, 27y are provided in the movable mold bases 11x, 11y, respectively, and guide holes 28x, 28y corresponding to the positions of the guide recesses 27x, 27y are provided in the movable mold main bodies 12x, 12y. Are provided. The guide recess 27x and the guide hole 28x accommodate the core block 4x extending between the guide recess 27x and the guide hole 28x, and the guide recess 27y and the guide recess 27y And the core block 4y straddling the guide hole 28y. The core block 4x has a core parting surface Sxb which is a part of the parting surface Sx. The primary molding cavity Cxx and the secondary molding cavity Cxy are formed side by side on the core parting surface Sxb. The block 4y has a core parting surface Syb which is a part of the parting surface Sy, and forms a primary molding cavity Cyx and a secondary molding cavity Cyy on the core parting surface Syb.
[0018]
Thus, each of the core blocks 4x and 4y can be displaced along the guide recesses 27x and 27y and the guide holes 28x and 28y. That is, the core blocks 4x and 4y can be displaced in the plane direction Fs of the parting surfaces Sx and Sy, and are selectively moved to the first position Pa for performing the first molding or the second position Pb for performing the second molding. be able to. 29x (FIG. 6) indicate drive cylinders for moving the respective core blocks 4x. The guide recess 27x and the guide hole 28x constitute a recess 3x provided in the movable mold 2xm, and the guide recess 27y and the guide hole 28y constitute a recess 3y provided in the movable mold 2ym. Accordingly, the primary mold portion 2x can be configured by displacing the core block 4x (4y) to the first position Pa, and the secondary mold portion 2y can be configured by displacing the core block 4y (4x) to the second position Pb. it can.
[0019]
Next, the operation of the injection molding machine 1 including the injection molding method according to the present embodiment will be described according to the flowchart shown in FIG. 3 with reference to FIGS.
[0020]
First, a mold clamping cylinder (not shown) of the mold clamping device Mc is drive-controlled, and the movable block 23 is advanced to the fixed platen 21 side to perform mold clamping (step S1). At the time of mold clamping, the core block 4x of the primary mold part 2x is displaced to the first position Pa, and the core block 4y of the secondary mold part 2y is displaced to the second position Pb. Accordingly, in the primary mold portion 2x, as shown in FIG. 4, the primary molding cavity Cx of the movable mold 2xx and the primary molding cavity Cxx of the core block 4x are combined with the primary molding cavity Ccx of the fixed mold 2xc. At the same time, in the secondary mold part 2y, as shown in FIG. 7, the secondary molding cavity Cy of the movable mold 2ym and the secondary molding cavity of the core block 4y are formed with respect to the secondary molding cavity Ccy of the fixed mold 2yc. For use are combined. Further, the first molded body Af primarily formed by the primary mold portion 2x is set as it is on the secondary mold portion 2y.
[0021]
Upon completion of the mold clamping, each of the injection devices Mix and Miy is nozzle-touched. Then, the primary molding resin is injected and filled into the primary mold part 2x to perform primary molding (step S2). This state is shown in FIG. At the same time, the secondary molding resin is injected into the secondary mold part 2y to perform secondary molding (step S3). FIG. 7 shows this state. Thereby, the primary molded body Af is molded in the primary mold part 2x, and the secondary molded body (composite molded article) A is molded in the secondary mold part 2y. On the other hand, the mold is opened after the pressure holding step and the cooling step are completed (step S4). In this case, the drive of the mold clamping cylinder of the mold clamping device Mc is controlled, and the movable block 23 is moved backward.
[0022]
When the mold is opened, the movable mold base 11x retreats to a preset position with respect to the fixed mold 2xc. At this time, the movable body 12x retreats together with the movable base 11x along the guide bars 26x, but the retracted position is regulated by the stopper bars 30x (see FIGS. 2 and 5). Therefore, at the fully open position, as shown in FIG. 5, the movable main body 12x is separated from the movable base 11x (and the core block 4x) by a predetermined distance G (step S5). This state is shown in FIG. Although FIG. 5 shows only the primary mold part 2x, the positional relationship between the fixed mold 2yc, the movable base 11y (and the core block 4y), and the movable mold body 12y in the secondary mold part 2y is also the same as in FIG. , The movable main body 12y is separated from the movable base 11y by the same interval as the above-mentioned predetermined interval G (step S6).
[0023]
On the other hand, by opening the mold, the first molded body Af of the primary mold part 2x is held by the movable mold main body part 12x, released from the core block 4x, and the composite molded product A in the secondary mold part 2y is The protrusion is ejected by an ejector pin (not shown), and is taken out of the mold 2y. As a result, the core blocks 4x and 4y can be displaced, so that the drive cylinder 29x is drive-controlled to move the core block 4x of the primary mold part 2x from the first position Pa shown in FIG. It is moved to two positions Pb (step S7). Similarly, the core block 4y of the secondary mold part 2y is moved from the second position Pb to the first position Pa (Step S8).
[0024]
Thereafter, the drive of the rotation drive unit 25 is controlled, and the turntable 24 is rotated by 180 ° in the direction of the arrow Fr shown in FIG. 2 (step S9). As a result, the movable mold 2xm holding the first molded body Af becomes the movable mold 2ym, and forms the secondary mold part 2y by being combined with the fixed mold 2yc. The primary mold part 2x is formed by combining the fixed mold 2xc with the fixed mold 2xc. If there is the next molding, the mold is clamped, and the same process is repeated (steps S10, S1,...).
[0025]
As described above, according to the injection molding method (injection molding machine 1) according to the present embodiment, a composite molded product (secondary molding) as shown in FIGS. 8 and 9 wrapping a part Afp of the primary molded body Af therein. Even when the body A is molded, the first molded body Af is molded as it is held in the movable mold 2xm. Therefore, unlike the related art, the step of once removing the first molded body Af and transferring it to the secondary mold is not required, so that the molding cycle can be shortened and the production efficiency can be drastically increased. Eliminating the need for an unloader and the like makes it possible to significantly reduce the cost and size (saving space) of the molding equipment.
[0026]
Although the embodiment has been described in detail above, the present invention is not limited to such an embodiment, and the configuration, shape, quantity, method, and the like of the details can be arbitrarily set without departing from the gist of the present invention. Can be changed, added, or deleted.
[0027]
For example, although the round bar-shaped molded product has been exemplified as the composite molded product A, the present invention can be applied to any composite molded product including a square rod-shaped molded product and a part of the primary molded body inside. Also, the case where the primary molding cavities Cxx and the secondary molding cavities Cxy are provided in the core block 2x is shown. However, one or more n-th molding cavities are further provided, and the composite molded product A is exemplified. It is also possible to provide a multi-colored secondary forming portion which changes in the axial direction in the secondary forming portion As. In this case, the number of n-th molds required for the increasing number of n-th molding cavities is required, but basically, the present invention can be similarly performed by regarding the n-th mold as a secondary mold. Can be applied to
[0028]
【The invention's effect】
As described above, the injection molding machine according to the present invention provides a concave portion on the parting surface of each movable mold, and the concave portion has a first position and a second position in the surface direction where the primary molding cavity and the secondary molding cavity are provided. Each of the core blocks that can be selectively displaced to the two positions is accommodated, and the core block is displaced to the first position to constitute a primary mold part, and the core block is displaced to the second position to be a secondary mold. It has a mold clamping device that constitutes the part, and also selects the first position and the second position in the surface direction where the primary molding cavity and the secondary molding cavity are provided in the concave part provided on the parting surface of each movable mold. Each of the core blocks in the primary mold part is displaced to the first position to perform primary molding, and the core block in the secondary mold part is displaced to the second position. Next molding Because there was Unishi, a marked effect as follows.
[0029]
(1) Since it is not necessary to take out the first molded body once and transfer it to the secondary mold as in the conventional case, it is possible to shorten the molding cycle when molding a composite molded product, thereby improving production efficiency (productivity). ) Can be dramatically increased.
[0030]
(2) Since a molded article unloading machine or the like is not required, the cost of the molding equipment can be significantly reduced and the size can be reduced (the space can be saved).
[0031]
(3) According to a preferred embodiment, the primary molding cavity and the secondary molding cavity are provided in the core block, the primary molding cavity is provided in the movable die, and the movable die can be advanced and retracted with respect to the movable die base. When the mold is opened, the movable body is separated from the movable base, and the core block is displaced to the first position or the second position in this state. First, a smooth molding operation can be ensured.
[Brief description of the drawings]
FIG. 1 is a vertical sectional side view of an injection molding machine (mold clamping device) according to a preferred embodiment of the present invention;
FIG. 2 is a front view showing a parting surface of a movable mold in the injection molding machine;
FIG. 3 is a flowchart (process diagram) for explaining the operation of the injection molding machine including the injection molding method according to the preferred embodiment of the present invention;
FIG. 4 is a longitudinal sectional side view of a primary mold at the time of mold clamping when molding by the injection molding method.
FIG. 5 is a longitudinal sectional side view of a primary mold when the mold is opened when molding by the injection molding method.
FIG. 6 is a longitudinal sectional side view of a primary mold showing a state in which a core block can be moved when the mold is opened at the time of molding by the injection molding method;
FIG. 7 is a longitudinal sectional side view of a secondary mold at the time of mold clamping when molding by the same injection molding method,
FIG. 8 is an external perspective view of a composite molded article (secondary molded body) molded by the injection molding method.
FIG. 9 is a cross-sectional view of the center of the composite molded article (secondary molded body).
[Explanation of symbols]
1 Injection molding machine 2x Primary mold part 2y Secondary mold part 2xm Movable mold 2ym Movable mold 3x Concave part 3y Concave part 4x Core block 4y Core block 11x Movable mold base 11y Movable mold base 12x Movable mold body 12y Movable mold body A Secondary molded body Af Primary molded body Afp Part of primary molded body Sx Parting surface Sy Parting surface Fs Surface direction Pa First position Pb Second position Mc Mold clamping device Cxx Primary molding cavity Cyx Primary molding cavity Cxy 2 Primary molding cavity Cyy Secondary molding cavity Cx Primary molding cavity Cy Primary molding cavity

Claims (4)

It has a primary mold part for molding the primary molded body and a secondary mold part for molding the secondary molded body, and after the primary molded body is primarily molded by the primary mold part, it is located at the primary mold part. The movable mold having the primary molded body is exchanged with the movable mold located at the secondary mold part, and the secondary molded part is formed by the secondary mold part into a secondary molded body enclosing a part of the primary molded body. In the injection molding method, a core block that can be selectively displaced to a first position and a second position in a surface direction in which a primary molding cavity and a secondary molding cavity are provided in a concave portion provided on a parting surface of each movable mold. And the primary molding is performed by displacing the core block in the primary mold part to the first position, and displacing the core block in the secondary mold part to the second position by the secondary molding. Injection molding method characterized by performing molding The movable mold includes a movable main body that can be moved forward and backward with respect to the movable base, and when the mold is opened, the movable main body is separated from the movable base. In this state, the core block is moved to the first position. 2. The injection molding method according to claim 1, wherein the displacement is performed to a position or the second position. It has a primary mold part for molding a primary molded body and a secondary mold part for molding a secondary molded body, and a movable mold located in the primary mold part and a movable mold located in the secondary mold part. In an injection molding machine having a mold clamping device configured to be exchangeable, a concave portion is provided on a parting surface of each movable mold, and a first position in a surface direction where a primary molding cavity and a secondary molding cavity are provided in the concave portion. And a core block that can be selectively displaced to the second position, and the core block is displaced to the first position to constitute the primary mold portion, and the core block is displaced to the second position. An injection molding machine comprising a mold clamping device configured to form the secondary mold part. The injection molding machine according to claim 3, wherein the movable mold includes a movable mold main body that can be moved forward and backward with respect to the movable mold base.

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