JP2002264170A - Injection molding method and injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accomplish the cost reduction and miniaturization (space saving) of a molding apparatus when a composite molding is molded and to improve production efficiency by curtailing a molding cycle. SOLUTION: After a primary molding Af is molded primarily by a primary mold part 2x, the primary mold part 2x and the movable molds 2xm and 2ym of a secondary mold part 2y are replaced, and a secondary molding A including a part Afp of the primary molding Af is molded secondarily by the secondary mold part 2y, core blocks 4x and 4y which can e displaced selectively to the first position Pa and the second position Pb in the surface direction Fs are housed in recessed parts 3x and 3y formed in the parting faces Sx and Sy of the movable molds 2xm and 2ym. The core block 4x (4y) is displaced to the first position Pa and primary molding is carried out, and the core block 4y (4x) is displaced to the second position Pb and secondary molding is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an injection molding method and an injection molding machine suitable for molding a composite molded article.

[0002]

2. Description of the Related Art Conventionally, as an injection molding machine for molding a composite molded product, Japanese Patent Application Laid-Open No. 10-11 / 1999 proposed by the present applicant has already been proposed.
An injection molding machine disclosed in 3963 is known.

This injection molding machine has a primary mold for molding a primary molded body and a secondary mold for molding a secondary molded body, and exchanges a movable mold between the primary mold and the secondary mold. The apparatus is provided with a mold clamping device configured to be capable. Thereby, after the primary molded body is primarily molded by the primary mold, the movable mold 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.

By the way, in such an injection molding machine, a composite molded article 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, is used.
Although it can be molded relatively easily, it is not easy to mold a composite molded article A in which a part Afp of the primary molded body Af is wrapped as shown in FIGS. When molding the composite molded article A, the primary molded article molded with the primary mold is once taken out of the primary mold by a molded article take-out machine or the like, and then set in a separate secondary mold. Insert molding was performed using a secondary mold. 8 and 9, As indicates a secondary molded portion molded with the secondary molding resin.

[0005]

However, such a conventional injection molding machine (injection molding method) has the following problems.

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.

Second, since it is necessary to take out the primary molded product from the primary mold once and then transfer it to another secondary mold, the molding cycle becomes longer, and the production efficiency cannot be increased.

The present invention has solved the problems existing in the prior art as described above, and can greatly reduce the cost and size of the molding equipment when molding a composite molded article (space saving). It is another object of the present invention to provide an injection molding method and an injection molding machine capable of dramatically increasing production efficiency by shortening a molding cycle.

[0009]

In the injection molding method according to the present invention, a primary molded body Af is primarily molded by a primary mold part 2x, and then a primary mold part 2x and a secondary mold part 2 are formed.
When the movable molds 2xm and 2ym of y are exchanged, and the secondary mold part 2y is used to perform secondary molding of the secondary molded body A enclosing a part Afp of the primary molded body Af, the parting of the movable molds 2xm and 2ym is performed. 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 are accommodated in the concave portions 3x and 3y provided on the surfaces Sx and Sy, and the core blocks 4x (4y) are accommodated. The primary molding is performed by displacing to the first position Pa, and the secondary molding is performed by displacing the core block 4y (4x) to the second position Pb.

Further, the injection molding machine 1 according to the present invention comprises a primary mold part 2x for molding a primary molded body Af, and a secondary molded body Ax.
In the injection molding machine having a mold clamping device Mc having a secondary mold part 2y for molding the mold and exchanging the movable molds 2xm and 2ym of the primary mold part 2x and the secondary mold part 2y, Recess 3 on 2xm, 2ym parting surface Sx, Sy
x, 3y are provided, and the core blocks 4x, 4y that can be selectively displaced to the first position Pa and the second position Pb in the plane direction Fs are accommodated in the concave portions 3x, 3y, respectively.
y) is displaced to the first position Pa to form the primary mold part 2x, and the core block 4y (4x) is moved to the second position P.
b to form the secondary mold part 2y
It is characterized by having.

In this case, according to a preferred embodiment (form), the core blocks 4x and 4y include the primary molding cavities Cxx and Cyx and the secondary molding cavities Cxy and Cy.
In addition to providing y, the movable dies 2xm and 2ym can be provided with cavities Cx and Cy for primary molding. The movable molds 2xm and 2ym are provided with movable mold bases 11x and 11ym.
movable body portions 12x, 12y capable of moving back and forth with respect to y
When the mold is opened, the movable mold main bodies 12x and 12y are separated from the movable mold bases 11x and 11y, and in this state, the core block 4y is displaced to the first position Pa and the core block 4x is displaced to the second position Pb. be able to.

[0012]

Next, preferred embodiments according to the present invention will be described in detail with reference to the drawings.

First, the configuration of an injection molding machine 1 according to the present embodiment will be described with reference to FIGS.

As shown in FIG. 1, an injection molding machine 1 includes a mold clamping device Mc and a pair of injection devices Mix and Mi indicated by phantom lines.
y. In the mold clamping device Mc, reference numeral 21 denotes a fixed platen.
Are fixed at right angles, and the other ends of the clamp shafts 22 are fixed to a drive board (not shown). 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 rotating plate 24 is arranged in an overlapping manner, and the rotating plate 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 arrow Fr shown in FIG. The rear end of the movable block 23 is connected to a mold clamping cylinder (not shown). Thereby, the movable block 2
3 can be moved back and forth along the clamp shafts 22 to open or close the mold.

On the other hand, a pair of movable dies 2xm and 2y
m, and a pair of fixed dies 2xc and 2yc are mounted on the fixed platen 21 facing the movable dies 2xm and 2ym. Thereby, a pair of mold parts 2x and 2y are formed, and the fixed mold 2xc side is the primary mold part 2x and the fixed mold 2yc.
The side becomes the secondary mold part 2y. In addition, each movable type 2xm, 2
ym are used interchangeably, so that the symbols 2xm, 2
ym does not refer to an individual movable type, but a fixed type 2x
The movable die facing c is 2xm, and the movable die facing the fixed die 2yc is 2ym.

A primary molding cavity Ccx is formed on the parting surface of the fixed mold 2xc.
On the parting surface of the fixed mold 2yc, a secondary molding cavity Ccy is formed. On the other hand, the movable mold 2xm includes a movable base 11x fixed to the turntable 24, and the movable base 1x.
The movable mold 2ym includes a movable base 11y fixed to the turntable 24, and a movable body 11y movable forward and backward with respect to the movable base 11y. 12y. The movable mold body 12x has a parting surface Sx, a primary molding cavity Cx is formed on the parting surface Sx, and the movable mold body 12y has a parting surface Sy,
This parting surface Sy is provided with a primary molding cavity Cy.
To form In addition, each movable main body portion 12x is provided with guide bars 26x arranged in parallel with the clamp shafts 22.
(See FIG. 2 and FIG. 5).

Further, guide recesses 27x and 27y are respectively provided in the movable bases 11x and 11y, and guide holes corresponding to the positions of the guide recesses 27x and 27y are formed in the movable main bodies 12x and 12y. 28x, 2
8y are provided. The guide recess 27x and the guide hole 28x accommodate the core block 4x that extends between the guide recess 27x and the guide hole 28x, and the guide recess 27y and the guide recess 27y within the guide hole 28y. And the core block 4y straddling the guide hole 28y. The core block 4x has a core parting surface Sxb that 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, and the core block 4y is formed on the parting surface Sy.
Has a core parting surface Syb, which is a part of the primary molding cavity Cy.
x and the secondary molding cavity Cyy are formed side by side.

Thus, each core block 4x, 4y
Are the guide recesses 27x, 27y and the guide holes 28x, 2
8y can be displaced. That is, each core block 4
x and 4y can be displaced in the plane direction Fs of the parting surfaces Sx and Sy, and can be selectively moved to the first position Pa where the first molding is performed or the second position Pb where the second molding is performed. 29x (FIG. 6) indicate drive cylinders for moving the respective core blocks 4x. The guide recess 27x
And the guide hole 28x are provided in the 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 die 2ym. Accordingly, the primary mold portion 2x can be configured by displacing the core block 4x (4y) to the first position Pa, and the core block 4y
By displacing (4x) to the second position Pb, the secondary mold part 2y can be configured.

Next, the operation of the injection molding machine 1 including the injection molding method according to this embodiment will be described with reference to FIGS. 1 and 2 and FIGS. 4 to 7 in accordance with the flowchart shown in FIG.

First, a mold clamping cylinder (not shown) of the mold clamping device Mc is driven and controlled, and the movable block 23 is advanced to the fixed platen 21 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 moved to the second position P.
b. Therefore, in the primary mold part 2x,
As shown in FIG. 4, the primary molding cavity Cx of the movable mold 2xm and the primary molding cavity Cx of the core block 4x are provided for the primary molding cavity Ccx of the fixed mold 2xc.
xx are combined, and in the secondary mold part 2y, FIG.
As shown in the figure, the secondary molding cavity C of the fixed mold 2yc
cy, the secondary molding cavity C of the movable mold 2ym
y and cavity Cyy for secondary molding of core block 4y
Are combined. In addition, the first molded body Af which is primarily molded by the primary mold part 2x is set as it is on the secondary mold part 2y.

Upon completion of the mold clamping, each of the injection devices Mix, M
Nozzle touch iy. Then, the primary molding resin is injected into the primary mold portion 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). This state is shown in FIG. 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.

When the mold is opened, the movable base 11x is retracted to a preset position with respect to the fixed mold 2xc. At this time, the movable body 12x moves backward 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. FIG. 5 shows only the primary mold part 2x, but the fixed mold 2yc and the movable base 11y (and the core block 4y) in the secondary mold part 2y.
y), the positional relationship between the movable main body 12y is also the same as that of FIG. 5, and the movable main body 12y is separated from the movable base 11y by the same interval as the above-mentioned predetermined gap G (step S).
6).

On the other hand, by opening the mold, the first molded body Af of the primary mold portion 2x is held by the movable mold body portion 12x, released from the core block 4x, and formed into a composite molded product in the secondary mold portion 2y. A is ejected from the mold 2y by being ejected by an ejector pin (not shown). 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. 5 to the first position Pa shown in FIG. It is moved to two positions Pb (step S7). Similarly, the core block 4 of the secondary mold part 2y
y is moved from the second position Pb to the first position Pa (Step S8).

Thereafter, the rotation drive unit 25 is drive-controlled to rotate the turntable 24 by 180 ° in the direction of 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 the fixed mold 2xm.
The secondary mold part 2y is constituted by combining with the yc, and the vacant movable mold 2ym becomes the movable mold 2xm, and constitutes the primary mold part 2x by being combined with the fixed mold 2xc. If there is the next molding, the mold is clamped, and the same process is repeated (step S1).
0, S1 ...).

As described above, according to the injection molding method (the injection molding machine 1) according to the present embodiment, a part Af of the primary molded body Af
Even when molding a composite molded article (secondary molded article) A as shown in FIGS. 8 and 9 wrapping p inside, the first molded article Af is molded as it is held in the movable mold 2 × m. Is done. 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 dramatically improved, and the molded product can be formed. 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.

The embodiment has been described in detail above.
The present invention is not limited to such an embodiment,
The configuration, shape, quantity, method, etc. of the details can be arbitrarily changed, added, or deleted without departing from the gist of the present invention.

For example, although the round molded article is exemplified as the composite molded article A, the present invention can be applied to any composite molded article including a square rod-shaped molded article 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 exemplified composite molded product A is provided. Secondary molding As in
May be provided with a multicolored secondary forming portion that changes in the axial direction. In this case, the number of n-order molds corresponding to the increasing number of n-order molding cavities is required. However, basically, the present invention is applied to the same manner by considering the n-order mold as a secondary mold. Can be applied to

[0028]

As described above, according to the injection molding machine of the present invention, the core block which can be selectively displaced to the first position and the second position in the surface direction is provided in the concave portion provided on the movable parting surface. Accommodating, while configuring the primary mold portion by displacing the core block to the first position, comprising a mold clamping device to configure the secondary mold portion by displacing the core block to the second position,
By using this injection molding machine, the injection molding method according to the present invention performs primary molding by displacing the core block to the first position and performs secondary molding by displacing the core block to the second position. Therefore, the following remarkable effects are obtained.

(1) Since the step of once taking out the first molded body and transferring it to the secondary mold as in the conventional case is not required, the molding cycle for molding the composite molded article can be shortened, thereby improving the production efficiency. (Productivity) can be dramatically improved.

(2) Since a molded product take-out machine is not required, the cost of the molding equipment can be greatly reduced and the size can be reduced (the space can be saved).

(3) According to a preferred embodiment, a primary molding cavity and a secondary molding cavity are provided in the core block, a primary molding cavity is provided in the movable mold, and the movable mold is provided with respect to the movable mold base. If the movable block main body is provided with a movable main body that can be moved forward and backward, and the mold is opened, the movable main body is separated from the movable base, and in this state, the core block is displaced to the first position or the second position. The smooth molding operation can be ensured, including the movement of the material.

[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 chart) 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 and pointed at the time of opening the mold when molding by the injection molding method.

FIG. 7 is a vertical sectional side view of a secondary mold at the time of mold clamping when molding by the injection molding method.

FIG. 8 is an external perspective view of a composite molded product (secondary molded body) molded by the injection molding method.

FIG. 9 is a cross-sectional view of the center of the composite molded product (secondary molded body).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Injection molding machine 2x Primary mold part 2y Secondary mold part 2xm Movable mold 2ym Movable mold 3x Depression 3y Depression 4x Core block 4y Core block 11x Movable base 11y Movable base 12x Movable main body 12y Movable main 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 Two Primary molding cavity Cyy Secondary molding cavity Cx Primary molding cavity Cy Primary molding cavity

Claims (6)

[Claims] After the primary molded body is primarily molded by a primary mold part, the movable molds of the primary mold part and the secondary mold part are exchanged, and the primary molded body is formed by the secondary mold part. In the injection molding method for performing secondary molding of a secondary molded body enclosing a part, a core which can be selectively displaced to a first position and a second position in a surface direction in a concave portion provided on a parting surface of the movable mold. Injection molding method for accommodating a block, performing the primary molding by displacing the core block to the first position, and performing the secondary molding by displacing the core block to the second position. . 2. The movable mold includes a movable body that can be moved forward and backward with respect to a movable mold base. When the mold is opened, the movable mold body is separated from the movable mold base. The injection molding method according to claim 1, wherein the block is displaced to the first position or the second position. 3. It has a primary mold part for molding a primary molded body and a secondary mold part for molding a secondary molded body, and the movable molds of the primary mold part and the secondary mold part are exchangeable. In the injection molding machine provided with the mold clamping device configured as described above, a concave portion is provided on the parting surface of the movable die, and the concave portion accommodates a core block that can be selectively displaced to a first position and a second position in a surface direction. The core block is displaced to the first position to constitute the primary mold portion, and the mold block is displaced to the second position to constitute the secondary mold portion. An injection molding machine characterized in that: 4. The injection molding machine according to claim 3, wherein the core block has a primary molding cavity and a secondary molding cavity. 5. The injection molding machine according to claim 3, wherein the movable mold has a primary molding cavity. 6. The injection molding machine according to claim 3, wherein the movable mold has a movable mold main body that can move forward and backward with respect to the movable mold base.