JP3047212B2 - Molding method and molding die for laminated molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a fixed type, a movable type,
Using a pair of rotary molds rotatably provided in these molds, a mold composed of a holding device, and the like, a method of forming a laminate formed article, which is used to mold a laminated formed article, and a method of forming the laminate. It relates to a molding die used for implementation.

[0002]

2. Description of the Related Art According to an injection molding method, various molded products can be obtained. However, recently, in order to further increase the added value, a laminated molded product, for example, around a hard material for imparting strength. In addition, a laminated molded product in which a soft material for giving a soft touch feeling is integrally molded is molded. As a method of forming such a laminated formed article, a method of preparing two molds, sequentially molding while replacing these molds, embedding a primary molding insert in the mold, and forming a space around the mold. There is known an insert molding method and the like obtained by injecting a soft material into the material.

[0003]

The conventional molding method as described above can provide a laminated molded product. However, according to the former method, two molds must be prepared. There are drawbacks that the manufacturing cost of the mold increases and the cost of machinery and equipment for operating the mold increases. In addition, the insert method has the disadvantage that the cost of mechanical equipment is similarly high and the molding method is complicated. Accordingly, an object of the present invention is to provide a method of forming a laminated formed article, which can obtain a laminated molded article at low cost, and a mold used for carrying out this method.

[0004]

According to the present invention, there is provided a mold for molding a plurality of articles according to the present invention.
Using a movable mold, a pair of rotating molds rotatably provided in these molds, and a mold composed of a holding device,
In the primary molding, a first molten resin is injected and filled into a cavity formed by the fixed die, the movable die, the rotary die, and the holding device to form a primary molded product. The movable mold was opened while a part of the next molded product was held by the holding device, and the rotary mold was rotated to secure a cavity for secondary molding outside the primary molded product. The cavity is configured to be injection-filled with a second molten resin. According to a second aspect of the present invention, the holding member of the holding device according to the first aspect is configured to form a part of a primary molded product. The invention according to claim 3 is a mold comprising a fixed mold, a movable mold, a pair of rotating molds rotatably provided in these molds, and a holding device, wherein the pair of rotations The mold has a first concave portion in which a first cavity having a relatively small shape is formed at the first position, and a second cavity having a relatively large shape in a second position rotated by a predetermined angle from the first position. At least two second recesses are provided, respectively, and the holding device is composed of a pair of holding members movably provided on the fixed die and the movable die, respectively. It is urged to move toward the line side. According to a fourth aspect of the present invention, a concave portion is formed at a tip portion of the pair of holding members according to the third aspect, and these concave portions constitute a cavity having substantially the same size as the second cavity. ing.

Accordingly, the pair of rotary dies are rotated to the first position where the relatively small first cavity is formed. Then, the movable mold is clamped to the fixed mold. Then, a cavity for primary molding is formed by the movable mold, the fixed mold, the pair of rotary molds, and the holding device. Therefore,
For example, a weighed first injection material is injected and filled into a cavity from a two-head injection molding machine to perform primary molding. When the primary molded product has solidified, slightly open the movable mold. Then, the primary molded product is held by the holding device in a state of being separated from the fixed mold, the movable mold, the pair of rotary molds, and the like. The pair of rotary molds is rotated while being held, and is brought to the second position where a cavity for secondary molding is secured outside the primary molded product. Then, the movable mold is clamped to the fixed mold. Then the second
The injection material is injected and filled into the cavity to perform secondary molding.
After cooling and solidification, open the movable mold and take out the molded product.
Hereinafter, the same operation is repeated to mold.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described with reference to a mold for molding a handle and a molding method therefor. The handle T is configured as a door handle or a handle for lowering luggage. As shown in FIG. 3, the handle T includes a central grip portion N and ends S, S on both sides of the grip portion N. Assume that it is configured. The entire ends S, S and the core N ′ of the grip N are made of a hard material such as an acrylic resin A.
And the periphery of the grip N is assumed to be molded from the soft material elastomer E.

FIG. 1 shows a mold according to an embodiment of the present invention.
As shown in FIG. 1, a fixed mold 1, a movable mold 10 forming a pair with the fixed mold 1, a first rotary mold 20 rotatably provided inside the fixed mold 1, and an inside of the movable mold 10. Similarly, a second rotary mold 20 ′ rotatably provided, and two holding devices 30, which are provided vertically above and below the rotary molds 20 and 20 ′ in FIG. 30 'and the like.

On the parting line P side of the fixed mold 1,
First and second concave portions 2, 3 for forming approximately half of the end portions S, S of the handle T described with reference to FIG. 3 are formed vertically. Also, on the parting line P ′ side of the movable die 10, first and second concave portions 12 and 13 that form a pair with the first and second concave portions 2 and 3 of the fixed die 1 are similarly provided.
Therefore, when the movable mold 10 is clamped to the fixed mold 1 as shown in FIG.
The two recesses 2, 3 and 12, 13 define an upper cavity 4 and a lower cavity 5 for molding the ends S, S and tips S ', S' of the handle T.
The fixed die 1 is provided with a first sprue 27 communicating with the first recess 2.

Thus, the fixed mold 1 and the movable mold 10 include:
Upper and lower cavities 4 and 5 each having a shape divided by the first and second concave portions 2, 3 and 12 and 13 are formed, and the first and second cavities 4 and 5 are filled so as to fill the cavities 4 and 5.
Rotary molds 20, 20 'are rotatably provided.
In order to rotatably support the first and second rotary molds 20 and 20 ′ around an axis perpendicular to the plane of FIG. 1B, the fixed mold 1 and the movable mold 10 include a rotary mold. Bearing holes 6, 16
Are provided respectively. These rotary mold support holes 6 and 16 are partially open at the parting lines P and P ′. Therefore, the first and second rotary molds 2 to be described later
The first and second parting surfaces 21, 21 'and 24, 24' of 0, 20 'can be flush with the parting lines P, P' of the fixed die 1 and the movable die 10. Openings 7 and 17 are also opened on the opposite sides of these openings, and the first and second rotary molds 2 are opened from these openings 7 and 17.
0 and 20 'are also rotated.

Since the first and second rotary molds 20 and 20 'have substantially the same structure, the first rotary mold 2 and 20' will be mainly described hereinafter.
0, and for the second rotary mold 20 ′,
In the figures, the same reference numeral is added with a dash "'" and will not be described repeatedly. When the movable mold 10 is clamped to the fixed mold 1, the first rotary mold 20 is flush with the parting line P as shown in FIG. The first parting surface 21 is formed by cutting off part of a chord. The first parting surface 21 is provided with a first rotary concave portion 22 having a relatively small diameter. The first rotary recess 22 and the second rotary mold 2
With the first rotating recess 22 'of 0', the first rotating recess 22 'for forming the core N' of the grip portion N of the handle T shown in FIG.
Is formed. In addition, a second parting surface 24 is similarly formed at right angles to the first parting surface 21, and the second parting surface 24 also has a second rotating part having a diameter larger than that of the first rotating concave part 22. A recess 25 is formed. The second rotary recess 25 and the second rotary mold 2
The grip portion N of the handle T is formed by the second rotation concave portion 25 'of 0'.
Is formed.
The second cavity 26 is shown in FIGS.

The first rotary mold 20 includes (a) in FIG.
As shown in (b), the second sprue 28 is provided so as to penetrate the first rotary mold 20. One of the second sprues 28 is opened in the second rotating concave portion 25, and when the second rotating concave portion 25 is rotated to the second position facing the parting line P, the other of the fixed die 1 is rotated. It is located on the opening 7 side.

Since the holding devices 30, 30 'provided above and below the rotary molds 20, 20' have the same structure, the upper holding device 30 will be mainly described below.
The lower holding device 30 ′ has the same reference numerals in the figure with a dash “′” and will not be redundantly described. Holding device 30
Is composed of a pair of holding members 31, 31 and spring members 32, 32, as best shown in FIG. These holding members 31, 31 are provided inside the fixed mold 1 and the movable mold 10 so as to be movable in the horizontal direction in the figure, and are urged toward the parting lines P, P 'by the spring members 32, 32, respectively. ing. Holding member 3
The reference numerals 1 and 31 each have a flange portion at the distal end, and the distal end surfaces thereof are parting surfaces 33 and 33. Recesses 34, 34 are formed in these parting surfaces 33, 33. These recesses 34, 34 constitute a cavity 35 for molding the end S of the handle T.

Next, a description will be given of a molding method using the dies 1, 10, 20, 20 'and the holding devices 30, 30'. The first and second rotary molds 20, 20 'are rotated to the first position, and the movable mold 10 is clamped to the fixed mold 1 as shown in FIG. Then, the movable mold 10 and the fixed mold 1 form upper and lower cavities 4 and 5. Further, the cavities 35, 35 'are constituted by the holding members 31, 31, and 31', 31 'of the holding devices 30, 30', and similarly, the first and second rotary molds 20, 20 'are used to form the first cavities.
Is formed. The cavities 4, 5, 35, 35 ', 23 thus configured are shown in FIG.

For example, from a two-head injection molding machine, the weighed hard material is transferred from the first sprue 27 to the cavities 4, 5, 35,
35 ′ and 23 are injection-filled to perform primary molding. The partially filled state is shown in FIG. By this primary molding, the ends S, S and the core N ′ of the handle T shown in FIG.
Is molded. When the primary molded product is solidified to some extent, the movable mold 10 is slightly opened. Then, the holding devices 30, 30 '
Holding members 31, 31 and 31'31 'are opened. Therefore, the holding members 31, 31 and 31'3
1 'protrudes outside the parting lines P, P' by the spring members 32, 32, 32, 32 'while holding the ends S, S of the primary molded product. This protruding state is shown in FIG.
Is shown in When the primary molded product is difficult to separate from the upper and lower cavities 4, 5 and the like, it can be extruded with an ejector pin or the like.

With the movable mold 10 slightly opened, the first and second rotary molds 20, 20 'are rotated to the second position while the primary molded product is held at the ends S, S. The state rotated to the second position is shown in FIG. In this second position, a second cavity 26 having a large diameter is formed by the second rotating concave portions 25 and 25 '. The movable mold 20 is clamped to the fixed mold 1. Then, the second cavity 26
Thereby, the core portion N ′ of the handle T is surrounded at a predetermined interval. The weighed soft material is injected and filled into the cavity 26 from the second sprue 28 from the two-head injection molding machine to perform secondary molding. Thereby, the soft material E is integrally formed around the outer periphery of the core N ′. FIG. 7 shows a state during the secondary molding. Waiting for cooling and solidification, movable mold 2
Open 0 and take out the molded product. Hereinafter, the same operation is repeated to mold.

The present invention is not limited to the above embodiment,
Various forms are possible. For example, in the above embodiment, the hard material is injected for the primary molding and the soft material is injected for the secondary molding. However, the injection may be performed in the reverse order to obtain a molded product having a hard material on the outside. It is also possible to inject the same material or to inject materials having different colors, physical or chemical properties of the injected material. At this time, it is obvious that a two-color injection machine or the like can be applied to the injection machine in addition to the two-head injection molding machine. In the above example, the handle T
However, a molded product other than the handle T can be molded in the same manner, and the cross-sectional shape is not limited to a circle, and for example, an unspecified molded product such as an ellipse and a polygon can be molded. It is clear that you can. Furthermore, it is also possible to form a molded product that does not require the ends S, S formed by the holding devices 30, 30 '. In this case, the holding device 3
The portions held at 0 and 30 'are also subjected to primary molding, and the portions held after secondary molding are cut off. In the embodiment shown in the figures, the holding members 31, 31, 31 ',
31 'is biased by the springs 32, 32, 32', 32 ', but it is clear that the spring can be biased by a fluid pressure such as compressed air instead of the spring.

In the above embodiment, the first and second rotary molds 2
The first and second rotating recesses 22, 22 ', 0' and 20 '
Although only 5, 25 'are provided, three or more concave portions having different diameters may be provided, and a multilayer molded product may be obtained in the same manner. Also, the first and second parting surfaces 21, 24 and 21 ', 2' of the first and second rotary molds 20, 20 ',
The 4's are at right angles to each other, but it is clear that they need not be at right angles. Further, the holding device 3
Although two 0 and 30 'are provided with the first and second rotary molds 20 and 20' interposed therebetween for stabilization, it is apparent that only one may be provided depending on the shape of the molded product. . Also, in the embodiment shown in the figure, the first sprue 2
Although 7 is provided in the fixed mold 1, it can be provided in the first rotary mold 20 by forming a hot runner so as not to short-circuit with the second sprue 28.

[0018]

As described above, according to the present invention, a mold including a fixed mold, a movable mold, a pair of rotary molds rotatably provided in these molds, and a holding device is provided. In the primary molding, a first molten resin is injected and filled into a cavity formed by a fixed die, a movable die, a rotary die, and a holding device to form a primary molded product, and the secondary molding is performed. The movable mold is opened while a part of the primary molded product is held by the holding device, and the rotary mold is rotated to secure a cavity for secondary molding outside the primary molded product, Since the secured cavity is filled with the second molten resin by injection, it is possible to mold a laminated formed article with a single-sided mold. Therefore, according to the present invention, it is possible to reduce the cost of the mold and the equipment, and to obtain the effect of being able to mold the laminated molded article at low cost. According to the second aspect of the present invention, in addition to the above effects, a part of the primary molded product is molded by the holding member of the holding device, so that the primary molded product held by the holding member can be effectively used without being cut off, for example. The effect which can be used for is obtained.

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a molding die of the present invention,
(A) is a longitudinal sectional view schematically showing a mold, and (b)
FIG. 2 is a horizontal sectional view showing a part of the broken part.

FIG. 2 is a horizontal sectional view showing a part of a molding die according to an embodiment of the present invention in a cutaway manner.

FIG. 3 is a cross-sectional view of a handle formed according to the embodiment of the present invention.

FIG. 4 is a longitudinal sectional view schematically showing a state in which primary molding is performed according to an embodiment of the present invention, with a part thereof broken away.

FIG. 5 is a horizontal sectional view schematically showing a partially opened state of the movable mold after primary molding according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating a first molding method according to an embodiment of the present invention.
FIG. 6 is a horizontal cross-sectional view schematically showing a state in which a rotary mold of No. 2 is rotated to a second position in a partial cross-section.

FIG. 7 is a longitudinal sectional view schematically showing a state in which secondary molding is being performed according to an embodiment of the present invention, with a part thereof broken away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed mold 10 Movable mold 20, 20 'Rotary mold 4, 5, 2335, 35' Primary molding cavity 26 Secondary molding cavity 30, 30 'Holding device 31, 31' Holding member

────────────────────────────────────────────────── (5) References JP-A-62-25025 (JP, A) JP-A-63-35323 (JP, A) JP-A-1-110918 (JP, A) JP-A-1- 114405 (JP, A) JP-A-3-203617 (JP, A) JP-A-4-216024 (JP, A) JP-A 8-108449 (JP, A) JP-A-63-100211 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 45/00-45/84

Claims (4)

(57) [Claims] 1. A fixed mold (1), a movable mold (10), a pair of rotating molds (20, 20 ′) rotatably provided in these molds, and a holding device (30, 20). 30 ′), in the primary molding, the fixed mold (1) and the movable mold (10).
And the rotating mold (20, 20 ') and the holding device (30, 3).
0 ′) and the cavity (4, 5, 2,
3, 35, 35 ') by injection filling with the first molten resin
In the secondary molding, the movable mold (10) is opened while a part of the primary molded article is held by the holding device (30, 30 ′), and the rotary mold (20, 20 ')
A method of molding a laminated molded article, comprising securing a cavity (26) for secondary molding outside the next molded article and injecting and filling a second molten resin into the secured cavity (26). 2. The holding device (30, 3) according to claim 1,
0 ') holding member (31, 31, 31', 31 '),
A method of forming a laminated formed product in which a part of a primary molded product is formed. 3. A fixed mold (1), a movable mold (10), a pair of rotating molds (20, 20 ′) rotatably provided in these molds, and a holding device (30, 20). 30 ′), wherein the pair of rotary molds (20, 20 ′) have a first concave portion (22) in which a relatively small first cavity (23) is formed at a first position. , 22 ′) and a second cavity (26) having a relatively large shape at a second position rotated by a predetermined angle from the first position.
And at least two second concave portions (25, 25 ') each of which is provided with the fixing device (1).
And a pair of holding members (31, 31, 31 ′, 31 ′) provided movably on the movable mold (10), respectively, and these holding members (31, 31, 31 ′,
31 ′) is a molding die for forming a laminated product which is urged to move toward the parting line (P, P ′). 4. A pair of holding members according to claim 3,
31, 31 ', 31') have concave portions (34, 3
4, 34 ', 34') are formed and these recesses (3
4, 34, 34 ', 34'), the cavities (35, 35 ') having substantially the same size as the second cavity (26).
A mold for forming a laminate formed product.