JPS6321391Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a layered resin injection molding machine for molded products in which many types of resin with different colors etc. are molded in layers. This invention relates to a layered resin injection molding machine in which an injection unit is equipped with upper molds each having a different mold engraving space.

Conventionally, in a layered resin injection molding machine that molds a molded product in which many types of resin with different colors are molded in layers, a plurality of resin passages (sprue bushes) are connected to the upper part of the mold. An upper die-sinking space is formed, and a lower die, which has a lower die-sinking space that matches one of the upper die-sinking spaces, is rotatably arranged relative to the upper die, and is used for each work process. By rotating the lower mold and aligning the lower mold-engraving space with a different upper mold-engraving space, the shape of the mold-engraving space is changed, and injection units filled with different types of resin are injected at each work station. , it was common for molding operations to be carried out by successively contacting different sprue bushes.

However, in the above-mentioned conventional technology, the mold is provided with a plurality of sprue bushes and a rotatable lower mold, so the structure of the mold becomes complicated, and a special design and a special method are required for this purpose. The drawback was that it required extensive processing, and the cost of the mold was inevitably high.

Moreover, since it includes movable parts, it has the disadvantage that it is prone to failure during operation, which tends to lead to a decrease in work efficiency.

The purpose of this invention was to solve problems such as the complexity of the mold structure in layered resin injection molding machines based on the conventional technology described above, and to solve problems such as the complexity of the mold structure in the layered resin injection molding machine based on the above-mentioned conventional technology. The present invention aims to provide an excellent layered resin injection molding machine that eliminates the above-mentioned drawbacks, overcomes the difficulties, and simplifies the structure of the mold.

The structure of this invention in accordance with the above purpose is that the upper mold, in which different mold engraving spaces are formed at each work station, is brought into contact with the lower mold that is sequentially transferred to each work station. The first work station molds the first molding layer by injecting resin into the molding space from injection units that are integrally formed with each of the molds and filled with resins of different materials. At the second work station, a second molding layer is laminated and molded on the first molding layer,
The gist of this invention is to enable multilayer molding to be easily achieved in the same manner.

Next, an embodiment of this invention will be described below based on the drawings.

In FIG. 1, a plurality of
In the illustrated example, four lower molds 2 are installed and fixed. A plurality of molding work stations 3 ₁ , 3 ₂ ,
3 ₃ and a take-out work station 4 are provided, and the molding work stations 3 ₁ , 3 ₂ , 3 ₃ are provided with
Injection units 5 ₁ , 5 ₂ , 5 supported so that they can be raised and lowered
₃ is equipped.

As shown in FIG. 2, the injection unit 5 ₁ ,
Heating cylinders 6 ₁ , 6 ₂ , 6 ₃ at the lower ends of 5 ₂ , 5 ₃ (heating cylinder 6 ₃ is omitted in the figure) have upper molds 7 ₁ , 7 ₂ ,
7 ₃ (similarly, the lower mold 7 ₃ is not shown) are each removably attached by appropriate fixing means. Each injection unit 5 is raised and lowered by a mold clamping cylinder 8 connected to the upper end.
The upper mold 7 and lower mold 2 are opened and closed.

Here, an explanation will be given taking as an example a case in which a molded article 10 consisting of three molding layers 11, 12, and 13 as shown in FIG. 3 is molded.

As shown in FIG. 4, the same die engraving space 14 is formed in the lower die 2 through each of the work stations 3 ₁ , 3 ₂ , 3 ₃ . On the other hand, regarding the upper mold 7, the upper mold 7 ₁ at the first work station 3 ₁
In this case, a mold engraving space 15 ₁ corresponding to the first molding layer 11 of the molded product 10 is formed, and the upper die 7 ₂ in the second work station 3 ₂ is used to form a molding space 15 1 corresponding to the first molding layer 11 of the molded product 10 . Die engraving space 15 corresponding to
₂ is formed, and in the upper mold 7 ₃ at the third work station 3 ₃ , the third molding layer 1 of the molded product 10 is formed.
A mold engraving space 15 ₃ corresponding to shapes up to 3 is formed.

In the above configuration, in each work station 3, the injection unit 5 is lowered by the mold clamping cylinder 8, and the upper mold 7 and the lower mold 2 are closed and further brought into a mold clamping state. As shown in Figure 4, the first
At the work station 3 ₁ , the first molding layer 11 of the molded product 10 is formed by the engraving spaces 14 and 15 ₁ of the lower die 2 and the upper die 7 ₁ (FIG. 4A). Next, at the second work station ₃₂ , the die-carving spaces 14,1
5 ₂ , the second molding layer 12 is laminated and molded on the first molding layer 11 (FIG. 4B).

Finally, at the third work station 3 ₃ , _the second molding layer 12 is
A third molding layer 13 is laminated thereon (FIG. 4C) to complete the molded product 10.

Incidentally, the molding operations at each of the work stations 3 are performed simultaneously and synchronously.

Molded product 1 molded at molding work station 3
0 is removed from the lower mold 2 at the next removal work station 4. Inserts are also inserted here if necessary.

In the above embodiment, the number of molding work stations 3 is described as three, but the number is not limited to this, and it goes without saying that the number may be set in accordance with the laminated structure of the molded product 10.

As mentioned above, according to this invention, the lower mold is installed on a rotary table and sequentially transferred to the molding work stations, while the upper mold is directly attached to the injection unit provided at each work station. By forming different mold engraving spaces, when each molding layer of a molded product is laminated and molded sequentially and stepwise at each work station, the lower mold has a common space at each work station. The structure of the mold is simple, as the same die-cutting space is formed, and different die-cutting spaces are formed in the upper die depending on the laminated structure of the molded product at each work station. Since there are no movable parts such as a lower die rotation mechanism, there are fewer failures.
This has the excellent effect of significantly improving operational reliability.

Moreover, since the upper die has its own engraving space corresponding to the work station, it is extremely suitable for use in a molding machine in which the upper die is directly attached to the injection unit. By doing this, the upper mold plate that was conventionally required can be omitted, which simplifies the overall structure, and also reduces costs, along with the simplification of the mold structure.
It has the advantage of being significantly economical.

Moreover, since the molding work is carried out simultaneously and synchronously through each work station, there is no waste in the overall work at each work station.
It also has the effect of allowing you to work more efficiently.

[Brief explanation of the drawing]

The figure shows an example of this invention.
The figure is a top view, FIG. 2 is a partially omitted side view, FIG. 3 is a sectional view of the molded product, and FIG. 4 is an explanatory diagram of the operation. 1... Rotating table, 2... Lower mold, 3... Molding work station, 5... Injection unit, 6...
Heating cylinder, 7... Upper mold, 10... Molded product, 11, 1
2, 13...first, second, and third molding layers, 14...lower die engraving space, 15...upper die engraving space.

Claims (1)

[Scope of utility model registration request] A plurality of lower molds 2 are installed on a rotary table 1 and have the same mold engraving space 14 formed therein, and a plurality of injection units 5 are provided at work stations 3 at a plurality of locations along the circumference of the rotary table. A layered resin injection molding machine comprising an upper mold 7 attached to each of the plurality of injection units and having a different mold engraving space 15 formed therein.