JPH01314148A - Foamed styrol molding machine - Google Patents

Abstract

PURPOSE:To enhance the number of shots per hr by providing a heat exchange element for promoting the heat exchange of heating and cooling to the non- molding surface of a mold. CONSTITUTION:A moving chamber 7 is moved to the left by the cylinder rod 80 of a clamping cylinder 8 to engage protruding molds 9, 10 with recessed molds 16, 17 and a molding material is injected in the molds as usual and steam is respectively sprayed in chambers 7, 23 from steam supply pipes 25, 27. By this method, the steam is sprayed to the whole of the protruding molds 9, 10 and the non-molding surfaces 160, 170 of the recessed molds 16, 17. As mentioned above, by spraying steam to the protruding molds 9, 10 and the recessed molds 16, 17, the protruding molds 9, 10 and the recessed molds 16, 17 are rapidly heat-exchanged by respective heat exchange elements 29 to be rapidly raised in temp. to foam a material. The sprayed steam is discharged out of the chambers as drain from discharge pies 26, 28. Subsequently, cooling water is sprayed from nozzles 15, 24 to quench the protruding molds 9, 10 and the recessed molds 16, 17 and a resin molded product is solidified.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a styrene foam molding machine that can accelerate heating and cooling when molding styrene foam in a mold.

[Conventional technology]

The molds for styrofoam molding machines are generally made of aluminum or copper, and are mainly manufactured by casting. These materials have very good thermal conductivity, but due to casting characteristics and mechanical strength constraints, the wall thickness of the mold is manufactured to be on the order of Ion/m. This is because casting molding uses green sand molds for boat fishing, so in these castings the molten metal is rapidly cooled by the green sand,
Because it is extremely difficult to cast thin-walled products, the current situation is that they are hardly used for thin-walled products.For example, the mold shown in Figure 1 is a green sand mold. It was molded by.

In FIG. 1, reference numeral 1.2 is a guide rod, and both shaft ends of these guide rods 1 and 2 are connected to a fixed plate 3.4.
They are fixed respectively. A slider 5.6 is slidably inserted into the guide rod 1.2. Slider 5
．． A moving chamber 7 is attached between the two. In FIG. 1, a mold clamping cylinder 8 is fixed to the fixing plate 3 on the right side. The cylinder rod 80 of the mold clamping cylinder 8 is
It is attached to the back side of the movement chamber 7 mentioned above.

The movement chamber 7 has a roughly concave cross section. For example, a double convex type 9.1
0 is installed. The above-mentioned moving chamber 7 and convex mold 9.
A nozzle holder 11 is arranged between the convex molds 9 and 10, and the nozzle holder 11 is fixed to the connecting piece 13 of the convex molds 9 and 10 by a fixing member 14. The nozzle holder 11 holds a plurality of nozzles 15.15. A total of four nozzles 15.15 are held in pairs for each convex type 9.10, but the number of nozzles can be freely selected. A nozzle 15 is also arranged in the upper part of the convex mold 9 in FIG. The nozzle 15.15 mentioned above is connected to a cooling water source not shown in the drawings, and cooling water is sprayed from the nozzle 15.15 over the entire surface of the non-molded surface 90.100 of the convex mold 9.10. . A double concave mold 16.17 is arranged opposite the convex mold 9.10, and the convex molds 9 and 10 are slid onto the concave mold 16.17 by a slider 5.6, and the respective molds are A Styrofoam molded product is formed by fitting it inside. The concave mold 16,17 is fixed in a fixed chamber 18, which is connected to the guide rod 1.
It is fixed to the fixing member 19.20 fixed to 2. The concave molds 16 and 17 have two holes for extruding the molded product.
A set of ejector pins 21 and 22 are provided so as to be freely removable and removable.

A nozzle holder 23 similar to that described above is disposed within the fixed chamber 18, and a plurality of nozzles 24 are held therein. These nozzles 24 are connected to a cooling water source, and as before, cooling water is sprayed over the entire surface of the non-molded surface 160, 170 of the concave mold 16, 17 as required.

Furthermore, a steam supply pipe 25 and a discharge pipe 26 are provided at the upper and lower ends of the moving chamber 7 in FIG. 1, respectively, and the steam supply pipe 25 is connected to a steam supply source not shown in the drawing. The steam sprayed from the steam supply pipe 25 heats the entire non-molding surface 9o1100 of the convex mold 9.10, and the discharge pipe 26
It is discharged as drain. Similarly, the fixed chamber 18 is also provided with a steam supply pipe 27 and a discharge pipe 28.
is heated and discharged as drain from the discharge pipe 28.

In the above-mentioned apparatus, the moving chamber 7 is moved to the left in FIG. 1 by the cylinder rod 80 of the mold clamping cylinder 8, and the molding surface of the convex mold 9.1° is moved to the concave mold 16.
17, molding material is injected into the mold as usual, and the steam supply pipe 25
Steam is sprayed into the moving chamber 7 and the fixed chamber 18 from the steam supply pipe 25, respectively.

In this way, steam is transmitted to convex 9, lO and concave 16.
By spraying onto the non-molding surfaces 90.100 and 160.170 of 17, the respective molds are heated and the material injected into the molds is foamed. The atomized steam becomes a drain and is discharged from the respective chambers through discharge pipes 26 and 28. Next, the cooling water is poured from the nozzle 15.24 into the convex mold 9.
．． 10 and the non-molding surfaces 90, 100 and 160, 170 of the concave molds 16, 17, respectively, and rapidly cooled,
Solidify the foamed resin molded product. Therefore, the moving chamber 7 is moved in the opposite direction to the recessed mold 16, 17.
The convex mold 9.10 was released from the inside, and the molded product was ejected from the inside of the concave mold 16.17 using ejector bins 21 and 22 to form a styrene foam molded product 25.250.

[Problems to be Solved by the Invention] However, in the above-described apparatus, the convex and concave non-molding surfaces, that is, the surfaces on which steam or cooling water is sprayed, are formed as smooth surfaces, and the mold itself is also thick. Because the molded surface was molded, the sprayed steam or cooling water quickly drained away from the unmolded surface. Therefore, there is a problem that the heat exchange efficiency with respect to the mold is extremely poor, and it is necessary to spray a large amount of steam or cooling water onto the non-molding surface over a long period of time. Furthermore, although large amounts of steam and cooling water are used, the heat exchange efficiency is extremely low, which has a large effect on cycle time.

The inventor continued his research by noting that if the time required for heating and cooling, which is the biggest bottleneck in this type of molding cycle, could be shortened, the number of shots per hour could be greatly improved. As a result, we succeeded in developing a molding machine that can minimize the amount of steam and cooling water used when molding expanded polystyrene in a mold, and can significantly increase the number of shots per hour.

The object of the present invention is to provide a polystyrene foam with heat exchange elements provided on the convex and concave non-molded surfaces to shorten the time required for heating and cooling, thereby significantly increasing the number of shots per hour. We provide molding machines for

Another object of the present invention is to provide a molding machine for foamed polystyrene that enables the manufacture of heat exchange elements easily.

[Means to be solved by the invention]

A molding machine to achieve the above purpose is one that heats and cools Styrofoam when molding it in a mold, and promotes heat exchange of heating and cooling with the non-molding surface of the mold. It is equipped with a heat exchange element for

It is preferable that the heat exchange element is formed into a fin shape, a convex shape, or a rod shape.

Preferably, the heat exchange element is formed on the entire non-molding surface of the mold.

[Effect]

The moving chamber to which the convex mold is fixed is moved in the direction of the concave mold fixed to the fixed chamber by pushing out the cylinder rod of the clamping cylinder. Then, the convex mold of the moving chamber is fitted into the concave mold of the stationary chamber. At the same time, a molding material is injected into the mold in the usual manner, and steam is sprayed onto the entire non-molded surfaces, that is, the outer surfaces of the convex and concave molds.

By spraying on convex and concave non-molded surfaces,
The steam is heat exchanged by a heat exchange element to rapidly raise the temperature of each mold.

Therefore, the foaming action of the material is promoted.

Next, cooling water is sprayed from the cooling water supply nozzle onto each of the convex and concave heat exchange elements to exchange heat, rapidly cooling the convex and concave types, and solidifying the resin molded product. Thereafter, the movable chamber is moved in a direction away from the fixed chamber to release the convex mold from the concave mold, and the molded product is ejected from the concave mold by an ejector pin to form a Styrofoam molded product.

〔Example〕

The embodiments of the present invention shown in FIGS. 2 to 4 will be described in detail below.

The molding machine according to the invention is the same as that shown in FIG. 1, except for the heat exchange element formed on the non-molding surface of the mold. Therefore, parts that are the same as those in FIG. 1 are given the same numbers, and the structure will be described schematically.

Both axial ends of the guide rod 1.2 are fixed to a fixed plate 3.4. Slider 5.6 on guide rod 1.2
is a slidable insert. A displacement chamber 7 is mounted between the sliders 5,6.

Cylinder rod 80 of the mold clamping cylinder indicated by numeral 8
is attached to the movement chamber 7 described above.

The movement chamber 7 has a roughly concave cross section.

For example, a double convex type 9.10
is a fixture. Transfer chamber 7 and convex mold 9.1 as described above
A spray holder 11 is arranged between the fixing member 1 and the connecting portion 13 of the convex shape 9.10.
It is fixed at 4. The spray holder 11 holds a plurality of nozzles 15. In FIG. 1, the nozzle 15 is also arranged in the upper part. Nozzle 15 above
．． 15 is connected to a cooling water source (not shown), and cooling water is sprayed from a nozzle as necessary.

Opposed to the convex mold 9 and 10 is a double concave mold 16.
．． 17 is arranged, and the convex mold 9.17 is placed in the concave mold 16.17.
10 are respectively fitted, and a Styrofoam molded product is molded in the usual manner. The recess 16.17 is fixed in a fixing chamber 18, which is held in a fixing member 19.20. The fixing member 19.20 is fixed to said guide rod 1.2. A set of two ejector pins 21.2 are installed in the concave mold 16.17.
2 is provided so that it can be freely entered and exited. Said fixed chamber 18
A nozzle holder 23 similar to that described above is arranged inside, and a plurality of nozzles 24 are held in this. Cooling water is sprayed from these nozzles 24, 24 as needed. 2
5 is a steam supply pipe and 26 is its discharge pipe.

Similarly 27 is the steam supply pipe and 28 is its discharge pipe.

In the present invention, the heat exchange element 29 is formed on the non-molded surfaces 90.100 and 160.170, that is, the outer surfaces, of the convex mold 9.10 and the concave mold 16.17.

The heat exchange element 29 is preferably an element as shown in FIGS. 3 to 5, for example.

In the heat exchange element 29 shown in FIG. 3, for example, a plate-shaped element 29 is molded onto a non-molded surface 90 of the convex mold 9. In the case of this plate-like element 29, it is formed to have the wall thickness within the possible range using a green sand mold.

In the case shown in FIG. 4, the heat exchange element 29 shown in FIG. 3, which is as thick as possible, is cut into a thin layer using an end mill or a circular saw. That is, a thin plate-shaped, rod-shaped, or fin-shaped heat exchange element 29 is formed from a thick element as shown by the dashed line in FIG. 4, for example, by end milling.

Furthermore, the heat exchange element 29 shown in FIG. For example, a thin heat exchange element 29 similar to that shown in FIG. 3 is formed by slitting with a circular saw.

Then, the moving chamber 7 is moved to the left in FIG. 1 by the cylinder rod 80 of the mold clamping cylinder 8,
Fit into the concave mold 16.17, inject the molding material into the mold as usual, and connect the steam supply pipe 25.27.
Steam is sprayed into each chamber 7.23. Then, the steam is convex 9.10 and concave 1
Steam is sprayed over the entire non-molding surface 160, 170 of 6.17. In this way, by spraying the convex mold 9.10 and the concave mold 16.17, the convex mold 9.10 and the concave mold 1 are sprayed by the respective heat exchange elements 29.
6.17 is rapidly exchanged with heat, each mold is quickly heated up, and the material is foamed. The atomized steam becomes a drain and is discharged out of the chamber from the discharge pipes 26,28. Next, cooling water is sprayed from the nozzle 15.24 to rapidly cool the convex mold 9.10 and the concave mold 16.17, thereby solidifying the resin molded product. Therefore, the moving chamber 7 is moved in the opposite direction and the concave mold 16.1 is moved.
The convex mold 9.10 is released from the inside of the mold 7, and the molded product 25.250 is released from the concave mold 16 using the ejector pins 21 and 22.
．． Styrofoam molded product 25.2 protruding from inside 17
50 is molded.

〔Effect of the invention〕

The present inventor conducted an experiment in which a polystyrene foam product was molded in one cycle process (24 processes) using the conventional mold shown in FIG. 1 and the mold of the present invention shown in FIG. According to the experimental results, there was a significant difference between the conventional mold and the mold of the present invention in the heating and cooling processes. That is, the time required for heating and cooling is as shown in Table 1 for the experimental results for the conventional mold shown in Figure 1, and for the experimental mold for the mold of the present invention shown in Figure 2. The results are shown in Table 2.

Satojin Conventional mold flea Table 1 Mold according to the present invention Note that in the above table: Exhaust 1 means that during molding, cold air initially remains in one chamber; is in a cold state.

Therefore, when steam is blown into these, the steam is immediately cooled and becomes drain. However, the drain valve is opened until the temperature of the chamber and mold rises.
This is the process of draining condensate and continuing to blow steam into it.

Exhaust 2 refers to the preheating process of the other chamber.

Cooling by cooling means that when cooling water is sprayed onto the non-molding surface of the mold, the cooling water does not properly cover the entire surface of the mold, leaving a high temperature area. In addition, the flesh pressure of molded products is not constant,
There are thin parts and thick parts, so if you leave these uneven conditions until the heat on the mold surface is equalized by heat conduction, or until the heat in the thick part of the product is dissipated. It means to leave something alone.

Vacuum cooling is a process using a vacuum pump installed in the molding machine.
After spraying the cooling water, the vacuum pump is activated to reduce the pressure inside the chamber. Then, since the water (attached to the mold surface) evaporates even at temperatures below 100°C, this means that the heat of vaporization is used to cool the mold.

Cycle time refers to the time required to complete all steps in one cycle.

Therefore, in the case of the conventional molding machine shown in Table 1, the cycle time is 151 seconds, so the number of shots per hour is 3600 seconds/(1 hour) ÷ 151 seconds = 23.84 shots/hour. becomes.

On the other hand, in the case of the molding machine according to the present invention shown in Table 2, the cycle time is 74 seconds, so the number of sheets per hour is 74 seconds. ! -/) The number is 3600 seconds/(1 hour) ÷ 7
4 seconds = 48 times/hour.

As is clear from this comparative experiment, the molding machine of the present invention can significantly shorten the time required for heating and cooling processes.
Therefore, it was confirmed that the number of shots per hour was more than doubled.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram of a conventional foamed polystyrene mold device; FIG. 2 is a cross-sectional explanatory diagram of a foamed polystyrene mold device of the present invention; FIGS. 3 to 5 are diagrams showing different heat exchange elements. FIG. 2 is a partial cross-sectional view showing an example. Explanation of symbols 10.11...Convex type 18.19...Concave type 17.27...Non-molded surface 33...Heat exchange element

Claims (3)

[Claims] (1) In a device that heats and cools Styrofoam when molding it in a mold, it must be equipped with a heat exchange element to promote heating and cooling heat exchange with the non-molding surface of the mold. Styrofoam molding machine featuring: (2) The styrene foam molding machine according to claim 1, wherein the heat exchange element is formed in a fin shape, a convex shape, or a rod shape. (3) The styrene foam molding machine according to claim 1, wherein the heat exchange element is formed on the entire non-molding surface of the mold.