JPS61192528A - Mold device for slush molding - Google Patents

Abstract

PURPOSE:To permit to regulate the temperature of a mold efficiently by a method wherein a plurality of gas heat medium blow-off nozzles for controlling the temperature of the mold is projected against the back surface of the mold an a heat-resistant shielding plate is arranged between the back surface of the mold, wherein a cavity is located, and the nozzles. CONSTITUTION:A large chamber 10 is formed between the back surface of the mold 1 and the internal wall surface of a box while a reserve tank 11, in which the heat medium for heating or cooling is stagnated temporarily, is formed in the bottom part of the chamber 10. A multitude of nozzles 12 are projected from the reserve tank 11 against the back surface of the mold with a posture capable of covering the whole of the back surface 15 of the mold substantially. Further, the heat-resistant shielding plate 16 is arranged between the back surface 15 of the mold and the nozzles 12 so that the gas heat medium, blown out of the nozzles 12, will never hit directly the back surface 15 of the mold wherein the cavity 2, corresponding to the part of the mold in which forming is not necessitated, is located.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a mold apparatus for slush molding.

The slush molding method involves molding powder or liquid into a preheated mold.
The layer material is put in, and by heating the mold, a part of the layer material is melted and adhered to the cavity surface of the mold, and then the unmolten material is discharged from the mold, leaving it on the mold surface. The process involves heating and curing the adhered material again by increasing its viscosity in a thinner form, then cooling the mold and demolding the molded product.

As a more specific example of this slush molding method, the thickness of the inner semi-rigid or soft urethane foam is 0.
．． 4-2. It is intended for molding synthetic resin skin bodies of approximately Q am.

(Prior art) As a mold for slush molding, an iron or copper pipe is generally welded to the back of a nickel electroforming mold, and a heating oil is flowed into the pipe to heat and cool the mold. It is disclosed in the publication No.-10581. In addition, there are other molds in which the wall thickness of the mold is increased and a pipe for flowing heat medium oil is embedded in the mold to improve the heating and cooling efficiency of the mold, for example, in Japanese Patent Application Laid-Open No. 59-209113. has been disclosed.

(Problem to be solved by the invention) However, with the structure of the former mold, there is distortion during the welding process of the heel, which welds pipes made of dissimilar metals such as iron or copper directly to the nickel electroforming, and penetration of the welding filler metal into the nickel occurs. Cracks may occur in the mold due to differences in linear expansion coefficients between metals, the mold may become deformed, or cracks may occur in the mold due to residual stress such as distortion generated during welding during molding. Ta. In addition, the latter type of mold necessarily requires a thicker mold to embed the pipe in the mold, which increases the weight of the mold, making it difficult to handle, and is also expensive. Become something.

Furthermore, in these heating and cooling systems using heating medium oil, two types of heating medium and cooling medium are circulated in separate closed circuits, so the equipment for this closed circuit is large-scale system-intensive. This results in expensive equipment costs. Also,
It is also possible to use an electric cooler, etc. for the cooling system circuit, and to flow the heating system and cooling system into a single pipe placed in the same mold. A large amount of energy is required to return the temperature to the normal temperature, and large losses remain as a problem in terms of efficient energy use.

The purpose of the present invention is to improve the efficiency of heat treatment of molds, eliminate energy loss due to mixed flow of heat medium, and furthermore, create a slush molding mold that prevents molding material from adhering to unnecessary molding parts of the mold as much as possible. Our goal is to provide the following.

(Means for Solving the Problems) The present invention is a slush molding mold device that adjusts the temperature of a mold by spraying a heated or cooled gaseous heat medium, and the first invention is a mold box. A mold for molding is inserted into the box from the back side, and a plurality of gaseous heat medium blowing nozzles for controlling the mold temperature are protruded from the chamber part formed in the box toward the back of the mold. The second invention is characterized in that a heat-resistant shielding plate is disposed between the nozzle and the back surface of the mold where the cavity surface corresponding to the unnecessary molding portion of the skin of the mold is located. In place of the heat-resistant shielding plate, a plurality of nozzles for ejecting heat medium for cooling are arranged on the back side of the mold where the cavity surface corresponding to the unnecessary molding portion of the skin of the mold is located. Both of these were proposed with the intention of clearly dividing the heating and cooling zones of the mold.

(Function) In the first invention, when the heating gaseous heat medium for raising the temperature of the mold is blown out from the nozzle to the back surface of the mold almost entirely, the surface of the mold is damaged. A heat-resistant shielding plate is installed on the back side of the mold where the cavity surface corresponding to the required molding part is located to prevent the heating medium from being directly ejected to the punched part. suppressing mountains and lowering the temperature,
This prevents excess powder material from adhering to the cutout due to semi-melting. Also, in the second invention, when the heating gaseous heat medium for raising the temperature of the mold is blown out from the nozzle to the back surface of the mold almost entirely, the surface of the mold is damaged. Cooling heat medium is directly ejected only to the back of the mold where the cavity surface corresponding to the required molding part is located, suppressing the rise in temperature of the punched part, keeping the temperature low, and reducing excess waste to the punched part. Prevents adhesion due to semi-molten powder material.

(Example) Next, a specific example of the apparatus of the present invention will be described using the drawings.

FIG. 1 is a cross-sectional view of a slush molding mold device according to the present invention. In the figure, (1) is a slush molding mold, which is formed by nickel electroforming, aluminum precision casting, mold spraying, etc. The mold (1) has a cavity (2) shaped to match the formation of a predetermined skin, and an outwardly directed flange (3) is integrally formed at the opening edge of the cavity (2). Furthermore, the surface of the cavity (2) has a necessary molding equivalent part (4) and an unnecessary molding equivalent part (4) of the skin body for the purpose of molding.
5) is composed of the above two components that are in charge of molding.

Generally, unnecessary molded parts of the skin body tend to concentrate in the area near the opening of the cavity (2) or on the side surface of the cavity (2), but of course, the unnecessary molded parts may depend on the shape of the target skin body. The location of the required molded parts is highly dependent and variable.

The above-mentioned mold (1) is installed on the support piece (7) attached to the inner wall surface of the upper end of the mold box (6) via a gasket (8) made of silicone rubber or the like with excellent heat insulation effect. This mold (1) is inserted into the mold box (6) from the back side of the mold, and placed in such a way that the opening (9) of the mold is opened on the box (6), and the mold A large chamber αQ is formed between the back surface of the box and the inner wall surface of the box, and a storage tank OD for temporarily retaining a heating and cooling medium is formed at the bottom of the chamber 01. A large number of nozzles (2) are installed toward the back of the mold in a manner that covers almost the entire back surface of the mold.
stands out.

In the molding device with the above configuration, the cavity surface of the mold (1) is responsible for the necessary molding portion (4) and the unnecessary molding portion (5), respectively, depending on the shape of the skin body desired to be molded. The area to be processed is divided into υ, of which it is necessary to control the heat supply to the unnecessary forming part (5) from the necessary forming part (4). Therefore, in the mold apparatus shown in Fig. 1, the entire area of the unnecessary molding equivalent part (5) or the almost entire area near the necessary molding equivalent part (4) is located one step lower than the cavity surface of the necessary molding equivalent part (4). A recess is provided, and the entire surface of this recess is covered with a heat-resistant cover plate αJ made of polyimide resin with excellent heat insulation properties, the same resin reinforced with glass fiber, or fluororubber. A cavity α→ is formed in the entire area or substantially the entire area of the unnecessary molded portion (5) in order to obtain a further heat insulating effect.

Furthermore, in the mold apparatus shown in FIG.
) A heat-resistant shielding plate 0Q is installed between the back surface of the mold and the nozzle O2 to prevent the gas, which is a heating medium, blown from One end of the shield plate is fixed to the back surface of the support piece (7).

Since FIG. 2 shows another embodiment of the slush molding mold device according to the present invention, the cooling medium is used in the unnecessary molding portion of the mold in place of the Aoi shielding plate αQ used in FIG. (5) A nozzle α force is provided for spraying only on the back surface 0υ. Immediate ζ mold box (6)
The chamber part 00 is equipped with a base pipe (to) that branches into a plurality of, for example, bifurcated shapes, in the chamber part, and from this pipe (to), there is a back surface of only the unnecessary molding portion (5) of the mold. Toward the part αυ, the back part of this mold is 0! The nozzle αη protrudes in such a manner as to cover substantially the entire surface of the nozzle '9.

For example, a water spray is flowing in this base pipe αQ.

The apparatus constructed from the combination of the mold (1) and the mold box (6) described above has a powder material supply device, an example of which is shown in FIG. 3, to charge and fill the mold with powder material. That is, in this supply device, a mold box is rotatably mounted on the upper part of the support frame (1) on a frame having a pair of left and right support frames (1). Below the mold box (6), a reservoir tank (c) is installed in the frame that can be raised and lowered by a lifting machine (a), and nozzles are installed at a predetermined pitch in the opening 9 of the reservoir tank (to). (c) A plurality of compressed air supply pipes (1) protruding from a group are connected to the reservoir tank (c)
A louver (not shown) is arranged in the longitudinal direction of the reservoir tank and is located closer to the inside of the reservoir tank than the air supply pipe (a) for controlling the input or discharge of the powder material contained in the tank (c). is set up.

Rotate the mold box (6) equipped with the mold (1) by 180 degrees around the support shaft @Kan so that the opening 09 of the mold faces downward, and activate the lifting machine for the reservoir tank (C). The mold box (6) is raised to the position, and the reservoir tank (6) and the opening 09 of the mold (1) are brought into close contact, and both are combined and fixed. The combined mold box (6) and reservoir tank (c) rotate 180 degrees around the support axis of the mold box (6) @(a), and are now located at the upper position 7? The louver of the l-IJ reservoir tank (c) is opened, and the powder material in the reservoir tank (c) is thrown into the υ mold (1) by its own weight, and then taken into the mold box (6) and placed in the reservoir tank (c). is 1
After rotating 80 degrees in the opposite direction and returning to the original position, the combination of the mold box (6) and the reservoir tank (c) is released, and only the reservoir tank (c) is lowered.

When molding, for example, the skin of an automobile instrument panel pad using a powder material such as vinyl chloride resin in the slush molding mold apparatus having the above configuration, the powder material is first charged into the mold, and then the nozzle (2 ), and by heating the nozzle (2) after filling the powder material, the part (4) corresponding to the required molding of the skin of the mold is heated. The part of the powder material that is in contact with the inner surface of the cavity is semi-molten, which gives rise to adhesive properties, the original material is attached to the inner surface of the mold, and the unnecessary part of the powder material that is not semi-molten is discharged from the mold. However, this unnecessary molding part of the finger mold occurs when the mold is preheated or heated, and in the first invention, the shielding plate prevents the heating from being blown out toward the back of the mold. This prevents the direct injection of the gas into the back of the mold, suppresses the temperature rise in the part of the mold that corresponds to unnecessary molding, and leaves the core part in an unheated state. The material is discharged out of the mold without being semi-molten together with other unmolten excess powder material.

Also, in the second invention, during preheating or heating of the mold, the portion of the mold that corresponds to unnecessary molding is ejected from the cooling fluid ejecting nozzle disposed toward the core portion. Since the cooling medium is injected and the core is kept in a non-heated state, unnecessary adhesion of powder material can be prevented.

After that, the mold is further heated to completely melt the semi-molten material adhering to the required molding portion (4) of the skin of the mold, and then the mold is transferred to a heating gas blowing nozzle which is a pre-processing process. A cooling gas is ejected to cool the mold, and the thin skin formed on the mold cavity surface is removed from the mold. Even if a portion of the extension of the skin adheres to the unnecessary molding portion (5) of the finger mold (1), this unnecessary piece can be easily peeled off.

(Effects of the Invention) As described above, the slush molding mold device of the present invention has a structure in which jQ heat and a cooling medium are sprayed onto the back surface of the mold, so that the heating medium is brought into direct contact with the mold and the mold is heated. This makes it possible to efficiently control the temperature of the mold, and eliminates the need for any processing such as installing a pipe for passing a heat medium into the back or inside of the mold, which is required for some molds of this type.

The durability of the mold is increased, and the life of the mold itself can be extended. In addition, a concave portion is provided on the cavity surface of the mold to remove the unnecessary molding portion of the mold skin, and a heat-controlling cover plate is used to block the core portion from forming a rupture zone.
It is possible to prevent excess powder material from adhering to the above-mentioned unnecessary molding portions, thereby making it possible to reliably discharge excess material from within the mold, and ensuring efficient use of material without waste. These results will ultimately lead to a reduction in product costs.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a slush molding mold device embodying the present invention, Fig. 2 is a view corresponding to Fig. 1 showing another embodiment, and Fig. 3 is a sectional view of a mold device for slush molding according to the present invention. FIG. 1 is an overall perspective view of a supply device for supplying materials. In the figure, (1) is the mold, (2) is the cavity, and (4) is the mold.
) is the necessary molding equivalent part of the skin body, (5) is the unnecessary molding equivalent part of the skin body, (6) is the mold box, aO is the chamber, α2 is the nozzle for gaseous heat medium Suita, and Q3 is the heat control cover plate. , 0→ indicates a cavity, QO indicates a back surface of the mold, Qe indicates a heat-resistant shielding plate, and αη indicates a cooling medium jetting nozzle.

Claims (4)

[Claims] (1) A slush molding die is inserted into the mold box from the back side, and the chamber part formed inside the box has multiple gas gases for controlling the mold temperature towards the back side of the mold. Slash molding in which a heat medium blowing nozzle is protruded, and a heat-resistant shielding plate is installed between the nozzle and the back of the mold where the cavity surface corresponding to the unnecessary molding part of the mold skin is located. mold equipment. (2) A heat-insulating cavity is formed below the cavity surface of the unnecessary molding portion of the skin of the mold by covering the surface with a heat-resistant cover plate. Mold equipment for slush molding. (3) A slush molding die is inserted into the mold box from the back side, and the chamber part formed inside the box has multiple gas gases for controlling the mold temperature towards the back side of the mold. A slash in which a plurality of nozzles for blowing out heat medium for cooling are arranged only on the back side of the mold where the cavity surface corresponding to the unnecessary molding part of the skin of the mold is located. Molding mold equipment. (4) The lower part of the cavity surface of the unnecessary molding portion of the skin of the mold is formed with a heat-insulating cavity whose surface is covered with a heat-resistant cover plate. Mold equipment for slush molding.