JPS61175010A - Molding method - Google Patents

Abstract

PURPOSE:To make it possible to produce an article in a single molding step, which article is required to have rigidity and softness, by heating and pressing at least two types of fluid thermosetting materials that will result in different rigidities after being molded. CONSTITUTION:An SMC7 that will exhibit a low rigidity and a softness after being molded is placed on the top surface of a bottom force 6, and SMC's 8 that will exhibit a high rigidity after being molded are placed approximately on the middle of the SMC7. A top force 5 is lowered, and the forces 5, 6 are mated with the peripheries of the top and bottom forces 5, 6 closed and are pressed and heated. As a result, while the SMC's 8 are spread and they are fluidified to cover all the upper surface of the SMC7, and the SMC's 7, 8 continue to be fluidified in the cavity defined by the forced 5, 6. This state is allowed to continue for about 1-3min to set the SMC's 7, 8, so that a face panel 3 in conformity with the molding configuration of the faces 5, 6 is formed. As both the SMC's use an unsaturated polyester resin as a base, the opposed surfaces of the SMC's use an unsaturated polyester resin as a base, the opposed surfaces of the SMC's are mutually melted after the molding, thereby they are joined integrally.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molding method for obtaining a molded article using a thermosetting material.

Various parts used in vehicles, houses, etc. are often required to have both high rigidity and flexibility. For example, a vehicle's fender panel forms part of the vehicle body, so it must be rigid enough to not easily deform. Since mud and other objects will hit the panel, it is desirable to make the inner surface of the panel soft to improve its cushioning function. In order to meet such demands, conventional methods have been to construct a single part by bonding a high-rigidity member and a soft member, or to create a part with both rigidity and softness by spraying a material for a soft material onto a high-rigidity member. It was composed. However, if parts are manufactured using this method, the number of manufacturing steps will increase, leading to an increase in costs.

An object of the present invention is to provide a molding method that eliminates the above-mentioned conventional drawbacks and can manufacture articles such as parts that require both rigidity and flexibility by one molding process.

The present invention proposes a molding method in which an integral molded article is obtained by heating and pressurizing at least two types of fluid thermosetting materials having different rigidities after molding.

Big Arashi Father-in-law Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a truck, where 1 is a vehicle body, 2 is a tire, 3 is a fender panel forming a part of the vehicle body, and 4 is a splash board fixedly connected to the rear of the fender panel 3.

FIG. 2 is an exploded perspective view of the fender panel 3 and splashboard 4, and the fender panel 3 shown here is
For the reasons explained above, the inner surface 3a on the tire side needs to have softness, and the outer surface 3b needs to have high rigidity.

Such a fender panel 3 is manufactured by the method according to the present invention as follows.

FIG. 3 shows a compression molding machine for carrying out the method of the present invention.
It has an upper mold 5 and a lower mold 6 which are heated by. During molding, a flowable thermosetting material is placed on the lower die 6. Such materials include, for example, sheet molding compounds.
cornpound (hereinafter referred to as SMC) is used,
In this case, two types of SMC with different rigidities after molding are used.

That is, the first SM exhibits low rigidity and softness after molding.
C7 is placed on the upper surface of the lower mold 6 as shown with diagonal lines in FIG.
For example, a suitable number of second SMCs 8, which exhibit high rigidity after molding, are stacked and placed approximately in the center on top of the 70 to 80% portion. After that, the upper mold 5 is lowered, and the upper mold 5
．． 6 in a sealed state and put both together to make one SMC7,
Compress and heat 8. As a result, the second SMC 8 first flows while being stretched and overlaps the upper surface of the first SMC 7, and then both SMCs 7, 8 flow in the cavity of the mold 5.6. By continuing this state for about 1 to 3 minutes, the SMCs 7 and 8 are cured.

It is molded into a form corresponding to the molding surface shapes of the molds 5 and 6, that is, into the form of the fender panel 3 shown in FIG. SMC
Since these are both based on unsaturated polyester resin, the interface between both SMCs 7 and 8 becomes compatible after molding, and the two are integrally joined.

When released from the mold after molding, a soft inner surface 3 made of the first SMC 7 is formed.
A fender panel 3 having a highly rigid outer surface 3b made of a second SMC 8 and a second SMC 8 is obtained.

The general-purpose SMC that is currently widely used becomes a rigid body after molding, so it is sufficient to use this general-purpose SMC as the second SMC8, and the first SMC that remains flexible even after molding.
7, for example, Flex200 manufactured by Budd in the United States.
A flexible SMC such as 0 (product name) can be used.

The method according to the present invention can be employed to manufacture various articles other than fender panels, and the splash board 4 shown in FIGS. 1 and 2 can also be manufactured according to the present invention. The splash board 4 shown here consists of a base part 4a fixed to the fender panel 3 and a hanging part 4b below the base part 4a.The base part 4a is relatively small because the board 4 itself needs to be fixed and supported by the fender panel 3. It is necessary to have high rigidity, and conversely, the hanging portion 4b needs to have flexibility so that it can be easily deformed even if it is hit by a foreign object while the vehicle is running. Further, the tire-side inner surface 4c of the base portion 4a has flexibility, similar to the fender panel 3.

The splash board 4 as described above can be easily manufactured as shown in FIG. That is, in the lower mold 6 of the compression molding machine,
A first SMC7 that exhibits softness after molding is placed, and on one side X1 above it, another first SMC7a that also exhibits softness after molding is placed, and the other side X2 has rigidity after molding. If the upper and lower molds 5.6 are placed together and molded as in the case of FIG. 3, the splash board 4 shown in FIG. Type 6 X
In the part indicated by l, there is a first SMC that exhibits softness after molding.
Since only 7 and 7a are placed, a flexible hanging part 4b is formed from them, and the SMC 7° 8 placed on the part indicated by X2 of the mold 6 has the shape shown in FIG. As in the case, the inner surface 4c is formed to be soft, and the outer surface 4d is formed to have a rigid base 4a. In this way, it is possible to manufacture the splash board 4 having both hard and soft properties in each part by one molding. Conventionally, in order to manufacture a splash board as shown in Fig. 2, it was necessary to manufacture the base and the hanging part as separate molded products and connect them with screws, etc., but by adopting the method according to the present invention, Such work is completely unnecessary.

A second SM indicating rigidity after molding is placed on the upper surface of the lower mold of the compression molding machine.
Of course, it is also possible to place C and the first SMC on top of it, and also to place three or more types of SM with different rigidities after molding.
It is also possible to obtain molded products using C. It is also clear that the manner in which SMCs with various properties are placed in the mold may be adopted in various ways depending on the form, properties, etc. of the molded product to be obtained. In addition, as a thermosetting material with fluidity,
Bulk molding compound, usually called BMC, is not sheet-like like SMC, but is in the form of a block.
) can also be used.

According to the present invention, it has become possible to obtain an article in which each part has different hardness and softness properties by one molding.

[Brief explanation of drawings]

FIG. 1 is a side view showing a truck having parts that can be manufactured by the method according to the invention, FIG. 2 is a perspective view showing some parts of the truck exploded, and FIGS. FIG. 2 is an explanatory diagram showing a molding machine to be used and the state of use thereof. Applicant Hino Motors Co., Ltd. Figure 1 Figure 2 WIS diagram

Claims (1)

[Claims] A molding method characterized in that at least two fluid thermosetting materials having different rigidities after molding are charged into a mold and heated and pressurized to obtain an integral molded product.