JPH047287B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for foam-filling a liquid foamable material such as foamable polyurethane into a space of a target structural member or the like.

(Prior Art) Liquid foamable materials are injected and foam-filled into spaces within various structural members such as automobile bodies for various purposes such as reinforcement and heat insulation.

However, when the liquid foamable material is simply injected into the spaces within various structural members and foamed, if there is a gap in the structural member, a problem arises in that the liquid foamable material flows out from the gap. In order to avoid such problems, in the past, structural members were prepared in advance by leaving a section for air to escape during foaming, and sealing the remaining gaps using cellophane tape, or by making structural members with no gaps in advance. They used the ones that had been finished in the following. Therefore, the work efficiency is poor, and if the liquid foamable material leaks during work, the work environment deteriorates. For the above-mentioned reasons, it has been difficult in the conventional method to foam-fill a member with a partial gap with a liquid foamable material.

(Object of the Invention) The present invention is intended to solve the above-mentioned problems of the prior art, and its purpose is to form a liquid foam into a structural member of any shape without requiring complete sealing with a sealant or the like. The purpose of the present invention is to provide a method for easily foam filling a plastic material.

(Structure of the Invention) That is, the method for filling a foam according to the present invention involves inserting into the internal space a bag that expands in accordance with the shape of the internal space of the structural member or the like to be filled when the foamable material is foamed; The method is characterized in that a predetermined amount of liquid foamable material is injected into the bag and foamed.

The bag used in the present invention is preferably one that is stretchable, such as rubber, and is pushed by the foaming pressure of a foaming material to completely fill the space to be filled, but such a bag is not necessarily used. It doesn't have to be. In other words, the bag may be sized in advance to fill the entire space.

The bag body can be made of rubber, polyethylene,
It may also be made of plastic such as polypropylene. The shape, size, etc. of these should be optimally selected depending on the place of use, filling amount, type of foamable material, etc. Of course, a material that is not dissolved by the foamable material or has sufficient thickness is used.

The bag may or may not be torn during foaming. Furthermore, if the outer surface of the bag is coated with a heat-adhesive adhesive or the like, if necessary, the foam can be more firmly fixed within the structural member by heating after foaming.

After the liquid foamable material is poured into a bag-like container, it is sealed with a clip or the like and placed inside a structural member, and left for a while to foam or heated if necessary. The bag-shaped container is not torn until foaming progresses and the liquid foamable material becomes highly viscous and no longer flows out through the gaps between the structural members. Thereafter, when the bag is opened and foaming is continued, the liquid foamable material completely solidifies into a foam and fills the inside of the structural member, completing the filling.

(Example) The present invention will be explained in further detail in the following example. Note that the present invention is not limited to the following examples.

The figure is a partially cutaway perspective view of a structural member illustrating the method of the invention.

A balloon 55 made of natural rubber was attached as a bag to the injection end of the injection tool 4 in a structural member consisting of a flat panel 1 and a U-shaped panel 2 and having a component mounting hole 3 on the U-shaped panel 2. The material was inserted through the injection port 6. After injecting the liquid foamable polyurethane raw material through the injection tool 4, the mouth of the balloon 5 was sealed with a clip, and the balloon 5 was separated from the injection tool and placed inside a structural member. When foaming started and the viscosity reached such a level that it would not flow out from the gap, the balloon 5 was burst with a needle. When foaming was continued, the entire structural member was filled with foam.
The method of the present invention was able to significantly reduce the irritating odor of isocyanate compounds in the working environment compared to conventional methods.

(Effects of the Invention) As described above, the foam filling method of the present invention involves placing a liquid foamable material in a stretchable bag-like container, inserting it into a structural member, and foaming it until it reaches an appropriate viscosity. Since there is no need to seal gaps and holes in structural members, and no materials are required for this purpose, it is effective in greatly increasing work efficiency and reducing material costs. Furthermore, since the diffusion of the liquid foamable material into the working environment atmosphere can be suppressed to a minimum, it has a great effect on improving the working environment.

[Brief explanation of drawings]

The figure is a partially cutaway perspective view of a structural member illustrating the method of the invention. In the figure, 1... Flat panel, 2... U-shaped panel, 3... Parts mounting hole, 4... Injector, 5... Balloon, 6... Inlet.

Claims (1)

[Claims] 1. A bag that expands to correspond to the shape of the internal space of the structural member, etc. to be filled when the foamable material is foamed is inserted into the internal space, and a predetermined amount of liquid foamable material is injected into the bag. A foam filling method characterized by foaming.