JPS622109Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a reinforced safety gas hose with excellent cut resistance and pull-out resistance.

As incidents of gas suicide attempts by pulling out or cutting gas hoses are increasing, metal wires are buried in the gas hoses to make it impossible to cut them, and semi-permanently fixed fasteners are used. A countermeasure has been proposed in which a gas hose is connected and fixed to a gas pipe or a mounting part of a gas appliance. As this type of gas hose, one in which a gas-impermeable rubber hose is coated with a metal wire and an outer layer made of rubber or resin is further applied thereon is known. However, according to research conducted by the present inventor, if the fastener is strongly tightened, especially in those with an outer layer made of resin, compression set occurs in the tightened part, and over a long period of time, It turns out that it becomes easier to pull out. In addition, the connecting end of the gas hose is heated by the high temperature heat generated by the gas appliance, and tends to be thermally deformed, posing the risk of gas leakage or pull-out at the connecting end.
Furthermore, for hoses with an outer layer made of rubber, it is necessary to vulcanize the outer layer after molding it. However, in general, sulfur is not used as a vulcanizing agent because the work efficiency is poor and the finished product may discolor due to the reaction between sulfur and lead in the rubber. However, the mechanical strength of the finished product was insufficient due to formulation constraints such as having to vulcanize only with a vulcanization accelerator.

Therefore, the purpose of this invention is to create a fastener that causes almost no compression set even when it is strongly tightened for a long time, has good shape retention at high temperatures, and can be manufactured with high work efficiency. The object of the present invention is to provide a safety reinforced gas hose having sufficient mechanical strength.

As a result of intensive research to achieve the above-mentioned objective, the inventor of the present invention discovered that an extremely superior safety reinforced gas hose could be obtained by using a specific vinyl chloride resin as the outer layer, and came up with this idea.

Hereinafter, embodiments of this invention will be described with reference to the attached drawings.

This gas hose 1 has a tubular inner rubber layer 2 mainly made of gas-impermeable rubber. As the gas-impermeable rubber, for example, chloroprene rubber or chlorosulfonated polyethylene is used. This rubber inner layer 2 is manufactured by vulcanization molding according to a normal processing process.

The outer side of the rubber inner layer 2 is covered with a reinforcing layer 3 made of a metal wire braided into a net shape. The material of the metal wire is preferably stainless steel, for example. In addition, it is desirable that the metal wire has a thickness and shape that will not be easily cut by a knife and will provide appropriate flexibility to the gas hose.
In some cases, a strong filament made of synthetic fibers such as aromatic polyamide fibers may also be used. In this embodiment, the metal wire is braided into a net shape, but it goes without saying that it may be wound around the rubber inner layer 2 in a spiral shape.

On the outside of the reinforcing layer 3, a resin outer layer 4 made of a vinyl chloride resin containing 5 to 90% by weight of gel insoluble in tetrahydrofuran is adhered.

This vinyl chloride resin is disclosed in, for example, Japanese Patent Application Laid-open No. 80354/1983, so it will not be described in detail here, but its outline is as follows. First, the vinyl chloride resin referred to herein refers to a vinyl chloride homopolymer or a copolymer of vinyl chloride as a main component and a monomer copolymerizable with vinyl chloride. The gel component insoluble in tetrahydrofuran was extracted with hot tetrahydrofuran for 22 hours using a Soxhlet extractor.
It refers to the extraction residue separated with a 350 mesh filter, and such a gel can be obtained by polymerizing vinyl chloride and a polyfunctional compound specifically shown in JP-A-54-80354. Can be done. Further, in this invention, the resin component means a component excluding additives such as a plasticizer, that is, a resin constituent component. However, in reality, the resin component is 100%
It is preferable to use the plasticizer in an amount of 25 to 200 parts by weight based on the weight part. Such a vinyl chloride resin is produced, for example, as follows. That is, an appropriate amount of a polyfunctional compound is added to a vinyl chloride polymerization system, polymerized so that the gel content insoluble in tetrahydrofuran in the resin component is 5 to 90% by weight, and a plasticizer, heat stabilizer, etc. Additives may be added and mixed. Then, this resin outer layer 4 is formed by extruding the above-mentioned vinyl chloride resin into the reinforcing layer 3.
It can be formed by extrusion coating on the outside of.
The resin outer layer 4 made in this way has rubber elasticity, has low compression set even when fastened with fasteners for a long time, has good shape retention at high temperatures, and can be colored freely. It has excellent features such as being able to On the other hand, unlike rubber, there is no need for vulcanization, which greatly improves production efficiency.

As is clear from the description of the embodiments described above, according to this invention, even if the gas hose is strongly tightened and fixed to the gas pipe or gas appliance mounting part, it will not loosen over a long period of time, and it will not be exposed to high temperatures. It is possible to provide an excellent safety gas hose that does not easily undergo thermal deformation even when exposed to heat, can be manufactured with high work efficiency, and has improved mechanical properties.

[Brief explanation of the drawing]

The drawing is a cutaway perspective view of the essential parts of the safety-reinforced gas hose according to this invention. In the figure, 1 is a gas hose, 2 is a rubber inner layer, 3 is a reinforcing layer, and 4 is a resin outer layer.

Claims (1)

[Scope of utility model registration request] A rubber inner layer formed into a tubular shape mainly made of gas-impermeable rubber, a reinforcing layer made of a metal wire or the like coated on the outer periphery of the rubber inner layer, and a resin outer layer coated on the outer periphery of the reinforcing layer. In the gas hose, the resin outer layer is made of a vinyl chloride resin having rubber elasticity with low compression set and containing 5 to 90% by weight of gel insoluble in tetrahydrofuran in the resin component. Reinforced gas hose.