JPS607137Y2 - plastic hose - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in plastic hoses used, for example, in refrigerant transport hoses or hydraulic hoses.

Generally, when a hose with a plastic bottom is actually used, the pressure resistance of the hose itself is very low.

For this reason, some hoses are made by providing a braided reinforcing layer of natural fibers, synthetic fibers, etc. on the outer peripheral surface of the hose, and extruding an outer layer thereon.

In this case, reasons for providing the outer layer include, for example, prevention of disturbance and damage to the braided reinforcing layer, as well as the need for weather resistance, chemical resistance, and the like.

However, since the outer layer of the hose with the above structure is coated by an extrusion device, the outer layer always has a predetermined thickness. Therefore, when connecting and integrating with a hose fitting, the outer layer at the end of the hose is always removed. There are disadvantages in that the connection and integration must be performed after the process has been completed, and further disadvantages include increased costs due to additional steps, increased bending radius, decreased visibility, and excessive quality.

On the other hand, there are also plastic hoses in which the hose and a braided reinforcing layer are bonded together for the purpose of improving the kink resistance of the hose.

However, when the hose constructed as described above is used as a hose assembly at high temperatures for a long period of time, the adhesive loses weight and the fastening stress at the hose fastening portion decreases.
Due to the repeated thermal history of high and low temperatures, the internal fluid tends to leak easily.

The purpose of the present invention is to eliminate the drawbacks of the conventional technology described above, prevent internal fluid from leaking even when used repeatedly at high temperatures, and have functionality equivalent to or better than conventional technology, as well as chemical resistance, cost, and cost reduction. It is an object of the present invention to provide a plastic hose that can be improved in weight, wall thickness, flexibility, ease of attaching hose fittings, etc.

The gist of the present invention is to provide a hose comprising a synthetic resin inner layer tube made of polyamide resin, etc., with a braided reinforcing layer made of natural fibers, synthetic fibers, etc. on the outer surface, and a polypropylene resin paint between the inner layer tube and the reinforcing layer. It is a plastic hose that is characterized by being impregnated with and then painted.

The present invention will be explained below with reference to the embodiment shown in FIG.

In the figure, 1 is an inner tube made of 11 nylon, 12 nylon, polyamide resin such as copolymerized nylon, or other synthetic resin; 3 is an inner tube made of cotton, other natural fibers, or polyvinyl alcohol, polyester, polyamide, or other A braided reinforcing layer made of synthetic fiber or the like is shown, and in the present invention, a polypropylene resin paint is impregnated and painted between the inner tube 1 and the braided reinforcing layer 3.

Polypropylene resin paint is a paint made by dissolving polypropylene resin in xylene, and its resin concentration is as low as 3 to 12%.

This is because the solubility of polypropylene in xylene is 15% or less.

Here, a specific method for manufacturing the plastic shown in FIG. 1 will be illustrated.

First, the braided reinforcing layer 3 is plated on the continuously extruded synthetic resin inner layer tube 1 using an extruder. At this time, a polypropylene resin paint is prepared in advance, and The inner layer tube 1 and the reinforcing layer 3 are impregnated with the paint, either by creating a bath or by dropping it from above, so that the solution adheres to the inner tube 1 and the reinforcing layer 3.

In particular, for the coating layer 4, excess paint is wiped off immediately after impregnation to improve the appearance.

In this way, a plastic hose can be obtained through two steps: inner tube extrusion and braiding.

As shown, it may be configured to have two or more layers.

That is, in FIG. 2, 1 is a synthetic resin inner layer tube, 3 is a first braided reinforcing layer, 5 is a second braided reinforcing layer, and numerals 2, 4, and 6 are coatings impregnated with polypropylene resin paint and painted. It is a membrane.

By impregnating and painting the inner tube and reinforcing layer with polypropylene resin paint, the plastic hose of this invention forms a thin coating layer that cannot be obtained with melt-extrusion coating, resulting in chemical resistance, water absorption resistance, and permeation resistance. , flexibility, and terminal fittings are designed to improve workability and battery e-liquid resistance.

Moreover, since the polypropylene coating film of the present invention is thin, it is lightweight and can be manufactured at low cost.

As described in detail above, according to the present invention, various problems associated with conventional plastic hoses can be solved.

[Brief explanation of the drawing]

FIG. 1 is a partially vertical front view showing one embodiment of the plastic hose of the present invention, and FIG. 2 is a partially vertical front view showing another embodiment of the plastic hose of the present invention. 1...Synthetic resin inner layer tube, 2, 4 and 6
...Polypropylene resin coating layer, 3 and 5.
...braided reinforcement layer.

Claims (1)

[Scope of utility model registration request] In a hose consisting of a synthetic resin inner tube made of polyamide resin, etc., and a braided reinforcing layer made of natural fibers, synthetic fibers, etc. provided on the outer surface, a polypropylene resin paint is impregnated and painted between the inner tube and the reinforcing layer. A plastic hose featuring: