JPH059672B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flexible hose used as a pressure-resistant hose for compressed air or the like.

[Conventional technology and its problems]

Conventionally, this type of flexible hose has been constructed by winding reinforcing wire 2 spirally around the outer circumferential surface of an inner tube 1 made of soft synthetic resin at appropriate pitches, as shown in FIGS. 4 and 5. It has a structure in which a reinforcing wire 2 is covered with an outer tube 3 made of soft synthetic resin. By the way, when the reinforcing wire 2 is wound around the outer circumferential surface of the inner tube 1 at appropriate pitches using a coil forming machine, the tension of the wire 2 stretches the outer circumferential surface of the inner tube between the pitches of the reinforcing wire 2. has the characteristic of being forcibly deformed to bulge slightly outward. Therefore, when this flexible hose is used by being bent into an irregular shape such as a bend, the compressive stress generated on the curved inner surface causes the bulging deformed portion 1
00 further protrudes outward in a lump, and this lump 10
1 is susceptible to external damage during use, and there is a risk of internal air leakage (Figure 6).

[Problem that the invention seeks to solve]

The problem to be solved by the present invention is to prevent the outer circumferential surface of the inner tube between the pitches of the reinforcing wire from bulging outward, so that when the inner tube is bent into an irregular shape such as a bend, the lump portion is removed from the outside. The goal is to prevent this from occurring.

[Means for solving problems]

Technical measures taken to solve the above-mentioned problems are to form a constricted part with a reinforcing thread tightened in a spiral manner in the valley of the inner tube between the pitches of the reinforcing wire.

Examples of the reinforcing wire include a metal wire coated with a soft synthetic resin and a hard resin wire.

Further, as the reinforcing thread, metal thread or hard resin thread is used.

[Effect]

According to the technical means of the present invention, the shape drawing part forms a V-shaped wall part projecting inward of the pipe, with the reinforcing thread tightening part being the lowest part, on the inner pipe wall part between the pitches of the reinforcing wire.

Therefore, due to the compressive stress that occurs when the V-shaped wall is bent into an irregular shape such as a bend, both inclined walls of the V-shaped wall are bent toward each other with the reinforcing thread tightened part as the center, and are bent toward the inside of the pipe. protrude to

〔Effect of the invention〕

As described above, in the present invention, the shape-drawn part is formed in the valley part of the inner tube between the pitches of the reinforcing wire with the reinforcing thread that is tightened in a spiral manner, so that it can be bent and used in irregular shapes such as bends. The resulting compressive stress acts into the inner tube at the constricted portion, forms a lump within the inner tube, and does not protrude outward as a lump as in the conventional case. Therefore, durability can be improved without external damage, and the external shape is beautiful.

〔Example〕

An example of an embodiment of the present invention will be described below based on the drawings.

The hose of the present invention includes an inner tube 1 made of soft synthetic resin,
A reinforcing wire 2 wound spirally around the outer circumferential surface of the inner tube 1, the reinforcing wire 2, an outer tube 3 made of soft synthetic resin covering the inner tube 1, and the reinforcing wire 2
The reinforcing thread 4 is tightened spirally around the outer circumferential surface of the inner tube 1 between the pitches of the inner tube 1.

The inner tube 1 is formed into a tube shape by extruding a soft synthetic resin material using an extrusion method.

The reinforcing wire 2 is a metal wire 12 covered with a soft synthetic resin film 2.
2 or made of hard synthetic resin, and after the inner tube 1 has hardened, it is wound spirally around the outer circumferential surface of the inner tube 1 using a coil forming machine or the like at appropriate pitches to form the inner tube. Adds pressure resistance to 1.

The reinforcing thread 4 is a metal thread or a hard resin thread, and is formed into the inner tube between the pitches of the reinforcing wire 2 while applying tension using a desired device or method such as a coil forming machine similar to the above-mentioned reinforcing wire 2. 1 valley part 1
A is tightened in a spiral manner to form a diameter-restricted portion 5.

The diameter narrowing portion 5 is formed by forming a V in the inner pipe wall portion between the pitches of the reinforcing wire 2 with the tightening portion of the reinforcing thread 4 as the lowest part.
The shaped wall portion 5a is formed to protrude toward the inside of the tube, and the outer circumferential surface of the inner tube 1, the reinforcing wire 2, and the reinforcing thread 4 are connected to the outer tube 3, respectively.
The compressive stress that occurs when the V-shaped wall portion 5a is covered with the tape and used in a bent shape as shown in FIG. Wrinkles are formed in the inner tube 1 by concentrating them in a direction approaching each other, so that no lumps are formed on the outside.

The outer tube 3 has the function of sealing the outer peripheral surface of the inner tube 1, the reinforcing wire 2, and the reinforcing thread 4, and the function of imparting strength to the hose itself, and is formed into a covering shape using a desired method such as extrusion molding. to form.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the flexible hose of the present invention, in which Fig. 1 is a front view with a partial cutaway, Fig. 2 is an enlarged view of the main parts in Fig. 1, and Fig. 3 is a plan view showing the state of use. 4 is a partially cutaway front view of the conventional example, FIG. 5 is an enlarged view of the main part in FIG. 4, and FIG. 6 is a plan view showing the conventional example in use. In addition, in the figure, 1: inner tube, 2: reinforcing wire, 3: outer tube, 4: reinforcing thread, 5: diameter constricted part.

Claims (1)

[Claims] 1. A flexible hose in which a reinforcing wire is spirally wound around the outer circumferential surface of an inner tube made of soft synthetic resin at appropriate pitches, and the inner tube and reinforcing wire are covered with an outer tube made of soft synthetic resin. A flexible hose characterized in that a diametrically constricted portion is formed in the trough of the inner tube between the pitches using a reinforcing thread that is tightened in a spiral manner.