JPH0542875U - Reinforced pipe - Google Patents

Abstract

(57) [Abstract] [Purpose] Ameliorating the drawbacks of conventional reinforcing pipes in which a flat plate-like reinforcing wall along the longitudinal direction is integrally provided on the inner surface side of a hollow pipe body, and the reinforcing effect depending on the direction in which a load is applied. (EN) Provided is a reinforced pipe which has no unevenness, is uniform, and has an excellent reinforcing effect. [Structure] On the inner surface side of a hollow pipe main body 2, a reinforcing wall 3 is provided integrally with the pipe main body 2 along the longitudinal direction, and the reinforcing wall 3 is formed in a spiral shape in the longitudinal direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reinforced pipe, and more particularly to a reinforced pipe obtained by further improving a conventional reinforced pipe in which a reinforced wall is integrally provided on an inner surface of a hollow pipe body.

[0002]

[Prior Art]

 2. Description of the Related Art In recent years, synthetic poles have been widely used in place of conventional bamboo poles as flag poles, railroad crossing barrier poles, clothes poles, agricultural poles, and the like. From the standpoint of placing emphasis on lightness, these are usually hollow pipes.

In order to reinforce these hollow pipes while maintaining the lightness of the hollow pipes, as shown in FIGS. 7 and 8, a reinforcing wall 12 along the longitudinal direction is integrally formed on the inner surface side of the pipe body 11. The reinforced pipe 13 provided is known.

[0004]

[Problems to be solved by the device]

 However, the conventional reinforcing pipe 13 has a large difference in pipe strength due to the difference in the direction in which the load is applied, and although it is excellent in the reinforcing effect against the load in the width direction of the reinforcing wall 12, it particularly It is weak against a load applied in a right angle (direction of arrow a), and there is a problem that the pipe is largely bent when a load is applied from such a direction.

The present invention has been made in view of the above points, and an object of the present invention is to provide a reinforcing pipe having a uniform reinforcing effect against the difference in the direction in which a load is applied.

[0006]

[Means for Solving the Problems]

 That is, the reinforcing pipe of the present invention comprises a hollow pipe main body and a reinforcing wall integrally provided on the inner surface side of the pipe main body along the longitudinal direction, and the reinforcing wall has a spiral shape in the longitudinal direction. It is characterized by

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings.

1 to 4 show an embodiment of the reinforcing pipe 1 of the present invention. The reinforcing pipe 1 of the present invention comprises a hollow pipe main body 2 and a reinforcing wall 3 provided integrally with the pipe main body 2 along the longitudinal direction on the inner surface side of the pipe main body 2. It is formed in a spiral shape toward the direction.

The material of the reinforcing pipe 1 of the present invention includes synthetic resin, which is melted in an extruder, extruded through a die having a gap 4 having a shape shown in FIG. 5, and the extruded pipe is rotated. By taking it off while pulling it, it is possible to obtain the reinforcing pipe 1 of the present invention in which the pipe body 2 and the reinforcing wall 3 are integrally formed, and the reinforcing wall 3 has a spiral shape.

Examples of the synthetic resin constituting the reinforcing pipe 1 of the present invention include acrylic resin, polycarbonate resin, polystyrene resin, polyvinyl chloride resin, ABS resin, polyethylene resin, polypropylene resin, and the like. .. Among these, acrylic resins, polystyrene resins, polyvinyl chloride resins, polycarbonate resins, and ABS resins that can obtain a pipe having a high bending elastic modulus are preferable. Further, in order to improve the elastic modulus, a filler such as glass fiber, calcium carbonate or talc may be added if necessary.

The reinforcing effect can be enhanced as the pitch of the spiral shape of the reinforcing wall 3 becomes finer. However, if the pitch is too small, the reinforcing effect cannot be further improved and the amount of resin used increases. Not costly. The preferable pitch of the spiral shape of the reinforcing wall 3 is 3 to 12 times, especially 5 to 9 times the pipe diameter.

FIGS. 6 (a) and 6 (b) are vertical cross-sectional views of the reinforcing pipe 1 according to another embodiment of the present invention, taken along a plane perpendicular to the longitudinal direction. The reinforcing wall 3 is not limited to the case where the hollow portion 5 of the pipe body 2 is divided into two as shown in the above-mentioned embodiment, and the reinforcing wall 3 is not limited to the shape of the pipe body 2 as shown in FIGS. It is also possible to provide the hollow portion 5 in such a shape that it is divided into three.

The results of load deflection tests of the reinforcing pipe of the present invention and the conventional reinforcing pipe shown in FIGS. 7 and 8 are shown below. The load deflection test is a two-point support load deflection test in which both ends of a pipe with a length of 1000 mm are supported, and the amount of deflection of the pipe when a load of 200 g is suspended at approximately the center of the pipe is measured at the center of the pipe. Then, two types of one-sided load deflection tests were carried out, in which one end of a pipe having a length of 1000 mm was supported and the amount of deflection at the pipe tip (load suspension end) was measured when a load of 200 g was suspended at the other end.

Both the reinforcing pipe of the present invention and the conventional reinforcing pipe have a pipe outer diameter of 9 mm, a wall thickness of the pipe body and a wall thickness of the reinforcing wall of 0.9 mm, and the reinforcing pipe of the present invention is shown in FIG. A shape having a reinforcing wall pitch of 60 mm was used. In addition, the conventional reinforcement pipe was tested by supporting it so that the reinforcement wall was positioned horizontally. Table 1 shows the results of the two-point supporting load deflection test, and Table 2 shows the results of the one-side supporting load deflection test.

[0015]

[Table 1]

[0016]

[Table 2]

From the above results, the reinforced pipe of the present invention is improved in deflection by 15% in the two-point support load deflection test as compared with the conventional product, and in the one-side support load deflection test as compared with the conventional product. It was observed that the deflection was improved by 17%.

[0018]

[Effect of the device]

 As described above, in the reinforcing pipe of the present invention, the reinforcing wall integrally provided along the longitudinal direction on the inner surface side of the hollow pipe main body is provided so as to form a spiral shape in the longitudinal direction. It is possible to remedy the disadvantage of conventional reinforcement pipes that it is strong against the load applied in the width direction of the pipe but weak against the load applied perpendicularly to the reinforcing wall surface, and is even with respect to the load from any direction. It has excellent strength.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of a reinforcing pipe of the present invention.

FIG. 2 is a vertical sectional view taken along line II-II of FIG.

3 is a vertical sectional view taken along the line III-III in FIG.

4 is a vertical sectional view taken along the line IV-IV in FIG.

FIG. 5 is a schematic view showing a gap shape of a die used for manufacturing the reinforcing pipe of the present invention.

FIG. 6 is a vertical cross-sectional view of another embodiment of the present invention.

FIG. 7 is a perspective view of a conventional reinforcing pipe.

8 is a vertical cross-sectional view taken along line IIX-IIX of FIG.

[Explanation of symbols]

 1 Reinforcement pipe 2 Pipe body 3 Reinforcement wall

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location F16S 3/00 8504-2E

Claims (1)

[Scope of utility model registration request] 1. A hollow pipe main body and a reinforcing wall integrally provided along the longitudinal direction on the inner surface side of the pipe main body, and the reinforcing wall is spiral in the longitudinal direction. Reinforcement pipe characterized by.