JP2603591B2 - Thin metal flexible tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally requires bending at the time of piping to a mating member such as an engine and a radiator such as a radiator hose of an automobile or the like, and under a condition of high temperature and high pressure where a large vibration is applied. The present invention relates to a thin-walled metal flexible tube used in the above-mentioned and required to have high durability reliability.

[0002]

2. Description of the Related Art Conventionally, technologies in such a field include, for example, as shown in FIG.
Because of the large vibration generated by the engine 11, the flexible tube 13 made of rubber having a large flexibility or a thin-walled metal tube having a substantially full-length corrugated pipe is provided.
Is used.

[0003]

However, the rubber flexible tube having the above-mentioned structure has a large wall thickness due to the required heat resistance, pressure resistance and the like.
In addition, bending vulcanization molding using a bent core metal is necessary in use, resulting in poor productivity and high price. Further, heat resistance and weather resistance are deteriorated due to the properties of rubber, and deterioration occurs due to vibration over a long period of time. There was a problem in durability such as generation of cracks.

In addition, a thin metal flexible tube having a substantially full length of a waveform requires a long tube length so as to increase the area of the tube wall, so that the weight is increased and the natural frequency is too low, so that the overall amplitude is large. Since there is a danger that the tube will run out, interfere with other parts and cause wear, cracks, cracks, and the like on the tube, a clamp for fixing may be required in some cases.

Accordingly, an object of the present invention is to provide a flexible tube which has solved the problems of the conventional flexible tube such as productivity and durability reliability.

[0006]

In order to achieve the above object, the present invention provides a flexible tube made of a thin metal, for example, stainless steel, and a first embodiment has a low mountain corrugated tube at a portion to be bent by plastic deformation. Part, and a straight part is provided integrally with a corrugated pipe part having a U-shaped or Ω-shaped cross section of a high peak which can be elastically deformed by interposing a straight pipe part between the corrugated pipe part and the low peak corrugated pipe part. The gist of the present invention is that the displacement is absorbed by the high mountain corrugated tube. The second embodiment has a straight tube between the low mountain corrugated tube and the low mountain corrugated tube. A straight section integrally formed with a U-shaped or Ω-shaped corrugated pipe section of a high peak which can be elastically deformed by interposition, and a plastic section for piping between the low peak corrugated pipe section and a mating member. Bending by deformation, the displacement is absorbed by the high mountain corrugated pipe. The gist of the present invention is that it is configured to

[0007]

[Function] Since a thin-walled metal pipe is provided at a portion where a thin-walled metal pipe is bent in this manner, it is plastically deformed with a smaller force than a thin-walled metal pipe that is not corrugated and easily buckled. In addition to being able to bend easily with a small bending radius as desired, piping can be easily performed, and this plastic deformation increases the rigidity of the bent portion, maintains the bent shape, and transmits vibration applied from the outside to the straight portion, Since the straight section not subjected to bending is provided with a straight pipe section and a high-profile U-shaped or Ω-shaped corrugated pipe section generally called “Omega”, conduction was conducted from outside through the bent section and the straight pipe section. In addition to vibration, this tube can effectively absorb the displacement such as thermal strain received by the tube and the strain generated at the time of installation by elastic deformation, and the interposed straight pipe reduces the material used and reduces the weight. And also as a whole It is intended to prevent the occurrence of deflection of large amplitude to prevent lowering of frequency.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a thin metal flexible tube of the present invention, and FIG. 2 shows a case where the flexible tube of the present invention is installed as a radiator hose in an automobile. 3 is an enlarged sectional view taken along line III-III in FIG. 1, and FIGS. 4 and 5 are enlarged sectional views taken along line IV-IV in FIG. 1, showing two embodiments. FIG. In the drawing, (1) is an engine, (2) is a radiator,
(3) is a thin metal flexible tube of the present invention. In the illustrated embodiment, the tube (3) is made of, for example, SUS 304, an outer diameter of 40 m / m, and a wall thickness of 0.3 m / m.
m, and a part subjected to bending by plastic deformation has a peak diameter of 45 m / m and a valley diameter of 40 m / m.
m, U-shaped cross section like pitch 9m / m (see Fig. 3)
Of the engine (1) side and the radiator (2) side as mating members with the low wavy pipe part (3a) of the mountain for bending.
It is provided in two places. In addition, straight pipes (3c, 3c) are provided on both sides in the substantially central portion of the straight portion where the bending process is not performed between the low mountain corrugated pipes (3a, 3a) for performing bending by plastic deformation at the two places. The peak diameter 52m /
m, a valley diameter of 40 m / m, and a pitch of 6 m / m in cross section Ω shape (see FIG. 4). A high peak corrugated pipe portion (3b) is provided and integrated with the low peak corrugated pipe portions (3a, 3a). And the high mountain-like corrugated tube (3b) absorbs external displacement. (4) O-ring storage spool, (5) O-ring for sealing,
(6) is a U-band for retaining, (7) is a pull-out preventing claw,
(8) shows an annular concave groove provided on the connecting branch pipe of the radiator (2) for locking the pull-out preventing claw (7).

In this way, the low mountain corrugated tube (3)
a) can be manually bent and plastically deformed so that the bending radius associated with the pipe between the engine (1) and the radiator (2) is 40 m / m at the center of the pipe, and fixing by a clamp or the like is unnecessary. It is not necessary to use a power bender or the like used for bending a tube that is not subjected to such waveform forming, and the bending can be performed in a short time by using an inexpensive hand bending jig. In addition, since the bending by plastic deformation is performed, the rigidity is increased compared to before bending, and the bent shape is maintained.
The deformation associated with the vibration at the point is reduced, and the generated stress is also reduced. On the other hand, the wavy tube portion (3b) provided with a high peak at the substantially central portion of the straight portion and having a very flexible and elastically deformable Ω-shaped cross section is a low-peak wavy tube portion (3).
a) and not only the vibrations transmitted from the straight pipe portions (3c, 3c), but also the flexible tube (3) intensively absorbs the displacement such as the thermal strain and the strain at the time of mounting by elastic deformation, and the high peak The stress generated due to the effect of dispersion of the stress caused by the height and the cross-sectional Ω shape can be reduced, sufficient displacement absorption and high durability reliability can be obtained, and approximately evenly on both sides of the corrugated pipe portion (3b) having a high mountain. The provided straight pipe portion (3c) prevents the natural frequency from lowering, and prevents the occurrence of large amplitude swing as a whole, thereby preventing interference with other components. FIG. 5 shows another embodiment of the present invention, in which a corrugated tube portion (3b) of a high mountain which can be elastically deformed is formed in a U-shaped cross section, and is equivalent to the Ω-shaped cross section in FIG. The effect of is obtained.

When comparing the thin metal flexible tube of the present invention with a conventional general rubber flexible tube, the rubber flexible tube has an outer diameter of 48 m / m, a wall thickness of 4 m / m, and a developed length of about 360 m / m. m had a weight of about 250 gr, but the above embodiment of the present invention had a weight reduction of about 190 gr, about 25%, and had cracks due to poor heat resistance and weather resistance, which are disadvantages of rubber. There is no occurrence, and it is also possible to eliminate the need for large heat energy consumption and a long processing time in the bending and forming of the rubber flexible tube (the cloth is wound around the bent core bar and vulcanized).

[0011]

As described above in detail, according to the present invention, while having flexibility equal to or higher than that of a rubber flexible tube, the amplitude of the run-out is small, and the heat resistance of the rubber flexible tube is reduced.
Embrittlement due to low weather resistance and the accompanying cracks and leakage can be prevented, heat resistance and durability reliability are improved, and rubber fabric and cord as necessary A so-called rubber hose, which is wound together with a coil, pressurized in a mold, held at a high temperature for a long time, vulcanized, cooled and removed from the cored bar (a secondary vulcanization step is also required depending on the type of rubber). This eliminates the need for any bending process, so that not only the number of processes is greatly reduced, but also the processing time and energy are saved and the production can be performed at low cost.

Further, according to the present invention, compared with a flexible tube in which a thin metal tube is corrugated substantially over its entire length, the use of less material can be achieved due to the provision of the straight tube portion, and the weight can be reduced.
In addition, it is possible to prevent the occurrence of large vibrations due to a decrease in the natural frequency and to prevent interference with other components without the need for a clamp or the like.

Further, according to the present invention, since a low mountain corrugated pipe portion is provided at a portion where bending by plastic deformation is performed, a bending radius with a small bending radius and a very small bending as required in bending by plastic deformation is provided. It can also be implemented by force and with a simple hand bending jig.

[Brief description of the drawings]

FIG. 1 is a front view of a thin metal flexible tube of the present invention.

FIG. 2 is a partially cutaway sectional view of a radiator hose installed in an automobile.

FIG. 3 is an enlarged sectional view taken along line III-III of FIG.

FIG. 4 is an enlarged sectional view taken along line IV-IV of FIG. 1;

FIG. 5 is a diagram corresponding to FIG. 4 in another embodiment.

FIG. 6 is a side view showing a conventional rubber flexible tube.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engine 2 Radiator 3 Thin metal flexible tube 3a Low mountain corrugated tube 3b High mountain corrugated tube 3c Straight tube

Claims (2)

(57) [Claims] 1. A low-peak corrugated pipe portion is applied to a portion to be bent by plastic deformation, and a straight pipe portion is interposed between a straight portion and the low-peak corrugated tube portion to elastically deform. A thin metal flexible tube characterized in that a corrugated tube having a U-shaped or Ω-shaped cross section of a high peak is integrally provided, and the displacement is absorbed by the corrugated tube of the high peak. 2. A high-peak U-shaped or Ω-shaped corrugated pipe section which is elastically deformable by interposing a straight pipe section between the low-peak wave section and the low-peak wave section. The low peak corrugated pipe portion is subjected to bending by plastic deformation for piping between the mating member and the high peak corrugated pipe portion to absorb displacement. A thin metal flexible tube characterized by the following.