JP2002195474A - Vibration absorbing pipe device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration absorbing pipe device capable of having excel lent vibration absorbing properties and being durable to a repetitious high pressure. SOLUTION: The vibration absorbing pipe device is arranged between two pipes coaxially arranged, and includes a flexible means of thin metal having a bellows having a plurality of crests formed in a circumferential shape independently, respectively, and a straight pipe part integrally formed with both ends of the bellows, and a base ring formed on the outer periphery of the straight pipe part of the flexible means. The end surface of the base ring, the end surface of the bellows, and the outer peripheral surface of the straight pipe part are brazed. A reinforcing layer is formed on the brazed bellows and a base ring, and both ends of the reinforcing layer are supported on the base ring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vibration absorbing tube device. More specifically, the end face of the bellows of the expansion and contraction means arranged between two pipes arranged coaxially and the end face of the pipe, or the end face of the base ring provided on the straight pipe portion of the expansion and contraction means The present invention relates to a brazed vibration absorbing tube device.

[0002]

2. Description of the Related Art An apparatus for suppressing propagation of vibration generated from a compressor in a refrigerant circuit or an air pressure path of an air conditioner is disclosed in, for example, Japanese Patent Application Laid-Open No.
No. 318479 (Prior Art 1). This apparatus comprises straight bellows 1, 2 on both left and right sides of a bellows portion 3 composed of a plurality of peaks independently formed in a circular shape.
(See FIG. 3). The bellows portion 3 is covered with a non-extensible tube 5 braided from a material such as novoloid fiber such as Kevlar (trade name) or carbon fiber. In the case of the device of the prior art 1, when a tensile force is applied to the non-extensible tube 5, the braided structure of the tube is slightly tensile-deformed by a certain amount, but it does not elongate beyond the certain amount. I have. That is, after the non-extensible tube 5 is extended by the above-mentioned fixed amount, the tube 5
In a non-stretched state, the non-stretchable ends are fixed on the straight pipe portions 1 and 2 by caulking metal fittings.

Also, Japanese Patent Application Laid-Open No. 8-145259 discloses that, in order to suppress the propagation of vibration caused by a compressor of an air conditioner, the surface shape of a pipe is made to be corrugated, and if the pipe is made flexible, the pressure resistance is reduced. The spiral ridge 12 is formed by corrugating the inner surface of a copper, stainless steel or aluminum pipe.
A flexible reinforcing portion 13 made of polyester fiber, vinylon fiber, cotton, nylon fiber, or polyamide fiber is provided on the outer periphery of the spiral ridge 12. A device 11 is disclosed in which the end of 13 is fixed to the outer surface of a straight pipe 14 (see FIG. 4, hereinafter referred to as "prior art 2").

[0004] However, in the case of the above-mentioned prior art 1 and prior art 2, as shown in FIGS.
A step between the outer diameter of the bellows and the straight pipe section (ie,
There is a bellows height (L). On the other hand, the pipe to which the device is attached is fixed.

Therefore, as shown by the arrow X, when pressure is repeatedly applied to the bellows 3 (see FIG. 7), stress concentration occurs at the end P of the bellows 3 (see FIG. 6) due to expansion and contraction of the bellows 3. There's a problem. The stress is proportional to the pressure, and increases as the amount of axial expansion of the bellows 3 increases, and increases as the height of the peak of the bellows 3 increases.

Further, a reinforcing layer made of a stainless steel wire (SUS wire) covering the bellows portion is pressed at both ends of the bellows portion and locked by a ring, and the pressing ring is fixed to the end face of the bellows by brazing. Is also conventionally known (prior art 3).

According to the method of prior art 3, since heat is applied to the end face of the bellows at the time of brazing, there is a problem that the structure of the end face of the bellows is changed and the strength is weakened. In addition, the method of the prior art 3 can use only the SUS wire, and there is also a problem that a hole is formed in the bellows due to friction between the SUS wire and the bellows in a place where vibration is severe.

Japanese Patent Laid-Open Publication No. Hei 8-206249 discloses that FIG.
As shown in (1), a flexible tube for a sprinkler having one end connected to a water supply pipe and the other end connected to a sprinkler head mounting pipe 27 is disclosed (prior art 3).

The technical object of the present invention is to provide a flexible tube for a sprinkler which can prevent a decrease in construction efficiency of the installation of the sprinkler, unlike the prior arts 1 and 2 described above. As shown in the figure, the base ring 3 provided on the smooth portion 22 of the flexible tube main body 21
1, the end of the protective layer 29 is fixed.

In the case of the prior art 3, although the device has the advantage that the elongation of the protective layer is smaller than that of the device disclosed in the prior arts 1 and 2, which has no base ring, There is a problem that a high stress is generated by the moment in the valley of the flexible tube.

That is, in order to improve the vibration absorption of the vibration absorbing tube for suppressing the propagation of vibration generated from the compressor in the refrigerant circuit and the air pressure path, a flexible structure may be used. The bellows may have a vertical cross-sectional shape of Ω-shape in the tube, but there is a problem in that at high pressure, stress is concentrated on both end faces of the bellows, causing the bellows to break in a relatively short number of repetitions (about 100,000 times). .

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, and to provide a vibration absorbing tube device which has excellent vibration absorbing properties and can withstand repeated high pressures.

[0013]

One aspect of the present invention is a vibration absorbing tube device disposed between two coaxially arranged pipes, wherein a plurality of peaks are formed circumferentially. A thin metal expansion / contraction means provided with a bellows formed independently of each other and straight pipe parts integrally formed on both ends of the bellows, and provided on the outer periphery of the straight pipe part of the expansion / contraction means An end surface of the base ring, an end surface of the bellows and an outer peripheral surface of the straight pipe portion are brazed, and a reinforcing layer is provided on the brazed bellows and the base ring. Is characterized in that both ends are sandwiched on a base ring.

Another embodiment of the present invention relates to a vibration absorbing tube device disposed between two pipes arranged coaxially, wherein a plurality of peaks are formed circumferentially independently of each other. And a thin metal expansion / contraction means provided with a straight bellows integrally formed at both ends of the bellows, and the straight pipe portions of the expansion / contraction means are inserted into each of the two pipes. Then, the respective end faces of the two pipes, the end face of the bellows and the outer peripheral face of the straight pipe portion are brazed, and a reinforcing layer is provided on the brazed bellows and the pipe. It is characterized in that both ends are clamped on a pipe.

The end face of the bellows is substantially perpendicular to the axis of the bellows, and the thickness of the base ring is 0.5 to 1.0 times the height of the peak of the bellows. Is preferred.

The end face of the bellows is substantially perpendicular to the axis of the bellows, and the thickness of the connecting pipe is 0.5 to 1.0 times the height of the peak of the bellows. Is preferred.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration absorbing tube device (hereinafter simply referred to as "device") according to an embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

Embodiment 1 An apparatus according to this embodiment is disposed between two pipes 1 and 2 made of copper or stainless steel arranged coaxially. The apparatus includes a bellows 3, a straight pipe portion 4 integrally formed at both ends of the bellows 3, a base ring 6 provided on an outer periphery of the straight pipe portion 4, and provided on the bellows 3 and the base ring 6. (A in FIG. 1A). The reinforcing layer 5 includes a reinforcing layer 5 and a reinforcing ring 7 provided to sandwich an end of the reinforcing layer 5 between the reinforcing layer 5 and the base ring 6.
And (b)).

A plurality of peaks are formed on the bellows 3 circumferentially independently of each other. In this specification, a plurality of peaks are formed independently of each other in a circumferential shape, except that a plurality of peaks are formed in a helical shape like the bellows disclosed in the above-mentioned prior art 2. Means that The vertical section of the peak is substantially Ω-shaped.

In this embodiment, the bellows 3 and
The straight pipe portions 4 integrally formed at both ends of the bellows 3 function as expansion and contraction means.

In FIG. 1B, as shown by reference numeral B, the end face of the base ring 6, the end face of the bellows 3, and the outer peripheral face of the straight pipe portion 4 are brazed.

The reinforcing layer 5 is preferably obtained by braiding reinforcing yarns made of, for example, aramid fibers from the viewpoint of tensile strength and heat resistance. However, the material of the reinforcing layer 5 is not limited to aramid fiber. Any fiber may be used as long as it does not deteriorate even after a heat treatment at a temperature of 250 ° C. for 5 minutes.

As a material for the bellows 3, the base ring 6, and the reinforcing ring 7, for example, copper or stainless steel is suitably used.

Next, a method of manufacturing the apparatus according to the present embodiment will be described.

(Step 1) The outer diameter is 6.35 to 15.5 m
A water pressure of 15 to 30 Mpa is applied to a thin stainless steel pipe having a thickness of 0.15 to 0.2 mm and a ridge (bulge) of equal pitch is formed on the stainless steel pipe.

(Step 2) By applying a reforming process to the stainless steel pipe on which the peaks obtained in the above step are formed, a compressive force is applied in the axial direction, and the vertical cross-sectional shape of the peaks is changed to an Ω shape. At this time, if a pipe equal to the outer diameter of each peak of the bellows is passed through the straight pipe,
Both end faces of the bellows stand upright in the radial direction. In this step, the outer diameter of the bellows is about 1.4 times the outer diameter of the thin stainless steel tube.

(Step 3) Pass the base ring through the straight pipe part,
After contacting both end surfaces of the bellows, the two pipes 1 and 2 are inserted into the straight pipe. The thickness (T) of the base ring 6 is ２〜 to 1.0 of the height (L) of the peak of the bellows.
(See FIG. 1B).

(Step 4) The pipe obtained by inserting the two pipes 1 and 2 obtained in the above step 3 into a straight pipe is put into, for example, a hydrogen reduction type continuous furnace and placed at 1040 to 1050 ° C.
(B) in FIG. 1 (b) at the temperature shown in FIG. 1 (b). (Step 5) A braided reinforcing layer made of aramid fiber is braided on the bellows and the base ring to form a cylindrical reinforcing layer. Is provided.

(Step 6) Both ends of the reinforcing layer are clamped by caulking the reinforcing ring on the base ring.

Embodiment 2 An apparatus according to this embodiment includes a bellows 3 provided between two pipes 1 and 2, a straight pipe section 4 integrally formed at both ends of the bellows 3, After the straight pipe portion 4 is inserted into the two pipes 1 and 2, the bellows 3 and the two pipes 1 and 2
(A) of FIG. 2 and a reinforcing ring 7 that sandwiches both ends of the reinforcing layer 5 between two pipes 1 and 2. (B)).

As in the first embodiment, a plurality of peaks are formed on the bellows 3 circumferentially independently of each other. In this embodiment, the bellows 3 and the straight pipe portion 4 are also used.
Function as expansion / contraction means.

In FIG. 2B, as shown by reference numeral B, the respective end faces of the two pipes 1 and 2 and the end face of the bellows 3 and the outer peripheral face of the straight pipe portion are brazed. ing.

The configuration of the device of the present embodiment is the same as that of the device of the above-described first embodiment except that it does not have a base ring.

Next, a method of manufacturing the apparatus according to the present embodiment will be described.

Steps 1 and 2 are the same as those in the method of manufacturing the apparatus of the first embodiment.

(Step 3) The pipes 1 and 2 are mounted on straight pipes integrally formed on the left and right sides of a bellows having a vertical cross-sectional shape of Ω.

(Step 4) In a continuous hydrogen reduction furnace, 104
At a temperature of 0 to 1050 ° C., the two pipes 1 and 2 and the bellows are brazed.

(Step 5) A reinforcing yarn made of aramid fiber is braided on the bellows and the two pipes 1 and 2 to provide a cylindrical reinforcing layer.

(Step 6) Both ends of the cylindrical reinforcing layer are clamped by crimping a reinforcing ring on the two pipes 1 and 2.

[0040]

Next, the apparatus of the present invention will be described more specifically based on examples, but the present invention is not limited to these examples.

Example 1 A tube made of thin stainless steel having an outer diameter of 12.7 mm and a thickness of 0.15 mm, a length (bellows length) of 50 mm, a number of peaks of 20 and an outer diameter (bellows outer diameter) of 17. Bellows of 8 mm, length of straight pipe 13 mm, length 13 mm, thickness 1.
A 6 mm copper base ring is brazed to the left and right end surfaces of the bellows, a tubular reinforcing layer made of aramid fiber is applied to the bellows, and the reinforcing layer is fixed by caulking on the base ring. , And an outer diameter of 12.7
The apparatus of Example 1 was obtained by connecting pipes having a length of 0.8 mm, a thickness of 0.8 mm and a length of 50 mm to the right and left straight pipe portions of the bellows.

Comparative Example 1 A tube made of thin stainless steel with an outer diameter of 12.7 mm and a thickness of 0.15 mm, a length (bellows length) of 50 mm, 20 peaks, and an outer diameter (bellows outer diameter) of 17. 11. A cylindrical reinforcing layer made of aramid fiber is applied to the bellows having a length of 8 mm and a length of 13 mm of the straight pipe portion, and the reinforcing layer is fixed by caulking on the straight pipe portion. 7mm,
A pipe having a thickness of 0.8 mm and a length of 50 mm was connected to the right and left straight pipe portions of the bellows to obtain the device of Reference Example 1 (corresponding to the above-mentioned prior art 1).

Next, three devices each of Example 1 and Comparative Example 1 described above were prepared as samples, and a pressurization repetition test was performed.

The test conditions were as follows. Pressure: 0 to 4.15 MPa Repetition rate: 60 CPM Working fluid: Mineral oil Temperature: Normal temperature

The results of the pressure repetition test are shown in Table 1 ("times" in the table means the number of times of destruction).

[0046]

[Table 1]

The elongation of the reinforcing layer at the time of pressurization (4.15 MPa) was 0.5 mm in the device of Example 1, whereas it was 1.5 mm in the device of Comparative Example 1.

[0048]

According to the device of the present invention, a base ring or a device for attaching the device to both ends of the bellows is provided.
By brazing the pipe, the braid is less slack, so the elongation of the reinforcing layer during pressurization is reduced, and the bending stress generated at both ends of the bellows is also reduced.
The durability is greatly improved even at high pressures.

[Brief description of the drawings]

FIG. 1 is a partially sectional explanatory view and an enlarged view of a main part showing an example of an apparatus according to an embodiment of the present invention.

FIG. 2 is a partially sectional explanatory view and an enlarged view of a main part showing an example of an apparatus according to another embodiment of the present invention.

FIG. 3 is a partially broken explanatory view showing an example of a conventional vibration absorbing tube device.

FIG. 4 is a partially cutaway explanatory view showing another example of a conventional vibration absorbing tube device.

FIG. 5 is an illustration showing the structure of a conventional flexible tube.

FIG. 6 is an explanatory sectional view showing functions of the device of FIG. 3;

FIG. 7 is an explanatory sectional view showing functions of the device of FIG. 3;

[Explanation of symbols]

 1, 2 pipe 3 bellows 4 straight pipe part 5 reinforcing layer 6 base ring 7 reinforcing ring B row

Claims (4)

[Claims] 1. A vibration-absorbing tube device disposed between two pipes arranged coaxially, wherein a bellows having a plurality of peaks formed independently from each other in a circumferential shape.
The bellows comprises a thin metal expanding / contracting means provided with a straight pipe portion integrally formed at both ends of the bellows, and a base ring provided on the outer periphery of the straight pipe portion of the expanding / contracting means. The end surface, the end surface of the bellows and the outer peripheral surface of the straight pipe portion are brazed, and a reinforcing layer is provided on the brazed bellows and the base ring, and both ends of the reinforcing layer are formed on the base ring by the reinforcing ring. A vibration absorbing tube device which is sandwiched. 2. A vibration-absorbing tube device disposed between two pipes arranged coaxially, wherein a bellows having a plurality of peaks each formed circumferentially independently of each other;
A straight pipe portion integrally formed at both ends of the bellows; and a thin metal expansion / contraction means. The straight pipe portion of the expansion / contraction means is inserted into each of two pipes.
The end face of each of the pipes, the end face of the bellows and the outer peripheral face of the straight pipe portion are brazed, and a reinforcing layer is provided on the brazed bellows and the pipe, and both ends of the reinforcing layer are formed on the pipe. A vibration absorbing tube device which is sandwiched by a reinforcing ring. 3. An end face of the bellows is substantially perpendicular to an axis of the bellows, and a thickness of the base ring is 0.5 to 1.0 times a peak height of the bellows. Item 4. The vibration absorbing tube device according to Item 1. 4. An end face of the bellows is substantially perpendicular to an axis of the bellows, and a thickness of the connecting pipe is 0.5 to 1.0 times a height of a peak of the bellows. The vibration absorbing tube device according to claim 2.