JP3242805B2 - Telescopic metal bellows tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescopic metal bellows tube having a built-in spiral metal reinforcement, which is suitably used for air-conditioning, air-conditioning, air-conditioning, and odor removal of buildings such as houses and buildings.

[0002]

2. Description of the Related Art A conventional telescopic bellows tube of this type is disclosed in Japanese Patent Publication No. 51-48553.
The metal strips are bonded to each other with a solvent-type adhesive or a hot-melt type adhesive. The same publication also discloses an idea of manufacturing a stretchable metal bellows tube by welding metal strips by ultrasonic waves without using an adhesive, but has specifically reached practical use. I didn't.

[0003]

As described above, when the metal strips are bonded (joined) with a solvent type adhesive or a hot melt type adhesive, any of the adhesives is made of an organic substance. Therefore, it was not functionally made of a completely non-combustible material as a telescopic metal bellows tube, so that it could not be used for high-temperature applications or applications requiring complete noncombustibility. Furthermore, in the bonding (joining) method using an adhesive, it is not possible to prevent variations in adhesive strength due to uneven concentration and application of the adhesive. And the adhesive applied at the time of manufacture adhered to the tube forming apparatus and the rollers in the previous process, and there was a problem that the metal strip could not be stably fed into the tube forming apparatus. Therefore, a method of manufacturing a telescopic metal bellows tube by welding metal strips together by ultrasonic waves without using an adhesive has been filed as Japanese Patent Application No. 6-193676. However, it has been found that simply joining the metal strips together by ultrasonic welding at the portion to be bonded (joined) with the conventional adhesive reduces the elasticity and flexibility, which are important functions of the elastic metal bellows tube. Was. This is the same as the bonding (bonding) part using the conventional adhesive is a flexible bonding, and the bonding part by ultrasonic welding is the same as thickening the metal foil of the metal strip. It was considered that the difference was due to the difference in the stress with respect to. The present invention has been made in view of the above-described problems ,
It is an object of the present invention to provide a novel telescopic metal bellows tube having a heat-resistant and nonflammable structure capable of stably and continuously producing and having excellent elasticity and flexibility.

[0004]

According to the present invention, in order to solve the above-mentioned problems, a telescopic metal bellows tube has the following structure.

[0005] The stretchable metal bellows tube 1 of the present invention is formed by winding a metal band 5 having a metal reinforcement 52 attached thereon, which is easily formed on the adjacent metal band 5 in a spiral shape. The metal reinforcing body is knitted so that the position of the metal reinforcement is substantially at the peak 3, and is a shoulder between the peaks, and the pipe wall of the overlapping portion 6 excluding the valley bottom 41 is formed. Knurled eyes
To be joined by ultrasonic welding, also single valley bottom of the metal strip
It is a telescopic metal bellows tube having a two-layer or two-layer structure .

The above-described joint 7 by ultrasonic welding can be located at any position except for the valley bottom 41, but it is particularly preferable that the joint 7 is located at the shoulder 31.

Furthermore, ultrasonic welding joints 7 and this is particularly knurled shape than flat shape is preferred.

[0008]

The expansion / contraction metal bellows tube of the present invention will be described below while explaining the movement of the wall when the expansion / contraction metal tube is expanded and contracted. The telescopic metal bellows tube has a portion where the metal reinforcing member of the metal band is located, that is, a peak 3 of the bellows tube as a fulcrum and a valley 4.
Displacement allows extension and contraction.
When the elastic metal bellows tube is bent, the outside of the bent portion is in an extended state, and the inside is in a contracted state. In these cases, the valley bottom 41 has the largest pipe diameter displacement. In addition, in the conventional elastic metal bellows tube, since the metal strip which is easy to shape is joined by bonding, the tube wall is flexible even at the joint. However, when metal strips that are easy to shape are joined by ultrasonic welding, the metal foils 51 that are substantially overlapped are integrated and thickened, so that rigidity is increased and a flexible tube wall is not formed.

In the above-structured telescopic metal bellows tube of the present invention, an overlapped portion of a metal band easy to shape except for at least a valley bottom is ultrasonically welded. Therefore, even when the telescopic metal bellows tube is expanded or contracted, the valley bottom 41 having the largest amount of tube diameter displacement is not welded by ultrasonic welding, so that it can be easily expanded or contracted or bent.

[0010] If only the shoulder 31 which is the tube wall having the least amount of tube diameter displacement during expansion and contraction is ultrasonically welded and joined, it is possible to expand and contract more easily. Also,
In addition, the ultrasonic welding joint end 71, which is most likely to be a bending point when a force is applied, is located away from the valley bottom, so that stress on the pipe wall at the time of bending is dispersed near the valley bottom 41, and bending durability is improved. improves.

Further, the ultrasonic welding joint 7 is provided with a
The cross-shaped shape not only allows the metal band to be firmly joined by the anchoring action of the knurled eyes, but also allows the knurled eyes to act as a bending point as compared to simply ultrasonically welding in a flat shape. (Tube hypotenuse), and the expansion and contraction and bending properties are improved. The shapes shown in FIGS. 2A to 2F can be considered as the knurls, but are not particularly limited.

Next, the metal band forming the tube wall will be described. The configuration of the metal strip can be roughly classified into two types, but is not particularly limited in the present invention.

One is a type in which a metal reinforcing member 52 is placed on a tape of a metal foil 51 shown in FIG. In the case of forming a telescopic metal bellows tube using this type of metal band 5, as shown in FIGS. 4B to 6, one pitch of the bellows tube is overlapped, or as shown in FIG. The metal strips 5 are sequentially superimposed and wound while overlapping only the portion from the shoulder 31 to the peak 3 to form a tube wall. The telescopic metal bellows tube in this case has a valley 4
Is a two-layer or single-layer metal foil. However, the metal strip described above is a single-layer metal foil tape on which a metal reinforcement is placed. However, if a metal strip is placed on a tape in which two layers of metal foil are stacked, a metal strip is used. The valley of the telescopic metal bellows tube having the configuration shown in FIG. 7 is also a two-layer metal foil.

Another type of metal strip is shown in FIG.
This is a type in which a metal reinforcing member is incorporated in the folded portion of the metal foil tape shown in (a). When a telescopic metal bellows tube is formed using this type of metal band, the metal band is sequentially overlapped while overlapping only the portion from the shoulder to the peak of the bellows tube as shown in FIG. The tube wall is formed by overlapping and winding. As shown in FIG. 3C, when the metal foil tape is folded in half at the center in the width direction, the metal foil at the valley of the bellows tube becomes two layers, but the portion near the end of the metal foil tape By folding the metal foil into two so as to incorporate the metal reinforcing member, the metal foil at the valley of the bellows tube can be made into a single layer.

It is possible to make the metal foil at the valley portion of the bellows tube into a single layer or two layers by using any of the above two metal strips. It is preferable that the metal foil in the valley is a single layer in order to improve the value. However, a metal foil having a single-valley valley is lightweight, but when bending is repeated, holes are easily generated and fractured from the bottom of the valley due to metal fatigue. An elastic metal bellows tube having two layers of valleys has high bending resistance but is heavy. Therefore, these detailed configurations can be appropriately selected according to various conditions.

The metal reinforcing member located at the top of the mountain holds the shape of the tube and acts as a fulcrum during expansion and contraction. The material is not particularly limited as long as it is rigid, but if it is a carbon steel wire, it has a high rigidity and retains the tubular shape even if the steel wire diameter is small, and it becomes a fulcrum at the time of expansion and contraction. preferable. The metal foil forming the tube wall is not particularly limited as long as it can be easily shaped. Aluminum foil, copper, iron, lead, etc., and their alloys are examples of metal foils that can be easily shaped. Further, a metal foil laminated or coated with a resin such as PET (polyethylene terephthalate) can also be used.
It is not preferable because it deviates from the object of the present invention.

The pipe of the present invention is shown in FIG.
Metal strip 5 having a metal reinforcement as shown in (a)
For example, as shown in JP-B-51-48453, a plurality of rollers rotating in the same direction and having equally spaced reinforcing member guide grooves on the respective peripheral surfaces are gathered together to form a tube for forming one tube. While rotating and advancing helically along the tube forming peripheral surface of the roller group arranged to constitute a surface, the adjacent metal strips are sequentially overlapped with each other, and at least one roller of the roller group is At least one flat peripheral portion between the reinforcing member guide grooves is provided, and a horizontal vibration type rotary horn of the ultrasonic welding machine is made to correspond to the flat peripheral portion of the roller, and the flat peripheral portion of the rotary horn and the roller is provided. It is manufactured by pressing a metal strip between them and continuously seam bonding.

The bellows tube thus constructed is made of only a material of a rigid metal reinforcing member such as a carbon steel wire and a material of an easily shapeable metal band such as an aluminum foil, a copper foil and an iron foil. As a result, it becomes a telescopic metal bellows tube having excellent heat resistance and non-combustibility and excellent flexibility and elasticity.

[0019]

EXAMPLES A telescopic metal bellows tube as an example product and a comparative example product of the present invention was manufactured as follows.

Example 1 As shown in FIG. 3A, an aluminum foil tape having a thickness of 40 μm, which is easy to shape, was folded in two, and a diameter of 1.times.
As shown in FIG. 3 (b), a metal strip having a built-in 2 mm carbon steel wire as a metal reinforcing member is sequentially spirally overlapped and spirally wound over the bellows tube from the shoulder to the peak. 3m wide with knurls shown in (b)
While pressing the rotary horn of m, the metal band at the top of the bellows tube is continuously welded by ultrasonic waves, and the position of the metal reinforcement is set to the top by the roller, so that almost the center becomes the valley. Had a habit. As ultrasonic welding conditions,
Using 40kHz ultrasonic oscillator, lateral vibration amplitude 25μm
And pressurizing 2.5 kgf, the outer diameter of the pipe is 130 m
A telescopic metal bellows tube having a length of m and a pitch of 16 mm was obtained.

Example 2 As shown in FIG. 4 (a), a metal strip using a 1.2 mm diameter carbon steel wire as a metal reinforcing member on a 40 μm-thick aluminum foil tape which is easy to shape is shown. As shown in FIG. 6, one pitch of the bellows tube is sequentially overlapped and wound spirally while overlapping, and a 3 mm-wide rotary horn with knurls shown in FIG. Weld the metal strip on the mountain shoulder continuously by ultrasonic waves,
The position of the metal reinforcing member was set to a peak by a roller, and the metal reinforcing member was formed so that the center thereof became a valley. Ultrasonic welding was performed using a 40 kHz ultrasonic oscillator under the conditions of a lateral vibration amplitude of 25 μm and a pressing force of 2.5 kgf, to obtain a telescopic metal bellows tube having a tube outer diameter of 130 mm and a pitch of 16 mm.

Comparative Example 1 As shown in FIG. 3 (a), an aluminum foil tape having a thickness of 40 μm, which is easy to shape, was folded in two, and a diameter of 1.
As shown in FIG. 8 (a), a metal strip having a built-in 2 mm carbon steel wire as a metal reinforcement is successively overlapped and spirally wound around the valley to the top of the bellows tube with an adhesive. The metal strips at No. 7 were continuously bonded. Rolling is performed so that the center between metal reinforcements becomes a valley with a roller, pipe outer diameter 130 mm, pitch 16 m
m telescopic metal bellows tube was obtained.

Comparative Example 2 As shown in FIG. 3A, an aluminum foil tape having a thickness of 40 μm, which is easy to shape, was folded in two, and a diameter of 1.0 mm was applied to the folded part.
As shown in FIG. 8 (a), a metal strip having a built-in 2 mm carbon steel wire as a metal reinforcing member is sequentially overlapped and spirally wound while overlapping from the valley to the peak of the bellows tube. The metal band at the valley of the bellows tube was continuously welded by ultrasonic waves while pressing the rotary horn having a flat surface, and the roller was knitted so that the valley was formed almost at the center between the metal reinforcements. As a welding condition using ultrasonic waves, a 40 kHz ultrasonic oscillator was used under conditions of a lateral vibration amplitude of 25 μm and a pressing force of 2.5 kgf to obtain a telescopic metal bellows tube having a tube outer diameter of 130 mm and a pitch of 16 mm.

The telescopic metal bellows of Example 1 and Example 2 and Comparative Example 2 are made of a metal material only, and therefore have heat resistance and noncombustibility. However, when the comparative example product 2 was extended and contracted, both the extension and the contraction were hard and the flexibility was not sufficient. At this time, when the cross section at the time of contraction was observed, it could not be completely contracted as shown in FIG. The product of Comparative Example 1 had sufficient stretchability and flexibility, but was inferior in heat resistance and incombustibility due to the use of an adhesive. On the other hand, the product 1 and the product 2 of the present invention were heat-resistant and non-flammable, and they were elastic metal bellows tubes having excellent flexibility and elasticity due to the structure while having heat resistance and nonflammability.

When the product is continuously manufactured for a long time, the comparative product 1
In this method, the adhesive applied at the time of manufacturing adhered to the tube forming apparatus and the rollers in the previous process, and a problem occurred that the metal strip could not be stably fed into the tube forming apparatus. Moreover, since ultrasonic welding was performed on the comparative example product 2 using a flat rotary horn, the ultrasonic welding of the metal band was not stable. On the other hand, Example product 1 and Example product 2 could be stably produced without any problem, and the strength of the welded joint was sufficient.

[0026]

Since the present invention is configured as described above, it has the following effects. Telescopic metal bellows tube of the present invention, while having heat resistance and incombustibility, position the joint portion excluding the root portion by ultrasonic welding, excellent stretchability and so were particularly positioned Yamakata section flexible Having. In addition, the structure enables stable and continuous production. Particularly, since the ultrasonic welding joint has a knurled shape, the joining strength is sufficient, and further stable and continuous production is possible.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a telescopic metal bellows tube of the present invention.

FIG. 2 is a perspective view of a knurled eye according to the present invention.

FIG. 3 is a sectional view showing in detail a metal band and a tube wall of the telescopic metal bellows tube of the present invention.

FIG. 4 is a sectional view showing in detail a metal band and a tube wall of another telescopic metal bellows tube of the present invention.

FIG. 5 is a cross-sectional view showing in detail a tube wall of yet another telescopic metal bellows tube of the present invention.

FIG. 6 is a sectional view showing in detail a tube wall of still another telescopic metal bellows tube of the present invention.

FIG. 7 is a cross-sectional view showing in detail a tube wall of still another elastic metal bellows tube of the present invention.

FIG. 8 is a sectional view showing a tube wall of a comparative example in detail.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 telescopic metal bellows tube 3 mountain top 31 mountain shoulder 4 valley 41 valley bottom 5 metal band 51 metal foil 52 metal reinforcement 6 metal band superimposed part 7 ultrasonic welding part 71 ultrasonic welding part edge

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yukio Kuno 1034, Oda, Wada, Sasaguri-machi, Kasuya-gun, Fukuoka Examiner at Kyoritsu Airtech Co., Ltd. Examiner Manji Mizutani (56) References JP 50-26749 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16L 11/16 B21C 37/12

Claims (1)

(57) [Claims] An easy-to-form metal strip having a metal reinforcement attached thereto is spirally superposed and wound on the adjacent metal strip sequentially to form a tube wall, and the position of the metal reinforcement is determined. It is habited to be almost the top of a mountain, and the pipe wall is a shoulder between the tops of the peaks and at the overlapped portion except for the bottom of the valley.
Ultrasonic welding welding in the form of knurls, and the bottom of the valley is
An elastic metal bellows tube having a single-layer or two-layer structure of a metal band .