JP2007278433A - Flexible tube - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible tube preventing an elastic material in an intermediate layer from being extruded outside from the mesh of a reinforcing layer without increasing metal used for the reinforcing wire of the reinforcing layer. <P>SOLUTION: The reinforcing layer 3 is formed by braiding a first reinforcing wire 3a formed of metal, and a second reinforcing wire 3b formed of organic fiber. Consequently, the first reinforcing wire 3a formed of metal is not increased even when the reinforcing layer 3 is braided in high density with no clearance. The effect of wear prevention and pressure-proof reinforcement by the intermediate layer 2 can thereby be positively maintained without causing defects such as the degradation of flexibility, an increase of weight, the degradation of vibration absorbing property and diameter enlargement in comparison with the case of braiding the reinforcing layer 3 in high density only with the reinforcing wire of metal or forming the reinforcing layer of metal in two layers. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a flexible tube used for high-pressure piping such as refrigerant piping of a vehicle air conditioner and hydrogen piping of a fuel cell vehicle.

  In general, a flexible tube formed of a bellows-like metal tube has flexibility and pressure resistance, and is impermeable to various fluids compared to non-metallic flexible tubes such as rubber. It is used for various pipes such as water supply pipes and gas pipes.

In addition, as a high-pressure flexible tube such as one used for a carbon dioxide refrigerant pipe of a vehicle air conditioner, a tube body made of a bellows-like metal tube, an intermediate layer covering the outer peripheral surface of the tube body, and an intermediate And a reinforcing layer that covers the outer peripheral surface of the layer. The reinforcing layer provides pressure-proof reinforcement of the tube body, and an intermediate layer between the tube body and the reinforcing layer causes wear and damage due to contact between the tube body and the reinforcing layer. What prevents (perforation) is known (for example, refer to FIG. 3 of Patent Document 1).
Japanese Patent Laid-Open No. 9-14528

  By the way, as the material used for the intermediate layer, an elastic material such as rubber is suitable in terms of flexibility and vibration absorption, but the reinforcing layer is formed by braiding a reinforcing wire made of metal. Therefore, when the reinforcing layer is reduced in diameter along with the expansion of the bellows-like metal tube under high pressure and the intermediate layer is compressed, the elastic material of the intermediate layer is pushed out from the stitches of the reinforcing layer, pressure resistance reinforcement and wear prevention There was a problem of lowering the effect. Even if the original design strength is sufficient, the above-mentioned problems can be solved by braiding the reinforcing wire of the reinforcing layer at a high density or by using two reinforcing layers as a countermeasure. However, in this case, since the number of reinforcing wires made of metal increases, problems such as a decrease in flexibility, an increase in weight, a decrease in vibration absorption, an increase in diameter, etc. occur and the value of the product is reduced. There is a problem.

  The present invention has been made in view of the above problems, and the object of the present invention is to push the elastic material of the intermediate layer from the stitches of the reinforcing layer to the outside without increasing the metal used for the reinforcing wire of the reinforcing layer. It is to provide a flexible tube that is not damaged.

  In order to achieve the above object, the present invention comprises a tube body made of a bellows-like metal tube, an intermediate layer covering the outer peripheral surface of the tube main body, and a reinforcing layer covering the outer peripheral surface of the intermediate layer, In the flexible tube formed of elastic material, the reinforcing layer is formed by braiding a first reinforcing wire made of metal and a second reinforcing wire made of organic fiber.

  As a result, the reinforcing layer is formed by braiding the first reinforcing wire made of metal and the second reinforcing wire made of organic fiber, so that the reinforcing layer is braided with high density without a gap. However, the first reinforcing wire made of metal is not increased.

  According to the flexible tube of the present invention, even when the reinforcing layer is braided with a high density without a gap, the metal used for the reinforcing wire of the reinforcing layer is not increased. Compared to braiding the density or using two metal reinforcing layers, there is an advantage of not causing problems such as a decrease in flexibility, an increase in weight, a decrease in vibration absorption, and an increase in diameter. is there. Therefore, by braiding the reinforcing layer with a high density without a gap, even when the intermediate layer is compressed by expansion of the tube body under high pressure, the elastic member of the intermediate layer can be pushed out from the stitches of the reinforcing layer. Therefore, the effect of pressure-proof reinforcement and wear prevention by the intermediate layer can be reliably maintained.

  1 and 2 show an embodiment of the present invention. FIG. 1 is a partial perspective view of a flexible tube, and FIG. 2 is a partial sectional side view thereof.

  The flexible tube includes a tube main body 1 made of a flexible metal tube, an intermediate layer 2 that covers the outer peripheral surface of the tube main body 1, and a reinforcing layer 3 that covers the outer peripheral surface of the intermediate layer 2. .

  The tube body 1 is made of, for example, a thin-walled tube made of stainless steel, and is formed in a bellows shape so as to have flexibility. That is, the peripheral surface of the tube body 1 is bent in a waveform so that the large diameter portions 1a and the small diameter portions 1b are alternately arranged in the tube axis direction.

  The intermediate layer 2 is made of an elastic material such as rubber or silicone, and is filled in the outer peripheral surface of the tube main body 1 without a gap. That is, the intermediate layer 2 fills the concave portions between the large diameter portions 1a of the tube main body 1, and covers the tube main body 1 so that the outer diameter is larger than each large diameter portion 1a.

  The reinforcing layer 3 is formed by braiding a first reinforcing wire 3a made of a metal such as a stainless wire and a second reinforcing wire 3b made of an organic fiber such as an aramid fiber by blade knitting. In this case, the first reinforcing wire 3a and the second reinforcing wire 3b are braided with each other plurally, and are braided with high density so that no gap is formed between the reinforcing wire 3a and 3b. That is, the second reinforcing wire 3b made of organic fiber is lighter and more flexible than the first reinforcing wire 3a made of metal.

  In the flexible tube configured as described above, the first and second reinforcing wires 3a and 3b of the reinforcing layer 3 are braided with a high density so as not to form a gap. Even when the reinforcing layer 3 is reduced in diameter and the intermediate layer 2 is compressed in accordance with the elongation of the tube body 1 made of a metal tube, the elastic material of the intermediate layer 2 is not pushed out from the stitches of the reinforcing layer 3. At this time, since the second reinforcing wire 3b is formed of organic fibers, the reinforcing layer 3 can be braided with high density without increasing the first reinforcing wire 3a made of metal.

  As described above, according to the flexible tube of the present embodiment, the reinforcing layer 3 is formed by braiding the first reinforcing wire 3a made of metal and the second reinforcing wire 3b made of organic fiber. Even when the layer 3 is braided with high density without a gap, the first reinforcing wire 3a made of metal is not increased. Therefore, compared with the case where the reinforcing layer 3 is braided with a metal reinforcing wire only at a high density, or the metal reinforcing layer is made of two layers, the flexibility is decreased, the weight is increased, the vibration absorption is decreased, It is possible to reliably maintain the effects of pressure-proof reinforcement and wear prevention by the intermediate layer 2 without causing problems such as diameters.

  In addition, since a plurality of the first reinforcing wire 3a and the second reinforcing wire 3b are braided, the braid can be braided as in the case of only the metal reinforcing wire, and the production can be efficiently performed.

  3 and 4 show another embodiment of the present invention. FIG. 3 is a partial perspective view of the flexible tube, and FIG. 4 is a partial sectional side view thereof. In addition, the same code | symbol is attached | subjected and shown to the component equivalent to the said embodiment.

  The flexible tube of this embodiment includes a cover layer 4 that covers the outer peripheral surface of the reinforcing layer 3. The cover layer 4 is made of an elastic material such as rubber and is formed in a tubular shape so as to cover the outer peripheral surface of the reinforcing layer 3. Thereby, since the reinforcement layer 3 can be protected by the cover layer 4, durability can be improved.

  In each of the above embodiments, a plurality of the first reinforcing wire 3a and the second reinforcing wire 3b are braided. However, for example, the first reinforcing wire 3a and the second reinforcing wire 3b You may make it braid what arrange | positioned alternately one by one.

The fragmentary perspective view of the flexible tube which shows one Embodiment of this invention Partial cross-sectional side view of flexible tube The fragmentary perspective view of the flexible tube which shows other embodiment of this invention. Partial cross-sectional side view of flexible tube

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Tube main body, 2 ... Intermediate | middle layer, 3 ... Reinforcement layer, 3a ... 1st reinforcement wire, 3b ... 2nd reinforcement wire, 4 ... Cover layer.

Claims (3)

In a flexible tube comprising a tube main body made of a bellows-like metal tube, an intermediate layer covering the outer peripheral surface of the tube main body, and a reinforcing layer covering the outer peripheral surface of the intermediate layer, the intermediate layer formed of an elastic material,
The flexible tube, wherein the reinforcing layer is formed by braiding a first reinforcing wire made of metal and a second reinforcing wire made of organic fiber. The flexible tube according to claim 1, wherein a plurality of the first reinforcing wires and the second reinforcing wires are braided. The flexible tube according to claim 1, further comprising a cover layer that covers an outer peripheral surface of the reinforcing layer.

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