JP2005036968A - Pressure resistant vibration absorption hose having excellent resistance to gas permeability - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure resistant vibration absorption hose having excellent resistance against gas permeability in addition to withstand pressure performance and vibration absorption property and capable of shortening hose length. <P>SOLUTION: Reinforcing yarns are knitted on an outer face of a cylindrical inner side rubber layer 16 having a bellows part to laminate a reinforced layer 18. When depth of knitting of a trough part 18-1 in the bellows part in the reinforced layer 18 is b and depth of a trough part 16-1 in the bellows part in the inner side rubber layer 16 is a, the reinforcing yarns in the reinforced layer 18 are knitted to satisfy 0≤b≤0.7a. An opening angle θ of the trough part 16-1 in the bellows part in the inner side rubber layer 16 is set θ≤100°. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pressure-resistant vibration absorbing hose having excellent gas permeation resistance, and particularly relates to a pressure-resistant vibration absorbing hose suitable for being applied to a piping hose disposed in an engine room of an automobile.

Conventionally, hoses mainly composed of a cylindrical rubber layer have been widely used in various applications as industrial and automotive hoses.
The main purpose of using such a hose is to absorb vibrations.

  For example, in the case of a piping hose disposed in an engine room of an automobile, the engine vibration, the compressor vibration of an air conditioner (in the case of a refrigerant transport hose, that is, an air conditioner hose), and various vibrations generated as the vehicle travels And plays a role of suppressing vibration from being transmitted from one member connected through the hose to the other member.

  By the way, the structure of the oil system, the fuel system, the water system, and the refrigerant system hose regardless of the industrial use and the automobile use, for example, a reinforcing thread is provided between the inner rubber layer and the outer rubber layer as disclosed in Patent Document 1 below. It has a structure having a braided reinforcing layer.

FIG. 7 (a) shows the structure of a refrigerant transport hose (air conditioner hose) disclosed in Patent Document 1 below, in which 200 is a cylindrical inner rubber layer, and an inner resin layer 202 is laminated on the inner side. Is formed.
A first reinforcing layer 204 is formed by spirally winding a reinforcing thread on the outer side of the inner rubber layer 200, and further, a reinforcing thread is spirally wound on the outer side via an intermediate rubber layer 206 in a direction opposite to the first reinforcing layer 204. The second reinforcing layer 208 is laminated, and the outer rubber layer 210 as the cover layer is laminated as the outermost layer.

This example is an example in which a reinforcing layer is formed by spiral braiding reinforcing yarn, but such a reinforcing layer is also formed by braiding a reinforcing yarn with a blade.
FIG. 7B shows an example thereof. In the figure, reference numeral 212 denotes a reinforcing layer formed by braiding reinforcing yarns between the inner rubber layer 200 and the outer rubber layer 210.
A resin inner layer 202 is formed further inside the inner rubber layer 200.

As shown in these figures, the hose conventionally provided in a form having a reinforcing layer is a straight cylinder having a straight shape in the axial direction on both the inner surface and the outer surface.
By the way, in the case of such a straight cylindrical hose, a certain length is required in order to ensure good vibration absorption.

Especially in the case of high pressure hoses such as oil systems (for example, power steering hoses) and refrigerant systems (refrigerant transport hoses) compared to low pressure hoses such as fuel systems and water systems, vibration absorption, The required length for reducing the propagation of sound and vibration into the room is increased.
For example, in the case of a refrigerant transport hose, even if the length of the straight line that must be connected is 200 mm, vibration absorption, sound, and vibration propagation are generally performed using a hose having a length of 300 to 600 mm. We are reducing.

  However, various devices and parts are incorporated in the engine room, and in recent years, the engine room has become more and more compact in recent years. If the hose length is long, piping design to avoid interference with others and handling when installing the hose will be a difficult task, and the piping design and handling for each model must be devised. It is a big burden.

For this reason, development of a hose that has a short hose length and can absorb vibrations satisfactorily has been demanded.
As a means for shortening the length of the hose while ensuring vibration absorption in the hose, it is conceivable to make the hose into a bellows shape.
The point which provides a bellows part in the fuel type | system | group hose of a motor vehicle is disclosed by the following patent document 2. FIG.

FIG. 8 shows the fuel system hose disclosed in Patent Document 2, in which 213 is a cylindrical rubber layer, and 214 is a resin inner layer formed on the inner surface thereof.
As shown in the figure, the fuel system hose is provided with a bellows portion 216.
Therefore, in the case of this fuel system hose, vibration can be absorbed based on the flexibility of the bellows part 216.

However, the hose in this example is used as a fuel hose, called a filler hose, and pressure resistance is not particularly required, and its burst pressure is less than 1 MPa.
Therefore, such a hose structure cannot be directly applied to a hose that requires pressure resistance.

  As a means for imparting pressure resistance to a hose having such a bellows portion, it is conceivable to provide a reinforcing layer having a large reinforcing effect. However, as a reinforcing layer for a hose having a bellows portion, the flexibility inherent to the bellows portion is considered. In addition, the reinforcing layer should be able to be easily and satisfactorily formed on the outer surface side of the inner rubber layer.

  Furthermore, pressure resistant vibration absorbing hoses, for example, hoses used for piping in automobile engine rooms, such as air conditioner hoses, in addition to pressure resistance and vibration absorbing properties, gas permeation resistance, that is, from the inside of the hose to the outside. In some cases, the hose must have gas permeability resistance in addition to pressure resistance and vibration absorption. However, in the case of a hose having a bellows part, since the surface area is increased in the bellows part, it is disadvantageous for the gas permeation resistance, and measures must be taken.

Japanese Patent Laid-Open No. 7-68659 JP 2001-74174 A

  In view of such circumstances, the present invention has been made for the purpose of providing a pressure-resistant vibration-absorbing hose that is excellent in pressure resistance and vibration-absorbing properties and also has excellent gas-permeation resistance.

  Thus, according to the first aspect of the present invention, the reinforcing layer formed by braiding the reinforcing yarn is laminated on the outer surface side of the cylindrical inner rubber layer having the bellows portion, and the reinforcing layer is positioned at the valley portion of the bellows portion. Braiding depth of the portion to be b, and trough depth in the inner rubber layer a, braiding the reinforcing yarn in the reinforcing layer so that 0 ≦ b ≦ 0.7a, and the inner rubber layer The opening angle θ of the valley is characterized by θ ≦ 100 °.

  A second aspect is characterized in that, in the first aspect, the reinforcing layer is formed by braiding the reinforcing yarn with a blade.

  A third aspect of the present invention is characterized in that, in any one of the first and second aspects, a burst pressure by pressurization is 1 MPa or more.

  According to a fourth aspect of the present invention, there is provided a piping hose according to any one of the first to third aspects, which is disposed in an engine room of an automobile.

Effects and effects of the invention

  As described above, in the present invention, the reinforcement layer formed by braiding the reinforcement yarn is laminated on the outer surface side of the cylindrical inner rubber layer having the bellows portion to constitute a pressure-resistant vibration absorbing hose.

According to the present invention, good flexibility of the hose can be ensured by the bellows part. Therefore, even when the hose length is shortened, good vibration absorbability can be ensured.
That is, according to the present invention, the length of the hose can be shortened while ensuring good vibration absorption of the hose. In the piping hose to be used, it is possible to solve the problems of piping design and routing when the hose is attached.
Furthermore, since the length of the hose can be shortened, there is an advantage that the degree of freedom of layout in piping is increased.

Further, according to the present invention, a good pressure resistance can be imparted to the hose by the reinforcing layer formed by braiding the reinforcing yarn.
That is, according to the present invention, it is possible to ensure both excellent vibration absorption and pressure resistance.

  In addition, in the present invention, since the reinforcing yarn is braided to form the reinforcing layer, there is no problem that the flexibility inherent to the bellows portion is greatly impaired by providing the reinforcing layer.

In addition, when the reinforcing layer is formed by braiding the reinforcing yarn, the reinforcing layer is continuously continuous in the circumferential direction and the longitudinal direction, unlike the case where the reinforcing layer is formed by wrapping the reinforcing cloth. Therefore, the pressure resistance of the hose by the reinforcing layer can be effectively increased.
In addition, the reinforcing layer can be easily formed during the manufacture of the hose, and the manufacturing cost of the hose can be suppressed at a low cost.

The present invention braids the reinforcing yarn so that the braid depth b of the portion located in the valley portion of the bellows portion in the reinforcing layer is 0 ≦ b ≦ 0.7a with respect to the valley depth a in the inner rubber layer, Another feature is that the opening angle θ of the valley in the inner rubber layer is θ ≦ 100 °.
That is, in the hose of the present invention, the braid depth of the portion located in the valley portion of the bellows portion in the reinforcing layer is made shallower than the valley depth in the inner rubber layer, and the gap between the valley portion and the reinforcing layer in the inner rubber layer is set. A predetermined gap is formed at the time of forming the hose.

In this hose, in a use state in which a pressure fluid is passed through the inside, a portion forming a gap between the inner rubber layer and the reinforcing layer, that is, a valley portion and an intermediate portion from the valley portion toward the mountain portion However, it deform | transforms so that it may contact | adhere directly, without interposing a reinforcement layer by the effect | action of internal pressure.
As a result, the apparent permeation area when the gas permeates from the inside of the hose to the outside, that is, the substantial permeation area is reduced, thereby reducing the gas permeation amount, and improving the gas permeation resistance in the hose. Can be effectively increased.

However, in the present invention, the braid depth b in the reinforcing layer needs to be b ≦ 0.7a with respect to the valley depth a in the inner rubber layer.
If b is larger than this, the close contact deformation due to the action of internal pressure at the valley portion and the intermediate portion in the inner rubber layer is not satisfactorily performed, and the gas permeation amount cannot be sufficiently reduced.

Similarly, when the opening angle θ of the valley in the inner rubber layer is larger than 100 °, the close contact deformation of the valley in the inner rubber layer and the subsequent intermediate portion due to the action of the internal pressure is not sufficiently performed. A sufficient reduction in the amount of permeation cannot be achieved.
Therefore, in the present invention, it is necessary to satisfy b ≦ 0.7a and θ ≦ 100 °. Note that b can be 0 or more.

In the present invention, the thickness of the peak portion in the inner rubber layer can be made larger than the thickness of the valley portion.
If it does in this way, gas permeation can be controlled well also in mountain parts other than a trough part, and the gas permeation resistance in the whole hose can be raised more effectively.

The reinforcing layer is preferably configured by braiding a reinforcing yarn with a blade.
When the blade is braided, it is desirable to control the take-up speed so that the braid angle is substantially equal between the portion located in the peak portion of the bellows portion and the portion located in the valley portion.
If the braid angle is larger than the static angle (54.7 °), the hose tends to extend in the longitudinal direction. If the braid angle is smaller than the static angle, the hose tends to extend in the radial direction. If the braid angles are not substantially equal to the part located in the part, the reinforcing effect in the reinforcing layer is different between the part located in the peak part and the part located in the valley part, and the pressure resistance may be reduced. Because there is.

The present invention is particularly effective when applied to a hose that requires pressure resistance with a burst pressure of 1 MPa or more (claim 3).
The pressure-resistant vibration absorbing hose of the present invention can be configured in a form in which a cover layer is laminated outside the reinforcing layer. Here, the cover layer can be preferably composed of an outer rubber layer.
Furthermore, the present invention is particularly effective when applied to a piping hose disposed in an engine room of an automobile (claim 4).

Next, embodiments of the present invention will be described with reference to the drawings.
1 and 2, reference numeral 10 denotes a gas-permeable pressure-resistant vibration absorption hose (hereinafter simply referred to as a hose) used as a refrigerant transport hose (air conditioner hose), for example. Shaped end 14.
This hose 10 is a laminate of a cylindrical inner rubber layer 16, a reinforcing layer 18 formed by braiding a reinforcing yarn 28 (see FIG. 3) on the outer side thereof, and an outer rubber layer 20 as an outermost cover layer. It has a structure.

  Here, PET, PEN, aramid, PA (polyamide), vinylon, rayon, metal wire or the like can be used as the reinforcing yarn 28 constituting the reinforcing layer 18.

Further, as the inner rubber layer 16, a single material or a blend material such as IIR, halogenated-IIR (Cl-IIR, Br-IIR), NBR, CR, EPDM, EPM, FKM, ECO, silicon rubber, urethane rubber, or the like may be used. it can.
However, in the case of an HFC refrigerant transport hose, an IIR or halogenated-IIR single material or a blend material is particularly preferable.

For the outer rubber layer 20, various rubber materials similar to those for the inner rubber layer 16 can be used. However, other than that, a heat shrinkable tube or a thermoplastic elastomer (TPE) can also be used. For example, acrylic, styrene, olefin, diolefin, vinyl chloride, urethane, ester, amide, fluorine, and the like can be used.
In this embodiment, the hose 10 has an inner diameter of about 5 to 50 mm (preferably 5 to 25 mm).

In the hose 10 of the present embodiment, the braid depth b of the bellows valley 18-1 in the reinforcing layer 18 in the bellows 12 in the bellows 12 is shown in FIG. It is set as 0 <= b <= 0.7a with respect to the depth a of the trough part 16-1, and the trough part 18-1 in the reinforcement layer 18 and the trough part 16-1 and trough part 16- in the inner side rubber layer 16 are set. A gap S is formed between the intermediate portion 16-3 from 1 to the mountain portion 16-2 (when the hose 10 is formed).
The opening angle θ of the valley portion 16-1 in the inner rubber layer 16 is θ ≦ 100 °, preferably θ ≦ 75 °.

The hose 10 shown in FIGS. 1 and 2 can be manufactured as follows, for example.
That is, first, the inner rubber layer 16 having the bellows is formed by injection molding or the like.

Then, as shown in FIG. 3, the inner rubber layer 16 molded as described above is extrapolated to a long mandrel (for example, a resin mandrel) 21.
Then, in this state, this is passed through the center hole of the blade braiding device 22 shown in FIG. 3, and the reinforcing yarn 28 is braided on the outer surface while feeding it.

This blade braiding device 22 has a disk-like deck plate 24 and a plurality of pairs of carriers 26A and 26B that are paired with each other along the circumference, and the carriers 26A and 26B that are paired with each other are shaped like an eight. The reinforcing yarn 28 is braided on the outer surface of the inner rubber layer 16 by rotating the deck plate 24 around its center while crossing.
In this braid braiding, the take-up speed is controlled so that the braid angles at the peak portion 18-2 and the valley portion 18-1 in the reinforcing layer 18 are substantially equal.

When the reinforcing layer 18 formed by braiding the reinforcing yarn 28 on the outer surface of the inner rubber layer 16 is laminated and formed as described above, this is continuously dipped into a dipping liquid for the outer rubber layer 20, The outer rubber layer 20 is coated on the outside.
Then, this is charged into a drying furnace and dried.

Thereafter, the mandrel 21 is extracted, and then the long molded product is cut, whereby the hose 10 shown in FIGS. 1 and 2 is obtained.
This is merely an example of manufacturing the hose 10 and can be manufactured by other manufacturing methods.

In the hose 10 of the present embodiment, good flexibility can be ensured by the bellows portion 12, and therefore good vibration absorption can be ensured even when the hose length is shortened.
That is, the length of the hose can be shortened while ensuring good vibration absorption by the hose 10, thereby solving the problems of piping design and handling when the hose is attached in the engine room of the automobile.

Furthermore, since the length of the hose can be shortened, the degree of freedom in layout when piping is increased.
In addition, good pressure resistance can be secured by the reinforcing layer 18 formed by braiding the reinforcing yarns 28 along the bellows shape.

  Further, in this embodiment, since the reinforcing layer 18 is formed by braiding the reinforcing yarn 28, the problem that the flexibility inherent to the bellows portion is not greatly impaired by providing the reinforcing layer 18 does not occur.

Moreover, since the reinforcing layer 18 can be formed in a continuous shape in the circumferential direction and in the longitudinal direction, the pressure resistance of the hose 10 by the reinforcing layer 18 can be enhanced.
In addition, the reinforcing layer 18 can be easily formed during the manufacture of the hose 10, and the manufacturing cost of the hose 10 can be reduced.

In the hose 10 of this embodiment, the braid depth b of the valley portion 18-1 in the reinforcement layer 18 is shallower than the depth a of the valley portion 16-1 in the inner rubber layer 16, and the valley portion 18 in the reinforcement layer 18. A predetermined gap S is formed between -1 and the valley 16-1 in the inner rubber layer 16 (during hose molding).
Therefore, the valley portion 16-1 and the intermediate portion 16-3 of the inner rubber layer 16 that formed the gap S at the time of molding as shown in FIG. It is deformed so as to be in direct contact with the inner pressure without interposing the reinforcing layer 18.

As a result, the apparent permeation area when the gas permeates from the inside of the hose 10 to the outside, that is, the substantial permeation area becomes small, and the gas permeation amount is reduced.
That is, the gas permeability resistance of the hose 10 is effectively enhanced by such partial adhesion deformation of the inner rubber layer 16.

〔Example〕
Hose having various configurations shown in Table 1 was manufactured, and refrigerant permeation amount (gas permeation resistance), burst pressure (pressure resistance), and flexibility were measured. The results are also shown in Table 1.

  In Table 1, the fact that the number of reinforcement layers to be driven in each hose is 3 aligned × 48 strokes indicates that three 1000 de (denier) reinforcing yarns 28 are arranged side by side and braided with 48 carriers. .

Here, the refrigerant permeation amount, burst pressure, and flexibility in Table 1 were measured under the following conditions.
<Refrigerant permeation amount>
As shown in FIG. 5, four hoses are prepared, and after attaching a 50 cc muffler 30 on one end of three of them, HFC-134a is sealed as a refrigerant in the inside by 70% of the internal volume, and the other end is sealed. The stopper 32 was sealed.
In addition, in order to investigate the change in the weight of the hose alone, the HFC-134a was unencapsulated in one of the hoses, and the change in the weight was traced with both ends sealed with plug bodies 32 as shown in FIG.

Weigh in every 24 hours up to 96 hours in a 90 ° C oven, and calculate [Refrigerant-filled hose weight reduction (96 hours-24 hours)-Hose unit weight reduction (96 hours-24 hours)] The refrigerant permeation amount per hose was determined.
The smaller the refrigerant permeation amount, the better. However, here, the refrigerant permeation amount: 1.1 g / line · 72 hr was set as the target value.

<Rupture pressure>
Water pressure was applied to the inside of the hose, the pressure was increased at a pressure increase rate of 160 MPa / min, and the pressure at the time of rupture was expressed.

<Flexibility>
As shown in FIG. 6, a hose was placed on a measuring table with a fulcrum interval of 100 mm, the center of the hose was pushed at a speed of 10 mm / min, and the peak value of the load was measured.
The softer the better, the better, but here the target value was 10 N or less.

As can be seen from the results in Table 1, both the refrigerant permeation amount and the flexibility of the present example are lower than the target values, and the gas permeation resistance and flexibility are better than those of the comparative example. Yes.
Also, the burst pressures of all of the present examples are as high as 17 MPa or more, indicating excellent pressure resistance.

Although the embodiment of the present invention has been described in detail above, this is merely an example.
For example, in the present invention, the thickness of the bellows 16-2 and the valley 16-1 of the bellows portion in the inner rubber layer 16 can be made uniform, but the thickness of the peak 16-2 is set to the valley 16-1. It can also be thicker than the wall thickness.
If it does in this way, gas permeation can be suppressed well also in peak parts 16-2 other than trough part 16-1, and gas permeation resistance in hose 10 whole can be raised more effectively.

  In the present invention, the reinforcing layer 18 may be formed by spirally winding the reinforcing yarn around the outer surface of the inner rubber layer 16, or the reinforcing layer 18 may be formed by a knit braid having elasticity. In addition, the present invention can be configured in various forms without departing from the gist of the present invention, such as various changes in the configuration of the hose 10 according to the application.

It is a perspective view which cuts and shows the hose of one Embodiment of this invention partially. It is sectional drawing of the hose of FIG. It is explanatory drawing which shows the principal part process of the manufacturing method of the hose of FIG. It is explanatory drawing which shows the effect | action of the hose of FIG. It is a figure which shows the measuring method of the refrigerant | coolant permeation amount of the hose performed for the effect confirmation of an Example and a comparative example. It is a figure which shows the method of measuring the softness | flexibility of the hose of an Example and a comparative example. It is a figure which shows an example of a conventionally well-known hose. It is a figure which shows the example of a hose different from conventionally well-known FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hose 12 Bellows part 16 Inner rubber layer 16-1 Valley part of inner rubber layer 18 Reinforcement layer 18-1 Valley part of reinforcement layer 28 Reinforcement thread a Depth of valley part of inner rubber layer b Braid of valley part of reinforcement layer Depth θ Opening angle of valley of inner rubber layer

Claims (4)

  A reinforcing layer formed by braiding a reinforcing yarn is laminated on the outer surface side of the cylindrical inner rubber layer having the bellows portion, and the braid depth of the portion located in the valley portion of the bellows portion in the reinforcing layer is b, The trough depth in the inner rubber layer is a, and the reinforcing yarn in the reinforcing layer is braided so that 0 ≦ b ≦ 0.7a, and the opening angle θ of the trough in the inner rubber layer is θ ≦ 100. A pressure-resistant vibration absorption hose with excellent gas permeation resistance, characterized in that   The pressure-resistant vibration absorbing hose excellent in gas permeability resistance according to claim 1, wherein the reinforcing layer is formed by braiding the reinforcing yarn with a blade.   The pressure-resistant vibration absorbing hose excellent in gas permeability resistance according to any one of claims 1 and 2, wherein a burst pressure by pressurization is 1 MPa or more.   The pressure-resistant vibration absorbing hose excellent in gas permeability resistance according to any one of claims 1 to 3, which is a piping hose disposed in an engine room of an automobile.

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