JP2001182866A - Rubber tube for connecting refrigerant circulating conduit and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber tube for connecting a refrigerant circulating conduit which is necessary for complex bending in a narrow space in equipment. SOLUTION: The rubber tube for connecting the refrigerant circulating conduit which has steam permeation resistance whose water vapor permeability is 0.4 g/m2.24 hours or less, and which is a rubber tube comprising butyl-rubber not having transpiration of a refrigerant in use or having very small transpiration as a main component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to connection of pipes for transporting refrigerant used in cooling systems such as refrigerators, freezers, wine coolers and air conditioners, for example, copper passing through fins of a fin tube type heat exchanger of an air conditioner. Applications such as connecting pipes to make the flow of refrigerant into one pass,
TECHNICAL FIELD The present invention relates to a refrigerant pipe for connecting a refrigerant circulation pipe and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, refrigerators, freezers, wine coolers, and air conditioners generally include a compressor (compressor), a condenser (heat exchanger), a capillary tube (divider), and an evaporator, and circulate the refrigerant by the compressor. Then, a low temperature is generated by the latent heat of evaporation of the refrigerant, and a low-temperature air is sent to a desired space by a cooling blower to cool the desired space. In recent years, an electronic cooling system using a semiconductor called a Peltier element has also been found in wine coolers and the like. A copper pipe is generally used as a circulation pipe for circulating such a refrigerant, and a phosphorus-deoxidized copper pipe is used as a connector pipe for connecting desired portions such as bent portions of these pipes.

[0003] However, since these connecting pipes are made of metal, they have no flexibility and the connecting portion is weak to vibration.
When complicated bending is required in a narrow gap or when the area required for the connection work or the volume of the bulge at the connection point cannot be sufficiently secured, the connection is difficult, and furthermore, the work required for the connection is large and the work cost is high. And the like.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, and has an object to solve the following problems and to provide a rubber pipe for connecting a refrigerant circulation pipe and a method of manufacturing the same. Is to provide. Extremely little evaporation of the refrigerant (good airtightness); Even if a connecting reinforcement such as a pinch cock is not used, the connecting portion is loosened over time due to vibration or the like, and the refrigerant does not leak from the connecting portion; Able to connect the circulation pipes in the gap efficiently; not to be affected by "hot" with high-temperature refrigerant; not to be softened or sticky with time; to connect parts that require complicated bending It is possible.

[0005]

That is, the present invention mainly comprises butyl rubber having a water vapor transmission rate of 0.4 g / m ² · 24 hours or less and having no or very little refrigerant evaporation during use. It is a rubber tube for connecting a refrigerant circulation line, which is a rubber tube as a component. In a preferred aspect of the rubber pipe for connecting the refrigerant circulation pipe of the present invention, a pulling force from the connection part of 50 N or more is used without connecting reinforcement such as a pinch cock when connecting a desired part of the refrigerant circulation pipe. The connecting part tightening force can be maintained for a long period of time, and A45 to A65 soft hardness (JIS K
6253), the connection of the circulation pipeline located in the narrow space inside the equipment can be connected smoothly, and the loss of heating of 1% or less which is not affected by "temperature" of the refrigerant passing through the inside can be achieved. Have. Further, in a preferred embodiment of the rubber tube for connecting the refrigerant circulation line of the present invention, a resin-vulcanized rubber tube mainly composed of butyl rubber having heat resistance, specifically, 100% by weight of a polymer mainly composed of butyl rubber 50 to 150 parts by weight of a filler, 1 to 10 parts by weight of an activator, 3 to 20 parts by weight of a softening agent, and 5 to 20 parts by weight of a resin vulcanizing agent. A rubber tube having a three-dimensional bent shape having a desired directional angle and a bent angle with respect to the central axis of the refrigerant circulation pipe in a place where complicated bending is required in a narrow space in the device. A rubber tube that can be easily connected. The method for producing a rubber tube of the present invention is to apply a release agent to a metal core tube having a desired shape,
A green rubber tube mainly composed of butyl rubber extruded so that its inner diameter matches the outer diameter of the metal core tube is inserted, and vulcanized for a desired time in a vulcanizing can, and then vulcanized from the metal core tube. Then, the vulcanized rubber is washed and dried until the release agent adhered to the inner surface is completely removed.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto. FIG. 1 is a schematic view showing an example of a straight pipe-shaped rubber pipe for connecting a refrigerant circulation pipe, and FIG. 2 is a view in which one end of the rubber pipe is bent at a desired directional angle with respect to a longitudinal center axis of the rubber pipe. FIG. 3 is a schematic view showing an example of a refrigerant pipe for connecting a refrigerant circulation pipe which is bent at an angle. FIG. FIG. 4 is a schematic diagram showing an example of a refrigerant pipe for connecting a refrigerant circulation pipe which is bent asymmetrically at right and left angles. FIG. 4 is a view in which both left and right ends of the rubber pipe are oriented in desired directions with respect to a longitudinal center axis of the rubber pipe. FIG. 5 is a schematic view showing another example of a refrigerant pipe for connecting a refrigerant circulation pipe which is bent asymmetrically at an angle and a bending angle, and FIG. 5 shows that a substantially central portion and one end of the rubber pipe are centered in a longitudinal direction of the rubber pipe. The internal refrigerant circulation pipes are bent to the desired direction angle and bending angle, respectively. FIG. 6 is a schematic view showing an example of a bundling rubber tube, FIG. 6 is a perspective view of a metal core tube for molding and vulcanizing a rubber tube for connecting a refrigerant circulation pipe of the present invention, and FIG. 7 is a refrigerant of the present invention. FIG. 8 is a perspective view of an inspection jig for inspecting dimensions, directional angles, and bending angles of a circulation pipe connecting rubber pipe;
FIG. 3 is a diagram showing an example of use of a rubber pipe for connecting a refrigerant circulation pipe of the present invention, in which copper pipes penetrating fins of a fin tube type heat exchanger of an air conditioner are connected. In the drawings, 1 is a rubber pipe for connecting the refrigerant circulation pipe of the present invention, 2 is a metal core pipe, 3 is an inspection jig, 4
Is a copper tube, 5 is an aluminum fin, L (L ₁ + L ₂ ) is the length of the rubber tube, R is the bending angle of the rubber tube, V ₀ , V ₁ , V ₂ , V
₃ directional angle of the rubber tube, t is the thickness of the rubber tube, phi ₁ indicates the outer diameter of the rubber tube, the inner diameter of phi ₂ rubber tube, X is the center axis in the longitudinal direction of the rubber tube.

[0007] The rubber pipe 1 for connecting the refrigerant circulation pipe of the present invention has a desired shape at a desired position so that the connection of the refrigerant circulation pipe can be performed in a narrow space inside the equipment. 1 has a three-dimensional bent shape having a desired directional angle V and a bent angle R with respect to a central axis X in the longitudinal direction, for example, a straight pipe shape as shown in FIG. 1, a rubber as shown in FIG. One end of the tube 1 is bent at a desired angle V ₀ (for example, 6 degrees) and a bending angle R (for example, 20 degrees) with respect to the central axis X in the longitudinal direction of the rubber tube to have a three-dimensional bent shape. As shown in FIGS. 3 and 4, the left and right ends of the rubber tube 1 are bent at desired directional angles V ₀ and V ₁ (for example, 6 degrees and 30 degrees) with respect to the longitudinal center axis X of the rubber tube. Angled R (for example, 20 degrees), each end is asymmetrical Which has a three-dimensional bent shapes, each desired direction angle with respect to the central axis X substantially central portion near the one end of the rubber tube 1 in the longitudinal direction of the rubber tube 1 as shown in FIG. 5 V
₂ (for example, 20 degrees) and the bending angle R (for example, 20 degrees and 10 degrees)
Degrees) and a three-dimensional bent shape.

1 to 5 show a rubber tube 1 having a specific shape.
However, it is needless to say that the rubber pipe 1 for connecting the refrigerant circulation pipe of the present invention is not particularly limited to these shapes, and can be formed into any shape depending on the situation of the place of use.

Next, the size of the rubber pipe 1 for connecting the refrigerant circulation pipe of the present invention having such a shape is not particularly limited, but the thickness t at the straight pipe portion is 1.0 mm to 5 mm.
That an inner diameter phi ₂ have a size of 5mm~10mm is generally used.

On the other hand, the rubber tube 1 for connecting the refrigerant circulation pipe of the present invention has a water vapor permeability (J) of 0.4 g / m ² · 24 hours or less.
IS Z 0208). That is, the rubber tube 1 is required to be airtight, particularly water vapor permeable, from the application. This is because it is necessary to prevent evaporation of the refrigerant flowing in the circulation pipeline. As a result of intensive studies by the present inventors on this point, the water vapor permeability was 0.4 g / m ² · 24.
It has been found that the evaporation of the refrigerant can be substantially prevented if the time is equal to or less than the time.

Next, the rubber pipe 1 for connecting the refrigerant circulation line must be provided with a function of preventing the refrigerant from leaking from the refrigerant circulation line connection portion with time. In view of this point, as a result of the examination, for the connection of the desired portion of the refrigerant circulation pipeline, the pulling force from the connection portion is 50 N or more, and the tightening force of the paired connection portion is 50 N or more without using the connection reinforcement such as the pinch cock. It has been found that this function can be provided by providing the rubber tube 1 with a function that can be held for a long period of time.

Next, the refrigerant circulation pipe is often provided in a narrow space in the equipment, and it often causes difficulties such as pipe connection. As a solution to this, the hardness of the rubber tube 1 was examined variously, and as a result, the hardness of the rubber tube 1 during construction (JIS K62
It has been found that the rubber circulation pipe 53 and the rubber pipe 1 can be connected very easily when the rubber 53) has a soft hardness of A45 to A65.

Further, the rubber tube 1 contacts the circulating refrigerant, and the rubber tube 1 is also heated by the temperature of the heated refrigerant. If the extraction or evaporation of the composition mixed in the rubber tube occurs at this temperature, a phenomenon such as "rubbing" of the rubber tube occurs, which easily leads to an unexpected failure. As a result of study on this point, the heating loss of the rubber tube 1 (90 ± 3
(° C. × 168 hours) was set to 1% or less, and it was found that a phenomenon such as “burn” of the rubber tube 1 could be prevented.

Further, if the rubber tube 1 used is softened or sticky with time, dust and dirt are likely to adhere to the surface of the rubber tube 1 and loosening of the connecting portion is not preferable.

As a result of studying this point, 9
It has been found that the problem can be solved by providing heat resistance in which the rate of change in tensile strength and the rate of change in elongation are within ± 20% and the rate of change in hardness is + 10-0 in heat aging at 0 ° C. for 168 hours. On the other hand, the present inventors obtained a rubber tube 1 satisfying the various functions and performances as described above, and as a result of earnestly studying the composition of the rubber tube 1, the following composition was obtained. It has been found that a rubber tube 1 satisfying these performances and functions can be obtained.

That is, the rubber pipe 1 for connecting the refrigerant circulation line of the present invention is mainly composed of butyl rubber having heat resistance, and if necessary, ethylene propylene rubber, chloroprene rubber, chlorosulfonated polyethylene, chlorinated polyethylene, chlorinated butyl rubber. 100 blended with one or more rubbers appropriately selected from butyl rubber, brominated butyl rubber, etc.
If necessary, carbon black is used in parts by weight, and fillers are appropriately selected from white fillers such as clay, white carbon, calcium carbonate, magnesium carbonate, and talc.
1 to 10 parts by weight of an activator selected from zinc oxide, magnesium oxide, and the like, and 3 parts by weight of a softener selected from a plasticizer, process oil, polybutene, and the like.
A resin vulcanizing agent 5 selected from a resin such as a methylolated alkylphenol formaldehyde resin (polymethylol phenol resin) containing -20 wt. It is composed of a composition containing up to 20 parts by weight.

If necessary, an antioxidant, a lubricant such as wax, or a processing aid such as stearic acid can be appropriately added to the above-mentioned composition.

The reason why butyl rubber was selected as the main component in this compounding was mainly to maintain airtightness (water vapor permeability) and soft hardness. The reason for using a specific resin as the vulcanizing agent was that butyl rubber compounding was used. In order to avoid this, heat resistance is given by resin vulcanization to prevent the rubber tube 1 from sticking and softening due to the aging of the rubber tube 1 and to decrease the tightening force with the lapse of time. It was cancer.

Further, the reason why the amount of the filler is 50 to 150 parts by weight based on 100 parts by weight of the polymer is that if the amount of the filler is less than 50 parts by weight, there is a problem in the processability such as the extrudability of the tube. If the amount exceeds the weight part, the mechanical performance of the obtained rubber tube may be reduced, and the pulling force from the connecting tube may not be able to secure 50 N or more.

The reason why the amount of the softening agent to be blended is 3 to 20 parts by weight is not preferable if the amount is less than 3 parts by weight because processability such as extrudability is inferior, and if it exceeds 20 parts by weight, it is 1% or less. This is because a necessary heating loss (90 ° C. × 168 hours) cannot be obtained, and there is a possibility that the rubber pipe 1 may cause a “waste” or the like.

Next, a method for manufacturing the rubber pipe 1 for connecting the refrigerant circulation pipe according to the present invention will be described. For example, as shown in FIG. After applying a release agent to a metal core tube 2 having a desired shape such as a three-dimensional bent shape having a bending angle R with V, the metal core tube 2 is extruded so that its inner diameter matches the outer diameter of the metal core tube 2. After inserting a green rubber tube containing butyl rubber as a main component and vulcanizing it in a pressure vulcanizer at, for example, 5 kg × 30 minutes, the vulcanized rubber tube 1 is extracted from the metal core tube 2.
Next, the vulcanized rubber tube 1 is washed until the release agent attached to the inner surface of the vulcanized rubber tube 1 is completely removed, and after washing, dried and dried. Get.

The washing and drying for removing the release agent can be continuously performed by adopting a belt conveyor system.

The thus obtained rubber tube 1 for connecting a refrigerant circulation line of the present invention is inserted into an inspection jig 3 previously formed in the same shape as shown in FIG. And the bending angle R are checked for errors.

The thus-formed rubber pipe 1 for connecting a refrigerant circulation line according to the present invention is used for connecting a refrigerant circulation line requiring a complicated bend in a narrow gap in the apparatus.
For example, as shown in FIG. 8, the copper tubes 4 penetrating through the aluminum fins 5 of the fin tube type heat exchanger of the air conditioner are connected to each other, and are used for the purpose of making the flow of the refrigerant into one pass.

[0025]

EXAMPLE Using the composition shown in Table 1, the inner diameter was 7.5 m.
m, extruded rubber tube wall thickness 2.5 mm, as shown in FIG. 3 shape (direction angle _{V 0} 6 _{degrees, V} 1 30 degrees, the bending angle R20 °, the length _L 1 _{320mm, L} 2 40mm)
To form a rubber tube for connecting the refrigerant circulation pipeline. When the performance and function of the rubber tube thus obtained were measured, the results shown in Table 2 were obtained.

[0026]

[Table 1]

[0027]

[Table 2]

As shown in Table 2, the rubber pipe for connecting the refrigerant circulation pipe of the present invention had excellent performance and function as the rubber pipe for connecting the refrigerant circulation pipe.

[0029]

The rubber pipe for connecting the refrigerant circulation pipe according to the present invention has the above-described structure, and therefore, the following effects can be obtained. (1) Evaporation of the refrigerant circulating inside is extremely small. (2) Even without using a connecting reinforcement such as a pinch cock,
The connection portion does not loosen over time due to vibration or the like, and the refrigerant does not leak from the connection portion. (3) The circulation pipeline can be easily connected in the narrow gap. (4) "Erase" does not occur even when the temperature of the refrigerant circulating inside rises. (5) Does not soften or become sticky due to aging over time. (6) It is possible to easily connect the refrigerant circulation pipeline at a place where complicated bending is required in a narrow gap in the device.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a rubber pipe for connecting a refrigerant circulation pipe having a straight pipe shape according to the present invention.

FIG. 2 is a schematic view showing an example of a rubber pipe for connecting a refrigerant circulation pipe having a curved pipe at one end according to the present invention.

FIG. 3 is a schematic view showing an example of a rubber pipe for connecting a refrigerant circulation pipe having both ends curved in the present invention.

FIG. 4 is a schematic view showing another example of a rubber pipe for connecting a refrigerant circulation pipe having both ends bent in the present invention.

FIG. 5 is a schematic diagram showing an example of a refrigerant pipe for connecting a refrigerant circulation pipe which is bent from a substantially central portion according to the present invention.

FIG. 6 is a perspective view of a metal core tube for molding and vulcanizing the rubber tube for connecting the refrigerant circulation pipeline of the present invention.

FIG. 7 is a perspective view of an inspection jig for inspecting the size, direction angle, and bending angle of the rubber tube for connecting the refrigerant circulation pipeline of the present invention.

FIG. 8 is a diagram showing a usage example using a rubber pipe for connecting a refrigerant circulation pipe of the present invention.

[Explanation of symbols]

One bending angle V ₀ which refrigerant circulation pipe connecting rubber tube 2 metal core tube 3 inspection jig 4 copper tube 5 aluminum fins L (L1 + L2) the length R rubber tube rubber tube of the present invention, _V 1, _{V 2 ,} V ₃ longitudinal center of the rubber tube inner diameter X rubber tube having an outer diameter phi ₂ rubber tube thick phi ₁ rubber tube direction angle t rubber tube axis

Continuation of the front page (72) Inventor Kashino Matsuoka 3-20-28 Tachibana, Nishinari-ku, Osaka-shi, Osaka Kyowa Co., Ltd. (72) Inventor Katsuhide Kato 3--20-28 Tachibana, Nishinari-ku, Osaka-shi, Osaka Kyowa Co., Ltd. (72) Inventor Ryota Son 100 Yusan-dong, Yangsan-si, Gyeongnam, Republic of Korea F-term (reference) 3H111 AA02 BA13 BA34 CB30 DA26 DB09 DB19 DB25 EA04 EA12

Claims (9)

[Claims] 1. A rubber tube having a water vapor permeability of 0.4 g / m ² · 24 hours or less, and having butyl rubber as a main component and having no or very little refrigerant evaporation during use. A rubber tube for connecting refrigerant circulation lines. 2. A rubber capable of maintaining a tightening force of a connecting portion with a withdrawal force of 50 N or more from a connecting portion for a long period of time without using a connecting reinforcement such as a pinch cock when connecting a desired portion of a refrigerant circulation pipeline. The rubber pipe according to claim 1, wherein the rubber pipe is a pipe. 3. A rubber pipe having a soft hardness of A45 to A65 (JIS K6253) at the time of construction and capable of connecting a circulation pipe portion located in a narrow gap in the device easily. Item 3. A rubber pipe for connecting a refrigerant circulation pipeline according to Item 1 or 2. 4. The rubber tube according to claim 1, wherein the rubber tube has a heating loss of 1% or less, which is not affected by the temperature rise of the refrigerant passing through the inside of the tube. Rubber pipe for connecting the refrigerant circulation pipeline. 5. The rubber tube for connecting a refrigerant circulation line according to claim 1, wherein the rubber tube is a resin-vulcanized rubber tube mainly composed of butyl rubber having heat resistance. 6. A polymer 10 containing butyl rubber as a main component.
0 to 50 parts by weight of filler and 0 to 10 parts by weight of activator
The rubber tube for connecting a refrigerant circulation line according to claim 5, wherein the rubber tube is a rubber tube containing 3 parts by weight, 3 to 20 parts by weight of a softening agent, and 5 to 20 parts by weight of a resin vulcanizing agent. 7. A rubber tube having a three-dimensional bent shape having a desired directional angle and a bent angle with respect to a longitudinal center axis of a rubber tube at a desired position, wherein the rubber tube has a narrow gap in a device. And a rubber pipe which can easily connect a refrigerant circulation pipe at a place where a complicated bend is required.
7. The rubber pipe for connecting a refrigerant circulation pipeline according to any one of 6. 8. After applying a release agent to a metal core tube having a desired shape, a green rubber tube mainly composed of butyl rubber extruded so that the inner diameter matches the outer diameter of the metal core tube is inserted. Then, after vulcanizing for a desired time in a vulcanizing can, a vulcanized rubber tube is extracted from the metal core tube, and then the vulcanized rubber is washed until the release agent attached to the inner surface is completely removed, The method for producing a rubber pipe for connecting a refrigerant circulation pipe according to any one of claims 1 to 7, wherein the rubber pipe is dried. 9. The refrigerant according to claim 8, wherein the metal core tube has a three-dimensional bent shape having a desired directional angle and a desired bending angle with respect to a longitudinal center axis at a desired position. A method for producing a rubber pipe for connecting a circulation pipe.