JP2999562B2 - Method and apparatus for manufacturing rubber hose - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a rubber hose which is vulcanized while restraining the outer periphery of an unvulcanized rubber layer with a resin coating layer.

[0002]

2. Description of the Related Art Various conventional methods and apparatus for producing rubber hoses of this kind are provided, and one of them is to restrain the inner and outer peripheral surfaces of the rubber hose with resin instead of the so-called lead vulcanization method. Resin vulcanization method (JP-A-63
182136).

[0003] To explain the schematic with reference to FIG. 6, reference numeral 1
Is a mandrel drum on which a mandrel 2 made of resin or rubber is wound, and 3 is a rubber extruder that continuously extrudes an unvulcanized inner rubber layer 4 on the outer periphery of the mandrel 2 drawn from the mandrel drum 1. Oh, this rubber extruder 3
After the fiber reinforcement layer 6 is formed on the outer periphery of the inner rubber layer 4 extruded from the braiding machine 5 by the braiding machine 5, an adhesive is applied by an adhesive application device 7, and the adhesive is further dried by a drying device 8. Next, an unvulcanized outer rubber layer 10 is extruded at a temperature of 90 ° C. from a rubber extruder 9 on the outer periphery of the fiber reinforcing layer 6 and then passed through a vacuum device 11. In the resin coating apparatus 12, a resin coating layer 13 mainly composed of polymethylpentene (4-methylpentene-1) is formed.

[0004] Subsequently, in order to maintain the shape, the resin coating layer 13 is water-cooled to 130 ° C in a cooling bath 14 and subsequently passed through a dehydrator 15, and then subjected to microwaves in a UHF heating unit 16 by microwaves. About 4 and 10 from inside
Raise the temperature to 5 ° C to 175 ° C. Next, the unvulcanized rubber hose is sent from the UHF heating device 16 to a salt bath 17 equipped with a rotating drum, where it is heated from the outside at a temperature of 160 ° C. to complete vulcanization.

[0005] Thereafter, the resin coating layer 13 is passed through a washing tank 18 and a dewatering device 19, and finally, the resin coating layer 13 is broken and removed by a resin peeling machine 20, and the obtained fiber reinforced rubber hose 21 is wound up on a winding stand and collected. It has become. The peeled resin is sent to a resin pulverizer 22 to be pulverized, returned to the resin coating device 12, and reused.

The inner rubber layer 4 swells into the outer rubber layer 10 through the fiber reinforcing layer 6 by the mandrel 2 and the resin coating layer 13 and is cured as it is.
Thus, a fiber reinforced rubber hose having an improved adhesive strength between 0 and excellent sealing properties can be obtained.

[0007]

However, in the conventional method for manufacturing a rubber hose, a resin coating layer 13 is formed around the outer rubber layer 10 and the resin coating layer 13 is
After cooling and hardening to 0 ° C., the inner and outer rubber layers 4 and 10 were heated at 135 ° C. to 17 °
Because it is designed to heat up to 5 ° C ,
When the temperature of the resin coating layer 13 rises, it softens and the strength decreases. That is, the resin material of 4-methylpentene-1 generally has a Vicat softening point of 145 ° C to 175 ° C.
Therefore, if the heat history required for vulcanization is given in a short time,
There is a possibility that the resin coating layer 13 is not only softened but also damaged. Therefore, the pressure and shape required for bonding the unvulcanized rubber hose cannot be sufficiently maintained.

Therefore, if the vulcanization temperature is set low, the vulcanization must be carried out for a long time, and the vulcanization temperature cannot be raised at the time of starting vulcanization. , 10 and the fiber reinforcement layer 6 cannot be applied with sufficient pressure, and the adhesive strength between the rubber layers 4, 10 and the fiber reinforcement layer 6 is reduced.

In addition, setting the vulcanization temperature low requires:
As described above, the vulcanization for a long time is inevitable, so that the vulcanization tank must be lengthened, which leads to an increase in the size of the entire apparatus.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. In the first aspect of the present invention, an unvulcanized rubber layer is formed on the outer periphery of a mandrel made of resin or rubber. Extruding a resin coating layer on the outer periphery of the unvulcanized rubber layer, and after cooling and curing the resin coating layer, vulcanizing the unvulcanized rubber layer by heating it with a microwave. And a method for producing a rubber hose, comprising:
During microwave vulcanization of the unvulcanized rubber layer, the outer peripheral surface of the resin coating layer is cooled by a fluid having low microwave absorption.

According to the second aspect of the present invention, there is provided an extruder for extruding an unvulcanized rubber layer on the outer periphery of a mandrel made of resin or rubber, and a resin for extruding a resin coating layer on the outer periphery of the unvulcanized rubber layer. UH for vulcanizing by heating the coating device and the uncured rubber layer inside the resin coating layer that has been cooled and cured by microwaves
And a cooling device for cooling the outer peripheral surface of the resin coating layer in the UHF heating device.

[0012]

According to the first aspect of the present invention, when the unvulcanized rubber layer in the resin coating layer is vulcanized by microwaves, the outer peripheral surface of the resin coating layer is simultaneously cooled with a fluid, whereby the resin is cured. Softening of at least the outer peripheral surface of the coating layer is prevented, and the cured state is maintained. Therefore, microwave vulcanization temperature of the unvulcanized rubber layer can be sufficiently high, it can be shortened in curing time.

[0013] According to the second aspect of the invention, is maintained cured state of the resin coating layer by the cooling device, good pressure of the unvulcanized rubber layer due to the high temperature of the microwave vulcanization temperature as described above Since the vulcanization state can be obtained, a vulcanization tank or the like using a conventional salt bath, hot air tank, or the like can be shortened or unnecessary, so that the entire apparatus can be downsized.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. Note that the same reference numerals are given to the same components as those in the related art for the description. FIG. 1 shows a manufacturing apparatus provided for the method for manufacturing a rubber hose according to the present invention. That is, in the figure, reference numeral 1 denotes a mandrel drum on which a mandrel 2 made of poly-4-methylpentene-1 is wound, and 3 denotes a main layer composed of a fluororubber material of an innermost layer and a hydrin rubber material or a hydrin rubber of a second layer on the outer periphery of the mandrel 2. A rubber extruder for extruding an inner rubber layer 4 having a predetermined thickness made of a rubber material to be formed; 5, a braid device for covering the outer periphery of the inner rubber layer 4 with a fiber reinforcing layer 6; Is a drying device, and 9 is an outer rubber layer 10 of a predetermined thickness made of hydrin rubber material on the outer periphery of the fiber reinforcing layer 6.
A rubber extruder for extrusion molding at 0 ° C., wherein the unvulcanized rubber layers 4 and 10 extruded by the rubber extruder 9 are:
After passing through the vacuum device 11, poly-4 methylpentene-1 was extruded at 270 ° C. on the outer periphery of the resin coating device 12 to form a resin coating layer 13 as shown in FIG.

Thereafter, the resin coating layer 13 is water-cooled in a cooling tank 14 to about 70 ° C. to 130 ° C., and then supplied from a dehydrator 15 to a UHF heater 16 to supply the inner and outer unvulcanized rubber tanks 4, 10.
Was heated by microwaves, and the outer peripheral surface of the resin coating tank 13 was cooled in the cooling device 30 with refrigerant air having little microwave absorption. More specifically, the cooling device 3
0 is a long UHF heating device 1 as shown in FIGS.
6, a doughnut-shaped refrigerant outlet passage 3 which is provided along the longitudinal direction inside the UHF tank 16a.
1 and the refrigerant outlet passage 3 by the air compressor 32.
1 comprises a refrigerant supply passage 33 for supplying refrigerant air, and a heat exchanger 35 provided in the middle of the refrigerant supply passage 33. The refrigerant outlet 31a is connected to the refrigerant outlet passage 3
1 is opened on the inner peripheral side, and the blowout amount is adjusted by a flow rate adjusting valve 36.

Then, the resin coating layer 13 having the unvulcanized rubber layers 4 and 10 therein is formed in the UHF tank 16a at a rate of 3 minutes per minute.
m at a speed of 180 ° C with a heating value of 3kw
And maintained this state for about 10 minutes. At the same time, the outer peripheral surface of the resin coating layer 13 is
It was forcibly cooled with 5 ° C. refrigerant air. Finally, the resin coating layer 1 is formed by the resin peeling machine 20 without vulcanizing a salt bath or the like.
The resin was removed by dividing it by 3, and the peeled resin was sent to a resin pulverizer 22 to be pulverized and returned to the resin coating apparatus 12.

Based on this manufacturing process, the resin release layer 13
Table 1 shows the results of the test when the thickness t was changed from 1.0 mm to 5.0 mm.

[0018]

[Table 1]

As is clear from this table, when the resin coating layer 13 is 1.0 mm, the workability, that is, the flexibility of the hose is good, but the inner rubber layer 4 and the outer rubber layer 10 are good.
Peel strength, that is, adhesion strength and product performance were poor, and the resin coating layer was sometimes broken.

On the other hand, under the conditions of 1.5 mm to 4.0 mm, the adhesive strength of the inner and outer rubber layers 4 and 10 was extremely good, and the workability was sufficiently good. This is the cooling device 30
As shown in FIG. 4, the temperature distribution of the resin coating layer 13 is sufficiently cooled on the outer peripheral side as compared with the inner peripheral side and becomes sufficiently hard,
This is because the inner and outer unvulcanized rubber layers 4 and 10 inside were able to be firmly held, and as a result, the microwave vulcanization temperature was 13
This is because the temperature can be raised from 5 ° C. to 175 ° C. to 180 ° C. to 200 ° C., and the pressure between the unvulcanized rubber layers 4 and 10 can be increased.

Incidentally, the results at the lowermost end of Table 1 show the adhesive strength and the like of the rubber hose manufactured according to the conventional manufacturing method, and are inferior to those obtained by the manufacturing method of the present invention in the adhesive strength.

As described above, in this embodiment, the resin coating layer 1
The strong shape retention of the unvulcanized rubber layers 4 and 10 by 3 enables microwave vulcanization in a short time,
The conventional salt bath, washing tank and dehydration tank can be unnecessary or shortened. As a result, it is possible to reduce the size of the entire device. Further, since the temperature of the resin coating layer (particularly, the portion which is easily oxidized and deteriorated in contact with air) can be kept low, the deterioration of the resin is remarkably reduced, and the cost is reduced.

The resin coating layer 13 having the unvulcanized rubber layers 4 and 10 held therein is placed in the UHF tank 16a at a speed of 5.2 m / min.
When the micro-vulcanization and the resin coating tank 13 were cooled by the cooling device 30 for 5.8 minutes while moving at the speed described above, the same operation and effect as described above were obtained.

Furthermore, using a 20 ° C. a liquid fluorocarbon e.g. n- perfluorohexane as the refrigerant fluid, UH
The same operation and effect as described above were also obtained when heating was performed at 190 ° C. for 7 minutes in the F tank 16a.

As described above, when a liquid is used as the refrigerant fluid, a cooling device 40 as shown in FIG. 5 is used.
The cooling device 40 includes a refrigerant circulation passage 41 provided integrally with the long UHF heating device 16 and disposed along the internal longitudinal direction of the UHF tank 16a.
A refrigerant supply passage 43 for supplying a refrigerant fluid to an upstream side of the refrigerant circulation passage 41, a refrigerant return passage 44 having one end connected to the refrigerant circulation pump 41 at the downstream end and the other end connected to a refrigerant pump 42, A heat exchanger 45 provided in the middle of the return passage 44, and by moving the resin coating layer 13 holding the unvulcanized rubber layers 4 and 10 through the liquid in the refrigerant circulation passage 41. Cooling.

Other fluids such as fluorocarbons, fluorochlorohydrocarbons, fluorofluorobromide, etc.
It is also possible to use liquids No. 2 to No. 2.

[0027] Incidentally, the material of the resin coating layer 13, the polypropylene in place of the poly 4-methylpentene-1, it is possible to a thermoplastic resin material such as polytetrafluoroethylene. Also, the material of the mandrel 2 can be polytetrafluoroethylene or the like, similarly to the resin coating layer 13.

[0028]

As is apparent from the above description, according to the production method of the present invention, the outer peripheral surface of the resin coating layer is cooled by a fluid having a low microwave absorption, especially during the microwave vulcanization of the unvulcanized rubber layer. As a result, the softening of the resin coating layer during the microwave vulcanization is prevented, and particularly the outer peripheral side is sufficiently cured. Therefore, the unvulcanized rubber layer can be held firmly, and the microwave vulcanization temperature can be set as high as possible. As a result, not only the adhesive strength of the unvulcanized rubber layer is improved, but also the vulcanization time can be shortened.

In addition, since the microwave vulcanizing tank is provided with a cooling device for cooling the outer peripheral surface of the resin film layer, the cooling device can sufficiently cool and cure the resin film layer as described above.
By shortening the vulcanization time, a device such as a salt bath can be shortened or made unnecessary. As a result, the size of the entire apparatus can be reduced, the degree of freedom of the installation space of the apparatus can be improved, and the cost can be reduced. Further, since the surface temperature of the resin coating layer can be lowered, there is a great effect in preventing the deterioration of the resin.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing one embodiment of a manufacturing apparatus provided for a manufacturing method of the present invention.

FIG. 2 is a sectional view showing a UHF device and a cooling device applied to the present manufacturing apparatus.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a temperature distribution diagram of a resin coating layer in a cooling device.

FIG. 5 is a sectional view showing another embodiment of the UHF device and the cooling device applied to the present manufacturing apparatus.

FIG. 6 is a schematic view showing a conventional manufacturing apparatus.

[Explanation of symbols]

 2 ... mandrel 3, 9 ... rubber extruder 4 ... inner rubber layer 10 ... outer rubber layer 12 ... resin coating device 13 ... resin coating layer 16 ... UHF heating device 30, 40 ... cooling device

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29C 35/00-35/18 B29C 47/88

Claims (2)

(57) [Claims] A step of extruding an unvulcanized rubber layer on the outer periphery of a resin or rubber mandrel; a step of extruding a resin coating layer on the outer periphery of the unvulcanized rubber layer; After cooling and curing, the step of heating the unvulcanized rubber layer with microwaves and vulcanizing the same, the method comprising the steps of: microwave vulcanizing the unvulcanized rubber layer; A method for producing a rubber hose, characterized in that the surface is cooled by a fluid having low microwave absorption. 2. An extruder for extruding an unvulcanized rubber layer on the outer periphery of a resin or rubber mandrel, a resin coating device for extruding a resin coating layer on the outer periphery of the unvulcanized rubber layer, and cooling. A UHF heating device for heating and vulcanizing the unvulcanized rubber layer inside the cured resin coating layer by microwaves, and further comprising a cooling device for cooling the outer peripheral surface of the resin coating layer in the UHF heating device. An apparatus for manufacturing a rubber hose, comprising: