JPS6010898B2 - Hose manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously manufacturing a hose with excellent oil resistance and heat resistance by using a thermoplastic resin material as a core layer and covering this with a rubber layer.

Conventionally, when manufacturing rubber hoses containing thermoplastic resin as a core layer as described above, the process of manufacturing general rubber hoses was exactly the same, that is, thermoplastic resin was mixed with unvulcanized rubber. The cylindrical body that became the hose was molded in a coated state, and then the cylindrical body was removed from the molding equipment and carried into a curing pot, where it was heated and vulcanized, making it possible to manufacture products only from rubber materials. A disadvantage that had not been seen as much of an issue with hoses used in the past was that thermoplastic resins tend to soften when heat is applied during rubber vulcanization. moreover,
During vulcanization, external pressure from pressurized steam is applied, and among the rubber and thermoplastic resin materials that make up the cylindrical body, the rubber material hardens through vulcanization while the thermoplastic resin is deformed by the external pressure. It had the disadvantage that it became a deformed version.

In addition, it is possible to continuously manufacture hoses of indefinite length using continuous molding equipment, and when manufacturing long hoses, there is a limit to the capacity of the vulcanization pot, so it is difficult to manufacture long hoses. This in itself is difficult, and in reality it was impossible to manufacture a very long hose. Furthermore, when attempting to continuously mold a long hose, if the rubber is unvulcanized or the thermoplastic resin is not cured, the rotational force of the former may not be sufficiently transmitted to the end of the long hose. This also made it difficult to manufacture long hoses.

Furthermore, when attempting to integrally and continuously mold a long hose using rubber and resin, it is important to note that resin and resin or rubber and rubber have good compatibility and that external pressure can be applied using a presser roller or the like. As a result, the molding process takes a relatively short time, and the length of the hose molding process using the molding device is also relatively short. In order to avoid deformation, it is difficult to apply external pressure to the bonding surface between the rubber layer and the resin layer during the molding process, and as a result, the molding process must be maintained for a relatively long period of time. If the former used to maintain the molded state for such a long period of time has a high hose-like body feeding speed to improve the efficiency of hose production, the hose feeding length will be long and cantilevered. It was difficult to support the mold, and it was necessary to reduce the feed rate and carry out inefficient continuous molding operations.

The technical problem to be solved by the present invention is that in manufacturing a hose having a thermoplastic resin as a core layer and a rubber layer covering the core layer, a hose forming process, a vulcanizing process, and a cooling process are required. An object of the present invention is to obtain a method for manufacturing a hose that is devised so as to be able to continuously and efficiently manufacture sufficiently long hoses while avoiding deformation of the hoses through an effective combination of the present invention and the present invention.

The technical means of the present invention taken to solve the above problems are as follows:
Unvulcanized rubber mixed with a vulcanizing agent and a thermoplastic resin are extruded as a belt-like body with the thermoplastic resin layer covered with a rubber layer, and the extruded belt-like body is spirally wound on a former to form a cylinder. The cylindrical body is forcibly fed in a spiral direction while being formed into a cylindrical body, and then the formed cylindrical body is heated and vulcanized on a former, and after the vulcanization treatment is cooled on the former.

■ Since the process is heated and vulcanized during the molding process on the former, the unvulcanized rubber, which is in the shape of a shard before the vulcanization process, is subjected to vulcanization treatment to improve plowability and shape retention during the molding process. Therefore, it is possible to reliably prevent deformation of the hose due to its own weight during the vulcanization process, as in the case of vulcanization in a vulcanization pot after the molding process. Even when vulcanized, the resin layer is covered with a rubber layer with improved shape retention, so the resin layer may be deformed by heating due to the good shape retention of the rubber layer itself. Definitely easy to avoid.

■ Since the rubber is cooled on the former, the contraction effect of the rubber during cooling is effectively utilized.
During cooling, the rubber layer that covers the outside of the resin layer begins to cool first, making it possible to apply surface pressure to the joint surface between the outer rubber layer and the core layer of thermoplastic resin that covers this rubber layer. As a result, it is possible to promote the adhesion between the rubber layer and the resin layer under pressure, and to efficiently manufacture hoses while avoiding reductions in work efficiency such as reducing the hose feeding speed by formers as much as possible. I can do it. ■ The rubber material that constitutes the hose is vulcanized and hardened on the former, and the thermoplastic resin is hardened by cooling on the former, so the rotational force of the former can be easily transmitted to the end of the hose. It is possible to continuously mold a sufficiently long hose while suppressing deformation due to bending during the process.

Embodiments of the present invention will be described in detail below with reference to the drawings.

First, by the method of the present invention, as shown in FIG.
A method for manufacturing a reinforced rubber hose in which a spiral reinforcing wire rod 2 made of thermoplastic resin is inserted as a core layer within the wall thickness a will be described.

As shown in Fig. 1, an unvulcanized rubber 1 mixed with a vulcanizing agent and a hard resin reinforcing wire 2 are inserted into the die a of an extrusion molding machine A, with the latter 2 buried within the thickness of the former 1. The strip 3 is continuously extruded. Extrusion molding machine A
Inside, the unvulcanized rubber is kept at about 60 qo or less, the reinforcing wire 2 is kept at about 130 to 180 qo, and the band 3 extruded from the die a into the atmosphere is about 10,000 qo.

The pressure inside the die a is set at 100 to 200 k9/c Sakaki. At the time when this band-shaped body 3 is formed, due to the heating for extrusion molding, the physical properties of the unvulcanized rubber change to those that are more ballistic than those at room temperature, and the entire circumference of the reinforcing wire 2 is changed. It is attached throughout.

The band-shaped body 3 is spirally wound on the former B with its side edges overlapped inside and out, and is formed into a hose-shaped body 4 (cylindrical body).

A heating device 5A is installed inside the former B, and a heating device 5B is installed inside the outer periphery of the intermediate portion in the longitudinal direction of the former B, and a vulcanizing device 6 is configured by these heating devices 5A and 5B. The hose-like body 4 is fed by the former B, and is heated to about 170 to 220 qo from both the inside and outside by the heating devices 5A and 5B, while being kept in shape by the former B, and continuously heated to about 170 to 220 qo. be done. The heating devices 5A and 58 are not installed on the free end side of the former B that protrudes from the vulcanizing device 6, and a cooling device is installed on the outer periphery of the former B in the protruding portion. The hose-like body 4 after vulcanization is immediately cooled by the cooling water jetted from the cooling water spouting nozzle 7, and then cooled to room temperature while floating on the long water tank 8. The reinforcing wire village 2 is cured to form a reinforced rubber hose as shown in FIG.

Incidentally, when the above method was carried out using the following materials, it was found that the adhesion (bonding force) between the rubber la and the reinforcing wire 2 was large, and both la and 2 were easily peeled off even with repeated bending deformation. A rubber hose with no reinforcement was obtained.

Hard resin reinforcing wire 2...Unvulcanized rubber mixed with hard vinyl chloride vulcanizing agent 1...Nitrile rubber 70
Parts Other rubber (SBR) 30 parts Carbon 70 parts Softener 20 parts Vulcanizing agent 1.5 parts Other additives Slightly This means that hard vinyl chloride and nitrile rubber have good compatibility (SP values are close) This is thought to be due to the synergistic effect between the two being pressed in the melted and softened state by the pressure during extrusion molding.

In addition, when the reinforcing wire 2 is made of polypropylene or polyethylene, ethylene propyrolene terpolymer or butyl rubber is suitable as the rubber for increasing the bonding strength due to the SP value.

The former B is a former in which two or more feed rollers rotated in the same direction are inclined in the same direction with respect to the axis of the hose-like body to be formed, {〇} Same direction. A plurality of rowhoos that are rotationally driven are arranged on the same circumference and parallel to the axis of the hose-like body to be formed, and the cam surface of the outer roller provided near the roller group or the base of each roller is Former N that sends out a hose-like body using a cam, etc. formed by sequentially shifting the position in the direction of the rattan core at the end. A group of multiple rotating shafts arranged in a cylindrical shape around one cylindrical rotating shaft or on the same circumference. A belt or the like is spirally wound around the cylindrical rotating shaft, and both ends of the belt or the like are connected to each other in the hollow part of the cylindrical rotating shaft or the hollow part of the rotating shaft group to form an endless spiral rotating body. A former 6 that spirally winds the band 3 around the outer periphery of the spiral rotating body and sends it out while forming it into a hose-like body.
Each of the plurality of rotating shafts arranged on the same circumference is covered with a sleeve that can only slide back and forth in the direction of the core, and the band-shaped body 3 is spirally wound around the outer periphery of these sleeve groups to form a hose-like structure. In addition, each sleeve is divided into two halves in a semi-cylindrical shape, and when the two semi-cylindrical sleeve portions come into contact with the inner surface of the hose-like body 4, they are moved in the feeding direction. An appropriate form of former B is employed, such as a former configured to slide and send out the hose-like body 4 by sliding in the opposite direction when it reaches a position away from the inner surface of the hose-like body 4. However, in the illustrated embodiment, former B is configured as follows.

That is, as shown in FIGS. 2 to 4, one end of the core bar 9 is inserted into a sleeve li made of a thermally conductive material screwed onto the frame 10, and held in a cantilevered state. Fixedly supported, a plurality of flexible feed rollers 12 are attached to the outer peripheral surface of the core metal 9 in a spiral shape inscribed in a virtual cylindrical surface (inner peripheral surface of the hose-like body to be formed) via a holding frame 13. The rollers 12 are arranged in a shape such that each roller 12 is rotatable about its local axis in the localization layer.

The holding frame 13 has a polygonal shape as shown in FIG. It is fixed to the core bar 9 by tightening the core bar 9. By shifting the phase of each holding frame 13 by a fixed angle of 8 from the cantilever side end of the core bar 9 to the free end and fixing it, the feed roller 12.・The helical pitch can be adjusted arbitrarily.

The base end of each feed roller 12... is connected via a coupling 16 to one end of a passive shaft 15... which is rotatably inserted and supported by the frame 0, and is connected to the end of the passive shaft 15... The main gear 18 and the adjacent pinion gears 19 are fixed to the drive shaft 17, and as the drive shaft 17 is rotated by the input from the booley 20, each feed roller 12... is rotated in the helical direction. It is configured to rotate in the opposite direction.

The inner heating device 5A is constructed by providing a plurality of holes in the core metal 9 and inserting nichrome wire heaters into these holes, as shown in FIGS. 4 and 5, A and A. A structure in which a nichrome wire heater is attached to the outer peripheral surface of the core metal 9, a structure in which an oil passage is formed in the core metal 9 and high temperature oil heated by an external heat source is circulated through this oil passage, and other forms. Various specific structures adapted to the format B can be adopted.

The outer heating device 5B is composed of a plurality of infrared lamps, but other structures such as a nichrome wire heater can be adopted as appropriate.

Further, if heating and vulcanization can be sufficiently performed using only one of the inner and outer heating devices 5A or 5B, it is sufficient to provide only one, and it is not necessary to heat from both the inner and outer sides.

[Brief explanation of the drawing]

The drawings show an embodiment of the method for manufacturing a hose according to the present invention,
Figure 1 is a schematic front view showing the manufacturing process, Figure 2 is a plan view,
Fig. 3 is a front view, Fig. 4 is a longitudinal sectional front view of the main part, Fig. 5 A is a longitudinal sectional side view of the main part, and Fig. 6 is a partial cutaway of the reinforced rubber hose manufactured by the method of the present invention. It is a front view. 1... Unvulcanized rubber, 2... Thermoplastic resin, 3... ．． ．． Band-shaped body, 4...Cylindrical body, B...
...former. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. Unvulcanized rubber 1 mixed with a vulcanizing agent and thermoplastic resin 2 are extruded as a strip 3 with the thermoplastic resin layer covered with a rubber layer, and the extruded strip is placed on former B. The cylindrical body 4 is formed into a cylindrical body 4 by force feeding in the spiral direction, and then the formed cylindrical body 4 is heated and vulcanized on a former, and after being vulcanized, it is cooled on a former B. A method for manufacturing hoses.