JPH04239629A - Manufacture of curved hose - Google Patents

Abstract

PURPOSE:To easily manufacture the above curved hose having a fiber reinforced layer in the intermediate part of section thereof. CONSTITUTION:While an inner rubber tube 12 is formed in advance and kept in a state that the rubber tube sheathes a mandrel, a fiber reinforced layer is preformed in a tubular form. The fiber reinforced layer is fitted by using the elastic force and stretching properties thereof on the outer surface of the inner rubber tube 12, then an outer rubber tube 16 is formed on the outside of the fiber reinforced layer 14 and the thus formed piece is vulcanized as a whole to obtain a curbed hose.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a hose, and more particularly to a method for facilitating the manufacture of curved hoses.

0002

[Prior Art] Rubber hoses generally have a laminated structure comprising an inner rubber tube, an outer fiber reinforcing layer, and an outer rubber tube as the outermost layer. In this method, first, an inner rubber tube is continuously extruded using an extruder, and fiber reinforcing threads are braided and continuously wound one by one on the outer peripheral surface of the tube to form a fiber reinforcing layer. The outside of the product is coated with an outer rubber tube by continuous extrusion using a second extruder, and then the extruded long product is cut into a predetermined size and then heated and vulcanized. .

By the way, some hoses are straight pipes, while others, such as automobile radiator hoses and cooler hoses, are complicatedly curved in two or three dimensions. The shape of the hole
In the case of such curved hoses, conventionally, an unvulcanized molded product extruded into a straight tube shape is inserted into a mandrel such as a metal pipe that has been bent into a predetermined shape, and the inserted state is molded. The body was heated and vulcanized, and the product hose was removed from the mandrel after vulcanization.

0004

[Problems to be Solved by the Invention] Here, the work of inserting the rubber hose formed into a straight tube shape into the mandrel has conventionally been done manually by an operator. The molded product has a considerable wall thickness when the inner rubber tube, fiber reinforced layer, and outer rubber tube are combined, and in addition, rigidity is imparted by the intermediate fiber reinforced layer, making the molded product considerably hard. Therefore, inserting the bent hose into a mandrel of a predetermined thickness is a difficult task, and this has been a major factor hindering the automation and mechanization of bent hose manufacturing. For this reason, although various studies and proposals have been made regarding manufacturing methods for such curved hoses, the reality is that no satisfactory method has yet been provided.

[0005]

[Means for Solving the Problems] The present invention has been made to solve the above problems, and its gist is to provide a fiber reinforced layer on the outside of the inner tube and a two-dimensional or three-dimensional A method for manufacturing a curved hose having an originally curved shape, in which the inner tube is pre-shaped, the fiber reinforcing layer is separately pre-shaped into a cylindrical shape, and then the pre-shaped fiber A fiber reinforced layer is formed on the outside of the inner tube by fitting the cylindrical body of the reinforcing layer onto the outer peripheral surface of the inner tube.

[0006] In the present invention, first, the inner tube of the hose is
Shape the shape. As a molding method, it is possible to adopt extrusion molding using an extruder as in the past,
Alternatively, a mandrel bent into a predetermined shape is set inside a mold using a mold, and the inner tube material is molded.
It is also possible to employ a method of molding (for example, injection molding) in which the inner tube is placed over the outer peripheral surface of the mandrel, or it is also possible to use other methods.

In the present invention, the inner tube is formed separately from the inner tube as described above, that is, the inner tube is formed in the conventional manner.
Rather than braiding and sequentially winding the fiber reinforcing yarn on the outer circumferential surface of the tube, the fiber reinforcing layer is preformed into a cylindrical shape by knitting, braiding, etc. independently of the inner tube. Thereafter, the cylindrical body of the fiber-reinforced layer preformed in this manner is fitted over the outer peripheral surface of the inner tube to form a laminated structure of the inner tube and the fiber-reinforced layer. At this time, the fiber-reinforced yarn is wound in a predetermined pattern to form a cylinder, that is, the cylindrical preform of the fiber-reinforced layer has elasticity and stretchability in the axial direction and the direction perpendicular to the axis. Therefore, it can be easily fitted onto the outer peripheral surface of the inner tube by utilizing its elasticity and stretchability. According to the above method, an assembly of the inner tube and the fiber reinforced layer can be obtained by inserting the inner tube into the mandrel, and then the outer tube can be coated on the outside of the fiber reinforced layer as necessary. If you vulcanize it as it is (in the case of rubber hose), you can create a bent hose with a specified shape.
You can get the best products.

As described above, the method of the present invention does not involve winding reinforcing threads one by one on the outer peripheral surface of the inner tube to form a fiber reinforcing layer, as in the conventional method. A preformed fiber-reinforced layer is prepared separately and is placed over the outer peripheral surface of the inner tube. According to the present invention, it is possible to form a fiber-reinforced layer on the outer peripheral surface of the inner tube with a mandrel having a predetermined shape inserted into the inner tube in advance, so that the mandrel can overcome the resistance of the fiber-reinforced layer. There is no need to insert the hose into the molded body, which simplifies the manufacturing work of the hose. This also makes it possible to mechanize and automate hose manufacturing.

In the present invention, after inserting a mandrel into the inner tube and forming a fiber reinforcing layer on the outer peripheral surface of the inner tube, the method for forming the outer outer tube is as follows. A method can preferably be adopted in which the assembly of the inner tube and the fiber reinforced layer is set inside a mold, and the outer tube material is molded into the mold in this state.

0010

Embodiments Next, embodiments of the present invention will be described in detail with reference to the drawings. In FIG. 3, reference numeral 10 denotes a curved rubber hose, and as shown in FIG.
2, a fiber reinforcement layer 14, and an outer rubber tube 16. 1 and 2 show an example of a method of manufacturing this rubber hose 10. As shown in the figure, in the method of this example, the inner rubber tube 12 is first molded independently. As shown in FIG. 2(A), the molding method involves setting a mandrel 20 of a predetermined shape inside a mold 18, and molding an inner rubber tube material into a cavity.
A molding method (for example, an injection molding method) can be suitably employed. Of course, a conventional extrusion molding method may be used as a method for forming the inner rubber tube 12, and a mandrel may be inserted into the inner rubber tube extruded in this manner.

On the other hand, as shown in FIG. 2(B), in parallel thereto, a fiber-reinforced layer 1 is formed by winding fiber-reinforced yarn into a cylindrical shape.
No. 4 preformed body 22 is molded. At that time, fiber reinforcing thread,
It is desirable to obtain the preform 22 by wrapping a polyethylene sheet around the outer peripheral surface of the holding cylinder 24, which facilitates the molding operation and improves subsequent handling. It is also possible to use a material other than polyethylene sheet as the holding cylinder 24.

Furthermore, in order to firmly fix each reinforcing thread of the preformed body 22 formed into a cylindrical shape on the outer circumferential surface of the holding tube 24, an adhesive is coated on the outer circumferential surface of the holding tube 24 in advance. You can leave it there. It is desirable to use a sheet for the holding tube 24 that has good releasability from the inner rubber tube 12.

After the preformed body 22 of the fiber reinforced layer 14 has been formed in this manner, it is then cut into a required length as shown in FIG. 2(B) (b). After the inner rubber tube 12 and the preformed body 22 of the fiber reinforced layer 14 are prepared in this way, the preformed body 22 of the fiber reinforced layer 14 is made from a vinyl chloride sheet as shown in (c). ((
d) condition). At the same time, as shown in FIG. 1(a), the molded body of the inner rubber tube 12 is held in an unvulcanized state or a slightly vulcanized state (semi-vulcanized state) together with a mandrel 20 in a jig 26.
Connect to. The cylindrical preformed body 22 of the fiber reinforcing layer 14 inserted into the jig 26 is then transferred from the jig 26 side to the inner rubber tube 12 side and inserted. At this time, since the preform 22 is a net-like body made of fiber-reinforced yarn wound into a cylindrical shape or something similar thereto, it has elasticity and stretchability in the axial direction (longitudinal direction) and in the direction perpendicular to the axis. This can be easily fitted and covered even on the inner rubber tube 12 which is three-dimensionally curved in a complicated manner. Note that the inner diameter of the preformed body 22 is set in advance by the inner diameter of the inner rubber tube 1.
It is preferable that the inner rubber tube 12 is formed to have a larger outer diameter than the inner rubber tube 12, and is extended in the longitudinal direction so as to cover the outer circumferential surface of the inner rubber tube 12. At this time, the preform 22 is expanded in the longitudinal direction to reduce its diameter.
The inner rubber tube 12 is tightly adhered to the outer circumferential surface of the tube 12.

[0014] The preformed body 22 of the fiber reinforcing yarn is placed in a jig 26.
When transferring the preform 22 to the inner rubber tube 12 side, the holding cylinder 24 made of polyethylene sheet or the like is left on the jig 26 side, and only the preform 22 is transferred to the inner rubber tube 12 side, and then held. The cylinder 24 may be removed from the jig 26 and prepared for the next process, or the holding cylinder 24 and the preform 22 may be transferred from the jig 26 side onto the outer peripheral surface of the inner rubber tube 12. After that, it may be pulled out from the inner rubber tube 12.

Furthermore, when inserting the preform 22 onto the jig 26, only the preform 22 on the holding cylinder 24 is inserted into the jig 26.
Alternatively, the holding cylinder 24 may be made of a rubber material. In this case, it is no longer necessary to transfer the preform 22 from the jig 26 to the inner rubber tube 12 together with the holding tube 24, and then to pull out the holding tube 24 from the inner rubber tube 12. It becomes possible to use it as a structure of 10.

Now, as described above, the mandrel 20 - inner rubber tube 12 - fiber reinforced layer 14 (preformed body 22
) After obtaining the assembled body, set it inside the mold 28 as shown in Fig. 1(c), and then mold the outer rubber tube material inside the mold 28 (for example, by injection molding). mold). As a result, the inner rubber tube 12,
A rubber hose 10 having a laminated structure of a fiber reinforcing layer 14 and an outer rubber tube 16 can be vulcanized and molded, and then the mold 28 is disassembled to take out the molded product and the mandrel 20
Extract. Note that the mandrel 20 can be removed mechanically from the product hose 10 using a robot hand.

Although the embodiments of the present invention have been described in detail above, this is merely an example, and the present invention can also be applied to cases where a resin pipe is used as the inner tube, and in some cases, the above-mentioned In this way, it is also possible to insert the preformed fiber-reinforced layer onto the jig or directly onto the outer peripheral surface of the inner tube without using a holding cylinder as an intermediary. Furthermore, the present invention can be applied to the manufacture of various types of hoses and hoses that are curved or bent in various shapes. It can be implemented with various modifications.

[Brief explanation of the drawing]

FIG. 1 is a process explanatory diagram of a main part of a method for manufacturing a curved hose according to an embodiment of the present invention.

FIG. 2 is another step explanatory diagram of the method for manufacturing the same hose.

FIG. 3 is an explanatory diagram of a rubber hose to which the present invention is applied.

[Explanation of symbols]

10 Bent rubber hose 12 Inner rubber tube 14 Fiber reinforcement layer 22 Preformed body

Claims (1)

[Claims] 1. A method for manufacturing a curved hose having a two-dimensionally or three-dimensionally curved shape and having a fiber-reinforced layer on the outside of an inner tube, the method comprising forming the inner tube in advance. On the other hand, the fiber reinforced layer is separately preformed into a cylindrical shape, and then the preformed cylindrical body of the fiber reinforced layer is molded into the inner tube.
By fitting the inner tube onto the outer circumferential surface of the tube,
A method for manufacturing a curved hose, characterized by forming a fiber reinforcing layer on the outside of the hose.