GB2147971A - Hose - Google Patents

Abstract

A hose comprises a hose body 5 made of a resin material and a protective body 9 made of an elastic material, the hose body 5 has end portions 6, 7 and a flexible portion 8 connected in integral relationship to the opposite end portions 6, 7, and the hose body 5 is thinner than the opposite end portions 6, 7. The protective body 9 covers the outer periphery of the flexible portion 8 of the hose body 5 and is disposed in integral relationship on the flexible portion 8. Accordingly, the hose of the present invention has flexibility and strength, and can be assembled firmly to a counterpart with ease. <IMAGE>

Description

SPECIFICATION Hose This invention relates to an improvement in a hose made of a resin material.

Conventionally, a hose or pipe made of a resin material and having a relatively large thickness and a hose or pipe made of a resin material and having a relatively small thickness are known. However, the former lacks flexibility while the latter cannot be mounted firmly on a carrier nor has sufficient strength.

Accordingly, it has been difficult to employ such a conventional pipe or hose made of a resin material in, for example, an automobile.

Accordingly, where a hose is to be coupled firmly to another part, normally a rubber hose is used which comprises, as shown in Fig. 3 of the accompanying drawings, securing pipes 1 and 2 (which especially for an automobile are metal pipes), a rubber hose member 3 in which the pipes 1 and 2 are fitted, and a coupling 4 (particularly a metal coupling) for securing each of the securing pipes 1 and 2 to the rubber hose member 3. However, in such a conventional rubber hose with a pipe, the pipes 1 and 2 and the rubber hose member 3 are not in integral relationship, and assembly operations therefor are troublesome.

According to the present invention there is a hose comprising a hose body made of a resin material and having end portions in the form of a pipe and a flexible intermediate portion in the form of a pipe connected in integral relationship to said end portions and having a thickness of material smaller than that of said end portions; and a protective body made of an elastic material and covering the outer periphery of said flexible intermediate portion of said hose body, said protective body being disposed in integral relationship on said flexible portion.

In brief, a hose of the present invention comprises a hose body made of a resin material and a protective body made of an elastic material. The hose body has opposite end portions in the form of a pipe and a flexible portion in the form of a pipe connected in integral relationship to the opposite end portions, and the hose body is thinner than the opposite end portions. The protective body covers an outer periphery of the flexible portions of the hose body and is disposed in integral relationship on the flexible portion.

Some embodiments of the present invention will now be described by way of examples, with reference to the accompanying drawings, in which: Figure 1 is a longitudinal sectional view of a hose according to the present invention, which has no bent portion at either of the end portions thereof; Figure 2 is a longitudinal sectional view of another embodiment of a hose according to the present invention, which has a bent portion at one end thereof; and Figure 3 is a longitudinal sectional view of a conventional rubber hose with secured metal pipes.

In particular, a hose according to the present invention is characterised by a hose body made of a resin material and having end portions in the form of a pipe and a flexible portion in the form of a pipe formed integrally with the end portions and having a thickness of material smaller than that of the end portions, and a protective body made of an elastic material and covering the outer periphery of the flexible portion of the hose body, the protective body being disposed in integral relationship on the flexible portion.

A hose body of the invention is made of a resin material and has opposite end portions in the form of a pipe and a flexible portion in the form of a pipe connected in integral relationship to the opposite end portions and having a thickness of material smaller than that of the opposite end portions.

The hose body may be in the form of any pipe wherein the opposite end portions and the flexible portion are connected in integral relationship to each other, and the configuration thereof is not limited to a particular one.

In other words, the length of the hose body (the length of each of the end portions and the flexible portion), the cross-sectional shape), the inner and outer diameters, and so on, are not limited to particular ones. However, the thickness of the hose body is relatively large at the end portions and relatively small at the flexible portion. The thickness at the end portions may be such as to provide sufficient rigidity to allow the end portions to be securely mounted on or connected to respective counterparts. Meanwhile, the thickness at the flexible portion may be such as to provide sufficient flexibility which may be required for a particular application of the hose.

It is to be noted that, while the thickness of the hose body varies for the application of the hose and depending upon the kind of resin material used and so on, where the resin material is 6.6-nylon, normally the thickness at the opposite end portions may preferably be 2 mm or so while the thickness of the flexible portion may preferably be 0.5 mm or so.

The hose of the present invention will be described with respect to two preferred embodiments thereof. On one hand, the hose of the invention may have no bent portion at either of the end portions 6 and 7 thereof as shown in Fig. 1, and on the other hand, it may have a bent portion 62 at one end portion 61 as shown in Fig. 2. It is to be noted that the configuration of such a bent portion 62 is not limited to a particular one, either.

An extremity of each of the end portions may have a coupling portion 63 formed thereon, for example as illustrated in Fig. 2. The configuration of the coupling portion 63 may be any one selected from different ones in accordance with the kind or type of counter member or part to which it is to be connected, the mounting means used, and so on.

In particular, the configuration of the coupling portion 63 may be that of a screw thread or a flange or the like, or it may comprise a nut or the like which is a coupling part made of a metal material or the like may be mounted or the coupling portion when the hose is used. It is to be noted that, even if the end portions are in the form of a pipe which has no specific configuration for coupling as shown in Fig. 2, it is possible that they exhibit a function as a coupling means.

Each of the opposite end portions may have a flared portion 64 which acts as a locating means on a counterpart, and such a flared portion 64 may be reinforced by a metal plate.

The resin material which constitutes the hose body may be any kind which provides a particular rigidity to the end portions and flexibility to the flexible portion and is not limited to a particular one. Thus, the resin material may be any one selected from the group consisting of polyethylene, polypropylene, polystyrene, polyvinyl chloride, methacrylate resin, 6-nylon, 6.6-nylon, 1 2-nylon, polycarbonate, polyacetal, polybutylene terephthalate, polysulfone, polyphenylene oxide, hard polyurethane, and so on. It is to be noted that where the end portions are integrally connected to the flexible portion by fusion welding, the resin material of the opposite end portions may be a material of a similar kind which can be fuse welded to the resin material of the flexible portion.

The outer periphery at least of the flexible portion is covered with a protective body made of an elastic material. The protective body 9 can cover part of the outer periphery of the end portions 6 and 7 as shown in Fig.

1, or it can cover only the outer periphery of the flexible portion 81 as shown in Fig. 2.

The protective body 9, 91 must be sufficient to protect the flexible portion against external and internal forces and to maintain the flexibility of the hose. Accordingly, the elastic material may be either a rubber material, such as natural rubber, polybutadiene, styrene-butadiene rubber, and so on, or a soft elastic resin material, such as soft polyurethane, soft polyvinyl chloride, and so on. It is to be noted that the protective body 9, 91 may be made of a foamed material of rubber or resin or of a non-foamed material of rubber or resin. The protective body 9, 91 may further be covered with a wire, mesh or the like if necessary. The thickness of the protective body 9, 91 must only be such as to allow such functions as described above and is constituted in integral relationship to the flexible portion and so on which are covered thereby.

In production of the hose of the invention, a hose body having opposite end portions and a flexible portion is moulded in continuous and integral relationship. Although the moulding process varies depending upon the kind of resin material used. the presence or absence of a bent portion at the end portions, the thickness of material at the flexible portion, and so on, in case the resin is a thermoplastic resin, extrusion moulding may be employed.

Although injection moulding or pouring moulding may be used where each of the opposite end portions has a bent portion.

otherwise opposite straight end portions of a hose body produced by extrusion moulding may be subjected to a bending operation.

The protective body can be moulded, where the material is foamed soft polyurethane, in integral relationship by pouring into a metallic mould. The foaming step may be any one conventionally employed. It is to be noted that where the protective body is made of a rubber material which requires vulcanization, the hose body made of any of the resin materials as described above must necessarily be stable against the vulcanization temperature. However, in case of cold vulcanization, the resin material need not necessarily have heat resisting property.

A body of a hose of the invention is relative thick at opposite end portions thereof while it is relatively thin at an intermediate flexible portion thereof. Accordingly, the hose of the invention can be assembled securely to a counterpart and have sufficient flexibility.

The hose body is made of a resin material and therefore, the hose of the present invention can be used as a hose which carries a substance to which rubber cannot be applied or which attacks rubber. Since the many different kinds of resin applicable to the hose of the invention provides a greater width of choice compared with rubber, different hoses for various applications can be produced very easily.

Moreover, a hose of the invention has a protective body made of an elastic material.

Accordingly, the hose is not damaged against the flexibility of a flexible portion thereof and is thus protected against an internal and an external force. Therefore, the hose of the invention is excellent in strength.

Furthermore, a conventional rubber hose with a pipe requires coupling or fastening of individual parts thereof to each other, because of the separation of the opposite end portions and a bent portion. However, the hose of the present invention does not require the coupling or fastening of individual parts thereof to each other, because the opposite end portions and the bending portions are integrally connected.

Two preferred embodiments and their method of manufacture will now be described.

A hose as shown in Fig. 1 constitutes one embodiment. The hose includes a hose body 5 having opposite end portions 6 and 7 which are straight and an intermediate flexible portion 8 in the form of a pipe connected in integral relationship to the opposite end portions 6 and 7, and a protective element 9 covering an outer periphery of the flexible body 8. Extremities of the opposite end portions 6 and 7 have a same configuration, and have an inner diameter of 6 mm, a thickness of 2 mm, and a length of 100 mm. The flexible portion 8 has an inner diameter of 6 mm, a thickness of 0.5 mm, and a length of 300 mm. The protective body 9 has an inner diameter of 7 mm, a thickness 7 mm, and a length of 320 mm. The material of the hose body is 6.6-nylon, and the protective element is made of a foamed soft polyurethane material.

A process of producing the hose described above will be described below.

At first, the hose body having the configuration as described above is produced by extrusion moulding, using 6.6-nylon as a material.

It is to be noted that the flexible portion 8 of the hose body is produced at a reduced resin supplying speed and at an increased extracting speed when compared with the opposite end portions 6 and 7. After being cooled, the hose body is placed into a cavity of a metallic mould having a predetermined shape. Then, while compressed air is blasted into the pipe, polyether polyol, freon (a foaming agent) and a catalyzer as polyol side components and methylenediisocyanate prepolymer as an isocyanate side component are put into the remaining space of the cavity and are mixed therein so that they may immediately react with each other at the temperature of 30 to 60 C of the mould to form the protective body 4 made of a foamed polyurethane rubber material.

Since the hose body forming a principal part of the hose of the present invention has the opposite end-portions and the flexible portion integrally connected to the opposite end portions and the flexible portion integrally connected to the opposite end portions, it provides a very good sealing property. Besides, the resin material of the hose body is nylon, it is relatively good in heat resisting property and in solvent resistance comparing with rubber.

Another embodiment of the present invention shown in Fig. 2 comprises a hose body made of 6.6-nylon and a protecting body 91 made of a soft polyurethane rubber. The hose body has a coupling portion 63 and a flared portion 64 on an outer periphery, opposite end portions 61 and 71, and a flexible portion 81. The hose body is produced by injection moulding. And, the protecting body 91 is produced by placing the hose body into a cavity of a mould and putting two liquid soft polyurethane rubber into the remaining space of the cavity. The hose of this embodiment as well as the hose shown in Fig. 1, has excellent flexibility and can be assembled firmly to a counterpart with ease.

Claims (5)

1. A hose comprising a hose body made of a resin material and having end portions in the form of a pipe and a flexible intermediate portion in the form of a pipe connected in integral relationship to said end portions and having a thickness of material smaller than that of said end portions; and a protective body made of an elastic material and covering the outer periphery of said flexible intermediate portion of said hose body, said protective body being disposed in integral relationship on said flexible portion.

2. A hose as claimed in claim 1, in which each of said end portions of said hose body has a coupling means formed at an extremity thereof.

3. A hose as claimed in claim 1 or claim 2, in which said resin material of said hose body is selected from the group consisting of polyethylene, polypropylene, polystyrene, polyvinyl chloride, methacrylate resin, 6-nylon, 6.6-nylon, 12-nylon, polycarbonate, polyacetal, polybutylene terephthalate, polysulfone and polyphenylene oxide.

4. A hose as claimed in any preceding claim, in which said protective body is made either of a rubber material selected from the group consisting of natural rubber, polybutadiene and styrene-butadiene rubber, or of a soft resin material selected from the group consisting of soft polyurethane and soft polyvinyl chloride.

5. A hose substantially as hereinbefore described with reference to and as illustrated in Fig. 1 or Fig. 2 of the accompanying drawings.