JPS5852118B2 - Plastic hose fastening configuration - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Plastic hoses are increasingly being used to replace the rubber hoses that have traditionally been widely used.

There are various reasons for this, but the most notable ones are that it is lightweight, has excellent resistance to various oils and chemicals, and has a simple manufacturing process and superior workability. All of these points are noteworthy as they guarantee the conventionality of plastic hoses.

However, on the other hand, the only weak point, which can be said to be the biggest one, is that liquids such as oil leak from the fastening fittings when the operating limit temperature is about 60°C.

As is well known, the body of a plastic hose is made of nylon.
Thermoplastic inner layer (inner tube) such as Teflon,
A synthetic fiber reinforcing layer made of braided vinylon thread, nylon thread, etc., and a protective outer layer (outer) made of polyurethane, nylon, etc. are integrated as main components.In the structure where a metal fitting is fastened to the end of the rubber hose, The conventional techniques used in the past have been followed as they are.

In other words, this is done by inserting the tube end of the plastic hose between the insert, which is a metal tube inserted into the inner tube, and the socket fitting, and crimping the tube part of the socket fitting toward the inner tube. There is.

However, while the good fastening technology for rubber hoses is insufficient for plastic hoses, it has been pointed out that internal fluid often tends to leak from the fastened parts of hose fittings when used for long periods of time at high temperatures. , and it has come to be recognized that there is a limit value for its usage temperature, which is about 60° C., as mentioned above.

Inner tubes made of nylon, Teflon, etc., which form the innermost part of plastic hoses, are characterized by their strong oil and chemical resistance; It has the weakness of causing liquid leakage due to repeated use, and although the braided layer of vinylon thread and nylon thread serves as a reinforcing layer to supplement the pressure resistance of the inner tube, it does not allow liquid leakage to persist. It has nothing to compete with.

The outer layer made of an extruded coating of nylon, polyurethane, etc., which ultimately covers and protects these, has no effect, especially in maintaining the normal state of the braided reinforcing layer.

In this way, each of the three layers exhibits the characteristics of each of the three and exhibits a comprehensive effect to maintain the superiority of the plastic hose pipe body. In other words, they had a completely different problem.

In other words, using the same technology as in the case of rubber hoses, liquid leakage occurs along the surface between the hose inner and the insert under high temperature and pressure, reaches the socket of the hose fitting, and escapes.
Furthermore, it reaches the hose body through the reinforcing layer and escapes while causing the hose outer to bulge, which means that this phenomenon becomes more noticeable at high temperatures.

The present invention aims to solve the above-mentioned drawbacks by taking measures to prevent liquid leakage under high temperatures and to semi-permanently block the conveyance path, thereby contributing to further improving the status of plastic hoses. The gist of this is that a layer of cross-linked nystomer is interposed in a laminated manner only in the part where the metal fitting is attached to the plastic hose, which is composed of a metal wire as a braided reinforcing layer. Based on this, an internal stress is generated within a single layer of elastomer, and the outward action of this stress is sustained for a long time under high temperatures, and the synthetic fiber and metal wire are constructed as a braided reinforcing layer only in the part where the fitting of the plastic hose is attached. In particular, by interposing layers of cross-linked elastomer in a laminated manner, generating internal stress within the elastomer layer based on the compression and tightening of the metal fittings, and sustaining the outward action of this stress for a long period of time at high temperatures, it is possible to This means that a pressing force that cannot be exerted is strongly applied between layers, between contact surfaces, etc.

Below, we will discuss the specific actions and effects of several examples that have been implemented and found to be effective.

First, in Fig. 1, 1 is an inner tube (inner layer) made of nylon, Teflon, etc., 2 is a braided reinforcing layer made of metal wire such as galvanized iron wire or stainless steel wire, and 3 is an outer (protective outer layer) made of polyurethane, nylon, etc. ), which is installed, for example, in an extrusion molding machine, and the three layers described above are integrated to form a hose pipe body.

Reference numeral 4 denotes a metal insert inserted into the end of the inner tube 1, which is wedge-shaped as a whole, and has sawtooth-shaped annular stepped portions S to S2 formed around its fitting trunk.

Reference numeral 5 denotes a fastening socket fitting, which consists of a closing lid portion C and a collapsible tightening tube portion S.

Reference numeral 6 denotes a union for connection to the opposite hand, which is suspended from the head hook portion F of the insert 4 and placed so as to be freely rotatable.

1 is a cross-linked elastomer, which is the compressed tube portion S
The protective outer layer 3 has a tubular shape having a length approximately equal to
The material shall be fitted to the end of the material, and one of the missing materials will be adopted depending on the usage conditions and circumstances.

That is, natural rubber, butyl rubber, nitrile rubber, styrene-butadiene rubber, fluorocarbon rubber, etc. are all recognized as having qualities that are useful for the purpose of the present invention.

The illustrated state is a finished product, but when the first fittings 5 and 6 are not fitted, that is, 1.2.3
is a three-layer integrated hose pipe body, the tubular elastomer 7 is fitted to one end of the hose pipe body, and the appearance is made as a single body,
Next, 8 parts of the metal fitting 5 are fitted therein, and then a crimping operation is performed with the R dimension as the crushing and tightening range.

Therefore, the internal stress generated in the elastomer 7 exerts a strong pressure force on the surface in contact with the elastomer 1, which in turn compresses the protective outer layer 3 and increases the pressure force between the inner surface of the inner layer 1 and the outer surface of the insert 4. .

Needless to say, it is obvious that such an effect is the effect of blocking the leakage and distant path of liquid, which is the purpose of the present invention, and the qualities of the selected elastomer almost eliminate this blocking effect. It is suitable for semi-permanent use.

FIG. 2 shows another embodiment of the plastic fastening structure shown in FIG.
The same reference numerals as in the figures indicate the same or equivalent parts.

The same applies to the figure below. ) The cross-linked elastomer 1 is cut to a certain length from the end of the outer 3 and applied there as a substitute, but the feature of this case is that the internal stress generated in the elastomer 7 is completely reinforced with metal wire. Since each metal wire is sunk into the Nistomer 7 by applying it to the layer 2, it is particularly effective in strictly preventing the outer layer 3 from bulging through the reinforcing layer 2. .

In the case of Figure 1, there is no need to perform full heat processing on each of the three layers 1, 2, and 3 of the hose tube body, and it can be integrated with the metal fittings in its original shape, so it is easy to work. It is something that cannot be done.

FIG. 3 shows an embodiment of a plastic hose fastening structure according to another invention, in which one end of a plastic hose having a mixed braided reinforcing layer 8 made of synthetic fibers 81 and metal wires 82 is bridged into the socket fitting 5. They are fitted via an elastomer 7 and crimped.

Therefore, the internal stress generated in the nidistomer 7 exerts a strong pressure contact force on the surface in contact with the nidistomer 1, which in turn compresses the protective outer layer 3 and increases the contact force between the inner surface of the inner layer 1 and the outer surface of the insert 4. It is clear that this has the effect of blocking the path of liquid leakage.

FIG. 4 shows another embodiment of the fastening structure of the plastic hose shown in FIG. As an alternative, a reinforcing layer is applied on the two reinforcing layers consisting of the metal wire braided layer 2 and the synthetic fiber braided layer 9, but each metal wire braided layer 2 is inserted into the elastomer 7. As the metal wire braided layer 2 is inserted into the elastomer 7, the hose body and the entire fitting are held in an extremely firmly integrated state, and since the metal wire braided layer 2 is inserted into the elastomer 7, the outer material 3 can be seen through the reinforcing layer. Prevents swelling.

FIG. 5 shows another embodiment of the fastening structure of the plastic hose shown in FIG. 3. In order to further prevent liquid leakage and transmission at the metal part of the hose structure shown in FIG. This is a case where the ends of the outer 3 and the metal wire braided layer 2 are cut off to a certain length, and the crosslinked nidistomer 1 is applied there as a substitute, and by doing so, the metal wire braided layer 2
This is particularly effective in strictly preventing the outer layer 3 from bulging due to the passage through the outer layer 3.

In the case of Figure 3, as in the case of Figure 1, the three layers 1, 8, and 3 of the hose pipe body do not require full heat processing and can be integrated with the metal fittings in their original shape, making it easy to work. This point should also not be overlooked.

As explained above, the present invention achieves the intended purpose, but the fact that the conventional use limit temperature of 60°C was raised to 80°C to 90°C is a comprehensive explanation of the effects of the present invention. This is a simple demonstration and does not require further elaboration.

[Brief explanation of drawings]

FIG. 1 is a cutaway front view of main parts showing a fastening structure of the present invention, FIG. 2 is a cutaway front view of main parts showing another embodiment of FIG. 1, and FIG. 3 is a cutaway front view of main parts showing a fastening structure of another invention. 4 and 5 are cutaway front views of main parts showing other embodiments of FIG. 3. FIG. 1: Inner tube, 2: Metal wire braided layer, 3: Outer, 4: Insert, 5: Socket fitting, 6: Connection union, γ: Crosslinked elastomer, 8: Mixed braided layer, 81
: Synthetic fiber, 82: Metal wire, 9: Synthetic fiber braided layer, C:
Obstruction lid part, F: head end part, S: crushing and tightening part, 5lj
S2. S3' Serrated annular step.

Claims (1)

[Scope of Claims] 1. Consists of at least a plastic inner tube made of nylon, Teflon, etc., which forms an inner layer, a reinforcing layer made of braided metal wire, which forms an upper layer, and an outer plastic material, such as polyurethane, nylon, etc., which forms a protective outer layer. An insert of a metal tube inserted into the plastic inner tube at the end of the plastic hose tube that is integral as a material, a closing lid portion that comes into contact with the end face of the plastic hose tube, and a metal tube insert that is fitted onto the outside of the plastic outer tube. In this case, the socket fitting is comprised of a press-clamped pipe portion facing the insert and the inside and outside, and the crosslinked elastomer layer is compressed and compressed in a laminated manner within the crushing and tightening range of the socket fitting, and this A fastening structure for a plastic hose characterized by semi-permanently blocking a path through which an internal fluid under high temperature and pressure leaks along between laminated surfaces of a plastic hose pipe by the outward action of internal stress generated in the nidistomer itself due to compression and compression. . 2. The plastic according to claim 1, in which a single layer of cross-linked nitrogen is placed under the crushing fastening part of the socket fitting as a substitute for the part where the protective outer layer (outer) of the plastic hose pipe body has been removed, and is interposed on the reinforcing layer. Hose fastening configuration. 3 At least a plastic inner tube made of nylon, Teflon, etc. that forms the inner layer, and a vinylon thread that forms the upper layer;
The end of the hose tubular body is inserted into the plastic inner tube at the end of the integrated hose pipe body, which is made up of a reinforcing layer made of a braid of synthetic fibers such as nylon thread and metal wire, and a plastic outer material such as polyurethane or nylon that forms a protective outer layer. It has a metal tube insert, a cold protection cover portion that comes into contact with the end face of the plastic hose tube body, and a socket fitting that is fitted onto the plastic outer and is made of a collapsed tube portion that is in an internal and external facing relationship with the insert. In this product, the layer of cross-linked nidistomer is compressed and compressed in a laminated form within the crushing and tightening range of the socket fitting, and the internal circulating fluid under high temperature and pressure is The construction of the plastic hose with the characteristic of semi-permanently blocking the leakage path between the laminated surfaces of the plastic hose tube. 4. A single layer of cross-linked nitrogen is placed under the compressed and compressed portion of the socket fitting in place of the removed portion of the protective outer layer (outer) of the plastic hose tubular body, and is interposed on the reinforcing layer, as described in claim 3. Plastic hose fastening configuration. 5. A single layer of cross-linked nitrogen is placed under the compressed and compressed part of the socket fitting in place of the part where the protective outer layer (outer) and metal wire reinforcing layer of the plastic hose pipe body have been removed, and between it and the inner layer (plastic inner tube). The plastic hose fastening structure according to claim 3, characterized in that the plastic hose fastening structure is interposed.