U.S. patent application number 09/838656 was filed with the patent office on 2001-09-06 for hose assembly/and method for making same.
Invention is credited to Martucci, Norman S., Mathew, Boney A..
Application Number | 20010018933 09/838656 |
Document ID | / |
Family ID | 22906940 |
Filed Date | 2001-09-06 |
United States Patent
Application |
20010018933 |
Kind Code |
A1 |
Martucci, Norman S. ; et
al. |
September 6, 2001 |
Hose assembly/and method for making same
Abstract
A method of making a hose assembly (10) includes the steps of
disposing a reinforcing layer (14) having interstitial spaces
extending therethrough about a tubular inner liner (12) and heating
an outer surface (16) of the inner liner (12) to cause it to melt
and disperse into the interstitial spaces of the reinforcing layer
(14) and the fibers themselves to bond the first layer to the inner
liner (12). A lightweight hose assembly (10) of the type adapted
for conveying fuels and other corrosive fluids is also disclosed.
The assembly (10) includes a tubular inner liner (12) including a
melt extrudable polymeric fluorocarbon material having an external
surface (16). A layer (14) having gaps extending therethrough is
disposed about the inner liner (12). The inner liner (12) is
dispersed into the layer (14) and bonds the layer (14) to the
external surface (16) of the inner liner (12).
Inventors: |
Martucci, Norman S.;
(Clarkston, MI) ; Mathew, Boney A.; (Clarkston,
MI) |
Correspondence
Address: |
Kohn & Associates
Suite 410
30500 Northwestern Highway
Farmington Hills
MI
48334
US
|
Family ID: |
22906940 |
Appl. No.: |
09/838656 |
Filed: |
April 19, 2001 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
09838656 |
Apr 19, 2001 |
|
|
|
09240536 |
Jan 29, 1999 |
|
|
|
Current U.S.
Class: |
138/125 ;
138/126; 138/141 |
Current CPC
Class: |
B29C 48/09 20190201;
F16L 11/086 20130101; B29K 2105/0827 20130101; B29L 2023/005
20130101; B29C 48/21 20190201; B29K 2105/108 20130101; B29C 48/022
20190201; B29C 48/15 20190201; B29C 48/00 20190201; B29L 2009/00
20130101; B29K 2027/18 20130101; B29K 2027/12 20130101; F16L 11/085
20130101; B29D 23/001 20130101; B29K 2309/08 20130101 |
Class at
Publication: |
138/125 ;
138/141; 138/126 |
International
Class: |
F16L 011/00 |
Claims
What is claimed is:
1. A method for constructing a hose assembly (10), said method
comprising the steps of: disposing a reinforcing layer (14) having
interstitial spaces extending therethrough about a tubular inner
liner (12) and dispersing an outer surface (16) of the inner liner
(12) into the interstitial spaces of the reinforcing layer (14) and
bonding the first layer (14) to the inner liner (12).
2. A method as set forth in claim 1, including the step of
extruding a tubular inner liner (12) comprising a melt extrudable
fluorocarbon polymeric material and having an internal passageway
(22) defined by an inner surface (15) thereof.
3. A method as set forth in claim 1, wherein said disposing step is
further defined as braiding a reinforcing layer.
4. A method as set forth in claim 2, further including the step of
preventing flow of the inner surface (15) while allowing flow of
the outer surface (16).
5. A method as set forth in claim 4 further including the step of
cooling the internal passageway (22).
6. A method as set forth in claim 5, wherein said cooling step is
further defined as disposing a fluid into the internal passageway
(22).
7. A method as set forth in claim 6, wherein the fluid is a
gas.
8. A method as set forth in claim 6, wherein the fluid is a
liquid.
9. A method as set forth in claim 6, wherein the fluid is
cooled.
10. A method as set forth in claim 4 further including the step of
maintaining expansion of the inner liner (12).
11. A method as set forth in claim 10, wherein said maintaining
step further includes pressurizing the internal passageway
(22).
12. A method as set forth in claim 10, wherein said pressurizing
step is defined as disposing fluid into the internal passageway
(22).
13. A method as set forth in claim 12, wherein the fluid is a
gas.
14. A method as set forth in claim 12, wherein the fluid is a
liquid.
15. A method as set forth in claim 12, wherein the fluid is
cooled.
16. A method as set forth in claim 1, including the additional step
of disposing a second layer (18) about the reinforcing layer
(14).
17. A method as set forth in claim 16, wherein the second layer
(18) includes a braided reinforcing material.
18. A method as set forth in claim 17, wherein the material is one
from the group consisting essentially of stainless steel, glass,
Aramid fiber, PVDF or PPS fiber.
19. A method as set forth in claim 1 further including the step of
affixing at least one end fitting (20) to the hose assembly
(10).
20. A hose assembly (10) comprising: an extruded, smooth bore
tubular inner liner (12) comprising a melt extrudable polymeric
fluorocarbon material having an external surface and a reinforcing
layer (14) having gaps extending therethrough disposed about said
external surface (12), said inner liner (12) being dispersed in
said reinforcing layer (14) and bonding said reinforcing layer (14)
to said external surface of said inner liner (12).
21. An assembly (10) as set forth in claim 20, wherein said
assembly is free of additional polymeric fluorocarbon
dispersions.
22. An assembly as set forth in claim 20 characterized by a
reinforcing layer (18) disposed about said reinforcing layer (14)
for increasing the strength and bending properties of said hose
assembly (10).
23. An assembly (10) as set forth in claim 21 further characterized
by said reinforcing layer (14) having an outer periphery, said
inner liner (12) extending from the outer periphery of said
reinforcing layer (14) radially inwardly toward said inner liner
(12).
24. An assembly (10) as set forth in claim 20 further characterized
by said reinforcing layer (14) including a tightly wound
non-metallic material.
25. An assembly (10) as set forth in claim 24 further characterized
by said non-metallic material including one from the group
consisting essentially of glass fiber, aramid, PVDF, and PPS
fiber.
26. An assembly (10) as set forth in claim 20 further characterized
by said outer reinforcing layer (18) including a metallic
material.
27. An assembly (10) as set forth in claim 26 further characterized
by said metallic material including stainless steel.
28. An assembly (10) as set forth in claim 20 further characterized
by said melt extrudable polymeric fluorocarbon material including
perfluorinated ethylene-propropylene.
29. An assembly (10) as set forth in claim 20 further characterized
by said melt extrudable polymeric fluorocarbon polymer including
perfluoralkoxy.
30. An assembly (10) as set forth in claim 20 further characterized
by said melt extrudable polymeric fluorocarbon material including
perfluoralkoxy fluorocarbon resin.
31. An assembly (10) as set forth in claim 20 further characterized
by said melt extrudable polymeric fluorocarbon material including
one from the group consisting essentially of a polymer of
ethylenetetrafluoroethyl- ene, PVDF and THU.
32. An assembly (10) as set forth in claim 20 further characterized
by said inner liner (12) including an integral conductive (24)
means coextensive with the length of said inner liner (12) for
conducting electrical charges along the length of said inner liner
(12).
33. An assembly (10) as set forth in claim 22 further characterized
by said integral conductive means (24) including carbon black.
34. An assembly (10) as set forth in claim 20 further characterized
by including coupling means (20) adapted to engage the ends of said
hose assembly (10) for interconnecting said hose assembly (10) to a
flow of fluid.
Description
TECHNICAL FIELD
[0001] The subject invention relates to hose construction. More
specifically, the subject invention relates to a method for
constructing a hose assembly having an inner fluorocarbon polymer
liner and reinforcing layer thereabout.
BRIEF DESCRIPTION OF THE RELATED ART
[0002] Hose assemblies for conveying fuel and other corrosive
materials are well known in the art. Such assemblies are exposed to
a variety of fuel mixtures, fuel additives, and caustic materials
in addition to being exposed to extreme temperatures. Thus, such
hose assemblies must be resistant to chemical, environmental, and
physical degradation as a result of chemical exposure,
environmental exposure to heat, and physical degradation resulting
from bending and repeated movement or forces applied to the
assembly.
[0003] Polymeric fluorocarbon materials such as
polytetrafluorethylene possess the requisite chemical and
temperature resistant properties for most fuel hose applications.
Unfortunately, polymeric fluorocarbon materials exhibit relatively
poor tensile and hoop strengths. As a consequence, such
fluorocarbon materials are prone to kinking. Such kinking remains
permanent and provides a continual resistance to the fluid flow
through the hose assembly. Moreover, as a result of a fluorinated
material's low tensile strength, attachment or securing of coupling
members to the hose assembly is substantially compromised.
[0004] Various approaches have been described for offering
additional strength to a polymeric fluorocarbon liner. One approach
involves braiding fibers about the inner fluorocarbon liner. The
braided fibers offer additional strength to the fluorocarbon liner
resulting in a hose assembly that resists kinking. Examples of such
approaches are disclosed in U.S. Pat. No. 5,124,878 issued Jun. 23,
1992, U.S. Pat. No. 5,142,782, issued Sep. 1, 1992, and U.S. Pat.
No. 5,192,476 issued Mar. 9, 1993, all assigned to the assignee of
the subject invention.
[0005] The hose assembly described in the '878 patent includes an
inner fluorocarbon polymeric liner, a braided reinforcing layer
disposed about the exterior of the inner liner, and is
characterized by including an organic polymeric material dispersed
in the reinforcing layer which connects the reinforcing layer to
the inner liner thereby providing a hose assembly which is stronger
and more kink resistant.
[0006] Both the '782 and '476 patents disclose methods for
producing a hose assembly of the type shown in the '878 patent. The
'782 patent discloses a method of making a lightweight hose
assembly including the steps of extruding an inner liner, applying
a braided reinforcing material having gaps extending therethrough
about the inner liner. The inner liner and the braided layer are
then passed through a reservoir containing a solution of a
fluorocarbon polymer. After the solvent is removed, the
fluorocarbon polymer coating is dispersed throughout the braided
layer and bonds the braided layer to the inner fluorocarbon
liner.
[0007] The '476 patent discloses a method of forming a hose
assembly in which an inner liner of a fluorocarbon material is
extruded and then passed through a reservoir containing a
dispersion including a fluorocarbon polymer material. A reinforcing
layer is then braided about the exterior of the inner liner to form
a braided layer having the dispersion thereabout such that the
dispersion penetrates the interstitial spaces of the braided layer.
Subsequently, the assembly is heated to remove the solvent and the
braided reinforcing layer is then bonded to the fluorocarbon
polymer inner liner.
[0008] The methods disclosed in the '782 and '476 patents yield a
highly desirable and excellent performing hose assembly, however,
the steps of applying the fluorocarbon polymer dispersion to the
inner liner can allow some of the fluorocarbon polymer dispersion
to enter the interior of the hose where it may cause problems when
the hose assembly is used in a desired application. Additionally,
the hose assemblies discussed above preferably utilize non-melt
extrudable fluorocarbon polymers for the inner liner. These
non-melt extrudable fluorocarbon polymer materials typically
possess a higher permeation rate than do melt extrudable
fluorocarbon polymer materials. That is, the ability of volatile
fluids or gases to escape through the wall of the inner liner is
greater with non-melt extrudable fluorocarbon based hose
assemblies. Additionally, non-melt extrudable fluorocarbon
materials are not as easily adapted to recycling or reuse of the
material as are melt-extrudable fluorocarbon materials.
[0009] An additional example of strengthening an inner fluorocarbon
liner with an outer liner while also increasing flexibility is
shown in U.S. Pat. No. 3,023,787 to Phillips et al. The Phillips et
al. patent discloses a convoluted hose assembly having a
fluorocarbon inner liner constructed of many layers of helically
wrapped Teflon.RTM. tape. Convoluted hoses are typically employed
because they provide flexibility to a fluorocarbon hose assembly,
however, convoluted hose assemblies have inherent weaknesses. A
reinforcing strip consisting of reinforcing fibers coated with a
plastic material is wrapped about the inner layer to provide
additional strength to the assembly due to the inherent weakness of
wrapped convoluted core construction. In its final assembly, a
metal braid is applied to the outside of the hose assembly to
impart greater strength.
[0010] Hose assemblies of the type described in the Phillips et al.
patent have several inherent drawbacks. First, because the inner
liner is formed by helically wrapping layers of a fluorocarbon
tape, it requires a greater amount of fluorocarbon material to be
utilized in order to construct the inner liner which adds to both
the cost of constructing the hose assembly and to the labor
intensity of constructing the hose assembly. Other drawbacks
associated with hoses of the type disclosed in the Phillips et al.
patent includes failure of seams created by helically wrapping
layers of Teflon.RTM. tape. These failures occur due to inherent
weaknesses in bonding the seams created by the overlapping layers
of tape which, under internal pressures and prolonged movement are
prone to leakage or to bursting. In addition, the seams create
undulations within the inner liner which cause disruption in the
flow of liquids therein which could give rise to increased
electrical charge buildup within the hose.
[0011] Therefore, it would be desirable to have a method for
constructing a fluorocarbon hose assembly which eliminates the
necessity for liquid fluorocarbon polymer dispersions in order to
bond reinforcing layers to a fluorocarbon liner.
[0012] Further, it would be desirable to have a hose assembly which
includes a polymeric fluorocarbon inner liner which is resistant to
kinking while additionally possessing greatly increased bending
properties while maintaining the overall integrity of the hose
assembly.
SUMMARY OF THE INVENTION AND ADVANTAGES
[0013] In accordance with the present invention, there is provided
a method for constructing a hose assembly. The method includes the
steps of disposing a reinforcing layer having interstitial spaces
extending therethrough about a tubular inner liner and dispersing
the reinforcing layer into the interstitial spaces and bonding the
reinforcing layer to the inner liner.
[0014] Additionally, accordingly to the present invention, there is
provided a hose assembly including an extruded, smooth bore tubular
inner liner including a melt extrudable polymeric fluorocarbon
material having an external surface and a reinforcing layer having
gaps extending therethrough disposed about the external surface.
The external surface of the inner liner is dispersed into the
reinforcing layer and bonds the reinforcing layer to the external
surface of the inner liner.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Other advantages of the present invention will be readily
appreciated as the same becomes better understood by reference to
the following detailed description when considered in connection
with the accompanying drawings wherein:
[0016] FIG. 1 is a perspective view of the preferred embodiment of
the present invention;
[0017] FIG. 2 is an enlarged sectional view of the hose
assembly;
[0018] FIG. 3 is a perspective view of an alternative embodiment of
the present invention;
[0019] FIG. 4 is a perspective view of the extrusion of the inner
liner of the method of the preferred embodiment of the present
invention;
[0020] FIG. 5 is a perspective view of the hose assembly having a
hose attached thereto; and
[0021] FIG. 6 is a perspective view of the hose assembly with the
administration of both heating and cooling elements to ensure
adhesion of the braid layer.
DETAILED DESCRIPTION OF THE INVENTION
[0022] A hose assembly made in accordance with the present
invention is generally shown at 10 in FIG. 1. The assembly 10
includes a tubular inner liner 12 and a reinforcing layer 14
disposed about the inner liner 12. A coupling means 20 adapted to
engage the ends of the hose assembly 10 may be included.
[0023] The tubular inner layer 12, as best shown in FIGS. 1 and 2,
includes a melt extrudable polymeric fluorocarbon material
resistant to both chemical and heat degradation, thus allowing a
variety of fluids, particularly automotive fuels and fuel
additives, e.g., detergents, alcohols, etc., to pass through the
inner liner 12 without corroding or degrading the inner liner 12.
The inner liner 12 is preferably extruded using well known melt or
paste extrusion techniques and has a wall thickness between 0.001
and 0.120 inches. The walls of the inner liner 12 define an inner
surface 15 and an interior passageway 22 of the inner liner 12.
Although the inner liner 12 may be made of any number of polymeric
fluorocarbon materials, the inner liner 12 is preferably made from
a melt extrudable fluorocarbon polymeric material including
perfluorinated ethylene-propylene (FEP), copolymer of
tetrafluoroethylene and hexafluoropropylene sold under the
trademark TEFLON.RTM. FEP by DuPont, perfluoroalkoxy fluorocarbon
resins (PFA), the copolymer of tetrafluoroethylene-perfluorovinyl
ether sold under the trademark TEFLON.RTM. PFA by DuPont, or the
copolymer of ethylene tetrafluoroethylene (ETFE) sold under the
trademark TEFZEL by DuPont. In addition to the aforementioned
polymeric fluorocarbon materials, any other melt extrudable
fluorocarbon polymeric materials known to those skilled in the art
can be used. Aside from the manufacturing benefits detailed herein,
utilizing melt extrudable materials allows for any scrap melt
extrudable material to be remelted and thereby recycled within the
manufacturing facility. Another benefit of utilizing a melt
extrudable inner liner 12 is that it lowers the permeation rate of
gas and/or liquids through the hose assembly 10. Paste extrudable
fluoroplastic such as PTFE, during sintering process, may have
voids which in turn may have higher permeation.
[0024] The liner 12 is extruded to provide an inner liner 12 which
has a smooth bore, free of undulations and seams which can cause
turbulence of fluid flow within the inner liner 12. Turbulence can
cause build-up of electrical charge within the hose assembly which
is undesirable in the situation where potentially flammable fluids
are being transported therethrough. Extruding the inner liner 12
creates an inner liner 12 which as no seams and undulations and is,
therefore, the preferred method for forming the inner liner 12.
[0025] By melt extrudable fluorocarbon polymeric material, it is
meant that the material, at suitable conditions such as raised
temperature, can be caused to melt or flow such that the
fluorocarbon material flows about the reinforcing layer 14 and
substantially encapsulates the reinforcing layer 14 whereupon
cooling of the fluorocarbon material, the inner liner 12 and the
reinforcing layer 14 are bond to one and other forming an integral
hose assembly.
[0026] The assembly 10 includes the reinforcing layer 14 having
gaps extending therethrough. Generally, the reinforcing layer 14 is
constructed of a braided or woven material. Because the inner liner
12 is made of a melt extrudable material, it allows for the use of
monofilament braid material for the reinforcing layer 14 which is
significantly less expensive than multifilament braid material. The
layer 14 can comprise any non-metallic material disposed in
interleaving fashion or wrapped tightly about the inner liner 12.
The material that the layer 14 is constructed of is generally a
braid or weave of interlocking fibers which create gaps or
interstitial spaces which facilitate the connection of layer 14 to
the inner liner 12. Preferably, the material used for the layer 14
is glass fiber such as fiberglass. Glass fibers provide the
necessary strength needed to reinforce the inner liner 12 and are
heat resistant which is important for use in high temperature
environments. The layer 14 adds tensile strength to the hose
assembly 10, and the layer 14 imparts increased hoop strength to
the hose assembly 10.
[0027] In a preferred embodiment, the glass fibers are tightly
woven such that the gaps and spaces between the adjacent fibers are
minimized.
[0028] The glass fibers are preferably woven at a neutral braid.
This angle is preferred since there is no movement of the hose
under internal pressure in either the longitudinally or
diametrically. It is preferred that the braid angle is as close to
the neutral angle as possible. However, variations in materials,
selection of reinforcing fiber material, and the machines used to
apply the braid in part some variation.
[0029] The reinforcing layer 14 is preferably applied about the
exterior of the inner liner 12 by utilizing a braiding machine well
known in the art. The machine includes a plurality of spools which
carry the fiber material. The fibers are fed through the machine to
a braiding area. In the braiding area, the fibers are braided or
wound about the inner liner 12 to form the braided reinforcing
layer 14. Alternatively, the braided reinforcing layer 14 also can
be constructed in a pre-made, sock-like fashion and then can be
applied about the exterior of the inner liner 12.
[0030] Due to the chemical inertness and general lubricious nature
of polymeric fluorocarbon materials, relative movement between
inner and outer concentric polymeric fluorocarbon liners is often
encountered in prior art hose assemblies. This relative movement
leads to weakness in the final hose assembly. The present hose
assembly 10 is modified to eliminate such relative movement between
the inner liner 12 and the layer 14.
[0031] The hose assembly 10 is constructed such that the melt
extrudable fluorocarbon material which forms the inner liner 12
also bonds the reinforcing layer 14 to the inner liner 12 to form
an integral assembly and thereby eliminate relative movement
between the inner liner and the reinforcing layer 14.
[0032] As stated above, the inner liner 12 is constructed of a
material, which, when heated to a desired temperature, 500.degree.
F.-750.degree. F., the external surface 16 of the inner liner 12
melts and flows into the gaps or interstitial spaces of the
reinforcing layer 14 and about the fibers which comprise the
braided material to form a mechanical bond which integrally forms
the reinforcing layer 14 to the inner liner 12. That is, heat is
applied to the external surface 16 of the inner liner 12 by a
mechanism such as a forced air heating unit.
[0033] The material comprising the inner liner 12 is heated such
that substantially only the external surface 16 becomes fluid
enough to flow into and about the reinforcing layer 14. Heating of
the external surface 16 is controlled in a manner which does not
allow the inner surface 15 of the inner liner 12 nor substantially
all of the wall thickness of the inner liner 12 to become heated
enough to become fluid, melt, or deformed.
[0034] In order to further control the bonding of the layer 14 to
the inner liner 12, the interior passageway 22 of the inner liner
12 can be pressurized and/or cooled to prevent the interior
passageway 22 and inner surface 15 of the inner liner 12 from
becoming deformed or imprinted with the braid pattern of the layer
14. By maintaining a positive pressure in the interior passageway
22 of the inner liner 12 during the heating of the external surface
16, uniformity of the inner liner 12 can be controlled and/or
maintained. The internal pressure is preferably in the range of
1-100 psi.
[0035] Bonding of the layer 14 to the inner liner 12 can also be
enhanced by cooling the interior 22 of the inner liner 12 while
applying heat thereto. The interior 22 of the inner liner 12 can be
cooled by, for example, passing a fluid, or gas having a
temperature lower than the melting temperature of the particular
melt extrudable fluorocarbon material, through the interior 22 of
the inner liner 12. The cooling fluid can be a gas, a liquid or any
other fluid or combination of fluids suitable for this purpose. For
example, the fluid can be air or water.
[0036] Generally, the fluid is chosen such that it is compatible
with the desired melt extrudable fluorocarbon material and such
that it will not cause problems if residual cooling fluid is left
in the hose assembly 10. The temperature range for the cooling
fluid can range from -40.degree. F.-200.degree. F. using fluids
such as nitrogen, helium, etc.
[0037] The coolant can also be applied under pressure, as described
above, to accomplish simultaneous heating of the exterior 16 of the
liner 12, and cooling of the interior 22 of the inner liner 12. An
example, air or water maintained at a temperature less than the
melting temperature of the melt extrudable polymer can be
pressurized to a pressure (eg. 50 ps.) sufficient to maintain the
integrity and dimension of the inner liner 12 while simultaneously
preventing the flow or melting of the inner surface 15 of the inner
liner 12.
[0038] The hose assembly 10 is then subsequently sintered at a
suitable temperature (approximately 700.degree. F.) to cure the
fluorocarbon polymer material dispersed throughout the layer 14.
The sintering operation fuses the fluorocarbon polymer material of
the inner liner 12 to both the layer 14 and the inner liner 12.
[0039] The bond between the layer 14 and the inner liner 12
prevents slippage, i.e., relative longitudinal or rotational
movement between the inner liner 12 and the layer 14. That is, the
material melted from the inner liner 12, disperses throughout the
layer 14 and mechanically bonds the layer 14 to the inner liner 12
thereby providing strength to the inner liner 12 upon bending of
the hose assembly 10. Thus, by using a melt extrudable polymeric
fluorocarbon inner liner 12 which is dispersed throughout the layer
14, a hose assembly 10 is produced which results in the hoop
strength of the inner liner 12 being increased such that the inner
liner 12 can be bent without kinking. Further, bonding together the
inner liner 12 and the layer 14 allows the hose assembly 10 to
operate at higher working pressures and, therefore, to accommodate
fluids transported under greater pressures.
[0040] An optional metallic braided outer liner or painted layer
18, as best shown in FIGS. 1 and 2, can be disposed about the layer
14. The metallic braided layer 18 includes a metallic material for
increasing the strength and flexibility of the hose assembly 10.
More specifically, the metallic outer layer 18 allows the inner
liner 12 to be bent to smaller radii without kinking. The outer
metallic layer 18 provides strength to the inner liner 12 upon
bending. This is commonly referred to as hoop strength. Thus, by
disposing the outer metallic layer 18 about the layer 14 and the
inner liner 12, the hoop strength of the inner liner 12 is
increased, thus improving the bend radius of the hose assembly 10.
Improvement in the bend radius allows the hose assembly 10 to be
manipulated or placed into configurations which would impinge or
kink the inner liners of prior art hose assemblies. That is, the
metallic outer layer 18 allows for a reduction in the static bend
radius of the hose assembly 10 thereby allowing the hose assembly
10 to be utilized in a greater number of applications.
Additionally, the metallic outer layer 18 adds to the burst
strength of the hose assembly. The metal outer layer 18 allows the
hose assembly 10 to be used in applications where the hose assembly
10 is operated at much higher operating pressures without bursting
of the hose assembly 10. Further, the metallic outer layer 18
provides for more positive affixation of couplings or end fittings
20 to the hose assembly 10 as shown in FIG. 1. The metallic outer
layer 18 additionally increases the tensile strength that the hose
assembly 10 sufficiently to fixedly connect the coupling member 20
(FIG. 1) to the hose assembly 10.
[0041] The outer metallic layer 18 can be made of any suitable
metal material. In the preferred embodiment of the hose assembly
10, the outer layer 18 is made from stainless steel. The metallic
outer layer 18 is preferably braided in place over the reinforcing
layer 14. The metallic braided outer layer 18 is preferably applied
about the exterior of the reinforcing layer 14 by utilizing a
braiding machine well known in the art. The machine includes a
plurality of spools which carry appropriately sized stainless steel
wire material. The stainless steel wire is fed through the machine
to a braiding area. In the braiding area, the wires are braided or
wound about the exterior of the reinforcing layer 14.
Alternatively, the metallic braided layer 18 also may be
constructed in its entirety in a sock-like fashion and then applied
about the exterior of the reinforcing layer 14. Unlike the layer
14, the metallic braided outer layer 18 is not bonded to any of the
underlying structure. That is, the braided metallic outer layer 18
is not affixed to the underlying hose assembly. The braided layer
18 can be applied utilizing a braiding machine which is commonly
known as a maypole braider or may be applied using a rotary braider
which is commonly known in the art. Each machine applies the braid
differently, however, achieve the same results, that is, a Z over
Z, construction.
[0042] As fluid flows through the inner liner 12, electrical
charges can build up throughout the length of the inner liner 12.
In order to prevent these electrical charges from accumulating, the
inner liner 12 can include an integral longitudinal conductor 20
co-extensive with the length of the inner liner 12 for conducting
an electrical charge along the length of the inner liner 12. The
integral conductor 24 includes a conductive strip 24 of carbon
black, as shown in FIGS. 1 and 2. The integral conductor can also
be interspersed throughout the inner liner 12 by intermixing carbon
black 26 throughout the polymeric fluorocarbon material either
while the inner liner 12 is extruded or prior to the extrusion of
the inner liner 12 as shown in the Figures.
[0043] The hose assembly 10 can further include a coupling 20 as
shown in FIG. 1. The coupling 20 is adapted to engage the ends of
the hose assembly 10 for interconnecting the hose assembly 10 to a
flow of fluid, e.g., fuel flow to and from a fuel tank (not shown).
Couplings suitable for use with the hose assembly 10 of the present
invention are well known in the art. Typically, the couplings 20
are adapted to engage the ends of the hose assembly 10. Typically,
the couplings are adapted by way of barbs which engage the inner
surface 15 of the inner liner 12.
[0044] The coupling 20 can also include an engaging portion (not
shown) extending longitudinally from the insert portion for
engaging a fitting (not shown). The engaging portion can comprise a
male threaded member 28 or female threaded member (not shown). The
engaging portion can comprise any configuration that will cooperate
with the member to which it is connected with. For example, the
engaging portion can comprise a socket to receive a mating ball
joint (not shown).
[0045] Alternatively, the coupling 20 can be molded, such as by
injection molding, to the hose assembly (not shown). The melt
extrudable material allows for plastic fittings to be molded
directly onto the hose assembly 10 thereby eliminating crimping,
and its associated disadvantages, as the preferred method of
affixing fittings to the hose assembly 10. This makes it possible
to eliminate the separate operations of hose manufacturing, fitting
manufacturing, and fitting attachment to the hose by allowing the
fitting to be directly formed (molded), affixed, and sealed to the
hose assembly.
[0046] Additionally, the coupling 20 can be any other well known
type of the coupling known to those skilled in the art.
[0047] Throughout this application various publications are
referenced by citation or number. Full citations for the
publication are listed below. The disclosure of these publications
in their entireties are hereby incorporated by reference into this
application in order to more fully describe the state of the art to
which this invention pertains.
[0048] The invention has been described in an illustrative manner,
and it is to be understood the terminology used is intended to be
in the nature of description rather than of limitation.
[0049] Obviously, many modifications and variations of the present
invention are possible in light of the above teachings. Therefore,
it is to be understood that within the scope of the appended
claims, reference numerals are merely for convenience and are not
to be in any way limiting, the invention may be practiced otherwise
than as specifically described.
* * * * *