Note: Descriptions are shown in the official language in which they were submitted.
CA 02309857 2000-OS-11
Protactiva sheath
The invention relates to a protective sheath, in
particular for silencing rattling noises for cables, in
particular for cable harnesses, lines, braids, outer
tubes and the like, for example in motor vehicles, as
claimed in the preamble of claim 1.
Cables, lines, casing tubes and the like which are laid
in vehicles or systems can produce so-called rattling
noises due the vibration that normally occurs in
vehicles or in systems and machines. Furthermore, there
is a risk of the vibration rubbing away or chafing the
cable insulation or line or tube casing due to
vibration movements and relative movements, in
particular, for example against sheet-metal edges in
vehicles. Such problems occur, for example, not only in
landcraft and watercraft but also in aircraft as well
as in industrial systems or in machine construction.
(The word "cable harness" is frequently used in the
following text for such elongated objects to be
protected, without the invention being limited in
consequence).
In order to avoid rattling noises, sheaths are known
which are composed of polyurethane foam strips with a
smooth polyurethane skin on the outside and a flat
adhesive coating on the inside. The cable harnesses to
be sheathed are bonded onto one half of the inside of
the foam strip, the other half of the polyurethane foam
strip is then looped around this, and is adhesively
bonded in subareas both to cables in the cable harness
and to one half of the foam strip. This results in the
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flat flexible tubular element with a relatively smooth
polyurethane outer skin. Such sheaths can admittedly be
produced easily, but they are difficult to process.
They therefore have disadvantages in practical use. On
the one hand, a flat and relatively wide flexible tube
structure is produced, which results in difficulties
when being laid around corners and through narrow
apertures in a vehicle. Furthermore, the polyurethane
outer skin does not adequately withstand a chafing or
friction load; particularly in motor vehicles, it is
destroyed prematurely by contact with sharp sheet-metal
edges, so that the rattling and chafing protection is
lost. Furthermore, a disadvantage of the use of
polyurethane foam material is that it produces toxic
gases, for example cyanide, in the event of a fire.
In addition, protective sheaths for electrical cable
harnesses in the form of corrugated tubes are known,
with the corrugated tubes being composed of hard, solid
plastics. Such corrugated tubes are slotted over their
entire length, so that the cables can be inserted
individually through the slot. In order to prevent the ,
hard plastic corrugated tube producing rattling noises,
it is surrounded by felt strips, with the longitudinal
edges of the felt strips likewise being inserted into
the longitudinal slot for fixing purposes. In this
case, it is disadvantageous that a high labor penalty
is incurred in inserting the cables and felt strip
edges into a longitudinal slot in the corrugated tube.
Furthermore, there is a risk of the felt edges sliding
out of the longitudinal slot again when vibration
occurs, so that the composite assembly, and thus the
protection, is lost. Furthermore, the cables are not
fixed in the corrugated tube, so that noise can
likewise result.
DE 295 10 907 Ul discloses a protective sheath for
cable harnesses, which has a felt or foam strip whose
interior is coated with adhesive, with the width of the
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felt or foam strip being matched to the circumference
of the cable harness. A wear-resistant material web is
attached to the outside of the felt or foam strip and
is offset laterally with respect to the longitudinal
extent of the felt or foam strip such that it projects
beyond the felt or foam strip on one longitudinal side,
while an area of the felt or foam strip remains free on
the opposite longitudinal edge. After being bonded onto
the object to be protected, the felt or foam strip is
shaped into a flexible tube with the projection of the
material web being bonded such that it overlaps the
abutment area of the felt or foam flexible tube, and
thus closes the longitudinal edge. The material web
should preferably be formed from a polyester nonwoven,
with the material web being connected to the felt or
foam strip by adhesive bonding, needle-punching or
sewing over part of the area or over the entire area.
The adhesive on the projection of the material web, by
means of which the overlap of the felt or foam flexible
tube section is intended to be closed, should be a
self-adhesive which is covered by a protective paper.
Polyurethane foam, polyethene foam or cellular rubber
d
should be used as the material for the foam strip.
A disadvantage of this known sheath is that the foam
strip or the felt strip must be matched to the diameter
of the elongated objects, for example cable harnesses,
to be protected, so as to ensure the overlap of the
foam edges. Exactly matched sheaths of different
dimensions must therefore be provided for different
diameters. Another disadvantage is that the foam strip
is relatively stiff and, in the tubular form, produces
a relatively large restoring force in the outward
direction, which exerts a correspondingly high stress
on the overlap closure. Particularly in the case of
relatively high ambient temperatures and with narrow
radii, there is a risk of the sheath opening up, so
that the protection is lost. Furthermore, another
disadvantage in this case is that temperature
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influences result in toxic gases being produced.
Furthermore, the element is relatively thick and stiff,
so that laying is adversely affected. In addition,
pulling off the protective paper involves considerable
effort and also results in disposal problems, since
silicone paper is hazardous waste. Furthermore, fitting
is extremely difficult, particularly with relatively
long sections. If the adhesive strip is damaged while
being fitted, it no longer provides the adhesion force.
DE 297 11 387 U1 discloses a sheath for elongated
objects which can be used for objects to be sheathed of
different diameters. This sheath has an internal foam
strip and an external fabric web which is firmly
connected to the foam strip and projects beyond the
foam strip on both sides along the longitudinal edges
of said foam strip, with both projecting strips having
an adhesive coating on the inside of the projecting
fabric edge. This adhesive coating is covered by a
protective paper. The fabric web is a loop fabric which
will not be described in- any more detail, with the
loops being formed as adhesive or hooking partners for ,
the hooking members of a hook support element, so that
the sheath can be detachably connected to the hook
support element like a Velcro-type fastener. In order
to attach the sheath to, for example, a cable harness,
a projecting fabric edge of the sheath is placed
against a cable harness to be sheathed, and is pushed
against the cable harness. The sheath is then wound
around the cable harness until the entire width of the
foam strip surrounds, and if required overlaps, the
cable. That fabric edge which projects further and is
provided with adhesive is then pressed against the
outside of the fabric web that has already been laid on
the cable harness.
A disadvantage of this known sheath is that protective
paper must first of all be removed from adhesive
surfaces. In addition, the sheath must be bonded to the
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cable along the longitudinal edge of the sheath, and
then laid transversely around the cable, across the
longitudinal extent. For long cable harnesses, this
work is difficult since the object is to produce a
uniform contact pressure at all points on the cable
harness. The sheath must be pulled tight for adhesive
bonding over the entire length, and this can not always
be done correctly. Furthermore, a general disadvantage
of foam materials is that these foam materials
withstand chafing or friction loads relatively poorly.
The obj ect of the invention is to provide a protective
sheath, in particular for cables, cable harnesses,
lines and the like, which effectively silences rattling
noises, is easy to fit and, in particular, has good
resistance to wear and abrasion.
This object is achieved by a protective sheath having
the features of claim 1. Advantageous developments of
the invention are described in the dependent claims.
According to the invention, the protective sheath is in
the form of a wound strip having an essentially two-
layer structure with two textile layers, in which case
the wound strip has an inner textile layer, with
respect to the object to be protected, composed of a
nonwoven, and an outer textile layer, with respect to
the object to be protected, composed of a warp-knitted
velour. The two textile layers are connected to one
another by adhesive bonding, with the adhesive
preferably being applied in subareas, for example in
the form of a nonwoven or film which can be activated
by heat. Both textile layers are produced from
synthetic fibers, in particular polyamide or polyester,
with the nonwoven preferably being a needle-punched
nonwoven. The outer textile layer, in the form of a
warp-knitted velour, is preferably a two-bar warp-
knitted velour material with a knitted back warp and a
front warp which is knitted into the back warp, with
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the front warp forming roughened-up velour loops which
project outward from the material or textile layer.
Such roughened-up looped velour materials are known as
the mating elements for so-called mushroom strips, for
use as Velcro-type strips. According to the invention,
the roughened-up velour loops are, however, formed with
abnormal height.
The protective sheath according to the invention is
wound in a helical shape from a roll onto the object to
be protected, with the inside of the protective sheath,
which is covered with an adhesive layer over its entire
area, being pulled tightly onto the object to be
protected. In this case, the turns are wound with a
slight overlap. According to the invention, the
adhesive and the velour loop structure are placed
against one another in such a way that neither the
adhesive layer nor the velour loops are affected in any
negative way during the process of unrolling from the
roll. Furthermore, the adhesion force of the adhesive
is matched to the adhesive bonding between the textile
layers in such a way that the unrolling force from the ,
roll is less than the force required to separate the
two textile layers from one another.
Unrolling from a roll and helical winding onto a cable
harness considerably simplify the fitting process.
Furthermore, there are no protective papers. In
addition, it has surprisingly been found that the
specific arrangement and configuration of the textile
layers, namely an inner nonwoven layer, in particular a
needle-punched nonwoven layer, and a warp-knitted
velour layer arranged on it, for example with adhesive
bonding in subareas, in particular a thermoplastic
nonwoven adhesive bonding, achieves a wear resistance
which until now has not been provided by any comparable
protective sheath. The wear resistance of the overall
composite material is even considerably better than the
wear resistance of the individual layers. The composite
CA 02309857 2000-OS-11
material makes it possible to compensate for movements
which could not be coped with by one of the layers on
its own. The sheath according to the invention may be
relatively thin, for example only 1.5 to 4 mm thick. It
is particularly advantageous to treat the textile
layers, for example to coat them, with a means that has
been made hydrophobic. This measure increases the wear
resistance and stabilizes the loops, which have been
raised to more than the normal extent.
The invention will be explained in more detail in the
following text using, by way of example, a drawing, in
which:
Figure 1 shows a cross section through a protective
sheath according to the invention;
Figure 2 shows a protective sheath as shown in Figure
1, with a three-layer adhesive layer;
Figure 3 shows a schematic plan view of the thread
profile of a warp-knitted velour layer.
A protective sheath 1 according to the invention
(Figure 1) has a textile fabric or textile layer 2
composed of a nonwoven on the obj ect side with respect
to the object to be protected, a textile fabric or
textile layer 3 composed of a warp-knitted velour
facing away from the object and arranged on said layer
2, and an adhesive bonding 4 arranged between the
layers 2 and 3 and connecting them to one another. On
the object side, the layer 2 has an adhesive bonding
layer 5 over the entire surface.
The term nonwoven materials means flexible, porous
fabrics which are not produced by the classical method
of weaving a warp and weft or by knitting, but by
solidification of fiber nonwovens. Fiber nonwovens are
relatively loose materials composed of natural,
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synthetic, organic or mineral textile fibers, which are
in general held together by the natural adhesion of the
fibers. In this case, the individual fibers may have a
preferred direction, or may be in random directions, as
so-called random-laid fiber nonwovens. Such nonwovens
may be solidified adhesively, for example by adhesive
bonding or welding of the fibers or mechanically, for
example by needle punching or by the influence of heat
or chemicals. Needle-punched nonwovens are preferably
used according to the invention since, in comparison
with the other solidified nonwovens, these have a
particularly high affinity to the velour layer.
The term knitted materials means materials which are
formed by a method, similar to knitting, for producing
expandable textile fabrics which are composed of thread
loops connected in the form of shanks.
The outer layer 3 (Figure 3 ) is a two-bar warp-knitted
velour. As the material base, the first bar or back
warp 9 is formed by knitting from a synthetic filament
with a closed tricot weave. The filament 10 which forms
a
the back warp 9 is preferably a multifilament, that is
to say each thread is formed from a plurality of
individual threads, for example 5 to 20, and in
particular 8 to 12 individual threads. Polyamide or
polyester is preferably used as the yarn or thread
material. The fineness of the filaments used for the
first bar or back warp is between 30 and 80, and in
particular between 40 and 50 dtex (dtex - 0.1 tex; 1
tex - 1 g/km filament length). For example, the yarn
with the classification dtex 44 F10PA is used, that is
to say a yarn with dtex 44, which is formed from 10
polyamide individual fibers.
The second bar of the warp-knitted velour or front warp
11 is likewise formed from a synthetic filament 12,
with the second bar 11 being formed as a so-called
closed velour. This type of knitting results in the
CA 02309857 2000-OS-11
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formation of loops 13 which extend, projecting from the
surface, transversely or at right angles to the
intended surface of the material base 9, with the loops
13 of the second bar 11 being woven into the first bar
9. The material for the filaments 12 of the second bar
11, or to form the velour loops 13, is a polyamide or a
polyester, with polyamide being preferred.
The filament is preferably a multifilament having a
fineness of 60 to 90 dtex, in particular 70 to 80 dtex,
with 5 to 20, in particular 8 to 12, individual fibers
per filament, for example a filament with the
classification dtex 78 F10 or dtex 76F9. The loop
height of the loops 13 of the second bar 11 is,
according to the invention, between 0.9 and 1.3 mm,
with the number of loops 13 being between 3400 and
3600 cm2.
The mass per unit area of the two-bar warp-knitted
velour is preferably between 100 and 250 g/mz, in
particular between 160 and 220 g/m2, with the overall
thickness of the warp-knitted velour being, for
example, between 1.05 mm and 1.4 mm. The back warp and
the front warp may be manufactured from filaments of
different colors; for example, the front warp may be
black, and the back warp may be configured from warning
colors or bright colors such as yellow or orange. The
velour loops 13 of the second bar 11 are roughened up
by means of a roughening process, that is to say they
are aligned transversely with respect to the plane of
the first bar 9, and are expediently thermofixed. In
the thermofixing process, the roughened knitted
material is subjected to hot air between 165 and 190°C,
as a result of which a material is produced whose loops
deform when pressure is applied, but align themselves
once again, after a certain waiting or recovery time,
when the load is removed. Loops 13 of such a
configuration in the second bar 11 are known for use as
a Velcro-type strip, although the loops of the warp-
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knitted velour used according to the invention project
higher, in particular 10~ to 40~ higher, than the loops
of known Velcro-type strips. This is thus a new
product, which has been created for the purposes of the
invention.
The first textile layer 2, or the inner layer 2, is a
fiber nonwoven composed of synthetic fibers. This
nonwoven is preferably a needle-punched nonwoven, which
ensures excellent compatibility with velour. A
thermally or chemically bonded nonwoven may, however,
likewise be used. Synthetic fibers, in particular
polyamide and/or polyester, are preferably used as the
material for the nonwoven fibers. The mass per unit
area of the nonwoven is expediently 40 to 200 g/m2, in
particular 80 to 120 g/m2, with a preferred thickness of
between 1 and 3.5 mm, in particular between 1.5 and
2.5 mm.
Both textile layers may be made hydrophobic or may be
formed from fibers or filaments that have been made
hydrophobic. In particular, the fibers may have a
coating, which is known per se, composed of
polytetrafluoroethene, which makes the fiber surface
particularly smooth and nonpolar.
The two textile layers 2, 3 are laminated with an
adhesive or an adhesive layer 4 arranged between them
to form a laminate. The adhesive layer 4 is located
between one surface of the nonwoven 2 and the first
guide bar 9 of the warp-knitted velour material 3, so
that the loops 13 of the velour material 3 are arranged
such that they face away from, or point outward away
from, the nonwoven layer 2. The adhesive or the
adhesive layer 4 may be composed of spray adhesive, an
adhesive film, a scattered adhesive such as powder, an
adhesive paste or a staple fiber adhesive network. It
is preferable for the adhesive bond not to be applied
over the entire area between the layers, but to leave
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areas between the two textile layers unbonded. This can
be done, for example, by using an adhesive film with
holes stamped in it or by scattered adhesives such as
powder, with the surface to be covered with powder or
to be scattered on being covered by a mask, for example
a perforated mask. Once the perforated mask has been
removed, this results in a grid pattern with powdered
and unpowdered areas. Furthermore, adhesive paste can
be applied in droplets, or can be applied in any other
way that produces a pattern, for example a pattern of
dots. When using a staple fiber adhesive nonwoven or a
fine, thin staple fiber adhesive network, the wide gaps
in the structure of the staple fiber adhesive network
ensure that there are unbonded areas between the
textile layers. The adhesive bonding process is
preferably carried out using thermoplastic adhesives
which can be activated by heat, in which case the
adhesive may have a temperature-dependent viscosity
which allows adequate flexibility or elasticity. The
adhesive should be applied such that the adhesive can
penetrate into the textile layers in the area of the
adhesive bonds, in order to be anchored there. The
1
adhesive may need to be adapted for use in vehicle
construction, and in particular it must retain its
strength at temperatures up to, for example, 105°C, as
well. During the process of anchoring the adhesive in
the textile layers, penetration into the textile layers
should be ensured, but the adhesive should only
adhesively bond the warp-knitted velour to the first
bar 9, or anchor it in the first bar 9.
A staple fiber nonwoven adhesive, that is to say a thin
network-like nonwoven composed of thermoplastic
adhesive fibers with a mass per unit area of, for
example, 5 to 40 g/m2, in particular 10 to 30 g/m2 and
preferably 12 to 22 g/m2, is preferably used.
The layers are laminated under pressure while the
adhesive is thermally activated at the same time, so
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that the adhesive can penetrate into both textile
structures, ensuring that it is anchored there, in
particular after the temperature drops.
Another adhesive layer 5 is applied to the surface of
the needle-punched nonwoven 2 on the object side, which
faces away from the layer 3, and is used to produce an
adhesive bond to the object to be protected. This
adhesive layer 5 is in the form of a contact adhesive.
When used as a wound strip delivered in the rolled-up
state, the contact adhesive must be such that it is
held on the needle-punched nonwoven and can be
separated from the velour loops. To this extent, it
must be well anchored in the needle-punched nonwoven
since, otherwise, when unrolled from the roll, the
adhesive would become detached from the lower face of
the protective sheath, facing the object to be
protected. This could be achieved, for example, by the
adhesive being applied to the needle-punched nonwoven
layer under temperature and pressure, and by the strip
subsequently being rolled with relatively low tension
so that the anchoring produced between the adhesive and
the velour loops is as poorly adhesive as possible.
According to one special embodiment of the invention,
the adhesive layer 5 has three layers (Figure 2) and is
provided with a first adhesive layer 16 facing the
needle-punched nonwoven, a thin adhesive layer base
film 17 and a second adhesive layer 18 which is
arranged on the base film 17, opposite the layer 16.
The adhesive layers 16, 18 are in this case preferably
provided with different viscosities, with the adhesive
layer 16 having a relatively low viscosity, very good
adhesion and the capability to penetrate relatively
well into the nonwoven. The adhesive layer 18 has a
different viscosity which makes it possible, when the
protective sheath strip is in the rolled-up state, for
the adhesion to the velour loops to be only sufficient
for the roll to remain in the rolled-up state and not
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to unroll itself on its own. The sheath strip can thus
be pulled off the roll without the adhesive layer 16
being pulled off the needle-punched nonwoven while, on
the other hand, ensuring adequate adhesion to the
object to be protected.
Furthermore, the adhesion behavior of the adhesive
layer 18 is matched to the adhesion force of the
adhesive layer 4 between the textile layers 2, 3. The
force required to unroll the strip from the roll is
less than the adhesion force or separating force which
is required to separate the two layers 2, 3. This
prevents the layers 2, 3 from being separated from one
another, or delaminated, due to the adhesion force of
the adhesive layer 4 being exceeded during the
unrolling process. It has been found to be advantageous
if the unrolling force, resulting from the adhesion
capability of the adhesive layer 18, is only half as
great as the separating force which must be overcome in
order to separate the layers 2, 3 from one another in
the region of the adhesive bond 4. The adhesive layer 5
and the layers 16, 18 are preferably formed from
acrylic adhesive, with different adhesives expediently
being used for the layers 16, 18 when a three-layer
adhesive layer is used.
The rolled-up protective sheath strip according to the
invention and formed in such a way is pulled off the
roll and is placed with the adhesive layer 18 on the
object to be protected, the winding process is then
carried out, with the winding then being carried out
helically around the object to be protected, obliquely
with respect to the direction in which the object
extends, and with a superimposition, that is to say an
overlap, of the protective sheath preferably being
provided. At the end of the winding process, a final
winding is expediently carried out with an adhesive
strip, thus preventing the winding from being opened.
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If a chafing load is applied to the protective sheath,
alternate tensile and compression loads are applied to
the projecting velour loops of the warp-knitted velour
material. These tensile and compression loads are
passed on into the back warp, with the introduction of
the force into the back warp and into the adjacent
filaments of the front warp, which form the loops,
being superimposed. The knitted back warp can flex and
deform in response to stress due to its flexible
structure, with energy being dissipated by friction
between the filaments.
In addition, shear forces which are not dissipated just
in the warp-knitted velour layer are introduced via the
adhesion points into the nonwoven layer arranged
underneath the warp-knitted velour.
In addition to the characteristics of the textile
layers, the adhesive bonding between the two layers is
likewise limited, in that stress in the laminate can be
dissipated by plastically elastic deformation.
This specific configuration of the textiles which form
the laminate means that stresses are dissipated or even
do not occur at all. When a tensile load is applied,
the laminate probably lengthens step by step in four
stages, with each lengthening step on the one hand
causing friction and on the other hand distributing the
force or stress which acts - in the extreme case - on a
velour loop in a pyramid-stepped fashion into the
nonwoven. Stresses which exceed the tearing strength of
the filaments are avoided.
The step-by-step lengthening or the step-by-step
pyramid stress introduction takes place in such a way
that a tensile force is applied to a velour loop in the
first stage. The velour loop is flexed by elastic
deformation, that is to say with lengthening. This also
results in a tensile force being introduced into the
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adjacent velour loops which are formed by the same
filament and which, in the extreme case, are drawn
toward the velour loop to which the force is applied.
In the area in which the velour loop is woven into the
back warp, or the velour loops are woven in, the
movement produced in response to the tensile force
leads on the one hand to gathering of the filament
curved shape in the velour loop in the back warp, and
on the other hand to friction between the velour loop
filament and the back warp filament. If the stress
cannot be dissipated just by the mechanical reaction of
the tension-loaded velour loop, its immediate neighbors
and the anchoring of the individual velour loop in the
back warp, the stress is introduced into the next
stage, in that the force acting on a velour loop is
passed on via the two loop curves, by means of which
the velour loop is woven into the back warp, to a
number of loops and filaments in the back warp.
Owing to the large number of contact points or loops of
filaments in the back warp, the stress introduced at
two points is distributed over a large area, with the
large number of loops each absorbing only a fraction of
the introduced stress, and with the area surrounding
the points at which the force is introduced flexing
elastically.
The friction can dissipate the energy in the material,
with the force introduction area, that is to say the
area in which the fibers can be shifted with respect to
one another, being enlarged due to the material being
made hydrophobic and due to the fibers sliding better
on one another in consequence, so that the dissipation
of energy thus also takes place in a manner that causes
less damage to the individual fibers. The hydrophobic
treatment thus results in the material distortion which
is produced being distributed over a larger area.
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The material distortion which is produced in the warp-
knitted velour layer, in particular in the lower bar,
necessarily also results in any tensile force or stress
being introduced into the nonwoven layer via the
adhesion points arranged in the distortion area being
distributed over a large area, in the nonwoven layer,
for its part, reacting by predominantly elastic
distortion, and with the stress which acts on points
where the adhesive is applied in the nonwoven acting
directly on a large number of filaments in the nonwoven
layer and, as a result of friction between the
filaments, indirectly on an even greater number of
filaments in the nonwoven layer. As a result of the
fact that the force is distributed over a very large
area in the back warp, the stress that occurs is
applied to a large number of adhesion points, so that
the adhesion points are not overloaded.
The construction of the laminate from two specific
textile layers and adhesion points which are arranged
between them and are preferably in subareas results in
a high stress introduced in a small area being
distributed over an area which becomes ever larger from
layer to layer, with stress and energy largely being
dissipated in particular by means of spot bonding of
the second textile layer.
The materials used are matched to the conditions that
occur in use. To this extent, textiles and adhesives
are chosen which are not sensitive to the softeners
used, for example, in the cable insulation, and which
may be released. When used in the field of hydraulic
systems, the materials used are resistant to hydraulic
fluid. Furthermore, the adhesives retain their
characteristics, without any significant limitation,
over a wide temperature range, for example from -30°C
to +110°C. Furthermore, when used in vehicles of any
type, materials are expediently resistant to oils,
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greases and, as far as possible, to solvents, and are
also resistant to the normal media used in vehicles.
When sheathing safety-relevant objects, it may be
advantageous to design the outer layer, that is to say
the warp-knitted velour, using a color specified for
this object, or using a conventional warning or bright
color.
The fire characteristics of the entire sheathing
material expediently comply with the technical
regulations of the vehicle manufacturers.
In the case of the protective sheath according to the
invention, it is advantageous that this sheath can be
fitted in a particularly simple and reliable manner,
with the construction of the protective sheath laminate
according to the invention resulting, surprisingly, in
novel, very good wear protection. Furthermore, the
configuration of the protective sheath laminate
according to the invention ensures excellent silencing,
in particular due to the loop structure and the loop a
height. In addition, it is advantageous that the
protective sheath can be arranged in a vehicle in a
manner known per se by means of a Velcro-type strip or
a mushroom strip, thus also in this way making it
possible to take account of the requirements for simple
fitting.
The protective sheath material according to the
invention is preferably stored on a roll in the form of
a wound strip, and the strip is wound helically around
the object to be protected. If required, the protective
sheath may also and with equally good success be laid
longitudinally, forming a flexible tube, around the
object to be protected. The protective sheath according
to the invention may be used not only in motor vehicles
but also in watercraft and aircraft. However, it may
also be used in machine or plant construction, in
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particular in areas which are subject to vibration
loads, in particular for generators, compressors,
turbines etc. In this case, use is not limited to
electrical cables, lines or cable harnesses. Fuel
pipes, hydraulic lines and the like may also be
sheathed to provide chafing protection and to
counteract the production of noise. Furthermore, the
protective sheath according to the invention may be
used in vehicle construction wherever interior parts,
for example dashboards, strut linings and the like,
which can rub against one another or rattle, are
intended to be provided with rattling protection
arranged in between them. In this case, the protective
sheath may be arranged not only between plastic parts
but also between plastic parts and metallic bodywork
parts. The material according to the invention is also
distinguished by excellent pliability.
The essential feature is that it has become known that
it is not sufficient, according to the prior art, to
design the outside to be as hard and wear-resistant as
possible to make it possible to withstand chafing
forces. In fact, the essential feature is to equip the
outside with a flexible and, in places, elastic loop
structure that is relatively soft, and to provide a
nonwoven material on the object side. This combination
of selected flat textiles results in optimum protection
effects against the action of chafing, and optimum
silencing and noise attenuation. The known materials or
material combinations ensure either good chafing
protection and inadequate silencing and/or noise
attentuation, or vice versa.
