Note: Descriptions are shown in the official language in which they were submitted.
L7'~6
BACKGROUND
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This in~ention is directed to a reinforced and
insulated flexible hose made with elastic materials and
flexib~e reinforcement strands, together with the
apparatus and method for making the hose.
Pr~or technology consists of two known methods
of insulating hoses. Each of these methods appl~ a
sponge or foam mater~al by a seconaary operation. In
the first prior method, a hose having any type of con-
struction or material is selected for the insulation
application. A foam or sponge tubular extrusion is
produced with the inside diameter slightly larger than
the outside diameter of the hose. ~his extrusion is
slid over the hose~ Generally, no adhesive is applied
to the outs~de of t~e hose. T~e disadvantages of this
construction include the fact-that this method of manu-
facture is only successful with short lengths, generally
under about 12 feet in length, depending on the sizes,
materials and clearances. Of course, it is dificult
to slide the foam extrustion over the hose, and this
results in high labor costs due to the assembly time.
With the resulting two-piece construction, there is no
adhesion between the insulation and the hose, a~d this
results in a structure which is more difficult to package
and wit~ a ~eight disadvantaga due to the method of
c~nstructiOn. Generally, the hose is purchased from one
source; and the extruded outer tubular insulation layer
from another, to result in a difficult problem in achie~ing
the size tolerances which permit ~ractical assembly.
The second prior art method utili~es a flat,
precut width and length of an extruded or molded flat,
flexible foam or spon~e insulation material. This
material is wrapped around a previsouly extruded~ flexible
hose. A longitudlnal butt or lap seam is adhesively
bonded to complete the hose assembly. The disadvantages
of this type of consiruction includes the fact that no
adhesion of the insulation material to the hose is achieved.
~nother disadvantage is the jolnt of the porous insulation
10 material ~ith its adhesive joint, because such joints are
difficult to form in a secure fashion. Generally, this
method is used to cover only short lengths o~ hose, possibly
due to the high cost of labor in connection with the insula-
tion materlal layer application and adhesive joining. Manu-
facturerers of such hoses usually buy the hose and insula-
tIon material from different sources, with the result of
more difficult coordination and assembly. This often
res~ults in a we~ght disadvantage for this type of construc-
tion. It IS not commercially supplied in lengths over 50
20 feet,
Thus, there is a need for an eco~omic and secure
xeinforced insulated hose produced on a continuous basis
with wnitary construction without adhesive joints in
the insulation layer. Furthermore, it is desirable to
have a long hose so that long runs can be made with such
an insulated hose without hose connectlon.
SU~ARY
In order to-aid in the understanding o~ -this
in~ention, it can be stated in essentially sum~ary form
that it is directed to a reinforced and insulated hose
and apparatus and method therefor, with the hose comprising
a continuously extruded, flexible hose liner with a flex-
ible strand-type reinorcement thereon which leaves access
to a ~ortion o~ the outer surace o~ the hose liner, and
a continuously e~truded flexible foam cover layer thereon
which is bonded through to the liner surface so that a
locontinuously extruded reinforced and insulated hose is
pFoduced.
It is thus an object of this invention to provide
a reinforced and insulated hose which is of bonded and
continuously produced construction so that long, indefinite
lengths can be manu~actured. It is another object to
pro~ide a reinforced insulated flexible hose wherein a
flexible liner is reinforced and is covered with an insula-
tor layer. It is a ~urther object to provide a ~lexible
hose construction which is reinforced and insula-ted and
wherein each of the layers is structurally bonded together,
20 but without the use of seams so that a ~tructure o~ long
liEe is achieved. It is another object to provide a
method whereby such a reinorced and insulated flexible
hose cons~.ruction can be produced. It is a Eurt~ler object
to provide an extruder apparatus where entrained air can
be introduced into rubberlike materials duriny the extru-
sion proces.s to result in a continuously extruded Eoamed
insulated layer on the hose. It is another object to add
chemical blowing agents to the plastic or ru~berlike com-
pound prlor to extrusion and vulcanization process to result
30 in continuousl~ extruded ~oamed insulated layer on the hose.
Accordingly, one aspect o.~ the invention provides a
reinforced insulated flexible hose comprisi:ng:
a continuous flexible hose liner layer made of elastomeric
material;
a reinforcement layer on said liner layer, said reinforce-
ment layer comprising at least one strand of flexible material
on the outer surface of said hose l~ner layer to a;d constraint
of said hose liner layer agai.nst expansion ~y internal pressure;
and
an insulati.on layer over said rein~orcement layer and said
hose l~ner layer, with sai~d insulation layer being attached at
least to said hose liner layer through openings in said reinforce-
ment layer, said insulation layex being made o~ elastomeric
material havi.ng yas~filled pores therein.
~ nother aspect of the invention provides the method
of making a reinforced and insulated flexible hose comprising
the steps of:
extruding a tubular h.ose liner of ~lexible material;
engaging a reinforcement layer of flexible reinforcement
0 strands around the hose liner; and
extruding a flexible insulation covering over the liner
layer and reinforcement layer.
B~IE~ DESCR.I:PTION OF THE DRAWINGS
FIGURE 1 is a side-elevational view of the preferred
embodiment of the apparatus by which the reinforced and insulated
Elexible hose o~ this invention is made and by which the method
steps in produciny it are achieved.
E'IGURE 2 is a side-elevational view of the hose, with
parts broken away and parts taken in section, as seen at point 2
in FIGURE 1.
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11~17 ~
FIGURE 3 is a side-elevational view of khe hose, with
parts broken away and parts taken in section, as seen at point 3
in FIGURE 1.
FIGURE 4 is a side-elevational vie~ of the hose, with
parts broken a~ay and parts taken in section, as seen at point 4
in FIGURE 1.
FIGURE 5 is a si:de-elevational vïew of the finished
hose with parts broken away and parts taken in section, as seen
at poi,nt 5 in FIGURE 1.
FIGURE 6 is a side-elevational vie~ of another
preferred embodiment of the apparatus by which the reinforced
and insulated hose of this invention is produced and the method
achieved.
-5a-
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FIGURE 7 is a side-elevational view, with paxts
borken away and parts taken in section, of the ram air
device, extruder and crosshead die which produces the
foam insulation on the ~ose of this invention.
FIGURE 8 is a side-elevational view, with parts
broken away and parts taken in section, of a first pre-
ferred embodiment of the reinforced and insulated hose
of this invention.
FIGURE 9 is a side-elevational view, with parts
lO broken away and parts taken in section, of a second pre-
ferred em~odiment of the reinfoxced and insulated hose
of this invention.
FIGURE 10 is a side-elevational view, with parts
broken away and parts taken in section, of a third pre-
ferred embodiment of the reinforced and insulated flexible
hose of this invention.
FIGURE 11 is a side-elevational view, with parts
broken àway and parts taken in section of a fourth pre-
ferred e~bodiment of the reinforced and insulated hose
20 o~ this invention.
DESCRIPTION OF TXE PREFERRED EMBODIMENT
FIGURE 8 shows the first preferred embodiment of
the reinforced and insulated flexible hose of this inven-
tion. The hose is ~e~erally indicated at 10 therein.
Hose 10 comprises hose liner 12, re~nforcement 14 thereon,
and foamed or sponge layer 16 which forms the insulation
layer and outer layer of hose 10. Reinforcement 14 is
formed as a plain pattern tubular continuous knit reinforce-
ment layer, with an open space of about 3/32" in the
knitting. The open space through the kni-tted fabric rein-
forcement layer is so that the outer foam/spange layer
16 can directly attach to the outer surface of hose liner 12.
.
Hose 20, shown in FIGURE 9, is the second preferred
embodiment of t~e re~nforced and lnsulated flexible hose
of this Ln~entlon. It has the same hose liner 12, but th~
reinforcement 22 thereon is a braided reinforcement with
an open space. Preferably, it has an approximately 1~8
inch diamond brai~d pattern as a re~nforcement structure.
The open space between the strands of the open braid pro-
vide for direct attachment between the outer foam/s~onge
layer 16 and the hose liner.
FIGURE 10 illustrates hose 24 as the third pre-
ferred embodiment of the reinforced and insulated flexible
hose of this invention. Hose 24 has the same hose liner 12,
but it is wrapped with spiral reinforcement 26. The spiral
rei.nforcement 26 is a plurality of strands helically wrapped
in the same direction. The number of strands is such that
the strands are approxima~ely at a 54 degree angle with
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respect to the axis of the hose and are spaced approxi-
matelv 1/8 inch apart. Again, this space provides for
attachment through of the foam/sponge layer 16 through
the spiral reinforcement layer to the hose liner 12.
Hose 28 is the fourth preferred embodiment of
the reinforced and insulated flexible hose of ~his inven-
tion. It comprises hose l ner 12 which is wrapped with
spiral reinforcement layer 30. Spiral reinforaement
layer 30 is double-ply reinforcement with a plurality
of strands helically wrapped around hose liner 12 ln each
direction. The spiral angle of both wraps is about 54
degrees with respect to the longitudinal axis of the hose,
and there are enough strands layered in each direction
so that the strands are spaced approximately 1/8 inch
apart. This space provides for attachment of the insula-
tion layex 16 to the liner layer 12.
Attachment of the foam/sponge layer 16 through
the reinforcement layer and through the reinforcement layer
to hose liner 12 is enhanced by application of a proper
agent for such purpose. These agents may be called
~Iprimers~ although they may have adhesive or;other attach-
ment enhancing properties. Depending on the material of
the hose liner 12 and the foam/sponge layer 16, they can
be selected from the followlng group: Chemlock 607 is an
adhesi~e for siLicone rubber and specialty elastomers.
It is made by Hughson Chemicals ~ivision of Lord Corpora-
tion, Erie, PA 16512. Also included in this group is
isocyanate and surface active chemicals such as xylene,
hexine, BCA, cyclohexanone. Also in this group are other
adhesives suitable for the combination of materials.
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Hose liner 12 and foam/spon~e layer 16 can be
selected from the same group. This group has the sub-
groups of elastomers and flexible synthetic p~lymer
composition materials. The elastomer subgroup includes
silicone rubber, EPDM, CPE, ethylene acrylic, neoprene,
nitrile, epochlorohydrin, Viton, and other synthetic
~`
-~ and organic rubberlike compounds. The flexible synthetic
polymer composition mater~al subgroup inclu~es polyvinyl
chloride, EVA, polyethylene, Halar, FEP, Kynar, and other
similar materials.
The reinforcement strands 14, 22, 26, and 30 are
selected from the group including Nomex, Kevlar, Dacron
nylon, Xayon, and fi~reglass.
Referring to ~IGURE 1, the line of apparatus
generally indicated at 32 produces the reinforced and
insulated ~lexIble hose of this invention. Extruder
34 is the number one extruder along the process line.
It is prefera~ly a conventional crosshead extruder to
whlch the material for hose liner 12 is applied. The
20 elastomer is mi~ or strip-fed into the extruder. The
elastomer is carried to the crosshead die where the hose
liner 12 is extruded on a continuous basis. ~ir i5
app:Lied to the inside of hose liner 12, thereby in~lating
llner ].2 and preventing its collapse or kinking. After
the extruded hose liner 12 exits from the die, it passes
through curing cham~er 36 where it is vulcanized or therm-
ally stabilized.
radetnarl~5
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Reinorcement-applying machine 38 is a knitter
to produce hose 10, a braider to produce hose 20, or a
spiral winder to produce hoses 24 or 28. Photocell loop
height detectors 40 and 42 are positioned at the input
and output of re~nforcement-applying machine 38 so that
feed rates of t~e various machines can be matched to
prevent unbalanced feeding from machine to machine along
the prod~ction apparatus 32~ The output of reinforcement
applying machlne 38 is reinforced hose 44 shown in
10 ~IGURE 3,
Primer or surface conditioner is applied to the
reinforced hose 44 ~y primer sprayer ~6. A fine spray
mist of the primer is applied to the exterior surface
of the reinforced extruded liner 44. Next, the liner
passes through preheater 48 before the next stepO This
preheater removes solvents from the primer and heats
- the reinforced hose 44 to a proper temperature to
insure proper adhesion and preventing the extruder
foam/sponge layer (16) from blowing away from the liner
2~ (44) during vulcanization.
Extruder S0 receives the reinforced hose liner
and extrudes layer 16 thereon. Extruder 50 i.s a cross-
head extruder with a suitable die so that the reinforced
hose liner enters the crosshead die of extruder 50, vacuum
i9 applled to the outer surface at the locati.on where the
layer 6a ls extruded thereon. This vacuum removes tr~p~ed
air ~etween the exterior of the reinforced hose and the
new layer 16 appl~ed thereto. The vacu~ permits close
contact between the newly extruded layer 16 and the outer
surface of the reinforced hose liner. In this way, the
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layer 16 engages through the openings in the reinforce-
ment layer and achieves an adhesive attachment through
the reinforcement to the liner 12. In this way, secur~-
attachment of layer 16 ts achieved.
T~e layer 16 contains a material which causes
it to expand into a foam or spon~e material. ~he foam
layer expansion is accomplished by the expansion of gas
~n the material. The gas bubble production in the
material can either be accomplished by addition of
chemical blowing agents or by entraining air or
other common gas injected by a ram air apparatus.
Entrainment will be discussed in more detail below.
Chemical blowing agents are thoroughly discussed in an
article "Chemical Blowin~ Agents," by B~ron A. Hunter,
published in Rubber Aqe, of February, L976, pages 19-25.
Addittonally an art.`cle called "A Selection Guide to
Blowing Agents for Structural Foam Molding" appeared in
Plastics Technolo~y, of March, 1976, at pages 31-36.
Both these articles dtscuss various chem~cal blowing
agents which may be incorporated in the layer 16 as it
is extruded onto the hose.
The product be:ing discharged from extruder 50 is
shown in PIGURE 4. ~his is the hose before the layer 16
is substantially expanded. The insulation layer 16 is
extruded to a thickness o~ approximately 0.1 to 0.125
inch in the unexpanded condi~ion. The structure is now
a covered liner in the condition shown in FIGURE 4.
From the extruder 50, the covered liner enters c~ring
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chamber 52. The temperature of the curing chamber is
set to activate the blowing agent or expand entrained
air in the cover compound to form the expanded foam/
sponge layer in the finished hose illustrated in
FIGURE 5. The temperature of the curing chamber 52
is sufficient to cause cross-linking or vulcanization
of the rubberlike compound after the expansion is
achieved. Thereupon, the structure is stabilized.
~akeup reel 54 receives the finished product. The
hose is thereafter cut to length and packaged.
FIGURE 6 illustrates process apparatus 56 which
is the same as process apparatus 32 except for the fact
that no primer sprayer 46 is employed and no preheater
48 is employed. In this arrangement, the outer condition
of the reinforced liner as it comes from reinforcement-
applying machine 38 is satisfactory to receive adhesive
attachment thereto by the insulation layer 16 as it is
applied by extruder 50. In that case, the materials are
sufficiently compatible that attachment of the insulation
layer to the liner layer, includin~ throuyh and/or to the
reinforcement layer, i5 achieved by the materials without
any special primer.
The preferred process employs extruder 60, illus-
trated in FIGURE 7~ as the extruder which applies the
covering 16 in the position of extruder 50 in FIGURES 1
and 6. The preferred process incorporates gas, including
gas mixtures such as air, into the milled stock. Extruder
60 is a fairly conventional crosshead extruder which has
the extruder gear box 62 driving extruder screw 64 in
extruder barrel 66. Crosshead die 68 receives the rein-
forced tubing rom one side through an inlet seal.
Interiorly of the inlet seal, there is a sealed vacuum
chamber followed by another seal, after which the cover
extrusion takes place. Thus, the sealed vacuum chamber
around-the reinforced tubing is directly adjacent to the
extrusion chamber so that a vacuum is drawn on the rein-
forced hose liner just before the extrusion of the cover
thereon. The basic extruder is conventional, except
that there are no air vents at the inlet end of the screw.
~he vacuum chamber is part of the process for producing
t~e reinforced and insulated hose.
Another novel~feature of extruder 60 relates to
the introduction of raw material into the extruder. Feed
chamber 68 is tubular and is open at the top and is
connected to the interior of barrel 66 at the bottom. Ram
70 fits into the feed chamber and closes the top thereof.
Ram 70 is raised and lowered by means air cvlinder 72
which has its piston rod connected to ram 70. Thus,
ram 70 can be raised out of the feed chamber for the intro-
duction of stock into the feed chamber, and the ram can
be brought down tc close the feed chamber and force the
stoc~ into barrel 66 to be advanced by screw 64. Feed
chamber 68 also has gas line 74 connected thereto~ Com-
pressed air is a convenient gas, although pressurized
nitrogen is also feasible. Gas is introduced into feed
chamber 63, and the gas is entrained into the feed stock
as the feed stoc~ is milled by extruder screw 62~ ~lith
the positive stock feed accomplished by ram 70 and with
the incxeasing pressure alon~ with extruder screw 64, ,~
the gas is dissol~ed into or at least minutely entr.ained
in the insulation layer material 16 as it is extruded as
a cover onto the rein~orced liner hose.
As constraining pressure is released as the insula-
tion layer 16 moves out of the crosshead die, some expansion
ta,kes place. Howe~er, the principal part of the expansion
takes place in curin~ chamber 52 where the entrained gas
~s heated and expands and blaws the insulation layer 16 into
a foam or sponqe condit~on. Furthermore, the temperature
in curin~ chamber 52 is sufficient to set the material vf
layer 16 b~ cross-linkt.ng or vulcanization so that it retains
,its foam~sponge characteristic even when the finished hose
IS cooled do~n~ In this way, a reinforced and insulated
flexible hose is produced, and the apparatus and method
by w~ich it is made is disclosed.
This invention ha~in~ been desc~ibed in its pre-
ferred embodiment, it is clear that It.iS susceptlble to
2,G numerous modifications and embodiments within the ability
of those skilled in the art and without the exercise of the
inventive faculty. Accordingl~, the scope of this invention '
I:s defined by the scope of the following claims.
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