POWER STEERING ATTENUATION HOSE CONSTRUCTION AND METHOD OF MAKING THE SAME

STRUCTURE DE DURITE D'ATTENUATION POUR DIRECTION ASSISTEE ET SON PROCEDE DE FABRICATION

English Abstract

A power steering attenuation hose construction and method of making the same
are provided, the hose construction (20, 20')
comprising an outer flexible hose unit (21, 21') having an inlet end (22, 56)
and an outlet end (23, 59), a restrictor unit (24, 24') disposed
in the outer hose unit (21, 21') and dividing the interior (25) of the outer
hose unit into an inlet chamber (26, 26') and an outlet chamber
(27, 27') interconnected by the restrictor unit (24, 24'), a first flexible
tuning cable unit (36, 36') being interconnected to the inlet end (22,
56) and being disposed in the inlet chamber (26, 26'), and a second flexible
tuning cable unit (45, 45') being interconnected to the restrictor
unit (24, 24') and being disposed in the outlet chamber (27, 27'), each of the
tuning cable units (36, 45; 36', 45') having an open outlet end
(41, 49'; 41', 49') spaced from the outlet end (42, 50; 65, 50') of its
respective chamber (26, 27; 26', 27'), the ratio of the effective length
(L1, L1') of the first tuning cable unit (36, 36') to the effective length
(L2, L2') of the second tuning cable (45, 45') being approximately
3 to 2 or higher.

French Abstract

On décrit une structure de durite d'atténuation pour direction assistée et son procédé de fabrication, la structure de la durite (20, 20') comprenant une enveloppe extérieure souple (21, 21') pourvue d'une entrée (22, 56) et d'une sortie (23, 59); une unité de réduction (24, 24') disposée dans l'enveloppe extérieure (21, 21') et divisant l'intérieur (25) de cette enveloppe en un compartiment d'entrée (26, 26') et un compartiment de sortie (27, 27') reliés entre eux par l'unité de réduction (24, 24'); un premier système de câble de réglage flexible (36, 36') relié à l'entrée, (22, 56) et disposé dans le compartiment d'entrée (26, 26'); et un second système de câble de réglage flexible (45, 45') relié à l'unité de réduction (24, 24') et disposé dans le compartiment de sortie (27, 27'), chacun des deux systèmes de réglage (36, 45; 36', 45') étant pourvu d'une extrémité de sortie ouverte (41, 49; 41', 49') espacée par rapport à la sortie (42, 50; 65, 50') de son compartiment respectif (26, 27; 26' 27'), et le rapport entre la longueur efficace (L1, L1') du premier système de câble de réglage (36, 36') et la longueur efficace (L2, L2') du second câble de réglage (45, 45') ayant une valeur environ égale à 3/2 ou plus.

Claims

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CLAIMS:
1. A power steering attenuation hose
construction comprising an outer flexible hose means
(21, 21') having an inlet end (22, 56) and an outlet
end (23, 53), restrictor means (24; 24') disposed in
said outer hose means (21, 21') and dividing an
interior (25) of said outer hose means into an inlet
chamber (26, 26') and an outlet chamber (27, 27')
interconnected together by said restrictor means
(24, 24'), each of said chambers (26, 27; 26', 27')
having an inlet end and an outlet end, a first
flexible tuning cable means (36, 36') being
interconnected to said inlet end (22, 56) and being
disposed in said inlet chamber (26, 26'), and a
second flexible tuning cable means (45, 45') being
interconnected to said restrictor means (24, 24')
and being disposed in said outlet chamber (27, 27'),
each of said tuning cable means (36, 45; 36', 45')
having an open outlet end (41, 49; 41', 49') spaced
from said outlet end (42, 50; 65, 50') of its
respective chamber (26, 27; 26', 27'), characterized
in that a ratio of an effective length (L2, L1')
of said first tuning cable means (36, 36') to an
effective length (L2, L2') of said second tuning
cable means (45, 45') is approximately 3 to 2.
2. A method of making a power steering
attenuation hose construction comprising an outer
flexible hose means (21, 21') having an inlet end
(22, 56) and an outlet end (23, 53), restrictor
means (24, 24') disposed in said outer hose means
(21, 21') and dividing an interior (25) of said
outer hose means into an inlet chamber (26, 26') and
an outlet chamber (27, 27') interconnected together
by said restrictor means (24, 24'), each of said

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chambers (26, 27; 26', 27') having an inlet end and
an outlet end, a first flexible tuning cable means
(36, 36') being interconnected to said inlet end
(22, 56) and being disposed in said inlet chamber
(26, 26'), and a second flexible tuning cable means
(45, 45') being interconnected to said restrictor
means (24, 24') and being disposed in said outlet
chamber (27, 27'), each of said tuning cable means
(36, 45; 36', 45') having an open outlet end (41,
49; 41', 49') spaced from said outlet end (42, 50;
65, 50') of its respective chamber (26, 27; 26',
27'), characterized by the step of forming said
tuning cable means so that a ratio of an
effective length (L1, L1') of said first tuning
cable means (36, 36') to an effective length (L2,
L2') of said second tuning cable means (45, 45') is
approximately 3 to 2.
3. A hose construction or method of
making same as set forth in claim 1 or 2,
characterized in that said restrictor means (24,
24') has an inlet portion (42) and an outlet portion
(48) interconnected together by a restricting
portion (28) that has a transverse cross-sectional
area that is smaller than the transverse cross-
sectional area of the interior of each of said
tuning cable means (36, 45; 36', 45').
4. A hose construction or method of
making same as set forth in claim 3, characterized
in that one of said inlet portion and said outlet
portion of said restrictor means (24') comprises a
relatively long tubular member (61).
5. A hose construction or method of
making same as set forth in claim 4, characterized
in that said outer flexible hose means (21')
comprises two separate flexible hoses (55A, 55B)

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being spaced from each other by said long tubular
member (61), one of said two flexible hoses (55A)
having said inlet chamber (26') therein and the
other of said two flexible hoses (55B) having said
outlet chamber (27') therein.
6. A hose construction or method of
making same as set forth in claim 1 or 2,
characterized in that said ratio is approximately 2
to 1 and in that said inlet chamber (26, 26') and
said first tuning cable means (36, 36') cooperate
together to form a one-quarter wave reflector that
is adapted to attenuate a 10th order harmonic,
or in that said outlet chamber (27, 27') and
said second tuning cable means (45, 45') cooperate
together to form a one-quarter wave reflector that
is adapted to attenuate a 20th order harmonic.
7. A hose construction or method of
making same as set forth in claim 1 or 2,
characterized in that said ratio is approximately 3
to 2 and in that said inlet chamber (26, 26') and
said first tuning cable means (36, 36') cooperate
together to form a one-quarter wave reflector that
is adapted to attenuate a 20th order harmonic,
or in that said outlet chamber (27, 27') and
said second tuning cable means (45, 45') cooperate
together to form a one-quarter wave reflector that
is adapted to attenuate a 30th order harmonic.
8. A hose construction or method of
making same as set forth in claim 1 or 2,
characterized in that said effective length (L1,
L1') of said first tuning cable (36, 36') is
approximately 15.24 cm (six inches) and said
effective length (L2, L2') of said second tuning
cable (45, 45') is approximately 10.16 cm (four
inches), or in that said effective length (L1, L1')

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of said first tuning cable (36, 36') is
approximately 25.4 cm (ten inches) and said
effective length (L2, L2') of said second tuning
cable (45, 45') is approximately 12.7 cm (five
inches), or in that said effective length (L1, L1')
of said first tuning cable (36, 36') is
approximately 27.94 cm (eleven inches) and said
effective length (L2, L2') of said second tuning
cable (45, 45') is approximately 13.97 cm (five and
one-half inches), or in that said effective length
(L1, L1') of said first tuning cable (36, 36') is
approximately 38.1 cm (fifteen inches) and said
effective length (L2, L2') of said second tuning
cable (45, 45') is approximately 22.86 cm (nine
inches).

Description

CA 02207401 1997-06-09
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POWER STEERING ATTENUATION HOSE CONSTRUCTION AND
METHOD OF MAKING THE SAME
Technical Field
This invention relates to a new power
steering attenuation hose construction and to a new
method of making such a power steering attenuation
hose construction.
Backctround Art
It is known to provide a power steering
attenuation hose construction comprising an outer
flexible hose means having an inlet end and an
outlet end, restrictor means disposed in the outer
hose means and dividing the interior of the outer
hose means into an inlet chamber and an outlet
chamber interconnected together by the restrictor
means, each of the chambers having an inlet end and
an outlet end, a first flexible tuning cable means
being interconnected to the inlet end and being
disposed in the inlet chamber, and a second flexible
tuning cable means being interconnected to the
restrictor means and being disposed in the outlet
chamber, each of the turning cable means having an
open outlet end spaced from the outlet end of its
respective chamber, the ratio of the effective
length of the first tuning cable means to the
effective length of the second tuning cable being
approximately 1 to 1.
Disclosure of the Invention
It is one of the features of this
invention to provide a new power steering
attenuation hose construction which has improved
attenuation of the noise and/or vibration shudder
produced by the power steering fluid of vehicles
that are being parked or unparked at idle or very
low speeds of movement thereof, such as by barely

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moving into and out of a parking space or the like
while the wheels of the vehicle are being turned by
the power steering mechanism.
In particular, it is known that when a
vehicle such as a transportation vehicle is having
the wheels thereof turned by the power steering
mechanism of the vehicle during a parking operation
of the vehicle, substantial noise and/or vibration
(shudder) is produced by the fluid passing through
the power steering mechanism from the fluid pump
thereof to the effective steering structure whereby
some means is provided to attenuate such noise
and/or shudder.
For example, see the U.S. Patent to Klees,
No. 3,323,305, wherein a single tuning cable means
is utilized in a hose construction in the power
steering system to attenuate the noise and/or
shudder created by the pumped power steering fluid,
whereby this U.S. patent is being incorporated into
this disclosure by this reference thereto.
As previously stated, it is known to
utilize two such tuning cable means in series in the
hose construction means.
However, it was found according to the
teachings of this invention that if the two tuning
cable means have a certain ratio in the effective
lengths thereof, improved attenuation of the noise
and/or shudder is produced.
In particular, the prior known power
steering hose construction that has two tuning
cables disposed therein in series has a ratio of
approximately 1 to 1 for the effective lengths of
the tuning cables thereof.
However, it was found according to the
teachings of this invention that the ratio of the

I I I I
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effective length of the first tuning cable means to
the effective length of the second tuning cable
means should be approximately 3 to 2 or higher,
wherein the second tuning cable means may be
disposed downstream or upstream from the first
tuning cable means.
For example, one embodiment of this
invention comprises a power steering attenuation
hose construction comprising an outer flexible hose
ZO means having an inlet end and an outlet end,
restrictor means disposed in the outer hose means
and dividing the interior of the outer hose means
into an inlet chamber and an outlet chamber
interconnected together by the restrictor means,
each of the chambers having an inlet end and an
outlet end, a first flexible tuning cable means
being interconnected to the inlet end and being
disposed in the inlet chamber, and a second flexible
tuning cable means being interconnected to the
restricto= means and being disposed in the outlet
chamber, each of the tuning cable means having an
open outlet end spaced from the outlet end of its
respective chamber, a ratio of an effective
length of the first tuning cable means to an
effective length of the second tuning cable means
being approximately 3 to 2.
Accordingly, it is an object of this
invention to provide a new power steering
attenuation hose construction having one or more of
the novel features of this invention as set forth
above or hereinafter shown or described.
Another object of this invention is to
provide a new method of making such a power steering
attenuation hose construction, the method of this
invention having one or more of the novel features

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of this invention as set forth above or hereinafter
shown or described.
Brief Description of the Drawings
The features of the invention, and its
technical advantages, can be seen from the following
description of the preferred embodiments together
with the claims and the accompanying drawings, in
which:
FIG. 1. is a fragmentary perspective view
of a new power steering attenuation hose
construction of this invention;
FIG. 2A is an enlarged fragmentary cross-
sectional view taken substantially on the lines 2A-
2A of FIG. 1;
FIG. 2B is an enlarged fragmentary cross-
sectional view taken on lines 2B-2B of FIG. 1;
FIG. 3 is a perspective view of another
new power steering attenuation hose construction of
this invention;
FIG. 4 is an enlarged fragmentary cross-
sectional view taken on line 4-4 of FIG. 3, FIG. 4
being shown in straight form rather than the bent
form illustrated in FIG. 3; and
FIG. 5 is an enlarged fragmentary cross
sectional view taken on line 5-5 of FIG. 3 and is
also shown in straight form in FIG. 5 rather than in
bent form as illustrated in FIG. 3.
Descrit~tion of the Preferred Embodiments
While the various .features of this
invention are hereinafter illustrated and described
as providing power steering attenuation hose
construction of various configurations, it is to be
understood that the various features of this
invention can be used singly or in any combination
thereof to provide a power steering attenuation hose

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construction having any other configuration as
desired.
Therefore, this invention is not to be
limited to only the embodiments illustrated in the
drawings, because the drawings are merely utilized
to illustrate one of the wide variety of uses of
this invention.
Referring now to FIGS. 1, 2A and 2B, a new
power steering attenuation hose construction of this
invention is generally indicated by the reference
numeral 20 and comprises an outer flexible hose
means 21 formed of any suitable polymeric material
~
steering hose art and
as is well known in the power
has an inlet end 22 and an outlet end 23 with a
metallic tubular restrictor means 24 being disposed
in the outer hose means 21 and dividing the interior
25 of the outer hose means 21 into an inlet chamber
26 and an outlet chamber 27 that are interconnected
together by a restricting passage 28 formed through
the restrictor means 24.
A metallic inlet tube or conduit 29 has an
end 30 thereof disposed in the inlet end 22 of the
outer hose means 21 and is held therein by an outer
cylindrical body portion or fitting 32 also formed
of metallic material and having been inwardly
crimped as illustrated in FIG. 2A to hold the inlet
end 22 of the outer hose means 21 on the end 30 of
the conduit 29 all in a manner well known in the
art. For example, see the .aforementioned U.S.
patent to Klees, No. 3,323,305.
Similarly, a metallic outlet tube or
conduit 33 has an end 34 thereof disposed in the
outlet end 23 of the outer hose means 21 and is held
thereon by an outer metallic cylindrical member or
fitting 35 having been crimped to the end 23 in the

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manner illustrated in FIG. 2B, the inlet conduit 29
and the outlet conduit 33~forming part of a complete
power steering arrangement (not shown) for passing
the power steering fluid from a pump means of the
power steering arrangement through the power
steering attenuation hose construction 21 to the
steering mechanism of a vehicle or the like all in
the manner fully disclosed in the aforementioned
patent to Klees, No. 3,323,305, whereby it is
believed only necessary to describe the structure of
the new power steering attenuation hose construction
of this invention as the use thereof in a power
steering mechanism need not be further described.
Accordingly, it can be seen in FIGS. 1 and
15 2A that a first flexible tuning cable means 36 that
is formed of metallic material has one end 37
thereof crimped in an opening 3 8 of the end 3 0 of
the inlet tube 29 so as to be fastened thereto and
be in fluid communication therewith, while another
20 end 39' of the tuning cable means 36 has a
cylindrical tubular end member 40 fastened thereon
and providing an open outlet end 41 for the tuning
cable means 36 which is spaced from an adjacent end
42 of the restrictor means 24 a distance that is
indicated by the reference character S1 in FIG. 2A
while the effective length of the first tuning cable
means 36 in the inlet chamber 26 of the hose means
21 is represented by the reference character L1 in
FIG. 2A.
Thus, it can be seen that the inlet
chamber 26 of the hose construction 21 as
illustrated in FIG. 2A has an annular chamber 43
surrounding the cable means 36 from the inlet end 37
thereof all the way to the open outlet end 41
thereof and then has a larger chamber 44 formed in

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the space between the outlet end 41 of the cable
means 36 and the adjacent end 42 of the restrictor
means 24.
As fully described in the aforementioned
U.S. patent to Klees, No. 3,323,305, the length Sl
of the space 44 at the outlet end 41 of the first
tuning cable means 36 is approximately 2.54 cm (one
inch) and the effective length L1 of the cable means
36, in combination with the flexibility of the outer
hose 21 and the annular space 43, is so selected
that the inlet chamber 26 becomes a quarter wave
reflector means that attenuate a certain primary
order harmonic of the noise being created by the
power steering fluid being pumped through the power
steering hose construction 21. The inlet chamber
means 26 also has been found to provide a three-
quarter wave reflector means for a subsequent higher
order harmonic of the noise as will be hereinafter
described.
A second metallic flexible tuning cable
mans 45 similar to the first cable means 36 is
disposed in the outlet chamber means 27 of the outer
hose means 21 and has an inlet end 46 thereof
disposed in an opening 47 in an end 48 of the
restrictor means 24 and is held therein by the end
48 having been crimped thereto in a manner well
known in the art whereby an open outlet end 49 of
the cable means 45 is spaced from an adjacent end 50
of the outlet tube 33 a distance designated S2 in
FIG. 2B which is also approximately 2.54 cm (one
inch) .
Thus, it can be seen that the second cable
means 45 defines an annular chamber 51 in the outlet
chamber 27 about the cable means 45 from its inlet
end 46 to its open outlet end 49 which is defined by

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a metallic cylindrical open ended cap means 52
secured on an outlet end 53 of the cable means 45 in
the same manner as the outlet cap 40 of FIG. 2A.
The outlet end 49 of the cable means 45
cooperates with the end surface 50 of the outlet
conduit 33 to define a larger chamber 54 in the
outlet chamber 27 whereby the effective length of
the tuning cable means 45 is designated by the
distance L2 in FIG. 2B.
It has been found that the second tuning
cable means 45 also provides a quarter wave
reflector means that attenuate a higher order
harmonic of the noise than the primary order
harmonic that is attenuated by the first cable means
36 and also acts as a three-quarter wave reflector
means for attenuating a subsequent higher order
harmonic.
It has been found according to the
teachings of this invention that by making the
lengths L1 and L2 of the respective tuning cables 36
and 45 of a ratio of 2 to 1 together with making the
restrictor passage 28 of the restrictor means 24
with a transverse cross-sectional area that is less
than the transverse cross-sectional area of the
openings passing through the tuning cable means 36
and 45 , the first tuning cable means 3 6 can be tuned
to attenuate a 10th order harmonic of the noise with
the quarter wave reflector means thereof and the
second tuning cable means 45 can be tuned to
attenuate the 20th order harmonic of the noise with
the quarter wave reflector means thereof while the
first tuning cable means 36 with the three-quarter
wave reflector means thereof will additionally
attenuate the 30th order harmonic of the noise and
the second tuning cable means 45 with the three-

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quarter wave reflector means thereof will
additionally attenuate the 60th order harmonic.
Additional higher order harmonics of the noise may
a
also be attenuated in a like manner by such a hose
construction 21 of this invention:
For example, it is to be understood that
the first cable means 36 will also alternate the
50th order harmonic of the noise with the five-
quarter wave reflector means thereof and the 70th
order harmonic of the noise with the seven-quarter
wave reflector means thereof, etc. The second
tuning cable means 45 will also attenuate the 100th
order harmonic of the noise with the five-quarter
wave reflector means thereof and the 140th order
harmonic of the noise with the seven-quarter wave
reflector means thereof, etc.
It was found in one working embodiment of
this invention that the length L1 can be
approximately 15.24 cm (six inches) and the length
L2 can be approximately 10.16 cm (four inches). In
another working embodiment of this invention the
length L1 is approximately 38.1 cm (fifteen inches)
and the length L2 is approximately 22.86 cm (nine
inches). In both working embodiments, the internal
diameter of the restrictor passage means 28 is
approximately 4.24 mm and the internal diameter of
the tuning cable means 36 and 45 is approximately
5.75 mm while the outside diameter of the tuning
cable means 36 and 45 is approximately 7.55 mm.
a 30 In addition, it has been found that when
the ratio of the length L1 to the length L2 is
a approximately 3 to 2, the first tuning cable means
with the quarter wave reflector means thereof
attenuate the 20th order harmonic of the noise and
the second tuning cable means with the quarter wave

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reflector means thereof attenuate the 30th order
harmonic of the noise. The first tuning cable means
in such 3 to 2 ratio also attenuate the 60th order
harmonic of the noise with the three-quarter wave ,,
reflector means thereof and the second cable means
also attenuate the 90th order harmonic of the noise
with the three-quarter wave reflector means thereof .
A working embodiment of this invention
with the 2 to 1 ratio has a length L1 of
approximately 27.94 cm (eleven inches) and a length
L2 of approximately 13.97 cm (five and one-half
inches). Another working embodiment of this
invention with the 2 to 1 ratio has the length L1 of
approximately 25.4 cm (ten inches) and the length L2
of approximately 12.7 cm (five inches).
In particular, the embodiment where L1 is
25.4 cm (ten inches) and L2 is 12.7 cm (five inches)
is illustrated in FIGS. 3-5 and comprises a power
steering attenuation hose construction of this
invention that is generally indicated by the
reference numeral 20' and the parts thereof that are
similar to the parts of the power steering
attenuation hose construction 20 of FIGS. 1, 2A and
2B are indicated by like reference numerals followed
by a prime mark.
As illustrated in FIGS. 3-5, the power
steering attenuation hose construction 20' of this
invention comprises an outer flexible hose means 21'
that is formed from two separate flexible outer
hoses 55A and 55B respectively having inlet ends 56
and 57 and outlet ends 58 and 59, the outlet end 58
of the first flexible hose 55A being fluidly
interconnected to an inlet end 60 of.a metallic tube
or conduit 61 that has an outlet end 62 thereof
interconnected to the restrictor means 24' that is

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disposed in the inlet end 57 of the second hose 55B
and fastened thereto by a fitting 63 in the same
manner as the fittings 32 and 35 previously
described.
However, the end 62 of -the conduit 61 in
the working embodiment of this invention is directly
interconnected to the second hose 55B by a fitting
similar to the fitting 32 without having the
restrictor means 24'. In fact it is believed that
if a restrictor means 24' is used, the same could be
at the outlet end of the first hose 55A, if desired.
Thus, the tube 61 itself may function similar to a
restriction means by dividing the hose construction
20' into the separate chambers 26' and 27'.
Similarly, the fitting 32' fastens the
inlet conduit means 29' to the inlet end 56 of the
first hose 55A while a similar fitting 64 fastens
the inlet end 60 of the tube 61 to the outlet end 58
of the first hose 55A. Also, the fitting 35'
fastens the outlet end 59 of the second hose 55B to
the outlet conduit means or pipe 33'.
In order to have the power steering
attenuation hose construction 20' be positioned in
assembled relation with a vehicle structure having
a
particular configuration, the hose construction 20'
is bent into the particular shape illustrated in
FIG. 3 wherein the first hose means 55A and second
hose means 55B, as well as the interconnecting
conduit 61, have been configurations (even though
shown in straight form in FIGS. 4 and 5 to
facilitate the viewing thereof). Thus, it can be
seen that the hose constructions 20 and 20' of this
invention can be bent into various configurations
thereof and will still function in the manner
previously described.

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In any event, it can be seen in FIGS. 4
and 5 that the first hose 55A has a first tuning
cable means 36' disposed therein and having an
effective length L1' while the open end means 41' ,
thereof is spaced from an end surface 65 of the
inlet end 60 of the conduit 61 a distance S1' which
is approximately 2.54 cm (one inch).
Similarly, the second hose 55B has a
second tuning cable means 45' disposed therein and
having an effective length L2' so that the free end
49' of the second tuning cable means 45' is spaced
from the end 50' of the outlet conduit means 33' by
a distance S2' which is also approximately 2.54 cm
(one inch).
The lengths L1' and L2' provide a ratio of
approximately 2 to 1 as the length L1' in the
embodiment of FIGS. 3-5 is approximately 25.4 cm
(ten inches) and the length L2' thereof is
approximately 12.7 cm (five inches).
Therefore, it can be seen that each power
steering attenuation hose construction of this
invention has two open ended tuning cables in series
with a restrictor means disposed therebetween that
has a restricting passage with a cross-sectional
area that is less than the cross-sectional areas
through the two tuning cable means so that the two
chambers receiving the respective tuning cable means
are effectively divided from each other by the
restrictor means in such a manner that the first
chamber means will attenuate a primary order
r
harmonic of the noise with the quarter wave
reflector means thereof and the second chamber means
will attenuate a certain higher order harmonic of
the noise with the quarter wave reflector means
thereof.

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It can also be seen that the power
steering fluid in the hose construction 20
previously described will be forced through the
inlet conduit 29 and cable means 36 to exit out of
the open end 41 thereof into the ~ f first chamber
25
and then pass through the passage 28 of the
restrictor means 24 into the second tuning cable
means 45 to exit out of the open end 49 thereof to
fill the second chamber means 25 and then exit out
through the outlet pipe or conduit 33 while having
the noise thereof attenuated in the manner
previously described.
Similarly, it can be seen in FIGS. 3-5
that the power steering fluid passes from the inlet
pipe 29' through the first tuning cable means 3d' to
fill the first chamber 43' and then exits through
the conduit 61 of the restrictor means 24' to pass
through the restrictor means 24' into the second
tuning cable means 45' to exit out of the open end
49' thereof and fill the second chamber means 27'
before exiting out of the outlet conduit 33' while
having the noise thereof attenuated in the manner
previously described.
Therefore, it can be seen that this
invention not only provides a new power steering
attenuation hose construction, but also this
invention provides a new method of making such a
power steering attenuation hose construction.
While the forms and methods of this
invention now preferred have been illustrated and
described as required, it is to be understood that
other forms and method steps can be utilized and
still fall within the scope of the appended claims.

Representative Drawing