Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENTION
(l) Field of the Invention
The subject invention relates to a motion trans-
mitting remote control assembly of the type used in trans-
mitting tension and compression or rotation in a curvedpath by a flexible motion transmitting core element. The
assembly generally includes a flexible conduit, a core
element supported for axial movement within the cor,duit,
anti-friction members for facilitating movement of the
core element within the conduit and end fittings at both
ends of the conduit for attaching the assembly to a
support structure.
t2) Description of the Prior Art
A motion transmitting remote control assembly
should be strong enough to be used in adverse environments,
inexpensive to manufacture and have means provided therein
for minimizing the friction that is generated by the
movement of the core element therewithin. Various at-
tempts have been made to solve the problem of friction
by providing a surface having high lubricity between the
core element and outer casing of the conduit. For example,
many conduits include a flexible plastic inner tubular
member having low frictional resistance such that the core
element is movably supported within the tubular member.
2S Even though cables of this class are, to a degree, self-
lubricating, it is frequently necessary to supplement
these cables with added lubricant. However, the lubricant
is usually wiped out of the bearing areas of the core ele-
ment and sheath by movement of the core element and, hence,
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areas of high -friction develop.
Further development has been made in using al-
ternative plastics and o~her ma~erials of high lubrici~y
to coat the inner core member. The preferred organic poly-
5 meric materials have been teflon~ nylon and polyalkylenes,such as polyethylene, polypropylene and their copolymers.
Even though these organic polymeric materials have con-
siderable inherent lubricity, it is still sometimes nec-
essary to provide additional lubricant. Therefore, the
problems previously mentioned still exist.
Another problem which exists with the use of
cables having plastic sheath inner core members is the
added thickness to the diameter of the cable which is con-
tributed by the plastic sheath.
SUMMARY OF THE INVENTION
The instant invention provides a motion trans-
mitting remote control assembly of the type for trans-
mitting forces along a curved path by a motion transmitting
core element. The assembly comprises a motion transmitting
core element movably supported by a guide means. The guide
means includes a tubular member defined by braided car-
bonous filaments having the property of being frictionally
broken off into microparticles, the microparticles having
inherent lubricity. The tubular member engages the core
element such that movement of the core element friction-
ally breaks off the microparticles for facilitating move-
ment of the core element within the guide means.
PRIOR ART STATEMENT
The U.S. Patents 3,192,795 to Pierce, issued
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July 6, ls65~ and 3,359,822 to Hurlow, issued December 26,
1967, are examples of push/pull cables with plastic-lined
sheaths. The Pierce patent teaches a core element movably
(rotatably and longitudinally) supported within an inner
tubular member. The tubular member is made from materials
such as nylon or teflon~ The Hurlow patent teaches a
push/pull cable consisting of a core element received in a
sheath, the core or sheath being coated with a plastic
material designed to reduce friction. The multiplicity of
reservoirs formed by the spaces between the coils of
plastic lining assists in lubrication of the core element.
As with other push/pull cable assemblies having plastic-
lined sheaths, the Pierce and Hurlow inventions require
added lubrication. This lubrication is not uniformly
applied to the cable. Furthermore, the additional plastic
liners add measurably to the smallest necessary diameter of
a functional cable.
BRIEF DESCRIPTION OF THE DRAWINGS
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:
FIGURE 1 is an elevational view of a preferred
embodiment of the instant invention;
FIGURES 2 and 3 are enlarged views partially
broken away and in cross section of alternative preferred
embodiments constructed in accordance with the instant
invention;
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* Tr~le~olrk
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FIGIJRE 4 is a cross-sectional view taken sub-
stantially along line 4-4 o-f FIG'JRE 2;
FIGIJRE 5 is a cross-sectional view taken sub-
stantially along line 5-5 of FIGURE 3; and
FIGURE 6 is an enlarged fragmentary view o-f the
tubular member defined by braided carbonous filaments.
DESCRIPTI ON OF PREFERRED EMBODIMENT
A flexible motion-transmitting remote control
assembly of the type for transmitting forces along a
curved path by a motion transmitting core element con-
structed in accordance with the instant invention is
generally shown at 10 in FIGURF. 1.
The motion transmitting remote control assembly
10 includes a guide means generally indicated at 12 and
a flexible motion-transmitting core element 14. The core
element 14 may take various forms, but in the preferred
embodiment it is shown as a metal wire element having loops
15 at each end thereof for attachment to control members
for transmitting motion therebetween.
The guide means 12 includes a tubular member 16
defined by braided carbonous filaments having the property
of being frictionally broken off into microparticles that
have inherent lubricity. The braided carbonous filamen~s
o~ the tubular member 16 comprise a plurality of strands
17 which are woven together to define a diagonal pattern
as illustrated in FIGURE 6. Each strand 17 comprises a
plurality of hair-like fibers. The individual strands 17
cross one another at a helical angle relative to the
longitudinal axis of the assembly. The tubular member 16
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engages the core element 14 such that movement of the core
element 14 frictionally breaks off microparticles of the
braided carbonous filaments for facilitating movement of
the core element ~ithin the guide means. The broken-off
microparticles either adhere to the core element, remain
freely suspended between the strands 17 and the core ele-
ment, or lodge among the fibers making up the strands 17.
The movement of the core element also results in conferring
a charge on the microparticles relative to the core ele-
ment which also attracts microparticles to the coreelement, Therefore, the core element is coated with micro-
particles resulting in a lubrica~ing coating thereabout.
In the preferred embodiment, the hair-like
fibers are composed of graphite. Other carbonous com-
pounds having the above-described properties can be used
in accordance with the instant invention.
Fibers and strands thereof which may be utilized
are marketed under the trademark "PANEX" by Stackpole
Fibers Co., Inc. of Lowell, Massachusetts.
Referring to FIGURF, 2, a flexible solid tube 18
surrounds the woven carbonous filaments defining the tubu-
lar member 16. The flexible tube 18 is made of a suitable
plastic or organic polymeric material. Surrounding the
flexible tube 18 is a load-bearing means for carrying
tension forces as the core element 14 is moved axially
and in some instances providing hoop strength. The load-
bearing means includes a plurality of long lay wires 20
wrapped helically about the flexible tube 18. A casing
22 is disposed about the long lay wires 20. The casing
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22 can be made of a suitable plastic or organic polymeric
material and extruded about the long lay wires 20.
Referring to FIGURE 1, the guide means 12 in-
cludes at least one end Eitting 24 of organic polymeric
material secured to the outer casing 22 and is adapted
for attachment to a support structure. The fittings 24
are pre-ferably made of an organic polymeric or plastic
material and are molded about the casing 22. In one
possible embodiment the casing 22 may have grooves or
other deformities therein so that a mechanical inter-
locking engagement is made when the fitting 24 is molded
thereabout.
The guide means 12 as shown in FIGURES 2 and 3
is flexible so that the assembly is adapted to negotiate
bends in the environment in which it is used.
FIGURE 3 shows another possible embodiment of
the instant invention. The core element 14 is again sup-
ported within a guide means generally indicated at 12.
The guide means includes the tubular member 16 defined by
braided carbonous filaments for engaging the core element
14 and for facilitating movement thereof. A load-bearing
means consists of a plurality of long lay wires 20
wrapped helically abou~ and in engagement with the tubu-
lar member 16. A casing 22 preferably made of an organic
polymeric material, is disposed about the long lay wires
26. In the embodiment of FIGURE 3 the long lay wires 26
directly engage the tubular member 16.
In both embodiments there is a significant de-
crease in the diameter of the assembly as compared to
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prior art assemblies. This is particularly true of the
embodiment of FIGIJR~ 3 by not including the inner flexible
tube 18. Therefore, the instant invention can assume an
embodiment which includes a means for minimizing the
friction of the rotational and longitudinal movement of
the core element and adds very little to the bulk of the
assembly. Also, the braided carbonous filaments provide
a continuous lubricating surface to the core element
throughtout the flexible conduit assembly.
The invention has been described in an illus-
trative manner, and it is to be understood that the
terminology which has been used is intended to be in the
nature of words of description rather than of limitation.
Obviously, many modifications and variations of
the present invention are possible in light of the above
teachings. It is, therefore, to be understood that within
the scope of the appended claims, the invention may be
practiced otherwise than as specifically described.
